* [PATCH 2/2 V4] Input: add Atmel Captouch Button driver
@ 2016-05-17 19:29 Grant Grundler
2016-05-18 21:59 ` Dmitry Torokhov
0 siblings, 1 reply; 4+ messages in thread
From: Grant Grundler @ 2016-05-17 19:29 UTC (permalink / raw)
To: Rob Herring, Pawel Moll, Mark Rutland, Dmitry Torokhov
Cc: devicetree, linux-input, LKML, Hung-yu Wu, Kumar Gala,
Ian Campbell, Grant Likely, Grant Grundler
From: Daniel Hung-yu Wu <hywu@google.com>
Add I2C driver for Atmel Capacitive Touch Button device.
Signed-off-by: Hung-yu Wu <hywu@google.com>
Signed-off-by: Grant Grundler <grundler@chromium.org>
---
drivers/input/misc/Kconfig | 13 ++
drivers/input/misc/Makefile | 1 +
drivers/input/misc/atmel_captouch.c | 287 ++++++++++++++++++++++++++++++++++++
3 files changed, 299 insertions(+)
create mode 100644 drivers/input/misc/atmel_captouch.c
V4: wordsmithing comments at top of file.
Added missing semicolon to CONFIG_OF data struct.
V3: use dash, not underscore in nodename. Wordsmith Kconfig help text.
V2: split Documentation/devicetree/bindings from driver patch.
rename "atmel,atmegaxx_captouch" to "atmel,captouch" since it's irrelevant
which controller implements the register set/controller.
V1: posted https://lkml.org/lkml/2016/5/3/613
diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 838824b..d8b6620 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -82,6 +82,19 @@ config INPUT_ARIZONA_HAPTICS
To compile this driver as a module, choose M here: the
module will be called arizona-haptics.
+config INPUT_ATMEL_CAPTOUCH
+ tristate "Atmel Capacitive Touch Button Driver"
+ depends on OF || COMPILE_TEST
+ help
+ Say Y here if an Atmel Capacitive Touch Button device which
+ implements "captouch" protocol is connected to I2C bus. Typically
+ this device consists of Atmel Touch sensor controlled by AtMegaXX
+ MCU running firmware based on Qtouch library.
+ One should find "atmel,captouch" node in the board specific DTS.
+
+ To compile this driver as a module, choose M here: the
+ module will be called atmel_captouch.
+
config INPUT_BMA150
tristate "BMA150/SMB380 acceleration sensor support"
depends on I2C
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index f77268e..b5ec626 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_INPUT_APANEL) += apanel.o
obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o
obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o
obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o
+obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o
obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o
obj-$(CONFIG_INPUT_BMA150) += bma150.o
obj-$(CONFIG_INPUT_CM109) += cm109.o
diff --git a/drivers/input/misc/atmel_captouch.c b/drivers/input/misc/atmel_captouch.c
new file mode 100644
index 0000000..91bfc73
--- /dev/null
+++ b/drivers/input/misc/atmel_captouch.c
@@ -0,0 +1,287 @@
+/*
+ * Atmel Capacitive Touch Button Driver
+ *
+ * Copyright (C) 2016 Google, inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+/*
+ * It's irrelevant the HW used to develop captouch driver is based
+ * on Atmega88PA part and uses QtouchADC parts for sensing touch.
+ * Calling this driver "captouch" is an arbitrary way to distinguish
+ * the protocol this driver supports from other atmel/qtouch drivers.
+ *
+ * captouch driver supports a newer/different version of the I2C
+ * registers/commands than the qt1070.c driver.
+ * Don't let the similarity of the general driver structure fool you. :)
+ *
+ * For raw i2c access from userspace, use i2cset/i2cget
+ * to poke at /dev/i2c-N devices.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+/* Maximum number of buttons supported */
+#define MAX_NUM_OF_BUTTONS 8
+
+/* Registers */
+#define REG_KEY1_THRESHOLD 0x02
+#define REG_KEY2_THRESHOLD 0x03
+#define REG_KEY3_THRESHOLD 0x04
+#define REG_KEY4_THRESHOLD 0x05
+
+#define REG_KEY1_REF_H 0x20
+#define REG_KEY1_REF_L 0x21
+#define REG_KEY2_REF_H 0x22
+#define REG_KEY2_REF_L 0x23
+#define REG_KEY3_REF_H 0x24
+#define REG_KEY3_REF_L 0x25
+#define REG_KEY4_REF_H 0x26
+#define REG_KEY4_REF_L 0x27
+
+#define REG_KEY1_DLT_H 0x30
+#define REG_KEY1_DLT_L 0x31
+#define REG_KEY2_DLT_H 0x32
+#define REG_KEY2_DLT_L 0x33
+#define REG_KEY3_DLT_H 0x34
+#define REG_KEY3_DLT_L 0x35
+#define REG_KEY4_DLT_H 0x36
+#define REG_KEY4_DLT_L 0x37
+
+#define REG_KEY_STATE 0x3C
+
+/*
+ * @i2c_client: I2C slave device client pointer
+ * @input: Input device pointer
+ * @num_btn: Number of buttons
+ * @keycodes: map of button# to KeyCode
+ * @prev_btn: Previous key state to detect button "press" or "release"
+ * @xfer_buf: I2C transfer buffer
+ */
+struct atmel_captouch_device {
+ struct i2c_client *client;
+ struct input_dev *input;
+ u32 num_btn;
+ u32 keycodes[MAX_NUM_OF_BUTTONS];
+ u8 prev_btn;
+ u8 xfer_buf[8] ____cacheline_aligned;
+};
+
+/*
+ * Read from I2C slave device
+ * The protocol is that the client has to provide both the register address
+ * and the length, and while reading back the device would prepend the data
+ * with address and length for verification.
+ */
+static int atmel_read(struct atmel_captouch_device *capdev,
+ u8 reg, u8 *data, size_t len)
+{
+ struct i2c_client *client = capdev->client;
+ struct device *dev = &client->dev;
+ struct i2c_msg msg[2];
+ int err;
+
+ if (len > sizeof(capdev->xfer_buf) - 2)
+ return -EINVAL;
+
+ capdev->xfer_buf[0] = reg;
+ capdev->xfer_buf[1] = len;
+
+ msg[0].addr = client->addr;
+ msg[0].flags = 0;
+ msg[0].buf = capdev->xfer_buf;
+ msg[0].len = 2;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = I2C_M_RD;
+ msg[1].buf = capdev->xfer_buf;
+ msg[1].len = len + 2;
+
+ err = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (err != ARRAY_SIZE(msg))
+ return err < 0 ? err : -EIO;
+
+ if (capdev->xfer_buf[0] != reg) {
+ dev_err(dev, "I2C read error: register address does not match\n");
+ return -ECOMM;
+ }
+
+ memcpy(data, &capdev->xfer_buf[2], len);
+
+ return 0;
+}
+
+/*
+ * Handle interrupt and report the key changes to the input system.
+ * Multi-touch can be supported; however, it really depends on whether
+ * the device can multi-touch.
+ */
+static irqreturn_t atmel_captouch_isr(int irq, void *data)
+{
+ struct atmel_captouch_device *capdev = data;
+ struct device *dev = &capdev->client->dev;
+ int error;
+ int i;
+ u8 new_btn;
+ u8 changed_btn;
+
+ error = atmel_read(capdev, REG_KEY_STATE, &new_btn, 1);
+ if (error) {
+ dev_err(dev, "failed to read button state: %d\n", error);
+ goto out;
+ }
+
+ dev_dbg(dev, "%s: button state %#02x\n", __func__, new_btn);
+
+ changed_btn = new_btn ^ capdev->prev_btn;
+ capdev->prev_btn = new_btn;
+
+ for (i = 0; i < capdev->num_btn; i++) {
+ if (changed_btn & BIT(i))
+ input_report_key(capdev->input,
+ capdev->keycodes[i],
+ new_btn & BIT(i));
+ }
+
+ input_sync(capdev->input);
+
+out:
+ return IRQ_HANDLED;
+}
+
+/*
+ * Probe function to setup the device, input system and interrupt
+ */
+static int atmel_captouch_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct atmel_captouch_device *capdev;
+ struct device *dev = &client->dev;
+ struct device_node *node;
+ int i;
+ int err;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK)) {
+ dev_err(dev, "needed i2c functionality is not supported\n");
+ return -EINVAL;
+ }
+
+ capdev = devm_kzalloc(dev, sizeof(*capdev), GFP_KERNEL);
+ if (!capdev)
+ return -ENOMEM;
+
+ capdev->client = client;
+ i2c_set_clientdata(client, capdev);
+
+ err = atmel_read(capdev, REG_KEY_STATE,
+ &capdev->prev_btn, sizeof(capdev->prev_btn));
+ if (err) {
+ dev_err(dev, "failed to read initial button state: %d\n", err);
+ return err;
+ }
+
+ capdev->input = devm_input_allocate_device(dev);
+ if (!capdev->input) {
+ dev_err(dev, "failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ capdev->input->id.bustype = BUS_I2C;
+ capdev->input->id.product = 0x880A;
+ capdev->input->id.version = 0;
+ capdev->input->name = "ATMegaXX Capacitive Button Controller";
+ __set_bit(EV_KEY, capdev->input->evbit);
+
+ node = dev->of_node;
+ if (!node) {
+ dev_err(dev, "failed to find matching node in device tree\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_bool(node, "autorepeat"))
+ __set_bit(EV_REP, capdev->input->evbit);
+
+ capdev->num_btn = of_property_count_u32_elems(node, "linux,keymap");
+ if (capdev->num_btn > MAX_NUM_OF_BUTTONS)
+ capdev->num_btn = MAX_NUM_OF_BUTTONS;
+
+ err = of_property_read_u32_array(node, "linux,keycodes",
+ capdev->keycodes,
+ capdev->num_btn);
+ if (err) {
+ dev_err(dev,
+ "failed to read linux,keycode property: %d\n", err);
+ return err;
+ }
+
+ for (i = 0; i < capdev->num_btn; i++)
+ __set_bit(capdev->keycodes[i], capdev->input->keybit);
+
+ capdev->input->keycode = capdev->keycodes;
+ capdev->input->keycodesize = sizeof(capdev->keycodes[0]);
+ capdev->input->keycodemax = capdev->num_btn;
+
+ err = input_register_device(capdev->input);
+ if (err)
+ return err;
+
+ err = devm_request_threaded_irq(dev, client->irq, NULL,
+ atmel_captouch_isr, IRQF_ONESHOT,
+ "atmel_captouch", capdev);
+ if (err) {
+ dev_err(dev, "failed to request irq %d: %d\n",
+ client->irq, err);
+ return err;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id atmel_captouch_of_id[] = {
+ {
+ .compatible = "atmel,captouch",
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, atmel_captouch_of_id);
+#endif
+
+static const struct i2c_device_id atmel_captouch_id[] = {
+ { "atmel_captouch", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, atmel_captouch_id);
+
+static struct i2c_driver atmel_captouch_driver = {
+ .probe = atmel_captouch_probe,
+ .id_table = atmel_captouch_id,
+ .driver = {
+ .name = "atmel_captouch",
+ .of_match_table = of_match_ptr(atmel_captouch_of_id),
+ },
+};
+module_i2c_driver(atmel_captouch_driver);
+
+/* Module information */
+MODULE_AUTHOR("Hung-yu Wu <hywu@google.com>");
+MODULE_DESCRIPTION("Atmel ATmegaXX Capacitance Touch Sensor I2C Driver");
+MODULE_LICENSE("GPL v2");
--
2.1.2
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2 V4] Input: add Atmel Captouch Button driver
2016-05-17 19:29 [PATCH 2/2 V4] Input: add Atmel Captouch Button driver Grant Grundler
@ 2016-05-18 21:59 ` Dmitry Torokhov
2016-05-18 22:17 ` Grant Grundler
0 siblings, 1 reply; 4+ messages in thread
From: Dmitry Torokhov @ 2016-05-18 21:59 UTC (permalink / raw)
To: Grant Grundler
Cc: Rob Herring, Pawel Moll, Mark Rutland, devicetree, linux-input,
LKML, Hung-yu Wu, Kumar Gala, Ian Campbell, Grant Likely
On Tue, May 17, 2016 at 12:29:32PM -0700, Grant Grundler wrote:
> From: Daniel Hung-yu Wu <hywu@google.com>
>
> Add I2C driver for Atmel Capacitive Touch Button device.
>
> Signed-off-by: Hung-yu Wu <hywu@google.com>
> Signed-off-by: Grant Grundler <grundler@chromium.org>
Applied, thank you.
> ---
> drivers/input/misc/Kconfig | 13 ++
> drivers/input/misc/Makefile | 1 +
> drivers/input/misc/atmel_captouch.c | 287 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 299 insertions(+)
> create mode 100644 drivers/input/misc/atmel_captouch.c
>
> V4: wordsmithing comments at top of file.
> Added missing semicolon to CONFIG_OF data struct.
>
> V3: use dash, not underscore in nodename. Wordsmith Kconfig help text.
>
> V2: split Documentation/devicetree/bindings from driver patch.
> rename "atmel,atmegaxx_captouch" to "atmel,captouch" since it's irrelevant
> which controller implements the register set/controller.
>
> V1: posted https://lkml.org/lkml/2016/5/3/613
>
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 838824b..d8b6620 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -82,6 +82,19 @@ config INPUT_ARIZONA_HAPTICS
> To compile this driver as a module, choose M here: the
> module will be called arizona-haptics.
>
> +config INPUT_ATMEL_CAPTOUCH
> + tristate "Atmel Capacitive Touch Button Driver"
> + depends on OF || COMPILE_TEST
> + help
> + Say Y here if an Atmel Capacitive Touch Button device which
> + implements "captouch" protocol is connected to I2C bus. Typically
> + this device consists of Atmel Touch sensor controlled by AtMegaXX
> + MCU running firmware based on Qtouch library.
> + One should find "atmel,captouch" node in the board specific DTS.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called atmel_captouch.
> +
> config INPUT_BMA150
> tristate "BMA150/SMB380 acceleration sensor support"
> depends on I2C
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index f77268e..b5ec626 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -17,6 +17,7 @@ obj-$(CONFIG_INPUT_APANEL) += apanel.o
> obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o
> obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o
> obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o
> +obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o
> obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o
> obj-$(CONFIG_INPUT_BMA150) += bma150.o
> obj-$(CONFIG_INPUT_CM109) += cm109.o
> diff --git a/drivers/input/misc/atmel_captouch.c b/drivers/input/misc/atmel_captouch.c
> new file mode 100644
> index 0000000..91bfc73
> --- /dev/null
> +++ b/drivers/input/misc/atmel_captouch.c
> @@ -0,0 +1,287 @@
> +/*
> + * Atmel Capacitive Touch Button Driver
> + *
> + * Copyright (C) 2016 Google, inc.
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * 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.
> + */
> +
> +/*
> + * It's irrelevant the HW used to develop captouch driver is based
> + * on Atmega88PA part and uses QtouchADC parts for sensing touch.
> + * Calling this driver "captouch" is an arbitrary way to distinguish
> + * the protocol this driver supports from other atmel/qtouch drivers.
> + *
> + * captouch driver supports a newer/different version of the I2C
> + * registers/commands than the qt1070.c driver.
> + * Don't let the similarity of the general driver structure fool you. :)
> + *
> + * For raw i2c access from userspace, use i2cset/i2cget
> + * to poke at /dev/i2c-N devices.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/i2c.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/slab.h>
> +
> +/* Maximum number of buttons supported */
> +#define MAX_NUM_OF_BUTTONS 8
> +
> +/* Registers */
> +#define REG_KEY1_THRESHOLD 0x02
> +#define REG_KEY2_THRESHOLD 0x03
> +#define REG_KEY3_THRESHOLD 0x04
> +#define REG_KEY4_THRESHOLD 0x05
> +
> +#define REG_KEY1_REF_H 0x20
> +#define REG_KEY1_REF_L 0x21
> +#define REG_KEY2_REF_H 0x22
> +#define REG_KEY2_REF_L 0x23
> +#define REG_KEY3_REF_H 0x24
> +#define REG_KEY3_REF_L 0x25
> +#define REG_KEY4_REF_H 0x26
> +#define REG_KEY4_REF_L 0x27
> +
> +#define REG_KEY1_DLT_H 0x30
> +#define REG_KEY1_DLT_L 0x31
> +#define REG_KEY2_DLT_H 0x32
> +#define REG_KEY2_DLT_L 0x33
> +#define REG_KEY3_DLT_H 0x34
> +#define REG_KEY3_DLT_L 0x35
> +#define REG_KEY4_DLT_H 0x36
> +#define REG_KEY4_DLT_L 0x37
> +
> +#define REG_KEY_STATE 0x3C
> +
> +/*
> + * @i2c_client: I2C slave device client pointer
> + * @input: Input device pointer
> + * @num_btn: Number of buttons
> + * @keycodes: map of button# to KeyCode
> + * @prev_btn: Previous key state to detect button "press" or "release"
> + * @xfer_buf: I2C transfer buffer
> + */
> +struct atmel_captouch_device {
> + struct i2c_client *client;
> + struct input_dev *input;
> + u32 num_btn;
> + u32 keycodes[MAX_NUM_OF_BUTTONS];
> + u8 prev_btn;
> + u8 xfer_buf[8] ____cacheline_aligned;
> +};
> +
> +/*
> + * Read from I2C slave device
> + * The protocol is that the client has to provide both the register address
> + * and the length, and while reading back the device would prepend the data
> + * with address and length for verification.
> + */
> +static int atmel_read(struct atmel_captouch_device *capdev,
> + u8 reg, u8 *data, size_t len)
> +{
> + struct i2c_client *client = capdev->client;
> + struct device *dev = &client->dev;
> + struct i2c_msg msg[2];
> + int err;
> +
> + if (len > sizeof(capdev->xfer_buf) - 2)
> + return -EINVAL;
> +
> + capdev->xfer_buf[0] = reg;
> + capdev->xfer_buf[1] = len;
> +
> + msg[0].addr = client->addr;
> + msg[0].flags = 0;
> + msg[0].buf = capdev->xfer_buf;
> + msg[0].len = 2;
> +
> + msg[1].addr = client->addr;
> + msg[1].flags = I2C_M_RD;
> + msg[1].buf = capdev->xfer_buf;
> + msg[1].len = len + 2;
> +
> + err = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
> + if (err != ARRAY_SIZE(msg))
> + return err < 0 ? err : -EIO;
> +
> + if (capdev->xfer_buf[0] != reg) {
> + dev_err(dev, "I2C read error: register address does not match\n");
> + return -ECOMM;
> + }
> +
> + memcpy(data, &capdev->xfer_buf[2], len);
> +
> + return 0;
> +}
> +
> +/*
> + * Handle interrupt and report the key changes to the input system.
> + * Multi-touch can be supported; however, it really depends on whether
> + * the device can multi-touch.
> + */
> +static irqreturn_t atmel_captouch_isr(int irq, void *data)
> +{
> + struct atmel_captouch_device *capdev = data;
> + struct device *dev = &capdev->client->dev;
> + int error;
> + int i;
> + u8 new_btn;
> + u8 changed_btn;
> +
> + error = atmel_read(capdev, REG_KEY_STATE, &new_btn, 1);
> + if (error) {
> + dev_err(dev, "failed to read button state: %d\n", error);
> + goto out;
> + }
> +
> + dev_dbg(dev, "%s: button state %#02x\n", __func__, new_btn);
> +
> + changed_btn = new_btn ^ capdev->prev_btn;
> + capdev->prev_btn = new_btn;
> +
> + for (i = 0; i < capdev->num_btn; i++) {
> + if (changed_btn & BIT(i))
> + input_report_key(capdev->input,
> + capdev->keycodes[i],
> + new_btn & BIT(i));
> + }
> +
> + input_sync(capdev->input);
> +
> +out:
> + return IRQ_HANDLED;
> +}
> +
> +/*
> + * Probe function to setup the device, input system and interrupt
> + */
> +static int atmel_captouch_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct atmel_captouch_device *capdev;
> + struct device *dev = &client->dev;
> + struct device_node *node;
> + int i;
> + int err;
> +
> + if (!i2c_check_functionality(client->adapter,
> + I2C_FUNC_SMBUS_BYTE_DATA |
> + I2C_FUNC_SMBUS_WORD_DATA |
> + I2C_FUNC_SMBUS_I2C_BLOCK)) {
> + dev_err(dev, "needed i2c functionality is not supported\n");
> + return -EINVAL;
> + }
> +
> + capdev = devm_kzalloc(dev, sizeof(*capdev), GFP_KERNEL);
> + if (!capdev)
> + return -ENOMEM;
> +
> + capdev->client = client;
> + i2c_set_clientdata(client, capdev);
> +
> + err = atmel_read(capdev, REG_KEY_STATE,
> + &capdev->prev_btn, sizeof(capdev->prev_btn));
> + if (err) {
> + dev_err(dev, "failed to read initial button state: %d\n", err);
> + return err;
> + }
> +
> + capdev->input = devm_input_allocate_device(dev);
> + if (!capdev->input) {
> + dev_err(dev, "failed to allocate input device\n");
> + return -ENOMEM;
> + }
> +
> + capdev->input->id.bustype = BUS_I2C;
> + capdev->input->id.product = 0x880A;
> + capdev->input->id.version = 0;
> + capdev->input->name = "ATMegaXX Capacitive Button Controller";
> + __set_bit(EV_KEY, capdev->input->evbit);
> +
> + node = dev->of_node;
> + if (!node) {
> + dev_err(dev, "failed to find matching node in device tree\n");
> + return -EINVAL;
> + }
> +
> + if (of_property_read_bool(node, "autorepeat"))
> + __set_bit(EV_REP, capdev->input->evbit);
> +
> + capdev->num_btn = of_property_count_u32_elems(node, "linux,keymap");
> + if (capdev->num_btn > MAX_NUM_OF_BUTTONS)
> + capdev->num_btn = MAX_NUM_OF_BUTTONS;
> +
> + err = of_property_read_u32_array(node, "linux,keycodes",
> + capdev->keycodes,
> + capdev->num_btn);
> + if (err) {
> + dev_err(dev,
> + "failed to read linux,keycode property: %d\n", err);
> + return err;
> + }
> +
> + for (i = 0; i < capdev->num_btn; i++)
> + __set_bit(capdev->keycodes[i], capdev->input->keybit);
> +
> + capdev->input->keycode = capdev->keycodes;
> + capdev->input->keycodesize = sizeof(capdev->keycodes[0]);
> + capdev->input->keycodemax = capdev->num_btn;
> +
> + err = input_register_device(capdev->input);
> + if (err)
> + return err;
> +
> + err = devm_request_threaded_irq(dev, client->irq, NULL,
> + atmel_captouch_isr, IRQF_ONESHOT,
> + "atmel_captouch", capdev);
> + if (err) {
> + dev_err(dev, "failed to request irq %d: %d\n",
> + client->irq, err);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_OF
> +static const struct of_device_id atmel_captouch_of_id[] = {
> + {
> + .compatible = "atmel,captouch",
> + },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, atmel_captouch_of_id);
> +#endif
> +
> +static const struct i2c_device_id atmel_captouch_id[] = {
> + { "atmel_captouch", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, atmel_captouch_id);
> +
> +static struct i2c_driver atmel_captouch_driver = {
> + .probe = atmel_captouch_probe,
> + .id_table = atmel_captouch_id,
> + .driver = {
> + .name = "atmel_captouch",
> + .of_match_table = of_match_ptr(atmel_captouch_of_id),
> + },
> +};
> +module_i2c_driver(atmel_captouch_driver);
> +
> +/* Module information */
> +MODULE_AUTHOR("Hung-yu Wu <hywu@google.com>");
> +MODULE_DESCRIPTION("Atmel ATmegaXX Capacitance Touch Sensor I2C Driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.1.2
>
--
Dmitry
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2 V4] Input: add Atmel Captouch Button driver
2016-05-18 21:59 ` Dmitry Torokhov
@ 2016-05-18 22:17 ` Grant Grundler
0 siblings, 0 replies; 4+ messages in thread
From: Grant Grundler @ 2016-05-18 22:17 UTC (permalink / raw)
To: Dmitry Torokhov
Cc: Grant Grundler, Rob Herring, Pawel Moll, Mark Rutland,
devicetree, linux-input, LKML, Hung-yu Wu, Kumar Gala,
Ian Campbell, Grant Likely
On Wed, May 18, 2016 at 2:59 PM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> On Tue, May 17, 2016 at 12:29:32PM -0700, Grant Grundler wrote:
>> From: Daniel Hung-yu Wu <hywu@google.com>
>>
>> Add I2C driver for Atmel Capacitive Touch Button device.
>>
>> Signed-off-by: Hung-yu Wu <hywu@google.com>
>> Signed-off-by: Grant Grundler <grundler@chromium.org>
>
> Applied, thank you.
Awesome! Thanks for your help Dmitry! :)
grant
>
>> ---
>> drivers/input/misc/Kconfig | 13 ++
>> drivers/input/misc/Makefile | 1 +
>> drivers/input/misc/atmel_captouch.c | 287 ++++++++++++++++++++++++++++++++++++
>> 3 files changed, 299 insertions(+)
>> create mode 100644 drivers/input/misc/atmel_captouch.c
>>
>> V4: wordsmithing comments at top of file.
>> Added missing semicolon to CONFIG_OF data struct.
>>
>> V3: use dash, not underscore in nodename. Wordsmith Kconfig help text.
>>
>> V2: split Documentation/devicetree/bindings from driver patch.
>> rename "atmel,atmegaxx_captouch" to "atmel,captouch" since it's irrelevant
>> which controller implements the register set/controller.
>>
>> V1: posted https://lkml.org/lkml/2016/5/3/613
>>
>> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
>> index 838824b..d8b6620 100644
>> --- a/drivers/input/misc/Kconfig
>> +++ b/drivers/input/misc/Kconfig
>> @@ -82,6 +82,19 @@ config INPUT_ARIZONA_HAPTICS
>> To compile this driver as a module, choose M here: the
>> module will be called arizona-haptics.
>>
>> +config INPUT_ATMEL_CAPTOUCH
>> + tristate "Atmel Capacitive Touch Button Driver"
>> + depends on OF || COMPILE_TEST
>> + help
>> + Say Y here if an Atmel Capacitive Touch Button device which
>> + implements "captouch" protocol is connected to I2C bus. Typically
>> + this device consists of Atmel Touch sensor controlled by AtMegaXX
>> + MCU running firmware based on Qtouch library.
>> + One should find "atmel,captouch" node in the board specific DTS.
>> +
>> + To compile this driver as a module, choose M here: the
>> + module will be called atmel_captouch.
>> +
>> config INPUT_BMA150
>> tristate "BMA150/SMB380 acceleration sensor support"
>> depends on I2C
>> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
>> index f77268e..b5ec626 100644
>> --- a/drivers/input/misc/Makefile
>> +++ b/drivers/input/misc/Makefile
>> @@ -17,6 +17,7 @@ obj-$(CONFIG_INPUT_APANEL) += apanel.o
>> obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o
>> obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o
>> obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o
>> +obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o
>> obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o
>> obj-$(CONFIG_INPUT_BMA150) += bma150.o
>> obj-$(CONFIG_INPUT_CM109) += cm109.o
>> diff --git a/drivers/input/misc/atmel_captouch.c b/drivers/input/misc/atmel_captouch.c
>> new file mode 100644
>> index 0000000..91bfc73
>> --- /dev/null
>> +++ b/drivers/input/misc/atmel_captouch.c
>> @@ -0,0 +1,287 @@
>> +/*
>> + * Atmel Capacitive Touch Button Driver
>> + *
>> + * Copyright (C) 2016 Google, inc.
>> + *
>> + * This software is licensed under the terms of the GNU General Public
>> + * License version 2, as published by the Free Software Foundation, and
>> + * may be copied, distributed, and modified under those terms.
>> + *
>> + * 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.
>> + */
>> +
>> +/*
>> + * It's irrelevant the HW used to develop captouch driver is based
>> + * on Atmega88PA part and uses QtouchADC parts for sensing touch.
>> + * Calling this driver "captouch" is an arbitrary way to distinguish
>> + * the protocol this driver supports from other atmel/qtouch drivers.
>> + *
>> + * captouch driver supports a newer/different version of the I2C
>> + * registers/commands than the qt1070.c driver.
>> + * Don't let the similarity of the general driver structure fool you. :)
>> + *
>> + * For raw i2c access from userspace, use i2cset/i2cget
>> + * to poke at /dev/i2c-N devices.
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/input.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/slab.h>
>> +
>> +/* Maximum number of buttons supported */
>> +#define MAX_NUM_OF_BUTTONS 8
>> +
>> +/* Registers */
>> +#define REG_KEY1_THRESHOLD 0x02
>> +#define REG_KEY2_THRESHOLD 0x03
>> +#define REG_KEY3_THRESHOLD 0x04
>> +#define REG_KEY4_THRESHOLD 0x05
>> +
>> +#define REG_KEY1_REF_H 0x20
>> +#define REG_KEY1_REF_L 0x21
>> +#define REG_KEY2_REF_H 0x22
>> +#define REG_KEY2_REF_L 0x23
>> +#define REG_KEY3_REF_H 0x24
>> +#define REG_KEY3_REF_L 0x25
>> +#define REG_KEY4_REF_H 0x26
>> +#define REG_KEY4_REF_L 0x27
>> +
>> +#define REG_KEY1_DLT_H 0x30
>> +#define REG_KEY1_DLT_L 0x31
>> +#define REG_KEY2_DLT_H 0x32
>> +#define REG_KEY2_DLT_L 0x33
>> +#define REG_KEY3_DLT_H 0x34
>> +#define REG_KEY3_DLT_L 0x35
>> +#define REG_KEY4_DLT_H 0x36
>> +#define REG_KEY4_DLT_L 0x37
>> +
>> +#define REG_KEY_STATE 0x3C
>> +
>> +/*
>> + * @i2c_client: I2C slave device client pointer
>> + * @input: Input device pointer
>> + * @num_btn: Number of buttons
>> + * @keycodes: map of button# to KeyCode
>> + * @prev_btn: Previous key state to detect button "press" or "release"
>> + * @xfer_buf: I2C transfer buffer
>> + */
>> +struct atmel_captouch_device {
>> + struct i2c_client *client;
>> + struct input_dev *input;
>> + u32 num_btn;
>> + u32 keycodes[MAX_NUM_OF_BUTTONS];
>> + u8 prev_btn;
>> + u8 xfer_buf[8] ____cacheline_aligned;
>> +};
>> +
>> +/*
>> + * Read from I2C slave device
>> + * The protocol is that the client has to provide both the register address
>> + * and the length, and while reading back the device would prepend the data
>> + * with address and length for verification.
>> + */
>> +static int atmel_read(struct atmel_captouch_device *capdev,
>> + u8 reg, u8 *data, size_t len)
>> +{
>> + struct i2c_client *client = capdev->client;
>> + struct device *dev = &client->dev;
>> + struct i2c_msg msg[2];
>> + int err;
>> +
>> + if (len > sizeof(capdev->xfer_buf) - 2)
>> + return -EINVAL;
>> +
>> + capdev->xfer_buf[0] = reg;
>> + capdev->xfer_buf[1] = len;
>> +
>> + msg[0].addr = client->addr;
>> + msg[0].flags = 0;
>> + msg[0].buf = capdev->xfer_buf;
>> + msg[0].len = 2;
>> +
>> + msg[1].addr = client->addr;
>> + msg[1].flags = I2C_M_RD;
>> + msg[1].buf = capdev->xfer_buf;
>> + msg[1].len = len + 2;
>> +
>> + err = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
>> + if (err != ARRAY_SIZE(msg))
>> + return err < 0 ? err : -EIO;
>> +
>> + if (capdev->xfer_buf[0] != reg) {
>> + dev_err(dev, "I2C read error: register address does not match\n");
>> + return -ECOMM;
>> + }
>> +
>> + memcpy(data, &capdev->xfer_buf[2], len);
>> +
>> + return 0;
>> +}
>> +
>> +/*
>> + * Handle interrupt and report the key changes to the input system.
>> + * Multi-touch can be supported; however, it really depends on whether
>> + * the device can multi-touch.
>> + */
>> +static irqreturn_t atmel_captouch_isr(int irq, void *data)
>> +{
>> + struct atmel_captouch_device *capdev = data;
>> + struct device *dev = &capdev->client->dev;
>> + int error;
>> + int i;
>> + u8 new_btn;
>> + u8 changed_btn;
>> +
>> + error = atmel_read(capdev, REG_KEY_STATE, &new_btn, 1);
>> + if (error) {
>> + dev_err(dev, "failed to read button state: %d\n", error);
>> + goto out;
>> + }
>> +
>> + dev_dbg(dev, "%s: button state %#02x\n", __func__, new_btn);
>> +
>> + changed_btn = new_btn ^ capdev->prev_btn;
>> + capdev->prev_btn = new_btn;
>> +
>> + for (i = 0; i < capdev->num_btn; i++) {
>> + if (changed_btn & BIT(i))
>> + input_report_key(capdev->input,
>> + capdev->keycodes[i],
>> + new_btn & BIT(i));
>> + }
>> +
>> + input_sync(capdev->input);
>> +
>> +out:
>> + return IRQ_HANDLED;
>> +}
>> +
>> +/*
>> + * Probe function to setup the device, input system and interrupt
>> + */
>> +static int atmel_captouch_probe(struct i2c_client *client,
>> + const struct i2c_device_id *id)
>> +{
>> + struct atmel_captouch_device *capdev;
>> + struct device *dev = &client->dev;
>> + struct device_node *node;
>> + int i;
>> + int err;
>> +
>> + if (!i2c_check_functionality(client->adapter,
>> + I2C_FUNC_SMBUS_BYTE_DATA |
>> + I2C_FUNC_SMBUS_WORD_DATA |
>> + I2C_FUNC_SMBUS_I2C_BLOCK)) {
>> + dev_err(dev, "needed i2c functionality is not supported\n");
>> + return -EINVAL;
>> + }
>> +
>> + capdev = devm_kzalloc(dev, sizeof(*capdev), GFP_KERNEL);
>> + if (!capdev)
>> + return -ENOMEM;
>> +
>> + capdev->client = client;
>> + i2c_set_clientdata(client, capdev);
>> +
>> + err = atmel_read(capdev, REG_KEY_STATE,
>> + &capdev->prev_btn, sizeof(capdev->prev_btn));
>> + if (err) {
>> + dev_err(dev, "failed to read initial button state: %d\n", err);
>> + return err;
>> + }
>> +
>> + capdev->input = devm_input_allocate_device(dev);
>> + if (!capdev->input) {
>> + dev_err(dev, "failed to allocate input device\n");
>> + return -ENOMEM;
>> + }
>> +
>> + capdev->input->id.bustype = BUS_I2C;
>> + capdev->input->id.product = 0x880A;
>> + capdev->input->id.version = 0;
>> + capdev->input->name = "ATMegaXX Capacitive Button Controller";
>> + __set_bit(EV_KEY, capdev->input->evbit);
>> +
>> + node = dev->of_node;
>> + if (!node) {
>> + dev_err(dev, "failed to find matching node in device tree\n");
>> + return -EINVAL;
>> + }
>> +
>> + if (of_property_read_bool(node, "autorepeat"))
>> + __set_bit(EV_REP, capdev->input->evbit);
>> +
>> + capdev->num_btn = of_property_count_u32_elems(node, "linux,keymap");
>> + if (capdev->num_btn > MAX_NUM_OF_BUTTONS)
>> + capdev->num_btn = MAX_NUM_OF_BUTTONS;
>> +
>> + err = of_property_read_u32_array(node, "linux,keycodes",
>> + capdev->keycodes,
>> + capdev->num_btn);
>> + if (err) {
>> + dev_err(dev,
>> + "failed to read linux,keycode property: %d\n", err);
>> + return err;
>> + }
>> +
>> + for (i = 0; i < capdev->num_btn; i++)
>> + __set_bit(capdev->keycodes[i], capdev->input->keybit);
>> +
>> + capdev->input->keycode = capdev->keycodes;
>> + capdev->input->keycodesize = sizeof(capdev->keycodes[0]);
>> + capdev->input->keycodemax = capdev->num_btn;
>> +
>> + err = input_register_device(capdev->input);
>> + if (err)
>> + return err;
>> +
>> + err = devm_request_threaded_irq(dev, client->irq, NULL,
>> + atmel_captouch_isr, IRQF_ONESHOT,
>> + "atmel_captouch", capdev);
>> + if (err) {
>> + dev_err(dev, "failed to request irq %d: %d\n",
>> + client->irq, err);
>> + return err;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id atmel_captouch_of_id[] = {
>> + {
>> + .compatible = "atmel,captouch",
>> + },
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, atmel_captouch_of_id);
>> +#endif
>> +
>> +static const struct i2c_device_id atmel_captouch_id[] = {
>> + { "atmel_captouch", 0 },
>> + { }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, atmel_captouch_id);
>> +
>> +static struct i2c_driver atmel_captouch_driver = {
>> + .probe = atmel_captouch_probe,
>> + .id_table = atmel_captouch_id,
>> + .driver = {
>> + .name = "atmel_captouch",
>> + .of_match_table = of_match_ptr(atmel_captouch_of_id),
>> + },
>> +};
>> +module_i2c_driver(atmel_captouch_driver);
>> +
>> +/* Module information */
>> +MODULE_AUTHOR("Hung-yu Wu <hywu@google.com>");
>> +MODULE_DESCRIPTION("Atmel ATmegaXX Capacitance Touch Sensor I2C Driver");
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.1.2
>>
>
> --
> Dmitry
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2 V4] Input: add Atmel Captouch Button driver
@ 2016-05-18 22:17 ` Grant Grundler
0 siblings, 0 replies; 4+ messages in thread
From: Grant Grundler @ 2016-05-18 22:17 UTC (permalink / raw)
To: Dmitry Torokhov
Cc: Grant Grundler, Rob Herring, Pawel Moll, Mark Rutland,
devicetree, linux-input, LKML, Hung-yu Wu, Kumar Gala,
Ian Campbell, Grant Likely
On Wed, May 18, 2016 at 2:59 PM, Dmitry Torokhov
<dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> On Tue, May 17, 2016 at 12:29:32PM -0700, Grant Grundler wrote:
>> From: Daniel Hung-yu Wu <hywu-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
>>
>> Add I2C driver for Atmel Capacitive Touch Button device.
>>
>> Signed-off-by: Hung-yu Wu <hywu-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
>> Signed-off-by: Grant Grundler <grundler-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
>
> Applied, thank you.
Awesome! Thanks for your help Dmitry! :)
grant
>
>> ---
>> drivers/input/misc/Kconfig | 13 ++
>> drivers/input/misc/Makefile | 1 +
>> drivers/input/misc/atmel_captouch.c | 287 ++++++++++++++++++++++++++++++++++++
>> 3 files changed, 299 insertions(+)
>> create mode 100644 drivers/input/misc/atmel_captouch.c
>>
>> V4: wordsmithing comments at top of file.
>> Added missing semicolon to CONFIG_OF data struct.
>>
>> V3: use dash, not underscore in nodename. Wordsmith Kconfig help text.
>>
>> V2: split Documentation/devicetree/bindings from driver patch.
>> rename "atmel,atmegaxx_captouch" to "atmel,captouch" since it's irrelevant
>> which controller implements the register set/controller.
>>
>> V1: posted https://lkml.org/lkml/2016/5/3/613
>>
>> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
>> index 838824b..d8b6620 100644
>> --- a/drivers/input/misc/Kconfig
>> +++ b/drivers/input/misc/Kconfig
>> @@ -82,6 +82,19 @@ config INPUT_ARIZONA_HAPTICS
>> To compile this driver as a module, choose M here: the
>> module will be called arizona-haptics.
>>
>> +config INPUT_ATMEL_CAPTOUCH
>> + tristate "Atmel Capacitive Touch Button Driver"
>> + depends on OF || COMPILE_TEST
>> + help
>> + Say Y here if an Atmel Capacitive Touch Button device which
>> + implements "captouch" protocol is connected to I2C bus. Typically
>> + this device consists of Atmel Touch sensor controlled by AtMegaXX
>> + MCU running firmware based on Qtouch library.
>> + One should find "atmel,captouch" node in the board specific DTS.
>> +
>> + To compile this driver as a module, choose M here: the
>> + module will be called atmel_captouch.
>> +
>> config INPUT_BMA150
>> tristate "BMA150/SMB380 acceleration sensor support"
>> depends on I2C
>> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
>> index f77268e..b5ec626 100644
>> --- a/drivers/input/misc/Makefile
>> +++ b/drivers/input/misc/Makefile
>> @@ -17,6 +17,7 @@ obj-$(CONFIG_INPUT_APANEL) += apanel.o
>> obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o
>> obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o
>> obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o
>> +obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o
>> obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o
>> obj-$(CONFIG_INPUT_BMA150) += bma150.o
>> obj-$(CONFIG_INPUT_CM109) += cm109.o
>> diff --git a/drivers/input/misc/atmel_captouch.c b/drivers/input/misc/atmel_captouch.c
>> new file mode 100644
>> index 0000000..91bfc73
>> --- /dev/null
>> +++ b/drivers/input/misc/atmel_captouch.c
>> @@ -0,0 +1,287 @@
>> +/*
>> + * Atmel Capacitive Touch Button Driver
>> + *
>> + * Copyright (C) 2016 Google, inc.
>> + *
>> + * This software is licensed under the terms of the GNU General Public
>> + * License version 2, as published by the Free Software Foundation, and
>> + * may be copied, distributed, and modified under those terms.
>> + *
>> + * 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.
>> + */
>> +
>> +/*
>> + * It's irrelevant the HW used to develop captouch driver is based
>> + * on Atmega88PA part and uses QtouchADC parts for sensing touch.
>> + * Calling this driver "captouch" is an arbitrary way to distinguish
>> + * the protocol this driver supports from other atmel/qtouch drivers.
>> + *
>> + * captouch driver supports a newer/different version of the I2C
>> + * registers/commands than the qt1070.c driver.
>> + * Don't let the similarity of the general driver structure fool you. :)
>> + *
>> + * For raw i2c access from userspace, use i2cset/i2cget
>> + * to poke at /dev/i2c-N devices.
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/input.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/slab.h>
>> +
>> +/* Maximum number of buttons supported */
>> +#define MAX_NUM_OF_BUTTONS 8
>> +
>> +/* Registers */
>> +#define REG_KEY1_THRESHOLD 0x02
>> +#define REG_KEY2_THRESHOLD 0x03
>> +#define REG_KEY3_THRESHOLD 0x04
>> +#define REG_KEY4_THRESHOLD 0x05
>> +
>> +#define REG_KEY1_REF_H 0x20
>> +#define REG_KEY1_REF_L 0x21
>> +#define REG_KEY2_REF_H 0x22
>> +#define REG_KEY2_REF_L 0x23
>> +#define REG_KEY3_REF_H 0x24
>> +#define REG_KEY3_REF_L 0x25
>> +#define REG_KEY4_REF_H 0x26
>> +#define REG_KEY4_REF_L 0x27
>> +
>> +#define REG_KEY1_DLT_H 0x30
>> +#define REG_KEY1_DLT_L 0x31
>> +#define REG_KEY2_DLT_H 0x32
>> +#define REG_KEY2_DLT_L 0x33
>> +#define REG_KEY3_DLT_H 0x34
>> +#define REG_KEY3_DLT_L 0x35
>> +#define REG_KEY4_DLT_H 0x36
>> +#define REG_KEY4_DLT_L 0x37
>> +
>> +#define REG_KEY_STATE 0x3C
>> +
>> +/*
>> + * @i2c_client: I2C slave device client pointer
>> + * @input: Input device pointer
>> + * @num_btn: Number of buttons
>> + * @keycodes: map of button# to KeyCode
>> + * @prev_btn: Previous key state to detect button "press" or "release"
>> + * @xfer_buf: I2C transfer buffer
>> + */
>> +struct atmel_captouch_device {
>> + struct i2c_client *client;
>> + struct input_dev *input;
>> + u32 num_btn;
>> + u32 keycodes[MAX_NUM_OF_BUTTONS];
>> + u8 prev_btn;
>> + u8 xfer_buf[8] ____cacheline_aligned;
>> +};
>> +
>> +/*
>> + * Read from I2C slave device
>> + * The protocol is that the client has to provide both the register address
>> + * and the length, and while reading back the device would prepend the data
>> + * with address and length for verification.
>> + */
>> +static int atmel_read(struct atmel_captouch_device *capdev,
>> + u8 reg, u8 *data, size_t len)
>> +{
>> + struct i2c_client *client = capdev->client;
>> + struct device *dev = &client->dev;
>> + struct i2c_msg msg[2];
>> + int err;
>> +
>> + if (len > sizeof(capdev->xfer_buf) - 2)
>> + return -EINVAL;
>> +
>> + capdev->xfer_buf[0] = reg;
>> + capdev->xfer_buf[1] = len;
>> +
>> + msg[0].addr = client->addr;
>> + msg[0].flags = 0;
>> + msg[0].buf = capdev->xfer_buf;
>> + msg[0].len = 2;
>> +
>> + msg[1].addr = client->addr;
>> + msg[1].flags = I2C_M_RD;
>> + msg[1].buf = capdev->xfer_buf;
>> + msg[1].len = len + 2;
>> +
>> + err = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
>> + if (err != ARRAY_SIZE(msg))
>> + return err < 0 ? err : -EIO;
>> +
>> + if (capdev->xfer_buf[0] != reg) {
>> + dev_err(dev, "I2C read error: register address does not match\n");
>> + return -ECOMM;
>> + }
>> +
>> + memcpy(data, &capdev->xfer_buf[2], len);
>> +
>> + return 0;
>> +}
>> +
>> +/*
>> + * Handle interrupt and report the key changes to the input system.
>> + * Multi-touch can be supported; however, it really depends on whether
>> + * the device can multi-touch.
>> + */
>> +static irqreturn_t atmel_captouch_isr(int irq, void *data)
>> +{
>> + struct atmel_captouch_device *capdev = data;
>> + struct device *dev = &capdev->client->dev;
>> + int error;
>> + int i;
>> + u8 new_btn;
>> + u8 changed_btn;
>> +
>> + error = atmel_read(capdev, REG_KEY_STATE, &new_btn, 1);
>> + if (error) {
>> + dev_err(dev, "failed to read button state: %d\n", error);
>> + goto out;
>> + }
>> +
>> + dev_dbg(dev, "%s: button state %#02x\n", __func__, new_btn);
>> +
>> + changed_btn = new_btn ^ capdev->prev_btn;
>> + capdev->prev_btn = new_btn;
>> +
>> + for (i = 0; i < capdev->num_btn; i++) {
>> + if (changed_btn & BIT(i))
>> + input_report_key(capdev->input,
>> + capdev->keycodes[i],
>> + new_btn & BIT(i));
>> + }
>> +
>> + input_sync(capdev->input);
>> +
>> +out:
>> + return IRQ_HANDLED;
>> +}
>> +
>> +/*
>> + * Probe function to setup the device, input system and interrupt
>> + */
>> +static int atmel_captouch_probe(struct i2c_client *client,
>> + const struct i2c_device_id *id)
>> +{
>> + struct atmel_captouch_device *capdev;
>> + struct device *dev = &client->dev;
>> + struct device_node *node;
>> + int i;
>> + int err;
>> +
>> + if (!i2c_check_functionality(client->adapter,
>> + I2C_FUNC_SMBUS_BYTE_DATA |
>> + I2C_FUNC_SMBUS_WORD_DATA |
>> + I2C_FUNC_SMBUS_I2C_BLOCK)) {
>> + dev_err(dev, "needed i2c functionality is not supported\n");
>> + return -EINVAL;
>> + }
>> +
>> + capdev = devm_kzalloc(dev, sizeof(*capdev), GFP_KERNEL);
>> + if (!capdev)
>> + return -ENOMEM;
>> +
>> + capdev->client = client;
>> + i2c_set_clientdata(client, capdev);
>> +
>> + err = atmel_read(capdev, REG_KEY_STATE,
>> + &capdev->prev_btn, sizeof(capdev->prev_btn));
>> + if (err) {
>> + dev_err(dev, "failed to read initial button state: %d\n", err);
>> + return err;
>> + }
>> +
>> + capdev->input = devm_input_allocate_device(dev);
>> + if (!capdev->input) {
>> + dev_err(dev, "failed to allocate input device\n");
>> + return -ENOMEM;
>> + }
>> +
>> + capdev->input->id.bustype = BUS_I2C;
>> + capdev->input->id.product = 0x880A;
>> + capdev->input->id.version = 0;
>> + capdev->input->name = "ATMegaXX Capacitive Button Controller";
>> + __set_bit(EV_KEY, capdev->input->evbit);
>> +
>> + node = dev->of_node;
>> + if (!node) {
>> + dev_err(dev, "failed to find matching node in device tree\n");
>> + return -EINVAL;
>> + }
>> +
>> + if (of_property_read_bool(node, "autorepeat"))
>> + __set_bit(EV_REP, capdev->input->evbit);
>> +
>> + capdev->num_btn = of_property_count_u32_elems(node, "linux,keymap");
>> + if (capdev->num_btn > MAX_NUM_OF_BUTTONS)
>> + capdev->num_btn = MAX_NUM_OF_BUTTONS;
>> +
>> + err = of_property_read_u32_array(node, "linux,keycodes",
>> + capdev->keycodes,
>> + capdev->num_btn);
>> + if (err) {
>> + dev_err(dev,
>> + "failed to read linux,keycode property: %d\n", err);
>> + return err;
>> + }
>> +
>> + for (i = 0; i < capdev->num_btn; i++)
>> + __set_bit(capdev->keycodes[i], capdev->input->keybit);
>> +
>> + capdev->input->keycode = capdev->keycodes;
>> + capdev->input->keycodesize = sizeof(capdev->keycodes[0]);
>> + capdev->input->keycodemax = capdev->num_btn;
>> +
>> + err = input_register_device(capdev->input);
>> + if (err)
>> + return err;
>> +
>> + err = devm_request_threaded_irq(dev, client->irq, NULL,
>> + atmel_captouch_isr, IRQF_ONESHOT,
>> + "atmel_captouch", capdev);
>> + if (err) {
>> + dev_err(dev, "failed to request irq %d: %d\n",
>> + client->irq, err);
>> + return err;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id atmel_captouch_of_id[] = {
>> + {
>> + .compatible = "atmel,captouch",
>> + },
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, atmel_captouch_of_id);
>> +#endif
>> +
>> +static const struct i2c_device_id atmel_captouch_id[] = {
>> + { "atmel_captouch", 0 },
>> + { }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, atmel_captouch_id);
>> +
>> +static struct i2c_driver atmel_captouch_driver = {
>> + .probe = atmel_captouch_probe,
>> + .id_table = atmel_captouch_id,
>> + .driver = {
>> + .name = "atmel_captouch",
>> + .of_match_table = of_match_ptr(atmel_captouch_of_id),
>> + },
>> +};
>> +module_i2c_driver(atmel_captouch_driver);
>> +
>> +/* Module information */
>> +MODULE_AUTHOR("Hung-yu Wu <hywu-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>");
>> +MODULE_DESCRIPTION("Atmel ATmegaXX Capacitance Touch Sensor I2C Driver");
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.1.2
>>
>
> --
> Dmitry
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^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-05-18 22:17 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-05-17 19:29 [PATCH 2/2 V4] Input: add Atmel Captouch Button driver Grant Grundler
2016-05-18 21:59 ` Dmitry Torokhov
2016-05-18 22:17 ` Grant Grundler
2016-05-18 22:17 ` Grant Grundler
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