input: mxt224: Atmel MaxTouch 224 driver

Adding driver to support the Atmel MaxTouch 224 multi-touch controller.

Change-Id: Ibf8de98c1f102e09f6204e7b57e49bcaf154f0af
Signed-off-by: Rom Lemarchand <rlemarchand@sta.samsung.com>

3 files changed, 661 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 4104103..69d8fd2 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -319,6 +319,18 @@ config TOUCHSCREEN_MK712
 	  To compile this driver as a module, choose M here: the
 	  module will be called mk712.
 
+config TOUCHSCREEN_MXT224
+	tristate "Atmel MaxTouch 224"
+	depends on I2C
+	help
+	  Say Y here to enable support for the Atmel MaxTouch 224 touch
+	  controller.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mxt224.
+
 config TOUCHSCREEN_HP600
 	tristate "HP Jornada 6xx touchscreen"
 	depends on SH_HP6XX && SH_ADC
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 0738f19..ae5aeaa 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_TOUCHSCREEN_MCS5000)	+= mcs5000_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MIGOR)		+= migor_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MTOUCH)	+= mtouch.o
 obj-$(CONFIG_TOUCHSCREEN_MK712)		+= mk712.o
+obj-$(CONFIG_TOUCHSCREEN_MXT224)	+= mxt224.o
 obj-$(CONFIG_TOUCHSCREEN_HP600)		+= hp680_ts_input.o
 obj-$(CONFIG_TOUCHSCREEN_HP7XX)		+= jornada720_ts.o
 obj-$(CONFIG_TOUCHSCREEN_HTCPEN)	+= htcpen.o
diff --git a/drivers/input/touchscreen/mxt224.c b/drivers/input/touchscreen/mxt224.c
new file mode 100644
index 0000000..07143b1
--- /dev/null
+++ b/drivers/input/touchscreen/mxt224.c
@@ -0,0 +1,648 @@
+/*
+ *  Copyright (C) 2010, Samsung Electronics Co. Ltd. All Rights Reserved.
+ *
+ *  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.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/earlysuspend.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/input/mxt224.h>
+#include <asm/unaligned.h>
+
+#define OBJECT_TABLE_START_ADDRESS	7
+#define OBJECT_TABLE_ELEMENT_SIZE	6
+
+#define CMD_RESET_OFFSET		0
+#define CMD_BACKUP_OFFSET		1
+
+#define DETECT_MSG_MASK			0x80
+#define PRESS_MSG_MASK			0x40
+#define RELEASE_MSG_MASK		0x20
+#define MOVE_MSG_MASK			0x10
+#define SUPPRESS_MSG_MASK		0x02
+
+#define ID_BLOCK_SIZE			7
+
+struct object_t {
+	u8 object_type;
+	u16 i2c_address;
+	u8 size;
+	u8 instances;
+	u8 num_report_ids;
+} __packed;
+
+struct finger_info {
+	s16 x;
+	s16 y;
+	s16 z;
+	u16 w;
+};
+
+struct mxt224_data {
+	struct i2c_client *client;
+	struct input_dev *input_dev;
+	struct early_suspend early_suspend;
+	u32 finger_mask;
+	int gpio_read_done;
+	struct object_t *objects;
+	u8 objects_len;
+	u8 tsp_version;
+	const u8 *power_cfg;
+	u8 finger_type;
+	u16 msg_proc;
+	u16 cmd_proc;
+	u16 msg_object_size;
+	u32 x_dropbits:2;
+	u32 y_dropbits:2;
+	void (*power_on)(void);
+	void (*power_off)(void);
+	int num_fingers;
+	struct finger_info fingers[];
+};
+
+static int read_mem(struct mxt224_data *data, u16 reg, u8 len, u8 *buf)
+{
+	int ret;
+	u16 le_reg = cpu_to_le16(reg);
+	struct i2c_msg msg[2] = {
+		{
+			.addr = data->client->addr,
+			.flags = 0,
+			.len = 2,
+			.buf = (u8 *)&le_reg,
+		},
+		{
+			.addr = data->client->addr,
+			.flags = I2C_M_RD,
+			.len = len,
+			.buf = buf,
+		},
+	};
+
+	ret = i2c_transfer(data->client->adapter, msg, 2);
+	if (ret < 0)
+		return ret;
+
+	return ret == 2 ? 0 : -EIO;
+}
+
+static int write_mem(struct mxt224_data *data, u16 reg, u8 len, const u8 *buf)
+{
+	int ret;
+	u8 tmp[len + 2];
+
+	put_unaligned_le16(cpu_to_le16(reg), tmp);
+	memcpy(tmp + 2, buf, len);
+
+	ret = i2c_master_send(data->client, tmp, sizeof(tmp));
+	if (ret < 0)
+		return ret;
+
+	return ret == sizeof(tmp) ? 0 : -EIO;
+}
+
+static int __devinit mxt224_reset(struct mxt224_data *data)
+{
+	u8 buf = 1u;
+	return write_mem(data, data->cmd_proc + CMD_RESET_OFFSET, 1, &buf);
+}
+
+static int __devinit mxt224_backup(struct mxt224_data *data)
+{
+	u8 buf = 0x55u;
+	return write_mem(data, data->cmd_proc + CMD_BACKUP_OFFSET, 1, &buf);
+}
+
+static int get_object_info(struct mxt224_data *data, u8 object_type, u16 *size,
+				u16 *address)
+{
+	int i;
+
+	for (i = 0; i < data->objects_len; i++) {
+		if (data->objects[i].object_type == object_type) {
+			*size = data->objects[i].size + 1;
+			*address = data->objects[i].i2c_address;
+			return 0;
+		}
+	}
+
+	return -ENODEV;
+}
+
+static int write_config(struct mxt224_data *data, u8 type, const u8 *cfg)
+{
+	int ret;
+	u16 address;
+	u16 size;
+
+	ret = get_object_info(data, type, &size, &address);
+
+	if (ret)
+		return ret;
+
+	return write_mem(data, address, size, cfg);
+}
+
+
+static u32 __devinit crc24(u32 crc, u8 byte1, u8 byte2)
+{
+	static const u32 crcpoly = 0x80001B;
+	u32 res;
+	u16 data_word;
+
+	data_word = (((u16)byte2) << 8) | byte1;
+	res = (crc << 1) ^ (u32)data_word;
+
+	if (res & 0x1000000)
+		res ^= crcpoly;
+
+	return res;
+}
+
+static int __devinit calculate_infoblock_crc(struct mxt224_data *data,
+							u32 *crc_pointer)
+{
+	u32 crc = 0;
+	u8 mem[7 + data->objects_len * 6];
+	int status;
+	int i;
+
+	status = read_mem(data, 0, sizeof(mem), mem);
+
+	if (status)
+		return status;
+
+	for (i = 0; i < sizeof(mem) - 1; i += 2)
+		crc = crc24(crc, mem[i], mem[i + 1]);
+
+	*crc_pointer = crc24(crc, mem[i], 0) & 0x00FFFFFF;
+
+	return 0;
+}
+
+static int __devinit mxt224_init_touch_driver(struct mxt224_data *data)
+{
+	struct object_t *object_table;
+	u32 read_crc = 0;
+	u32 calc_crc;
+	u16 crc_address;
+	u16 dummy;
+	int i;
+	u8 id[ID_BLOCK_SIZE];
+	int ret;
+	u8 type_count = 0;
+	u8 tmp;
+
+	ret = read_mem(data, 0, sizeof(id), id);
+	if (ret)
+		return ret;
+
+	dev_info(&data->client->dev, "family = %#02x, variant = %#02x, version "
+			"= %#02x, build = %d\n", id[0], id[1], id[2], id[3]);
+	dev_dbg(&data->client->dev, "matrix X size = %d\n", id[4]);
+	dev_dbg(&data->client->dev, "matrix Y size = %d\n", id[5]);
+
+	data->tsp_version = id[2];
+	data->objects_len = id[6];
+
+	object_table = kmalloc(data->objects_len * sizeof(*object_table),
+				GFP_KERNEL);
+	if (!object_table)
+		return -ENOMEM;
+
+	ret = read_mem(data, OBJECT_TABLE_START_ADDRESS,
+			data->objects_len * sizeof(*object_table),
+			(u8 *)object_table);
+	if (ret)
+		goto err;
+
+	for (i = 0; i < data->objects_len; i++) {
+		object_table[i].i2c_address =
+				le16_to_cpu(object_table[i].i2c_address);
+		tmp = 0;
+		if (object_table[i].num_report_ids) {
+			tmp = type_count + 1;
+			type_count += object_table[i].num_report_ids *
+						(object_table[i].instances + 1);
+		}
+		switch (object_table[i].object_type) {
+		case TOUCH_MULTITOUCHSCREEN_T9:
+			data->finger_type = tmp;
+			dev_dbg(&data->client->dev, "Finger type = %d\n",
+						data->finger_type);
+			break;
+		case GEN_MESSAGEPROCESSOR_T5:
+			data->msg_object_size = object_table[i].size + 1;
+			dev_dbg(&data->client->dev, "Message object size = "
+						"%d\n", data->msg_object_size);
+			break;
+		}
+	}
+
+	data->objects = object_table;
+
+	/* Verify CRC */
+	crc_address = OBJECT_TABLE_START_ADDRESS +
+			data->objects_len * OBJECT_TABLE_ELEMENT_SIZE;
+
+#ifdef __BIG_ENDIAN
+#error The following code will likely break on a big endian machine
+#endif
+	ret = read_mem(data, crc_address, 3, (u8 *)&read_crc);
+	if (ret)
+		goto err;
+
+	read_crc = le32_to_cpu(read_crc);
+
+	ret = calculate_infoblock_crc(data, &calc_crc);
+	if (ret)
+		goto err;
+
+	if (read_crc != calc_crc) {
+		dev_err(&data->client->dev, "CRC error\n");
+		ret = -EFAULT;
+		goto err;
+	}
+
+	ret = get_object_info(data, GEN_MESSAGEPROCESSOR_T5, &dummy,
+					&data->msg_proc);
+	if (ret)
+		goto err;
+
+	ret = get_object_info(data, GEN_COMMANDPROCESSOR_T6, &dummy,
+					&data->cmd_proc);
+	if (ret)
+		goto err;
+
+	return 0;
+
+err:
+	kfree(object_table);
+	return ret;
+}
+
+static void report_input_data(struct mxt224_data *data)
+{
+	int i;
+
+	for (i = 0; i < data->num_fingers; i++) {
+		if (data->fingers[i].z == -1)
+			continue;
+
+		input_report_abs(data->input_dev, ABS_MT_POSITION_X,
+					data->fingers[i].x);
+		input_report_abs(data->input_dev, ABS_MT_POSITION_Y,
+					data->fingers[i].y);
+		input_report_abs(data->input_dev, ABS_MT_TOUCH_MAJOR,
+					data->fingers[i].z);
+		input_report_abs(data->input_dev, ABS_MT_WIDTH_MAJOR,
+					data->fingers[i].w);
+		input_report_abs(data->input_dev, ABS_MT_TRACKING_ID, i);
+		input_mt_sync(data->input_dev);
+
+		if (data->fingers[i].z == 0)
+			data->fingers[i].z = -1;
+	}
+	data->finger_mask = 0;
+
+	input_sync(data->input_dev);
+}
+
+static irqreturn_t mxt224_irq_thread(int irq, void *ptr)
+{
+	struct mxt224_data *data = ptr;
+	int id;
+	u8 msg[data->msg_object_size];
+
+	do {
+		if (read_mem(data, data->msg_proc, sizeof(msg), msg))
+			return IRQ_HANDLED;
+
+		id = msg[0] - data->finger_type;
+
+		/* If not a touch event, then keep going */
+		if (id < 0 || id >= data->num_fingers)
+			continue;
+
+		if (data->finger_mask & (1U << id))
+			report_input_data(data);
+
+		if (msg[1] & RELEASE_MSG_MASK) {
+			data->fingers[id].z = 0;
+			data->fingers[id].w = msg[5];
+			data->finger_mask |= 1U << id;
+		} else if ((msg[1] & DETECT_MSG_MASK) && (msg[1] &
+				(PRESS_MSG_MASK | MOVE_MSG_MASK))) {
+			data->fingers[id].z = msg[6];
+			data->fingers[id].w = msg[5];
+			data->fingers[id].x = ((msg[2] << 4) | (msg[4] >> 4)) >>
+							data->x_dropbits;
+			data->fingers[id].y = ((msg[3] << 4) |
+					(msg[4] & 0xF)) >> data->y_dropbits;
+			data->finger_mask |= 1U << id;
+		} else if ((msg[1] & SUPPRESS_MSG_MASK) &&
+			   (data->fingers[id].z != -1)) {
+			data->fingers[id].z = 0;
+			data->fingers[id].w = msg[5];
+			data->finger_mask |= 1U << id;
+		} else {
+			dev_dbg(&data->client->dev, "Unknown state %#02x %#02x"
+						"\n", msg[0], msg[1]);
+			continue;
+		}
+	} while (!gpio_get_value(data->gpio_read_done));
+
+	if (data->finger_mask)
+		report_input_data(data);
+
+	return IRQ_HANDLED;
+}
+
+static int mxt224_internal_suspend(struct mxt224_data *data)
+{
+	static const u8 sleep_power_cfg[3];
+	int ret;
+	int i;
+
+	ret = write_config(data, GEN_POWERCONFIG_T7, sleep_power_cfg);
+	if (ret)
+		return ret;
+
+
+	for (i = 0; i < data->num_fingers; i++) {
+		if (data->fingers[i].z == -1)
+			continue;
+		data->fingers[i].z = 0;
+	}
+	report_input_data(data);
+
+	data->power_off();
+
+	return 0;
+}
+
+static int mxt224_internal_resume(struct mxt224_data *data)
+{
+	int ret;
+	int i;
+
+	data->power_on();
+
+	i = 0;
+	do {
+		ret = write_config(data, GEN_POWERCONFIG_T7, data->power_cfg);
+		msleep(20);
+		i++;
+	} while (ret && i < 10);
+
+	return ret;
+}
+
+#ifdef CONFIG_HAS_EARLYSUSPEND
+#define mxt224_suspend	NULL
+#define mxt224_resume	NULL
+
+static void mxt224_early_suspend(struct early_suspend *h)
+{
+	struct mxt224_data *data = container_of(h, struct mxt224_data,
+								early_suspend);
+	disable_irq(data->client->irq);
+	mxt224_internal_suspend(data);
+}
+
+static void mxt224_late_resume(struct early_suspend *h)
+{
+	struct mxt224_data *data = container_of(h, struct mxt224_data,
+								early_suspend);
+	mxt224_internal_resume(data);
+	enable_irq(data->client->irq);
+}
+#else
+static int mxt224_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mxt224_data *data = i2c_get_clientdata(client);
+
+	return mxt224_internal_suspend(data);
+}
+
+static int mxt224_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct mxt224_data *data = i2c_get_clientdata(client);
+
+	return mxt224_internal_resume(data);
+}
+#endif
+
+static int __devinit mxt224_probe(struct i2c_client *client,
+					const struct i2c_device_id *id)
+{
+	struct mxt224_platform_data *pdata = client->dev.platform_data;
+	struct mxt224_data *data;
+	struct input_dev *input_dev;
+	int ret;
+	int i;
+
+	if (!pdata) {
+		dev_err(&client->dev, "missing platform data\n");
+		return -ENODEV;
+	}
+
+	if (pdata->max_finger_touches <= 0)
+		return -EINVAL;
+
+	data = kzalloc(sizeof(*data) + pdata->max_finger_touches *
+					sizeof(*data->fingers), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->num_fingers = pdata->max_finger_touches;
+	data->power_on = pdata->power_on;
+	data->power_off = pdata->power_off;
+
+	data->client = client;
+	i2c_set_clientdata(client, data);
+
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		ret = -ENOMEM;
+		dev_err(&client->dev, "input device allocation failed\n");
+		goto err_alloc_dev;
+	}
+	data->input_dev = input_dev;
+	input_set_drvdata(input_dev, data);
+	input_dev->name = "mxt224_ts_input";
+
+	set_bit(EV_ABS, input_dev->evbit);
+
+	input_set_abs_params(input_dev, ABS_MT_POSITION_X, pdata->min_x,
+			pdata->max_x, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_Y, pdata->min_y,
+			pdata->max_y, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, pdata->min_z,
+			pdata->max_z, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_WIDTH_MAJOR, pdata->min_w,
+			pdata->max_w, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_TRACKING_ID, 0,
+			data->num_fingers - 1, 0, 0);
+
+	ret = input_register_device(input_dev);
+	if (ret) {
+		input_free_device(input_dev);
+		goto err_reg_dev;
+	}
+
+	data->gpio_read_done = pdata->gpio_read_done;
+	ret = gpio_request(data->gpio_read_done, "touch read done");
+	if (ret)
+		goto err_gpio_req;
+
+	data->power_on();
+
+	ret = mxt224_init_touch_driver(data);
+	if (ret) {
+		dev_err(&client->dev, "chip initialization failed\n");
+		goto err_init_drv;
+	}
+
+	for (i = 0; pdata->config[i][0] != RESERVED_T255; i++) {
+		ret = write_config(data, pdata->config[i][0],
+							pdata->config[i] + 1);
+		if (ret)
+			goto err_config;
+
+		if (pdata->config[i][0] == GEN_POWERCONFIG_T7)
+			data->power_cfg = pdata->config[i] + 1;
+
+		if (pdata->config[i][0] == TOUCH_MULTITOUCHSCREEN_T9) {
+			/* Are x and y inverted? */
+			if (pdata->config[i][10] & 0x1) {
+				data->x_dropbits =
+					(!(pdata->config[i][22] & 0xC)) << 1;
+				data->y_dropbits =
+					(!(pdata->config[i][20] & 0xC)) << 1;
+			} else {
+				data->x_dropbits =
+					(!(pdata->config[i][20] & 0xC)) << 1;
+				data->y_dropbits =
+					(!(pdata->config[i][22] & 0xC)) << 1;
+			}
+		}
+	}
+
+	ret = mxt224_backup(data);
+	if (ret)
+		goto err_backup;
+
+	/* reset the touch IC. */
+	ret = mxt224_reset(data);
+	if (ret)
+		goto err_reset;
+
+	msleep(60);
+
+	for (i = 0; i < data->num_fingers; i++)
+		data->fingers[i].z = -1;
+
+	ret = request_threaded_irq(client->irq, NULL, mxt224_irq_thread,
+		IRQF_TRIGGER_LOW | IRQF_ONESHOT, "mxt224_ts", data);
+	if (ret < 0)
+		goto err_irq;
+
+#ifdef CONFIG_HAS_EARLYSUSPEND
+	data->early_suspend.level = EARLY_SUSPEND_LEVEL_BLANK_SCREEN + 1;
+	data->early_suspend.suspend = mxt224_early_suspend;
+	data->early_suspend.resume = mxt224_late_resume;
+	register_early_suspend(&data->early_suspend);
+#endif
+
+	return 0;
+
+err_irq:
+err_reset:
+err_backup:
+err_config:
+	kfree(data->objects);
+err_init_drv:
+	gpio_free(data->gpio_read_done);
+err_gpio_req:
+	data->power_off();
+	input_unregister_device(input_dev);
+err_reg_dev:
+err_alloc_dev:
+	kfree(data);
+	return ret;
+}
+
+static int __devexit mxt224_remove(struct i2c_client *client)
+{
+	struct mxt224_data *data = i2c_get_clientdata(client);
+
+#ifdef CONFIG_HAS_EARLYSUSPEND
+	unregister_early_suspend(&data->early_suspend);
+#endif
+	free_irq(client->irq, data);
+	kfree(data->objects);
+	gpio_free(data->gpio_read_done);
+	data->power_off();
+	input_unregister_device(data->input_dev);
+	kfree(data);
+
+	return 0;
+}
+
+static struct i2c_device_id mxt224_idtable[] = {
+	{MXT224_DEV_NAME, 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(i2c, mxt224_idtable);
+
+static const struct dev_pm_ops mxt224_pm_ops = {
+	.suspend = mxt224_suspend,
+	.resume = mxt224_resume,
+};
+
+static struct i2c_driver mxt224_i2c_driver = {
+	.id_table = mxt224_idtable,
+	.probe = mxt224_probe,
+	.remove = __devexit_p(mxt224_remove),
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= MXT224_DEV_NAME,
+		.pm	= &mxt224_pm_ops,
+	},
+};
+
+static int __init mxt224_init(void)
+{
+	return i2c_add_driver(&mxt224_i2c_driver);
+}
+
+static void __exit mxt224_exit(void)
+{
+	i2c_del_driver(&mxt224_i2c_driver);
+}
+module_init(mxt224_init);
+module_exit(mxt224_exit);
+
+MODULE_DESCRIPTION("Atmel MaXTouch 224 driver");
+MODULE_AUTHOR("Rom Lemarchand <rlemarchand@sta.samsung.com>");
+MODULE_LICENSE("GPL");