[PATCH 2/4] input: tm2-touchkey: Add touchkey driver support for TM2
Javier Martinez Canillas
javier at osg.samsung.com
Tue Jan 3 05:11:39 PST 2017
Hello Jaechul,
On 01/03/2017 04:57 AM, Jaechul Lee wrote:
> This patch adds support for the TM2 touch key and led
> functionlity.
>
s/functionlity/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: Jaechul Lee <jcsing.lee at samsung.com>
> Signed-off-by: Beomho Seo <beomho.seo at samsung.com>
> ---
> drivers/input/keyboard/Kconfig | 11 ++
> drivers/input/keyboard/Makefile | 1 +
> drivers/input/keyboard/tm2-touchkey.c | 326 ++++++++++++++++++++++++++++++++++
> 3 files changed, 338 insertions(+)
> create mode 100644 drivers/input/keyboard/tm2-touchkey.c
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index cbd75cf..72c0ba1 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
> + help
> + Say Y here to enable the tm2-touchkey.
> + touchkey driver for tm2. This driver can enable
> + the interrupt and make input events and control led brightness.
> +
> + 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..d9575d8
> --- /dev/null
> +++ b/drivers/input/keyboard/tm2-touchkey.c
> @@ -0,0 +1,326 @@
> +/*
> + * Driver for keys on GPIO lines capable of generating interrupts.
> + *
> + * Copyright 2005 Phil Blundell
> + * Copyright 2016 Samsung Electronics Co., Ltd.
> + *
> + * Author: Beomho Seo <beomho.seo at samsung.com>
> + * Author: Jaechul Lee <jcsing.lee at 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>
> +#include <linux/workqueue.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,
> +};
> +
> +#define tm2_touchkey_power_enable(x) __tm2_touchkey_power_onoff(x, 1)
> +#define tm2_touchkey_power_disable(x) __tm2_touchkey_power_onoff(x, 0)
> +
> +struct tm2_touchkey_data {
> + struct i2c_client *client;
> + struct input_dev *input_dev;
> + struct led_classdev led_dev;
> +
> + u8 keycode_type;
> + u8 pressed;
> + struct work_struct irq_work;
> +
> + bool power_onoff;
> + struct regulator *regulator_vcc; /* 1.8V */
> + struct regulator *regulator_vdd; /* 3.3V */
> +};
> +
> +static void tm2_touchkey_led_brightness_set(struct led_classdev *led_dev,
> + enum led_brightness brightness)
> +{
> + struct tm2_touchkey_data *samsung_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(samsung_touchkey->regulator_vdd, volt, volt);
> + i2c_smbus_write_byte_data(samsung_touchkey->client,
> + TM2_TOUCHKEY_BASE_REG, data);
> +}
> +
> +static int __tm2_touchkey_power_onoff(struct tm2_touchkey_data
> + *samsung_touchkey, bool onoff)
> +{
> + int ret = 0;
> +
> + if (samsung_touchkey->power_onoff == onoff)
> + return ret;
> +
> + if (onoff) {
> + ret = regulator_enable(samsung_touchkey->regulator_vcc);
> + if (ret)
> + return ret;
> +
> + ret = regulator_enable(samsung_touchkey->regulator_vdd);
> + if (ret) {
> + regulator_disable(samsung_touchkey->regulator_vcc);
> + return ret;
> + }
I would add a comment about the sleep here.
> + msleep(150);
> + } else {
> + int err;
> +
> + err = regulator_disable(samsung_touchkey->regulator_vcc);
> + if (err)
> + ret = err;
> +
> + err = regulator_disable(samsung_touchkey->regulator_vdd);
> + if (err && !ret)
> + ret = err;
> + }
> + samsung_touchkey->power_onoff = onoff;
> +
> + return ret;
> +}
> +
> +static void tm2_touchkey_irq_work(struct work_struct *irq_work)
> +{
> + struct tm2_touchkey_data *samsung_touchkey =
> + container_of(irq_work, struct tm2_touchkey_data, irq_work);
> +
> + if (!samsung_touchkey->pressed) {
> + input_report_key(samsung_touchkey->input_dev, KEY_PHONE, 0);
> + input_report_key(samsung_touchkey->input_dev, KEY_BACK, 0);
> + } else {
> + if (samsung_touchkey->keycode_type == TM2_TOUCHKEY_KEY_MENU)
> + input_report_key(samsung_touchkey->input_dev,
> + KEY_PHONE, 1);
> + else
> + input_report_key(samsung_touchkey->input_dev,
> + KEY_BACK, 1);
> + }
> + input_sync(samsung_touchkey->input_dev);
> +}
> +
> +static irqreturn_t tm2_touchkey_irq_handler(int irq, void *devid)
> +{
> + struct tm2_touchkey_data *samsung_touchkey = devid;
> + u32 data;
> +
> + data = i2c_smbus_read_byte_data(samsung_touchkey->client,
> + TM2_TOUCHKEY_KEYCODE_REG);
> +
> + if (data < 0) {
> + dev_err(&samsung_touchkey->client->dev, "Failed to read i2c data\n");
> + return IRQ_HANDLED;
> + }
> +
> + samsung_touchkey->keycode_type = data & TM2_TOUCHKEY_BIT_KEYCODE;
> + samsung_touchkey->pressed = !(data & TM2_TOUCHKEY_BIT_PRESS_EV);
> +
> + if (samsung_touchkey->keycode_type != TM2_TOUCHKEY_KEY_MENU &&
> + samsung_touchkey->keycode_type != TM2_TOUCHKEY_KEY_BACK)
Shouldn't at least a debug message be printed here so the user can
know that an error occurred and a correct keycode was not received?
> + return IRQ_HANDLED;
> +
> + schedule_work(&samsung_touchkey->irq_work);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int tm2_touchkey_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct tm2_touchkey_data *samsung_touchkey;
> + int ret;
> +
> + ret = i2c_check_functionality(client->adapter,
> + I2C_FUNC_SMBUS_BYTE |
> + I2C_FUNC_SMBUS_BYTE_DATA);
> + if (!ret) {
> + dev_err(&client->dev, "No I2C functionality found\n");
> + return -ENODEV;
> + }
> +
> + samsung_touchkey = devm_kzalloc(&client->dev,
> + sizeof(struct tm2_touchkey_data), GFP_KERNEL);
> +
> + if (!samsung_touchkey) {
> + dev_err(&client->dev, "Failed to allocate memory.\n");
> + return -ENOMEM;
> + }
> +
> + samsung_touchkey->client = client;
> + i2c_set_clientdata(client, samsung_touchkey);
> + INIT_WORK(&samsung_touchkey->irq_work, tm2_touchkey_irq_work);
> +
> + /* regulator */
> + samsung_touchkey->regulator_vcc =
> + devm_regulator_get(&client->dev, "vcc");
> + if (IS_ERR(samsung_touchkey->regulator_vcc)) {
> + dev_err(&client->dev, "Failed to get vcc regulator\n");
> + return PTR_ERR(samsung_touchkey->regulator_vcc);
> + }
> +
> + samsung_touchkey->regulator_vdd =
> + devm_regulator_get(&client->dev, "vdd");
> + if (IS_ERR(samsung_touchkey->regulator_vdd)) {
> + dev_err(&client->dev, "Failed to get vdd regulator\n");
> + return PTR_ERR(samsung_touchkey->regulator_vcc);
> + }
> +
> + /* power */
> + ret = tm2_touchkey_power_enable(samsung_touchkey);
> + if (ret) {
> + dev_err(&client->dev, "Failed to enable power\n");
> + return ret;
> + }
> +
> + /* irq */
> + ret = devm_request_threaded_irq(&client->dev,
> + client->irq, NULL,
> + tm2_touchkey_irq_handler,
> + IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> + TM2_TOUCHKEY_DEV_NAME,
> + samsung_touchkey);
> + if (ret) {
> + dev_err(&client->dev, "Failed to request threaded irq\n");
> + return ret;
> + }
> +
> + /* input device */
> + samsung_touchkey->input_dev = devm_input_allocate_device(&client->dev);
> + if (!samsung_touchkey->input_dev) {
> + dev_err(&client->dev, "Failed to alloc input device.\n");
> + return -ENOMEM;
> + }
> + samsung_touchkey->input_dev->name = TM2_TOUCHKEY_DEV_NAME;
> + samsung_touchkey->input_dev->id.bustype = BUS_I2C;
> + samsung_touchkey->input_dev->dev.parent = &client->dev;
> +
> + set_bit(EV_KEY, samsung_touchkey->input_dev->evbit);
> + set_bit(KEY_PHONE, samsung_touchkey->input_dev->keybit);
> + set_bit(KEY_BACK, samsung_touchkey->input_dev->keybit);
> + input_set_drvdata(samsung_touchkey->input_dev, samsung_touchkey);
> +
> + ret = input_register_device(samsung_touchkey->input_dev);
> + if (ret) {
> + dev_err(&client->dev, "Failed to register input device.\n");
> + return ret;
> + }
> +
> + /* led device */
> + samsung_touchkey->led_dev.name = TM2_TOUCHKEY_DEV_NAME;
> + samsung_touchkey->led_dev.brightness = LED_FULL;
> + samsung_touchkey->led_dev.max_brightness = LED_FULL;
> + samsung_touchkey->led_dev.brightness_set =
> + tm2_touchkey_led_brightness_set;
> +
> + ret = devm_led_classdev_register(&client->dev,
> + &samsung_touchkey->led_dev);
> + if (ret < 0) {
> + dev_err(&client->dev, "Failed to register touchkey led\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void tm2_touchkey_shutdown(struct i2c_client *client)
> +{
> + struct tm2_touchkey_data *samsung_touchkey =
> + i2c_get_clientdata(client);
> + int ret;
> +
> + disable_irq(client->irq);
> + ret = tm2_touchkey_power_disable(samsung_touchkey);
> + if (ret)
> + dev_err(&client->dev, "Failed to disable power\n");
> +}
> +
> +static int tm2_touchkey_suspend(struct device *dev)
> +{
> + struct tm2_touchkey_data *samsung_touchkey = dev_get_drvdata(dev);
> + int ret;
> +
> + disable_irq(samsung_touchkey->client->irq);
> + ret = tm2_touchkey_power_disable(samsung_touchkey);
> + if (ret)
> + dev_err(dev, "Failed to disable power\n");
> +
> + return ret;
> +}
These two functions are basically the same, can you factor it out?
> +
> +static int tm2_touchkey_resume(struct device *dev)
> +{
> + struct tm2_touchkey_data *samsung_touchkey = dev_get_drvdata(dev);
> + int ret;
> +
> + enable_irq(samsung_touchkey->client->irq);
> + ret = tm2_touchkey_power_enable(samsung_touchkey);
> + if (ret)
> + dev_err(dev, "Failed to enable power\n");
> +
> + 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},
> + {},
> +};
> +
You need a MODULE_DEVICE_TABLE(i2c, tm2_touchkey_id_table) here so the
module can be autoloaded when the device is registered.
> +static const struct of_device_id tm2_touchkey_of_match[] = {
> + {.compatible = "samsung,tm2-touchkey",},
> + {},
> +};
> +
Here a MODULE_DEVICE_TABLE(of, tm2_touchkey_of_match) is not strictly
needed since the I2C core always reports MODALIAS of the form i2c:<dev>
but still is good to have so the I2C core can be fixed at some point.
> +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,
> + .shutdown = tm2_touchkey_shutdown,
> + .id_table = tm2_touchkey_id_table,
> +};
> +
> +module_i2c_driver(tm2_touchkey_driver);
> +
> +MODULE_AUTHOR("Beomho Seo <beomho.seo at samsung.com>");
> +MODULE_AUTHOR("Jaechul Lee <jcsing.lee at samsung.com>");
> +MODULE_DESCRIPTION("Samsung touchkey driver");
> +MODULE_LICENSE("GPL v2");
>
The rest looks good to me, so after the changes I suggested:
Reviewed-by: Javier Martinez Canillas <javier at osg.samsung.com>
Best regards,
--
Javier Martinez Canillas
Open Source Group
Samsung Research America
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