Input: tm2-touchkey - add touchkey driver support for TM2
authorJaechul Lee <jcsing.lee@samsung.com>
Wed, 18 Jan 2017 22:35:42 +0000 (14:35 -0800)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Wed, 18 Jan 2017 22:50:23 +0000 (14:50 -0800)
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>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt [new file with mode: 0644]
drivers/input/keyboard/Kconfig
drivers/input/keyboard/Makefile
drivers/input/keyboard/tm2-touchkey.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt b/Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt
new file mode 100644 (file)
index 0000000..635f62c
--- /dev/null
@@ -0,0 +1,27 @@
+Samsung tm2-touchkey
+
+Required properties:
+- compatible: must be "cypress,tm2-touchkey"
+- reg: I2C address of the chip.
+- interrupt-parent: a phandle for the interrupt controller (see interrupt
+       binding[0]).
+- interrupts: interrupt to which the chip is connected (see interrupt
+       binding[0]).
+- vcc-supply : internal regulator output. 1.8V
+- vdd-supply : power supply for IC 3.3V
+
+[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+Example:
+       &i2c0 {
+               /* ... */
+
+               touchkey@20 {
+                       compatible = "cypress,tm2-touchkey";
+                       reg = <0x20>;
+                       interrupt-parent = <&gpa3>;
+                       interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+                       vcc-supply=<&ldo32_reg>;
+                       vdd-supply=<&ldo33_reg>;
+               };
+       };
index cbd75cf44739b19354decf0b0ebf3602cb2113c3..97acd6524ad7c37bc93cb3acc070fb171f76520c 100644 (file)
@@ -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
index d9f4cfcf34104dc1c579e14969c2249e81a66df7..7d9acff819a7899c0b8031554a073136cc8a1377 100644 (file)
@@ -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 (file)
index 0000000..916e2f3
--- /dev/null
@@ -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");