Input: mcs - Add MCS touchkey driver

This adds support for MELPAS MCS5000/MSC5080 touch key controllers.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

3 files changed, 252 insertions, 0 deletions

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index d8fa5d724c5..c7480934cee 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -297,6 +297,18 @@ config KEYBOARD_MAX7359
 	  To compile this driver as a module, choose M here: the
 	  module will be called max7359_keypad.
 
+config KEYBOARD_MCS
+	tristate "MELFAS MCS Touchkey"
+	depends on I2C
+	help
+	  Say Y here if you have the MELFAS MCS5000/5080 touchkey controller
+	  chip in your system.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mcs_touchkey.
+
 config KEYBOARD_IMX
 	tristate "IMX keypad support"
 	depends on ARCH_MXC
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 4596d0c6f92..0a16674ed3d 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_KEYBOARD_LOCOMO)		+= locomokbd.o
 obj-$(CONFIG_KEYBOARD_MAPLE)		+= maple_keyb.o
 obj-$(CONFIG_KEYBOARD_MATRIX)		+= matrix_keypad.o
 obj-$(CONFIG_KEYBOARD_MAX7359)		+= max7359_keypad.o
+obj-$(CONFIG_KEYBOARD_MCS)		+= mcs_touchkey.o
 obj-$(CONFIG_KEYBOARD_NEWTON)		+= newtonkbd.o
 obj-$(CONFIG_KEYBOARD_OMAP)		+= omap-keypad.o
 obj-$(CONFIG_KEYBOARD_OPENCORES)	+= opencores-kbd.o
diff --git a/drivers/input/keyboard/mcs_touchkey.c b/drivers/input/keyboard/mcs_touchkey.c
new file mode 100644
index 00000000000..63b849d7e90
--- /dev/null
+++ b/drivers/input/keyboard/mcs_touchkey.c
@@ -0,0 +1,239 @@
+/*
+ * mcs_touchkey.c - Touchkey driver for MELFAS MCS5000/5080 controller
+ *
+ * Copyright (C) 2010 Samsung Electronics Co.Ltd
+ * Author: HeungJun Kim <riverful.kim@samsung.com>
+ * Author: Joonyoung Shim <jy0922.shim@samsung.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/i2c/mcs.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+
+/* MCS5000 Touchkey */
+#define MCS5000_TOUCHKEY_STATUS		0x04
+#define MCS5000_TOUCHKEY_STATUS_PRESS	7
+#define MCS5000_TOUCHKEY_FW		0x0a
+#define MCS5000_TOUCHKEY_BASE_VAL	0x61
+
+/* MCS5080 Touchkey */
+#define MCS5080_TOUCHKEY_STATUS		0x00
+#define MCS5080_TOUCHKEY_STATUS_PRESS	3
+#define MCS5080_TOUCHKEY_FW		0x01
+#define MCS5080_TOUCHKEY_BASE_VAL	0x1
+
+enum mcs_touchkey_type {
+	MCS5000_TOUCHKEY,
+	MCS5080_TOUCHKEY,
+};
+
+struct mcs_touchkey_chip {
+	unsigned int status_reg;
+	unsigned int pressbit;
+	unsigned int press_invert;
+	unsigned int baseval;
+};
+
+struct mcs_touchkey_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+	struct mcs_touchkey_chip chip;
+	unsigned int key_code;
+	unsigned int key_val;
+	unsigned short keycodes[];
+};
+
+static irqreturn_t mcs_touchkey_interrupt(int irq, void *dev_id)
+{
+	struct mcs_touchkey_data *data = dev_id;
+	struct mcs_touchkey_chip *chip = &data->chip;
+	struct i2c_client *client = data->client;
+	struct input_dev *input = data->input_dev;
+	unsigned int key_val;
+	unsigned int pressed;
+	int val;
+
+	val = i2c_smbus_read_byte_data(client, chip->status_reg);
+	if (val < 0) {
+		dev_err(&client->dev, "i2c read error [%d]\n", val);
+		goto out;
+	}
+
+	pressed = (val & (1 << chip->pressbit)) >> chip->pressbit;
+	if (chip->press_invert)
+		pressed ^= chip->press_invert;
+
+	/* key_val is 0 when released, so we should use key_val of press. */
+	if (pressed) {
+		key_val = val & (0xff >> (8 - chip->pressbit));
+		if (!key_val)
+			goto out;
+		key_val -= chip->baseval;
+		data->key_code = data->keycodes[key_val];
+		data->key_val = key_val;
+	}
+
+	input_event(input, EV_MSC, MSC_SCAN, data->key_val);
+	input_report_key(input, data->key_code, pressed);
+	input_sync(input);
+
+	dev_dbg(&client->dev, "key %d %d %s\n", data->key_val, data->key_code,
+		pressed ? "pressed" : "released");
+
+ out:
+	return IRQ_HANDLED;
+}
+
+static int __devinit mcs_touchkey_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	const struct mcs_platform_data *pdata;
+	struct mcs_touchkey_data *data;
+	struct input_dev *input_dev;
+	unsigned int fw_reg;
+	int fw_ver;
+	int error;
+	int i;
+
+	pdata = client->dev.platform_data;
+	if (!pdata) {
+		dev_err(&client->dev, "no platform data defined\n");
+		return -EINVAL;
+	}
+
+	data = kzalloc(sizeof(struct mcs_touchkey_data) +
+			sizeof(data->keycodes[0]) * (pdata->key_maxval + 1),
+			GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!data || !input_dev) {
+		dev_err(&client->dev, "Failed to allocate memory\n");
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	data->client = client;
+	data->input_dev = input_dev;
+
+	if (id->driver_data == MCS5000_TOUCHKEY) {
+		data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
+		data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
+		data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
+		fw_reg = MCS5000_TOUCHKEY_FW;
+	} else {
+		data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
+		data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
+		data->chip.press_invert = 1;
+		data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
+		fw_reg = MCS5080_TOUCHKEY_FW;
+	}
+
+	fw_ver = i2c_smbus_read_byte_data(client, fw_reg);
+	if (fw_ver < 0) {
+		error = fw_ver;
+		dev_err(&client->dev, "i2c read error[%d]\n", error);
+		goto err_free_mem;
+	}
+	dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
+
+	input_dev->name = "MELPAS MCS Touchkey";
+	input_dev->id.bustype = BUS_I2C;
+	input_dev->dev.parent = &client->dev;
+	input_dev->evbit[0] = BIT_MASK(EV_KEY);
+	if (!pdata->no_autorepeat)
+		input_dev->evbit[0] |= BIT_MASK(EV_REP);
+	input_dev->keycode = data->keycodes;
+	input_dev->keycodesize = sizeof(data->keycodes[0]);
+	input_dev->keycodemax = pdata->key_maxval + 1;
+
+	for (i = 0; i < pdata->keymap_size; i++) {
+		unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
+		unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
+
+		data->keycodes[val] = code;
+		__set_bit(code, input_dev->keybit);
+	}
+
+	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+	input_set_drvdata(input_dev, data);
+
+	if (pdata->cfg_pin)
+		pdata->cfg_pin();
+
+	error = request_threaded_irq(client->irq, NULL, mcs_touchkey_interrupt,
+			IRQF_TRIGGER_FALLING, client->dev.driver->name, data);
+	if (error) {
+		dev_err(&client->dev, "Failed to register interrupt\n");
+		goto err_free_mem;
+	}
+
+	error = input_register_device(input_dev);
+	if (error)
+		goto err_free_irq;
+
+	i2c_set_clientdata(client, data);
+	return 0;
+
+err_free_irq:
+	free_irq(client->irq, data);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(data);
+	return error;
+}
+
+static int __devexit mcs_touchkey_remove(struct i2c_client *client)
+{
+	struct mcs_touchkey_data *data = i2c_get_clientdata(client);
+
+	free_irq(client->irq, data);
+	input_unregister_device(data->input_dev);
+	kfree(data);
+
+	return 0;
+}
+
+static const struct i2c_device_id mcs_touchkey_id[] = {
+	{ "mcs5000_touchkey", MCS5000_TOUCHKEY },
+	{ "mcs5080_touchkey", MCS5080_TOUCHKEY },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
+
+static struct i2c_driver mcs_touchkey_driver = {
+	.driver = {
+		.name	= "mcs_touchkey",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= mcs_touchkey_probe,
+	.remove		= __devexit_p(mcs_touchkey_remove),
+	.id_table	= mcs_touchkey_id,
+};
+
+static int __init mcs_touchkey_init(void)
+{
+	return i2c_add_driver(&mcs_touchkey_driver);
+}
+
+static void __exit mcs_touchkey_exit(void)
+{
+	i2c_del_driver(&mcs_touchkey_driver);
+}
+
+module_init(mcs_touchkey_init);
+module_exit(mcs_touchkey_exit);
+
+/* Module information */
+MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
+MODULE_AUTHOR("HeungJun Kim <riverful.kim@samsung.com>");
+MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
+MODULE_LICENSE("GPL");