Input: Cypress TTSP device driver

Input: Cypress TTSP device driver

[Javier Martinez Canillas]

Cypress TrueTouch(tm) Standard Product controllers are found in
a wide range of embedded devices. This patchset adds support for a
variety of TTSP controllers.

The original author of the driver is Kevin McNeely <kev@cypress.com>

Since the hardware is capable of tracking identifiable contacts and the
original driver used multi-touch protocol type A (stateless), I've added
multi-touch protocol type B (stateful) support.

The driver is composed of a core driver that process the data sent by
the contacts (fingers) and two bus specific interface modules (I2C and SPI).

The patchset is composed of:

[PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support
[PATCH 2/3] Input: cyttsp - add support for Cypress TTSP touchscreen I2C bus interface
[PATCH 3/3] Input: cyttsp - add support for Cypress TTSP touchscreen SPI bus interface

[PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support

[Javier Martinez Canillas]

Cypress TrueTouch(tm) Standard Product controllers are found in
a wide range of embedded devices. This driver add support for a
variety of TTSP controllers.

The driver is composed of a core driver that process the data sent by
the contacts and a set of bus specific interface modules. This patch
adds the base core TTSP driver.

The original author of the driver is Kevin McNeely <kev@cypress.com>

Since the hardware is capable of tracking identifiable contacts and the
original driver used multi-touch protocol type A (stateless), multi-touch
protocol type B (stateful) support was added by Javier Martinez Canillas.

Signed-off-by: Javier Martinez Canillas <martinez.javier@gmail.com>
---
 drivers/input/touchscreen/Kconfig              |    2 +
 drivers/input/touchscreen/Makefile             |    1 +
 drivers/input/touchscreen/cyttsp/Kconfig       |    4 +
 drivers/input/touchscreen/cyttsp/Makefile      |    1 +
 drivers/input/touchscreen/cyttsp/cyttsp_core.c |  874 ++++++++++++++++++++++++
 drivers/input/touchscreen/cyttsp/cyttsp_core.h |   56 ++
 include/linux/input/cyttsp.h                   |   68 ++
 7 files changed, 1006 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/touchscreen/cyttsp/Kconfig
 create mode 100644 drivers/input/touchscreen/cyttsp/Makefile
 create mode 100644 drivers/input/touchscreen/cyttsp/cyttsp_core.c
 create mode 100644 drivers/input/touchscreen/cyttsp/cyttsp_core.h
 create mode 100644 include/linux/input/cyttsp.h

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index cabd9e5..6933823 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -726,4 +726,6 @@ config TOUCHSCREEN_TPS6507X
 	  To compile this driver as a module, choose M here: the
 	  module will be called tps6507x_ts.
 
+source "drivers/input/touchscreen/cyttsp/Kconfig"
+
 endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 282d6f7..945950a 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -60,3 +60,4 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE)	+= mainstone-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE)	+= zylonite-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_W90X900)	+= w90p910_ts.o
 obj-$(CONFIG_TOUCHSCREEN_TPS6507X)	+= tps6507x-ts.o
+obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)	+= cyttsp/
diff --git a/drivers/input/touchscreen/cyttsp/Kconfig b/drivers/input/touchscreen/cyttsp/Kconfig
new file mode 100644
index 0000000..7e8e0f4
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/Kconfig
@@ -0,0 +1,4 @@
+config TOUCHSCREEN_CYTTSP_CORE
+	tristate "Cypress TTSP touchscreen core"
+	help
+	  Always activated for Cypress TTSP touchscreen
diff --git a/drivers/input/touchscreen/cyttsp/Makefile b/drivers/input/touchscreen/cyttsp/Makefile
new file mode 100644
index 0000000..d1b250f
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)   += cyttsp_core.o
diff --git a/drivers/input/touchscreen/cyttsp/cyttsp_core.c b/drivers/input/touchscreen/cyttsp/cyttsp_core.c
new file mode 100644
index 0000000..b37c0b8
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/cyttsp_core.c
@@ -0,0 +1,874 @@
+/*
+ * Core Source for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) touchscreen drivers.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ * Copyright (C) 2011 Javier Martinez Canillas <martinez.javier@gmail.com>
+ *
+ * Added multi-touch protocol type B support by Javier Martinez Canillas
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
+ *
+ */
+
+#include "cyttsp_core.h"
+
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+/* Bootloader number of command keys */
+#define CY_NUM_BL_KEYS    8
+
+/* helpers */
+#define GET_NUM_TOUCHES(x)          ((x) & 0x0F)
+#define IS_LARGE_AREA(x)            (((x) & 0x10) >> 4)
+#define IS_BAD_PKT(x)               ((x) & 0x20)
+#define IS_VALID_APP(x)             ((x) & 0x01)
+#define IS_OPERATIONAL_ERR(x)       ((x) & 0x3F)
+#define GET_HSTMODE(reg)            ((reg & 0x70) >> 4)
+#define GET_BOOTLOADERMODE(reg)     ((reg & 0x10) >> 4)
+
+#define CY_REG_BASE                 0x00
+#define CY_REG_ACT_DIST             0x1E
+#define CY_REG_ACT_INTRVL           0x1D
+#define CY_REG_TCH_TMOUT            (CY_REG_ACT_INTRVL+1)
+#define CY_REG_LP_INTRVL            (CY_REG_TCH_TMOUT+1)
+#define CY_MAXZ                     255
+#define CY_DELAY_DFLT               20 /* ms */
+#define CY_DELAY_MAX                (500/CY_DELAY_DFLT) /* half second */
+#define CY_ACT_DIST_DFLT            0xF8
+#define CY_HNDSHK_BIT               0x80
+/* device mode bits */
+#define CY_OPERATE_MODE             0x00
+#define CY_SYSINFO_MODE             0x10
+/* power mode select bits */
+#define CY_SOFT_RESET_MODE          0x01 /* return to Bootloader mode */
+#define CY_DEEP_SLEEP_MODE          0x02
+#define CY_LOW_POWER_MODE           0x04
+
+/* Slots management */
+#define CY_MAX_FINGER               4
+#define CY_SLOT_UNUSED              0
+
+struct cyttsp_tch {
+	__be16 x, y;
+	u8 z;
+} __packed;
+
+/* TrueTouch Standard Product Gen3 interface definition */
+struct cyttsp_xydata {
+	u8 hst_mode;
+	u8 tt_mode;
+	u8 tt_stat;
+	struct cyttsp_tch tch1;
+	u8 touch12_id;
+	struct cyttsp_tch tch2;
+	u8 gest_cnt;
+	u8 gest_id;
+	struct cyttsp_tch tch3;
+	u8 touch34_id;
+	struct cyttsp_tch tch4;
+	u8 tt_undef[3];
+	u8 act_dist;
+	u8 tt_reserved;
+} __packed;
+
+/* TTSP System Information interface definition */
+struct cyttsp_sysinfo_data {
+	u8 hst_mode;
+	u8 mfg_cmd;
+	u8 mfg_stat;
+	u8 cid[3];
+	u8 tt_undef1;
+	u8 uid[8];
+	u8 bl_verh;
+	u8 bl_verl;
+	u8 tts_verh;
+	u8 tts_verl;
+	u8 app_idh;
+	u8 app_idl;
+	u8 app_verh;
+	u8 app_verl;
+	u8 tt_undef[5];
+	u8 scn_typ;
+	u8 act_intrvl;
+	u8 tch_tmout;
+	u8 lp_intrvl;
+};
+
+/* TTSP Bootloader Register Map interface definition */
+#define CY_BL_CHKSUM_OK 0x01
+struct cyttsp_bootloader_data {
+	u8 bl_file;
+	u8 bl_status;
+	u8 bl_error;
+	u8 blver_hi;
+	u8 blver_lo;
+	u8 bld_blver_hi;
+	u8 bld_blver_lo;
+	u8 ttspver_hi;
+	u8 ttspver_lo;
+	u8 appid_hi;
+	u8 appid_lo;
+	u8 appver_hi;
+	u8 appver_lo;
+	u8 cid_0;
+	u8 cid_1;
+	u8 cid_2;
+};
+
+struct cyttsp {
+	struct device *dev;
+	int irq;
+	struct input_dev *input;
+	char phys[32];
+	const struct bus_type *bus_type;
+	const struct cyttsp_platform_data *platform_data;
+	struct cyttsp_bus_ops *bus_ops;
+	struct cyttsp_bootloader_data bl_data;
+	struct cyttsp_sysinfo_data sysinfo_data;
+	struct completion bl_ready;
+	enum cyttsp_powerstate power_state;
+	int slot_cnt;
+	int slots[CY_MAX_FINGER];
+	int slot_status[CY_MAX_FINGER];
+};
+
+static const u8 bl_command[] = {
+	0x00,			/* file offset */
+	0xFF,			/* command */
+	0xA5,			/* exit bootloader command */
+	0, 1, 2, 3, 4, 5, 6, 7	/* default keys */
+};
+
+static int ttsp_read_block_data(struct cyttsp *ts, u8 command,
+	u8 length, void *buf)
+{
+	int retval;
+	int tries;
+
+	if (!buf || !length)
+		return -EINVAL;
+
+	for (tries = 0, retval = -1;
+		tries < CY_NUM_RETRY && (retval < 0);
+		tries++)
+		retval = ts->bus_ops->read(ts->bus_ops, command, length, buf);
+
+	return retval;
+}
+
+static int ttsp_write_block_data(struct cyttsp *ts, u8 command,
+	u8 length, void *buf)
+{
+	int retval;
+	if (!buf || !length)
+		return -EINVAL;
+
+	retval = ts->bus_ops->write(ts->bus_ops, command, length, buf);
+
+	return retval;
+}
+
+static int ttsp_tch_ext(struct cyttsp *ts, void *buf)
+{
+	int retval;
+
+	if (!buf)
+		return -EIO;
+
+	retval = ts->bus_ops->ext(ts->bus_ops, buf);
+
+	return retval;
+}
+
+static int cyttsp_load_bl_regs(struct cyttsp *ts)
+{
+	int retval;
+
+	memset(&(ts->bl_data), 0, sizeof(struct cyttsp_bootloader_data));
+
+	retval =  ttsp_read_block_data(ts, CY_REG_BASE,
+		sizeof(ts->bl_data), &(ts->bl_data));
+
+	return retval;
+}
+
+static int cyttsp_bl_app_valid(struct cyttsp *ts)
+{
+	int retval;
+
+	retval = cyttsp_load_bl_regs(ts);
+
+	if (retval < 0)
+		return -ENODEV;
+
+	if (GET_BOOTLOADERMODE(ts->bl_data.bl_status)) {
+		if (IS_VALID_APP(ts->bl_data.bl_status)) {
+			dev_dbg(ts->dev, "%s: App found; normal boot\n",
+				__func__);
+			return 0;
+		} else {
+			dev_dbg(ts->dev, "%s: NO APP; load firmware!!\n",
+				__func__);
+			return -ENODEV;
+		}
+	} else if (GET_HSTMODE(ts->bl_data.bl_file) == CY_OPERATE_MODE) {
+		if (!(IS_OPERATIONAL_ERR(ts->bl_data.bl_status))) {
+			dev_dbg(ts->dev, "%s: Operational\n",
+				__func__);
+			return 1;
+		} else {
+			dev_dbg(ts->dev, "%s: Operational failure\n",
+				__func__);
+			return -ENODEV;
+		}
+	} else {
+		dev_dbg(ts->dev, "%s: Non-Operational failure\n",
+			__func__);
+			return -ENODEV;
+	}
+
+}
+
+static int cyttsp_exit_bl_mode(struct cyttsp *ts)
+{
+	int retval;
+	int tries;
+	u8 bl_cmd[sizeof(bl_command)];
+
+	memcpy(bl_cmd, bl_command, sizeof(bl_command));
+	if (ts->platform_data->bl_keys)
+		memcpy(&bl_cmd[sizeof(bl_command) - CY_NUM_BL_KEYS],
+			ts->platform_data->bl_keys, sizeof(bl_command));
+
+	dev_dbg(ts->dev,
+		"%s: bl_cmd= "
+		"%02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X\n",
+		__func__, bl_cmd[0], bl_cmd[1], bl_cmd[2],
+		bl_cmd[3], bl_cmd[4], bl_cmd[5], bl_cmd[6],
+		bl_cmd[7], bl_cmd[8], bl_cmd[9], bl_cmd[10]);
+
+	retval = ttsp_write_block_data(ts, CY_REG_BASE,
+		sizeof(bl_cmd), (void *)bl_cmd);
+	if (retval < 0)
+		return retval;
+
+	/* wait for TTSP Device to complete switch to Operational mode */
+	tries = 0;
+	do {
+		msleep(CY_DELAY_DFLT);
+		retval = cyttsp_load_bl_regs(ts);
+	} while (!((retval == 0) &&
+		!GET_BOOTLOADERMODE(ts->bl_data.bl_status)) &&
+		(tries++ < CY_DELAY_MAX));
+
+	dev_dbg(ts->dev, "%s: check bl ready tries=%d ret=%d stat=%02X\n",
+		__func__, tries, retval, ts->bl_data.bl_status);
+
+	if (retval < 0)
+		return retval;
+	else if (GET_BOOTLOADERMODE(ts->bl_data.bl_status))
+		return -ENODEV;
+	else
+		return 0;
+}
+
+static int cyttsp_set_operational_mode(struct cyttsp *ts)
+{
+	struct cyttsp_xydata xy_data;
+	int retval;
+	int tries;
+	u8 cmd = CY_OPERATE_MODE;
+
+	retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+
+	if (retval < 0)
+		return retval;
+
+	/* wait for TTSP Device to complete switch to Operational mode */
+	tries = 0;
+	do {
+		msleep(CY_DELAY_DFLT);
+		retval = ttsp_read_block_data(ts, CY_REG_BASE,
+			sizeof(xy_data), &(xy_data));
+	} while (!((retval == 0) &&
+		(xy_data.act_dist == CY_ACT_DIST_DFLT)) &&
+		(tries++ < CY_DELAY_MAX));
+
+	dev_dbg(ts->dev, "%s: check op ready tries=%d ret=%d dist=%02X\n",
+		__func__, tries, retval, xy_data.act_dist);
+
+	return retval;
+}
+
+static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
+{
+	int retval;
+	int tries;
+	u8 cmd = CY_SYSINFO_MODE;
+
+	memset(&(ts->sysinfo_data), 0, sizeof(struct cyttsp_sysinfo_data));
+
+	/* switch to sysinfo mode */
+	retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+	if (retval < 0)
+		return retval;
+
+	/* read sysinfo registers */
+	tries = 0;
+	do {
+		msleep(CY_DELAY_DFLT);
+		retval = ttsp_read_block_data(ts, CY_REG_BASE,
+			sizeof(ts->sysinfo_data), &(ts->sysinfo_data));
+	} while (!((retval == 0) &&
+		!((ts->sysinfo_data.tts_verh == 0) &&
+		(ts->sysinfo_data.tts_verl == 0))) &&
+		(tries++ < CY_DELAY_MAX));
+
+	dev_dbg(ts->dev, "%s: check sysinfo ready tries=%d ret=%d\n",
+		__func__, tries, retval);
+
+	dev_info(ts->dev, "%s: tv=%02X%02X ai=0x%02X%02X "
+		"av=0x%02X%02X ci=0x%02X%02X%02X\n", "cyttsp",
+		ts->sysinfo_data.tts_verh, ts->sysinfo_data.tts_verl,
+		ts->sysinfo_data.app_idh, ts->sysinfo_data.app_idl,
+		ts->sysinfo_data.app_verh, ts->sysinfo_data.app_verl,
+		ts->sysinfo_data.cid[0], ts->sysinfo_data.cid[1],
+		ts->sysinfo_data.cid[2]);
+
+	return retval;
+}
+
+static int cyttsp_set_sysinfo_regs(struct cyttsp *ts)
+{
+	int retval = 0;
+
+	if (ts->platform_data->act_intrvl != CY_ACT_INTRVL_DFLT ||
+		ts->platform_data->tch_tmout != CY_TCH_TMOUT_DFLT ||
+		ts->platform_data->lp_intrvl != CY_LP_INTRVL_DFLT) {
+
+		u8 intrvl_ray[3];
+
+		intrvl_ray[0] = ts->platform_data->act_intrvl;
+		intrvl_ray[1] = ts->platform_data->tch_tmout;
+		intrvl_ray[2] = ts->platform_data->lp_intrvl;
+
+		/* set intrvl registers */
+		retval = ttsp_write_block_data(ts,
+				CY_REG_ACT_INTRVL,
+				sizeof(intrvl_ray), intrvl_ray);
+
+		msleep(CY_DELAY_DFLT);
+	}
+
+	return retval;
+}
+
+static int cyttsp_soft_reset(struct cyttsp *ts)
+{
+	int retval;
+	u8 cmd = CY_SOFT_RESET_MODE;
+
+	retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+	if (retval < 0)
+		return retval;
+
+	/* wait for interrupt to set ready completion */
+	INIT_COMPLETION(ts->bl_ready);
+
+	retval = wait_for_completion_interruptible_timeout(&ts->bl_ready,
+		msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
+
+	if (retval > 0)
+		retval = 0;
+
+	return retval;
+}
+
+static int cyttsp_act_dist_setup(struct cyttsp *ts)
+{
+	int retval;
+	u8 act_dist_setup;
+
+	/* Init gesture; active distance setup */
+	act_dist_setup = ts->platform_data->act_dist;
+	retval = ttsp_write_block_data(ts, CY_REG_ACT_DIST,
+		sizeof(act_dist_setup), &act_dist_setup);
+
+	return retval;
+}
+
+static int cyttsp_hndshk(struct cyttsp *ts, u8 hst_mode)
+{
+	int retval;
+	u8 cmd;
+
+	cmd = hst_mode & CY_HNDSHK_BIT ?
+		hst_mode & ~CY_HNDSHK_BIT :
+		hst_mode | CY_HNDSHK_BIT;
+
+	retval = ttsp_write_block_data(ts, CY_REG_BASE,
+		sizeof(cmd), (u8 *)&cmd);
+
+	return retval;
+}
+
+static void cyttsp_report_slot(struct input_dev *dev, int slot,
+			       int x, int y, int z)
+{
+	input_mt_slot(dev, slot);
+	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
+	input_report_abs(dev, ABS_MT_POSITION_X, x);
+	input_report_abs(dev, ABS_MT_POSITION_Y, y);
+	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, z);
+}
+
+static void cyttsp_report_slot_empty(struct input_dev *dev, int slot)
+{
+	input_mt_slot(dev, slot);
+	input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
+}
+
+static void cyttsp_extract_track_ids(struct cyttsp_xydata *xy_data, int *ids)
+{
+	ids[0] = xy_data->touch12_id >> 4;
+	ids[1] = xy_data->touch12_id & 0xF;
+	ids[2] = xy_data->touch34_id >> 4;
+	ids[3] = xy_data->touch34_id & 0xF;
+}
+
+static void cyttsp_get_tch(struct cyttsp_xydata *xy_data, int idx,
+			   struct cyttsp_tch **tch)
+{
+	switch (idx) {
+	case 0:
+		*tch = &xy_data->tch1;
+		break;
+	case 1:
+		*tch = &xy_data->tch2;
+		break;
+	case 2:
+		*tch = &xy_data->tch3;
+		break;
+	case 3:
+		*tch = &xy_data->tch4;
+		break;
+	}
+}
+
+static int cyttsp_get_slot_id(struct cyttsp *ts, int id)
+{
+	int i;
+
+	for (i = 0; i < CY_MAX_FINGER; i++)
+		if (ts->slots[i] == id)
+			return i;
+
+	return -1;
+}
+
+static int cyttsp_assign_next_slot(struct cyttsp *ts, int id)
+{
+	int i;
+
+	for (i = 0; i < CY_MAX_FINGER; i++)
+		if (ts->slots[i] == CY_SLOT_UNUSED) {
+			ts->slots[i] = id;
+			ts->slot_cnt++;
+			return i;
+		}
+
+	return -1;
+}
+
+static int cyttsp_xy_worker(struct cyttsp *ts)
+{
+	struct cyttsp_xydata xy_data;
+	u8 num_cur_tch;
+	int i;
+	int ids[4];
+	int slot = -1;
+	struct cyttsp_tch *tch = NULL;
+	int x, y, z;
+
+	/* Get touch data from CYTTSP device */
+	if (ttsp_read_block_data(ts,
+		CY_REG_BASE, sizeof(struct cyttsp_xydata), &xy_data))
+		return 0;
+
+	/* touch extension handling */
+	if (ttsp_tch_ext(ts, &xy_data))
+		return 0;
+
+	/* provide flow control handshake */
+	if (ts->platform_data->use_hndshk)
+		if (cyttsp_hndshk(ts, xy_data.hst_mode))
+			return 0;
+
+	/* determine number of currently active touches */
+	num_cur_tch = GET_NUM_TOUCHES(xy_data.tt_stat);
+
+	/* check for any error conditions */
+	if (ts->power_state == CY_IDLE_STATE)
+		return 0;
+	else if (GET_BOOTLOADERMODE(xy_data.tt_mode)) {
+		return -1;
+	} else if (IS_LARGE_AREA(xy_data.tt_stat) == 1) {
+		/* terminate all active tracks */
+		num_cur_tch = 0;
+		dev_dbg(ts->dev, "%s: Large area detected\n", __func__);
+	} else if (num_cur_tch > CY_MAX_FINGER) {
+		/* terminate all active tracks */
+		num_cur_tch = 0;
+		dev_dbg(ts->dev, "%s: Num touch error detected\n", __func__);
+	} else if (IS_BAD_PKT(xy_data.tt_mode)) {
+		/* terminate all active tracks */
+		num_cur_tch = 0;
+		dev_dbg(ts->dev, "%s: Invalid buffer detected\n", __func__);
+	}
+
+	cyttsp_extract_track_ids(&xy_data, ids);
+
+	for (i = 0; i < CY_MAX_FINGER; i++)
+		ts->slot_status[i] = false;
+
+	for (i = 0; i < num_cur_tch; i++) {
+		slot = cyttsp_get_slot_id(ts, ids[i]);
+
+		if (slot < 0)
+			slot = cyttsp_assign_next_slot(ts, ids[i]);
+
+		cyttsp_get_tch(&xy_data, i, &tch);
+
+		x = be16_to_cpu(tch->x);
+		y = be16_to_cpu(tch->y);
+		z = tch->z;
+
+		cyttsp_report_slot(ts->input, slot, x, y, z);
+
+		ts->slot_status[slot] = true;
+	}
+
+	for (i = 0; i < CY_MAX_FINGER; i++)
+		if (ts->slot_status[i] == false &&
+		   ts->slots[i] != CY_SLOT_UNUSED) {
+			ts->slots[i] = CY_SLOT_UNUSED;
+			ts->slot_cnt--;
+			cyttsp_report_slot_empty(ts->input, i);
+		}
+
+	input_sync(ts->input);
+
+	return 0;
+}
+
+static void cyttsp_pr_state(struct cyttsp *ts)
+{
+	static char *cyttsp_powerstate_string[] = {
+		"IDLE",
+		"ACTIVE",
+		"LOW_PWR",
+		"SLEEP",
+		"BOOTLOADER",
+		"INVALID"
+	};
+
+	dev_info(ts->dev, "%s: %s\n", __func__,
+		ts->power_state < CY_INVALID_STATE ?
+		cyttsp_powerstate_string[ts->power_state] :
+		"INVALID");
+}
+
+static irqreturn_t cyttsp_irq(int irq, void *handle)
+{
+	struct cyttsp *ts = handle;
+	int retval;
+
+	if (ts->power_state == CY_BL_STATE)
+		complete(&ts->bl_ready);
+	else {
+		/* process the touches */
+		retval = cyttsp_xy_worker(ts);
+
+		if (retval < 0) {
+			/*
+			 * TTSP device has reset back to bootloader mode.
+			 * Restore to operational mode.
+			 */
+			retval = cyttsp_exit_bl_mode(ts);
+			if (retval)
+				ts->power_state = CY_IDLE_STATE;
+			else
+				ts->power_state = CY_ACTIVE_STATE;
+			cyttsp_pr_state(ts);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int cyttsp_power_on(struct cyttsp *ts)
+{
+	int retval = 0;
+
+	if (!ts)
+		return -ENOMEM;
+
+	ts->power_state = CY_BL_STATE;
+
+	/* enable interrupts */
+	retval = request_threaded_irq(ts->irq, NULL, cyttsp_irq,
+		IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+		ts->platform_data->name, ts);
+	if (retval < 0)
+		goto bypass;
+
+	retval = cyttsp_soft_reset(ts);
+	if (retval < 0)
+		goto bypass;
+
+	retval = cyttsp_bl_app_valid(ts);
+	if (retval < 0)
+		goto bypass;
+	else if (retval > 0)
+		goto no_bl_bypass;
+
+	retval = cyttsp_exit_bl_mode(ts);
+
+	if (retval < 0)
+		goto bypass;
+
+	ts->power_state = CY_IDLE_STATE;
+
+no_bl_bypass:
+	retval = cyttsp_set_sysinfo_mode(ts);
+	if (retval < 0)
+		goto bypass;
+
+	retval = cyttsp_set_sysinfo_regs(ts);
+	if (retval < 0)
+		goto bypass;
+
+	retval = cyttsp_set_operational_mode(ts);
+	if (retval < 0)
+		goto bypass;
+
+	/* init active distance */
+	retval = cyttsp_act_dist_setup(ts);
+	if (retval < 0)
+		goto bypass;
+
+	ts->power_state = CY_ACTIVE_STATE;
+	retval = 0;
+
+bypass:
+	cyttsp_pr_state(ts);
+	return retval;
+}
+
+#ifdef CONFIG_PM
+int cyttsp_resume(void *handle)
+{
+	struct cyttsp *ts = handle;
+	int retval = 0;
+	struct cyttsp_xydata xydata;
+
+	if (ts->platform_data->use_sleep && (ts->power_state !=
+		CY_ACTIVE_STATE)) {
+		if (ts->platform_data->wakeup) {
+			retval = ts->platform_data->wakeup();
+			if (retval < 0)
+				dev_dbg(ts->dev, "%s: Error, wakeup failed!\n",
+					__func__);
+		} else {
+			dev_dbg(ts->dev, "%s: Error, wakeup not implemented "
+				"(check board file).\n", __func__);
+			retval = -ENOSYS;
+		}
+		if (!(retval < 0)) {
+			retval = ttsp_read_block_data(ts, CY_REG_BASE,
+				sizeof(xydata), &xydata);
+			if (!(retval < 0) && !GET_HSTMODE(xydata.hst_mode))
+				ts->power_state = CY_ACTIVE_STATE;
+		}
+	}
+	dev_dbg(ts->dev, "%s: Wake Up %s\n", __func__,
+		(retval < 0) ? "FAIL" : "PASS");
+	return retval;
+}
+EXPORT_SYMBOL_GPL(cyttsp_resume);
+
+int cyttsp_suspend(void *handle)
+{
+	struct cyttsp *ts = handle;
+	u8 sleep_mode = 0;
+	int retval = 0;
+
+	if (ts->platform_data->use_sleep &&
+		(ts->power_state == CY_ACTIVE_STATE)) {
+		sleep_mode = CY_DEEP_SLEEP_MODE;
+		retval = ttsp_write_block_data(ts,
+			CY_REG_BASE, sizeof(sleep_mode), &sleep_mode);
+		if (!(retval < 0))
+			ts->power_state = CY_SLEEP_STATE;
+	}
+	dev_dbg(ts->dev, "%s: Sleep Power state is %s\n", __func__,
+		(ts->power_state == CY_ACTIVE_STATE) ?
+		"ACTIVE" :
+		((ts->power_state == CY_SLEEP_STATE) ?
+		"SLEEP" : "LOW POWER"));
+	return retval;
+}
+EXPORT_SYMBOL_GPL(cyttsp_suspend);
+#endif
+
+static int cyttsp_open(struct input_dev *dev)
+{
+	struct cyttsp *ts = input_get_drvdata(dev);
+
+	return cyttsp_power_on(ts);
+}
+
+void cyttsp_core_release(void *handle)
+{
+	struct cyttsp *ts = handle;
+
+	if (ts) {
+		free_irq(ts->irq, ts);
+		input_unregister_device(ts->input);
+		if (ts->platform_data->exit)
+			ts->platform_data->exit();
+		input_mt_destroy_slots(ts->input);
+		kfree(ts);
+	}
+}
+EXPORT_SYMBOL_GPL(cyttsp_core_release);
+
+static void cyttsp_close(struct input_dev *dev)
+{
+	struct cyttsp *ts = input_get_drvdata(dev);
+
+	free_irq(ts->irq, ts);
+}
+
+void *cyttsp_core_init(struct cyttsp_bus_ops *bus_ops, struct device *dev)
+{
+	struct input_dev *input_device;
+	int i;
+
+	struct cyttsp *ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+
+	if (!ts) {
+		pr_err("%s: Error, kzalloc\n", __func__);
+		goto error_alloc_data;
+	}
+
+	if (dev == NULL || bus_ops == NULL) {
+		kfree(ts);
+		goto error_alloc_data;
+	}
+
+	ts->dev = dev;
+	ts->platform_data = dev->platform_data;
+	ts->bus_ops = bus_ops;
+	init_completion(&ts->bl_ready);
+
+	if (ts->platform_data->init) {
+		if (ts->platform_data->init()) {
+			dev_dbg(ts->dev, "%s: Error, platform init failed!\n",
+				__func__);
+			goto error_init;
+		}
+	}
+
+	ts->irq = gpio_to_irq(ts->platform_data->irq_gpio);
+	if (ts->irq <= 0) {
+		dev_dbg(ts->dev, "%s: Error, failed to allocate irq\n",
+			__func__);
+			goto error_init;
+	}
+
+	/* Create the input device and register it. */
+	input_device = input_allocate_device();
+	if (!input_device) {
+		dev_dbg(ts->dev, "%s: Error, failed to allocate input device\n",
+			__func__);
+		goto error_input_allocate_device;
+	}
+
+	ts->input = input_device;
+	input_device->name = ts->platform_data->name;
+	snprintf(ts->phys, sizeof(ts->phys), "%s", dev_name(dev));
+	input_device->phys = ts->phys;
+	input_device->dev.parent = ts->dev;
+	ts->bus_type = bus_ops->dev->bus;
+	input_device->open = cyttsp_open;
+	input_device->close = cyttsp_close;
+	input_set_drvdata(input_device, ts);
+
+	__set_bit(EV_SYN, input_device->evbit);
+	__set_bit(EV_KEY, input_device->evbit);
+	__set_bit(EV_ABS, input_device->evbit);
+
+	input_set_abs_params(input_device, ABS_MT_POSITION_X,
+			     0, ts->platform_data->maxx, 0, 0);
+	input_set_abs_params(input_device, ABS_MT_POSITION_Y,
+			     0, ts->platform_data->maxy, 0, 0);
+	input_set_abs_params(input_device, ABS_MT_TOUCH_MAJOR,
+			     0, CY_MAXZ, 0, 0);
+
+	input_mt_init_slots(input_device, CY_MAX_FINGER);
+
+	for (i = 0; i < CY_MAX_FINGER; i++)
+		ts->slots[i] = CY_SLOT_UNUSED;
+
+	ts->slot_cnt = 0;
+
+	if (input_register_device(input_device)) {
+		dev_dbg(ts->dev, "%s: Error, failed to register input device\n",
+			__func__);
+		goto error_input_register_device;
+	}
+
+	goto no_error;
+
+error_input_register_device:
+	input_unregister_device(input_device);
+error_input_allocate_device:
+	if (ts->platform_data->exit)
+		ts->platform_data->exit();
+error_init:
+	kfree(ts);
+error_alloc_data:
+no_error:
+	return ts;
+}
+EXPORT_SYMBOL_GPL(cyttsp_core_init);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver core");
+MODULE_AUTHOR("Cypress");
+
diff --git a/drivers/input/touchscreen/cyttsp/cyttsp_core.h b/drivers/input/touchscreen/cyttsp/cyttsp_core.h
new file mode 100644
index 0000000..daa2bb8
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/cyttsp_core.h
@@ -0,0 +1,56 @@
+/*
+ * Header file for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) touchscreen drivers.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
+ *
+ */
+
+
+#ifndef __CYTTSP_CORE_H__
+#define __CYTTSP_CORE_H__
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/input/cyttsp.h>
+
+#define CY_NUM_RETRY                4 /* max number of retries for read ops */
+
+
+struct cyttsp_bus_ops {
+	s32 (*write)(void *handle, u8 addr, u8 length, const void *values);
+	s32 (*read)(void *handle, u8 addr, u8 length, void *values);
+	s32 (*ext)(void *handle, void *values);
+	struct device *dev;
+};
+
+void *cyttsp_core_init(struct cyttsp_bus_ops *bus_ops, struct device *dev);
+
+void cyttsp_core_release(void *handle);
+#ifdef CONFIG_PM
+int cyttsp_resume(void *handle);
+int cyttsp_suspend(void *handle);
+#endif
+
+#endif /* __CYTTSP_CORE_H__ */
diff --git a/include/linux/input/cyttsp.h b/include/linux/input/cyttsp.h
new file mode 100644
index 0000000..3907bfc
--- /dev/null
+++ b/include/linux/input/cyttsp.h
@@ -0,0 +1,68 @@
+/*
+ * Header file for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) touchscreen drivers.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com (kev@cypress.com)
+ *
+ */
+#ifndef _CYTTSP_H_
+#define _CYTTSP_H_
+
+#define CY_SPI_NAME "cyttsp-spi"
+#define CY_I2C_NAME "cyttsp-i2c"
+/* Active Power state scanning/processing refresh interval */
+#define CY_ACT_INTRVL_DFLT 0x00 /* ms */
+/* touch timeout for the Active power */
+#define CY_TCH_TMOUT_DFLT 0xFF /* ms */
+/* Low Power state scanning/processing refresh interval */
+#define CY_LP_INTRVL_DFLT 0x0A /* ms */
+/* Active distance in pixels for a gesture to be reported */
+#define CY_ACT_DIST_DFLT 0xF8 /* pixels */
+
+enum cyttsp_powerstate {
+	CY_IDLE_STATE,
+	CY_ACTIVE_STATE,
+	CY_LOW_PWR_STATE,
+	CY_SLEEP_STATE,
+	CY_BL_STATE,
+	CY_INVALID_STATE	/* always last in the list */
+};
+
+struct cyttsp_platform_data {
+	u32 maxx;
+	u32 maxy;
+	bool use_hndshk;
+	bool use_sleep;
+	u8 act_dist;	/* Active distance */
+	u8 act_intrvl;  /* Active refresh interval; ms */
+	u8 tch_tmout;   /* Active touch timeout; ms */
+	u8 lp_intrvl;   /* Low power refresh interval; ms */
+	int (*wakeup)(void);
+	int (*init)(void);
+	void (*exit)(void);
+	char *name;
+	s16 irq_gpio;
+	u8 *bl_keys;
+};
+
+#endif /* _CYTTSP_H_ */
-- 
1.7.4.1

[PATCH 2/3] Input: cyttsp - add support for Cypress TTSP touchscreen I2C bus interface

[Javier Martinez Canillas]

The driver is composed of a core driver that process the data sent by
the contacts and a set of bus specific interface modules.

This patch add supports for the Cypress TTSP I2C bus interface.

The original author of the driver is Kevin McNeely <kev@cypress.com>

Signed-off-by: Javier Martinez Canillas <martinez.javier@gmail.com>
---
 drivers/input/touchscreen/cyttsp/Kconfig      |   12 ++
 drivers/input/touchscreen/cyttsp/Makefile     |    1 +
 drivers/input/touchscreen/cyttsp/cyttsp_i2c.c |  188 +++++++++++++++++++++++++
 3 files changed, 201 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/touchscreen/cyttsp/cyttsp_i2c.c

diff --git a/drivers/input/touchscreen/cyttsp/Kconfig b/drivers/input/touchscreen/cyttsp/Kconfig
index 7e8e0f4..256642d 100644
--- a/drivers/input/touchscreen/cyttsp/Kconfig
+++ b/drivers/input/touchscreen/cyttsp/Kconfig
@@ -2,3 +2,15 @@ config TOUCHSCREEN_CYTTSP_CORE
 	tristate "Cypress TTSP touchscreen core"
 	help
 	  Always activated for Cypress TTSP touchscreen
+
+config TOUCHSCREEN_CYTTSP_I2C
+	tristate "Cypress TTSP i2c touchscreen"
+	depends on I2C && TOUCHSCREEN_CYTTSP_CORE
+	help
+	  Say Y here if you have a Cypress TTSP touchscreen
+	  connected to your system with an I2C interface.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cyttsp-i2c.
diff --git a/drivers/input/touchscreen/cyttsp/Makefile b/drivers/input/touchscreen/cyttsp/Makefile
index d1b250f..9101dc9 100644
--- a/drivers/input/touchscreen/cyttsp/Makefile
+++ b/drivers/input/touchscreen/cyttsp/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)   += cyttsp_core.o
+obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C)    += cyttsp_i2c.o
diff --git a/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c b/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c
new file mode 100644
index 0000000..d79c6a7
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c
@@ -0,0 +1,188 @@
+/*
+ * Source for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
+ *
+ */
+
+#include "cyttsp_core.h"
+
+#include <linux/i2c.h>
+#include <linux/slab.h>
+
+#define CY_I2C_DATA_SIZE  128
+
+struct cyttsp_i2c {
+	struct cyttsp_bus_ops ops;
+	struct i2c_client *client;
+	void *ttsp_client;
+	u8 wr_buf[CY_I2C_DATA_SIZE];
+};
+
+static s32 ttsp_i2c_read_block_data(void *handle, u8 addr,
+	u8 length, void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval = 0;
+
+	retval = i2c_master_send(ts->client, &addr, 1);
+	if (retval < 0)
+		return retval;
+
+	retval = i2c_master_recv(ts->client, values, length);
+
+	return (retval < 0) ? retval : 0;
+}
+
+static s32 ttsp_i2c_write_block_data(void *handle, u8 addr,
+	u8 length, const void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval;
+
+	ts->wr_buf[0] = addr;
+	memcpy(&ts->wr_buf[1], values, length);
+
+	retval = i2c_master_send(ts->client, ts->wr_buf, length+1);
+
+	return (retval < 0) ? retval : 0;
+}
+
+static s32 ttsp_i2c_tch_ext(void *handle, void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval = 0;
+
+	/*
+	 * TODO: Add custom touch extension handling code here
+	 * set: retval < 0 for any returned system errors,
+	 *	retval = 0 if normal touch handling is required,
+	 *	retval > 0 if normal touch handling is *not* required
+	 */
+	if (!ts || !values)
+		retval = -EINVAL;
+
+	return retval;
+}
+
+static int __devinit cyttsp_i2c_probe(struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct cyttsp_i2c *ts;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -EIO;
+
+	/* allocate and clear memory */
+	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+	if (!ts) {
+		dev_dbg(&client->dev, "%s: Error, kzalloc.\n", __func__);
+		return -ENOMEM;
+	}
+
+	/* register driver_data */
+	ts->client = client;
+	i2c_set_clientdata(client, ts);
+	ts->ops.write = ttsp_i2c_write_block_data;
+	ts->ops.read = ttsp_i2c_read_block_data;
+	ts->ops.ext = ttsp_i2c_tch_ext;
+	ts->ops.dev = &client->dev;
+	ts->ops.dev->bus = &i2c_bus_type;
+
+	ts->ttsp_client = cyttsp_core_init(&ts->ops, &client->dev);
+	if (IS_ERR(ts->ttsp_client)) {
+		int retval = PTR_ERR(ts->ttsp_client);
+		kfree(ts);
+		return retval;
+	}
+
+	dev_dbg(ts->ops.dev, "%s: Registration complete\n", __func__);
+
+	return 0;
+}
+
+
+/* registered in driver struct */
+static int __devexit cyttsp_i2c_remove(struct i2c_client *client)
+{
+	struct cyttsp_i2c *ts;
+
+	ts = i2c_get_clientdata(client);
+	cyttsp_core_release(ts->ttsp_client);
+	kfree(ts);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int cyttsp_i2c_suspend(struct i2c_client *client, pm_message_t message)
+{
+	struct cyttsp_i2c *ts = i2c_get_clientdata(client);
+
+	return cyttsp_suspend(ts->ttsp_client);
+}
+
+static int cyttsp_i2c_resume(struct i2c_client *client)
+{
+	struct cyttsp_i2c *ts = i2c_get_clientdata(client);
+
+	return cyttsp_resume(ts->ttsp_client);
+}
+#endif
+
+static const struct i2c_device_id cyttsp_i2c_id[] = {
+	{ CY_I2C_NAME, 0 },  { }
+};
+
+static struct i2c_driver cyttsp_i2c_driver = {
+	.driver = {
+		.name = CY_I2C_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe = cyttsp_i2c_probe,
+	.remove = __devexit_p(cyttsp_i2c_remove),
+	.id_table = cyttsp_i2c_id,
+#ifdef CONFIG_PM
+	.suspend = cyttsp_i2c_suspend,
+	.resume = cyttsp_i2c_resume,
+#endif
+};
+
+static int __init cyttsp_i2c_init(void)
+{
+	return i2c_add_driver(&cyttsp_i2c_driver);
+}
+
+static void __exit cyttsp_i2c_exit(void)
+{
+	return i2c_del_driver(&cyttsp_i2c_driver);
+}
+
+module_init(cyttsp_i2c_init);
+module_exit(cyttsp_i2c_exit);
+
+MODULE_ALIAS("i2c:cyttsp");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
+MODULE_AUTHOR("Cypress");
+MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id);
-- 
1.7.4.1

[PATCH 3/3] Input: cyttsp - add support for Cypress TTSP touchscreen SPI bus interface

[Javier Martinez Canillas]

The driver is composed of a core driver that process the data sent by
the contacts and a set of bus specific interface modules.

This patch add supports for the Cypress TTSP SPI bus interface.

The original author of the driver is Kevin McNeely <kev@cypress.com>

Signed-off-by: Javier Martinez Canillas <martinez.javier@gmail.com>
---
 drivers/input/touchscreen/cyttsp/Kconfig      |   12 +
 drivers/input/touchscreen/cyttsp/Makefile     |    1 +
 drivers/input/touchscreen/cyttsp/cyttsp_spi.c |  318 +++++++++++++++++++++++++
 3 files changed, 331 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/touchscreen/cyttsp/cyttsp_spi.c

diff --git a/drivers/input/touchscreen/cyttsp/Kconfig b/drivers/input/touchscreen/cyttsp/Kconfig
index 256642d..e72c66c 100644
--- a/drivers/input/touchscreen/cyttsp/Kconfig
+++ b/drivers/input/touchscreen/cyttsp/Kconfig
@@ -14,3 +14,15 @@ config TOUCHSCREEN_CYTTSP_I2C
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called cyttsp-i2c.
+
+config TOUCHSCREEN_CYTTSP_SPI
+	tristate "Cypress TTSP spi touchscreen"
+	depends on SPI_MASTER && TOUCHSCREEN_CYTTSP_CORE
+	help
+	  Say Y here if you have a Cypress TTSP touchscreen
+	  connected to your  with an SPI interface.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cyttsp-spi.
diff --git a/drivers/input/touchscreen/cyttsp/Makefile b/drivers/input/touchscreen/cyttsp/Makefile
index 9101dc9..687eeaa 100644
--- a/drivers/input/touchscreen/cyttsp/Makefile
+++ b/drivers/input/touchscreen/cyttsp/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)   += cyttsp_core.o
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C)    += cyttsp_i2c.o
+obj-$(CONFIG_TOUCHSCREEN_CYTTSP_SPI)    += cyttsp_spi.o
diff --git a/drivers/input/touchscreen/cyttsp/cyttsp_spi.c b/drivers/input/touchscreen/cyttsp/cyttsp_spi.c
new file mode 100644
index 0000000..108c37f
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/cyttsp_spi.c
@@ -0,0 +1,318 @@
+/*
+ * Source for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) SPI touchscreen driver.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
+ *
+ */
+
+#include "cyttsp_core.h"
+
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+
+#define CY_SPI_WR_OP      0x00 /* r/~w */
+#define CY_SPI_RD_OP      0x01
+#define CY_SPI_CMD_BYTES  4
+#define CY_SPI_SYNC_BYTE  2
+#define CY_SPI_SYNC_ACK1  0x62 /* from protocol v.2 */
+#define CY_SPI_SYNC_ACK2  0x9D /* from protocol v.2 */
+#define CY_SPI_DATA_SIZE  128
+#define CY_SPI_DATA_BUF_SIZE (CY_SPI_CMD_BYTES + CY_SPI_DATA_SIZE)
+#define CY_SPI_BITS_PER_WORD 8
+
+struct cyttsp_spi {
+	struct cyttsp_bus_ops ops;
+	struct spi_device *spi_client;
+	void *ttsp_client;
+	u8 wr_buf[CY_SPI_DATA_BUF_SIZE];
+	u8 rd_buf[CY_SPI_DATA_BUF_SIZE];
+};
+
+static void spi_complete(void *arg)
+{
+	complete(arg);
+}
+
+static int spi_sync_tmo(struct cyttsp_spi *ts, struct spi_message *message)
+{
+	DECLARE_COMPLETION_ONSTACK(done);
+	int status;
+
+	message->complete = spi_complete;
+	message->context = &done;
+	status = spi_async(ts->spi_client, message);
+	if (status == 0) {
+		int ret = wait_for_completion_interruptible_timeout(&done, HZ);
+		if (!ret) {
+			dev_dbg(ts->ops.dev, "%s: timeout\n", __func__);
+			status = -EIO;
+		} else
+			status = message->status;
+	}
+	message->context = NULL;
+	return status;
+}
+
+static int cyttsp_spi_xfer_(u8 op, struct cyttsp_spi *ts,
+			    u8 reg, u8 *buf, int length)
+{
+	struct spi_message msg;
+	struct spi_transfer xfer[2];
+	u8 *wr_buf = ts->wr_buf;
+	u8 *rd_buf = ts->rd_buf;
+	int retval;
+
+	if (length > CY_SPI_DATA_SIZE) {
+		dev_dbg(ts->ops.dev, "%s: length %d is too big.\n",
+			__func__, length);
+		return -EINVAL;
+	}
+
+	memset(wr_buf, 0, CY_SPI_DATA_BUF_SIZE);
+	memset(rd_buf, 0, CY_SPI_DATA_BUF_SIZE);
+
+	wr_buf[0] = 0x00; /* header byte 0 */
+	wr_buf[1] = 0xFF; /* header byte 1 */
+	wr_buf[2] = reg;  /* reg index */
+	wr_buf[3] = op;   /* r/~w */
+	if (op == CY_SPI_WR_OP)
+		memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length);
+
+	memset((void *)xfer, 0, sizeof(xfer));
+	spi_message_init(&msg);
+	xfer[0].tx_buf = wr_buf;
+	xfer[0].rx_buf = rd_buf;
+	if (op == CY_SPI_WR_OP) {
+		xfer[0].len = length + CY_SPI_CMD_BYTES;
+		spi_message_add_tail(&xfer[0], &msg);
+	} else if (op == CY_SPI_RD_OP) {
+		xfer[0].len = CY_SPI_CMD_BYTES;
+		spi_message_add_tail(&xfer[0], &msg);
+
+		xfer[1].rx_buf = buf;
+		xfer[1].len = length;
+		spi_message_add_tail(&xfer[1], &msg);
+	}
+
+	retval = spi_sync_tmo(ts, &msg);
+	if (retval < 0) {
+		dev_dbg(ts->ops.dev, "%s: spi sync error %d, len=%d, op=%d\n",
+			__func__, retval, xfer[1].len, op);
+		retval = 0;
+	}
+
+	if (op == CY_SPI_RD_OP) {
+		if ((rd_buf[CY_SPI_SYNC_BYTE] == CY_SPI_SYNC_ACK1) &&
+			(rd_buf[CY_SPI_SYNC_BYTE+1] == CY_SPI_SYNC_ACK2))
+			retval = 0;
+		else {
+			int i;
+			for (i = 0; i < (CY_SPI_CMD_BYTES); i++)
+				dev_dbg(ts->ops.dev,
+					"%s: test rd_buf[%d]:0x%02x\n",
+					__func__, i, rd_buf[i]);
+			for (i = 0; i < (length); i++)
+				dev_dbg(ts->ops.dev,
+					"%s: test buf[%d]:0x%02x\n",
+					__func__, i, buf[i]);
+			retval = 1;
+		}
+	}
+	return retval;
+}
+
+static int cyttsp_spi_xfer(u8 op, struct cyttsp_spi *ts,
+			    u8 reg, u8 *buf, int length)
+{
+	int tries;
+	int retval;
+
+	if (op == CY_SPI_RD_OP) {
+		for (tries = CY_NUM_RETRY; tries; tries--) {
+			retval = cyttsp_spi_xfer_(op, ts, reg, buf, length);
+			if (retval == 0)
+				break;
+			else
+				msleep(20);
+		}
+	} else {
+		retval = cyttsp_spi_xfer_(op, ts, reg, buf, length);
+	}
+
+	return retval;
+}
+
+static s32 ttsp_spi_read_block_data(void *handle, u8 addr,
+				    u8 length, void *data)
+{
+	struct cyttsp_spi *ts = container_of(handle, struct cyttsp_spi, ops);
+	int retval;
+
+	retval = cyttsp_spi_xfer(CY_SPI_RD_OP, ts, addr, data, length);
+	if (retval < 0)
+		dev_dbg(ts->ops.dev,  "%s: ttsp_spi_read_block_data failed\n",
+			__func__);
+
+	/*
+	 * Do not print the above error if the data sync bytes were not found.
+	 * This is a normal condition for the bootloader loader startup and need
+	 * to retry until data sync bytes are found.
+	 */
+	if (retval > 0)
+		retval = -1;	/* now signal fail; so retry can be done */
+
+	return retval;
+}
+
+static s32 ttsp_spi_write_block_data(void *handle, u8 addr,
+				     u8 length, const void *data)
+{
+	struct cyttsp_spi *ts = container_of(handle, struct cyttsp_spi, ops);
+	int retval;
+
+	retval = cyttsp_spi_xfer(CY_SPI_WR_OP, ts, addr, (void *)data, length);
+	if (retval < 0)
+		dev_dbg(ts->ops.dev, "%s: ttsp_spi_write_block_data failed\n",
+			__func__);
+
+	if (retval == -EIO)
+		return 0;
+	else
+		return retval;
+}
+
+static s32 ttsp_spi_tch_ext(void *handle, void *values)
+{
+	struct cyttsp_spi *ts = container_of(handle, struct cyttsp_spi, ops);
+	int retval = 0;
+
+	/*
+	 * TODO: Add custom touch extension handling code here
+	 * set: retval < 0 for any returned system errors,
+	 *	retval = 0 if normal touch handling is required,
+	 *	retval > 0 if normal touch handling is *not* required
+	 */
+
+	if (!ts || !values)
+		retval = -EINVAL;
+
+	return retval;
+}
+
+static int __devinit cyttsp_spi_probe(struct spi_device *spi)
+{
+	struct cyttsp_spi *ts;
+	int retval;
+
+	/* Set up SPI*/
+	spi->bits_per_word = CY_SPI_BITS_PER_WORD;
+	spi->mode = SPI_MODE_0;
+	retval = spi_setup(spi);
+	if (retval < 0) {
+		dev_dbg(&spi->dev, "%s: SPI setup error %d\n",
+			__func__, retval);
+		return retval;
+	}
+
+	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+	if (!ts) {
+		dev_dbg(&spi->dev, "%s: Error, kzalloc\n", __func__);
+		return -ENOMEM;
+	}
+
+	ts->spi_client = spi;
+	dev_set_drvdata(&spi->dev, ts);
+	ts->ops.write = ttsp_spi_write_block_data;
+	ts->ops.read = ttsp_spi_read_block_data;
+	ts->ops.ext = ttsp_spi_tch_ext;
+	ts->ops.dev = &spi->dev;
+
+	ts->ttsp_client = cyttsp_core_init(&ts->ops, &spi->dev);
+	if (IS_ERR(ts->ttsp_client)) {
+		int retval = PTR_ERR(ts->ttsp_client);
+		kfree(ts);
+		return retval;
+	}
+
+	dev_dbg(ts->ops.dev, "%s: Registration complete\n", __func__);
+
+	return 0;
+}
+
+static int __devexit cyttsp_spi_remove(struct spi_device *spi)
+{
+	struct cyttsp_spi *ts = dev_get_drvdata(&spi->dev);
+
+	cyttsp_core_release(ts->ttsp_client);
+	kfree(ts);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int cyttsp_spi_suspend(struct spi_device *spi, pm_message_t message)
+{
+	struct cyttsp_spi *ts = dev_get_drvdata(&spi->dev);
+
+	return cyttsp_suspend(ts->ttsp_client);
+}
+
+static int cyttsp_spi_resume(struct spi_device *spi)
+{
+	struct cyttsp_spi *ts = dev_get_drvdata(&spi->dev);
+
+	return cyttsp_resume(ts->ttsp_client);
+}
+#endif
+
+static struct spi_driver cyttsp_spi_driver = {
+	.driver = {
+		.name = CY_SPI_NAME,
+		.bus = &spi_bus_type,
+		.owner = THIS_MODULE,
+	},
+	.probe = cyttsp_spi_probe,
+	.remove = __devexit_p(cyttsp_spi_remove),
+#ifdef CONFIG_PM
+	.suspend = cyttsp_spi_suspend,
+	.resume = cyttsp_spi_resume,
+#endif
+};
+
+static int __init cyttsp_spi_init(void)
+{
+	return spi_register_driver(&cyttsp_spi_driver);
+}
+module_init(cyttsp_spi_init);
+
+static void __exit cyttsp_spi_exit(void)
+{
+	spi_unregister_driver(&cyttsp_spi_driver);
+}
+module_exit(cyttsp_spi_exit);
+
+MODULE_ALIAS("spi:cyttsp");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver");
+MODULE_AUTHOR("Cypress");
+
-- 
1.7.4.1

Re: [PATCH 3/3] Input: cyttsp - add support for Cypress TTSP touchscreen SPI bus interface

[Dmitry Torokhov]

Hi Javier,

On Sat, Aug 20, 2011 at 12:01:52AM -0400, Javier Martinez Canillas wrote:
> +
> +static int cyttsp_spi_xfer_(u8 op, struct cyttsp_spi *ts,
> +			    u8 reg, u8 *buf, int length)
> +{
> +	struct spi_message msg;
> +	struct spi_transfer xfer[2];
> +	u8 *wr_buf = ts->wr_buf;
> +	u8 *rd_buf = ts->rd_buf;
> +	int retval;
> +
> +	if (length > CY_SPI_DATA_SIZE) {
> +		dev_dbg(ts->ops.dev, "%s: length %d is too big.\n",
> +			__func__, length);
> +		return -EINVAL;
> +	}
> +
> +	memset(wr_buf, 0, CY_SPI_DATA_BUF_SIZE);
> +	memset(rd_buf, 0, CY_SPI_DATA_BUF_SIZE);
> +
> +	wr_buf[0] = 0x00; /* header byte 0 */
> +	wr_buf[1] = 0xFF; /* header byte 1 */
> +	wr_buf[2] = reg;  /* reg index */
> +	wr_buf[3] = op;   /* r/~w */
> +	if (op == CY_SPI_WR_OP)
> +		memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length);
> +
> +	memset((void *)xfer, 0, sizeof(xfer));
> +	spi_message_init(&msg);
> +	xfer[0].tx_buf = wr_buf;
> +	xfer[0].rx_buf = rd_buf;

Since we are setting both TX and RX buffer here does this mean that the
device will not work with controllers in half-duplex mode? What is the
amount of data that will be placed in rd_buf?

> +	if (op == CY_SPI_WR_OP) {
> +		xfer[0].len = length + CY_SPI_CMD_BYTES;
> +		spi_message_add_tail(&xfer[0], &msg);
> +	} else if (op == CY_SPI_RD_OP) {
> +		xfer[0].len = CY_SPI_CMD_BYTES;
> +		spi_message_add_tail(&xfer[0], &msg);
> +
> +		xfer[1].rx_buf = buf;
> +		xfer[1].len = length;
> +		spi_message_add_tail(&xfer[1], &msg);
> +	}
> +
> +	retval = spi_sync_tmo(ts, &msg);
> +	if (retval < 0) {
> +		dev_dbg(ts->ops.dev, "%s: spi sync error %d, len=%d, op=%d\n",
> +			__func__, retval, xfer[1].len, op);
> +		retval = 0;

Why do we ignore the error?

> +	}
> +
> +	if (op == CY_SPI_RD_OP) {
> +		if ((rd_buf[CY_SPI_SYNC_BYTE] == CY_SPI_SYNC_ACK1) &&
> +			(rd_buf[CY_SPI_SYNC_BYTE+1] == CY_SPI_SYNC_ACK2))
> +			retval = 0;

What about write operation? Does the device send anything in rd_buf for
write command?

> +		else {
> +			int i;
> +			for (i = 0; i < (CY_SPI_CMD_BYTES); i++)
> +				dev_dbg(ts->ops.dev,
> +					"%s: test rd_buf[%d]:0x%02x\n",
> +					__func__, i, rd_buf[i]);
> +			for (i = 0; i < (length); i++)
> +				dev_dbg(ts->ops.dev,
> +					"%s: test buf[%d]:0x%02x\n",
> +					__func__, i, buf[i]);
> +			retval = 1;
> +		}
> +	}
> +	return retval;
> +}
> +
> +static int cyttsp_spi_xfer(u8 op, struct cyttsp_spi *ts,
> +			    u8 reg, u8 *buf, int length)
> +{
> +	int tries;
> +	int retval;
> +
> +	if (op == CY_SPI_RD_OP) {
> +		for (tries = CY_NUM_RETRY; tries; tries--) {
> +			retval = cyttsp_spi_xfer_(op, ts, reg, buf, length);
> +			if (retval == 0)
> +				break;
> +			else
> +				msleep(20);

Why do we need retry in SPI case but do not need it when device is
connected via I2C? And not on writes?

> +		}
> +	} else {
> +		retval = cyttsp_spi_xfer_(op, ts, reg, buf, length);
> +	}
> +
> +	return retval;
> +}
> +
> +static s32 ttsp_spi_read_block_data(void *handle, u8 addr,
> +				    u8 length, void *data)
> +{
> +	struct cyttsp_spi *ts = container_of(handle, struct cyttsp_spi, ops);
> +	int retval;
> +
> +	retval = cyttsp_spi_xfer(CY_SPI_RD_OP, ts, addr, data, length);
> +	if (retval < 0)
> +		dev_dbg(ts->ops.dev,  "%s: ttsp_spi_read_block_data failed\n",
> +			__func__);
> +
> +	/*
> +	 * Do not print the above error if the data sync bytes were not found.
> +	 * This is a normal condition for the bootloader loader startup and need
> +	 * to retry until data sync bytes are found.
> +	 */
> +	if (retval > 0)
> +		retval = -1;	/* now signal fail; so retry can be done */
> +
> +	return retval;
> +}
> +
> +static s32 ttsp_spi_write_block_data(void *handle, u8 addr,
> +				     u8 length, const void *data)
> +{
> +	struct cyttsp_spi *ts = container_of(handle, struct cyttsp_spi, ops);
> +	int retval;
> +
> +	retval = cyttsp_spi_xfer(CY_SPI_WR_OP, ts, addr, (void *)data, length);
> +	if (retval < 0)
> +		dev_dbg(ts->ops.dev, "%s: ttsp_spi_write_block_data failed\n",
> +			__func__);
> +
> +	if (retval == -EIO)
> +		return 0;

Why is -EIO special?

> +	else
> +		return retval;
> +}
> +

Thanks.

-- 
Dmitry

Re: [PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support

[Dmitry Torokhov]

Hi Javier,

On Sat, Aug 20, 2011 at 12:01:50AM -0400, Javier Martinez Canillas wrote:
> Cypress TrueTouch(tm) Standard Product controllers are found in
> a wide range of embedded devices. This driver add support for a
> variety of TTSP controllers.
> 
> The driver is composed of a core driver that process the data sent by
> the contacts and a set of bus specific interface modules. This patch
> adds the base core TTSP driver.
> 
> The original author of the driver is Kevin McNeely <kev@cypress.com>
> 
> Since the hardware is capable of tracking identifiable contacts and the
> original driver used multi-touch protocol type A (stateless), multi-touch
> protocol type B (stateful) support was added by Javier Martinez Canillas.
> 

Still reading through the patches, but have one question:

> +
> +	ts->irq = gpio_to_irq(ts->platform_data->irq_gpio);
> +	if (ts->irq <= 0) {
> +		dev_dbg(ts->dev, "%s: Error, failed to allocate irq\n",
> +			__func__);
> +			goto error_init;
> +	}

Why do we need to get gpio/irq from platform data instead of having
board code set up controllers appropriately and use IRQ either from I2C
client structure or from SPI?

Thanks.

-- 
Dmitry

Re: [PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support

[Javier Martinez Canillas]

On Mon, Aug 22, 2011 at 12:31 AM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> Hi Javier,
>

Hi Dmitry,

Thank you very much for the review.

>
> Still reading through the patches, but have one question:
>
>
> Why do we need to get gpio/irq from platform data instead of having
> board code set up controllers appropriately and use IRQ either from I2C
> client structure or from SPI?
>
> Thanks.
>
> --
> Dmitry
>

The original author of this driver is Kevin McNeely (cc'ed in this
patch submission).
I've only added multi-touch protocol type B support (which was a
requirement for upstream acceptance) and resubmit the patch-set.

I think he will better answer your questions about the driver design.

Kevin?

Best regards,

-- 
Javier Martínez Canillas
(+34) 682 39 81 69
Barcelona, Spain

Re: [PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support

[Javier Martinez Canillas]

On Mon, Aug 22, 2011 at 12:31 AM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> Hi Javier,
>

Hi Dmitry,

Thank you very much for the review.

>
> Still reading through the patches, but have one question:
>
>
> Why do we need to get gpio/irq from platform data instead of having
> board code set up controllers appropriately and use IRQ either from I2C
> client structure or from SPI?
>
> Thanks.
>
> --
> Dmitry
>

The original author of this driver is Kevin McNeely (cc'ed in this
patch submission).
I've only added multi-touch protocol type B support (which was a
requirement for upstream acceptance) and resubmit the patch-set.

I think he will better answer your questions about the driver design.

Kevin?

Best regards,

-- 
Javier Martínez Canillas
(+34) 682 39 81 69
Barcelona, Spain
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Re: [PATCH 3/3] Input: cyttsp - add support for Cypress TTSP touchscreen SPI bus interface

[Javier Martinez Canillas]

Hello Dmitry,

On Sun, 2011-08-21 at 19:44 -0700, Dmitry Torokhov wrote:
> Hi Javier,
> 
> > +
> > +	memset((void *)xfer, 0, sizeof(xfer));
> > +	spi_message_init(&msg);
> > +	xfer[0].tx_buf = wr_buf;
> > +	xfer[0].rx_buf = rd_buf;
> 
> Since we are setting both TX and RX buffer here does this mean that the
> device will not work with controllers in half-duplex mode? What is the
> amount of data that will be placed in rd_buf?
> 

Both TX and RX buffers are set because Cypress requires full duplex
operation always.

> > +	retval = spi_sync_tmo(ts, &msg);
> > +	if (retval < 0) {
> > +		dev_dbg(ts->ops.dev, "%s: spi sync error %d, len=%d, op=%d\n",
> > +			__func__, retval, xfer[1].len, op);
> > +		retval = 0;
> 
> Why do we ignore the error?
> 

Fixed: In next version a following ACK check code return the status to
the cyttsp core so it can retry after waiting with an msleep() call.

> > +	}
> > +
> > +	if (op == CY_SPI_RD_OP) {
> > +		if ((rd_buf[CY_SPI_SYNC_BYTE] == CY_SPI_SYNC_ACK1) &&
> > +			(rd_buf[CY_SPI_SYNC_BYTE+1] == CY_SPI_SYNC_ACK2))
> > +			retval = 0;
> 
> What about write operation? Does the device send anything in rd_buf for
> write command?
> 

Fixed: Both read and write operations check the ACK bytes now.

> > +
> > +	if (op == CY_SPI_RD_OP) {
> > +		for (tries = CY_NUM_RETRY; tries; tries--) {
> > +			retval = cyttsp_spi_xfer_(op, ts, reg, buf, length);
> > +			if (retval == 0)
> > +				break;
> > +			else
> > +				msleep(20);
> 
> Why do we need retry in SPI case but do not need it when device is
> connected via I2C? And not on writes?
> 

Fixed: The retries now are made in the cyttsp core so it works both for
SPI and I2C.

> > +
> > +	if (retval == -EIO)
> > +		return 0;
> 
> Why is -EIO special?
> 

Fixed: Now special EIO has been fixed to show meaning.

> > +	else
> > +		return retval;
> > +}
> > +
> 
> Thanks.
> 
> -- 
> Dmitry

Best regards,

Javier Martinez Canillas

Re: [PATCH 1/3] Input: cyttsp - Cypress TTSP capacitive multi-touch screen support

[Javier Martinez Canillas]

Hello Dmitry,

On Sun, 2011-08-21 at 21:31 -0700, Dmitry Torokhov wrote:
> Hi Javier,
 
> 
> Still reading through the patches, but have one question:
> 
> > +
> > +	ts->irq = gpio_to_irq(ts->platform_data->irq_gpio);
> > +	if (ts->irq <= 0) {
> > +		dev_dbg(ts->dev, "%s: Error, failed to allocate irq\n",
> > +			__func__);
> > +			goto error_init;
> > +	}
> 
> Why do we need to get gpio/irq from platform data instead of having
> board code set up controllers appropriately and use IRQ either from I2C
> client structure or from SPI?
> 
> Thanks.
> 

Right, next version fix this by extracting the IRQ either from the I2C
or SPI client data structure as you suggest.

Best regards,

Javier Martinez Canillas