[PATCH v7 2/3] input: tm2-touchkey: Add touchkey driver support for TM2

Jaechul Lee
2017-01-17T05:54:38Z

This patch adds support for the TM2 touch key and led
functionality.

The driver interfaces with userspace through an input device and
reports KEY_PHONE and KEY_BACK event types. LED brightness can be
controlled by "/sys/class/leds/tm2-touchkey/brightness".

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
Signed-off-by: Jaechul Lee <jcsing.lee@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
drivers/input/keyboard/Kconfig | 11 ++
drivers/input/keyboard/Makefile | 1 +
drivers/input/keyboard/tm2-touchkey.c | 286 ++++++++++++++++++++++++++++++++++
3 files changed, 298 insertions(+)
create mode 100644 drivers/input/keyboard/tm2-touchkey.c

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index cbd75cf..97acd65 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -666,6 +666,17 @@ config KEYBOARD_TC3589X
To compile this driver as a module, choose M here: the
module will be called tc3589x-keypad.

+config KEYBOARD_TM2_TOUCHKEY
+ tristate "TM2 touchkey support"
+ depends on I2C
+ depends on LEDS_CLASS
+ help
+ Say Y here to enable device driver for tm2-touchkey with
+ LED control for the Exynos5433 TM2 board.
+
+ To compile this driver as a module, choose M here.
+ module will be called tm2-touchkey.
+
config KEYBOARD_TWL4030
tristate "TI TWL4030/TWL5030/TPS659x0 keypad support"
depends on TWL4030_CORE
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index d9f4cfc..7d9acff 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_KEYBOARD_SUN4I_LRADC) += sun4i-lradc-keys.o
obj-$(CONFIG_KEYBOARD_SUNKBD) += sunkbd.o
obj-$(CONFIG_KEYBOARD_TC3589X) += tc3589x-keypad.o
obj-$(CONFIG_KEYBOARD_TEGRA) += tegra-kbc.o
+obj-$(CONFIG_KEYBOARD_TM2_TOUCHKEY) += tm2-touchkey.o
obj-$(CONFIG_KEYBOARD_TWL4030) += twl4030_keypad.o
obj-$(CONFIG_KEYBOARD_XTKBD) += xtkbd.o
obj-$(CONFIG_KEYBOARD_W90P910) += w90p910_keypad.o
diff --git a/drivers/input/keyboard/tm2-touchkey.c b/drivers/input/keyboard/tm2-touchkey.c
new file mode 100644
index 0000000..916e2f3
--- /dev/null
+++ b/drivers/input/keyboard/tm2-touchkey.c
@@ -0,0 +1,286 @@
+/*
+ * TM2 touchkey device driver
+ *
+ * Copyright 2005 Phil Blundell
+ * Copyright 2016 Samsung Electronics Co., Ltd.
+ *
+ * Author: Beomho Seo <beomho.seo@samsung.com>
+ * Author: Jaechul Lee <jcsing.lee@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#define TM2_TOUCHKEY_DEV_NAME "tm2-touchkey"
+#define TM2_TOUCHKEY_KEYCODE_REG 0x03
+#define TM2_TOUCHKEY_BASE_REG 0x00
+#define TM2_TOUCHKEY_CMD_LED_ON 0x10
+#define TM2_TOUCHKEY_CMD_LED_OFF 0x20
+#define TM2_TOUCHKEY_BIT_PRESS_EV BIT(3)
+#define TM2_TOUCHKEY_BIT_KEYCODE GENMASK(2, 0)
+#define TM2_TOUCHKEY_LED_VOLTAGE_MIN 2500000
+#define TM2_TOUCHKEY_LED_VOLTAGE_MAX 3300000
+
+enum {
+ TM2_TOUCHKEY_KEY_MENU = 0x1,
+ TM2_TOUCHKEY_KEY_BACK,
+};
+
+struct tm2_touchkey_data {
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ struct led_classdev led_dev;
+ struct regulator *vdd;
+ struct regulator_bulk_data regulators[2];
+};
+
+static void tm2_touchkey_led_brightness_set(struct led_classdev *led_dev,
+ enum led_brightness brightness)
+{
+ struct tm2_touchkey_data *touchkey =
+ container_of(led_dev, struct tm2_touchkey_data, led_dev);
+ u32 volt;
+ u8 data;
+
+ if (brightness == LED_OFF) {
+ volt = TM2_TOUCHKEY_LED_VOLTAGE_MIN;
+ data = TM2_TOUCHKEY_CMD_LED_OFF;
+ } else {
+ volt = TM2_TOUCHKEY_LED_VOLTAGE_MAX;
+ data = TM2_TOUCHKEY_CMD_LED_ON;
+ }
+
+ regulator_set_voltage(touchkey->vdd, volt, volt);
+ i2c_smbus_write_byte_data(touchkey->client,
+ TM2_TOUCHKEY_BASE_REG, data);
+}
+
+static int tm2_touchkey_power_enable(struct tm2_touchkey_data *touchkey)
+{
+ int error;
+
+ error = regulator_bulk_enable(ARRAY_SIZE(touchkey->regulators),
+ touchkey->regulators);
+ if (error)
+ return error;
+
+ /* waiting for device initialization, at least 150ms */
+ msleep(150);
+
+ return 0;
+}
+
+static void tm2_touchkey_power_disable(void *data)
+{
+ struct tm2_touchkey_data *touchkey = data;
+
+ regulator_bulk_disable(ARRAY_SIZE(touchkey->regulators),
+ touchkey->regulators);
+}
+
+static irqreturn_t tm2_touchkey_irq_handler(int irq, void *devid)
+{
+ struct tm2_touchkey_data *touchkey = devid;
+ int data;
+ int key;
+
+ data = i2c_smbus_read_byte_data(touchkey->client,
+ TM2_TOUCHKEY_KEYCODE_REG);
+ if (data < 0) {
+ dev_err(&touchkey->client->dev,
+ "failed to read i2c data: %d\n", data);
+ goto out;
+ }
+
+ switch (data & TM2_TOUCHKEY_BIT_KEYCODE) {
+ case TM2_TOUCHKEY_KEY_MENU:
+ key = KEY_PHONE;
+ break;
+
+ case TM2_TOUCHKEY_KEY_BACK:
+ key = KEY_BACK;
+ break;
+
+ default:
+ dev_warn(&touchkey->client->dev,
+ "unhandled keycode, data %#02x\n", data);
+ goto out;
+ }
+
+ if (data & TM2_TOUCHKEY_BIT_PRESS_EV) {
+ input_report_key(touchkey->input_dev, KEY_PHONE, 0);
+ input_report_key(touchkey->input_dev, KEY_BACK, 0);
+ } else {
+ input_report_key(touchkey->input_dev, key, 1);
+ }
+
+ input_sync(touchkey->input_dev);
+
+out:
+ return IRQ_HANDLED;
+}
+
+static int tm2_touchkey_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tm2_touchkey_data *touchkey;
+ int error;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA)) {
+ dev_err(&client->dev, "incompatible I2C adapter\n");
+ return -EIO;
+ }
+
+ touchkey = devm_kzalloc(&client->dev, sizeof(*touchkey), GFP_KERNEL);
+ if (!touchkey)
+ return -ENOMEM;
+
+ touchkey->client = client;
+ i2c_set_clientdata(client, touchkey);
+
+ touchkey->regulators[0].supply = "vcc";
+ touchkey->regulators[1].supply = "vdd";
+ error = devm_regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(touchkey->regulators),
+ touchkey->regulators);
+ if (error) {
+ dev_err(&client->dev, "failed to get regulators: %d\n", error);
+ return error;
+ }
+
+ /* Save VDD for easy access */
+ touchkey->vdd = touchkey->regulators[1].consumer;
+
+ error = tm2_touchkey_power_enable(touchkey);
+ if (error) {
+ dev_err(&client->dev, "failed to power up device: %d\n", error);
+ return error;
+ }
+
+ error = devm_add_action_or_reset(&client->dev,
+ tm2_touchkey_power_disable, touchkey);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to install poweroff handler: %d\n", error);
+ return error;
+ }
+
+ /* input device */
+ touchkey->input_dev = devm_input_allocate_device(&client->dev);
+ if (!touchkey->input_dev) {
+ dev_err(&client->dev, "failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ touchkey->input_dev->name = TM2_TOUCHKEY_DEV_NAME;
+ touchkey->input_dev->id.bustype = BUS_I2C;
+
+ input_set_capability(touchkey->input_dev, EV_KEY, KEY_PHONE);
+ input_set_capability(touchkey->input_dev, EV_KEY, KEY_BACK);
+
+ input_set_drvdata(touchkey->input_dev, touchkey);
+
+ error = input_register_device(touchkey->input_dev);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to register input device: %d\n", error);
+ return error;
+ }
+
+ error = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, tm2_touchkey_irq_handler,
+ IRQF_ONESHOT,
+ TM2_TOUCHKEY_DEV_NAME, touchkey);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to request threaded irq: %d\n", error);
+ return error;
+ }
+
+ /* led device */
+ touchkey->led_dev.name = TM2_TOUCHKEY_DEV_NAME;
+ touchkey->led_dev.brightness = LED_FULL;
+ touchkey->led_dev.max_brightness = LED_FULL;
+ touchkey->led_dev.brightness_set = tm2_touchkey_led_brightness_set;
+
+ error = devm_led_classdev_register(&client->dev, &touchkey->led_dev);
+ if (error) {
+ dev_err(&client->dev,
+ "failed to register touchkey led: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static int __maybe_unused tm2_touchkey_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
+
+ disable_irq(client->irq);
+ tm2_touchkey_power_disable(touchkey);
+
+ return 0;
+}
+
+static int __maybe_unused tm2_touchkey_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tm2_touchkey_data *touchkey = i2c_get_clientdata(client);
+ int ret;
+
+ enable_irq(client->irq);
+
+ ret = tm2_touchkey_power_enable(touchkey);
+ if (ret)
+ dev_err(dev, "failed to enable power: %d\n", ret);
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(tm2_touchkey_pm_ops,
+ tm2_touchkey_suspend, tm2_touchkey_resume);
+
+static const struct i2c_device_id tm2_touchkey_id_table[] = {
+ { TM2_TOUCHKEY_DEV_NAME, 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, tm2_touchkey_id_table);
+
+static const struct of_device_id tm2_touchkey_of_match[] = {
+ { .compatible = "cypress,tm2-touchkey", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, tm2_touchkey_of_match);
+
+static struct i2c_driver tm2_touchkey_driver = {
+ .driver = {
+ .name = TM2_TOUCHKEY_DEV_NAME,
+ .pm = &tm2_touchkey_pm_ops,
+ .of_match_table = of_match_ptr(tm2_touchkey_of_match),
+ },
+ .probe = tm2_touchkey_probe,
+ .id_table = tm2_touchkey_id_table,
+};
+module_i2c_driver(tm2_touchkey_driver);
+
+MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
+MODULE_AUTHOR("Jaechul Lee <jcsing.lee@samsung.com>");
+MODULE_DESCRIPTION("Samsung touchkey driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4