Input: add MELFAS mms114 touchscreen driver

This is a initial driver for new touchscreen chip mms114 of MELFAS.
It uses I2C interface and supports 10 multi touch.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/touchscreen/mms114.c b/drivers/input/touchscreen/mms114.c
new file mode 100644
index 0000000..49c44bb
--- /dev/null
+++ b/drivers/input/touchscreen/mms114.c
@@ -0,0 +1,544 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics Co.Ltd
+ * 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 version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/i2c/mms114.h>
+#include <linux/input/mt.h>
+#include <linux/interrupt.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+/* Write only registers */
+#define MMS114_MODE_CONTROL		0x01
+#define MMS114_OPERATION_MODE_MASK	0xE
+#define MMS114_ACTIVE			(1 << 1)
+
+#define MMS114_XY_RESOLUTION_H		0x02
+#define MMS114_X_RESOLUTION		0x03
+#define MMS114_Y_RESOLUTION		0x04
+#define MMS114_CONTACT_THRESHOLD	0x05
+#define MMS114_MOVING_THRESHOLD		0x06
+
+/* Read only registers */
+#define MMS114_PACKET_SIZE		0x0F
+#define MMS114_INFOMATION		0x10
+#define MMS114_TSP_REV			0xF0
+
+/* Minimum delay time is 50us between stop and start signal of i2c */
+#define MMS114_I2C_DELAY		50
+
+/* 200ms needs after power on */
+#define MMS114_POWERON_DELAY		200
+
+/* Touchscreen absolute values */
+#define MMS114_MAX_AREA			0xff
+
+#define MMS114_MAX_TOUCH		10
+#define MMS114_PACKET_NUM		8
+
+/* Touch type */
+#define MMS114_TYPE_NONE		0
+#define MMS114_TYPE_TOUCHSCREEN		1
+#define MMS114_TYPE_TOUCHKEY		2
+
+struct mms114_data {
+	struct i2c_client	*client;
+	struct input_dev	*input_dev;
+	struct regulator	*core_reg;
+	struct regulator	*io_reg;
+	const struct mms114_platform_data	*pdata;
+
+	/* Use cache data for mode control register(write only) */
+	u8			cache_mode_control;
+};
+
+struct mms114_touch {
+	u8 id:4, reserved_bit4:1, type:2, pressed:1;
+	u8 x_hi:4, y_hi:4;
+	u8 x_lo;
+	u8 y_lo;
+	u8 width;
+	u8 strength;
+	u8 reserved[2];
+} __packed;
+
+static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
+			     unsigned int len, u8 *val)
+{
+	struct i2c_client *client = data->client;
+	struct i2c_msg xfer[2];
+	u8 buf = reg & 0xff;
+	int error;
+
+	if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
+		BUG();
+
+	/* Write register: use repeated start */
+	xfer[0].addr = client->addr;
+	xfer[0].flags = I2C_M_TEN | I2C_M_NOSTART;
+	xfer[0].len = 1;
+	xfer[0].buf = &buf;
+
+	/* Read data */
+	xfer[1].addr = client->addr;
+	xfer[1].flags = I2C_M_RD;
+	xfer[1].len = len;
+	xfer[1].buf = val;
+
+	error = i2c_transfer(client->adapter, xfer, 2);
+	if (error != 2) {
+		dev_err(&client->dev,
+			"%s: i2c transfer failed (%d)\n", __func__, error);
+		return error < 0 ? error : -EIO;
+	}
+	udelay(MMS114_I2C_DELAY);
+
+	return 0;
+}
+
+static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
+{
+	u8 val;
+	int error;
+
+	if (reg == MMS114_MODE_CONTROL)
+		return data->cache_mode_control;
+
+	error = __mms114_read_reg(data, reg, 1, &val);
+	return error < 0 ? error : val;
+}
+
+static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
+			    unsigned int val)
+{
+	struct i2c_client *client = data->client;
+	u8 buf[2];
+	int error;
+
+	buf[0] = reg & 0xff;
+	buf[1] = val & 0xff;
+
+	error = i2c_master_send(client, buf, 2);
+	if (error != 2) {
+		dev_err(&client->dev,
+			"%s: i2c send failed (%d)\n", __func__, error);
+		return error < 0 ? error : -EIO;
+	}
+	udelay(MMS114_I2C_DELAY);
+
+	if (reg == MMS114_MODE_CONTROL)
+		data->cache_mode_control = val;
+
+	return 0;
+}
+
+static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
+{
+	const struct mms114_platform_data *pdata = data->pdata;
+	struct i2c_client *client = data->client;
+	struct input_dev *input_dev = data->input_dev;
+	unsigned int id;
+	unsigned int x;
+	unsigned int y;
+
+	if (touch->id > MMS114_MAX_TOUCH) {
+		dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
+		return;
+	}
+
+	if (touch->type != MMS114_TYPE_TOUCHSCREEN) {
+		dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type);
+		return;
+	}
+
+	id = touch->id - 1;
+	x = touch->x_lo | touch->x_hi << 8;
+	y = touch->y_lo | touch->y_hi << 8;
+	if (x > pdata->x_size || y > pdata->y_size) {
+		dev_dbg(&client->dev,
+			"Wrong touch coordinates (%d, %d)\n", x, y);
+		return;
+	}
+
+	if (pdata->x_invert)
+		x = pdata->x_size - x;
+	if (pdata->y_invert)
+		y = pdata->y_size - y;
+
+	dev_dbg(&client->dev,
+		"id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
+		id, touch->type, touch->pressed,
+		x, y, touch->width, touch->strength);
+
+	input_mt_slot(input_dev, id);
+	input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
+
+	if (touch->pressed) {
+		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
+		input_report_abs(input_dev, ABS_MT_POSITION_X, x);
+		input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
+		input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
+	}
+}
+
+static irqreturn_t mms114_interrupt(int irq, void *dev_id)
+{
+	struct mms114_data *data = dev_id;
+	struct input_dev *input_dev = data->input_dev;
+	struct mms114_touch touch[MMS114_MAX_TOUCH];
+	int packet_size;
+	int touch_size;
+	int index;
+	int error;
+
+	mutex_lock(&input_dev->mutex);
+	if (!input_dev->users) {
+		mutex_unlock(&input_dev->mutex);
+		goto out;
+	}
+	mutex_unlock(&input_dev->mutex);
+
+	packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
+	if (packet_size <= 0)
+		goto out;
+
+	touch_size = packet_size / MMS114_PACKET_NUM;
+
+	error = __mms114_read_reg(data, MMS114_INFOMATION, packet_size,
+			(u8 *)touch);
+	if (error < 0)
+		goto out;
+
+	for (index = 0; index < touch_size; index++)
+		mms114_process_mt(data, touch + index);
+
+	input_mt_report_pointer_emulation(data->input_dev, true);
+	input_sync(data->input_dev);
+
+out:
+	return IRQ_HANDLED;
+}
+
+static int mms114_set_active(struct mms114_data *data, bool active)
+{
+	int val;
+
+	val = mms114_read_reg(data, MMS114_MODE_CONTROL);
+	if (val < 0)
+		return val;
+
+	val &= ~MMS114_OPERATION_MODE_MASK;
+
+	/* If active is false, sleep mode */
+	if (active)
+		val |= MMS114_ACTIVE;
+
+	return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
+}
+
+static int mms114_get_version(struct mms114_data *data)
+{
+	struct device *dev = &data->client->dev;
+	u8 buf[6];
+	int error;
+
+	error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
+	if (error < 0)
+		return error;
+
+	dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
+		 buf[0], buf[1], buf[3]);
+
+	return 0;
+}
+
+static int mms114_setup_regs(struct mms114_data *data)
+{
+	const struct mms114_platform_data *pdata = data->pdata;
+	int val;
+	int error;
+
+	error = mms114_get_version(data);
+	if (error < 0)
+		return error;
+
+	error = mms114_set_active(data, true);
+	if (error < 0)
+		return error;
+
+	val = (pdata->x_size >> 8) & 0xf;
+	val |= ((pdata->y_size >> 8) & 0xf) << 4;
+	error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
+	if (error < 0)
+		return error;
+
+	val = pdata->x_size & 0xff;
+	error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
+	if (error < 0)
+		return error;
+
+	val = pdata->y_size & 0xff;
+	error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
+	if (error < 0)
+		return error;
+
+	if (pdata->contact_threshold) {
+		error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
+				pdata->contact_threshold);
+		if (error < 0)
+			return error;
+	}
+
+	if (pdata->moving_threshold) {
+		error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
+				pdata->moving_threshold);
+		if (error < 0)
+			return error;
+	}
+
+	return 0;
+}
+
+static int mms114_start(struct mms114_data *data)
+{
+	struct i2c_client *client = data->client;
+	int error;
+
+	if (data->core_reg)
+		regulator_enable(data->core_reg);
+	if (data->io_reg)
+		regulator_enable(data->io_reg);
+	mdelay(MMS114_POWERON_DELAY);
+
+	error = mms114_setup_regs(data);
+	if (error < 0)
+		return error;
+
+	if (data->pdata->cfg_pin)
+		data->pdata->cfg_pin(true);
+
+	enable_irq(client->irq);
+
+	return 0;
+}
+
+static void mms114_stop(struct mms114_data *data)
+{
+	struct i2c_client *client = data->client;
+
+	disable_irq(client->irq);
+
+	if (data->pdata->cfg_pin)
+		data->pdata->cfg_pin(false);
+
+	if (data->io_reg)
+		regulator_disable(data->io_reg);
+	if (data->core_reg)
+		regulator_disable(data->core_reg);
+}
+
+static int mms114_input_open(struct input_dev *dev)
+{
+	struct mms114_data *data = input_get_drvdata(dev);
+
+	return mms114_start(data);
+}
+
+static void mms114_input_close(struct input_dev *dev)
+{
+	struct mms114_data *data = input_get_drvdata(dev);
+
+	mms114_stop(data);
+}
+
+static int __devinit mms114_probe(struct i2c_client *client,
+				  const struct i2c_device_id *id)
+{
+	struct mms114_data *data;
+	struct input_dev *input_dev;
+	int error;
+
+	if (!client->dev.platform_data) {
+		dev_err(&client->dev, "Need platform data\n");
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(client->adapter,
+				I2C_FUNC_PROTOCOL_MANGLING)) {
+		dev_err(&client->dev,
+			"Need i2c bus that supports protocol mangling\n");
+		return -ENODEV;
+	}
+
+	data = kzalloc(sizeof(struct mms114_data), 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;
+	data->pdata = client->dev.platform_data;
+
+	input_dev->name = "MELPAS MMS114 Touchscreen";
+	input_dev->id.bustype = BUS_I2C;
+	input_dev->dev.parent = &client->dev;
+	input_dev->open = mms114_input_open;
+	input_dev->close = mms114_input_close;
+
+	__set_bit(EV_ABS, input_dev->evbit);
+	__set_bit(EV_KEY, input_dev->evbit);
+	__set_bit(BTN_TOUCH, input_dev->keybit);
+	input_set_abs_params(input_dev, ABS_X, 0, data->pdata->x_size, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, 0, data->pdata->y_size, 0, 0);
+
+	/* For multi touch */
+	input_mt_init_slots(input_dev, MMS114_MAX_TOUCH);
+	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
+			     0, MMS114_MAX_AREA, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
+			     0, data->pdata->x_size, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
+			     0, data->pdata->y_size, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
+
+	input_set_drvdata(input_dev, data);
+	i2c_set_clientdata(client, data);
+
+	data->core_reg = regulator_get(&client->dev, "avdd");
+	if (IS_ERR(data->core_reg)) {
+		error = PTR_ERR(data->core_reg);
+		dev_err(&client->dev,
+			"Unable to get the Core regulator (%d)\n", error);
+		goto err_free_mem;
+	}
+
+	data->io_reg = regulator_get(&client->dev, "vdd");
+	if (IS_ERR(data->io_reg)) {
+		error = PTR_ERR(data->io_reg);
+		dev_err(&client->dev,
+			"Unable to get the IO regulator (%d)\n", error);
+		goto err_core_reg;
+	}
+
+	error = request_threaded_irq(client->irq, NULL, mms114_interrupt,
+			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "mms114", data);
+	if (error) {
+		dev_err(&client->dev, "Failed to register interrupt\n");
+		goto err_io_reg;
+	}
+	disable_irq(client->irq);
+
+	error = input_register_device(data->input_dev);
+	if (error)
+		goto err_free_irq;
+
+	return 0;
+
+err_free_irq:
+	free_irq(client->irq, data);
+err_io_reg:
+	regulator_put(data->io_reg);
+err_core_reg:
+	regulator_put(data->core_reg);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(data);
+	return error;
+}
+
+static int __devexit mms114_remove(struct i2c_client *client)
+{
+	struct mms114_data *data = i2c_get_clientdata(client);
+
+	free_irq(client->irq, data);
+	regulator_put(data->io_reg);
+	regulator_put(data->core_reg);
+	input_unregister_device(data->input_dev);
+	kfree(data);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mms114_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mms114_data *data = i2c_get_clientdata(client);
+	struct input_dev *input_dev = data->input_dev;
+	int id;
+
+	/* Release all touch */
+	for (id = 0; id < MMS114_MAX_TOUCH; id++) {
+		input_mt_slot(input_dev, id);
+		input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false);
+	}
+
+	input_mt_report_pointer_emulation(input_dev, true);
+	input_sync(input_dev);
+
+	mutex_lock(&input_dev->mutex);
+	if (input_dev->users)
+		mms114_stop(data);
+	mutex_unlock(&input_dev->mutex);
+
+	return 0;
+}
+
+static int mms114_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mms114_data *data = i2c_get_clientdata(client);
+	struct input_dev *input_dev = data->input_dev;
+	int error;
+
+	mutex_lock(&input_dev->mutex);
+	if (input_dev->users) {
+		error = mms114_start(data);
+		if (error < 0) {
+			mutex_unlock(&input_dev->mutex);
+			return error;
+		}
+	}
+	mutex_unlock(&input_dev->mutex);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
+
+static const struct i2c_device_id mms114_id[] = {
+	{ "mms114", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mms114_id);
+
+static struct i2c_driver mms114_driver = {
+	.driver = {
+		.name	= "mms114",
+		.owner	= THIS_MODULE,
+		.pm	= &mms114_pm_ops,
+	},
+	.probe		= mms114_probe,
+	.remove		= __devexit_p(mms114_remove),
+	.id_table	= mms114_id,
+};
+
+module_i2c_driver(mms114_driver);
+
+/* Module information */
+MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
+MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
+MODULE_LICENSE("GPL");