[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / input / keyboard / mpr121_touchkey.c

/*
 * Touchkey driver for Freescale MPR121 Controllor
 *
 * Copyright (C) 2011 Freescale Semiconductor, Inc.
 * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
 *
 * Based on mcs_touchkey.c
 *
 * 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/input.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/i2c/mpr121_touchkey.h>

/* Register definitions */
#define ELE_TOUCH_STATUS_0_ADDR	0x0
#define ELE_TOUCH_STATUS_1_ADDR	0X1
#define MHD_RISING_ADDR		0x2b
#define NHD_RISING_ADDR		0x2c
#define NCL_RISING_ADDR		0x2d
#define FDL_RISING_ADDR		0x2e
#define MHD_FALLING_ADDR	0x2f
#define NHD_FALLING_ADDR	0x30
#define NCL_FALLING_ADDR	0x31
#define FDL_FALLING_ADDR	0x32
#define ELE0_TOUCH_THRESHOLD_ADDR	0x41
#define ELE0_RELEASE_THRESHOLD_ADDR	0x42
#define AFE_CONF_ADDR			0x5c
#define FILTER_CONF_ADDR		0x5d

/*
 * ELECTRODE_CONF_ADDR: This register configures the number of
 * enabled capacitance sensing inputs and its run/suspend mode.
 */
#define ELECTRODE_CONF_ADDR		0x5e
#define ELECTRODE_CONF_QUICK_CHARGE	0x80
#define AUTO_CONFIG_CTRL_ADDR		0x7b
#define AUTO_CONFIG_USL_ADDR		0x7d
#define AUTO_CONFIG_LSL_ADDR		0x7e
#define AUTO_CONFIG_TL_ADDR		0x7f

/* Threshold of touch/release trigger */
#define TOUCH_THRESHOLD			0x08
#define RELEASE_THRESHOLD		0x05
/* Masks for touch and release triggers */
#define TOUCH_STATUS_MASK		0xfff
/* MPR121 has 12 keys */
#define MPR121_MAX_KEY_COUNT		12

struct mpr121_touchkey {
	struct i2c_client	*client;
	struct input_dev	*input_dev;
	unsigned int		key_val;
	unsigned int		statusbits;
	unsigned int		keycount;
	u16			keycodes[MPR121_MAX_KEY_COUNT];
};

struct mpr121_init_register {
	int addr;
	u8 val;
};

static const struct mpr121_init_register init_reg_table[] = {
	{ MHD_RISING_ADDR,	0x1 },
	{ NHD_RISING_ADDR,	0x1 },
	{ MHD_FALLING_ADDR,	0x1 },
	{ NHD_FALLING_ADDR,	0x1 },
	{ NCL_FALLING_ADDR,	0xff },
	{ FDL_FALLING_ADDR,	0x02 },
	{ FILTER_CONF_ADDR,	0x04 },
	{ AFE_CONF_ADDR,	0x0b },
	{ AUTO_CONFIG_CTRL_ADDR, 0x0b },
};

static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
{
	struct mpr121_touchkey *mpr121 = dev_id;
	struct i2c_client *client = mpr121->client;
	struct input_dev *input = mpr121->input_dev;
	unsigned long bit_changed;
	unsigned int key_num;
	int reg;

	reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
	if (reg < 0) {
		dev_err(&client->dev, "i2c read error [%d]\n", reg);
		goto out;
	}

	reg <<= 8;
	reg |= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
	if (reg < 0) {
		dev_err(&client->dev, "i2c read error [%d]\n", reg);
		goto out;
	}

	reg &= TOUCH_STATUS_MASK;
	/* use old press bit to figure out which bit changed */
	bit_changed = reg ^ mpr121->statusbits;
	mpr121->statusbits = reg;
	for_each_set_bit(key_num, &bit_changed, mpr121->keycount) {
		unsigned int key_val, pressed;

		pressed = reg & BIT(key_num);
		key_val = mpr121->keycodes[key_num];

		input_event(input, EV_MSC, MSC_SCAN, key_num);
		input_report_key(input, key_val, pressed);

		dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
			pressed ? "pressed" : "released");

	}
	input_sync(input);

out:
	return IRQ_HANDLED;
}

static int mpr121_phys_init(const struct mpr121_platform_data *pdata,
				      struct mpr121_touchkey *mpr121,
				      struct i2c_client *client)
{
	const struct mpr121_init_register *reg;
	unsigned char usl, lsl, tl, eleconf;
	int i, t, vdd, ret;

	/* Set up touch/release threshold for ele0-ele11 */
	for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
		t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
		ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
		if (ret < 0)
			goto err_i2c_write;
		ret = i2c_smbus_write_byte_data(client, t + 1,
						RELEASE_THRESHOLD);
		if (ret < 0)
			goto err_i2c_write;
	}

	/* Set up init register */
	for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
		reg = &init_reg_table[i];
		ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
		if (ret < 0)
			goto err_i2c_write;
	}


	/*
	 * Capacitance on sensing input varies and needs to be compensated.
	 * The internal MPR121-auto-configuration can do this if it's
	 * registers are set properly (based on pdata->vdd_uv).
	 */
	vdd = pdata->vdd_uv / 1000;
	usl = ((vdd - 700) * 256) / vdd;
	lsl = (usl * 65) / 100;
	tl = (usl * 90) / 100;
	ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
	ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
	ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);

	/*
	 * Quick charge bit will let the capacitive charge to ready
	 * state quickly, or the buttons may not function after system
	 * boot.
	 */
	eleconf = mpr121->keycount | ELECTRODE_CONF_QUICK_CHARGE;
	ret |= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
					 eleconf);
	if (ret != 0)
		goto err_i2c_write;

	dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);

	return 0;

err_i2c_write:
	dev_err(&client->dev, "i2c write error: %d\n", ret);
	return ret;
}

static int mpr_touchkey_probe(struct i2c_client *client,
			      const struct i2c_device_id *id)
{
	const struct mpr121_platform_data *pdata = client->dev.platform_data;
	struct mpr121_touchkey *mpr121;
	struct input_dev *input_dev;
	int error;
	int i;

	if (!pdata) {
		dev_err(&client->dev, "no platform data defined\n");
		return -EINVAL;
	}

	if (!pdata->keymap || !pdata->keymap_size) {
		dev_err(&client->dev, "missing keymap data\n");
		return -EINVAL;
	}

	if (pdata->keymap_size > MPR121_MAX_KEY_COUNT) {
		dev_err(&client->dev, "too many keys defined\n");
		return -EINVAL;
	}

	if (!client->irq) {
		dev_err(&client->dev, "irq number should not be zero\n");
		return -EINVAL;
	}

	mpr121 = kzalloc(sizeof(struct mpr121_touchkey), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!mpr121 || !input_dev) {
		dev_err(&client->dev, "Failed to allocate memory\n");
		error = -ENOMEM;
		goto err_free_mem;
	}

	mpr121->client = client;
	mpr121->input_dev = input_dev;
	mpr121->keycount = pdata->keymap_size;

	input_dev->name = "Freescale MPR121 Touchkey";
	input_dev->id.bustype = BUS_I2C;
	input_dev->dev.parent = &client->dev;
	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
	input_set_capability(input_dev, EV_MSC, MSC_SCAN);

	input_dev->keycode = mpr121->keycodes;
	input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
	input_dev->keycodemax = mpr121->keycount;

	for (i = 0; i < pdata->keymap_size; i++) {
		input_set_capability(input_dev, EV_KEY, pdata->keymap[i]);
		mpr121->keycodes[i] = pdata->keymap[i];
	}

	error = mpr121_phys_init(pdata, mpr121, client);
	if (error) {
		dev_err(&client->dev, "Failed to init register\n");
		goto err_free_mem;
	}

	error = request_threaded_irq(client->irq, NULL,
				     mpr_touchkey_interrupt,
				     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
				     client->dev.driver->name, mpr121);
	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, mpr121);
	device_init_wakeup(&client->dev, pdata->wakeup);

	return 0;

err_free_irq:
	free_irq(client->irq, mpr121);
err_free_mem:
	input_free_device(input_dev);
	kfree(mpr121);
	return error;
}

static int mpr_touchkey_remove(struct i2c_client *client)
{
	struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);

	free_irq(client->irq, mpr121);
	input_unregister_device(mpr121->input_dev);
	kfree(mpr121);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int mpr_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);

	if (device_may_wakeup(&client->dev))
		enable_irq_wake(client->irq);

	i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);

	return 0;
}

static int mpr_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);

	if (device_may_wakeup(&client->dev))
		disable_irq_wake(client->irq);

	i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
				  mpr121->keycount);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);

static const struct i2c_device_id mpr121_id[] = {
	{ "mpr121_touchkey", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mpr121_id);

static struct i2c_driver mpr_touchkey_driver = {
	.driver = {
		.name	= "mpr121",
		.owner	= THIS_MODULE,
		.pm	= &mpr121_touchkey_pm_ops,
	},
	.id_table	= mpr121_id,
	.probe		= mpr_touchkey_probe,
	.remove		= mpr_touchkey_remove,
};

module_i2c_driver(mpr_touchkey_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");
Commit	Line	Data
36682b81 ZJ	1	/*
	2	* Touchkey driver for Freescale MPR121 Controllor
	3	*
	4	* Copyright (C) 2011 Freescale Semiconductor, Inc.
	5	* Author: Zhang Jiejing <jiejing.zhang@freescale.com>
	6	*
	7	* Based on mcs_touchkey.c
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/init.h>
	17	#include <linux/input.h>
	18	#include <linux/i2c.h>
	19	#include <linux/slab.h>
	20	#include <linux/delay.h>
	21	#include <linux/bitops.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/i2c/mpr121_touchkey.h>
	24
	25	/* Register definitions */
	26	#define ELE_TOUCH_STATUS_0_ADDR 0x0
	27	#define ELE_TOUCH_STATUS_1_ADDR 0X1
	28	#define MHD_RISING_ADDR 0x2b
	29	#define NHD_RISING_ADDR 0x2c
	30	#define NCL_RISING_ADDR 0x2d
	31	#define FDL_RISING_ADDR 0x2e
	32	#define MHD_FALLING_ADDR 0x2f
	33	#define NHD_FALLING_ADDR 0x30
	34	#define NCL_FALLING_ADDR 0x31
	35	#define FDL_FALLING_ADDR 0x32
	36	#define ELE0_TOUCH_THRESHOLD_ADDR 0x41
	37	#define ELE0_RELEASE_THRESHOLD_ADDR 0x42
	38	#define AFE_CONF_ADDR 0x5c
	39	#define FILTER_CONF_ADDR 0x5d
	40
	41	/*
	42	* ELECTRODE_CONF_ADDR: This register configures the number of
	43	* enabled capacitance sensing inputs and its run/suspend mode.
	44	*/
	45	#define ELECTRODE_CONF_ADDR 0x5e
c7b4a5d5	46	#define ELECTRODE_CONF_QUICK_CHARGE 0x80
36682b81 ZJ	47	#define AUTO_CONFIG_CTRL_ADDR 0x7b
	48	#define AUTO_CONFIG_USL_ADDR 0x7d
	49	#define AUTO_CONFIG_LSL_ADDR 0x7e
	50	#define AUTO_CONFIG_TL_ADDR 0x7f
	51
	52	/* Threshold of touch/release trigger */
c7b4a5d5 JZ	53	#define TOUCH_THRESHOLD 0x08
c7b4a5d5 JZ	54	#define RELEASE_THRESHOLD 0x05
36682b81 ZJ	55	/* Masks for touch and release triggers */
	56	#define TOUCH_STATUS_MASK 0xfff
	57	/* MPR121 has 12 keys */
	58	#define MPR121_MAX_KEY_COUNT 12
	59
	60	struct mpr121_touchkey {
	61	struct i2c_client *client;
	62	struct input_dev *input_dev;
	63	unsigned int key_val;
	64	unsigned int statusbits;
	65	unsigned int keycount;
	66	u16 keycodes[MPR121_MAX_KEY_COUNT];
	67	};
	68
	69	struct mpr121_init_register {
	70	int addr;
	71	u8 val;
	72	};
	73
78f50c24	74	static const struct mpr121_init_register init_reg_table[] = {
36682b81 ZJ	75	{ MHD_RISING_ADDR, 0x1 },
	76	{ NHD_RISING_ADDR, 0x1 },
	77	{ MHD_FALLING_ADDR, 0x1 },
	78	{ NHD_FALLING_ADDR, 0x1 },
	79	{ NCL_FALLING_ADDR, 0xff },
	80	{ FDL_FALLING_ADDR, 0x02 },
	81	{ FILTER_CONF_ADDR, 0x04 },
	82	{ AFE_CONF_ADDR, 0x0b },
	83	{ AUTO_CONFIG_CTRL_ADDR, 0x0b },
	84	};
	85
	86	static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
	87	{
	88	struct mpr121_touchkey *mpr121 = dev_id;
	89	struct i2c_client *client = mpr121->client;
	90	struct input_dev *input = mpr121->input_dev;
39106815 AM	91	unsigned long bit_changed;
39106815 AM	92	unsigned int key_num;
36682b81 ZJ	93	int reg;
	94
	95	reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
	96	if (reg < 0) {
	97	dev_err(&client->dev, "i2c read error [%d]\n", reg);
	98	goto out;
	99	}
	100
	101	reg <<= 8;
	102	reg \|= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
	103	if (reg < 0) {
	104	dev_err(&client->dev, "i2c read error [%d]\n", reg);
	105	goto out;
	106	}
	107
	108	reg &= TOUCH_STATUS_MASK;
	109	/* use old press bit to figure out which bit changed */
39106815	110	bit_changed = reg ^ mpr121->statusbits;
36682b81	111	mpr121->statusbits = reg;
39106815 AM	112	for_each_set_bit(key_num, &bit_changed, mpr121->keycount) {
39106815 AM	113	unsigned int key_val, pressed;
36682b81	114
39106815 AM	115	pressed = reg & BIT(key_num);
39106815 AM	116	key_val = mpr121->keycodes[key_num];
36682b81	117
39106815 AM	118	input_event(input, EV_MSC, MSC_SCAN, key_num);
	119	input_report_key(input, key_val, pressed);
	120
	121	dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
	122	pressed ? "pressed" : "released");
36682b81	123
39106815 AM	124	}
39106815 AM	125	input_sync(input);
36682b81 ZJ	126
	127	out:
	128	return IRQ_HANDLED;
	129	}
	130
5298cc4c	131	static int mpr121_phys_init(const struct mpr121_platform_data *pdata,
36682b81 ZJ	132	struct mpr121_touchkey *mpr121,
	133	struct i2c_client *client)
	134	{
	135	const struct mpr121_init_register *reg;
c7b4a5d5	136	unsigned char usl, lsl, tl, eleconf;
36682b81 ZJ	137	int i, t, vdd, ret;
	138
	139	/* Set up touch/release threshold for ele0-ele11 */
	140	for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
	141	t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
	142	ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
	143	if (ret < 0)
	144	goto err_i2c_write;
	145	ret = i2c_smbus_write_byte_data(client, t + 1,
	146	RELEASE_THRESHOLD);
	147	if (ret < 0)
	148	goto err_i2c_write;
	149	}
	150
	151	/* Set up init register */
	152	for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
	153	reg = &init_reg_table[i];
	154	ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
	155	if (ret < 0)
	156	goto err_i2c_write;
	157	}
	158
	159
	160	/*
	161	* Capacitance on sensing input varies and needs to be compensated.
	162	* The internal MPR121-auto-configuration can do this if it's
	163	* registers are set properly (based on pdata->vdd_uv).
	164	*/
	165	vdd = pdata->vdd_uv / 1000;
	166	usl = ((vdd - 700) * 256) / vdd;
	167	lsl = (usl * 65) / 100;
	168	tl = (usl * 90) / 100;
	169	ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
	170	ret \|= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
	171	ret \|= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);
c7b4a5d5 JZ	172
	173	/*
	174	* Quick charge bit will let the capacitive charge to ready
	175	* state quickly, or the buttons may not function after system
	176	* boot.
	177	*/
	178	eleconf = mpr121->keycount \| ELECTRODE_CONF_QUICK_CHARGE;
36682b81	179	ret \|= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
c7b4a5d5	180	eleconf);
36682b81 ZJ	181	if (ret != 0)
	182	goto err_i2c_write;
	183
	184	dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);
	185
	186	return 0;
	187
	188	err_i2c_write:
	189	dev_err(&client->dev, "i2c write error: %d\n", ret);
	190	return ret;
	191	}
	192
5298cc4c BP	193	static int mpr_touchkey_probe(struct i2c_client *client,
5298cc4c BP	194	const struct i2c_device_id *id)
36682b81 ZJ	195	{
	196	const struct mpr121_platform_data *pdata = client->dev.platform_data;
	197	struct mpr121_touchkey *mpr121;
	198	struct input_dev *input_dev;
	199	int error;
	200	int i;
	201
	202	if (!pdata) {
	203	dev_err(&client->dev, "no platform data defined\n");
	204	return -EINVAL;
	205	}
	206
	207	if (!pdata->keymap \|\| !pdata->keymap_size) {
	208	dev_err(&client->dev, "missing keymap data\n");
	209	return -EINVAL;
	210	}
	211
	212	if (pdata->keymap_size > MPR121_MAX_KEY_COUNT) {
	213	dev_err(&client->dev, "too many keys defined\n");
	214	return -EINVAL;
	215	}
	216
	217	if (!client->irq) {
	218	dev_err(&client->dev, "irq number should not be zero\n");
	219	return -EINVAL;
	220	}
	221
	222	mpr121 = kzalloc(sizeof(struct mpr121_touchkey), GFP_KERNEL);
	223	input_dev = input_allocate_device();
	224	if (!mpr121 \|\| !input_dev) {
	225	dev_err(&client->dev, "Failed to allocate memory\n");
	226	error = -ENOMEM;
	227	goto err_free_mem;
	228	}
	229
	230	mpr121->client = client;
	231	mpr121->input_dev = input_dev;
	232	mpr121->keycount = pdata->keymap_size;
	233
	234	input_dev->name = "Freescale MPR121 Touchkey";
	235	input_dev->id.bustype = BUS_I2C;
	236	input_dev->dev.parent = &client->dev;
	237	input_dev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_REP);
091db526	238	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
36682b81 ZJ	239
	240	input_dev->keycode = mpr121->keycodes;
	241	input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
	242	input_dev->keycodemax = mpr121->keycount;
	243
	244	for (i = 0; i < pdata->keymap_size; i++) {
	245	input_set_capability(input_dev, EV_KEY, pdata->keymap[i]);
	246	mpr121->keycodes[i] = pdata->keymap[i];
	247	}
	248
	249	error = mpr121_phys_init(pdata, mpr121, client);
	250	if (error) {
	251	dev_err(&client->dev, "Failed to init register\n");
	252	goto err_free_mem;
	253	}
	254
	255	error = request_threaded_irq(client->irq, NULL,
	256	mpr_touchkey_interrupt,
9b7e31bb	257	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
36682b81 ZJ	258	client->dev.driver->name, mpr121);
	259	if (error) {
	260	dev_err(&client->dev, "Failed to register interrupt\n");
	261	goto err_free_mem;
	262	}
	263
	264	error = input_register_device(input_dev);
	265	if (error)
	266	goto err_free_irq;
	267
	268	i2c_set_clientdata(client, mpr121);
	269	device_init_wakeup(&client->dev, pdata->wakeup);
	270
	271	return 0;
	272
	273	err_free_irq:
	274	free_irq(client->irq, mpr121);
	275	err_free_mem:
	276	input_free_device(input_dev);
	277	kfree(mpr121);
	278	return error;
	279	}
	280
e2619cf7	281	static int mpr_touchkey_remove(struct i2c_client *client)
36682b81 ZJ	282	{
	283	struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
	284
	285	free_irq(client->irq, mpr121);
	286	input_unregister_device(mpr121->input_dev);
	287	kfree(mpr121);
	288
	289	return 0;
	290	}
	291
	292	#ifdef CONFIG_PM_SLEEP
	293	static int mpr_suspend(struct device *dev)
	294	{
	295	struct i2c_client *client = to_i2c_client(dev);
	296
	297	if (device_may_wakeup(&client->dev))
	298	enable_irq_wake(client->irq);
	299
	300	i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);
	301
	302	return 0;
	303	}
	304
	305	static int mpr_resume(struct device *dev)
	306	{
	307	struct i2c_client *client = to_i2c_client(dev);
	308	struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
	309
	310	if (device_may_wakeup(&client->dev))
	311	disable_irq_wake(client->irq);
	312
	313	i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
	314	mpr121->keycount);
	315
	316	return 0;
	317	}
	318	#endif
	319
	320	static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);
	321
	322	static const struct i2c_device_id mpr121_id[] = {
	323	{ "mpr121_touchkey", 0 },
	324	{ }
	325	};
	326	MODULE_DEVICE_TABLE(i2c, mpr121_id);
	327
	328	static struct i2c_driver mpr_touchkey_driver = {
	329	.driver = {
	330	.name = "mpr121",
	331	.owner = THIS_MODULE,
	332	.pm = &mpr121_touchkey_pm_ops,
	333	},
	334	.id_table = mpr121_id,
	335	.probe = mpr_touchkey_probe,
1cb0aa88	336	.remove = mpr_touchkey_remove,
36682b81 ZJ	337	};
36682b81 ZJ	338
1b92c1cf	339	module_i2c_driver(mpr_touchkey_driver);
36682b81 ZJ	340
	341	MODULE_LICENSE("GPL");
	342	MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
	343	MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");