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* [PATCH] Input: add driver for Cypress APA I2C Trackpad
@ 2012-07-10 22:29 Benson Leung
  2012-07-16 11:05 ` Henrik Rydberg
  2012-12-06  0:48 ` [PATCH v2 0/1] " Benson Leung
  0 siblings, 2 replies; 14+ messages in thread
From: Benson Leung @ 2012-07-10 22:29 UTC (permalink / raw)
  To: dmitry.torokhov, rydberg, dudl, djkurtz, olofj, linux-input,
	linux-kernel
  Cc: Benson Leung

This patch introduces a driver for Cypress All Points Addressable
I2C Trackpad, including the one in the Samsung Series 5 550 Chromebook.

This device is compatible with MT protocol type B, providing identifiable
contacts.

This driver also implements firmware updating capability via
request_firmware.

Signed-off-by: Dudley Du <dudl@cypress.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
---
 drivers/input/mouse/Kconfig  |   13 +
 drivers/input/mouse/Makefile |    1 +
 drivers/input/mouse/cyapa.c  | 1493 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1507 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/mouse/cyapa.c

diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
index cd6268c..2767c3c 100644
--- a/drivers/input/mouse/Kconfig
+++ b/drivers/input/mouse/Kconfig
@@ -193,6 +193,19 @@ config MOUSE_BCM5974
 	  To compile this driver as a module, choose M here: the
 	  module will be called bcm5974.
 
+config MOUSE_CYAPA
+	tristate "Cypress APA I2C Trackpad support"
+	depends on I2C
+	help
+	  This driver add support for Cypress All Points Addressable (APA)
+	  I2C Trackpads, including the one in the Samsung Series 5 550
+	  Chromebook.
+
+	  Say Y here if you have a Cypress APA I2C Trackpad.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called cyapa.
+
 config MOUSE_INPORT
 	tristate "InPort/MS/ATIXL busmouse"
 	depends on ISA
diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
index 46ba755..10b4773 100644
--- a/drivers/input/mouse/Makefile
+++ b/drivers/input/mouse/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
 obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
 obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
 obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
+obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
 obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
 obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
 obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
new file mode 100644
index 0000000..8af0970
--- /dev/null
+++ b/drivers/input/mouse/cyapa.c
@@ -0,0 +1,1493 @@
+/*
+ * Cypress APA trackpad with I2C interface
+ *
+ * Author: Dudley Du <dudl@cypress.com>
+ * Further cleanup and restructuring by:
+ *   Daniel Kurtz <djkurtz@chromium.org>
+ *   Benson Leung <bleung@chromium.org>
+ *
+ * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Google, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/semaphore.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+/* APA trackpad firmware generation */
+enum cyapa_gen {
+	CYAPA_GEN1 = 0x01,  /* only one finger supported. */
+	CYAPA_GEN2 = 0x02,  /* max five fingers supported. */
+	CYAPA_GEN3 = 0x03,  /* support MT-protocol B with tracking ID. */
+};
+
+#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
+
+/* commands for read/write registers of Cypress trackpad */
+#define CYAPA_CMD_SOFT_RESET       0x00
+#define CYAPA_CMD_POWER_MODE       0x01
+#define CYAPA_CMD_DEV_STATUS       0x02
+#define CYAPA_CMD_GROUP_DATA       0x03
+#define CYAPA_CMD_GROUP_CTRL       0x04
+#define CYAPA_CMD_GROUP_CMD        0x05
+#define CYAPA_CMD_GROUP_QUERY      0x06
+#define CYAPA_CMD_BL_STATUS        0x07
+#define CYAPA_CMD_BL_HEAD          0x08
+#define CYAPA_CMD_BL_CMD           0x09
+#define CYAPA_CMD_BL_DATA          0x0a
+#define CYAPA_CMD_BL_ALL           0x0b
+#define CYAPA_CMD_BLK_PRODUCT_ID   0x0c
+#define CYAPA_CMD_BLK_HEAD         0x0d
+
+/* report data start reg offset address. */
+#define DATA_REG_START_OFFSET  0x0000
+
+#define BL_HEAD_OFFSET 0x00
+#define BL_DATA_OFFSET 0x10
+
+/*
+ * Operational Device Status Register
+ *
+ * bit 7: Valid interrupt source
+ * bit 6 - 4: Reserved
+ * bit 3 - 2: Power status
+ * bit 1 - 0: Device status
+ */
+#define REG_OP_STATUS     0x00
+#define OP_STATUS_SRC     0x80
+#define OP_STATUS_POWER   0x0c
+#define OP_STATUS_DEV     0x03
+#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
+
+/*
+ * Operational Finger Count/Button Flags Register
+ *
+ * bit 7 - 4: Number of touched finger
+ * bit 3: Valid data
+ * bit 2: Middle Physical Button
+ * bit 1: Right Physical Button
+ * bit 0: Left physical Button
+ */
+#define REG_OP_DATA1       0x01
+#define OP_DATA_VALID      0x08
+#define OP_DATA_MIDDLE_BTN 0x04
+#define OP_DATA_RIGHT_BTN  0x02
+#define OP_DATA_LEFT_BTN   0x01
+#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
+			  OP_DATA_LEFT_BTN)
+
+/*
+ * Bootloader Status Register
+ *
+ * bit 7: Busy
+ * bit 6 - 5: Reserved
+ * bit 4: Bootloader running
+ * bit 3 - 1: Reserved
+ * bit 0: Checksum valid
+ */
+#define REG_BL_STATUS        0x01
+#define BL_STATUS_BUSY       0x80
+#define BL_STATUS_RUNNING    0x10
+#define BL_STATUS_DATA_VALID 0x08
+#define BL_STATUS_CSUM_VALID 0x01
+
+/*
+ * Bootloader Error Register
+ *
+ * bit 7: Invalid
+ * bit 6: Invalid security key
+ * bit 5: Bootloading
+ * bit 4: Command checksum
+ * bit 3: Flash protection error
+ * bit 2: Flash checksum error
+ * bit 1 - 0: Reserved
+ */
+#define REG_BL_ERROR         0x02
+#define BL_ERROR_INVALID     0x80
+#define BL_ERROR_INVALID_KEY 0x40
+#define BL_ERROR_BOOTLOADING 0x20
+#define BL_ERROR_CMD_CSUM    0x10
+#define BL_ERROR_FLASH_PROT  0x08
+#define BL_ERROR_FLASH_CSUM  0x04
+
+#define REG_BL_KEY1 0x0d
+#define REG_BL_KEY2 0x0e
+#define REG_BL_KEY3 0x0f
+#define BL_KEY1 0xc0
+#define BL_KEY2 0xc1
+#define BL_KEY3 0xc2
+
+#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
+#define BLK_HEAD_BYTES 32
+
+/* Macro for register map group offset. */
+#define CYAPA_REG_MAP_SIZE  256
+
+#define PRODUCT_ID_SIZE  16
+#define QUERY_DATA_SIZE  27
+#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
+
+#define REG_OFFSET_DATA_BASE     0x0000
+#define REG_OFFSET_CONTROL_BASE  0x0000
+#define REG_OFFSET_COMMAND_BASE  0x0028
+#define REG_OFFSET_QUERY_BASE    0x002a
+
+#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
+
+#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
+#define SET_POWER_MODE_DELAY   10000  /* unit: us */
+#define SET_POWER_MODE_TRIES   5
+
+#define PWR_MODE_MASK   0xfc
+#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
+#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
+#define PWR_MODE_BTN_ONLY    (0x01 << 2)
+#define PWR_MODE_OFF         (0x00 << 2)
+
+#define BTN_ONLY_MODE_NAME   "buttononly"
+
+#define PWR_STATUS_MASK      0x0c
+#define PWR_STATUS_ACTIVE    (0x03 << 2)
+#define PWR_STATUS_IDLE      (0x02 << 2)
+#define PWR_STATUS_BTN_ONLY  (0x01 << 2)
+#define PWR_STATUS_OFF       (0x00 << 2)
+
+/*
+ * CYAPA trackpad device states.
+ * Used in register 0x00, bit1-0, DeviceStatus field.
+ * After trackpad boots, and can report data, it sets this value.
+ * Other values indicate device is in an abnormal state and must be reset.
+ */
+#define CYAPA_DEV_NORMAL  0x03
+
+enum cyapa_state {
+	CYAPA_STATE_OP,
+	CYAPA_STATE_BL_IDLE,
+	CYAPA_STATE_BL_ACTIVE,
+	CYAPA_STATE_BL_BUSY,
+	CYAPA_STATE_NO_DEVICE,
+};
+
+
+struct cyapa_touch {
+	/*
+	 * high bits or x/y position value
+	 * bit 7 - 4: high 4 bits of x position value
+	 * bit 3 - 0: high 4 bits of y position value
+	 */
+	u8 xy;
+	u8 x;  /* low 8 bits of x position value. */
+	u8 y;  /* low 8 bits of y position value. */
+	u8 pressure;
+	/* id range is 1 - 15.  It is incremented with every new touch. */
+	u8 id;
+} __packed;
+
+/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
+#define CYAPA_MAX_MT_SLOTS  15
+
+/* CYAPA reports up to 5 touches per packet. */
+#define CYAPA_MAX_TOUCHES  5
+
+struct cyapa_reg_data {
+	/*
+	 * bit 0 - 1: device status
+	 * bit 3 - 2: power mode
+	 * bit 6 - 4: reserved
+	 * bit 7: interrupt valid bit
+	 */
+	u8 device_status;
+	/*
+	 * bit 7 - 4: number of fingers currently touching pad
+	 * bit 3: valid data check bit
+	 * bit 2: middle mechanism button state if exists
+	 * bit 1: right mechanism button state if exists
+	 * bit 0: left mechanism button state if exists
+	 */
+	u8 finger_btn;
+	struct cyapa_touch touches[CYAPA_MAX_TOUCHES];
+} __packed;
+
+/* The main device structure */
+struct cyapa {
+	enum cyapa_state state;
+
+	struct i2c_client	*client;
+	struct input_dev	*input;
+	char *phys;	/* device physical location */
+	int irq;
+	bool irq_wake;  /* irq wake is enabled */
+
+	/* power mode settings */
+	u8 suspend_power_mode;
+
+	/* read from query data region. */
+	char product_id[16];
+	u8 capability[14];
+	u8 fw_maj_ver;  /* firmware major version. */
+	u8 fw_min_ver;  /* firmware minor version. */
+	u8 hw_maj_ver;  /* hardware major version. */
+	u8 hw_min_ver;  /* hardware minor version. */
+	enum cyapa_gen gen;
+	int max_abs_x;
+	int max_abs_y;
+	int physical_size_x;
+	int physical_size_y;
+};
+
+static const u8 bl_activate[] = { 0x00, 0xff, 0x38, 0x00, 0x01, 0x02, 0x03,
+		0x04, 0x05, 0x06, 0x07 };
+static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
+		0x04, 0x05, 0x06, 0x07 };
+static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
+		0x05, 0x06, 0x07 };
+
+struct cyapa_cmd_len {
+	unsigned char cmd;
+	unsigned char len;
+};
+
+#define CYAPA_ADAPTER_FUNC_NONE   0
+#define CYAPA_ADAPTER_FUNC_I2C    1
+#define CYAPA_ADAPTER_FUNC_SMBUS  2
+#define CYAPA_ADAPTER_FUNC_BOTH   3
+
+static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
+	{CYAPA_OFFSET_SOFT_RESET, 1},
+	{REG_OFFSET_COMMAND_BASE + 1, 1},
+	{REG_OFFSET_DATA_BASE, 1},
+	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
+	{REG_OFFSET_CONTROL_BASE, 0},
+	{REG_OFFSET_COMMAND_BASE, 0},
+	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
+	{BL_HEAD_OFFSET, 3},
+	{BL_HEAD_OFFSET, 16},
+	{BL_HEAD_OFFSET, 16},
+	{BL_DATA_OFFSET, 16},
+	{BL_HEAD_OFFSET, 32},
+	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
+	{REG_OFFSET_DATA_BASE, 32}
+};
+
+#define CYAPA_FW_NAME		"cyapa.bin"
+#define CYAPA_FW_BLOCK_SIZE	64
+#define CYAPA_FW_HDR_START	0x0780
+#define CYAPA_FW_HDR_BLOCK_COUNT  2
+#define CYAPA_FW_HDR_BLOCK_START  (CYAPA_FW_HDR_START / CYAPA_FW_BLOCK_SIZE)
+#define CYAPA_FW_HDR_SIZE	(CYAPA_FW_HDR_BLOCK_COUNT * \
+				 CYAPA_FW_BLOCK_SIZE)
+#define CYAPA_FW_DATA_START	0x0800
+#define CYAPA_FW_DATA_BLOCK_COUNT  480
+#define CYAPA_FW_DATA_BLOCK_START  (CYAPA_FW_DATA_START / CYAPA_FW_BLOCK_SIZE)
+#define CYAPA_FW_DATA_SIZE	(CYAPA_FW_DATA_BLOCK_COUNT * \
+				 CYAPA_FW_BLOCK_SIZE)
+#define CYAPA_FW_SIZE		(CYAPA_FW_HDR_SIZE + CYAPA_FW_DATA_SIZE)
+#define CYAPA_CMD_LEN		16
+
+static void cyapa_detect(struct cyapa *cyapa);
+
+#define BYTE_PER_LINE  8
+void cyapa_dump_data(struct cyapa *cyapa, size_t length, const u8 *data)
+{
+	struct device *dev = &cyapa->client->dev;
+	int i;
+	char buf[BYTE_PER_LINE * 3 + 1];
+	char *s = buf;
+
+	for (i = 0; i < length; i++) {
+		s += sprintf(s, " %02x", data[i]);
+		if ((i + 1) == length || ((i + 1) % BYTE_PER_LINE) == 0) {
+			dev_dbg(dev, "%s\n", buf);
+			s = buf;
+		}
+	}
+}
+#undef BYTE_PER_LINE
+
+/*
+ * cyapa_i2c_reg_read_block - read a block of data from device i2c registers
+ * @cyapa  - private data structure of driver
+ * @reg    - register at which to start reading
+ * @length - length of block to read, in bytes
+ * @values - buffer to store values read from registers
+ *
+ * Returns negative errno, else number of bytes read.
+ *
+ * Note: The trackpad register block is 256 bytes.
+ */
+static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
+					u8 *values)
+{
+	struct device *dev = &cyapa->client->dev;
+	ssize_t ret;
+
+	ret = i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
+	dev_dbg(dev, "i2c read block reg: 0x%02x len: %zu ret: %zd\n",
+		reg, len, ret);
+	if (ret > 0)
+		cyapa_dump_data(cyapa, ret, values);
+
+	return ret;
+}
+
+/*
+ * cyapa_i2c_reg_write_block - write a block of data to device i2c registers
+ * @cyapa  - private data structure of driver
+ * @reg    - register at which to start writing
+ * @length - length of block to write, in bytes
+ * @values - buffer to write to i2c registers
+ *
+ * Returns 0 on success, else negative errno on failure.
+ *
+ * Note: The trackpad register block is 256 bytes.
+ */
+static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
+					 size_t len, const u8 *values)
+{
+	struct device *dev = &cyapa->client->dev;
+	ssize_t ret;
+
+	ret = i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
+	dev_dbg(dev, "i2c write block reg: 0x%02x len: %zu ret: %zd\n",
+		reg, len, ret);
+	cyapa_dump_data(cyapa, len, values);
+
+	return ret;
+}
+
+static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 cmd;
+
+	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+	ret = i2c_smbus_read_byte_data(cyapa->client, cmd);
+	dev_dbg(dev, "read byte [0x%02x] = 0x%02x  ret: %d\n",
+		cmd, ret, ret);
+
+	return ret;
+}
+
+static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 cmd;
+
+	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+	ret = i2c_smbus_write_byte_data(cyapa->client, cmd, value);
+	dev_dbg(dev, "write byte [0x%02x] = 0x%02x  ret: %d\n",
+		cmd, value, ret);
+
+	return ret;
+}
+
+static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
+{
+	u8 cmd;
+	size_t len;
+
+	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+	len = cyapa_i2c_cmds[cmd_idx].len;
+	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
+}
+
+/*
+ * Query device for its current operating state.
+ *
+ * Possible states are:
+ *   OPERATION_MODE
+ *   BOOTLOADER_IDLE
+ *   BOOTLOADER_ACTIVE
+ *   BOOTLOADER_BUSY
+ *   NO_DEVICE
+ *
+ * Returns:
+ *   0 on success, and sets cyapa->state
+ *   < 0 on error, and sets cyapa->state = CYAPA_STATE_NO_DEVICE
+ */
+static int cyapa_get_state(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 status[BL_STATUS_SIZE];
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+
+	/*
+	 * Get trackpad status by reading 3 registers starting from 0.
+	 * If the device is in the bootloader, this will be BL_HEAD.
+	 * If the device is in operation mode, this will be the DATA regs.
+	 *
+	 */
+	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
+				       status);
+	if (ret != BL_STATUS_SIZE)
+		return (ret < 0) ? ret : -EAGAIN;
+
+	if ((status[REG_OP_STATUS] & OP_STATUS_DEV) == CYAPA_DEV_NORMAL) {
+		dev_dbg(dev, "device state: operational mode\n");
+		cyapa->state = CYAPA_STATE_OP;
+	} else if (status[REG_BL_STATUS] & BL_STATUS_BUSY) {
+		dev_dbg(dev, "device state: bootloader busy\n");
+		cyapa->state = CYAPA_STATE_BL_BUSY;
+	} else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING) {
+		dev_dbg(dev, "device state: bootloader active\n");
+		cyapa->state = CYAPA_STATE_BL_ACTIVE;
+	} else {
+		dev_dbg(dev, "device state: bootloader idle\n");
+		cyapa->state = CYAPA_STATE_BL_IDLE;
+	}
+
+	return 0;
+}
+/*
+ * Poll device for its status in a loop, waiting up to timeout for a response.
+ *
+ * When the device switches state, it usually takes ~300 ms.
+ * Howere, when running a new firmware image, the device must calibrate its
+ * sensors, which can take as long as 2 seconds.
+ *
+ * Note: The timeout has granularity of the polling rate, which is 300 ms.
+ *
+ * Returns:
+ *   0 when the device eventually responds with a valid non-busy state.
+ *   -ETIMEDOUT if device never responds (too many -EAGAIN)
+ *   < 0    other errors
+ */
+static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
+{
+	int ret;
+	int tries = timeout / 100;
+
+	ret = cyapa_get_state(cyapa);
+	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
+		msleep(100);
+		ret = cyapa_get_state(cyapa);
+	}
+	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
+}
+
+/*
+ * Enter bootloader by soft resetting the device.
+ *
+ * If device is already in the bootloader, the function just returns.
+ * Otherwise, reset the device; after reset, device enters bootloader idle
+ * state immediately.
+ *
+ * Also, if device was unregister device from input core.  Device will
+ * re-register after it is detected following resumption of operational mode.
+ *
+ * Returns:
+ *   0 on success
+ *   -EAGAIN  device was reset, but is not now in bootloader idle state
+ *   < 0 if the device never responds within the timeout
+ */
+static int cyapa_bl_enter(struct cyapa *cyapa)
+{
+	int ret;
+
+	if (cyapa->input) {
+		disable_irq(cyapa->irq);
+		input_unregister_device(cyapa->input);
+		cyapa->input = NULL;
+	}
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return 0;
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+	ret = cyapa_write_byte(cyapa, CYAPA_CMD_SOFT_RESET, 0x01);
+	if (ret < 0)
+		return -EIO;
+
+	usleep_range(25000, 50000);
+	ret = cyapa_get_state(cyapa);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_BL_IDLE)
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int cyapa_bl_activate(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_activate),
+					bl_activate);
+	if (ret < 0)
+		return ret;
+
+	/* Wait for bootloader to activate; takes between 2 and 12 seconds */
+	msleep(2000);
+	ret = cyapa_poll_state(cyapa, 10000);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_BL_ACTIVE)
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int cyapa_bl_deactivate(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
+					bl_deactivate);
+	if (ret < 0)
+		return ret;
+
+	/* wait for bootloader to switch to idle state; should take < 100ms */
+	msleep(100);
+	ret = cyapa_poll_state(cyapa, 500);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_BL_IDLE)
+		return -EAGAIN;
+	return 0;
+}
+
+/*
+ * Exit bootloader
+ *
+ * Send bl_exit command, then wait 300 ms to let device transition to
+ * operational mode.  If this is the first time the device's firmware is
+ * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
+ * the device's new state for up to 2 seconds.
+ *
+ * Returns:
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
+ *   0       device is supported and in operational mode
+ */
+static int cyapa_bl_exit(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Wait for bootloader to exit, and operation mode to start.
+	 * Normally, this takes at least 50 ms.
+	 */
+	usleep_range(50000, 100000);
+	/*
+	 * In addition, when a device boots for the first time after being
+	 * updated to new firmware, it must first calibrate its sensors, which
+	 * can take up to an additional 2 seconds.
+	 */
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EAGAIN;
+
+	return 0;
+}
+
+/*
+ * Set device power mode
+ *
+ * Write to the field to configure power state. Power states include :
+ *   Full : Max scans and report rate.
+ *   Idle : Report rate set by user specified time.
+ *   ButtonOnly : No scans for fingers. When the button is triggered,
+ *     a slave interrupt is asserted to notify host to wake up.
+ *   Off : Only awake for i2c commands from host. No function for button
+ *     or touch sensors.
+ *
+ * The power_mode command should conform to the following :
+ *   Full : 0x3f
+ *   Idle : Configurable from 20 to 1000ms. See note below for
+ *     cyapa_sleep_time_to_pwr_cmd and cyapa_pwr_cmd_to_sleep_time
+ *   ButtonOnly : 0x01
+ *   Off : 0x00
+ *
+ * Device power mode can only be set when device is in operational mode.
+ */
+static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 power;
+	int tries = SET_POWER_MODE_TRIES;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return 0;
+
+	while (true) {
+		ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
+		if (ret >= 0 || --tries < 1)
+			break;
+		dev_dbg(dev, "set power mode read retry. tries left = %d\n",
+			tries);
+		usleep_range(SET_POWER_MODE_DELAY, 2 * SET_POWER_MODE_DELAY);
+	}
+	if (ret < 0) {
+		dev_err(dev, "failed to read power mode %d\n", ret);
+		return ret;
+	}
+
+	power = ret;
+	power &= ~PWR_MODE_MASK;
+	power |= power_mode & PWR_MODE_MASK;
+	while (true) {
+		ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
+		if (!ret || --tries < 1)
+			break;
+		dev_dbg(dev, "set power mode write retry. tries left = %d\n",
+			tries);
+		usleep_range(SET_POWER_MODE_DELAY, 2 * SET_POWER_MODE_DELAY);
+	}
+	if (ret < 0)
+		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
+			power_mode, ret);
+	return ret;
+}
+
+static int cyapa_get_query_data(struct cyapa *cyapa)
+{
+	u8 query_data[QUERY_DATA_SIZE];
+	int ret;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EBUSY;
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
+	if (ret < 0)
+		return ret;
+	if (ret != QUERY_DATA_SIZE)
+		return -EIO;
+
+	memcpy(&cyapa->product_id[0], &query_data[0], 5);
+	cyapa->product_id[5] = '-';
+	memcpy(&cyapa->product_id[6], &query_data[5], 6);
+	cyapa->product_id[12] = '-';
+	memcpy(&cyapa->product_id[13], &query_data[11], 2);
+	cyapa->product_id[15] = '\0';
+
+	cyapa->fw_maj_ver = query_data[15];
+	cyapa->fw_min_ver = query_data[16];
+	cyapa->hw_maj_ver = query_data[17];
+	cyapa->hw_min_ver = query_data[18];
+
+	cyapa->gen = query_data[20] & 0x0f;
+
+	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
+	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
+
+	cyapa->physical_size_x =
+		((query_data[24] & 0xf0) << 4) | query_data[25];
+	cyapa->physical_size_y =
+		((query_data[24] & 0x0f) << 8) | query_data[26];
+
+	return 0;
+}
+
+/*
+ * Check if device is operational.
+ *
+ * An operational device is responding, has exited bootloader, and has
+ * firmware supported by this driver.
+ *
+ * Returns:
+ *   -EBUSY  no device or in bootloader
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is still in bootloader
+ *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
+ *   -EINVAL device is in operational mode, but not supported by this driver
+ *   0       device is supported
+ */
+static int cyapa_check_is_operational(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	const char unique_str[] = "CYTRA";
+	int ret;
+
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	switch (cyapa->state) {
+	case CYAPA_STATE_BL_ACTIVE:
+		ret = cyapa_bl_deactivate(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_BL_IDLE:
+		ret = cyapa_bl_exit(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_OP:
+		ret = cyapa_get_query_data(cyapa);
+		if (ret < 0)
+			return ret;
+
+		/* only support firmware protocol gen3 */
+		if (cyapa->gen != CYAPA_GEN3) {
+			dev_err(dev, "unsupported protocol version (%d)",
+				cyapa->gen);
+			return -EINVAL;
+		}
+
+		/* only support product ID starting with CYTRA */
+		if (memcmp(cyapa->product_id, unique_str,
+			   sizeof(unique_str) - 1)) {
+			dev_err(dev, "unsupported product ID (%s)\n",
+				cyapa->product_id);
+			return -EINVAL;
+		}
+		return 0;
+
+	default:
+		return -EIO;
+	}
+	return 0;
+}
+
+static u16 cyapa_csum(const u8 *buf, size_t count)
+{
+	int i;
+	u16 csum = 0;
+
+	for (i = 0; i < count; i++)
+		csum += buf[i];
+
+	return csum;
+}
+
+/*
+ * Write a |len| byte long buffer |buf| to the device, by chopping it up into a
+ * sequence of smaller |CYAPA_CMD_LEN|-length write commands.
+ *
+ * The data bytes for a write command are prepended with the 1-byte offset
+ * of the data relative to the start of |buf|.
+ */
+static int cyapa_write_buffer(struct cyapa *cyapa, const u8 *buf, size_t len)
+{
+	int ret;
+	size_t i;
+	unsigned char cmd[CYAPA_CMD_LEN + 1];
+	size_t cmd_len;
+
+	for (i = 0; i < len; i += CYAPA_CMD_LEN) {
+		const u8 *payload = &buf[i];
+		cmd_len = (len - i >= CYAPA_CMD_LEN) ? CYAPA_CMD_LEN : len - i;
+		cmd[0] = i;
+		memcpy(&cmd[1], payload, cmd_len);
+
+		ret = cyapa_i2c_reg_write_block(cyapa, 0, cmd_len + 1, cmd);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+/*
+ * A firmware block write command writes 64 bytes of data to a single flash
+ * page in the device.  The 78-byte block write command has the format:
+ *   <0xff> <CMD> <Key> <Start> <Data> <Data-Checksum> <CMD Checksum>
+ *
+ *  <0xff>  - every command starts with 0xff
+ *  <CMD>   - the write command value is 0x39
+ *  <Key>   - write commands include an 8-byte key: { 00 01 02 03 04 05 06 07 }
+ *  <Block> - Memory Block number (address / 64) (16-bit, big-endian)
+ *  <Data>  - 64 bytes of firmware image data
+ *  <Data Checksum> - sum of 64 <Data> bytes, modulo 0xff
+ *  <CMD Checksum> - sum of 77 bytes, from 0xff to <Data Checksum>
+ *
+ * Each write command is split into 5 i2c write transactions of up to 16 bytes.
+ * Each transaction starts with an i2c register offset: (00, 10, 20, 30, 40).
+ */
+static int cyapa_write_fw_block(struct cyapa *cyapa, u16 block, const u8 *data)
+{
+	int ret;
+	u8 cmd[78];
+	u8 status[BL_STATUS_SIZE];
+	int tries = 3;
+
+	/* set write command and security key bytes. */
+	cmd[0] = 0xff;
+	cmd[1] = 0x39;
+	cmd[2] = 0x00;
+	cmd[3] = 0x01;
+	cmd[4] = 0x02;
+	cmd[5] = 0x03;
+	cmd[6] = 0x04;
+	cmd[7] = 0x05;
+	cmd[8] = 0x06;
+	cmd[9] = 0x07;
+	cmd[10] = block >> 8;
+	cmd[11] = block;
+	memcpy(&cmd[12], data, CYAPA_FW_BLOCK_SIZE);
+	cmd[76] = cyapa_csum(data, CYAPA_FW_BLOCK_SIZE);
+	cmd[77] = cyapa_csum(cmd, sizeof(cmd) - 1);
+
+	ret = cyapa_write_buffer(cyapa, cmd, sizeof(cmd));
+	if (ret)
+		return ret;
+
+	/* wait for write to finish */
+	do {
+		usleep_range(10000, 20000);
+
+		/* check block write command result status. */
+		ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET,
+					       BL_STATUS_SIZE, status);
+		if (ret != BL_STATUS_SIZE)
+			return (ret < 0) ? ret : -EIO;
+		ret = (status[1] == 0x10 && status[2] == 0x20) ? 0 : -EIO;
+	} while (--tries && ret);
+
+	return ret;
+}
+
+/*
+ * Verify the integrity of a CYAPA firmware image file.
+ *
+ * The firmware image file is 30848 bytes, composed of 482 64-byte blocks.
+ *
+ * The first 2 blocks are the firmware header.
+ * The next 480 blocks are the firmware image.
+ *
+ * The first two bytes of the header hold the header checksum, computed by
+ * summing the other 126 bytes of the header.
+ * The last two bytes of the header hold the firmware image checksum, computed
+ * by summing the 30720 bytes of the image modulo 0xffff.
+ *
+ * Both checksums are stored little-endian.
+ */
+static int cyapa_check_fw(struct cyapa *cyapa, const struct firmware *fw)
+{
+	struct device *dev = &cyapa->client->dev;
+	u16 csum;
+	u16 csum_expected;
+
+	/* Firmware must match exact 30848 bytes = 482 64-byte blocks. */
+	if (fw->size != CYAPA_FW_SIZE) {
+		dev_err(dev, "invalid firmware size = %zu, expected %u.\n",
+			fw->size, CYAPA_FW_SIZE);
+		return -EINVAL;
+	}
+
+	/* Verify header block */
+	csum_expected = (fw->data[0] << 8) | fw->data[1];
+	csum = cyapa_csum(&fw->data[2], CYAPA_FW_HDR_SIZE - 2);
+	if (csum != csum_expected) {
+		dev_err(dev, "invalid firmware header checksum = %04x,", csum);
+		dev_err(dev, " expected: %04x\n", csum_expected);
+		return -EINVAL;
+	}
+
+	/* Verify firmware image */
+	csum_expected = (fw->data[CYAPA_FW_HDR_SIZE - 2] << 8) |
+			 fw->data[CYAPA_FW_HDR_SIZE - 1];
+	csum = cyapa_csum(&fw->data[CYAPA_FW_HDR_SIZE], CYAPA_FW_DATA_SIZE);
+	if (csum != csum_expected) {
+		dev_err(dev, "invalid firmware checksum = %04x,", csum);
+		dev_err(dev, " expected: %04x\n", csum_expected);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int cyapa_firmware(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	const struct firmware *fw;
+	const char *fw_name = CYAPA_FW_NAME;
+	int i;
+
+	ret = request_firmware(&fw, CYAPA_FW_NAME, dev);
+	if (ret) {
+		dev_err(dev, "Could not load firmware from %s, %d\n",
+			  fw_name, ret);
+		return ret;
+	}
+
+	ret = cyapa_check_fw(cyapa, fw);
+	if (ret) {
+		dev_err(dev, "Invalid CYAPA firmware image: %s\n", fw_name);
+		goto done;
+	}
+
+	ret = cyapa_bl_enter(cyapa);
+	if (ret)
+		goto err_detect;
+
+	ret = cyapa_bl_activate(cyapa);
+	if (ret)
+		goto err_detect;
+
+	/* First write data, starting at byte 128  of fw->data */
+	for (i = 0; i < CYAPA_FW_DATA_BLOCK_COUNT; i++) {
+		size_t block = CYAPA_FW_DATA_BLOCK_START + i;
+		size_t addr = (i + CYAPA_FW_HDR_BLOCK_COUNT) *
+				CYAPA_FW_BLOCK_SIZE;
+		const u8 *data = &fw->data[addr];
+		ret = cyapa_write_fw_block(cyapa, block, data);
+		if (ret)
+			goto err_detect;
+	}
+
+	/* Then write checksum */
+	for (i = 0; i < CYAPA_FW_HDR_BLOCK_COUNT; i++) {
+		size_t block = CYAPA_FW_HDR_BLOCK_START + i;
+		size_t addr = i * CYAPA_FW_BLOCK_SIZE;
+		const u8 *data = &fw->data[addr];
+		ret = cyapa_write_fw_block(cyapa, block, data);
+		if (ret)
+			goto err_detect;
+	}
+
+err_detect:
+	cyapa_detect(cyapa);
+
+done:
+	release_firmware(fw);
+	return ret;
+}
+
+/*
+ *******************************************************************
+ *	Sysfs Interface.
+ *******************************************************************
+ */
+static ssize_t cyapa_show_fm_ver(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%d.%d\n", cyapa->fw_maj_ver,
+			 cyapa->fw_min_ver);
+}
+
+static ssize_t cyapa_show_hw_ver(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%d.%d\n", cyapa->hw_maj_ver,
+			 cyapa->hw_min_ver);
+}
+
+static ssize_t cyapa_show_product_id(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%s\n", cyapa->product_id);
+}
+
+static ssize_t cyapa_show_protocol_version(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	return scnprintf(buf, PAGE_SIZE, "%d\n", cyapa->gen);
+}
+
+static ssize_t cyapa_update_fw_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	int ret;
+
+	ret = cyapa_firmware(cyapa);
+	if (ret)
+		dev_err(dev, "firmware update failed, %d\n", ret);
+	else
+		dev_dbg(dev, "firmware update succeeded\n");
+
+	return ret ? ret : count;
+}
+
+/*
+ * cyapa_sleep_time_to_pwr_cmd and cyapa_pwr_cmd_to_sleep_time
+ *
+ * These are helper functions that convert to and from integer idle
+ * times and register settings to write to the PowerMode register.
+ * The trackpad supports between 20ms to 1000ms scan intervals.
+ * The time will be increased in increments of 10ms from 20ms to 100ms.
+ * From 100ms to 1000ms, time will be increased in increments of 20ms.
+ *
+ * When Idle_Time < 100, the format to convert Idle_Time to Idle_Command is:
+ *   Idle_Command = Idle Time / 10;
+ * When Idle_Time >= 100, the format to convert Idle_Time to Idle_Command is:
+ *   Idle_Command = Idle Time / 20 + 5;
+ */
+static u8 cyapa_sleep_time_to_pwr_cmd(u16 sleep_time)
+{
+	if (sleep_time < 20)
+		sleep_time = 20;     /* minimal sleep time. */
+	else if (sleep_time > 1000)
+		sleep_time = 1000;   /* maximal sleep time. */
+
+	if (sleep_time < 100)
+		return ((sleep_time / 10) << 2) & PWR_MODE_MASK;
+	else
+		return ((sleep_time / 20 + 5) << 2) & PWR_MODE_MASK;
+}
+
+static u16 cyapa_pwr_cmd_to_sleep_time(u8 pwr_mode)
+{
+	u8 encoded_time = pwr_mode >> 2;
+	return (encoded_time < 10) ? encoded_time * 10
+				   : (encoded_time - 5) * 20;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static ssize_t cyapa_show_suspend_scanrate(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	int len;
+	u8 pwr_cmd = cyapa->suspend_power_mode;
+
+	if (pwr_cmd == PWR_MODE_BTN_ONLY)
+		len = scnprintf(buf, PAGE_SIZE, "%s\n", BTN_ONLY_MODE_NAME);
+	else
+		len = scnprintf(buf, PAGE_SIZE, "%u\n",
+				cyapa_pwr_cmd_to_sleep_time(pwr_cmd));
+	return len;
+}
+
+static ssize_t cyapa_update_suspend_scanrate(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count)
+{
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+	u8 pwr_cmd;
+	u16 sleep_time;
+
+	if (buf == NULL || count == 0)
+		goto invalidparam;
+
+	if (sysfs_streq(buf, BTN_ONLY_MODE_NAME))
+		pwr_cmd = PWR_MODE_BTN_ONLY;
+	else if (!kstrtou16(buf, 10, &sleep_time))
+		pwr_cmd = cyapa_sleep_time_to_pwr_cmd(sleep_time);
+	else
+		goto invalidparam;
+
+	cyapa->suspend_power_mode = pwr_cmd;
+	return count;
+
+invalidparam:
+	dev_err(dev, "invalid suspend scanrate ms parameters\n");
+	return -EINVAL;
+}
+
+static DEVICE_ATTR(suspend_scanrate_ms, S_IRUGO|S_IWUSR,
+		   cyapa_show_suspend_scanrate,
+		   cyapa_update_suspend_scanrate);
+
+static struct attribute *cyapa_power_wakeup_entries[] = {
+	&dev_attr_suspend_scanrate_ms.attr,
+	NULL,
+};
+
+static const struct attribute_group cyapa_power_wakeup_group = {
+	.name = power_group_name,
+	.attrs = cyapa_power_wakeup_entries,
+};
+#endif /* CONFIG_PM_SLEEP */
+
+static DEVICE_ATTR(firmware_version, S_IRUGO, cyapa_show_fm_ver, NULL);
+static DEVICE_ATTR(hardware_version, S_IRUGO, cyapa_show_hw_ver, NULL);
+static DEVICE_ATTR(product_id, S_IRUGO, cyapa_show_product_id, NULL);
+static DEVICE_ATTR(protocol_version, S_IRUGO, cyapa_show_protocol_version,
+		   NULL);
+static DEVICE_ATTR(update_fw, S_IWUSR, NULL, cyapa_update_fw_store);
+
+static struct attribute *cyapa_sysfs_entries[] = {
+	&dev_attr_firmware_version.attr,
+	&dev_attr_hardware_version.attr,
+	&dev_attr_product_id.attr,
+	&dev_attr_protocol_version.attr,
+	&dev_attr_update_fw.attr,
+	NULL,
+};
+
+static const struct attribute_group cyapa_sysfs_group = {
+	.attrs = cyapa_sysfs_entries,
+};
+
+/*
+ **************************************************************
+ * Cypress APA trackpad with I2C interface input device driver.
+ **************************************************************
+ */
+
+static irqreturn_t cyapa_irq(int irq, void *dev_id)
+{
+	struct cyapa *cyapa = dev_id;
+	struct device *dev = &cyapa->client->dev;
+	struct input_dev *input = cyapa->input;
+	struct cyapa_reg_data data;
+	int i;
+	int ret;
+	int num_fingers;
+	unsigned int mask;
+
+	/*
+	 * Don't read input if input device has not been configured.
+	 * This check check solves a race during probe() between irq_request()
+	 * and irq_disable(), since there is no way to request an irq that is
+	 * initially disabled.
+	 */
+	if (!input)
+		return IRQ_HANDLED;
+
+	if (device_may_wakeup(dev))
+		pm_wakeup_event(dev, 0);
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
+	if (ret != sizeof(data))
+		return IRQ_HANDLED;
+
+	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
+	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
+	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
+		return IRQ_HANDLED;
+	}
+
+	mask = 0;
+	num_fingers = (data.finger_btn >> 4) & 0x0f;
+	for (i = 0; i < num_fingers; i++) {
+		const struct cyapa_touch *touch = &data.touches[i];
+		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
+		int slot = touch->id - 1;
+
+		mask |= (1 << slot);
+		input_mt_slot(input, slot);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+		input_report_abs(input, ABS_MT_POSITION_X,
+				 ((touch->xy & 0xf0) << 4) | touch->x);
+		input_report_abs(input, ABS_MT_POSITION_Y,
+				 ((touch->xy & 0x0f) << 8) | touch->y);
+		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
+	}
+
+	/* Invalidate all unreported slots */
+	for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
+		if (mask & (1 << i))
+			continue;
+		input_mt_slot(input, i);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
+	}
+
+	input_mt_report_pointer_emulation(input, true);
+	input_report_key(input, BTN_LEFT, data.finger_btn & OP_DATA_BTN_MASK);
+	input_sync(input);
+
+	return IRQ_HANDLED;
+}
+
+static int cyapa_create_input_dev(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	struct input_dev *input;
+
+	dev_info(dev,
+		 "Cypress APA Trackpad Information:\n" \
+		 "    Product ID:  %s\n" \
+		 "    Protocol Generation:  %d\n" \
+		 "    Firmware Version:  %d.%d\n" \
+		 "    Hardware Version:  %d.%d\n" \
+		 "    Max ABS X,Y:   %d,%d\n" \
+		 "    Physical Size X,Y:   %d,%d\n",
+		 cyapa->product_id,
+		 cyapa->gen,
+		 cyapa->fw_maj_ver, cyapa->fw_min_ver,
+		 cyapa->hw_maj_ver, cyapa->hw_min_ver,
+		 cyapa->max_abs_x, cyapa->max_abs_y,
+		 cyapa->physical_size_x, cyapa->physical_size_y);
+
+	input = cyapa->input = input_allocate_device();
+	if (!input) {
+		dev_err(dev, "allocate memory for input device failed\n");
+		return -ENOMEM;
+	}
+
+	input->name = CYAPA_NAME;
+	input->phys = cyapa->phys;
+	input->id.bustype = BUS_I2C;
+	input->id.version = 1;
+	input->id.product = 0;  /* means any product in eventcomm. */
+	input->dev.parent = &cyapa->client->dev;
+
+	input_set_drvdata(input, cyapa);
+
+	__set_bit(EV_ABS, input->evbit);
+
+	/*
+	 * set and report not-MT axes to support synaptics X Driver.
+	 * When multi-fingers on trackpad, only the first finger touch
+	 * will be reported as X/Y axes values.
+	 */
+	input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
+
+	/* finger position */
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
+	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
+	if (ret < 0) {
+		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
+		goto err_free_device;
+	}
+
+	if (cyapa->physical_size_x && cyapa->physical_size_y) {
+		input_abs_set_res(input, ABS_X,
+			cyapa->max_abs_x / cyapa->physical_size_x);
+		input_abs_set_res(input, ABS_Y,
+			cyapa->max_abs_y / cyapa->physical_size_y);
+		input_abs_set_res(input, ABS_MT_POSITION_X,
+			cyapa->max_abs_x / cyapa->physical_size_x);
+		input_abs_set_res(input, ABS_MT_POSITION_Y,
+			cyapa->max_abs_y / cyapa->physical_size_y);
+	}
+
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(BTN_TOUCH, input->keybit);
+	__set_bit(BTN_TOOL_FINGER, input->keybit);
+	__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
+	__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
+	__set_bit(BTN_TOOL_QUADTAP, input->keybit);
+	__set_bit(BTN_TOOL_QUINTTAP, input->keybit);
+
+	__set_bit(BTN_LEFT, input->keybit);
+
+	__set_bit(INPUT_PROP_POINTER, input->propbit);
+	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
+
+	/* Register the device in input subsystem */
+	ret = input_register_device(input);
+	if (ret) {
+		dev_err(dev, "input device register failed, %d\n", ret);
+		goto err_free_device;
+	}
+
+	enable_irq(cyapa->irq);
+	return 0;
+
+err_free_device:
+	input_free_device(input);
+	cyapa->input = NULL;
+	return ret;
+}
+
+static void cyapa_detect(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+
+	ret = cyapa_check_is_operational(cyapa);
+	if (ret == -ETIMEDOUT) {
+		dev_err(dev, "no device detected, %d\n", ret);
+		return;
+	} else if (ret) {
+		dev_err(dev, "device detected, but not operational, %d\n", ret);
+		return;
+	}
+
+	if (!cyapa->input) {
+		ret = cyapa_create_input_dev(cyapa);
+		if (ret)
+			dev_err(dev, "create input_dev instance failed, %d\n",
+				ret);
+
+		/*
+		 * On some systems, a system crash / warm boot does not reset
+		 * the device's current power mode to FULL_ACTIVE.
+		 * If such an event happens during suspend, after the device
+		 * has been put in a low power mode, the device will still be
+		 * in low power mode on a subsequent boot, since there was
+		 * never a matching resume().
+		 * Handle this by always forcing full power here, when a
+		 * device is first detected to be in operational mode.
+		 */
+		ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+		if (ret)
+			dev_warn(dev, "set active power failed, %d\n", ret);
+	}
+}
+
+static int __devinit cyapa_probe(struct i2c_client *client,
+				 const struct i2c_device_id *dev_id)
+{
+	int ret;
+	struct cyapa *cyapa;
+	struct device *dev = &client->dev;
+
+	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
+	if (!cyapa) {
+		dev_err(dev, "allocate memory for cyapa failed\n");
+		return -ENOMEM;
+	}
+
+	cyapa->gen = CYAPA_GEN3;
+	cyapa->client = client;
+	i2c_set_clientdata(client, cyapa);
+	cyapa->phys = kasprintf(GFP_KERNEL, "i2c-%d-%04x/input0",
+				client->adapter->nr, client->addr);
+	if (!cyapa->phys) {
+		ret = -ENOMEM;
+		goto err_mem_free;
+	}
+
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+	cyapa->suspend_power_mode = PWR_MODE_IDLE;
+
+	/*
+	 * Note: There is no way to request an irq that is initially disabled.
+	 * Thus, there is a little race here, which is resolved in cyapa_irq()
+	 * by checking that cyapa->input has been allocated, which happens
+	 * in cyapa_detect(), before creating input events.
+	 */
+	cyapa->irq = client->irq;
+	ret = request_threaded_irq(cyapa->irq,
+				   NULL,
+				   cyapa_irq,
+				   IRQF_TRIGGER_FALLING,
+				   "cyapa",
+				   cyapa);
+	if (ret) {
+		dev_err(dev, "IRQ request failed: %d\n, ", ret);
+		goto err_mem_free;
+	}
+	disable_irq(cyapa->irq);
+
+	if (sysfs_create_group(&client->dev.kobj, &cyapa_sysfs_group))
+		dev_warn(dev, "error creating sysfs entries.\n");
+
+#ifdef CONFIG_PM_SLEEP
+	if (device_can_wakeup(dev) &&
+	    sysfs_merge_group(&client->dev.kobj, &cyapa_power_wakeup_group))
+		dev_warn(dev, "error creating wakeup power entries.\n");
+#endif /* CONFIG_PM_SLEEP */
+
+	cyapa_detect(cyapa);
+
+	return 0;
+
+err_mem_free:
+	kfree(cyapa->phys);
+	kfree(cyapa);
+
+	return ret;
+}
+
+static int __devexit cyapa_remove(struct i2c_client *client)
+{
+	struct cyapa *cyapa = i2c_get_clientdata(client);
+
+	sysfs_remove_group(&client->dev.kobj, &cyapa_sysfs_group);
+
+	free_irq(cyapa->irq, cyapa);
+
+	if (cyapa->input)
+		input_unregister_device(cyapa->input);
+
+	kfree(cyapa->phys);
+	kfree(cyapa);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cyapa_suspend(struct device *dev)
+{
+	int ret;
+	u8 power_mode;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	/* set trackpad device to idle mode if wakeup is allowed
+	 * otherwise turn off. */
+	power_mode = device_may_wakeup(dev) ? cyapa->suspend_power_mode
+					    : PWR_MODE_OFF;
+	ret = cyapa_set_power_mode(cyapa, power_mode);
+	if (ret < 0)
+		dev_err(dev, "set power mode failed, %d\n", ret);
+
+	if (device_may_wakeup(dev))
+		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
+	disable_irq(cyapa->irq);
+
+	return 0;
+}
+
+static int cyapa_resume(struct device *dev)
+{
+	int ret;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	enable_irq(cyapa->irq);
+	if (device_may_wakeup(dev) && cyapa->irq_wake)
+		disable_irq_wake(cyapa->irq);
+
+	cyapa_detect(cyapa);
+
+	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+	if (ret)
+		dev_warn(dev, "resume active power failed, %d\n", ret);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
+
+static const struct i2c_device_id cyapa_id_table[] = {
+	{ "cyapa", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
+
+static struct i2c_driver cyapa_driver = {
+	.driver = {
+		.name = "cyapa",
+		.owner = THIS_MODULE,
+		.pm = &cyapa_pm_ops,
+	},
+
+	.probe = cyapa_probe,
+	.remove = __devexit_p(cyapa_remove),
+	.id_table = cyapa_id_table,
+};
+
+module_i2c_driver(cyapa_driver);
+
+MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
+MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
+MODULE_LICENSE("GPL");
-- 
1.7.7.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH] Input: add driver for Cypress APA I2C Trackpad
  2012-07-10 22:29 [PATCH] Input: add driver for Cypress APA I2C Trackpad Benson Leung
@ 2012-07-16 11:05 ` Henrik Rydberg
  2012-12-06  0:48 ` [PATCH v2 0/1] " Benson Leung
  1 sibling, 0 replies; 14+ messages in thread
From: Henrik Rydberg @ 2012-07-16 11:05 UTC (permalink / raw)
  To: Benson Leung
  Cc: dmitry.torokhov, dudl, djkurtz, olofj, linux-input, linux-kernel

Hi Benson,

> This patch introduces a driver for Cypress All Points Addressable
> I2C Trackpad, including the one in the Samsung Series 5 550 Chromebook.
> 
> This device is compatible with MT protocol type B, providing identifiable
> contacts.
> 
> This driver also implements firmware updating capability via
> request_firmware.
> 
> Signed-off-by: Dudley Du <dudl@cypress.com>
> Signed-off-by: Benson Leung <bleung@chromium.org>
> ---

Thanks for the driver, please find some comments inline.

>  drivers/input/mouse/Kconfig  |   13 +
>  drivers/input/mouse/Makefile |    1 +
>  drivers/input/mouse/cyapa.c  | 1493 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 1507 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/input/mouse/cyapa.c
> 
> diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
> index cd6268c..2767c3c 100644
> --- a/drivers/input/mouse/Kconfig
> +++ b/drivers/input/mouse/Kconfig
> @@ -193,6 +193,19 @@ config MOUSE_BCM5974
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called bcm5974.
>  
> +config MOUSE_CYAPA
> +	tristate "Cypress APA I2C Trackpad support"
> +	depends on I2C
> +	help
> +	  This driver add support for Cypress All Points Addressable (APA)

"adds"

> +	  I2C Trackpads, including the one in the Samsung Series 5 550
> +	  Chromebook.
> +
> +	  Say Y here if you have a Cypress APA I2C Trackpad.
> +
> +	  To compile this driver as a module, choose M here: the module will be
> +	  called cyapa.
> +
>  config MOUSE_INPORT
>  	tristate "InPort/MS/ATIXL busmouse"
>  	depends on ISA
> diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
> index 46ba755..10b4773 100644
> --- a/drivers/input/mouse/Makefile
> +++ b/drivers/input/mouse/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
>  obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
>  obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
>  obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
> +obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
>  obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
>  obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
>  obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
> diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
> new file mode 100644
> index 0000000..8af0970
> --- /dev/null
> +++ b/drivers/input/mouse/cyapa.c
> @@ -0,0 +1,1493 @@
> +/*
> + * Cypress APA trackpad with I2C interface
> + *
> + * Author: Dudley Du <dudl@cypress.com>
> + * Further cleanup and restructuring by:
> + *   Daniel Kurtz <djkurtz@chromium.org>
> + *   Benson Leung <bleung@chromium.org>
> + *
> + * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
> + * Copyright (C) 2011-2012 Google, Inc.
> + *
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License.  See the file COPYING in the main directory of this archive for
> + * more details.
> + */
> +
> +
> +#include <linux/delay.h>
> +#include <linux/firmware.h>
> +#include <linux/gpio.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/input/mt.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/semaphore.h>
> +#include <linux/slab.h>
> +#include <linux/uaccess.h>
> +
> +/* APA trackpad firmware generation */
> +enum cyapa_gen {
> +	CYAPA_GEN1 = 0x01,  /* only one finger supported. */
> +	CYAPA_GEN2 = 0x02,  /* max five fingers supported. */
> +	CYAPA_GEN3 = 0x03,  /* support MT-protocol B with tracking ID. */
> +};

If the firmware reports a value not in this list, the enum benefit of
a closed set is lost. Please define the values actually used instead.

> +
> +#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
> +
> +/* commands for read/write registers of Cypress trackpad */
> +#define CYAPA_CMD_SOFT_RESET       0x00
> +#define CYAPA_CMD_POWER_MODE       0x01
> +#define CYAPA_CMD_DEV_STATUS       0x02
> +#define CYAPA_CMD_GROUP_DATA       0x03
> +#define CYAPA_CMD_GROUP_CTRL       0x04
> +#define CYAPA_CMD_GROUP_CMD        0x05
> +#define CYAPA_CMD_GROUP_QUERY      0x06
> +#define CYAPA_CMD_BL_STATUS        0x07
> +#define CYAPA_CMD_BL_HEAD          0x08
> +#define CYAPA_CMD_BL_CMD           0x09
> +#define CYAPA_CMD_BL_DATA          0x0a
> +#define CYAPA_CMD_BL_ALL           0x0b
> +#define CYAPA_CMD_BLK_PRODUCT_ID   0x0c
> +#define CYAPA_CMD_BLK_HEAD         0x0d
> +
> +/* report data start reg offset address. */
> +#define DATA_REG_START_OFFSET  0x0000
> +
> +#define BL_HEAD_OFFSET 0x00
> +#define BL_DATA_OFFSET 0x10
> +
> +/*
> + * Operational Device Status Register
> + *
> + * bit 7: Valid interrupt source
> + * bit 6 - 4: Reserved
> + * bit 3 - 2: Power status
> + * bit 1 - 0: Device status
> + */
> +#define REG_OP_STATUS     0x00
> +#define OP_STATUS_SRC     0x80
> +#define OP_STATUS_POWER   0x0c
> +#define OP_STATUS_DEV     0x03
> +#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
> +
> +/*
> + * Operational Finger Count/Button Flags Register
> + *
> + * bit 7 - 4: Number of touched finger
> + * bit 3: Valid data
> + * bit 2: Middle Physical Button
> + * bit 1: Right Physical Button
> + * bit 0: Left physical Button
> + */
> +#define REG_OP_DATA1       0x01
> +#define OP_DATA_VALID      0x08
> +#define OP_DATA_MIDDLE_BTN 0x04
> +#define OP_DATA_RIGHT_BTN  0x02
> +#define OP_DATA_LEFT_BTN   0x01
> +#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
> +			  OP_DATA_LEFT_BTN)
> +
> +/*
> + * Bootloader Status Register
> + *
> + * bit 7: Busy
> + * bit 6 - 5: Reserved
> + * bit 4: Bootloader running
> + * bit 3 - 1: Reserved
> + * bit 0: Checksum valid
> + */
> +#define REG_BL_STATUS        0x01
> +#define BL_STATUS_BUSY       0x80
> +#define BL_STATUS_RUNNING    0x10
> +#define BL_STATUS_DATA_VALID 0x08
> +#define BL_STATUS_CSUM_VALID 0x01
> +
> +/*
> + * Bootloader Error Register
> + *
> + * bit 7: Invalid
> + * bit 6: Invalid security key
> + * bit 5: Bootloading
> + * bit 4: Command checksum
> + * bit 3: Flash protection error
> + * bit 2: Flash checksum error
> + * bit 1 - 0: Reserved
> + */
> +#define REG_BL_ERROR         0x02
> +#define BL_ERROR_INVALID     0x80
> +#define BL_ERROR_INVALID_KEY 0x40
> +#define BL_ERROR_BOOTLOADING 0x20
> +#define BL_ERROR_CMD_CSUM    0x10
> +#define BL_ERROR_FLASH_PROT  0x08
> +#define BL_ERROR_FLASH_CSUM  0x04
> +
> +#define REG_BL_KEY1 0x0d
> +#define REG_BL_KEY2 0x0e
> +#define REG_BL_KEY3 0x0f
> +#define BL_KEY1 0xc0
> +#define BL_KEY2 0xc1
> +#define BL_KEY3 0xc2
> +
> +#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
> +#define BLK_HEAD_BYTES 32
> +
> +/* Macro for register map group offset. */
> +#define CYAPA_REG_MAP_SIZE  256
> +
> +#define PRODUCT_ID_SIZE  16
> +#define QUERY_DATA_SIZE  27
> +#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
> +
> +#define REG_OFFSET_DATA_BASE     0x0000
> +#define REG_OFFSET_CONTROL_BASE  0x0000
> +#define REG_OFFSET_COMMAND_BASE  0x0028
> +#define REG_OFFSET_QUERY_BASE    0x002a
> +
> +#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
> +
> +#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
> +#define SET_POWER_MODE_DELAY   10000  /* unit: us */
> +#define SET_POWER_MODE_TRIES   5
> +
> +#define PWR_MODE_MASK   0xfc
> +#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
> +#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
> +#define PWR_MODE_BTN_ONLY    (0x01 << 2)
> +#define PWR_MODE_OFF         (0x00 << 2)
> +
> +#define BTN_ONLY_MODE_NAME   "buttononly"
> +
> +#define PWR_STATUS_MASK      0x0c
> +#define PWR_STATUS_ACTIVE    (0x03 << 2)
> +#define PWR_STATUS_IDLE      (0x02 << 2)
> +#define PWR_STATUS_BTN_ONLY  (0x01 << 2)
> +#define PWR_STATUS_OFF       (0x00 << 2)

It seems some of the values defined above are not used in the driver.

> +
> +/*
> + * CYAPA trackpad device states.
> + * Used in register 0x00, bit1-0, DeviceStatus field.
> + * After trackpad boots, and can report data, it sets this value.
> + * Other values indicate device is in an abnormal state and must be reset.
> + */
> +#define CYAPA_DEV_NORMAL  0x03
> +
> +enum cyapa_state {
> +	CYAPA_STATE_OP,
> +	CYAPA_STATE_BL_IDLE,
> +	CYAPA_STATE_BL_ACTIVE,
> +	CYAPA_STATE_BL_BUSY,
> +	CYAPA_STATE_NO_DEVICE,
> +};
> +
> +
> +struct cyapa_touch {
> +	/*
> +	 * high bits or x/y position value
> +	 * bit 7 - 4: high 4 bits of x position value
> +	 * bit 3 - 0: high 4 bits of y position value
> +	 */
> +	u8 xy;
> +	u8 x;  /* low 8 bits of x position value. */
> +	u8 y;  /* low 8 bits of y position value. */

Other recent and similar drivers use x_hi and x_lo here.

> +	u8 pressure;
> +	/* id range is 1 - 15.  It is incremented with every new touch. */
> +	u8 id;
> +} __packed;
> +
> +/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
> +#define CYAPA_MAX_MT_SLOTS  15
> +
> +/* CYAPA reports up to 5 touches per packet. */
> +#define CYAPA_MAX_TOUCHES  5

Since this is a transport protocol detail, perhaps the name should be
less generic. Alternatively, why not just use [5] below.

> +
> +struct cyapa_reg_data {
> +	/*
> +	 * bit 0 - 1: device status
> +	 * bit 3 - 2: power mode
> +	 * bit 6 - 4: reserved
> +	 * bit 7: interrupt valid bit
> +	 */
> +	u8 device_status;
> +	/*
> +	 * bit 7 - 4: number of fingers currently touching pad
> +	 * bit 3: valid data check bit
> +	 * bit 2: middle mechanism button state if exists
> +	 * bit 1: right mechanism button state if exists
> +	 * bit 0: left mechanism button state if exists
> +	 */
> +	u8 finger_btn;
> +	struct cyapa_touch touches[CYAPA_MAX_TOUCHES];
> +} __packed;
> +
> +/* The main device structure */
> +struct cyapa {
> +	enum cyapa_state state;
> +
> +	struct i2c_client	*client;
> +	struct input_dev	*input;
> +	char *phys;	/* device physical location */
> +	int irq;
> +	bool irq_wake;  /* irq wake is enabled */
> +
> +	/* power mode settings */
> +	u8 suspend_power_mode;
> +
> +	/* read from query data region. */
> +	char product_id[16];
> +	u8 capability[14];
> +	u8 fw_maj_ver;  /* firmware major version. */
> +	u8 fw_min_ver;  /* firmware minor version. */
> +	u8 hw_maj_ver;  /* hardware major version. */
> +	u8 hw_min_ver;  /* hardware minor version. */
> +	enum cyapa_gen gen;
> +	int max_abs_x;
> +	int max_abs_y;
> +	int physical_size_x;
> +	int physical_size_y;
> +};
> +
> +static const u8 bl_activate[] = { 0x00, 0xff, 0x38, 0x00, 0x01, 0x02, 0x03,
> +		0x04, 0x05, 0x06, 0x07 };
> +static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
> +		0x04, 0x05, 0x06, 0x07 };
> +static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
> +		0x05, 0x06, 0x07 };
> +
> +struct cyapa_cmd_len {
> +	unsigned char cmd;
> +	unsigned char len;
> +};
> +
> +#define CYAPA_ADAPTER_FUNC_NONE   0
> +#define CYAPA_ADAPTER_FUNC_I2C    1
> +#define CYAPA_ADAPTER_FUNC_SMBUS  2
> +#define CYAPA_ADAPTER_FUNC_BOTH   3
> +
> +static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
> +	{CYAPA_OFFSET_SOFT_RESET, 1},
> +	{REG_OFFSET_COMMAND_BASE + 1, 1},
> +	{REG_OFFSET_DATA_BASE, 1},
> +	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
> +	{REG_OFFSET_CONTROL_BASE, 0},
> +	{REG_OFFSET_COMMAND_BASE, 0},
> +	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
> +	{BL_HEAD_OFFSET, 3},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_DATA_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 32},
> +	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
> +	{REG_OFFSET_DATA_BASE, 32}
> +};
> +
> +#define CYAPA_FW_NAME		"cyapa.bin"
> +#define CYAPA_FW_BLOCK_SIZE	64
> +#define CYAPA_FW_HDR_START	0x0780
> +#define CYAPA_FW_HDR_BLOCK_COUNT  2
> +#define CYAPA_FW_HDR_BLOCK_START  (CYAPA_FW_HDR_START / CYAPA_FW_BLOCK_SIZE)
> +#define CYAPA_FW_HDR_SIZE	(CYAPA_FW_HDR_BLOCK_COUNT * \
> +				 CYAPA_FW_BLOCK_SIZE)
> +#define CYAPA_FW_DATA_START	0x0800
> +#define CYAPA_FW_DATA_BLOCK_COUNT  480
> +#define CYAPA_FW_DATA_BLOCK_START  (CYAPA_FW_DATA_START / CYAPA_FW_BLOCK_SIZE)
> +#define CYAPA_FW_DATA_SIZE	(CYAPA_FW_DATA_BLOCK_COUNT * \
> +				 CYAPA_FW_BLOCK_SIZE)
> +#define CYAPA_FW_SIZE		(CYAPA_FW_HDR_SIZE + CYAPA_FW_DATA_SIZE)

There have been a number of similar i2c devices popping up recently.
To, in a driver, present an interface that can convert the trackpad
into a coffee machine is just so entangled.  After all, a kernel
driver is really about conformity, not diversity.  If you must have
it, a generic firmware update scheme via i2c would make more sense.
Or the whole firmware business could simply stay in userspace.

> +#define CYAPA_CMD_LEN		16
> +
> +static void cyapa_detect(struct cyapa *cyapa);

Indicates something needs simplification.

> +
> +#define BYTE_PER_LINE  8
> +void cyapa_dump_data(struct cyapa *cyapa, size_t length, const u8 *data)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int i;
> +	char buf[BYTE_PER_LINE * 3 + 1];
> +	char *s = buf;
> +
> +	for (i = 0; i < length; i++) {
> +		s += sprintf(s, " %02x", data[i]);
> +		if ((i + 1) == length || ((i + 1) % BYTE_PER_LINE) == 0) {
> +			dev_dbg(dev, "%s\n", buf);
> +			s = buf;
> +		}
> +	}
> +}
> +#undef BYTE_PER_LINE

Trailing data never written? Either way look like development
data. Please simplify, correct or remove altogether.

> +
> +/*
> + * cyapa_i2c_reg_read_block - read a block of data from device i2c registers
> + * @cyapa  - private data structure of driver
> + * @reg    - register at which to start reading
> + * @length - length of block to read, in bytes
> + * @values - buffer to store values read from registers
> + *
> + * Returns negative errno, else number of bytes read.
> + *
> + * Note: The trackpad register block is 256 bytes.
> + */
> +static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
> +					u8 *values)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	ssize_t ret;
> +
> +	ret = i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
> +	dev_dbg(dev, "i2c read block reg: 0x%02x len: %zu ret: %zd\n",
> +		reg, len, ret);
> +	if (ret > 0)
> +		cyapa_dump_data(cyapa, ret, values);
> +
> +	return ret;
> +}
> +
> +/*
> + * cyapa_i2c_reg_write_block - write a block of data to device i2c registers
> + * @cyapa  - private data structure of driver
> + * @reg    - register at which to start writing
> + * @length - length of block to write, in bytes
> + * @values - buffer to write to i2c registers
> + *
> + * Returns 0 on success, else negative errno on failure.
> + *
> + * Note: The trackpad register block is 256 bytes.
> + */
> +static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
> +					 size_t len, const u8 *values)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	ssize_t ret;
> +
> +	ret = i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
> +	dev_dbg(dev, "i2c write block reg: 0x%02x len: %zu ret: %zd\n",
> +		reg, len, ret);
> +	cyapa_dump_data(cyapa, len, values);
> +
> +	return ret;
> +}
> +
> +static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 cmd;
> +
> +	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +	ret = i2c_smbus_read_byte_data(cyapa->client, cmd);
> +	dev_dbg(dev, "read byte [0x%02x] = 0x%02x  ret: %d\n",
> +		cmd, ret, ret);
> +
> +	return ret;
> +}
> +
> +static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 cmd;
> +
> +	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +	ret = i2c_smbus_write_byte_data(cyapa->client, cmd, value);
> +	dev_dbg(dev, "write byte [0x%02x] = 0x%02x  ret: %d\n",
> +		cmd, value, ret);
> +
> +	return ret;
> +}
> +

Are you sure you really need all the debug statements above?

> +static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
> +{
> +	u8 cmd;
> +	size_t len;
> +
> +	cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +	len = cyapa_i2c_cmds[cmd_idx].len;
> +	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
> +}
> +
> +/*
> + * Query device for its current operating state.
> + *
> + * Possible states are:
> + *   OPERATION_MODE
> + *   BOOTLOADER_IDLE
> + *   BOOTLOADER_ACTIVE
> + *   BOOTLOADER_BUSY
> + *   NO_DEVICE

This seems redundant, given the enum...

> + *
> + * Returns:
> + *   0 on success, and sets cyapa->state
> + *   < 0 on error, and sets cyapa->state = CYAPA_STATE_NO_DEVICE
> + */
> +static int cyapa_get_state(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 status[BL_STATUS_SIZE];
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +
> +	/*
> +	 * Get trackpad status by reading 3 registers starting from 0.
> +	 * If the device is in the bootloader, this will be BL_HEAD.
> +	 * If the device is in operation mode, this will be the DATA regs.
> +	 *
> +	 */
> +	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
> +				       status);
> +	if (ret != BL_STATUS_SIZE)
> +		return (ret < 0) ? ret : -EAGAIN;
> +
> +	if ((status[REG_OP_STATUS] & OP_STATUS_DEV) == CYAPA_DEV_NORMAL) {
> +		dev_dbg(dev, "device state: operational mode\n");
> +		cyapa->state = CYAPA_STATE_OP;
> +	} else if (status[REG_BL_STATUS] & BL_STATUS_BUSY) {
> +		dev_dbg(dev, "device state: bootloader busy\n");
> +		cyapa->state = CYAPA_STATE_BL_BUSY;
> +	} else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING) {
> +		dev_dbg(dev, "device state: bootloader active\n");
> +		cyapa->state = CYAPA_STATE_BL_ACTIVE;
> +	} else {
> +		dev_dbg(dev, "device state: bootloader idle\n");
> +		cyapa->state = CYAPA_STATE_BL_IDLE;
> +	}
> +
> +	return 0;
> +}
> +/*
> + * Poll device for its status in a loop, waiting up to timeout for a response.
> + *
> + * When the device switches state, it usually takes ~300 ms.
> + * Howere, when running a new firmware image, the device must calibrate its
> + * sensors, which can take as long as 2 seconds.
> + *
> + * Note: The timeout has granularity of the polling rate, which is 300 ms.
> + *
> + * Returns:
> + *   0 when the device eventually responds with a valid non-busy state.
> + *   -ETIMEDOUT if device never responds (too many -EAGAIN)
> + *   < 0    other errors
> + */
> +static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
> +{
> +	int ret;
> +	int tries = timeout / 100;
> +
> +	ret = cyapa_get_state(cyapa);
> +	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
> +		msleep(100);
> +		ret = cyapa_get_state(cyapa);
> +	}
> +	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
> +}
> +
> +/*
> + * Enter bootloader by soft resetting the device.
> + *
> + * If device is already in the bootloader, the function just returns.
> + * Otherwise, reset the device; after reset, device enters bootloader idle
> + * state immediately.
> + *
> + * Also, if device was unregister device from input core.  Device will
> + * re-register after it is detected following resumption of operational mode.
> + *
> + * Returns:
> + *   0 on success
> + *   -EAGAIN  device was reset, but is not now in bootloader idle state
> + *   < 0 if the device never responds within the timeout
> + */
> +static int cyapa_bl_enter(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	if (cyapa->input) {
> +		disable_irq(cyapa->irq);
> +		input_unregister_device(cyapa->input);
> +		cyapa->input = NULL;
> +	}
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return 0;
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +	ret = cyapa_write_byte(cyapa, CYAPA_CMD_SOFT_RESET, 0x01);
> +	if (ret < 0)
> +		return -EIO;
> +
> +	usleep_range(25000, 50000);
> +	ret = cyapa_get_state(cyapa);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_BL_IDLE)
> +		return -EAGAIN;
> +
> +	return 0;
> +}
> +
> +static int cyapa_bl_activate(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_activate),
> +					bl_activate);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Wait for bootloader to activate; takes between 2 and 12 seconds */
> +	msleep(2000);
> +	ret = cyapa_poll_state(cyapa, 10000);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_BL_ACTIVE)
> +		return -EAGAIN;
> +
> +	return 0;
> +}

Hopefully we can simply remove the two functions above.

> +
> +static int cyapa_bl_deactivate(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
> +					bl_deactivate);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* wait for bootloader to switch to idle state; should take < 100ms */
> +	msleep(100);
> +	ret = cyapa_poll_state(cyapa, 500);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_BL_IDLE)
> +		return -EAGAIN;
> +	return 0;
> +}
> +
> +/*
> + * Exit bootloader
> + *
> + * Send bl_exit command, then wait 300 ms to let device transition to
> + * operational mode.  If this is the first time the device's firmware is
> + * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
> + * the device's new state for up to 2 seconds.
> + *
> + * Returns:
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
> + *   0       device is supported and in operational mode
> + */
> +static int cyapa_bl_exit(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * Wait for bootloader to exit, and operation mode to start.
> +	 * Normally, this takes at least 50 ms.
> +	 */
> +	usleep_range(50000, 100000);
> +	/*
> +	 * In addition, when a device boots for the first time after being
> +	 * updated to new firmware, it must first calibrate its sensors, which
> +	 * can take up to an additional 2 seconds.
> +	 */
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EAGAIN;
> +
> +	return 0;
> +}
> +
> +/*
> + * Set device power mode
> + *
> + * Write to the field to configure power state. Power states include :
> + *   Full : Max scans and report rate.
> + *   Idle : Report rate set by user specified time.
> + *   ButtonOnly : No scans for fingers. When the button is triggered,
> + *     a slave interrupt is asserted to notify host to wake up.
> + *   Off : Only awake for i2c commands from host. No function for button
> + *     or touch sensors.
> + *
> + * The power_mode command should conform to the following :
> + *   Full : 0x3f
> + *   Idle : Configurable from 20 to 1000ms. See note below for
> + *     cyapa_sleep_time_to_pwr_cmd and cyapa_pwr_cmd_to_sleep_time
> + *   ButtonOnly : 0x01
> + *   Off : 0x00
> + *
> + * Device power mode can only be set when device is in operational mode.
> + */
> +static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 power;
> +	int tries = SET_POWER_MODE_TRIES;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return 0;
> +
> +	while (true) {
> +		ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
> +		if (ret >= 0 || --tries < 1)
> +			break;
> +		dev_dbg(dev, "set power mode read retry. tries left = %d\n",
> +			tries);
> +		usleep_range(SET_POWER_MODE_DELAY, 2 * SET_POWER_MODE_DELAY);
> +	}
> +	if (ret < 0) {
> +		dev_err(dev, "failed to read power mode %d\n", ret);
> +		return ret;
> +	}
> +
> +	power = ret;
> +	power &= ~PWR_MODE_MASK;
> +	power |= power_mode & PWR_MODE_MASK;
> +	while (true) {
> +		ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
> +		if (!ret || --tries < 1)
> +			break;
> +		dev_dbg(dev, "set power mode write retry. tries left = %d\n",
> +			tries);
> +		usleep_range(SET_POWER_MODE_DELAY, 2 * SET_POWER_MODE_DELAY);
> +	}
> +	if (ret < 0)
> +		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
> +			power_mode, ret);
> +	return ret;
> +}
> +
> +static int cyapa_get_query_data(struct cyapa *cyapa)
> +{
> +	u8 query_data[QUERY_DATA_SIZE];
> +	int ret;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EBUSY;
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
> +	if (ret < 0)
> +		return ret;
> +	if (ret != QUERY_DATA_SIZE)
> +		return -EIO;
> +
> +	memcpy(&cyapa->product_id[0], &query_data[0], 5);
> +	cyapa->product_id[5] = '-';
> +	memcpy(&cyapa->product_id[6], &query_data[5], 6);
> +	cyapa->product_id[12] = '-';
> +	memcpy(&cyapa->product_id[13], &query_data[11], 2);
> +	cyapa->product_id[15] = '\0';
> +
> +	cyapa->fw_maj_ver = query_data[15];
> +	cyapa->fw_min_ver = query_data[16];
> +	cyapa->hw_maj_ver = query_data[17];
> +	cyapa->hw_min_ver = query_data[18];
> +
> +	cyapa->gen = query_data[20] & 0x0f;
> +
> +	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
> +	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
> +
> +	cyapa->physical_size_x =
> +		((query_data[24] & 0xf0) << 4) | query_data[25];
> +	cyapa->physical_size_y =
> +		((query_data[24] & 0x0f) << 8) | query_data[26];
> +
> +	return 0;
> +}
> +
> +/*
> + * Check if device is operational.
> + *
> + * An operational device is responding, has exited bootloader, and has
> + * firmware supported by this driver.
> + *
> + * Returns:
> + *   -EBUSY  no device or in bootloader
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is still in bootloader
> + *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
> + *   -EINVAL device is in operational mode, but not supported by this driver
> + *   0       device is supported
> + */
> +static int cyapa_check_is_operational(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	const char unique_str[] = "CYTRA";
> +	int ret;
> +
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	switch (cyapa->state) {
> +	case CYAPA_STATE_BL_ACTIVE:
> +		ret = cyapa_bl_deactivate(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_BL_IDLE:
> +		ret = cyapa_bl_exit(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_OP:
> +		ret = cyapa_get_query_data(cyapa);
> +		if (ret < 0)
> +			return ret;
> +
> +		/* only support firmware protocol gen3 */
> +		if (cyapa->gen != CYAPA_GEN3) {
> +			dev_err(dev, "unsupported protocol version (%d)",
> +				cyapa->gen);
> +			return -EINVAL;
> +		}
> +
> +		/* only support product ID starting with CYTRA */
> +		if (memcmp(cyapa->product_id, unique_str,
> +			   sizeof(unique_str) - 1)) {

The zero not identical?

> +			dev_err(dev, "unsupported product ID (%s)\n",
> +				cyapa->product_id);
> +			return -EINVAL;
> +		}
> +		return 0;
> +
> +	default:
> +		return -EIO;
> +	}
> +	return 0;
> +}
> +
> +static u16 cyapa_csum(const u8 *buf, size_t count)
> +{
> +	int i;
> +	u16 csum = 0;
> +
> +	for (i = 0; i < count; i++)
> +		csum += buf[i];
> +
> +	return csum;
> +}
> +
> +/*
> + * Write a |len| byte long buffer |buf| to the device, by chopping it up into a
> + * sequence of smaller |CYAPA_CMD_LEN|-length write commands.
> + *
> + * The data bytes for a write command are prepended with the 1-byte offset
> + * of the data relative to the start of |buf|.
> + */
> +static int cyapa_write_buffer(struct cyapa *cyapa, const u8 *buf, size_t len)
> +{
> +	int ret;
> +	size_t i;
> +	unsigned char cmd[CYAPA_CMD_LEN + 1];
> +	size_t cmd_len;
> +
> +	for (i = 0; i < len; i += CYAPA_CMD_LEN) {
> +		const u8 *payload = &buf[i];
> +		cmd_len = (len - i >= CYAPA_CMD_LEN) ? CYAPA_CMD_LEN : len - i;
> +		cmd[0] = i;
> +		memcpy(&cmd[1], payload, cmd_len);
> +
> +		ret = cyapa_i2c_reg_write_block(cyapa, 0, cmd_len + 1, cmd);
> +		if (ret < 0)
> +			return ret;
> +	}
> +	return 0;
> +}
> +
> +/*
> + * A firmware block write command writes 64 bytes of data to a single flash
> + * page in the device.  The 78-byte block write command has the format:
> + *   <0xff> <CMD> <Key> <Start> <Data> <Data-Checksum> <CMD Checksum>
> + *
> + *  <0xff>  - every command starts with 0xff
> + *  <CMD>   - the write command value is 0x39
> + *  <Key>   - write commands include an 8-byte key: { 00 01 02 03 04 05 06 07 }
> + *  <Block> - Memory Block number (address / 64) (16-bit, big-endian)
> + *  <Data>  - 64 bytes of firmware image data
> + *  <Data Checksum> - sum of 64 <Data> bytes, modulo 0xff
> + *  <CMD Checksum> - sum of 77 bytes, from 0xff to <Data Checksum>
> + *
> + * Each write command is split into 5 i2c write transactions of up to 16 bytes.
> + * Each transaction starts with an i2c register offset: (00, 10, 20, 30, 40).
> + */
> +static int cyapa_write_fw_block(struct cyapa *cyapa, u16 block, const u8 *data)
> +{
> +	int ret;
> +	u8 cmd[78];
> +	u8 status[BL_STATUS_SIZE];
> +	int tries = 3;
> +
> +	/* set write command and security key bytes. */
> +	cmd[0] = 0xff;
> +	cmd[1] = 0x39;
> +	cmd[2] = 0x00;
> +	cmd[3] = 0x01;
> +	cmd[4] = 0x02;
> +	cmd[5] = 0x03;
> +	cmd[6] = 0x04;
> +	cmd[7] = 0x05;
> +	cmd[8] = 0x06;
> +	cmd[9] = 0x07;
> +	cmd[10] = block >> 8;
> +	cmd[11] = block;
> +	memcpy(&cmd[12], data, CYAPA_FW_BLOCK_SIZE);
> +	cmd[76] = cyapa_csum(data, CYAPA_FW_BLOCK_SIZE);
> +	cmd[77] = cyapa_csum(cmd, sizeof(cmd) - 1);
> +
> +	ret = cyapa_write_buffer(cyapa, cmd, sizeof(cmd));
> +	if (ret)
> +		return ret;
> +
> +	/* wait for write to finish */
> +	do {
> +		usleep_range(10000, 20000);
> +
> +		/* check block write command result status. */
> +		ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET,
> +					       BL_STATUS_SIZE, status);
> +		if (ret != BL_STATUS_SIZE)
> +			return (ret < 0) ? ret : -EIO;
> +		ret = (status[1] == 0x10 && status[2] == 0x20) ? 0 : -EIO;
> +	} while (--tries && ret);
> +
> +	return ret;
> +}

Hopefully for some other place, then.

> +
> +/*
> + * Verify the integrity of a CYAPA firmware image file.
> + *
> + * The firmware image file is 30848 bytes, composed of 482 64-byte blocks.
> + *
> + * The first 2 blocks are the firmware header.
> + * The next 480 blocks are the firmware image.
> + *
> + * The first two bytes of the header hold the header checksum, computed by
> + * summing the other 126 bytes of the header.
> + * The last two bytes of the header hold the firmware image checksum, computed
> + * by summing the 30720 bytes of the image modulo 0xffff.
> + *
> + * Both checksums are stored little-endian.
> + */
> +static int cyapa_check_fw(struct cyapa *cyapa, const struct firmware *fw)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	u16 csum;
> +	u16 csum_expected;
> +
> +	/* Firmware must match exact 30848 bytes = 482 64-byte blocks. */
> +	if (fw->size != CYAPA_FW_SIZE) {
> +		dev_err(dev, "invalid firmware size = %zu, expected %u.\n",
> +			fw->size, CYAPA_FW_SIZE);
> +		return -EINVAL;
> +	}
> +
> +	/* Verify header block */
> +	csum_expected = (fw->data[0] << 8) | fw->data[1];
> +	csum = cyapa_csum(&fw->data[2], CYAPA_FW_HDR_SIZE - 2);
> +	if (csum != csum_expected) {
> +		dev_err(dev, "invalid firmware header checksum = %04x,", csum);
> +		dev_err(dev, " expected: %04x\n", csum_expected);
> +		return -EINVAL;
> +	}
> +
> +	/* Verify firmware image */
> +	csum_expected = (fw->data[CYAPA_FW_HDR_SIZE - 2] << 8) |
> +			 fw->data[CYAPA_FW_HDR_SIZE - 1];
> +	csum = cyapa_csum(&fw->data[CYAPA_FW_HDR_SIZE], CYAPA_FW_DATA_SIZE);
> +	if (csum != csum_expected) {
> +		dev_err(dev, "invalid firmware checksum = %04x,", csum);
> +		dev_err(dev, " expected: %04x\n", csum_expected);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}

Ditto

> +
> +static int cyapa_firmware(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	const struct firmware *fw;
> +	const char *fw_name = CYAPA_FW_NAME;
> +	int i;
> +
> +	ret = request_firmware(&fw, CYAPA_FW_NAME, dev);
> +	if (ret) {
> +		dev_err(dev, "Could not load firmware from %s, %d\n",
> +			  fw_name, ret);
> +		return ret;
> +	}
> +
> +	ret = cyapa_check_fw(cyapa, fw);
> +	if (ret) {
> +		dev_err(dev, "Invalid CYAPA firmware image: %s\n", fw_name);
> +		goto done;
> +	}
> +
> +	ret = cyapa_bl_enter(cyapa);
> +	if (ret)
> +		goto err_detect;
> +
> +	ret = cyapa_bl_activate(cyapa);
> +	if (ret)
> +		goto err_detect;
> +
> +	/* First write data, starting at byte 128  of fw->data */
> +	for (i = 0; i < CYAPA_FW_DATA_BLOCK_COUNT; i++) {
> +		size_t block = CYAPA_FW_DATA_BLOCK_START + i;
> +		size_t addr = (i + CYAPA_FW_HDR_BLOCK_COUNT) *
> +				CYAPA_FW_BLOCK_SIZE;
> +		const u8 *data = &fw->data[addr];
> +		ret = cyapa_write_fw_block(cyapa, block, data);
> +		if (ret)
> +			goto err_detect;
> +	}
> +
> +	/* Then write checksum */
> +	for (i = 0; i < CYAPA_FW_HDR_BLOCK_COUNT; i++) {
> +		size_t block = CYAPA_FW_HDR_BLOCK_START + i;
> +		size_t addr = i * CYAPA_FW_BLOCK_SIZE;
> +		const u8 *data = &fw->data[addr];
> +		ret = cyapa_write_fw_block(cyapa, block, data);
> +		if (ret)
> +			goto err_detect;
> +	}
> +
> +err_detect:
> +	cyapa_detect(cyapa);
> +
> +done:
> +	release_firmware(fw);
> +	return ret;
> +}

Ditto

> +
> +/*
> + *******************************************************************
> + *	Sysfs Interface.
> + *******************************************************************
> + */
> +static ssize_t cyapa_show_fm_ver(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%d.%d\n", cyapa->fw_maj_ver,
> +			 cyapa->fw_min_ver);
> +}
> +
> +static ssize_t cyapa_show_hw_ver(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%d.%d\n", cyapa->hw_maj_ver,
> +			 cyapa->hw_min_ver);
> +}
> +
> +static ssize_t cyapa_show_product_id(struct device *dev,
> +				     struct device_attribute *attr, char *buf)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%s\n", cyapa->product_id);
> +}
> +
> +static ssize_t cyapa_show_protocol_version(struct device *dev,
> +					   struct device_attribute *attr,
> +					   char *buf)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	return scnprintf(buf, PAGE_SIZE, "%d\n", cyapa->gen);
> +}
> +
> +static ssize_t cyapa_update_fw_store(struct device *dev,
> +				     struct device_attribute *attr,
> +				     const char *buf, size_t count)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = cyapa_firmware(cyapa);
> +	if (ret)
> +		dev_err(dev, "firmware update failed, %d\n", ret);
> +	else
> +		dev_dbg(dev, "firmware update succeeded\n");
> +
> +	return ret ? ret : count;
> +}

Rather not, please.

> +
> +/*
> + * cyapa_sleep_time_to_pwr_cmd and cyapa_pwr_cmd_to_sleep_time
> + *
> + * These are helper functions that convert to and from integer idle
> + * times and register settings to write to the PowerMode register.
> + * The trackpad supports between 20ms to 1000ms scan intervals.
> + * The time will be increased in increments of 10ms from 20ms to 100ms.
> + * From 100ms to 1000ms, time will be increased in increments of 20ms.
> + *
> + * When Idle_Time < 100, the format to convert Idle_Time to Idle_Command is:
> + *   Idle_Command = Idle Time / 10;
> + * When Idle_Time >= 100, the format to convert Idle_Time to Idle_Command is:
> + *   Idle_Command = Idle Time / 20 + 5;
> + */
> +static u8 cyapa_sleep_time_to_pwr_cmd(u16 sleep_time)
> +{
> +	if (sleep_time < 20)
> +		sleep_time = 20;     /* minimal sleep time. */
> +	else if (sleep_time > 1000)
> +		sleep_time = 1000;   /* maximal sleep time. */
> +
> +	if (sleep_time < 100)
> +		return ((sleep_time / 10) << 2) & PWR_MODE_MASK;
> +	else
> +		return ((sleep_time / 20 + 5) << 2) & PWR_MODE_MASK;
> +}
> +
> +static u16 cyapa_pwr_cmd_to_sleep_time(u8 pwr_mode)
> +{
> +	u8 encoded_time = pwr_mode >> 2;
> +	return (encoded_time < 10) ? encoded_time * 10
> +				   : (encoded_time - 5) * 20;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static ssize_t cyapa_show_suspend_scanrate(struct device *dev,
> +					   struct device_attribute *attr,
> +					   char *buf)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	int len;
> +	u8 pwr_cmd = cyapa->suspend_power_mode;
> +
> +	if (pwr_cmd == PWR_MODE_BTN_ONLY)
> +		len = scnprintf(buf, PAGE_SIZE, "%s\n", BTN_ONLY_MODE_NAME);
> +	else
> +		len = scnprintf(buf, PAGE_SIZE, "%u\n",
> +				cyapa_pwr_cmd_to_sleep_time(pwr_cmd));
> +	return len;
> +}
> +
> +static ssize_t cyapa_update_suspend_scanrate(struct device *dev,
> +					     struct device_attribute *attr,
> +					     const char *buf, size_t count)
> +{
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +	u8 pwr_cmd;
> +	u16 sleep_time;
> +
> +	if (buf == NULL || count == 0)
> +		goto invalidparam;
> +
> +	if (sysfs_streq(buf, BTN_ONLY_MODE_NAME))
> +		pwr_cmd = PWR_MODE_BTN_ONLY;
> +	else if (!kstrtou16(buf, 10, &sleep_time))
> +		pwr_cmd = cyapa_sleep_time_to_pwr_cmd(sleep_time);
> +	else
> +		goto invalidparam;
> +
> +	cyapa->suspend_power_mode = pwr_cmd;
> +	return count;
> +
> +invalidparam:
> +	dev_err(dev, "invalid suspend scanrate ms parameters\n");
> +	return -EINVAL;
> +}
> +
> +static DEVICE_ATTR(suspend_scanrate_ms, S_IRUGO|S_IWUSR,
> +		   cyapa_show_suspend_scanrate,
> +		   cyapa_update_suspend_scanrate);

Why?

> +
> +static struct attribute *cyapa_power_wakeup_entries[] = {
> +	&dev_attr_suspend_scanrate_ms.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group cyapa_power_wakeup_group = {
> +	.name = power_group_name,
> +	.attrs = cyapa_power_wakeup_entries,
> +};
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static DEVICE_ATTR(firmware_version, S_IRUGO, cyapa_show_fm_ver, NULL);
> +static DEVICE_ATTR(hardware_version, S_IRUGO, cyapa_show_hw_ver, NULL);
> +static DEVICE_ATTR(product_id, S_IRUGO, cyapa_show_product_id, NULL);
> +static DEVICE_ATTR(protocol_version, S_IRUGO, cyapa_show_protocol_version,
> +		   NULL);
> +static DEVICE_ATTR(update_fw, S_IWUSR, NULL, cyapa_update_fw_store);
> +
> +static struct attribute *cyapa_sysfs_entries[] = {
> +	&dev_attr_firmware_version.attr,
> +	&dev_attr_hardware_version.attr,
> +	&dev_attr_product_id.attr,
> +	&dev_attr_protocol_version.attr,
> +	&dev_attr_update_fw.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group cyapa_sysfs_group = {
> +	.attrs = cyapa_sysfs_entries,
> +};

At this point, only some 10% of the file is about _this_ driver and
its functionality. The rest is about some _future_ or possible
functionality. It should really be the other way around.

> +
> +/*
> + **************************************************************
> + * Cypress APA trackpad with I2C interface input device driver.
> + **************************************************************
> + */
> +
> +static irqreturn_t cyapa_irq(int irq, void *dev_id)
> +{
> +	struct cyapa *cyapa = dev_id;
> +	struct device *dev = &cyapa->client->dev;
> +	struct input_dev *input = cyapa->input;
> +	struct cyapa_reg_data data;
> +	int i;
> +	int ret;
> +	int num_fingers;
> +	unsigned int mask;
> +
> +	/*
> +	 * Don't read input if input device has not been configured.
> +	 * This check check solves a race during probe() between irq_request()
> +	 * and irq_disable(), since there is no way to request an irq that is
> +	 * initially disabled.
> +	 */
> +	if (!input)
> +		return IRQ_HANDLED;

This is just confused. Why not configure the input device before
starting the interrupt?

> +
> +	if (device_may_wakeup(dev))
> +		pm_wakeup_event(dev, 0);
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
> +	if (ret != sizeof(data))
> +		return IRQ_HANDLED;
> +
> +	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
> +	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
> +	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
> +		return IRQ_HANDLED;
> +	}
> +
> +	mask = 0;
> +	num_fingers = (data.finger_btn >> 4) & 0x0f;
> +	for (i = 0; i < num_fingers; i++) {
> +		const struct cyapa_touch *touch = &data.touches[i];
> +		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
> +		int slot = touch->id - 1;
> +
> +		mask |= (1 << slot);
> +		input_mt_slot(input, slot);
> +		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
> +		input_report_abs(input, ABS_MT_POSITION_X,
> +				 ((touch->xy & 0xf0) << 4) | touch->x);
> +		input_report_abs(input, ABS_MT_POSITION_Y,
> +				 ((touch->xy & 0x0f) << 8) | touch->y);
> +		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
> +	}
> +
> +	/* Invalidate all unreported slots */
> +	for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
> +		if (mask & (1 << i))
> +			continue;
> +		input_mt_slot(input, i);
> +		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
> +	}
> +
> +	input_mt_report_pointer_emulation(input, true);
> +	input_report_key(input, BTN_LEFT, data.finger_btn & OP_DATA_BTN_MASK);
> +	input_sync(input);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int cyapa_create_input_dev(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	struct input_dev *input;
> +
> +	dev_info(dev,
> +		 "Cypress APA Trackpad Information:\n" \
> +		 "    Product ID:  %s\n" \
> +		 "    Protocol Generation:  %d\n" \
> +		 "    Firmware Version:  %d.%d\n" \
> +		 "    Hardware Version:  %d.%d\n" \
> +		 "    Max ABS X,Y:   %d,%d\n" \
> +		 "    Physical Size X,Y:   %d,%d\n",
> +		 cyapa->product_id,
> +		 cyapa->gen,
> +		 cyapa->fw_maj_ver, cyapa->fw_min_ver,
> +		 cyapa->hw_maj_ver, cyapa->hw_min_ver,
> +		 cyapa->max_abs_x, cyapa->max_abs_y,
> +		 cyapa->physical_size_x, cyapa->physical_size_y);

Way too chatty for the main logs.

> +
> +	input = cyapa->input = input_allocate_device();
> +	if (!input) {
> +		dev_err(dev, "allocate memory for input device failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = CYAPA_NAME;
> +	input->phys = cyapa->phys;
> +	input->id.bustype = BUS_I2C;
> +	input->id.version = 1;
> +	input->id.product = 0;  /* means any product in eventcomm. */
> +	input->dev.parent = &cyapa->client->dev;
> +
> +	input_set_drvdata(input, cyapa);
> +
> +	__set_bit(EV_ABS, input->evbit);
> +
> +	/*
> +	 * set and report not-MT axes to support synaptics X Driver.
> +	 * When multi-fingers on trackpad, only the first finger touch
> +	 * will be reported as X/Y axes values.
> +	 */
> +	input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
> +	input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
> +	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
> +
> +	/* finger position */
> +	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
> +	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
> +	if (ret < 0) {
> +		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +
> +	if (cyapa->physical_size_x && cyapa->physical_size_y) {
> +		input_abs_set_res(input, ABS_X,
> +			cyapa->max_abs_x / cyapa->physical_size_x);
> +		input_abs_set_res(input, ABS_Y,
> +			cyapa->max_abs_y / cyapa->physical_size_y);
> +		input_abs_set_res(input, ABS_MT_POSITION_X,
> +			cyapa->max_abs_x / cyapa->physical_size_x);
> +		input_abs_set_res(input, ABS_MT_POSITION_Y,
> +			cyapa->max_abs_y / cyapa->physical_size_y);
> +	}
> +
> +	__set_bit(EV_KEY, input->evbit);
> +	__set_bit(BTN_TOUCH, input->keybit);
> +	__set_bit(BTN_TOOL_FINGER, input->keybit);
> +	__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
> +	__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
> +	__set_bit(BTN_TOOL_QUADTAP, input->keybit);
> +	__set_bit(BTN_TOOL_QUINTTAP, input->keybit);
> +
> +	__set_bit(BTN_LEFT, input->keybit);
> +
> +	__set_bit(INPUT_PROP_POINTER, input->propbit);
> +	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
> +
> +	/* Register the device in input subsystem */
> +	ret = input_register_device(input);
> +	if (ret) {
> +		dev_err(dev, "input device register failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +
> +	enable_irq(cyapa->irq);
> +	return 0;
> +
> +err_free_device:
> +	input_free_device(input);
> +	cyapa->input = NULL;
> +	return ret;
> +}
> +
> +static void cyapa_detect(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +
> +	ret = cyapa_check_is_operational(cyapa);
> +	if (ret == -ETIMEDOUT) {
> +		dev_err(dev, "no device detected, %d\n", ret);
> +		return;
> +	} else if (ret) {
> +		dev_err(dev, "device detected, but not operational, %d\n", ret);
> +		return;
> +	}
> +
> +	if (!cyapa->input) {
> +		ret = cyapa_create_input_dev(cyapa);
> +		if (ret)
> +			dev_err(dev, "create input_dev instance failed, %d\n",
> +				ret);
> +
> +		/*
> +		 * On some systems, a system crash / warm boot does not reset
> +		 * the device's current power mode to FULL_ACTIVE.
> +		 * If such an event happens during suspend, after the device
> +		 * has been put in a low power mode, the device will still be
> +		 * in low power mode on a subsequent boot, since there was
> +		 * never a matching resume().
> +		 * Handle this by always forcing full power here, when a
> +		 * device is first detected to be in operational mode.
> +		 */
> +		ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +		if (ret)
> +			dev_warn(dev, "set active power failed, %d\n", ret);
> +	}
> +}

This function does what that differs from probe()?

> +
> +static int __devinit cyapa_probe(struct i2c_client *client,
> +				 const struct i2c_device_id *dev_id)
> +{
> +	int ret;
> +	struct cyapa *cyapa;
> +	struct device *dev = &client->dev;
> +
> +	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
> +	if (!cyapa) {
> +		dev_err(dev, "allocate memory for cyapa failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	cyapa->gen = CYAPA_GEN3;
> +	cyapa->client = client;
> +	i2c_set_clientdata(client, cyapa);
> +	cyapa->phys = kasprintf(GFP_KERNEL, "i2c-%d-%04x/input0",
> +				client->adapter->nr, client->addr);
> +	if (!cyapa->phys) {
> +		ret = -ENOMEM;
> +		goto err_mem_free;
> +	}
> +
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +	cyapa->suspend_power_mode = PWR_MODE_IDLE;
> +
> +	/*
> +	 * Note: There is no way to request an irq that is initially disabled.
> +	 * Thus, there is a little race here, which is resolved in cyapa_irq()
> +	 * by checking that cyapa->input has been allocated, which happens
> +	 * in cyapa_detect(), before creating input events.
> +	 */
> +	cyapa->irq = client->irq;
> +	ret = request_threaded_irq(cyapa->irq,
> +				   NULL,
> +				   cyapa_irq,
> +				   IRQF_TRIGGER_FALLING,
> +				   "cyapa",
> +				   cyapa);

Excess linebreaks.

> +	if (ret) {
> +		dev_err(dev, "IRQ request failed: %d\n, ", ret);
> +		goto err_mem_free;
> +	}
> +	disable_irq(cyapa->irq);
> +
> +	if (sysfs_create_group(&client->dev.kobj, &cyapa_sysfs_group))
> +		dev_warn(dev, "error creating sysfs entries.\n");
> +
> +#ifdef CONFIG_PM_SLEEP
> +	if (device_can_wakeup(dev) &&
> +	    sysfs_merge_group(&client->dev.kobj, &cyapa_power_wakeup_group))
> +		dev_warn(dev, "error creating wakeup power entries.\n");
> +#endif /* CONFIG_PM_SLEEP */
> +
> +	cyapa_detect(cyapa);
> +
> +	return 0;
> +
> +err_mem_free:
> +	kfree(cyapa->phys);
> +	kfree(cyapa);
> +
> +	return ret;
> +}
> +
> +static int __devexit cyapa_remove(struct i2c_client *client)
> +{
> +	struct cyapa *cyapa = i2c_get_clientdata(client);
> +
> +	sysfs_remove_group(&client->dev.kobj, &cyapa_sysfs_group);
> +
> +	free_irq(cyapa->irq, cyapa);
> +
> +	if (cyapa->input)
> +		input_unregister_device(cyapa->input);
> +
> +	kfree(cyapa->phys);
> +	kfree(cyapa);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cyapa_suspend(struct device *dev)
> +{
> +	int ret;
> +	u8 power_mode;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	/* set trackpad device to idle mode if wakeup is allowed
> +	 * otherwise turn off. */
> +	power_mode = device_may_wakeup(dev) ? cyapa->suspend_power_mode
> +					    : PWR_MODE_OFF;
> +	ret = cyapa_set_power_mode(cyapa, power_mode);
> +	if (ret < 0)
> +		dev_err(dev, "set power mode failed, %d\n", ret);
> +
> +	if (device_may_wakeup(dev))
> +		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
> +	disable_irq(cyapa->irq);
> +
> +	return 0;
> +}
> +
> +static int cyapa_resume(struct device *dev)
> +{
> +	int ret;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	enable_irq(cyapa->irq);
> +	if (device_may_wakeup(dev) && cyapa->irq_wake)
> +		disable_irq_wake(cyapa->irq);
> +
> +	cyapa_detect(cyapa);
> +
> +	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +	if (ret)
> +		dev_warn(dev, "resume active power failed, %d\n", ret);
> +
> +	return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
> +
> +static const struct i2c_device_id cyapa_id_table[] = {
> +	{ "cyapa", 0 },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
> +
> +static struct i2c_driver cyapa_driver = {
> +	.driver = {
> +		.name = "cyapa",
> +		.owner = THIS_MODULE,
> +		.pm = &cyapa_pm_ops,
> +	},
> +
> +	.probe = cyapa_probe,
> +	.remove = __devexit_p(cyapa_remove),
> +	.id_table = cyapa_id_table,
> +};
> +
> +module_i2c_driver(cyapa_driver);
> +
> +MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
> +MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
> +MODULE_LICENSE("GPL");
> -- 
> 1.7.7.3
> 

All in all, it would be great to see this driver shrink to
approximately one fourth of its present size.

Thanks,
Henrik

^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v2 0/1] Input: add driver for Cypress APA I2C Trackpad
  2012-07-10 22:29 [PATCH] Input: add driver for Cypress APA I2C Trackpad Benson Leung
  2012-07-16 11:05 ` Henrik Rydberg
@ 2012-12-06  0:48 ` Benson Leung
  2012-12-06  0:48   ` [PATCH v2 1/1] " Benson Leung
  2012-12-07 23:24   ` [PATCH v3 0/1] " Benson Leung
  1 sibling, 2 replies; 14+ messages in thread
From: Benson Leung @ 2012-12-06  0:48 UTC (permalink / raw)
  To: dmitry.torokhov, rydberg, linux-input, linux-kernel
  Cc: bleung, djkurtz, olofj, dudl

Thanks for the patience on this driver. I have stripped out firmware update,
the sysfs properties around firmware version, hardware version, update_fw,
and power state.

I have incorporated rydberg's suggestions for cleanup.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06  0:48 ` [PATCH v2 0/1] " Benson Leung
@ 2012-12-06  0:48   ` Benson Leung
  2012-12-06  7:48     ` Dmitry Torokhov
  2012-12-06 14:59     ` Henrik Rydberg
  2012-12-07 23:24   ` [PATCH v3 0/1] " Benson Leung
  1 sibling, 2 replies; 14+ messages in thread
From: Benson Leung @ 2012-12-06  0:48 UTC (permalink / raw)
  To: dmitry.torokhov, rydberg, linux-input, linux-kernel
  Cc: bleung, djkurtz, olofj, dudl

This patch introduces a driver for Cypress All Points Addressable
I2C Trackpad, including the ones in 2012 Samsung Chromebooks.

This device is compatible with MT protocol type B, providing identifiable
contacts.

Signed-off-by: Dudley Du <dudl@cypress.com>
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Benson Leung <bleung@chromium.org>
---
 Version history :
v2 : * Removed firmware update.
     * Removed sysfs properties related to firmware update and power mode.
     * Folded cyapa_detect into cyapa_probe.
     * Added support for middle and right mechanical buttons, if they exist.
     * Rearranged disable_irq/enable_irq in suspend and resume to prevent
         a power mode change from colliding with a read of tracking data.
     * Made cyapa_get_state more reliable.
     * Use IRQF_ONESHOT for threaded irq
     * Simplified cyapa_set_power_mode.
     * Removed extra kernel-doc style comments
     * Removed dev_dbg messages.
     * Cleaned up unused includes.
     * Cleaned up unused #defines
v1 : Initial
---
 drivers/input/mouse/Kconfig  |   12 +
 drivers/input/mouse/Makefile |    1 +
 drivers/input/mouse/cyapa.c  |  838 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 851 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/mouse/cyapa.c

diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
index cd6268c..23db30a 100644
--- a/drivers/input/mouse/Kconfig
+++ b/drivers/input/mouse/Kconfig
@@ -193,6 +193,18 @@ config MOUSE_BCM5974
 	  To compile this driver as a module, choose M here: the
 	  module will be called bcm5974.
 
+config MOUSE_CYAPA
+	tristate "Cypress APA I2C Trackpad support"
+	depends on I2C
+	help
+	  This driver adds support for Cypress All Points Addressable (APA)
+	  I2C Trackpads, including the ones used in 2012 Samsung Chromebooks.
+
+	  Say Y here if you have a Cypress APA I2C Trackpad.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called cyapa.
+
 config MOUSE_INPORT
 	tristate "InPort/MS/ATIXL busmouse"
 	depends on ISA
diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
index 46ba755..10b4773 100644
--- a/drivers/input/mouse/Makefile
+++ b/drivers/input/mouse/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
 obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
 obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
 obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
+obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
 obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
 obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
 obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
new file mode 100644
index 0000000..08cf1ce
--- /dev/null
+++ b/drivers/input/mouse/cyapa.c
@@ -0,0 +1,838 @@
+/*
+ * Cypress APA trackpad with I2C interface
+ *
+ * Author: Dudley Du <dudl@cypress.com>
+ * Further cleanup and restructuring by:
+ *   Daniel Kurtz <djkurtz@chromium.org>
+ *   Benson Leung <bleung@chromium.org>
+ *
+ * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Google, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+/* APA trackpad firmware generation */
+#define CYAPA_GEN3   0x03   /* support MT-protocol B with tracking ID. */
+
+#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
+
+/* commands for read/write registers of Cypress trackpad */
+#define CYAPA_CMD_SOFT_RESET       0x00
+#define CYAPA_CMD_POWER_MODE       0x01
+#define CYAPA_CMD_DEV_STATUS       0x02
+#define CYAPA_CMD_GROUP_DATA       0x03
+#define CYAPA_CMD_GROUP_CMD        0x04
+#define CYAPA_CMD_GROUP_QUERY      0x05
+#define CYAPA_CMD_BL_STATUS        0x06
+#define CYAPA_CMD_BL_HEAD          0x07
+#define CYAPA_CMD_BL_CMD           0x08
+#define CYAPA_CMD_BL_DATA          0x09
+#define CYAPA_CMD_BL_ALL           0x0a
+#define CYAPA_CMD_BLK_PRODUCT_ID   0x0b
+#define CYAPA_CMD_BLK_HEAD         0x0c
+
+/* report data start reg offset address. */
+#define DATA_REG_START_OFFSET  0x0000
+
+#define BL_HEAD_OFFSET 0x00
+#define BL_DATA_OFFSET 0x10
+
+/*
+ * Operational Device Status Register
+ *
+ * bit 7: Valid interrupt source
+ * bit 6 - 4: Reserved
+ * bit 3 - 2: Power status
+ * bit 1 - 0: Device status
+ */
+#define REG_OP_STATUS     0x00
+#define OP_STATUS_SRC     0x80
+#define OP_STATUS_POWER   0x0c
+#define OP_STATUS_DEV     0x03
+#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
+
+/*
+ * Operational Finger Count/Button Flags Register
+ *
+ * bit 7 - 4: Number of touched finger
+ * bit 3: Valid data
+ * bit 2: Middle Physical Button
+ * bit 1: Right Physical Button
+ * bit 0: Left physical Button
+ */
+#define REG_OP_DATA1       0x01
+#define OP_DATA_VALID      0x08
+#define OP_DATA_MIDDLE_BTN 0x04
+#define OP_DATA_RIGHT_BTN  0x02
+#define OP_DATA_LEFT_BTN   0x01
+#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
+			  OP_DATA_LEFT_BTN)
+
+/*
+ * Bootloader Status Register
+ *
+ * bit 7: Busy
+ * bit 6 - 5: Reserved
+ * bit 4: Bootloader running
+ * bit 3 - 1: Reserved
+ * bit 0: Checksum valid
+ */
+#define REG_BL_STATUS        0x01
+#define BL_STATUS_BUSY       0x80
+#define BL_STATUS_RUNNING    0x10
+#define BL_STATUS_DATA_VALID 0x08
+#define BL_STATUS_CSUM_VALID 0x01
+
+/*
+ * Bootloader Error Register
+ *
+ * bit 7: Invalid
+ * bit 6: Invalid security key
+ * bit 5: Bootloading
+ * bit 4: Command checksum
+ * bit 3: Flash protection error
+ * bit 2: Flash checksum error
+ * bit 1 - 0: Reserved
+ */
+#define REG_BL_ERROR         0x02
+#define BL_ERROR_INVALID     0x80
+#define BL_ERROR_INVALID_KEY 0x40
+#define BL_ERROR_BOOTLOADING 0x20
+#define BL_ERROR_CMD_CSUM    0x10
+#define BL_ERROR_FLASH_PROT  0x08
+#define BL_ERROR_FLASH_CSUM  0x04
+
+#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
+#define BLK_HEAD_BYTES 32
+
+#define PRODUCT_ID_SIZE  16
+#define QUERY_DATA_SIZE  27
+#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
+
+#define REG_OFFSET_DATA_BASE     0x0000
+#define REG_OFFSET_COMMAND_BASE  0x0028
+#define REG_OFFSET_QUERY_BASE    0x002a
+
+#define CAPABILITY_LEFT_BTN_MASK	(0x01 << 3)
+#define CAPABILITY_RIGHT_BTN_MASK	(0x01 << 4)
+#define CAPABILITY_MIDDLE_BTN_MASK	(0x01 << 5)
+#define CAPABILITY_BTN_MASK  (CAPABILITY_LEFT_BTN_MASK | \
+			      CAPABILITY_RIGHT_BTN_MASK | \
+			      CAPABILITY_MIDDLE_BTN_MASK)
+
+#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
+
+#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
+
+#define PWR_MODE_MASK   0xfc
+#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
+#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
+#define PWR_MODE_OFF         (0x00 << 2)
+
+#define PWR_STATUS_MASK      0x0c
+#define PWR_STATUS_ACTIVE    (0x03 << 2)
+#define PWR_STATUS_IDLE      (0x02 << 2)
+#define PWR_STATUS_OFF       (0x00 << 2)
+
+/*
+ * CYAPA trackpad device states.
+ * Used in register 0x00, bit1-0, DeviceStatus field.
+ * Other values indicate device is in an abnormal state and must be reset.
+ */
+#define CYAPA_DEV_NORMAL  0x03
+#define CYAPA_DEV_BUSY    0x01
+
+enum cyapa_state {
+	CYAPA_STATE_OP,
+	CYAPA_STATE_BL_IDLE,
+	CYAPA_STATE_BL_ACTIVE,
+	CYAPA_STATE_BL_BUSY,
+	CYAPA_STATE_NO_DEVICE,
+};
+
+
+struct cyapa_touch {
+	/*
+	 * high bits or x/y position value
+	 * bit 7 - 4: high 4 bits of x position value
+	 * bit 3 - 0: high 4 bits of y position value
+	 */
+	u8 xy_hi;
+	u8 x_lo;  /* low 8 bits of x position value. */
+	u8 y_lo;  /* low 8 bits of y position value. */
+	u8 pressure;
+	/* id range is 1 - 15.  It is incremented with every new touch. */
+	u8 id;
+} __packed;
+
+/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
+#define CYAPA_MAX_MT_SLOTS  15
+
+struct cyapa_reg_data {
+	/*
+	 * bit 0 - 1: device status
+	 * bit 3 - 2: power mode
+	 * bit 6 - 4: reserved
+	 * bit 7: interrupt valid bit
+	 */
+	u8 device_status;
+	/*
+	 * bit 7 - 4: number of fingers currently touching pad
+	 * bit 3: valid data check bit
+	 * bit 2: middle mechanism button state if exists
+	 * bit 1: right mechanism button state if exists
+	 * bit 0: left mechanism button state if exists
+	 */
+	u8 finger_btn;
+	/* CYAPA reports up to 5 touches per packet. */
+	struct cyapa_touch touches[5];
+} __packed;
+
+/* The main device structure */
+struct cyapa {
+	enum cyapa_state state;
+
+	struct i2c_client *client;
+	struct input_dev *input;
+	char *phys;	/* device physical location */
+	int irq;
+	bool irq_wake;  /* irq wake is enabled */
+
+	/* read from query data region. */
+	char product_id[16];
+	u8 btn_capability;
+	u8 gen;
+	int max_abs_x;
+	int max_abs_y;
+	int physical_size_x;
+	int physical_size_y;
+};
+
+static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
+		0x04, 0x05, 0x06, 0x07 };
+static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
+		0x05, 0x06, 0x07 };
+
+struct cyapa_cmd_len {
+	u8 cmd;
+	u8 len;
+};
+
+static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
+	{CYAPA_OFFSET_SOFT_RESET, 1},
+	{REG_OFFSET_COMMAND_BASE + 1, 1},
+	{REG_OFFSET_DATA_BASE, 1},
+	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
+	{REG_OFFSET_COMMAND_BASE, 0},
+	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
+	{BL_HEAD_OFFSET, 3},
+	{BL_HEAD_OFFSET, 16},
+	{BL_HEAD_OFFSET, 16},
+	{BL_DATA_OFFSET, 16},
+	{BL_HEAD_OFFSET, 32},
+	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
+	{REG_OFFSET_DATA_BASE, 32}
+};
+
+static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
+					u8 *values)
+{
+	return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
+}
+
+static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
+					 size_t len, const u8 *values)
+{
+	return i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
+}
+
+static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+
+	return i2c_smbus_read_byte_data(cyapa->client, cmd);
+}
+
+static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+
+	return i2c_smbus_write_byte_data(cyapa->client, cmd, value);
+}
+
+static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+	size_t len = cyapa_i2c_cmds[cmd_idx].len;
+
+	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
+}
+
+/*
+ * Query device for its current operating state.
+ *
+ */
+static int cyapa_get_state(struct cyapa *cyapa)
+{
+	int ret;
+	u8 status[BL_STATUS_SIZE];
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+
+	/*
+	 * Get trackpad status by reading 3 registers starting from 0.
+	 * If the device is in the bootloader, this will be BL_HEAD.
+	 * If the device is in operation mode, this will be the DATA regs.
+	 *
+	 */
+	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
+				       status);
+	if (ret != BL_STATUS_SIZE)
+		goto error;
+
+	if ((status[REG_OP_STATUS] & OP_STATUS_SRC) == OP_STATUS_SRC) {
+		switch (status[REG_OP_STATUS] & OP_STATUS_DEV) {
+		case CYAPA_DEV_NORMAL:
+		case CYAPA_DEV_BUSY:
+			cyapa->state = CYAPA_STATE_OP;
+			break;
+		default:
+			ret = -EAGAIN;
+			goto error;
+		}
+	} else {
+		if (status[REG_BL_STATUS] & BL_STATUS_BUSY)
+			cyapa->state = CYAPA_STATE_BL_BUSY;
+		else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING)
+			cyapa->state = CYAPA_STATE_BL_ACTIVE;
+		else
+			cyapa->state = CYAPA_STATE_BL_IDLE;
+	}
+
+	return 0;
+error:
+	return (ret < 0) ? ret : -EAGAIN;
+}
+
+/*
+ * Poll device for its status in a loop, waiting up to timeout for a response.
+ *
+ * When the device switches state, it usually takes ~300 ms.
+ * However, when running a new firmware image, the device must calibrate its
+ * sensors, which can take as long as 2 seconds.
+ *
+ * Note: The timeout has granularity of the polling rate, which is 100 ms.
+ *
+ * Returns:
+ *   0 when the device eventually responds with a valid non-busy state.
+ *   -ETIMEDOUT if device never responds (too many -EAGAIN)
+ *   < 0    other errors
+ */
+static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
+{
+	int ret;
+	int tries = timeout / 100;
+
+	ret = cyapa_get_state(cyapa);
+	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
+		msleep(100);
+		ret = cyapa_get_state(cyapa);
+	}
+	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
+}
+
+static int cyapa_bl_deactivate(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
+					bl_deactivate);
+	if (ret < 0)
+		return ret;
+
+	/* wait for bootloader to switch to idle state; should take < 100ms */
+	msleep(100);
+	ret = cyapa_poll_state(cyapa, 500);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_BL_IDLE)
+		return -EAGAIN;
+	return 0;
+}
+
+/*
+ * Exit bootloader
+ *
+ * Send bl_exit command, then wait 50 - 100 ms to let device transition to
+ * operational mode.  If this is the first time the device's firmware is
+ * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
+ * the device's new state for up to 2 seconds.
+ *
+ * Returns:
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
+ *   0       device is supported and in operational mode
+ */
+static int cyapa_bl_exit(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Wait for bootloader to exit, and operation mode to start.
+	 * Normally, this takes at least 50 ms.
+	 */
+	usleep_range(50000, 100000);
+	/*
+	 * In addition, when a device boots for the first time after being
+	 * updated to new firmware, it must first calibrate its sensors, which
+	 * can take up to an additional 2 seconds.
+	 */
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EAGAIN;
+
+	return 0;
+}
+
+/*
+ * Set device power mode
+ *
+ */
+static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 power;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return 0;
+
+	ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
+	if (ret < 0)
+		return ret;
+
+	power = ret & ~PWR_MODE_MASK;
+	power |= power_mode & PWR_MODE_MASK;
+	ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
+	if (ret < 0)
+		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
+			power_mode, ret);
+	return ret;
+}
+
+static int cyapa_get_query_data(struct cyapa *cyapa)
+{
+	u8 query_data[QUERY_DATA_SIZE];
+	int ret;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EBUSY;
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
+	if (ret < 0)
+		return ret;
+	if (ret != QUERY_DATA_SIZE)
+		return -EIO;
+
+	memcpy(&cyapa->product_id[0], &query_data[0], 5);
+	cyapa->product_id[5] = '-';
+	memcpy(&cyapa->product_id[6], &query_data[5], 6);
+	cyapa->product_id[12] = '-';
+	memcpy(&cyapa->product_id[13], &query_data[11], 2);
+	cyapa->product_id[15] = '\0';
+
+	cyapa->btn_capability = query_data[19] & CAPABILITY_BTN_MASK;
+
+	cyapa->gen = query_data[20] & 0x0f;
+
+	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
+	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
+
+	cyapa->physical_size_x =
+		((query_data[24] & 0xf0) << 4) | query_data[25];
+	cyapa->physical_size_y =
+		((query_data[24] & 0x0f) << 8) | query_data[26];
+
+	return 0;
+}
+
+/*
+ * Check if device is operational.
+ *
+ * An operational device is responding, has exited bootloader, and has
+ * firmware supported by this driver.
+ *
+ * Returns:
+ *   -EBUSY  no device or in bootloader
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is still in bootloader
+ *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
+ *   -EINVAL device is in operational mode, but not supported by this driver
+ *   0       device is supported
+ */
+static int cyapa_check_is_operational(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	static const char unique_str[] = "CYTRA";
+	int ret;
+
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	switch (cyapa->state) {
+	case CYAPA_STATE_BL_ACTIVE:
+		ret = cyapa_bl_deactivate(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_BL_IDLE:
+		ret = cyapa_bl_exit(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_OP:
+		ret = cyapa_get_query_data(cyapa);
+		if (ret < 0)
+			return ret;
+
+		/* only support firmware protocol gen3 */
+		if (cyapa->gen != CYAPA_GEN3) {
+			dev_err(dev, "unsupported protocol version (%d)",
+				cyapa->gen);
+			return -EINVAL;
+		}
+
+		/* only support product ID starting with CYTRA */
+		if (memcmp(cyapa->product_id, unique_str,
+			   sizeof(unique_str) - 1) != 0) {
+			dev_err(dev, "unsupported product ID (%s)\n",
+				cyapa->product_id);
+			return -EINVAL;
+		}
+		return 0;
+
+	default:
+		return -EIO;
+	}
+	return 0;
+}
+
+static irqreturn_t cyapa_irq(int irq, void *dev_id)
+{
+	struct cyapa *cyapa = dev_id;
+	struct device *dev = &cyapa->client->dev;
+	struct input_dev *input = cyapa->input;
+	struct cyapa_reg_data data;
+	int i;
+	int ret;
+	int num_fingers;
+	unsigned int mask;
+
+	if (device_may_wakeup(dev))
+		pm_wakeup_event(dev, 0);
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
+	if (ret != sizeof(data))
+		goto irqhandled;
+
+	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
+	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
+	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
+		goto irqhandled;
+	}
+
+	mask = 0;
+	num_fingers = (data.finger_btn >> 4) & 0x0f;
+	for (i = 0; i < num_fingers; i++) {
+		const struct cyapa_touch *touch = &data.touches[i];
+		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
+		int slot = touch->id - 1;
+
+		mask |= (1 << slot);
+		input_mt_slot(input, slot);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+		input_report_abs(input, ABS_MT_POSITION_X,
+				 ((touch->xy_hi & 0xf0) << 4) | touch->x_lo);
+		input_report_abs(input, ABS_MT_POSITION_Y,
+				 ((touch->xy_hi & 0x0f) << 8) | touch->y_lo);
+		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
+	}
+
+	/* Invalidate all unreported slots */
+	for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
+		if (mask & (1 << i))
+			continue;
+		input_mt_slot(input, i);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
+	}
+
+	input_mt_report_pointer_emulation(input, true);
+	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
+		input_report_key(input, BTN_LEFT,
+				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
+	}
+	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK) {
+		input_report_key(input, BTN_MIDDLE,
+				 !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
+	}
+	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK) {
+		input_report_key(input, BTN_RIGHT,
+				 !!(data.finger_btn & OP_DATA_RIGHT_BTN));
+	}
+	input_sync(input);
+
+irqhandled:
+	return IRQ_HANDLED;
+}
+
+static int cyapa_create_input_dev(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	struct input_dev *input;
+
+	input = cyapa->input = input_allocate_device();
+	if (!input) {
+		dev_err(dev, "allocate memory for input device failed\n");
+		return -ENOMEM;
+	}
+
+	input->name = CYAPA_NAME;
+	input->phys = cyapa->phys;
+	input->id.bustype = BUS_I2C;
+	input->id.version = 1;
+	input->id.product = 0;  /* means any product in eventcomm. */
+	input->dev.parent = &cyapa->client->dev;
+
+	input_set_drvdata(input, cyapa);
+
+	__set_bit(EV_ABS, input->evbit);
+
+	/*
+	 * set and report not-MT axes to support synaptics X Driver.
+	 * When multi-fingers on trackpad, only the first finger touch
+	 * will be reported as X/Y axes values.
+	 */
+	input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
+
+	/* finger position */
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
+	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
+	if (ret < 0) {
+		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
+		goto err_free_device;
+	}
+
+	if (cyapa->physical_size_x && cyapa->physical_size_y) {
+		input_abs_set_res(input, ABS_X,
+			cyapa->max_abs_x / cyapa->physical_size_x);
+		input_abs_set_res(input, ABS_Y,
+			cyapa->max_abs_y / cyapa->physical_size_y);
+		input_abs_set_res(input, ABS_MT_POSITION_X,
+			cyapa->max_abs_x / cyapa->physical_size_x);
+		input_abs_set_res(input, ABS_MT_POSITION_Y,
+			cyapa->max_abs_y / cyapa->physical_size_y);
+	}
+
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(BTN_TOUCH, input->keybit);
+	__set_bit(BTN_TOOL_FINGER, input->keybit);
+	__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
+	__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
+	__set_bit(BTN_TOOL_QUADTAP, input->keybit);
+	__set_bit(BTN_TOOL_QUINTTAP, input->keybit);
+
+	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
+		__set_bit(BTN_LEFT, input->keybit);
+	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
+		__set_bit(BTN_MIDDLE, input->keybit);
+	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
+		__set_bit(BTN_RIGHT, input->keybit);
+
+	__set_bit(INPUT_PROP_POINTER, input->propbit);
+	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
+
+	/* Register the device in input subsystem */
+	ret = input_register_device(input);
+	if (ret) {
+		dev_err(dev, "input device register failed, %d\n", ret);
+		goto err_free_device;
+	}
+	return 0;
+
+err_free_device:
+	input_free_device(input);
+	cyapa->input = NULL;
+	return ret;
+}
+
+static int __devinit cyapa_probe(struct i2c_client *client,
+				 const struct i2c_device_id *dev_id)
+{
+	int ret;
+	struct cyapa *cyapa;
+	struct device *dev = &client->dev;
+
+	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
+	if (!cyapa) {
+		dev_err(dev, "allocate memory for cyapa failed\n");
+		return -ENOMEM;
+	}
+
+	cyapa->gen = CYAPA_GEN3;
+	cyapa->client = client;
+	i2c_set_clientdata(client, cyapa);
+	cyapa->phys = kasprintf(GFP_KERNEL, "i2c-%d-%04x/input0",
+				client->adapter->nr, client->addr);
+	if (!cyapa->phys) {
+		ret = -ENOMEM;
+		goto err_mem_free;
+	}
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+	ret = cyapa_check_is_operational(cyapa);
+	if (ret == -ETIMEDOUT) {
+		dev_err(dev, "no device detected, %d\n", ret);
+		goto err_mem_free;
+	} else if (ret) {
+		dev_err(dev, "device detected, but not operational, %d\n", ret);
+		goto err_mem_free;
+	}
+	ret = cyapa_create_input_dev(cyapa);
+	if (ret) {
+		dev_err(dev, "create input_dev instance failed, %d\n", ret);
+		goto err_mem_free;
+	}
+
+	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+	if (ret) {
+		dev_err(dev, "set active power failed, %d\n", ret);
+		goto err_unregister_device;
+	}
+
+	cyapa->irq = client->irq;
+	ret = request_threaded_irq(cyapa->irq,
+				   NULL,
+				   cyapa_irq,
+				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				   "cyapa",
+				   cyapa);
+	if (ret) {
+		dev_err(dev, "IRQ request failed: %d\n, ", ret);
+		goto err_unregister_device;
+	}
+
+	return 0;
+
+err_unregister_device:
+	input_unregister_device(cyapa->input);
+err_mem_free:
+	kfree(cyapa->phys);
+	kfree(cyapa);
+
+	return ret;
+}
+
+static int __devexit cyapa_remove(struct i2c_client *client)
+{
+	struct cyapa *cyapa = i2c_get_clientdata(client);
+
+	free_irq(cyapa->irq, cyapa);
+	input_unregister_device(cyapa->input);
+	kfree(cyapa->phys);
+	kfree(cyapa);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cyapa_suspend(struct device *dev)
+{
+	int ret;
+	u8 power_mode;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	disable_irq(cyapa->irq);
+
+	/*
+	 * Set trackpad device to idle mode if wakeup is allowed,
+	 * otherwise turn off.
+	 */
+	power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
+					    : PWR_MODE_OFF;
+	ret = cyapa_set_power_mode(cyapa, power_mode);
+	if (ret < 0)
+		dev_err(dev, "set power mode failed, %d\n", ret);
+
+	if (device_may_wakeup(dev))
+		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
+	return 0;
+}
+
+static int cyapa_resume(struct device *dev)
+{
+	int ret;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev) && cyapa->irq_wake)
+		disable_irq_wake(cyapa->irq);
+
+	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+	if (ret)
+		dev_warn(dev, "resume active power failed, %d\n", ret);
+
+	enable_irq(cyapa->irq);
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
+
+static const struct i2c_device_id cyapa_id_table[] = {
+	{ "cyapa", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
+
+static struct i2c_driver cyapa_driver = {
+	.driver = {
+		.name = "cyapa",
+		.owner = THIS_MODULE,
+		.pm = &cyapa_pm_ops,
+	},
+
+	.probe = cyapa_probe,
+	.remove = __devexit_p(cyapa_remove),
+	.id_table = cyapa_id_table,
+};
+
+module_i2c_driver(cyapa_driver);
+
+MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
+MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
+MODULE_LICENSE("GPL");
-- 
1.7.7.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06  0:48   ` [PATCH v2 1/1] " Benson Leung
@ 2012-12-06  7:48     ` Dmitry Torokhov
  2012-12-06  8:29       ` Jean Delvare
  2012-12-06 14:59     ` Henrik Rydberg
  1 sibling, 1 reply; 14+ messages in thread
From: Dmitry Torokhov @ 2012-12-06  7:48 UTC (permalink / raw)
  To: Benson Leung
  Cc: rydberg, linux-input, linux-kernel, djkurtz, olofj, dudl, Jean Delvare

Hi Benson,

On Wed, Dec 05, 2012 at 04:48:19PM -0800, Benson Leung wrote:
> This patch introduces a driver for Cypress All Points Addressable
> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
> 
> This device is compatible with MT protocol type B, providing identifiable
> contacts.
> 
> Signed-off-by: Dudley Du <dudl@cypress.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Benson Leung <bleung@chromium.org>
> ---
>  Version history :
> v2 : * Removed firmware update.
>      * Removed sysfs properties related to firmware update and power mode.
>      * Folded cyapa_detect into cyapa_probe.
>      * Added support for middle and right mechanical buttons, if they exist.
>      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
>          a power mode change from colliding with a read of tracking data.
>      * Made cyapa_get_state more reliable.
>      * Use IRQF_ONESHOT for threaded irq
>      * Simplified cyapa_set_power_mode.
>      * Removed extra kernel-doc style comments
>      * Removed dev_dbg messages.
>      * Cleaned up unused includes.
>      * Cleaned up unused #defines
> v1 : Initial

First of all - this version is excellent compared to the previous ones
posted. I have just a few quesutions (and of course I'd like Henrik to
look over MT handlingi and Jean for I2C bits).

> ---
>  drivers/input/mouse/Kconfig  |   12 +
>  drivers/input/mouse/Makefile |    1 +
>  drivers/input/mouse/cyapa.c  |  838 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 851 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/input/mouse/cyapa.c
> 
> diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
> index cd6268c..23db30a 100644
> --- a/drivers/input/mouse/Kconfig
> +++ b/drivers/input/mouse/Kconfig
> @@ -193,6 +193,18 @@ config MOUSE_BCM5974
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called bcm5974.
>  
> +config MOUSE_CYAPA
> +	tristate "Cypress APA I2C Trackpad support"
> +	depends on I2C
> +	help
> +	  This driver adds support for Cypress All Points Addressable (APA)
> +	  I2C Trackpads, including the ones used in 2012 Samsung Chromebooks.
> +
> +	  Say Y here if you have a Cypress APA I2C Trackpad.
> +
> +	  To compile this driver as a module, choose M here: the module will be
> +	  called cyapa.
> +
>  config MOUSE_INPORT
>  	tristate "InPort/MS/ATIXL busmouse"
>  	depends on ISA
> diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
> index 46ba755..10b4773 100644
> --- a/drivers/input/mouse/Makefile
> +++ b/drivers/input/mouse/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
>  obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
>  obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
>  obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
> +obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
>  obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
>  obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
>  obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
> diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
> new file mode 100644
> index 0000000..08cf1ce
> --- /dev/null
> +++ b/drivers/input/mouse/cyapa.c
> @@ -0,0 +1,838 @@
> +/*
> + * Cypress APA trackpad with I2C interface
> + *
> + * Author: Dudley Du <dudl@cypress.com>
> + * Further cleanup and restructuring by:
> + *   Daniel Kurtz <djkurtz@chromium.org>
> + *   Benson Leung <bleung@chromium.org>
> + *
> + * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
> + * Copyright (C) 2011-2012 Google, Inc.
> + *
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License.  See the file COPYING in the main directory of this archive for
> + * more details.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/input/mt.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +
> +/* APA trackpad firmware generation */
> +#define CYAPA_GEN3   0x03   /* support MT-protocol B with tracking ID. */
> +
> +#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
> +
> +/* commands for read/write registers of Cypress trackpad */
> +#define CYAPA_CMD_SOFT_RESET       0x00
> +#define CYAPA_CMD_POWER_MODE       0x01
> +#define CYAPA_CMD_DEV_STATUS       0x02
> +#define CYAPA_CMD_GROUP_DATA       0x03
> +#define CYAPA_CMD_GROUP_CMD        0x04
> +#define CYAPA_CMD_GROUP_QUERY      0x05
> +#define CYAPA_CMD_BL_STATUS        0x06
> +#define CYAPA_CMD_BL_HEAD          0x07
> +#define CYAPA_CMD_BL_CMD           0x08
> +#define CYAPA_CMD_BL_DATA          0x09
> +#define CYAPA_CMD_BL_ALL           0x0a
> +#define CYAPA_CMD_BLK_PRODUCT_ID   0x0b
> +#define CYAPA_CMD_BLK_HEAD         0x0c
> +
> +/* report data start reg offset address. */
> +#define DATA_REG_START_OFFSET  0x0000
> +
> +#define BL_HEAD_OFFSET 0x00
> +#define BL_DATA_OFFSET 0x10
> +
> +/*
> + * Operational Device Status Register
> + *
> + * bit 7: Valid interrupt source
> + * bit 6 - 4: Reserved
> + * bit 3 - 2: Power status
> + * bit 1 - 0: Device status
> + */
> +#define REG_OP_STATUS     0x00
> +#define OP_STATUS_SRC     0x80
> +#define OP_STATUS_POWER   0x0c
> +#define OP_STATUS_DEV     0x03
> +#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
> +
> +/*
> + * Operational Finger Count/Button Flags Register
> + *
> + * bit 7 - 4: Number of touched finger
> + * bit 3: Valid data
> + * bit 2: Middle Physical Button
> + * bit 1: Right Physical Button
> + * bit 0: Left physical Button
> + */
> +#define REG_OP_DATA1       0x01
> +#define OP_DATA_VALID      0x08
> +#define OP_DATA_MIDDLE_BTN 0x04
> +#define OP_DATA_RIGHT_BTN  0x02
> +#define OP_DATA_LEFT_BTN   0x01
> +#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
> +			  OP_DATA_LEFT_BTN)
> +
> +/*
> + * Bootloader Status Register
> + *
> + * bit 7: Busy
> + * bit 6 - 5: Reserved
> + * bit 4: Bootloader running
> + * bit 3 - 1: Reserved
> + * bit 0: Checksum valid
> + */
> +#define REG_BL_STATUS        0x01
> +#define BL_STATUS_BUSY       0x80
> +#define BL_STATUS_RUNNING    0x10
> +#define BL_STATUS_DATA_VALID 0x08
> +#define BL_STATUS_CSUM_VALID 0x01
> +
> +/*
> + * Bootloader Error Register
> + *
> + * bit 7: Invalid
> + * bit 6: Invalid security key
> + * bit 5: Bootloading
> + * bit 4: Command checksum
> + * bit 3: Flash protection error
> + * bit 2: Flash checksum error
> + * bit 1 - 0: Reserved
> + */
> +#define REG_BL_ERROR         0x02
> +#define BL_ERROR_INVALID     0x80
> +#define BL_ERROR_INVALID_KEY 0x40
> +#define BL_ERROR_BOOTLOADING 0x20
> +#define BL_ERROR_CMD_CSUM    0x10
> +#define BL_ERROR_FLASH_PROT  0x08
> +#define BL_ERROR_FLASH_CSUM  0x04
> +
> +#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
> +#define BLK_HEAD_BYTES 32
> +
> +#define PRODUCT_ID_SIZE  16
> +#define QUERY_DATA_SIZE  27
> +#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
> +
> +#define REG_OFFSET_DATA_BASE     0x0000
> +#define REG_OFFSET_COMMAND_BASE  0x0028
> +#define REG_OFFSET_QUERY_BASE    0x002a
> +
> +#define CAPABILITY_LEFT_BTN_MASK	(0x01 << 3)
> +#define CAPABILITY_RIGHT_BTN_MASK	(0x01 << 4)
> +#define CAPABILITY_MIDDLE_BTN_MASK	(0x01 << 5)
> +#define CAPABILITY_BTN_MASK  (CAPABILITY_LEFT_BTN_MASK | \
> +			      CAPABILITY_RIGHT_BTN_MASK | \
> +			      CAPABILITY_MIDDLE_BTN_MASK)
> +
> +#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
> +
> +#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
> +
> +#define PWR_MODE_MASK   0xfc
> +#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
> +#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
> +#define PWR_MODE_OFF         (0x00 << 2)
> +
> +#define PWR_STATUS_MASK      0x0c
> +#define PWR_STATUS_ACTIVE    (0x03 << 2)
> +#define PWR_STATUS_IDLE      (0x02 << 2)
> +#define PWR_STATUS_OFF       (0x00 << 2)
> +
> +/*
> + * CYAPA trackpad device states.
> + * Used in register 0x00, bit1-0, DeviceStatus field.
> + * Other values indicate device is in an abnormal state and must be reset.
> + */
> +#define CYAPA_DEV_NORMAL  0x03
> +#define CYAPA_DEV_BUSY    0x01
> +
> +enum cyapa_state {
> +	CYAPA_STATE_OP,
> +	CYAPA_STATE_BL_IDLE,
> +	CYAPA_STATE_BL_ACTIVE,
> +	CYAPA_STATE_BL_BUSY,
> +	CYAPA_STATE_NO_DEVICE,
> +};
> +
> +
> +struct cyapa_touch {
> +	/*
> +	 * high bits or x/y position value
> +	 * bit 7 - 4: high 4 bits of x position value
> +	 * bit 3 - 0: high 4 bits of y position value
> +	 */
> +	u8 xy_hi;
> +	u8 x_lo;  /* low 8 bits of x position value. */
> +	u8 y_lo;  /* low 8 bits of y position value. */
> +	u8 pressure;
> +	/* id range is 1 - 15.  It is incremented with every new touch. */
> +	u8 id;
> +} __packed;
> +
> +/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
> +#define CYAPA_MAX_MT_SLOTS  15
> +
> +struct cyapa_reg_data {
> +	/*
> +	 * bit 0 - 1: device status
> +	 * bit 3 - 2: power mode
> +	 * bit 6 - 4: reserved
> +	 * bit 7: interrupt valid bit
> +	 */
> +	u8 device_status;
> +	/*
> +	 * bit 7 - 4: number of fingers currently touching pad
> +	 * bit 3: valid data check bit
> +	 * bit 2: middle mechanism button state if exists
> +	 * bit 1: right mechanism button state if exists
> +	 * bit 0: left mechanism button state if exists
> +	 */
> +	u8 finger_btn;
> +	/* CYAPA reports up to 5 touches per packet. */
> +	struct cyapa_touch touches[5];
> +} __packed;
> +
> +/* The main device structure */
> +struct cyapa {
> +	enum cyapa_state state;
> +
> +	struct i2c_client *client;
> +	struct input_dev *input;
> +	char *phys;	/* device physical location */

I would simply allocate a static array of 32 or 64 bytes here and be
done with it.

> +	int irq;
> +	bool irq_wake;  /* irq wake is enabled */
> +
> +	/* read from query data region. */
> +	char product_id[16];
> +	u8 btn_capability;
> +	u8 gen;
> +	int max_abs_x;
> +	int max_abs_y;
> +	int physical_size_x;
> +	int physical_size_y;
> +};
> +
> +static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
> +		0x04, 0x05, 0x06, 0x07 };
> +static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
> +		0x05, 0x06, 0x07 };
> +
> +struct cyapa_cmd_len {
> +	u8 cmd;
> +	u8 len;
> +};
> +
> +static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
> +	{CYAPA_OFFSET_SOFT_RESET, 1},
> +	{REG_OFFSET_COMMAND_BASE + 1, 1},
> +	{REG_OFFSET_DATA_BASE, 1},
> +	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
> +	{REG_OFFSET_COMMAND_BASE, 0},
> +	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
> +	{BL_HEAD_OFFSET, 3},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_DATA_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 32},
> +	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
> +	{REG_OFFSET_DATA_BASE, 32}
> +};
> +
> +static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
> +					u8 *values)
> +{
> +	return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);

Does it have to be SMBUS? If it does you need to check the capabilities
in probe(). 

> +}
> +
> +static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
> +					 size_t len, const u8 *values)
> +{
> +	return i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
> +}
> +
> +static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +
> +	return i2c_smbus_read_byte_data(cyapa->client, cmd);
> +}
> +
> +static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +
> +	return i2c_smbus_write_byte_data(cyapa->client, cmd, value);
> +}
> +
> +static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +	size_t len = cyapa_i2c_cmds[cmd_idx].len;
> +
> +	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
> +}
> +
> +/*
> + * Query device for its current operating state.
> + *
> + */
> +static int cyapa_get_state(struct cyapa *cyapa)
> +{
> +	int ret;
> +	u8 status[BL_STATUS_SIZE];
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +
> +	/*
> +	 * Get trackpad status by reading 3 registers starting from 0.
> +	 * If the device is in the bootloader, this will be BL_HEAD.
> +	 * If the device is in operation mode, this will be the DATA regs.
> +	 *
> +	 */
> +	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
> +				       status);
> +	if (ret != BL_STATUS_SIZE)
> +		goto error;
> +
> +	if ((status[REG_OP_STATUS] & OP_STATUS_SRC) == OP_STATUS_SRC) {
> +		switch (status[REG_OP_STATUS] & OP_STATUS_DEV) {
> +		case CYAPA_DEV_NORMAL:
> +		case CYAPA_DEV_BUSY:
> +			cyapa->state = CYAPA_STATE_OP;
> +			break;
> +		default:
> +			ret = -EAGAIN;
> +			goto error;
> +		}
> +	} else {
> +		if (status[REG_BL_STATUS] & BL_STATUS_BUSY)
> +			cyapa->state = CYAPA_STATE_BL_BUSY;
> +		else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING)
> +			cyapa->state = CYAPA_STATE_BL_ACTIVE;
> +		else
> +			cyapa->state = CYAPA_STATE_BL_IDLE;
> +	}
> +
> +	return 0;
> +error:
> +	return (ret < 0) ? ret : -EAGAIN;
> +}
> +
> +/*
> + * Poll device for its status in a loop, waiting up to timeout for a response.
> + *
> + * When the device switches state, it usually takes ~300 ms.
> + * However, when running a new firmware image, the device must calibrate its
> + * sensors, which can take as long as 2 seconds.
> + *
> + * Note: The timeout has granularity of the polling rate, which is 100 ms.
> + *
> + * Returns:
> + *   0 when the device eventually responds with a valid non-busy state.
> + *   -ETIMEDOUT if device never responds (too many -EAGAIN)
> + *   < 0    other errors
> + */
> +static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
> +{
> +	int ret;
> +	int tries = timeout / 100;
> +
> +	ret = cyapa_get_state(cyapa);
> +	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
> +		msleep(100);
> +		ret = cyapa_get_state(cyapa);
> +	}
> +	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
> +}
> +
> +static int cyapa_bl_deactivate(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
> +					bl_deactivate);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* wait for bootloader to switch to idle state; should take < 100ms */
> +	msleep(100);
> +	ret = cyapa_poll_state(cyapa, 500);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_BL_IDLE)
> +		return -EAGAIN;
> +	return 0;
> +}
> +
> +/*
> + * Exit bootloader
> + *
> + * Send bl_exit command, then wait 50 - 100 ms to let device transition to
> + * operational mode.  If this is the first time the device's firmware is
> + * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
> + * the device's new state for up to 2 seconds.
> + *
> + * Returns:
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
> + *   0       device is supported and in operational mode
> + */
> +static int cyapa_bl_exit(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * Wait for bootloader to exit, and operation mode to start.
> +	 * Normally, this takes at least 50 ms.
> +	 */
> +	usleep_range(50000, 100000);
> +	/*
> +	 * In addition, when a device boots for the first time after being
> +	 * updated to new firmware, it must first calibrate its sensors, which
> +	 * can take up to an additional 2 seconds.
> +	 */
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EAGAIN;
> +
> +	return 0;
> +}
> +
> +/*
> + * Set device power mode
> + *
> + */
> +static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 power;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return 0;
> +
> +	ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
> +	if (ret < 0)
> +		return ret;
> +
> +	power = ret & ~PWR_MODE_MASK;
> +	power |= power_mode & PWR_MODE_MASK;
> +	ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
> +	if (ret < 0)
> +		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
> +			power_mode, ret);
> +	return ret;
> +}
> +
> +static int cyapa_get_query_data(struct cyapa *cyapa)
> +{
> +	u8 query_data[QUERY_DATA_SIZE];
> +	int ret;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EBUSY;
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
> +	if (ret < 0)
> +		return ret;
> +	if (ret != QUERY_DATA_SIZE)
> +		return -EIO;
> +
> +	memcpy(&cyapa->product_id[0], &query_data[0], 5);
> +	cyapa->product_id[5] = '-';
> +	memcpy(&cyapa->product_id[6], &query_data[5], 6);
> +	cyapa->product_id[12] = '-';
> +	memcpy(&cyapa->product_id[13], &query_data[11], 2);
> +	cyapa->product_id[15] = '\0';
> +
> +	cyapa->btn_capability = query_data[19] & CAPABILITY_BTN_MASK;
> +
> +	cyapa->gen = query_data[20] & 0x0f;
> +
> +	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
> +	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
> +
> +	cyapa->physical_size_x =
> +		((query_data[24] & 0xf0) << 4) | query_data[25];
> +	cyapa->physical_size_y =
> +		((query_data[24] & 0x0f) << 8) | query_data[26];
> +
> +	return 0;
> +}
> +
> +/*
> + * Check if device is operational.
> + *
> + * An operational device is responding, has exited bootloader, and has
> + * firmware supported by this driver.
> + *
> + * Returns:
> + *   -EBUSY  no device or in bootloader
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is still in bootloader
> + *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
> + *   -EINVAL device is in operational mode, but not supported by this driver
> + *   0       device is supported
> + */
> +static int cyapa_check_is_operational(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	static const char unique_str[] = "CYTRA";
> +	int ret;
> +
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	switch (cyapa->state) {
> +	case CYAPA_STATE_BL_ACTIVE:
> +		ret = cyapa_bl_deactivate(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_BL_IDLE:
> +		ret = cyapa_bl_exit(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_OP:
> +		ret = cyapa_get_query_data(cyapa);
> +		if (ret < 0)
> +			return ret;
> +
> +		/* only support firmware protocol gen3 */
> +		if (cyapa->gen != CYAPA_GEN3) {
> +			dev_err(dev, "unsupported protocol version (%d)",
> +				cyapa->gen);
> +			return -EINVAL;
> +		}
> +
> +		/* only support product ID starting with CYTRA */
> +		if (memcmp(cyapa->product_id, unique_str,
> +			   sizeof(unique_str) - 1) != 0) {
> +			dev_err(dev, "unsupported product ID (%s)\n",
> +				cyapa->product_id);
> +			return -EINVAL;
> +		}
> +		return 0;
> +
> +	default:
> +		return -EIO;
> +	}
> +	return 0;
> +}
> +
> +static irqreturn_t cyapa_irq(int irq, void *dev_id)
> +{
> +	struct cyapa *cyapa = dev_id;
> +	struct device *dev = &cyapa->client->dev;
> +	struct input_dev *input = cyapa->input;
> +	struct cyapa_reg_data data;
> +	int i;
> +	int ret;
> +	int num_fingers;
> +	unsigned int mask;
> +
> +	if (device_may_wakeup(dev))
> +		pm_wakeup_event(dev, 0);
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
> +	if (ret != sizeof(data))
> +		goto irqhandled;
> +
> +	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
> +	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
> +	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
> +		goto irqhandled;
> +	}
> +
> +	mask = 0;
> +	num_fingers = (data.finger_btn >> 4) & 0x0f;
> +	for (i = 0; i < num_fingers; i++) {
> +		const struct cyapa_touch *touch = &data.touches[i];
> +		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
> +		int slot = touch->id - 1;
> +
> +		mask |= (1 << slot);
> +		input_mt_slot(input, slot);
> +		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
> +		input_report_abs(input, ABS_MT_POSITION_X,
> +				 ((touch->xy_hi & 0xf0) << 4) | touch->x_lo);
> +		input_report_abs(input, ABS_MT_POSITION_Y,
> +				 ((touch->xy_hi & 0x0f) << 8) | touch->y_lo);
> +		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
> +	}
> +
> +	/* Invalidate all unreported slots */
> +	for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
> +		if (mask & (1 << i))
> +			continue;
> +		input_mt_slot(input, i);
> +		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
> +	}
> +
> +	input_mt_report_pointer_emulation(input, true);
> +	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
> +		input_report_key(input, BTN_LEFT,
> +				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
> +	}
> +	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK) {
> +		input_report_key(input, BTN_MIDDLE,
> +				 !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
> +	}
> +	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK) {
> +		input_report_key(input, BTN_RIGHT,
> +				 !!(data.finger_btn & OP_DATA_RIGHT_BTN));
> +	}
> +	input_sync(input);
> +
> +irqhandled:
> +	return IRQ_HANDLED;
> +}
> +
> +static int cyapa_create_input_dev(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	struct input_dev *input;
> +
> +	input = cyapa->input = input_allocate_device();
> +	if (!input) {
> +		dev_err(dev, "allocate memory for input device failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = CYAPA_NAME;
> +	input->phys = cyapa->phys;
> +	input->id.bustype = BUS_I2C;
> +	input->id.version = 1;
> +	input->id.product = 0;  /* means any product in eventcomm. */
> +	input->dev.parent = &cyapa->client->dev;
> +
> +	input_set_drvdata(input, cyapa);
> +
> +	__set_bit(EV_ABS, input->evbit);
> +
> +	/*
> +	 * set and report not-MT axes to support synaptics X Driver.
> +	 * When multi-fingers on trackpad, only the first finger touch
> +	 * will be reported as X/Y axes values.
> +	 */
> +	input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
> +	input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
> +	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
> +
> +	/* finger position */
> +	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
> +	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
> +	if (ret < 0) {
> +		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +
> +	if (cyapa->physical_size_x && cyapa->physical_size_y) {
> +		input_abs_set_res(input, ABS_X,
> +			cyapa->max_abs_x / cyapa->physical_size_x);
> +		input_abs_set_res(input, ABS_Y,
> +			cyapa->max_abs_y / cyapa->physical_size_y);
> +		input_abs_set_res(input, ABS_MT_POSITION_X,
> +			cyapa->max_abs_x / cyapa->physical_size_x);
> +		input_abs_set_res(input, ABS_MT_POSITION_Y,
> +			cyapa->max_abs_y / cyapa->physical_size_y);
> +	}
> +
> +	__set_bit(EV_KEY, input->evbit);
> +	__set_bit(BTN_TOUCH, input->keybit);
> +	__set_bit(BTN_TOOL_FINGER, input->keybit);
> +	__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
> +	__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
> +	__set_bit(BTN_TOOL_QUADTAP, input->keybit);
> +	__set_bit(BTN_TOOL_QUINTTAP, input->keybit);
> +
> +	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
> +		__set_bit(BTN_LEFT, input->keybit);
> +	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
> +		__set_bit(BTN_MIDDLE, input->keybit);
> +	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
> +		__set_bit(BTN_RIGHT, input->keybit);
> +
> +	__set_bit(INPUT_PROP_POINTER, input->propbit);
> +	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);

I do not think you should set INPUT_PROP_BUTTONPAD if device has
physical buttons.

> +
> +	/* Register the device in input subsystem */
> +	ret = input_register_device(input);
> +	if (ret) {
> +		dev_err(dev, "input device register failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +	return 0;
> +
> +err_free_device:
> +	input_free_device(input);
> +	cyapa->input = NULL;
> +	return ret;
> +}
> +
> +static int __devinit cyapa_probe(struct i2c_client *client,
> +				 const struct i2c_device_id *dev_id)
> +{
> +	int ret;
> +	struct cyapa *cyapa;
> +	struct device *dev = &client->dev;
> +
> +	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
> +	if (!cyapa) {
> +		dev_err(dev, "allocate memory for cyapa failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	cyapa->gen = CYAPA_GEN3;
> +	cyapa->client = client;
> +	i2c_set_clientdata(client, cyapa);
> +	cyapa->phys = kasprintf(GFP_KERNEL, "i2c-%d-%04x/input0",
> +				client->adapter->nr, client->addr);
> +	if (!cyapa->phys) {
> +		ret = -ENOMEM;
> +		goto err_mem_free;
> +	}
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +	ret = cyapa_check_is_operational(cyapa);
> +	if (ret == -ETIMEDOUT) {
> +		dev_err(dev, "no device detected, %d\n", ret);
> +		goto err_mem_free;
> +	} else if (ret) {
> +		dev_err(dev, "device detected, but not operational, %d\n", ret);
> +		goto err_mem_free;

You already reporting the error code; just collapse these 2 branches.

> +	}
> +	ret = cyapa_create_input_dev(cyapa);
> +	if (ret) {
> +		dev_err(dev, "create input_dev instance failed, %d\n", ret);
> +		goto err_mem_free;
> +	}
> +
> +	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +	if (ret) {
> +		dev_err(dev, "set active power failed, %d\n", ret);
> +		goto err_unregister_device;
> +	}
> +
> +	cyapa->irq = client->irq;
> +	ret = request_threaded_irq(cyapa->irq,
> +				   NULL,
> +				   cyapa_irq,
> +				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +				   "cyapa",
> +				   cyapa);
> +	if (ret) {
> +		dev_err(dev, "IRQ request failed: %d\n, ", ret);
> +		goto err_unregister_device;
> +	}
> +
> +	return 0;
> +
> +err_unregister_device:
> +	input_unregister_device(cyapa->input);
> +err_mem_free:
> +	kfree(cyapa->phys);
> +	kfree(cyapa);
> +
> +	return ret;
> +}
> +
> +static int __devexit cyapa_remove(struct i2c_client *client)

Mainline is getting rid of __devinit/__devexit/__devexit_p.

> +{
> +	struct cyapa *cyapa = i2c_get_clientdata(client);
> +
> +	free_irq(cyapa->irq, cyapa);
> +	input_unregister_device(cyapa->input);

Maybe you should put the device in low pwoer mode here.

> +	kfree(cyapa->phys);
> +	kfree(cyapa);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cyapa_suspend(struct device *dev)
> +{
> +	int ret;
> +	u8 power_mode;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	disable_irq(cyapa->irq);
> +
> +	/*
> +	 * Set trackpad device to idle mode if wakeup is allowed,
> +	 * otherwise turn off.
> +	 */
> +	power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
> +					    : PWR_MODE_OFF;
> +	ret = cyapa_set_power_mode(cyapa, power_mode);
> +	if (ret < 0)
> +		dev_err(dev, "set power mode failed, %d\n", ret);
> +
> +	if (device_may_wakeup(dev))
> +		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
> +	return 0;
> +}
> +
> +static int cyapa_resume(struct device *dev)
> +{
> +	int ret;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev) && cyapa->irq_wake)
> +		disable_irq_wake(cyapa->irq);
> +
> +	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +	if (ret)
> +		dev_warn(dev, "resume active power failed, %d\n", ret);
> +
> +	enable_irq(cyapa->irq);
> +	return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
> +
> +static const struct i2c_device_id cyapa_id_table[] = {
> +	{ "cyapa", 0 },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
> +
> +static struct i2c_driver cyapa_driver = {
> +	.driver = {
> +		.name = "cyapa",
> +		.owner = THIS_MODULE,
> +		.pm = &cyapa_pm_ops,
> +	},
> +
> +	.probe = cyapa_probe,
> +	.remove = __devexit_p(cyapa_remove),
> +	.id_table = cyapa_id_table,
> +};
> +
> +module_i2c_driver(cyapa_driver);
> +
> +MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
> +MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
> +MODULE_LICENSE("GPL");
> -- 
> 1.7.7.3
> 

Thanks!

-- 
Dmitry

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06  7:48     ` Dmitry Torokhov
@ 2012-12-06  8:29       ` Jean Delvare
  0 siblings, 0 replies; 14+ messages in thread
From: Jean Delvare @ 2012-12-06  8:29 UTC (permalink / raw)
  To: Dmitry Torokhov
  Cc: Benson Leung, rydberg, linux-input, linux-kernel, djkurtz, olofj, dudl

On Wed, 5 Dec 2012 23:48:17 -0800, Dmitry Torokhov wrote:
> Hi Benson,
> 
> On Wed, Dec 05, 2012 at 04:48:19PM -0800, Benson Leung wrote:
> > This patch introduces a driver for Cypress All Points Addressable
> > I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
> > 
> > This device is compatible with MT protocol type B, providing identifiable
> > contacts.
> > 
> > Signed-off-by: Dudley Du <dudl@cypress.com>
> > Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> > Signed-off-by: Benson Leung <bleung@chromium.org>
> > ---
> >  Version history :
> > v2 : * Removed firmware update.
> >      * Removed sysfs properties related to firmware update and power mode.
> >      * Folded cyapa_detect into cyapa_probe.
> >      * Added support for middle and right mechanical buttons, if they exist.
> >      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
> >          a power mode change from colliding with a read of tracking data.
> >      * Made cyapa_get_state more reliable.
> >      * Use IRQF_ONESHOT for threaded irq
> >      * Simplified cyapa_set_power_mode.
> >      * Removed extra kernel-doc style comments
> >      * Removed dev_dbg messages.
> >      * Cleaned up unused includes.
> >      * Cleaned up unused #defines
> > v1 : Initial
> 
> First of all - this version is excellent compared to the previous ones
> posted. I have just a few quesutions (and of course I'd like Henrik to
> look over MT handlingi and Jean for I2C bits).

I did not find any problem with the I2C bits.

> > (...)
> > +static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
> > +					u8 *values)
> > +{
> > +	return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
> 
> Does it have to be SMBUS? If it does you need to check the capabilities
> in probe(). 

Using SMBus calls is recommended as it increases portability of the
driver. I2C controllers can do SMBus but SMBus controllers can't do
I2C. Checking the capabilities is needed in both cases anyway, as you
can't assume anything from an i2c_adapter.

-- 
Jean Delvare

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06  0:48   ` [PATCH v2 1/1] " Benson Leung
  2012-12-06  7:48     ` Dmitry Torokhov
@ 2012-12-06 14:59     ` Henrik Rydberg
  2012-12-07 22:52       ` Benson Leung
  1 sibling, 1 reply; 14+ messages in thread
From: Henrik Rydberg @ 2012-12-06 14:59 UTC (permalink / raw)
  To: Benson Leung
  Cc: dmitry.torokhov, linux-input, linux-kernel, djkurtz, olofj, dudl

Hi Benson,

> This patch introduces a driver for Cypress All Points Addressable
> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
> 
> This device is compatible with MT protocol type B, providing identifiable
> contacts.
> 
> Signed-off-by: Dudley Du <dudl@cypress.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Benson Leung <bleung@chromium.org>
> ---
>  Version history :
> v2 : * Removed firmware update.
>      * Removed sysfs properties related to firmware update and power mode.
>      * Folded cyapa_detect into cyapa_probe.
>      * Added support for middle and right mechanical buttons, if they exist.
>      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
>          a power mode change from colliding with a read of tracking data.
>      * Made cyapa_get_state more reliable.
>      * Use IRQF_ONESHOT for threaded irq
>      * Simplified cyapa_set_power_mode.
>      * Removed extra kernel-doc style comments
>      * Removed dev_dbg messages.
>      * Cleaned up unused includes.
>      * Cleaned up unused #defines
> v1 : Initial
> ---
>  drivers/input/mouse/Kconfig  |   12 +
>  drivers/input/mouse/Makefile |    1 +
>  drivers/input/mouse/cyapa.c  |  838 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 851 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/input/mouse/cyapa.c

Looking good overall. The patch does not compile in 3.7, and it is
possible to further simplify the MT handling. The patch below takes
care of those changes. If it still works for you with this applied, we
should be fine.

Thanks,
Henrik

diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
index 08cf1ce..762fe9c 100644
--- a/drivers/input/mouse/cyapa.c
+++ b/drivers/input/mouse/cyapa.c
@@ -545,7 +545,6 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
 	int i;
 	int ret;
 	int num_fingers;
-	unsigned int mask;
 
 	if (device_may_wakeup(dev))
 		pm_wakeup_event(dev, 0);
@@ -560,14 +559,12 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
 		goto irqhandled;
 	}
 
-	mask = 0;
 	num_fingers = (data.finger_btn >> 4) & 0x0f;
 	for (i = 0; i < num_fingers; i++) {
 		const struct cyapa_touch *touch = &data.touches[i];
 		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
 		int slot = touch->id - 1;
 
-		mask |= (1 << slot);
 		input_mt_slot(input, slot);
 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
 		input_report_abs(input, ABS_MT_POSITION_X,
@@ -577,15 +574,8 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
 		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
 	}
 
-	/* Invalidate all unreported slots */
-	for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
-		if (mask & (1 << i))
-			continue;
-		input_mt_slot(input, i);
-		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
-	}
+	input_mt_sync_frame(input);
 
-	input_mt_report_pointer_emulation(input, true);
 	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
 		input_report_key(input, BTN_LEFT,
 				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
@@ -610,6 +600,9 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
 	int ret;
 	struct input_dev *input;
 
+	if (!cyapa->physical_size_x || !cyapa->physical_size_y)
+		return -EINVAL;
+
 	input = cyapa->input = input_allocate_device();
 	if (!input) {
 		dev_err(dev, "allocate memory for input device failed\n");
@@ -625,47 +618,17 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
 
 	input_set_drvdata(input, cyapa);
 
-	__set_bit(EV_ABS, input->evbit);
-
-	/*
-	 * set and report not-MT axes to support synaptics X Driver.
-	 * When multi-fingers on trackpad, only the first finger touch
-	 * will be reported as X/Y axes values.
-	 */
-	input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
-	input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
-	input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
-
 	/* finger position */
 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
 			     0);
 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
 			     0);
 	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
-	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
-	if (ret < 0) {
-		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
-		goto err_free_device;
-	}
-
-	if (cyapa->physical_size_x && cyapa->physical_size_y) {
-		input_abs_set_res(input, ABS_X,
-			cyapa->max_abs_x / cyapa->physical_size_x);
-		input_abs_set_res(input, ABS_Y,
-			cyapa->max_abs_y / cyapa->physical_size_y);
-		input_abs_set_res(input, ABS_MT_POSITION_X,
-			cyapa->max_abs_x / cyapa->physical_size_x);
-		input_abs_set_res(input, ABS_MT_POSITION_Y,
-			cyapa->max_abs_y / cyapa->physical_size_y);
-	}
 
-	__set_bit(EV_KEY, input->evbit);
-	__set_bit(BTN_TOUCH, input->keybit);
-	__set_bit(BTN_TOOL_FINGER, input->keybit);
-	__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
-	__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
-	__set_bit(BTN_TOOL_QUADTAP, input->keybit);
-	__set_bit(BTN_TOOL_QUINTTAP, input->keybit);
+	input_abs_set_res(input, ABS_MT_POSITION_X,
+			  cyapa->max_abs_x / cyapa->physical_size_x);
+	input_abs_set_res(input, ABS_MT_POSITION_Y,
+			  cyapa->max_abs_y / cyapa->physical_size_y);
 
 	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
 		__set_bit(BTN_LEFT, input->keybit);
@@ -674,9 +637,16 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
 	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
 		__set_bit(BTN_RIGHT, input->keybit);
 
-	__set_bit(INPUT_PROP_POINTER, input->propbit);
 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
 
+	/* handle pointer emulation and unused slots in core */
+	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
+				  INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
+	if (ret) {
+		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
+		goto err_free_device;
+	}
+
 	/* Register the device in input subsystem */
 	ret = input_register_device(input);
 	if (ret) {

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06 14:59     ` Henrik Rydberg
@ 2012-12-07 22:52       ` Benson Leung
  2012-12-08 12:39         ` Henrik Rydberg
  0 siblings, 1 reply; 14+ messages in thread
From: Benson Leung @ 2012-12-07 22:52 UTC (permalink / raw)
  To: Henrik Rydberg
  Cc: Dmitry Torokhov, linux-input, linux-kernel, Daniel Kurtz,
	Olof Johansson, Dudley Du

Hi Henrik,

I have applied your patch, but I found I still need this line in my
driver, otherwise, there are no ABS type event supported. Should the
core set this bit as well since it's certainly going to be dealing
with ABS data?

__set_bit(EV_ABS, input->evbit);

Otherwise, it works great on my Chromebook trackpad here.

Thanks a bunch,
Benson

On Thu, Dec 6, 2012 at 6:59 AM, Henrik Rydberg <rydberg@euromail.se> wrote:
> Hi Benson,
>
>> This patch introduces a driver for Cypress All Points Addressable
>> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
>>
>> This device is compatible with MT protocol type B, providing identifiable
>> contacts.
>>
>> Signed-off-by: Dudley Du <dudl@cypress.com>
>> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
>> Signed-off-by: Benson Leung <bleung@chromium.org>
>> ---
>>  Version history :
>> v2 : * Removed firmware update.
>>      * Removed sysfs properties related to firmware update and power mode.
>>      * Folded cyapa_detect into cyapa_probe.
>>      * Added support for middle and right mechanical buttons, if they exist.
>>      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
>>          a power mode change from colliding with a read of tracking data.
>>      * Made cyapa_get_state more reliable.
>>      * Use IRQF_ONESHOT for threaded irq
>>      * Simplified cyapa_set_power_mode.
>>      * Removed extra kernel-doc style comments
>>      * Removed dev_dbg messages.
>>      * Cleaned up unused includes.
>>      * Cleaned up unused #defines
>> v1 : Initial
>> ---
>>  drivers/input/mouse/Kconfig  |   12 +
>>  drivers/input/mouse/Makefile |    1 +
>>  drivers/input/mouse/cyapa.c  |  838 ++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 851 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/input/mouse/cyapa.c
>
> Looking good overall. The patch does not compile in 3.7, and it is
> possible to further simplify the MT handling. The patch below takes
> care of those changes. If it still works for you with this applied, we
> should be fine.
>
> Thanks,
> Henrik
>
> diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
> index 08cf1ce..762fe9c 100644
> --- a/drivers/input/mouse/cyapa.c
> +++ b/drivers/input/mouse/cyapa.c
> @@ -545,7 +545,6 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
>         int i;
>         int ret;
>         int num_fingers;
> -       unsigned int mask;
>
>         if (device_may_wakeup(dev))
>                 pm_wakeup_event(dev, 0);
> @@ -560,14 +559,12 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
>                 goto irqhandled;
>         }
>
> -       mask = 0;
>         num_fingers = (data.finger_btn >> 4) & 0x0f;
>         for (i = 0; i < num_fingers; i++) {
>                 const struct cyapa_touch *touch = &data.touches[i];
>                 /* Note: touch->id range is 1 to 15; slots are 0 to 14. */
>                 int slot = touch->id - 1;
>
> -               mask |= (1 << slot);
>                 input_mt_slot(input, slot);
>                 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
>                 input_report_abs(input, ABS_MT_POSITION_X,
> @@ -577,15 +574,8 @@ static irqreturn_t cyapa_irq(int irq, void *dev_id)
>                 input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
>         }
>
> -       /* Invalidate all unreported slots */
> -       for (i = 0; i < CYAPA_MAX_MT_SLOTS; i++) {
> -               if (mask & (1 << i))
> -                       continue;
> -               input_mt_slot(input, i);
> -               input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
> -       }
> +       input_mt_sync_frame(input);
>
> -       input_mt_report_pointer_emulation(input, true);
>         if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
>                 input_report_key(input, BTN_LEFT,
>                                  !!(data.finger_btn & OP_DATA_LEFT_BTN));
> @@ -610,6 +600,9 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
>         int ret;
>         struct input_dev *input;
>
> +       if (!cyapa->physical_size_x || !cyapa->physical_size_y)
> +               return -EINVAL;
> +
>         input = cyapa->input = input_allocate_device();
>         if (!input) {
>                 dev_err(dev, "allocate memory for input device failed\n");
> @@ -625,47 +618,17 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
>
>         input_set_drvdata(input, cyapa);
>
> -       __set_bit(EV_ABS, input->evbit);
> -
> -       /*
> -        * set and report not-MT axes to support synaptics X Driver.
> -        * When multi-fingers on trackpad, only the first finger touch
> -        * will be reported as X/Y axes values.
> -        */
> -       input_set_abs_params(input, ABS_X, 0, cyapa->max_abs_x, 0, 0);
> -       input_set_abs_params(input, ABS_Y, 0, cyapa->max_abs_y, 0, 0);
> -       input_set_abs_params(input, ABS_PRESSURE, 0, 255, 0, 0);
> -
>         /* finger position */
>         input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
>                              0);
>         input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
>                              0);
>         input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
> -       ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS);
> -       if (ret < 0) {
> -               dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
> -               goto err_free_device;
> -       }
> -
> -       if (cyapa->physical_size_x && cyapa->physical_size_y) {
> -               input_abs_set_res(input, ABS_X,
> -                       cyapa->max_abs_x / cyapa->physical_size_x);
> -               input_abs_set_res(input, ABS_Y,
> -                       cyapa->max_abs_y / cyapa->physical_size_y);
> -               input_abs_set_res(input, ABS_MT_POSITION_X,
> -                       cyapa->max_abs_x / cyapa->physical_size_x);
> -               input_abs_set_res(input, ABS_MT_POSITION_Y,
> -                       cyapa->max_abs_y / cyapa->physical_size_y);
> -       }
>
> -       __set_bit(EV_KEY, input->evbit);
> -       __set_bit(BTN_TOUCH, input->keybit);
> -       __set_bit(BTN_TOOL_FINGER, input->keybit);
> -       __set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
> -       __set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
> -       __set_bit(BTN_TOOL_QUADTAP, input->keybit);
> -       __set_bit(BTN_TOOL_QUINTTAP, input->keybit);
> +       input_abs_set_res(input, ABS_MT_POSITION_X,
> +                         cyapa->max_abs_x / cyapa->physical_size_x);
> +       input_abs_set_res(input, ABS_MT_POSITION_Y,
> +                         cyapa->max_abs_y / cyapa->physical_size_y);
>
>         if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
>                 __set_bit(BTN_LEFT, input->keybit);
> @@ -674,9 +637,16 @@ static int cyapa_create_input_dev(struct cyapa *cyapa)
>         if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
>                 __set_bit(BTN_RIGHT, input->keybit);
>
> -       __set_bit(INPUT_PROP_POINTER, input->propbit);
>         __set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
>
> +       /* handle pointer emulation and unused slots in core */
> +       ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
> +                                 INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
> +       if (ret) {
> +               dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
> +               goto err_free_device;
> +       }
> +
>         /* Register the device in input subsystem */
>         ret = input_register_device(input);
>         if (ret) {



-- 
Benson Leung
Software Engineer, Chrom* OS
bleung@chromium.org

^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 0/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-06  0:48 ` [PATCH v2 0/1] " Benson Leung
  2012-12-06  0:48   ` [PATCH v2 1/1] " Benson Leung
@ 2012-12-07 23:24   ` Benson Leung
  2012-12-07 23:24     ` [PATCH v3 1/1] " Benson Leung
  1 sibling, 1 reply; 14+ messages in thread
From: Benson Leung @ 2012-12-07 23:24 UTC (permalink / raw)
  To: khali, dmitry.torokhov, rydberg, linux-input, linux-kernel
  Cc: bleung, djkurtz, olofj, dudl

Thanks Dmitry, Jean, and Henrik.

Here's V3, which I have confirms compiles on input-next, and works
well on my Chromebook.

v3 : * Handle pointer emulation and unused slots in core
     * Fix compile fail on 3.7 for input_mt_init_slots (Thanks Rydberg)
     * Set BUTTONPAD property only if is a buttonpad based on capabilities.
     * Removed __devinit/__devexit/__devexit_p
     * Set to OFF power mode on cyapa_remove
     * Got rid of kasprintf'd physical location string for static one.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v3 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-07 23:24   ` [PATCH v3 0/1] " Benson Leung
@ 2012-12-07 23:24     ` Benson Leung
  2012-12-08 12:42       ` Henrik Rydberg
  2013-01-22 17:57       ` [v3,1/1] " Doug Anderson
  0 siblings, 2 replies; 14+ messages in thread
From: Benson Leung @ 2012-12-07 23:24 UTC (permalink / raw)
  To: khali, dmitry.torokhov, rydberg, linux-input, linux-kernel
  Cc: bleung, djkurtz, olofj, dudl

This patch introduces a driver for Cypress All Points Addressable
I2C Trackpad, including the ones in 2012 Samsung Chromebooks.

This device is compatible with MT protocol type B, providing identifiable
contacts.

Signed-off-by: Dudley Du <dudl@cypress.com>
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Benson Leung <bleung@chromium.org>
---
Version history :
v3 : * Handle pointer emulation and unused slots in core
     * Fix compile fail on 3.7 for input_mt_init_slots (Thanks Rydberg)
     * Set BUTTONPAD property only if is a buttonpad based on capabilities.
     * Removed __devinit/__devexit/__devexit_p
     * Set to OFF power mode on cyapa_remove
     * Got rid of kasprintf'd physical location string for static one.

v2 : * Removed firmware update.
     * Removed sysfs properties related to firmware update and power mode.
     * Folded cyapa_detect into cyapa_probe.
     * Added support for middle and right mechanical buttons, if they exist.
     * Rearranged disable_irq/enable_irq in suspend and resume to prevent
         a power mode change from colliding with a read of tracking data.
     * Made cyapa_get_state more reliable.
     * Use IRQF_ONESHOT for threaded irq
     * Simplified cyapa_set_power_mode.
     * Removed extra kernel-doc style comments
     * Removed dev_dbg messages.
     * Cleaned up unused includes.
     * Cleaned up unused #defines

v1 : Initial
---
 drivers/input/mouse/Kconfig  |   12 +
 drivers/input/mouse/Makefile |    1 +
 drivers/input/mouse/cyapa.c  |  803 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 816 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/mouse/cyapa.c

diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
index cd6268c..23db30a 100644
--- a/drivers/input/mouse/Kconfig
+++ b/drivers/input/mouse/Kconfig
@@ -193,6 +193,18 @@ config MOUSE_BCM5974
 	  To compile this driver as a module, choose M here: the
 	  module will be called bcm5974.
 
+config MOUSE_CYAPA
+	tristate "Cypress APA I2C Trackpad support"
+	depends on I2C
+	help
+	  This driver adds support for Cypress All Points Addressable (APA)
+	  I2C Trackpads, including the ones used in 2012 Samsung Chromebooks.
+
+	  Say Y here if you have a Cypress APA I2C Trackpad.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called cyapa.
+
 config MOUSE_INPORT
 	tristate "InPort/MS/ATIXL busmouse"
 	depends on ISA
diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
index 46ba755..10b4773 100644
--- a/drivers/input/mouse/Makefile
+++ b/drivers/input/mouse/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
 obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
 obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
 obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
+obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
 obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
 obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
 obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
new file mode 100644
index 0000000..0964583
--- /dev/null
+++ b/drivers/input/mouse/cyapa.c
@@ -0,0 +1,803 @@
+/*
+ * Cypress APA trackpad with I2C interface
+ *
+ * Author: Dudley Du <dudl@cypress.com>
+ * Further cleanup and restructuring by:
+ *   Daniel Kurtz <djkurtz@chromium.org>
+ *   Benson Leung <bleung@chromium.org>
+ *
+ * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Google, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+/* APA trackpad firmware generation */
+#define CYAPA_GEN3   0x03   /* support MT-protocol B with tracking ID. */
+
+#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
+
+/* commands for read/write registers of Cypress trackpad */
+#define CYAPA_CMD_SOFT_RESET       0x00
+#define CYAPA_CMD_POWER_MODE       0x01
+#define CYAPA_CMD_DEV_STATUS       0x02
+#define CYAPA_CMD_GROUP_DATA       0x03
+#define CYAPA_CMD_GROUP_CMD        0x04
+#define CYAPA_CMD_GROUP_QUERY      0x05
+#define CYAPA_CMD_BL_STATUS        0x06
+#define CYAPA_CMD_BL_HEAD          0x07
+#define CYAPA_CMD_BL_CMD           0x08
+#define CYAPA_CMD_BL_DATA          0x09
+#define CYAPA_CMD_BL_ALL           0x0a
+#define CYAPA_CMD_BLK_PRODUCT_ID   0x0b
+#define CYAPA_CMD_BLK_HEAD         0x0c
+
+/* report data start reg offset address. */
+#define DATA_REG_START_OFFSET  0x0000
+
+#define BL_HEAD_OFFSET 0x00
+#define BL_DATA_OFFSET 0x10
+
+/*
+ * Operational Device Status Register
+ *
+ * bit 7: Valid interrupt source
+ * bit 6 - 4: Reserved
+ * bit 3 - 2: Power status
+ * bit 1 - 0: Device status
+ */
+#define REG_OP_STATUS     0x00
+#define OP_STATUS_SRC     0x80
+#define OP_STATUS_POWER   0x0c
+#define OP_STATUS_DEV     0x03
+#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
+
+/*
+ * Operational Finger Count/Button Flags Register
+ *
+ * bit 7 - 4: Number of touched finger
+ * bit 3: Valid data
+ * bit 2: Middle Physical Button
+ * bit 1: Right Physical Button
+ * bit 0: Left physical Button
+ */
+#define REG_OP_DATA1       0x01
+#define OP_DATA_VALID      0x08
+#define OP_DATA_MIDDLE_BTN 0x04
+#define OP_DATA_RIGHT_BTN  0x02
+#define OP_DATA_LEFT_BTN   0x01
+#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
+			  OP_DATA_LEFT_BTN)
+
+/*
+ * Bootloader Status Register
+ *
+ * bit 7: Busy
+ * bit 6 - 5: Reserved
+ * bit 4: Bootloader running
+ * bit 3 - 1: Reserved
+ * bit 0: Checksum valid
+ */
+#define REG_BL_STATUS        0x01
+#define BL_STATUS_BUSY       0x80
+#define BL_STATUS_RUNNING    0x10
+#define BL_STATUS_DATA_VALID 0x08
+#define BL_STATUS_CSUM_VALID 0x01
+
+/*
+ * Bootloader Error Register
+ *
+ * bit 7: Invalid
+ * bit 6: Invalid security key
+ * bit 5: Bootloading
+ * bit 4: Command checksum
+ * bit 3: Flash protection error
+ * bit 2: Flash checksum error
+ * bit 1 - 0: Reserved
+ */
+#define REG_BL_ERROR         0x02
+#define BL_ERROR_INVALID     0x80
+#define BL_ERROR_INVALID_KEY 0x40
+#define BL_ERROR_BOOTLOADING 0x20
+#define BL_ERROR_CMD_CSUM    0x10
+#define BL_ERROR_FLASH_PROT  0x08
+#define BL_ERROR_FLASH_CSUM  0x04
+
+#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
+#define BLK_HEAD_BYTES 32
+
+#define PRODUCT_ID_SIZE  16
+#define QUERY_DATA_SIZE  27
+#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
+
+#define REG_OFFSET_DATA_BASE     0x0000
+#define REG_OFFSET_COMMAND_BASE  0x0028
+#define REG_OFFSET_QUERY_BASE    0x002a
+
+#define CAPABILITY_LEFT_BTN_MASK	(0x01 << 3)
+#define CAPABILITY_RIGHT_BTN_MASK	(0x01 << 4)
+#define CAPABILITY_MIDDLE_BTN_MASK	(0x01 << 5)
+#define CAPABILITY_BTN_MASK  (CAPABILITY_LEFT_BTN_MASK | \
+			      CAPABILITY_RIGHT_BTN_MASK | \
+			      CAPABILITY_MIDDLE_BTN_MASK)
+
+#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
+
+#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
+
+#define PWR_MODE_MASK   0xfc
+#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
+#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
+#define PWR_MODE_OFF         (0x00 << 2)
+
+#define PWR_STATUS_MASK      0x0c
+#define PWR_STATUS_ACTIVE    (0x03 << 2)
+#define PWR_STATUS_IDLE      (0x02 << 2)
+#define PWR_STATUS_OFF       (0x00 << 2)
+
+/*
+ * CYAPA trackpad device states.
+ * Used in register 0x00, bit1-0, DeviceStatus field.
+ * Other values indicate device is in an abnormal state and must be reset.
+ */
+#define CYAPA_DEV_NORMAL  0x03
+#define CYAPA_DEV_BUSY    0x01
+
+enum cyapa_state {
+	CYAPA_STATE_OP,
+	CYAPA_STATE_BL_IDLE,
+	CYAPA_STATE_BL_ACTIVE,
+	CYAPA_STATE_BL_BUSY,
+	CYAPA_STATE_NO_DEVICE,
+};
+
+
+struct cyapa_touch {
+	/*
+	 * high bits or x/y position value
+	 * bit 7 - 4: high 4 bits of x position value
+	 * bit 3 - 0: high 4 bits of y position value
+	 */
+	u8 xy_hi;
+	u8 x_lo;  /* low 8 bits of x position value. */
+	u8 y_lo;  /* low 8 bits of y position value. */
+	u8 pressure;
+	/* id range is 1 - 15.  It is incremented with every new touch. */
+	u8 id;
+} __packed;
+
+/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
+#define CYAPA_MAX_MT_SLOTS  15
+
+struct cyapa_reg_data {
+	/*
+	 * bit 0 - 1: device status
+	 * bit 3 - 2: power mode
+	 * bit 6 - 4: reserved
+	 * bit 7: interrupt valid bit
+	 */
+	u8 device_status;
+	/*
+	 * bit 7 - 4: number of fingers currently touching pad
+	 * bit 3: valid data check bit
+	 * bit 2: middle mechanism button state if exists
+	 * bit 1: right mechanism button state if exists
+	 * bit 0: left mechanism button state if exists
+	 */
+	u8 finger_btn;
+	/* CYAPA reports up to 5 touches per packet. */
+	struct cyapa_touch touches[5];
+} __packed;
+
+/* The main device structure */
+struct cyapa {
+	enum cyapa_state state;
+
+	struct i2c_client *client;
+	struct input_dev *input;
+	char phys[32];	/* device physical location */
+	int irq;
+	bool irq_wake;  /* irq wake is enabled */
+
+	/* read from query data region. */
+	char product_id[16];
+	u8 btn_capability;
+	u8 gen;
+	int max_abs_x;
+	int max_abs_y;
+	int physical_size_x;
+	int physical_size_y;
+};
+
+static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
+		0x04, 0x05, 0x06, 0x07 };
+static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
+		0x05, 0x06, 0x07 };
+
+struct cyapa_cmd_len {
+	u8 cmd;
+	u8 len;
+};
+
+static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
+	{CYAPA_OFFSET_SOFT_RESET, 1},
+	{REG_OFFSET_COMMAND_BASE + 1, 1},
+	{REG_OFFSET_DATA_BASE, 1},
+	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
+	{REG_OFFSET_COMMAND_BASE, 0},
+	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
+	{BL_HEAD_OFFSET, 3},
+	{BL_HEAD_OFFSET, 16},
+	{BL_HEAD_OFFSET, 16},
+	{BL_DATA_OFFSET, 16},
+	{BL_HEAD_OFFSET, 32},
+	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
+	{REG_OFFSET_DATA_BASE, 32}
+};
+
+static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
+					u8 *values)
+{
+	return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
+}
+
+static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
+					 size_t len, const u8 *values)
+{
+	return i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
+}
+
+static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+
+	return i2c_smbus_read_byte_data(cyapa->client, cmd);
+}
+
+static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+
+	return i2c_smbus_write_byte_data(cyapa->client, cmd, value);
+}
+
+static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
+{
+	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
+	size_t len = cyapa_i2c_cmds[cmd_idx].len;
+
+	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
+}
+
+/*
+ * Query device for its current operating state.
+ *
+ */
+static int cyapa_get_state(struct cyapa *cyapa)
+{
+	int ret;
+	u8 status[BL_STATUS_SIZE];
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+
+	/*
+	 * Get trackpad status by reading 3 registers starting from 0.
+	 * If the device is in the bootloader, this will be BL_HEAD.
+	 * If the device is in operation mode, this will be the DATA regs.
+	 *
+	 */
+	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
+				       status);
+	if (ret != BL_STATUS_SIZE)
+		goto error;
+
+	if ((status[REG_OP_STATUS] & OP_STATUS_SRC) == OP_STATUS_SRC) {
+		switch (status[REG_OP_STATUS] & OP_STATUS_DEV) {
+		case CYAPA_DEV_NORMAL:
+		case CYAPA_DEV_BUSY:
+			cyapa->state = CYAPA_STATE_OP;
+			break;
+		default:
+			ret = -EAGAIN;
+			goto error;
+		}
+	} else {
+		if (status[REG_BL_STATUS] & BL_STATUS_BUSY)
+			cyapa->state = CYAPA_STATE_BL_BUSY;
+		else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING)
+			cyapa->state = CYAPA_STATE_BL_ACTIVE;
+		else
+			cyapa->state = CYAPA_STATE_BL_IDLE;
+	}
+
+	return 0;
+error:
+	return (ret < 0) ? ret : -EAGAIN;
+}
+
+/*
+ * Poll device for its status in a loop, waiting up to timeout for a response.
+ *
+ * When the device switches state, it usually takes ~300 ms.
+ * However, when running a new firmware image, the device must calibrate its
+ * sensors, which can take as long as 2 seconds.
+ *
+ * Note: The timeout has granularity of the polling rate, which is 100 ms.
+ *
+ * Returns:
+ *   0 when the device eventually responds with a valid non-busy state.
+ *   -ETIMEDOUT if device never responds (too many -EAGAIN)
+ *   < 0    other errors
+ */
+static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
+{
+	int ret;
+	int tries = timeout / 100;
+
+	ret = cyapa_get_state(cyapa);
+	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
+		msleep(100);
+		ret = cyapa_get_state(cyapa);
+	}
+	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
+}
+
+static int cyapa_bl_deactivate(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
+					bl_deactivate);
+	if (ret < 0)
+		return ret;
+
+	/* wait for bootloader to switch to idle state; should take < 100ms */
+	msleep(100);
+	ret = cyapa_poll_state(cyapa, 500);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_BL_IDLE)
+		return -EAGAIN;
+	return 0;
+}
+
+/*
+ * Exit bootloader
+ *
+ * Send bl_exit command, then wait 50 - 100 ms to let device transition to
+ * operational mode.  If this is the first time the device's firmware is
+ * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
+ * the device's new state for up to 2 seconds.
+ *
+ * Returns:
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
+ *   0       device is supported and in operational mode
+ */
+static int cyapa_bl_exit(struct cyapa *cyapa)
+{
+	int ret;
+
+	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Wait for bootloader to exit, and operation mode to start.
+	 * Normally, this takes at least 50 ms.
+	 */
+	usleep_range(50000, 100000);
+	/*
+	 * In addition, when a device boots for the first time after being
+	 * updated to new firmware, it must first calibrate its sensors, which
+	 * can take up to an additional 2 seconds.
+	 */
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EAGAIN;
+
+	return 0;
+}
+
+/*
+ * Set device power mode
+ *
+ */
+static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	u8 power;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return 0;
+
+	ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
+	if (ret < 0)
+		return ret;
+
+	power = ret & ~PWR_MODE_MASK;
+	power |= power_mode & PWR_MODE_MASK;
+	ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
+	if (ret < 0)
+		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
+			power_mode, ret);
+	return ret;
+}
+
+static int cyapa_get_query_data(struct cyapa *cyapa)
+{
+	u8 query_data[QUERY_DATA_SIZE];
+	int ret;
+
+	if (cyapa->state != CYAPA_STATE_OP)
+		return -EBUSY;
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
+	if (ret < 0)
+		return ret;
+	if (ret != QUERY_DATA_SIZE)
+		return -EIO;
+
+	memcpy(&cyapa->product_id[0], &query_data[0], 5);
+	cyapa->product_id[5] = '-';
+	memcpy(&cyapa->product_id[6], &query_data[5], 6);
+	cyapa->product_id[12] = '-';
+	memcpy(&cyapa->product_id[13], &query_data[11], 2);
+	cyapa->product_id[15] = '\0';
+
+	cyapa->btn_capability = query_data[19] & CAPABILITY_BTN_MASK;
+
+	cyapa->gen = query_data[20] & 0x0f;
+
+	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
+	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
+
+	cyapa->physical_size_x =
+		((query_data[24] & 0xf0) << 4) | query_data[25];
+	cyapa->physical_size_y =
+		((query_data[24] & 0x0f) << 8) | query_data[26];
+
+	return 0;
+}
+
+/*
+ * Check if device is operational.
+ *
+ * An operational device is responding, has exited bootloader, and has
+ * firmware supported by this driver.
+ *
+ * Returns:
+ *   -EBUSY  no device or in bootloader
+ *   -EIO    failure while reading from device
+ *   -EAGAIN device is still in bootloader
+ *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
+ *   -EINVAL device is in operational mode, but not supported by this driver
+ *   0       device is supported
+ */
+static int cyapa_check_is_operational(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	static const char unique_str[] = "CYTRA";
+	int ret;
+
+	ret = cyapa_poll_state(cyapa, 2000);
+	if (ret < 0)
+		return ret;
+	switch (cyapa->state) {
+	case CYAPA_STATE_BL_ACTIVE:
+		ret = cyapa_bl_deactivate(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_BL_IDLE:
+		ret = cyapa_bl_exit(cyapa);
+		if (ret)
+			return ret;
+
+	/* Fallthrough state */
+	case CYAPA_STATE_OP:
+		ret = cyapa_get_query_data(cyapa);
+		if (ret < 0)
+			return ret;
+
+		/* only support firmware protocol gen3 */
+		if (cyapa->gen != CYAPA_GEN3) {
+			dev_err(dev, "unsupported protocol version (%d)",
+				cyapa->gen);
+			return -EINVAL;
+		}
+
+		/* only support product ID starting with CYTRA */
+		if (memcmp(cyapa->product_id, unique_str,
+			   sizeof(unique_str) - 1) != 0) {
+			dev_err(dev, "unsupported product ID (%s)\n",
+				cyapa->product_id);
+			return -EINVAL;
+		}
+		return 0;
+
+	default:
+		return -EIO;
+	}
+	return 0;
+}
+
+static irqreturn_t cyapa_irq(int irq, void *dev_id)
+{
+	struct cyapa *cyapa = dev_id;
+	struct device *dev = &cyapa->client->dev;
+	struct input_dev *input = cyapa->input;
+	struct cyapa_reg_data data;
+	int i;
+	int ret;
+	int num_fingers;
+
+	if (device_may_wakeup(dev))
+		pm_wakeup_event(dev, 0);
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
+	if (ret != sizeof(data))
+		goto irqhandled;
+
+	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
+	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
+	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
+		goto irqhandled;
+	}
+
+	num_fingers = (data.finger_btn >> 4) & 0x0f;
+	for (i = 0; i < num_fingers; i++) {
+		const struct cyapa_touch *touch = &data.touches[i];
+		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
+		int slot = touch->id - 1;
+
+		input_mt_slot(input, slot);
+		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+		input_report_abs(input, ABS_MT_POSITION_X,
+				 ((touch->xy_hi & 0xf0) << 4) | touch->x_lo);
+		input_report_abs(input, ABS_MT_POSITION_Y,
+				 ((touch->xy_hi & 0x0f) << 8) | touch->y_lo);
+		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
+	}
+
+	input_mt_sync_frame(input);
+
+	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
+		input_report_key(input, BTN_LEFT,
+				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
+	}
+	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK) {
+		input_report_key(input, BTN_MIDDLE,
+				 !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
+	}
+	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK) {
+		input_report_key(input, BTN_RIGHT,
+				 !!(data.finger_btn & OP_DATA_RIGHT_BTN));
+	}
+	input_sync(input);
+
+irqhandled:
+	return IRQ_HANDLED;
+}
+
+static int cyapa_create_input_dev(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	int ret;
+	struct input_dev *input;
+
+	if (!cyapa->physical_size_x || !cyapa->physical_size_y)
+		return -EINVAL;
+
+	input = cyapa->input = input_allocate_device();
+	if (!input) {
+		dev_err(dev, "allocate memory for input device failed\n");
+		return -ENOMEM;
+	}
+
+	input->name = CYAPA_NAME;
+	input->phys = cyapa->phys;
+	input->id.bustype = BUS_I2C;
+	input->id.version = 1;
+	input->id.product = 0;  /* means any product in eventcomm. */
+	input->dev.parent = &cyapa->client->dev;
+
+	input_set_drvdata(input, cyapa);
+
+	__set_bit(EV_ABS, input->evbit);
+
+	/* finger position */
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
+			     0);
+	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
+
+	input_abs_set_res(input, ABS_MT_POSITION_X,
+			  cyapa->max_abs_x / cyapa->physical_size_x);
+	input_abs_set_res(input, ABS_MT_POSITION_Y,
+			  cyapa->max_abs_y / cyapa->physical_size_y);
+
+	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
+		__set_bit(BTN_LEFT, input->keybit);
+	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
+		__set_bit(BTN_MIDDLE, input->keybit);
+	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
+		__set_bit(BTN_RIGHT, input->keybit);
+	if (cyapa->btn_capability == CAPABILITY_LEFT_BTN_MASK)
+		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
+
+	/* handle pointer emulation and unused slots in core */
+	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
+				  INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
+	if (ret) {
+		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
+		goto err_free_device;
+	}
+
+	/* Register the device in input subsystem */
+	ret = input_register_device(input);
+	if (ret) {
+		dev_err(dev, "input device register failed, %d\n", ret);
+		goto err_free_device;
+	}
+	return 0;
+
+err_free_device:
+	input_free_device(input);
+	cyapa->input = NULL;
+	return ret;
+}
+
+static int cyapa_probe(struct i2c_client *client,
+		       const struct i2c_device_id *dev_id)
+{
+	int ret;
+	struct cyapa *cyapa;
+	struct device *dev = &client->dev;
+
+	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
+	if (!cyapa) {
+		dev_err(dev, "allocate memory for cyapa failed\n");
+		return -ENOMEM;
+	}
+
+	cyapa->gen = CYAPA_GEN3;
+	cyapa->client = client;
+	i2c_set_clientdata(client, cyapa);
+	sprintf(cyapa->phys, "i2c-%d-%04x/input0", client->adapter->nr,
+		client->addr);
+
+	cyapa->state = CYAPA_STATE_NO_DEVICE;
+	ret = cyapa_check_is_operational(cyapa);
+	if (ret) {
+		dev_err(dev, "device not operational, %d\n", ret);
+		goto err_mem_free;
+	}
+
+	ret = cyapa_create_input_dev(cyapa);
+	if (ret) {
+		dev_err(dev, "create input_dev instance failed, %d\n", ret);
+		goto err_mem_free;
+	}
+
+	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+	if (ret) {
+		dev_err(dev, "set active power failed, %d\n", ret);
+		goto err_unregister_device;
+	}
+
+	cyapa->irq = client->irq;
+	ret = request_threaded_irq(cyapa->irq,
+				   NULL,
+				   cyapa_irq,
+				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				   "cyapa",
+				   cyapa);
+	if (ret) {
+		dev_err(dev, "IRQ request failed: %d\n, ", ret);
+		goto err_unregister_device;
+	}
+
+	return 0;
+
+err_unregister_device:
+	input_unregister_device(cyapa->input);
+err_mem_free:
+	kfree(cyapa);
+
+	return ret;
+}
+
+static int cyapa_remove(struct i2c_client *client)
+{
+	struct cyapa *cyapa = i2c_get_clientdata(client);
+
+	free_irq(cyapa->irq, cyapa);
+	input_unregister_device(cyapa->input);
+	cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
+	kfree(cyapa);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cyapa_suspend(struct device *dev)
+{
+	int ret;
+	u8 power_mode;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	disable_irq(cyapa->irq);
+
+	/*
+	 * Set trackpad device to idle mode if wakeup is allowed,
+	 * otherwise turn off.
+	 */
+	power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
+					    : PWR_MODE_OFF;
+	ret = cyapa_set_power_mode(cyapa, power_mode);
+	if (ret < 0)
+		dev_err(dev, "set power mode failed, %d\n", ret);
+
+	if (device_may_wakeup(dev))
+		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
+	return 0;
+}
+
+static int cyapa_resume(struct device *dev)
+{
+	int ret;
+	struct cyapa *cyapa = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev) && cyapa->irq_wake)
+		disable_irq_wake(cyapa->irq);
+
+	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
+	if (ret)
+		dev_warn(dev, "resume active power failed, %d\n", ret);
+
+	enable_irq(cyapa->irq);
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
+
+static const struct i2c_device_id cyapa_id_table[] = {
+	{ "cyapa", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
+
+static struct i2c_driver cyapa_driver = {
+	.driver = {
+		.name = "cyapa",
+		.owner = THIS_MODULE,
+		.pm = &cyapa_pm_ops,
+	},
+
+	.probe = cyapa_probe,
+	.remove = cyapa_remove,
+	.id_table = cyapa_id_table,
+};
+
+module_i2c_driver(cyapa_driver);
+
+MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
+MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
+MODULE_LICENSE("GPL");
-- 
1.7.7.3


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH v2 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-07 22:52       ` Benson Leung
@ 2012-12-08 12:39         ` Henrik Rydberg
  0 siblings, 0 replies; 14+ messages in thread
From: Henrik Rydberg @ 2012-12-08 12:39 UTC (permalink / raw)
  To: Benson Leung
  Cc: Dmitry Torokhov, linux-input, linux-kernel, Daniel Kurtz,
	Olof Johansson, Dudley Du

Hi Benson,

> I have applied your patch, but I found I still need this line in my
> driver, otherwise, there are no ABS type event supported. Should the
> core set this bit as well since it's certainly going to be dealing
> with ABS data?
> 
> __set_bit(EV_ABS, input->evbit);

Yes, that would make sense, I will look into it.

> Otherwise, it works great on my Chromebook trackpad here.

Great,
Henrik

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v3 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-07 23:24     ` [PATCH v3 1/1] " Benson Leung
@ 2012-12-08 12:42       ` Henrik Rydberg
  2012-12-13 22:46         ` Benson Leung
  2013-01-22 17:57       ` [v3,1/1] " Doug Anderson
  1 sibling, 1 reply; 14+ messages in thread
From: Henrik Rydberg @ 2012-12-08 12:42 UTC (permalink / raw)
  To: Benson Leung
  Cc: khali, dmitry.torokhov, linux-input, linux-kernel, djkurtz, olofj, dudl

On Fri, Dec 07, 2012 at 03:24:16PM -0800, Benson Leung wrote:
> This patch introduces a driver for Cypress All Points Addressable
> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
> 
> This device is compatible with MT protocol type B, providing identifiable
> contacts.
> 
> Signed-off-by: Dudley Du <dudl@cypress.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Benson Leung <bleung@chromium.org>
> ---
> Version history :
> v3 : * Handle pointer emulation and unused slots in core
>      * Fix compile fail on 3.7 for input_mt_init_slots (Thanks Rydberg)
>      * Set BUTTONPAD property only if is a buttonpad based on capabilities.
>      * Removed __devinit/__devexit/__devexit_p
>      * Set to OFF power mode on cyapa_remove
>      * Got rid of kasprintf'd physical location string for static one.
> 
> v2 : * Removed firmware update.
>      * Removed sysfs properties related to firmware update and power mode.
>      * Folded cyapa_detect into cyapa_probe.
>      * Added support for middle and right mechanical buttons, if they exist.
>      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
>          a power mode change from colliding with a read of tracking data.
>      * Made cyapa_get_state more reliable.
>      * Use IRQF_ONESHOT for threaded irq
>      * Simplified cyapa_set_power_mode.
>      * Removed extra kernel-doc style comments
>      * Removed dev_dbg messages.
>      * Cleaned up unused includes.
>      * Cleaned up unused #defines
> 
> v1 : Initial
> ---
>  drivers/input/mouse/Kconfig  |   12 +
>  drivers/input/mouse/Makefile |    1 +
>  drivers/input/mouse/cyapa.c  |  803 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 816 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/input/mouse/cyapa.c
> 
> diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
> index cd6268c..23db30a 100644
> --- a/drivers/input/mouse/Kconfig
> +++ b/drivers/input/mouse/Kconfig
> @@ -193,6 +193,18 @@ config MOUSE_BCM5974
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called bcm5974.
>  
> +config MOUSE_CYAPA
> +	tristate "Cypress APA I2C Trackpad support"
> +	depends on I2C
> +	help
> +	  This driver adds support for Cypress All Points Addressable (APA)
> +	  I2C Trackpads, including the ones used in 2012 Samsung Chromebooks.
> +
> +	  Say Y here if you have a Cypress APA I2C Trackpad.
> +
> +	  To compile this driver as a module, choose M here: the module will be
> +	  called cyapa.
> +
>  config MOUSE_INPORT
>  	tristate "InPort/MS/ATIXL busmouse"
>  	depends on ISA
> diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
> index 46ba755..10b4773 100644
> --- a/drivers/input/mouse/Makefile
> +++ b/drivers/input/mouse/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)		+= amimouse.o
>  obj-$(CONFIG_MOUSE_APPLETOUCH)		+= appletouch.o
>  obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
>  obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
> +obj-$(CONFIG_MOUSE_CYAPA)		+= cyapa.o
>  obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
>  obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
>  obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
> diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
> new file mode 100644
> index 0000000..0964583
> --- /dev/null
> +++ b/drivers/input/mouse/cyapa.c
> @@ -0,0 +1,803 @@
> +/*
> + * Cypress APA trackpad with I2C interface
> + *
> + * Author: Dudley Du <dudl@cypress.com>
> + * Further cleanup and restructuring by:
> + *   Daniel Kurtz <djkurtz@chromium.org>
> + *   Benson Leung <bleung@chromium.org>
> + *
> + * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
> + * Copyright (C) 2011-2012 Google, Inc.
> + *
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License.  See the file COPYING in the main directory of this archive for
> + * more details.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/input/mt.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +
> +/* APA trackpad firmware generation */
> +#define CYAPA_GEN3   0x03   /* support MT-protocol B with tracking ID. */
> +
> +#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
> +
> +/* commands for read/write registers of Cypress trackpad */
> +#define CYAPA_CMD_SOFT_RESET       0x00
> +#define CYAPA_CMD_POWER_MODE       0x01
> +#define CYAPA_CMD_DEV_STATUS       0x02
> +#define CYAPA_CMD_GROUP_DATA       0x03
> +#define CYAPA_CMD_GROUP_CMD        0x04
> +#define CYAPA_CMD_GROUP_QUERY      0x05
> +#define CYAPA_CMD_BL_STATUS        0x06
> +#define CYAPA_CMD_BL_HEAD          0x07
> +#define CYAPA_CMD_BL_CMD           0x08
> +#define CYAPA_CMD_BL_DATA          0x09
> +#define CYAPA_CMD_BL_ALL           0x0a
> +#define CYAPA_CMD_BLK_PRODUCT_ID   0x0b
> +#define CYAPA_CMD_BLK_HEAD         0x0c
> +
> +/* report data start reg offset address. */
> +#define DATA_REG_START_OFFSET  0x0000
> +
> +#define BL_HEAD_OFFSET 0x00
> +#define BL_DATA_OFFSET 0x10
> +
> +/*
> + * Operational Device Status Register
> + *
> + * bit 7: Valid interrupt source
> + * bit 6 - 4: Reserved
> + * bit 3 - 2: Power status
> + * bit 1 - 0: Device status
> + */
> +#define REG_OP_STATUS     0x00
> +#define OP_STATUS_SRC     0x80
> +#define OP_STATUS_POWER   0x0c
> +#define OP_STATUS_DEV     0x03
> +#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
> +
> +/*
> + * Operational Finger Count/Button Flags Register
> + *
> + * bit 7 - 4: Number of touched finger
> + * bit 3: Valid data
> + * bit 2: Middle Physical Button
> + * bit 1: Right Physical Button
> + * bit 0: Left physical Button
> + */
> +#define REG_OP_DATA1       0x01
> +#define OP_DATA_VALID      0x08
> +#define OP_DATA_MIDDLE_BTN 0x04
> +#define OP_DATA_RIGHT_BTN  0x02
> +#define OP_DATA_LEFT_BTN   0x01
> +#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
> +			  OP_DATA_LEFT_BTN)
> +
> +/*
> + * Bootloader Status Register
> + *
> + * bit 7: Busy
> + * bit 6 - 5: Reserved
> + * bit 4: Bootloader running
> + * bit 3 - 1: Reserved
> + * bit 0: Checksum valid
> + */
> +#define REG_BL_STATUS        0x01
> +#define BL_STATUS_BUSY       0x80
> +#define BL_STATUS_RUNNING    0x10
> +#define BL_STATUS_DATA_VALID 0x08
> +#define BL_STATUS_CSUM_VALID 0x01
> +
> +/*
> + * Bootloader Error Register
> + *
> + * bit 7: Invalid
> + * bit 6: Invalid security key
> + * bit 5: Bootloading
> + * bit 4: Command checksum
> + * bit 3: Flash protection error
> + * bit 2: Flash checksum error
> + * bit 1 - 0: Reserved
> + */
> +#define REG_BL_ERROR         0x02
> +#define BL_ERROR_INVALID     0x80
> +#define BL_ERROR_INVALID_KEY 0x40
> +#define BL_ERROR_BOOTLOADING 0x20
> +#define BL_ERROR_CMD_CSUM    0x10
> +#define BL_ERROR_FLASH_PROT  0x08
> +#define BL_ERROR_FLASH_CSUM  0x04
> +
> +#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
> +#define BLK_HEAD_BYTES 32
> +
> +#define PRODUCT_ID_SIZE  16
> +#define QUERY_DATA_SIZE  27
> +#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
> +
> +#define REG_OFFSET_DATA_BASE     0x0000
> +#define REG_OFFSET_COMMAND_BASE  0x0028
> +#define REG_OFFSET_QUERY_BASE    0x002a
> +
> +#define CAPABILITY_LEFT_BTN_MASK	(0x01 << 3)
> +#define CAPABILITY_RIGHT_BTN_MASK	(0x01 << 4)
> +#define CAPABILITY_MIDDLE_BTN_MASK	(0x01 << 5)
> +#define CAPABILITY_BTN_MASK  (CAPABILITY_LEFT_BTN_MASK | \
> +			      CAPABILITY_RIGHT_BTN_MASK | \
> +			      CAPABILITY_MIDDLE_BTN_MASK)
> +
> +#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
> +
> +#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
> +
> +#define PWR_MODE_MASK   0xfc
> +#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
> +#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
> +#define PWR_MODE_OFF         (0x00 << 2)
> +
> +#define PWR_STATUS_MASK      0x0c
> +#define PWR_STATUS_ACTIVE    (0x03 << 2)
> +#define PWR_STATUS_IDLE      (0x02 << 2)
> +#define PWR_STATUS_OFF       (0x00 << 2)
> +
> +/*
> + * CYAPA trackpad device states.
> + * Used in register 0x00, bit1-0, DeviceStatus field.
> + * Other values indicate device is in an abnormal state and must be reset.
> + */
> +#define CYAPA_DEV_NORMAL  0x03
> +#define CYAPA_DEV_BUSY    0x01
> +
> +enum cyapa_state {
> +	CYAPA_STATE_OP,
> +	CYAPA_STATE_BL_IDLE,
> +	CYAPA_STATE_BL_ACTIVE,
> +	CYAPA_STATE_BL_BUSY,
> +	CYAPA_STATE_NO_DEVICE,
> +};
> +
> +
> +struct cyapa_touch {
> +	/*
> +	 * high bits or x/y position value
> +	 * bit 7 - 4: high 4 bits of x position value
> +	 * bit 3 - 0: high 4 bits of y position value
> +	 */
> +	u8 xy_hi;
> +	u8 x_lo;  /* low 8 bits of x position value. */
> +	u8 y_lo;  /* low 8 bits of y position value. */
> +	u8 pressure;
> +	/* id range is 1 - 15.  It is incremented with every new touch. */
> +	u8 id;
> +} __packed;
> +
> +/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
> +#define CYAPA_MAX_MT_SLOTS  15
> +
> +struct cyapa_reg_data {
> +	/*
> +	 * bit 0 - 1: device status
> +	 * bit 3 - 2: power mode
> +	 * bit 6 - 4: reserved
> +	 * bit 7: interrupt valid bit
> +	 */
> +	u8 device_status;
> +	/*
> +	 * bit 7 - 4: number of fingers currently touching pad
> +	 * bit 3: valid data check bit
> +	 * bit 2: middle mechanism button state if exists
> +	 * bit 1: right mechanism button state if exists
> +	 * bit 0: left mechanism button state if exists
> +	 */
> +	u8 finger_btn;
> +	/* CYAPA reports up to 5 touches per packet. */
> +	struct cyapa_touch touches[5];
> +} __packed;
> +
> +/* The main device structure */
> +struct cyapa {
> +	enum cyapa_state state;
> +
> +	struct i2c_client *client;
> +	struct input_dev *input;
> +	char phys[32];	/* device physical location */
> +	int irq;
> +	bool irq_wake;  /* irq wake is enabled */
> +
> +	/* read from query data region. */
> +	char product_id[16];
> +	u8 btn_capability;
> +	u8 gen;
> +	int max_abs_x;
> +	int max_abs_y;
> +	int physical_size_x;
> +	int physical_size_y;
> +};
> +
> +static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
> +		0x04, 0x05, 0x06, 0x07 };
> +static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
> +		0x05, 0x06, 0x07 };
> +
> +struct cyapa_cmd_len {
> +	u8 cmd;
> +	u8 len;
> +};
> +
> +static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
> +	{CYAPA_OFFSET_SOFT_RESET, 1},
> +	{REG_OFFSET_COMMAND_BASE + 1, 1},
> +	{REG_OFFSET_DATA_BASE, 1},
> +	{REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
> +	{REG_OFFSET_COMMAND_BASE, 0},
> +	{REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
> +	{BL_HEAD_OFFSET, 3},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 16},
> +	{BL_DATA_OFFSET, 16},
> +	{BL_HEAD_OFFSET, 32},
> +	{REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
> +	{REG_OFFSET_DATA_BASE, 32}
> +};
> +
> +static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
> +					u8 *values)
> +{
> +	return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
> +}
> +
> +static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
> +					 size_t len, const u8 *values)
> +{
> +	return i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
> +}
> +
> +static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +
> +	return i2c_smbus_read_byte_data(cyapa->client, cmd);
> +}
> +
> +static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +
> +	return i2c_smbus_write_byte_data(cyapa->client, cmd, value);
> +}
> +
> +static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
> +{
> +	u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
> +	size_t len = cyapa_i2c_cmds[cmd_idx].len;
> +
> +	return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
> +}
> +
> +/*
> + * Query device for its current operating state.
> + *
> + */
> +static int cyapa_get_state(struct cyapa *cyapa)
> +{
> +	int ret;
> +	u8 status[BL_STATUS_SIZE];
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +
> +	/*
> +	 * Get trackpad status by reading 3 registers starting from 0.
> +	 * If the device is in the bootloader, this will be BL_HEAD.
> +	 * If the device is in operation mode, this will be the DATA regs.
> +	 *
> +	 */
> +	ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
> +				       status);
> +	if (ret != BL_STATUS_SIZE)
> +		goto error;
> +
> +	if ((status[REG_OP_STATUS] & OP_STATUS_SRC) == OP_STATUS_SRC) {
> +		switch (status[REG_OP_STATUS] & OP_STATUS_DEV) {
> +		case CYAPA_DEV_NORMAL:
> +		case CYAPA_DEV_BUSY:
> +			cyapa->state = CYAPA_STATE_OP;
> +			break;
> +		default:
> +			ret = -EAGAIN;
> +			goto error;
> +		}
> +	} else {
> +		if (status[REG_BL_STATUS] & BL_STATUS_BUSY)
> +			cyapa->state = CYAPA_STATE_BL_BUSY;
> +		else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING)
> +			cyapa->state = CYAPA_STATE_BL_ACTIVE;
> +		else
> +			cyapa->state = CYAPA_STATE_BL_IDLE;
> +	}
> +
> +	return 0;
> +error:
> +	return (ret < 0) ? ret : -EAGAIN;
> +}
> +
> +/*
> + * Poll device for its status in a loop, waiting up to timeout for a response.
> + *
> + * When the device switches state, it usually takes ~300 ms.
> + * However, when running a new firmware image, the device must calibrate its
> + * sensors, which can take as long as 2 seconds.
> + *
> + * Note: The timeout has granularity of the polling rate, which is 100 ms.
> + *
> + * Returns:
> + *   0 when the device eventually responds with a valid non-busy state.
> + *   -ETIMEDOUT if device never responds (too many -EAGAIN)
> + *   < 0    other errors
> + */
> +static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
> +{
> +	int ret;
> +	int tries = timeout / 100;
> +
> +	ret = cyapa_get_state(cyapa);
> +	while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
> +		msleep(100);
> +		ret = cyapa_get_state(cyapa);
> +	}
> +	return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
> +}
> +
> +static int cyapa_bl_deactivate(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
> +					bl_deactivate);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* wait for bootloader to switch to idle state; should take < 100ms */
> +	msleep(100);
> +	ret = cyapa_poll_state(cyapa, 500);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_BL_IDLE)
> +		return -EAGAIN;
> +	return 0;
> +}
> +
> +/*
> + * Exit bootloader
> + *
> + * Send bl_exit command, then wait 50 - 100 ms to let device transition to
> + * operational mode.  If this is the first time the device's firmware is
> + * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
> + * the device's new state for up to 2 seconds.
> + *
> + * Returns:
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
> + *   0       device is supported and in operational mode
> + */
> +static int cyapa_bl_exit(struct cyapa *cyapa)
> +{
> +	int ret;
> +
> +	ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * Wait for bootloader to exit, and operation mode to start.
> +	 * Normally, this takes at least 50 ms.
> +	 */
> +	usleep_range(50000, 100000);
> +	/*
> +	 * In addition, when a device boots for the first time after being
> +	 * updated to new firmware, it must first calibrate its sensors, which
> +	 * can take up to an additional 2 seconds.
> +	 */
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EAGAIN;
> +
> +	return 0;
> +}
> +
> +/*
> + * Set device power mode
> + *
> + */
> +static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	u8 power;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return 0;
> +
> +	ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
> +	if (ret < 0)
> +		return ret;
> +
> +	power = ret & ~PWR_MODE_MASK;
> +	power |= power_mode & PWR_MODE_MASK;
> +	ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
> +	if (ret < 0)
> +		dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
> +			power_mode, ret);
> +	return ret;
> +}
> +
> +static int cyapa_get_query_data(struct cyapa *cyapa)
> +{
> +	u8 query_data[QUERY_DATA_SIZE];
> +	int ret;
> +
> +	if (cyapa->state != CYAPA_STATE_OP)
> +		return -EBUSY;
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
> +	if (ret < 0)
> +		return ret;
> +	if (ret != QUERY_DATA_SIZE)
> +		return -EIO;
> +
> +	memcpy(&cyapa->product_id[0], &query_data[0], 5);
> +	cyapa->product_id[5] = '-';
> +	memcpy(&cyapa->product_id[6], &query_data[5], 6);
> +	cyapa->product_id[12] = '-';
> +	memcpy(&cyapa->product_id[13], &query_data[11], 2);
> +	cyapa->product_id[15] = '\0';
> +
> +	cyapa->btn_capability = query_data[19] & CAPABILITY_BTN_MASK;
> +
> +	cyapa->gen = query_data[20] & 0x0f;
> +
> +	cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
> +	cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
> +
> +	cyapa->physical_size_x =
> +		((query_data[24] & 0xf0) << 4) | query_data[25];
> +	cyapa->physical_size_y =
> +		((query_data[24] & 0x0f) << 8) | query_data[26];
> +
> +	return 0;
> +}
> +
> +/*
> + * Check if device is operational.
> + *
> + * An operational device is responding, has exited bootloader, and has
> + * firmware supported by this driver.
> + *
> + * Returns:
> + *   -EBUSY  no device or in bootloader
> + *   -EIO    failure while reading from device
> + *   -EAGAIN device is still in bootloader
> + *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
> + *   -EINVAL device is in operational mode, but not supported by this driver
> + *   0       device is supported
> + */
> +static int cyapa_check_is_operational(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	static const char unique_str[] = "CYTRA";
> +	int ret;
> +
> +	ret = cyapa_poll_state(cyapa, 2000);
> +	if (ret < 0)
> +		return ret;
> +	switch (cyapa->state) {
> +	case CYAPA_STATE_BL_ACTIVE:
> +		ret = cyapa_bl_deactivate(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_BL_IDLE:
> +		ret = cyapa_bl_exit(cyapa);
> +		if (ret)
> +			return ret;
> +
> +	/* Fallthrough state */
> +	case CYAPA_STATE_OP:
> +		ret = cyapa_get_query_data(cyapa);
> +		if (ret < 0)
> +			return ret;
> +
> +		/* only support firmware protocol gen3 */
> +		if (cyapa->gen != CYAPA_GEN3) {
> +			dev_err(dev, "unsupported protocol version (%d)",
> +				cyapa->gen);
> +			return -EINVAL;
> +		}
> +
> +		/* only support product ID starting with CYTRA */
> +		if (memcmp(cyapa->product_id, unique_str,
> +			   sizeof(unique_str) - 1) != 0) {
> +			dev_err(dev, "unsupported product ID (%s)\n",
> +				cyapa->product_id);
> +			return -EINVAL;
> +		}
> +		return 0;
> +
> +	default:
> +		return -EIO;
> +	}
> +	return 0;
> +}
> +
> +static irqreturn_t cyapa_irq(int irq, void *dev_id)
> +{
> +	struct cyapa *cyapa = dev_id;
> +	struct device *dev = &cyapa->client->dev;
> +	struct input_dev *input = cyapa->input;
> +	struct cyapa_reg_data data;
> +	int i;
> +	int ret;
> +	int num_fingers;
> +
> +	if (device_may_wakeup(dev))
> +		pm_wakeup_event(dev, 0);
> +
> +	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
> +	if (ret != sizeof(data))
> +		goto irqhandled;
> +
> +	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
> +	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
> +	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
> +		goto irqhandled;
> +	}
> +
> +	num_fingers = (data.finger_btn >> 4) & 0x0f;
> +	for (i = 0; i < num_fingers; i++) {
> +		const struct cyapa_touch *touch = &data.touches[i];
> +		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
> +		int slot = touch->id - 1;
> +
> +		input_mt_slot(input, slot);
> +		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
> +		input_report_abs(input, ABS_MT_POSITION_X,
> +				 ((touch->xy_hi & 0xf0) << 4) | touch->x_lo);
> +		input_report_abs(input, ABS_MT_POSITION_Y,
> +				 ((touch->xy_hi & 0x0f) << 8) | touch->y_lo);
> +		input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
> +	}
> +
> +	input_mt_sync_frame(input);
> +
> +	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
> +		input_report_key(input, BTN_LEFT,
> +				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
> +	}
> +	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK) {
> +		input_report_key(input, BTN_MIDDLE,
> +				 !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
> +	}
> +	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK) {
> +		input_report_key(input, BTN_RIGHT,
> +				 !!(data.finger_btn & OP_DATA_RIGHT_BTN));
> +	}
> +	input_sync(input);
> +
> +irqhandled:
> +	return IRQ_HANDLED;
> +}
> +
> +static int cyapa_create_input_dev(struct cyapa *cyapa)
> +{
> +	struct device *dev = &cyapa->client->dev;
> +	int ret;
> +	struct input_dev *input;
> +
> +	if (!cyapa->physical_size_x || !cyapa->physical_size_y)
> +		return -EINVAL;
> +
> +	input = cyapa->input = input_allocate_device();
> +	if (!input) {
> +		dev_err(dev, "allocate memory for input device failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = CYAPA_NAME;
> +	input->phys = cyapa->phys;
> +	input->id.bustype = BUS_I2C;
> +	input->id.version = 1;
> +	input->id.product = 0;  /* means any product in eventcomm. */
> +	input->dev.parent = &cyapa->client->dev;
> +
> +	input_set_drvdata(input, cyapa);
> +
> +	__set_bit(EV_ABS, input->evbit);
> +
> +	/* finger position */
> +	input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
> +			     0);
> +	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
> +
> +	input_abs_set_res(input, ABS_MT_POSITION_X,
> +			  cyapa->max_abs_x / cyapa->physical_size_x);
> +	input_abs_set_res(input, ABS_MT_POSITION_Y,
> +			  cyapa->max_abs_y / cyapa->physical_size_y);
> +
> +	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
> +		__set_bit(BTN_LEFT, input->keybit);
> +	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
> +		__set_bit(BTN_MIDDLE, input->keybit);
> +	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
> +		__set_bit(BTN_RIGHT, input->keybit);
> +	if (cyapa->btn_capability == CAPABILITY_LEFT_BTN_MASK)
> +		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
> +
> +	/* handle pointer emulation and unused slots in core */
> +	ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
> +				  INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
> +	if (ret) {
> +		dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +
> +	/* Register the device in input subsystem */
> +	ret = input_register_device(input);
> +	if (ret) {
> +		dev_err(dev, "input device register failed, %d\n", ret);
> +		goto err_free_device;
> +	}
> +	return 0;
> +
> +err_free_device:
> +	input_free_device(input);
> +	cyapa->input = NULL;
> +	return ret;
> +}
> +
> +static int cyapa_probe(struct i2c_client *client,
> +		       const struct i2c_device_id *dev_id)
> +{
> +	int ret;
> +	struct cyapa *cyapa;
> +	struct device *dev = &client->dev;
> +
> +	cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
> +	if (!cyapa) {
> +		dev_err(dev, "allocate memory for cyapa failed\n");
> +		return -ENOMEM;
> +	}
> +
> +	cyapa->gen = CYAPA_GEN3;
> +	cyapa->client = client;
> +	i2c_set_clientdata(client, cyapa);
> +	sprintf(cyapa->phys, "i2c-%d-%04x/input0", client->adapter->nr,
> +		client->addr);
> +
> +	cyapa->state = CYAPA_STATE_NO_DEVICE;
> +	ret = cyapa_check_is_operational(cyapa);
> +	if (ret) {
> +		dev_err(dev, "device not operational, %d\n", ret);
> +		goto err_mem_free;
> +	}
> +
> +	ret = cyapa_create_input_dev(cyapa);
> +	if (ret) {
> +		dev_err(dev, "create input_dev instance failed, %d\n", ret);
> +		goto err_mem_free;
> +	}
> +
> +	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +	if (ret) {
> +		dev_err(dev, "set active power failed, %d\n", ret);
> +		goto err_unregister_device;
> +	}
> +
> +	cyapa->irq = client->irq;
> +	ret = request_threaded_irq(cyapa->irq,
> +				   NULL,
> +				   cyapa_irq,
> +				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +				   "cyapa",
> +				   cyapa);
> +	if (ret) {
> +		dev_err(dev, "IRQ request failed: %d\n, ", ret);
> +		goto err_unregister_device;
> +	}
> +
> +	return 0;
> +
> +err_unregister_device:
> +	input_unregister_device(cyapa->input);
> +err_mem_free:
> +	kfree(cyapa);
> +
> +	return ret;
> +}
> +
> +static int cyapa_remove(struct i2c_client *client)
> +{
> +	struct cyapa *cyapa = i2c_get_clientdata(client);
> +
> +	free_irq(cyapa->irq, cyapa);
> +	input_unregister_device(cyapa->input);
> +	cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
> +	kfree(cyapa);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int cyapa_suspend(struct device *dev)
> +{
> +	int ret;
> +	u8 power_mode;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	disable_irq(cyapa->irq);
> +
> +	/*
> +	 * Set trackpad device to idle mode if wakeup is allowed,
> +	 * otherwise turn off.
> +	 */
> +	power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
> +					    : PWR_MODE_OFF;
> +	ret = cyapa_set_power_mode(cyapa, power_mode);
> +	if (ret < 0)
> +		dev_err(dev, "set power mode failed, %d\n", ret);
> +
> +	if (device_may_wakeup(dev))
> +		cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
> +	return 0;
> +}
> +
> +static int cyapa_resume(struct device *dev)
> +{
> +	int ret;
> +	struct cyapa *cyapa = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev) && cyapa->irq_wake)
> +		disable_irq_wake(cyapa->irq);
> +
> +	ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
> +	if (ret)
> +		dev_warn(dev, "resume active power failed, %d\n", ret);
> +
> +	enable_irq(cyapa->irq);
> +	return 0;
> +}
> +#endif /* CONFIG_PM_SLEEP */
> +
> +static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
> +
> +static const struct i2c_device_id cyapa_id_table[] = {
> +	{ "cyapa", 0 },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
> +
> +static struct i2c_driver cyapa_driver = {
> +	.driver = {
> +		.name = "cyapa",
> +		.owner = THIS_MODULE,
> +		.pm = &cyapa_pm_ops,
> +	},
> +
> +	.probe = cyapa_probe,
> +	.remove = cyapa_remove,
> +	.id_table = cyapa_id_table,
> +};
> +
> +module_i2c_driver(cyapa_driver);
> +
> +MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
> +MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
> +MODULE_LICENSE("GPL");
> -- 
> 1.7.7.3
> 

    Reviewed-by: Henrik Rydberg <rydberg@euromail.se>

Thanks,
Henrik

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v3 1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-08 12:42       ` Henrik Rydberg
@ 2012-12-13 22:46         ` Benson Leung
  0 siblings, 0 replies; 14+ messages in thread
From: Benson Leung @ 2012-12-13 22:46 UTC (permalink / raw)
  To: Henrik Rydberg
  Cc: khali, Dmitry Torokhov, linux-input, linux-kernel, Daniel Kurtz,
	Olof Johansson, Dudley Du

Thanks Henrik.

Hello Dmitry, do you have any comments on V3?

On Sat, Dec 8, 2012 at 4:42 AM, Henrik Rydberg <rydberg@euromail.se> wrote:
> On Fri, Dec 07, 2012 at 03:24:16PM -0800, Benson Leung wrote:
>> This patch introduces a driver for Cypress All Points Addressable
>> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.
>>
>> This device is compatible with MT protocol type B, providing identifiable
>> contacts.
>>
>> Signed-off-by: Dudley Du <dudl@cypress.com>
>> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
>> Signed-off-by: Benson Leung <bleung@chromium.org>
>> ---
>> Version history :
>> v3 : * Handle pointer emulation and unused slots in core
>>      * Fix compile fail on 3.7 for input_mt_init_slots (Thanks Rydberg)
>>      * Set BUTTONPAD property only if is a buttonpad based on capabilities.
>>      * Removed __devinit/__devexit/__devexit_p
>>      * Set to OFF power mode on cyapa_remove
>>      * Got rid of kasprintf'd physical location string for static one.
>>
>> v2 : * Removed firmware update.
>>      * Removed sysfs properties related to firmware update and power mode.
>>      * Folded cyapa_detect into cyapa_probe.
>>      * Added support for middle and right mechanical buttons, if they exist.
>>      * Rearranged disable_irq/enable_irq in suspend and resume to prevent
>>          a power mode change from colliding with a read of tracking data.
>>      * Made cyapa_get_state more reliable.
>>      * Use IRQF_ONESHOT for threaded irq
>>      * Simplified cyapa_set_power_mode.
>>      * Removed extra kernel-doc style comments
>>      * Removed dev_dbg messages.
>>      * Cleaned up unused includes.
>>      * Cleaned up unused #defines
>>
>> v1 : Initial
>> ---
>>  drivers/input/mouse/Kconfig  |   12 +
>>  drivers/input/mouse/Makefile |    1 +
>>  drivers/input/mouse/cyapa.c  |  803 ++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 816 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/input/mouse/cyapa.c
>>
>> diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
>> index cd6268c..23db30a 100644
>> --- a/drivers/input/mouse/Kconfig
>> +++ b/drivers/input/mouse/Kconfig
>> @@ -193,6 +193,18 @@ config MOUSE_BCM5974
>>         To compile this driver as a module, choose M here: the
>>         module will be called bcm5974.
>>
>> +config MOUSE_CYAPA
>> +     tristate "Cypress APA I2C Trackpad support"
>> +     depends on I2C
>> +     help
>> +       This driver adds support for Cypress All Points Addressable (APA)
>> +       I2C Trackpads, including the ones used in 2012 Samsung Chromebooks.
>> +
>> +       Say Y here if you have a Cypress APA I2C Trackpad.
>> +
>> +       To compile this driver as a module, choose M here: the module will be
>> +       called cyapa.
>> +
>>  config MOUSE_INPORT
>>       tristate "InPort/MS/ATIXL busmouse"
>>       depends on ISA
>> diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
>> index 46ba755..10b4773 100644
>> --- a/drivers/input/mouse/Makefile
>> +++ b/drivers/input/mouse/Makefile
>> @@ -8,6 +8,7 @@ obj-$(CONFIG_MOUSE_AMIGA)             += amimouse.o
>>  obj-$(CONFIG_MOUSE_APPLETOUCH)               += appletouch.o
>>  obj-$(CONFIG_MOUSE_ATARI)            += atarimouse.o
>>  obj-$(CONFIG_MOUSE_BCM5974)          += bcm5974.o
>> +obj-$(CONFIG_MOUSE_CYAPA)            += cyapa.o
>>  obj-$(CONFIG_MOUSE_GPIO)             += gpio_mouse.o
>>  obj-$(CONFIG_MOUSE_INPORT)           += inport.o
>>  obj-$(CONFIG_MOUSE_LOGIBM)           += logibm.o
>> diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
>> new file mode 100644
>> index 0000000..0964583
>> --- /dev/null
>> +++ b/drivers/input/mouse/cyapa.c
>> @@ -0,0 +1,803 @@
>> +/*
>> + * Cypress APA trackpad with I2C interface
>> + *
>> + * Author: Dudley Du <dudl@cypress.com>
>> + * Further cleanup and restructuring by:
>> + *   Daniel Kurtz <djkurtz@chromium.org>
>> + *   Benson Leung <bleung@chromium.org>
>> + *
>> + * Copyright (C) 2011-2012 Cypress Semiconductor, Inc.
>> + * Copyright (C) 2011-2012 Google, Inc.
>> + *
>> + * This file is subject to the terms and conditions of the GNU General Public
>> + * License.  See the file COPYING in the main directory of this archive for
>> + * more details.
>> + */
>> +
>> +#include <linux/delay.h>
>> +#include <linux/i2c.h>
>> +#include <linux/input.h>
>> +#include <linux/input/mt.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/slab.h>
>> +
>> +/* APA trackpad firmware generation */
>> +#define CYAPA_GEN3   0x03   /* support MT-protocol B with tracking ID. */
>> +
>> +#define CYAPA_NAME   "Cypress APA Trackpad (cyapa)"
>> +
>> +/* commands for read/write registers of Cypress trackpad */
>> +#define CYAPA_CMD_SOFT_RESET       0x00
>> +#define CYAPA_CMD_POWER_MODE       0x01
>> +#define CYAPA_CMD_DEV_STATUS       0x02
>> +#define CYAPA_CMD_GROUP_DATA       0x03
>> +#define CYAPA_CMD_GROUP_CMD        0x04
>> +#define CYAPA_CMD_GROUP_QUERY      0x05
>> +#define CYAPA_CMD_BL_STATUS        0x06
>> +#define CYAPA_CMD_BL_HEAD          0x07
>> +#define CYAPA_CMD_BL_CMD           0x08
>> +#define CYAPA_CMD_BL_DATA          0x09
>> +#define CYAPA_CMD_BL_ALL           0x0a
>> +#define CYAPA_CMD_BLK_PRODUCT_ID   0x0b
>> +#define CYAPA_CMD_BLK_HEAD         0x0c
>> +
>> +/* report data start reg offset address. */
>> +#define DATA_REG_START_OFFSET  0x0000
>> +
>> +#define BL_HEAD_OFFSET 0x00
>> +#define BL_DATA_OFFSET 0x10
>> +
>> +/*
>> + * Operational Device Status Register
>> + *
>> + * bit 7: Valid interrupt source
>> + * bit 6 - 4: Reserved
>> + * bit 3 - 2: Power status
>> + * bit 1 - 0: Device status
>> + */
>> +#define REG_OP_STATUS     0x00
>> +#define OP_STATUS_SRC     0x80
>> +#define OP_STATUS_POWER   0x0c
>> +#define OP_STATUS_DEV     0x03
>> +#define OP_STATUS_MASK (OP_STATUS_SRC | OP_STATUS_POWER | OP_STATUS_DEV)
>> +
>> +/*
>> + * Operational Finger Count/Button Flags Register
>> + *
>> + * bit 7 - 4: Number of touched finger
>> + * bit 3: Valid data
>> + * bit 2: Middle Physical Button
>> + * bit 1: Right Physical Button
>> + * bit 0: Left physical Button
>> + */
>> +#define REG_OP_DATA1       0x01
>> +#define OP_DATA_VALID      0x08
>> +#define OP_DATA_MIDDLE_BTN 0x04
>> +#define OP_DATA_RIGHT_BTN  0x02
>> +#define OP_DATA_LEFT_BTN   0x01
>> +#define OP_DATA_BTN_MASK (OP_DATA_MIDDLE_BTN | OP_DATA_RIGHT_BTN | \
>> +                       OP_DATA_LEFT_BTN)
>> +
>> +/*
>> + * Bootloader Status Register
>> + *
>> + * bit 7: Busy
>> + * bit 6 - 5: Reserved
>> + * bit 4: Bootloader running
>> + * bit 3 - 1: Reserved
>> + * bit 0: Checksum valid
>> + */
>> +#define REG_BL_STATUS        0x01
>> +#define BL_STATUS_BUSY       0x80
>> +#define BL_STATUS_RUNNING    0x10
>> +#define BL_STATUS_DATA_VALID 0x08
>> +#define BL_STATUS_CSUM_VALID 0x01
>> +
>> +/*
>> + * Bootloader Error Register
>> + *
>> + * bit 7: Invalid
>> + * bit 6: Invalid security key
>> + * bit 5: Bootloading
>> + * bit 4: Command checksum
>> + * bit 3: Flash protection error
>> + * bit 2: Flash checksum error
>> + * bit 1 - 0: Reserved
>> + */
>> +#define REG_BL_ERROR         0x02
>> +#define BL_ERROR_INVALID     0x80
>> +#define BL_ERROR_INVALID_KEY 0x40
>> +#define BL_ERROR_BOOTLOADING 0x20
>> +#define BL_ERROR_CMD_CSUM    0x10
>> +#define BL_ERROR_FLASH_PROT  0x08
>> +#define BL_ERROR_FLASH_CSUM  0x04
>> +
>> +#define BL_STATUS_SIZE  3  /* length of bootloader status registers */
>> +#define BLK_HEAD_BYTES 32
>> +
>> +#define PRODUCT_ID_SIZE  16
>> +#define QUERY_DATA_SIZE  27
>> +#define REG_PROTOCOL_GEN_QUERY_OFFSET  20
>> +
>> +#define REG_OFFSET_DATA_BASE     0x0000
>> +#define REG_OFFSET_COMMAND_BASE  0x0028
>> +#define REG_OFFSET_QUERY_BASE    0x002a
>> +
>> +#define CAPABILITY_LEFT_BTN_MASK     (0x01 << 3)
>> +#define CAPABILITY_RIGHT_BTN_MASK    (0x01 << 4)
>> +#define CAPABILITY_MIDDLE_BTN_MASK   (0x01 << 5)
>> +#define CAPABILITY_BTN_MASK  (CAPABILITY_LEFT_BTN_MASK | \
>> +                           CAPABILITY_RIGHT_BTN_MASK | \
>> +                           CAPABILITY_MIDDLE_BTN_MASK)
>> +
>> +#define CYAPA_OFFSET_SOFT_RESET  REG_OFFSET_COMMAND_BASE
>> +
>> +#define REG_OFFSET_POWER_MODE (REG_OFFSET_COMMAND_BASE + 1)
>> +
>> +#define PWR_MODE_MASK   0xfc
>> +#define PWR_MODE_FULL_ACTIVE (0x3f << 2)
>> +#define PWR_MODE_IDLE        (0x05 << 2) /* default sleep time is 50 ms. */
>> +#define PWR_MODE_OFF         (0x00 << 2)
>> +
>> +#define PWR_STATUS_MASK      0x0c
>> +#define PWR_STATUS_ACTIVE    (0x03 << 2)
>> +#define PWR_STATUS_IDLE      (0x02 << 2)
>> +#define PWR_STATUS_OFF       (0x00 << 2)
>> +
>> +/*
>> + * CYAPA trackpad device states.
>> + * Used in register 0x00, bit1-0, DeviceStatus field.
>> + * Other values indicate device is in an abnormal state and must be reset.
>> + */
>> +#define CYAPA_DEV_NORMAL  0x03
>> +#define CYAPA_DEV_BUSY    0x01
>> +
>> +enum cyapa_state {
>> +     CYAPA_STATE_OP,
>> +     CYAPA_STATE_BL_IDLE,
>> +     CYAPA_STATE_BL_ACTIVE,
>> +     CYAPA_STATE_BL_BUSY,
>> +     CYAPA_STATE_NO_DEVICE,
>> +};
>> +
>> +
>> +struct cyapa_touch {
>> +     /*
>> +      * high bits or x/y position value
>> +      * bit 7 - 4: high 4 bits of x position value
>> +      * bit 3 - 0: high 4 bits of y position value
>> +      */
>> +     u8 xy_hi;
>> +     u8 x_lo;  /* low 8 bits of x position value. */
>> +     u8 y_lo;  /* low 8 bits of y position value. */
>> +     u8 pressure;
>> +     /* id range is 1 - 15.  It is incremented with every new touch. */
>> +     u8 id;
>> +} __packed;
>> +
>> +/* The touch.id is used as the MT slot id, thus max MT slot is 15 */
>> +#define CYAPA_MAX_MT_SLOTS  15
>> +
>> +struct cyapa_reg_data {
>> +     /*
>> +      * bit 0 - 1: device status
>> +      * bit 3 - 2: power mode
>> +      * bit 6 - 4: reserved
>> +      * bit 7: interrupt valid bit
>> +      */
>> +     u8 device_status;
>> +     /*
>> +      * bit 7 - 4: number of fingers currently touching pad
>> +      * bit 3: valid data check bit
>> +      * bit 2: middle mechanism button state if exists
>> +      * bit 1: right mechanism button state if exists
>> +      * bit 0: left mechanism button state if exists
>> +      */
>> +     u8 finger_btn;
>> +     /* CYAPA reports up to 5 touches per packet. */
>> +     struct cyapa_touch touches[5];
>> +} __packed;
>> +
>> +/* The main device structure */
>> +struct cyapa {
>> +     enum cyapa_state state;
>> +
>> +     struct i2c_client *client;
>> +     struct input_dev *input;
>> +     char phys[32];  /* device physical location */
>> +     int irq;
>> +     bool irq_wake;  /* irq wake is enabled */
>> +
>> +     /* read from query data region. */
>> +     char product_id[16];
>> +     u8 btn_capability;
>> +     u8 gen;
>> +     int max_abs_x;
>> +     int max_abs_y;
>> +     int physical_size_x;
>> +     int physical_size_y;
>> +};
>> +
>> +static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
>> +             0x04, 0x05, 0x06, 0x07 };
>> +static const u8 bl_exit[] = { 0x00, 0xff, 0xa5, 0x00, 0x01, 0x02, 0x03, 0x04,
>> +             0x05, 0x06, 0x07 };
>> +
>> +struct cyapa_cmd_len {
>> +     u8 cmd;
>> +     u8 len;
>> +};
>> +
>> +static const struct cyapa_cmd_len cyapa_i2c_cmds[] = {
>> +     {CYAPA_OFFSET_SOFT_RESET, 1},
>> +     {REG_OFFSET_COMMAND_BASE + 1, 1},
>> +     {REG_OFFSET_DATA_BASE, 1},
>> +     {REG_OFFSET_DATA_BASE, sizeof(struct cyapa_reg_data)},
>> +     {REG_OFFSET_COMMAND_BASE, 0},
>> +     {REG_OFFSET_QUERY_BASE, QUERY_DATA_SIZE},
>> +     {BL_HEAD_OFFSET, 3},
>> +     {BL_HEAD_OFFSET, 16},
>> +     {BL_HEAD_OFFSET, 16},
>> +     {BL_DATA_OFFSET, 16},
>> +     {BL_HEAD_OFFSET, 32},
>> +     {REG_OFFSET_QUERY_BASE, PRODUCT_ID_SIZE},
>> +     {REG_OFFSET_DATA_BASE, 32}
>> +};
>> +
>> +static ssize_t cyapa_i2c_reg_read_block(struct cyapa *cyapa, u8 reg, size_t len,
>> +                                     u8 *values)
>> +{
>> +     return i2c_smbus_read_i2c_block_data(cyapa->client, reg, len, values);
>> +}
>> +
>> +static ssize_t cyapa_i2c_reg_write_block(struct cyapa *cyapa, u8 reg,
>> +                                      size_t len, const u8 *values)
>> +{
>> +     return i2c_smbus_write_i2c_block_data(cyapa->client, reg, len, values);
>> +}
>> +
>> +static s32 cyapa_read_byte(struct cyapa *cyapa, u8 cmd_idx)
>> +{
>> +     u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
>> +
>> +     return i2c_smbus_read_byte_data(cyapa->client, cmd);
>> +}
>> +
>> +static s32 cyapa_write_byte(struct cyapa *cyapa, u8 cmd_idx, u8 value)
>> +{
>> +     u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
>> +
>> +     return i2c_smbus_write_byte_data(cyapa->client, cmd, value);
>> +}
>> +
>> +static ssize_t cyapa_read_block(struct cyapa *cyapa, u8 cmd_idx, u8 *values)
>> +{
>> +     u8 cmd = cyapa_i2c_cmds[cmd_idx].cmd;
>> +     size_t len = cyapa_i2c_cmds[cmd_idx].len;
>> +
>> +     return cyapa_i2c_reg_read_block(cyapa, cmd, len, values);
>> +}
>> +
>> +/*
>> + * Query device for its current operating state.
>> + *
>> + */
>> +static int cyapa_get_state(struct cyapa *cyapa)
>> +{
>> +     int ret;
>> +     u8 status[BL_STATUS_SIZE];
>> +
>> +     cyapa->state = CYAPA_STATE_NO_DEVICE;
>> +
>> +     /*
>> +      * Get trackpad status by reading 3 registers starting from 0.
>> +      * If the device is in the bootloader, this will be BL_HEAD.
>> +      * If the device is in operation mode, this will be the DATA regs.
>> +      *
>> +      */
>> +     ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
>> +                                    status);
>> +     if (ret != BL_STATUS_SIZE)
>> +             goto error;
>> +
>> +     if ((status[REG_OP_STATUS] & OP_STATUS_SRC) == OP_STATUS_SRC) {
>> +             switch (status[REG_OP_STATUS] & OP_STATUS_DEV) {
>> +             case CYAPA_DEV_NORMAL:
>> +             case CYAPA_DEV_BUSY:
>> +                     cyapa->state = CYAPA_STATE_OP;
>> +                     break;
>> +             default:
>> +                     ret = -EAGAIN;
>> +                     goto error;
>> +             }
>> +     } else {
>> +             if (status[REG_BL_STATUS] & BL_STATUS_BUSY)
>> +                     cyapa->state = CYAPA_STATE_BL_BUSY;
>> +             else if (status[REG_BL_ERROR] & BL_ERROR_BOOTLOADING)
>> +                     cyapa->state = CYAPA_STATE_BL_ACTIVE;
>> +             else
>> +                     cyapa->state = CYAPA_STATE_BL_IDLE;
>> +     }
>> +
>> +     return 0;
>> +error:
>> +     return (ret < 0) ? ret : -EAGAIN;
>> +}
>> +
>> +/*
>> + * Poll device for its status in a loop, waiting up to timeout for a response.
>> + *
>> + * When the device switches state, it usually takes ~300 ms.
>> + * However, when running a new firmware image, the device must calibrate its
>> + * sensors, which can take as long as 2 seconds.
>> + *
>> + * Note: The timeout has granularity of the polling rate, which is 100 ms.
>> + *
>> + * Returns:
>> + *   0 when the device eventually responds with a valid non-busy state.
>> + *   -ETIMEDOUT if device never responds (too many -EAGAIN)
>> + *   < 0    other errors
>> + */
>> +static int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
>> +{
>> +     int ret;
>> +     int tries = timeout / 100;
>> +
>> +     ret = cyapa_get_state(cyapa);
>> +     while ((ret || cyapa->state >= CYAPA_STATE_BL_BUSY) && tries--) {
>> +             msleep(100);
>> +             ret = cyapa_get_state(cyapa);
>> +     }
>> +     return (ret == -EAGAIN || ret == -ETIMEDOUT) ? -ETIMEDOUT : ret;
>> +}
>> +
>> +static int cyapa_bl_deactivate(struct cyapa *cyapa)
>> +{
>> +     int ret;
>> +
>> +     ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_deactivate),
>> +                                     bl_deactivate);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     /* wait for bootloader to switch to idle state; should take < 100ms */
>> +     msleep(100);
>> +     ret = cyapa_poll_state(cyapa, 500);
>> +     if (ret < 0)
>> +             return ret;
>> +     if (cyapa->state != CYAPA_STATE_BL_IDLE)
>> +             return -EAGAIN;
>> +     return 0;
>> +}
>> +
>> +/*
>> + * Exit bootloader
>> + *
>> + * Send bl_exit command, then wait 50 - 100 ms to let device transition to
>> + * operational mode.  If this is the first time the device's firmware is
>> + * running, it can take up to 2 seconds to calibrate its sensors.  So, poll
>> + * the device's new state for up to 2 seconds.
>> + *
>> + * Returns:
>> + *   -EIO    failure while reading from device
>> + *   -EAGAIN device is stuck in bootloader, b/c it has invalid firmware
>> + *   0       device is supported and in operational mode
>> + */
>> +static int cyapa_bl_exit(struct cyapa *cyapa)
>> +{
>> +     int ret;
>> +
>> +     ret = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_exit), bl_exit);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     /*
>> +      * Wait for bootloader to exit, and operation mode to start.
>> +      * Normally, this takes at least 50 ms.
>> +      */
>> +     usleep_range(50000, 100000);
>> +     /*
>> +      * In addition, when a device boots for the first time after being
>> +      * updated to new firmware, it must first calibrate its sensors, which
>> +      * can take up to an additional 2 seconds.
>> +      */
>> +     ret = cyapa_poll_state(cyapa, 2000);
>> +     if (ret < 0)
>> +             return ret;
>> +     if (cyapa->state != CYAPA_STATE_OP)
>> +             return -EAGAIN;
>> +
>> +     return 0;
>> +}
>> +
>> +/*
>> + * Set device power mode
>> + *
>> + */
>> +static int cyapa_set_power_mode(struct cyapa *cyapa, u8 power_mode)
>> +{
>> +     struct device *dev = &cyapa->client->dev;
>> +     int ret;
>> +     u8 power;
>> +
>> +     if (cyapa->state != CYAPA_STATE_OP)
>> +             return 0;
>> +
>> +     ret = cyapa_read_byte(cyapa, CYAPA_CMD_POWER_MODE);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     power = ret & ~PWR_MODE_MASK;
>> +     power |= power_mode & PWR_MODE_MASK;
>> +     ret = cyapa_write_byte(cyapa, CYAPA_CMD_POWER_MODE, power);
>> +     if (ret < 0)
>> +             dev_err(dev, "failed to set power_mode 0x%02x err = %d\n",
>> +                     power_mode, ret);
>> +     return ret;
>> +}
>> +
>> +static int cyapa_get_query_data(struct cyapa *cyapa)
>> +{
>> +     u8 query_data[QUERY_DATA_SIZE];
>> +     int ret;
>> +
>> +     if (cyapa->state != CYAPA_STATE_OP)
>> +             return -EBUSY;
>> +
>> +     ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_QUERY, query_data);
>> +     if (ret < 0)
>> +             return ret;
>> +     if (ret != QUERY_DATA_SIZE)
>> +             return -EIO;
>> +
>> +     memcpy(&cyapa->product_id[0], &query_data[0], 5);
>> +     cyapa->product_id[5] = '-';
>> +     memcpy(&cyapa->product_id[6], &query_data[5], 6);
>> +     cyapa->product_id[12] = '-';
>> +     memcpy(&cyapa->product_id[13], &query_data[11], 2);
>> +     cyapa->product_id[15] = '\0';
>> +
>> +     cyapa->btn_capability = query_data[19] & CAPABILITY_BTN_MASK;
>> +
>> +     cyapa->gen = query_data[20] & 0x0f;
>> +
>> +     cyapa->max_abs_x = ((query_data[21] & 0xf0) << 4) | query_data[22];
>> +     cyapa->max_abs_y = ((query_data[21] & 0x0f) << 8) | query_data[23];
>> +
>> +     cyapa->physical_size_x =
>> +             ((query_data[24] & 0xf0) << 4) | query_data[25];
>> +     cyapa->physical_size_y =
>> +             ((query_data[24] & 0x0f) << 8) | query_data[26];
>> +
>> +     return 0;
>> +}
>> +
>> +/*
>> + * Check if device is operational.
>> + *
>> + * An operational device is responding, has exited bootloader, and has
>> + * firmware supported by this driver.
>> + *
>> + * Returns:
>> + *   -EBUSY  no device or in bootloader
>> + *   -EIO    failure while reading from device
>> + *   -EAGAIN device is still in bootloader
>> + *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
>> + *   -EINVAL device is in operational mode, but not supported by this driver
>> + *   0       device is supported
>> + */
>> +static int cyapa_check_is_operational(struct cyapa *cyapa)
>> +{
>> +     struct device *dev = &cyapa->client->dev;
>> +     static const char unique_str[] = "CYTRA";
>> +     int ret;
>> +
>> +     ret = cyapa_poll_state(cyapa, 2000);
>> +     if (ret < 0)
>> +             return ret;
>> +     switch (cyapa->state) {
>> +     case CYAPA_STATE_BL_ACTIVE:
>> +             ret = cyapa_bl_deactivate(cyapa);
>> +             if (ret)
>> +                     return ret;
>> +
>> +     /* Fallthrough state */
>> +     case CYAPA_STATE_BL_IDLE:
>> +             ret = cyapa_bl_exit(cyapa);
>> +             if (ret)
>> +                     return ret;
>> +
>> +     /* Fallthrough state */
>> +     case CYAPA_STATE_OP:
>> +             ret = cyapa_get_query_data(cyapa);
>> +             if (ret < 0)
>> +                     return ret;
>> +
>> +             /* only support firmware protocol gen3 */
>> +             if (cyapa->gen != CYAPA_GEN3) {
>> +                     dev_err(dev, "unsupported protocol version (%d)",
>> +                             cyapa->gen);
>> +                     return -EINVAL;
>> +             }
>> +
>> +             /* only support product ID starting with CYTRA */
>> +             if (memcmp(cyapa->product_id, unique_str,
>> +                        sizeof(unique_str) - 1) != 0) {
>> +                     dev_err(dev, "unsupported product ID (%s)\n",
>> +                             cyapa->product_id);
>> +                     return -EINVAL;
>> +             }
>> +             return 0;
>> +
>> +     default:
>> +             return -EIO;
>> +     }
>> +     return 0;
>> +}
>> +
>> +static irqreturn_t cyapa_irq(int irq, void *dev_id)
>> +{
>> +     struct cyapa *cyapa = dev_id;
>> +     struct device *dev = &cyapa->client->dev;
>> +     struct input_dev *input = cyapa->input;
>> +     struct cyapa_reg_data data;
>> +     int i;
>> +     int ret;
>> +     int num_fingers;
>> +
>> +     if (device_may_wakeup(dev))
>> +             pm_wakeup_event(dev, 0);
>> +
>> +     ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
>> +     if (ret != sizeof(data))
>> +             goto irqhandled;
>> +
>> +     if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
>> +         (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
>> +         (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
>> +             goto irqhandled;
>> +     }
>> +
>> +     num_fingers = (data.finger_btn >> 4) & 0x0f;
>> +     for (i = 0; i < num_fingers; i++) {
>> +             const struct cyapa_touch *touch = &data.touches[i];
>> +             /* Note: touch->id range is 1 to 15; slots are 0 to 14. */
>> +             int slot = touch->id - 1;
>> +
>> +             input_mt_slot(input, slot);
>> +             input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
>> +             input_report_abs(input, ABS_MT_POSITION_X,
>> +                              ((touch->xy_hi & 0xf0) << 4) | touch->x_lo);
>> +             input_report_abs(input, ABS_MT_POSITION_Y,
>> +                              ((touch->xy_hi & 0x0f) << 8) | touch->y_lo);
>> +             input_report_abs(input, ABS_MT_PRESSURE, touch->pressure);
>> +     }
>> +
>> +     input_mt_sync_frame(input);
>> +
>> +     if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK) {
>> +             input_report_key(input, BTN_LEFT,
>> +                              !!(data.finger_btn & OP_DATA_LEFT_BTN));
>> +     }
>> +     if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK) {
>> +             input_report_key(input, BTN_MIDDLE,
>> +                              !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
>> +     }
>> +     if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK) {
>> +             input_report_key(input, BTN_RIGHT,
>> +                              !!(data.finger_btn & OP_DATA_RIGHT_BTN));
>> +     }
>> +     input_sync(input);
>> +
>> +irqhandled:
>> +     return IRQ_HANDLED;
>> +}
>> +
>> +static int cyapa_create_input_dev(struct cyapa *cyapa)
>> +{
>> +     struct device *dev = &cyapa->client->dev;
>> +     int ret;
>> +     struct input_dev *input;
>> +
>> +     if (!cyapa->physical_size_x || !cyapa->physical_size_y)
>> +             return -EINVAL;
>> +
>> +     input = cyapa->input = input_allocate_device();
>> +     if (!input) {
>> +             dev_err(dev, "allocate memory for input device failed\n");
>> +             return -ENOMEM;
>> +     }
>> +
>> +     input->name = CYAPA_NAME;
>> +     input->phys = cyapa->phys;
>> +     input->id.bustype = BUS_I2C;
>> +     input->id.version = 1;
>> +     input->id.product = 0;  /* means any product in eventcomm. */
>> +     input->dev.parent = &cyapa->client->dev;
>> +
>> +     input_set_drvdata(input, cyapa);
>> +
>> +     __set_bit(EV_ABS, input->evbit);
>> +
>> +     /* finger position */
>> +     input_set_abs_params(input, ABS_MT_POSITION_X, 0, cyapa->max_abs_x, 0,
>> +                          0);
>> +     input_set_abs_params(input, ABS_MT_POSITION_Y, 0, cyapa->max_abs_y, 0,
>> +                          0);
>> +     input_set_abs_params(input, ABS_MT_PRESSURE, 0, 255, 0, 0);
>> +
>> +     input_abs_set_res(input, ABS_MT_POSITION_X,
>> +                       cyapa->max_abs_x / cyapa->physical_size_x);
>> +     input_abs_set_res(input, ABS_MT_POSITION_Y,
>> +                       cyapa->max_abs_y / cyapa->physical_size_y);
>> +
>> +     if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
>> +             __set_bit(BTN_LEFT, input->keybit);
>> +     if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
>> +             __set_bit(BTN_MIDDLE, input->keybit);
>> +     if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
>> +             __set_bit(BTN_RIGHT, input->keybit);
>> +     if (cyapa->btn_capability == CAPABILITY_LEFT_BTN_MASK)
>> +             __set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
>> +
>> +     /* handle pointer emulation and unused slots in core */
>> +     ret = input_mt_init_slots(input, CYAPA_MAX_MT_SLOTS,
>> +                               INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
>> +     if (ret) {
>> +             dev_err(dev, "allocate memory for MT slots failed, %d\n", ret);
>> +             goto err_free_device;
>> +     }
>> +
>> +     /* Register the device in input subsystem */
>> +     ret = input_register_device(input);
>> +     if (ret) {
>> +             dev_err(dev, "input device register failed, %d\n", ret);
>> +             goto err_free_device;
>> +     }
>> +     return 0;
>> +
>> +err_free_device:
>> +     input_free_device(input);
>> +     cyapa->input = NULL;
>> +     return ret;
>> +}
>> +
>> +static int cyapa_probe(struct i2c_client *client,
>> +                    const struct i2c_device_id *dev_id)
>> +{
>> +     int ret;
>> +     struct cyapa *cyapa;
>> +     struct device *dev = &client->dev;
>> +
>> +     cyapa = kzalloc(sizeof(struct cyapa), GFP_KERNEL);
>> +     if (!cyapa) {
>> +             dev_err(dev, "allocate memory for cyapa failed\n");
>> +             return -ENOMEM;
>> +     }
>> +
>> +     cyapa->gen = CYAPA_GEN3;
>> +     cyapa->client = client;
>> +     i2c_set_clientdata(client, cyapa);
>> +     sprintf(cyapa->phys, "i2c-%d-%04x/input0", client->adapter->nr,
>> +             client->addr);
>> +
>> +     cyapa->state = CYAPA_STATE_NO_DEVICE;
>> +     ret = cyapa_check_is_operational(cyapa);
>> +     if (ret) {
>> +             dev_err(dev, "device not operational, %d\n", ret);
>> +             goto err_mem_free;
>> +     }
>> +
>> +     ret = cyapa_create_input_dev(cyapa);
>> +     if (ret) {
>> +             dev_err(dev, "create input_dev instance failed, %d\n", ret);
>> +             goto err_mem_free;
>> +     }
>> +
>> +     ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
>> +     if (ret) {
>> +             dev_err(dev, "set active power failed, %d\n", ret);
>> +             goto err_unregister_device;
>> +     }
>> +
>> +     cyapa->irq = client->irq;
>> +     ret = request_threaded_irq(cyapa->irq,
>> +                                NULL,
>> +                                cyapa_irq,
>> +                                IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
>> +                                "cyapa",
>> +                                cyapa);
>> +     if (ret) {
>> +             dev_err(dev, "IRQ request failed: %d\n, ", ret);
>> +             goto err_unregister_device;
>> +     }
>> +
>> +     return 0;
>> +
>> +err_unregister_device:
>> +     input_unregister_device(cyapa->input);
>> +err_mem_free:
>> +     kfree(cyapa);
>> +
>> +     return ret;
>> +}
>> +
>> +static int cyapa_remove(struct i2c_client *client)
>> +{
>> +     struct cyapa *cyapa = i2c_get_clientdata(client);
>> +
>> +     free_irq(cyapa->irq, cyapa);
>> +     input_unregister_device(cyapa->input);
>> +     cyapa_set_power_mode(cyapa, PWR_MODE_OFF);
>> +     kfree(cyapa);
>> +
>> +     return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int cyapa_suspend(struct device *dev)
>> +{
>> +     int ret;
>> +     u8 power_mode;
>> +     struct cyapa *cyapa = dev_get_drvdata(dev);
>> +
>> +     disable_irq(cyapa->irq);
>> +
>> +     /*
>> +      * Set trackpad device to idle mode if wakeup is allowed,
>> +      * otherwise turn off.
>> +      */
>> +     power_mode = device_may_wakeup(dev) ? PWR_MODE_IDLE
>> +                                         : PWR_MODE_OFF;
>> +     ret = cyapa_set_power_mode(cyapa, power_mode);
>> +     if (ret < 0)
>> +             dev_err(dev, "set power mode failed, %d\n", ret);
>> +
>> +     if (device_may_wakeup(dev))
>> +             cyapa->irq_wake = (enable_irq_wake(cyapa->irq) == 0);
>> +     return 0;
>> +}
>> +
>> +static int cyapa_resume(struct device *dev)
>> +{
>> +     int ret;
>> +     struct cyapa *cyapa = dev_get_drvdata(dev);
>> +
>> +     if (device_may_wakeup(dev) && cyapa->irq_wake)
>> +             disable_irq_wake(cyapa->irq);
>> +
>> +     ret = cyapa_set_power_mode(cyapa, PWR_MODE_FULL_ACTIVE);
>> +     if (ret)
>> +             dev_warn(dev, "resume active power failed, %d\n", ret);
>> +
>> +     enable_irq(cyapa->irq);
>> +     return 0;
>> +}
>> +#endif /* CONFIG_PM_SLEEP */
>> +
>> +static SIMPLE_DEV_PM_OPS(cyapa_pm_ops, cyapa_suspend, cyapa_resume);
>> +
>> +static const struct i2c_device_id cyapa_id_table[] = {
>> +     { "cyapa", 0 },
>> +     { },
>> +};
>> +MODULE_DEVICE_TABLE(i2c, cyapa_id_table);
>> +
>> +static struct i2c_driver cyapa_driver = {
>> +     .driver = {
>> +             .name = "cyapa",
>> +             .owner = THIS_MODULE,
>> +             .pm = &cyapa_pm_ops,
>> +     },
>> +
>> +     .probe = cyapa_probe,
>> +     .remove = cyapa_remove,
>> +     .id_table = cyapa_id_table,
>> +};
>> +
>> +module_i2c_driver(cyapa_driver);
>> +
>> +MODULE_DESCRIPTION("Cypress APA I2C Trackpad Driver");
>> +MODULE_AUTHOR("Dudley Du <dudl@cypress.com>");
>> +MODULE_LICENSE("GPL");
>> --
>> 1.7.7.3
>>
>
>     Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
>
> Thanks,
> Henrik



-- 
Benson Leung
Software Engineer, Chrom* OS
bleung@chromium.org

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [v3,1/1] Input: add driver for Cypress APA I2C Trackpad
  2012-12-07 23:24     ` [PATCH v3 1/1] " Benson Leung
  2012-12-08 12:42       ` Henrik Rydberg
@ 2013-01-22 17:57       ` Doug Anderson
  1 sibling, 0 replies; 14+ messages in thread
From: Doug Anderson @ 2013-01-22 17:57 UTC (permalink / raw)
  To: Benson Leung
  Cc: Jean Delvare, dmitry.torokhov, rydberg, linux-input,
	linux-kernel, Daniel Kurtz, Olof Johansson, dudl

Benson,

On Fri, Dec 7, 2012 at 3:24 PM, Benson Leung <bleung@chromium.org> wrote:
> This patch introduces a driver for Cypress All Points Addressable
> I2C Trackpad, including the ones in 2012 Samsung Chromebooks.

I tried this patch out on my ARM Chromebook running a kernel based on 3.8-rc1
(it has a bunch of other local patches making their way upstream as well).

This patch worked just fine to get the trackpad working.  :)


> This device is compatible with MT protocol type B, providing identifiable
> contacts.
>
> Signed-off-by: Dudley Du <dudl@cypress.com>
> Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
> Signed-off-by: Benson Leung <bleung@chromium.org>

Tested-by: Doug Anderson <dianders@chromium.org>

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2013-01-22 17:58 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-07-10 22:29 [PATCH] Input: add driver for Cypress APA I2C Trackpad Benson Leung
2012-07-16 11:05 ` Henrik Rydberg
2012-12-06  0:48 ` [PATCH v2 0/1] " Benson Leung
2012-12-06  0:48   ` [PATCH v2 1/1] " Benson Leung
2012-12-06  7:48     ` Dmitry Torokhov
2012-12-06  8:29       ` Jean Delvare
2012-12-06 14:59     ` Henrik Rydberg
2012-12-07 22:52       ` Benson Leung
2012-12-08 12:39         ` Henrik Rydberg
2012-12-07 23:24   ` [PATCH v3 0/1] " Benson Leung
2012-12-07 23:24     ` [PATCH v3 1/1] " Benson Leung
2012-12-08 12:42       ` Henrik Rydberg
2012-12-13 22:46         ` Benson Leung
2013-01-22 17:57       ` [v3,1/1] " Doug Anderson

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