[deliverable/linux.git] / drivers / input / touchscreen / ad7879.c

/*
 * AD7879/AD7889 based touchscreen and GPIO driver
 *
 * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 *
 * History:
 * Copyright (c) 2005 David Brownell
 * Copyright (c) 2006 Nokia Corporation
 * Various changes: Imre Deak <imre.deak@nokia.com>
 *
 * Using code from:
 *  - corgi_ts.c
 *	Copyright (C) 2004-2005 Richard Purdie
 *  - omap_ts.[hc], ads7846.h, ts_osk.c
 *	Copyright (C) 2002 MontaVista Software
 *	Copyright (C) 2004 Texas Instruments
 *	Copyright (C) 2005 Dirk Behme
 *  - ad7877.c
 *	Copyright (C) 2006-2008 Analog Devices Inc.
 */

#include <linux/device.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/i2c.h>
#include <linux/gpio.h>

#include <linux/spi/ad7879.h>
#include "ad7879.h"

#define AD7879_REG_ZEROS		0
#define AD7879_REG_CTRL1		1
#define AD7879_REG_CTRL2		2
#define AD7879_REG_CTRL3		3
#define AD7879_REG_AUX1HIGH		4
#define AD7879_REG_AUX1LOW		5
#define AD7879_REG_TEMP1HIGH		6
#define AD7879_REG_TEMP1LOW		7
#define AD7879_REG_XPLUS		8
#define AD7879_REG_YPLUS		9
#define AD7879_REG_Z1			10
#define AD7879_REG_Z2			11
#define AD7879_REG_AUXVBAT		12
#define AD7879_REG_TEMP			13
#define AD7879_REG_REVID		14

/* Control REG 1 */
#define AD7879_TMR(x)			((x & 0xFF) << 0)
#define AD7879_ACQ(x)			((x & 0x3) << 8)
#define AD7879_MODE_NOC			(0 << 10)	/* Do not convert */
#define AD7879_MODE_SCC			(1 << 10)	/* Single channel conversion */
#define AD7879_MODE_SEQ0		(2 << 10)	/* Sequence 0 in Slave Mode */
#define AD7879_MODE_SEQ1		(3 << 10)	/* Sequence 1 in Master Mode */
#define AD7879_MODE_INT			(1 << 15)	/* PENIRQ disabled INT enabled */

/* Control REG 2 */
#define AD7879_FCD(x)			((x & 0x3) << 0)
#define AD7879_RESET			(1 << 4)
#define AD7879_MFS(x)			((x & 0x3) << 5)
#define AD7879_AVG(x)			((x & 0x3) << 7)
#define	AD7879_SER			(1 << 9)	/* non-differential */
#define	AD7879_DFR			(0 << 9)	/* differential */
#define AD7879_GPIOPOL			(1 << 10)
#define AD7879_GPIODIR			(1 << 11)
#define AD7879_GPIO_DATA		(1 << 12)
#define AD7879_GPIO_EN			(1 << 13)
#define AD7879_PM(x)			((x & 0x3) << 14)
#define AD7879_PM_SHUTDOWN		(0)
#define AD7879_PM_DYN			(1)
#define AD7879_PM_FULLON		(2)

/* Control REG 3 */
#define AD7879_TEMPMASK_BIT		(1<<15)
#define AD7879_AUXVBATMASK_BIT		(1<<14)
#define AD7879_INTMODE_BIT		(1<<13)
#define AD7879_GPIOALERTMASK_BIT	(1<<12)
#define AD7879_AUXLOW_BIT		(1<<11)
#define AD7879_AUXHIGH_BIT		(1<<10)
#define AD7879_TEMPLOW_BIT		(1<<9)
#define AD7879_TEMPHIGH_BIT		(1<<8)
#define AD7879_YPLUS_BIT		(1<<7)
#define AD7879_XPLUS_BIT		(1<<6)
#define AD7879_Z1_BIT			(1<<5)
#define AD7879_Z2_BIT			(1<<4)
#define AD7879_AUX_BIT			(1<<3)
#define AD7879_VBAT_BIT			(1<<2)
#define AD7879_TEMP_BIT			(1<<1)

enum {
	AD7879_SEQ_XPOS  = 0,
	AD7879_SEQ_YPOS  = 1,
	AD7879_SEQ_Z1    = 2,
	AD7879_SEQ_Z2    = 3,
	AD7879_NR_SENSE  = 4,
};

#define	MAX_12BIT			((1<<12)-1)
#define	TS_PEN_UP_TIMEOUT		msecs_to_jiffies(50)

struct ad7879 {
	const struct ad7879_bus_ops *bops;

	struct device		*dev;
	struct input_dev	*input;
	struct timer_list	timer;
#ifdef CONFIG_GPIOLIB
	struct gpio_chip	gc;
	struct mutex		mutex;
#endif
	unsigned int		irq;
	bool			disabled;	/* P: input->mutex */
	bool			suspended;	/* P: input->mutex */
	u16			conversion_data[AD7879_NR_SENSE];
	char			phys[32];
	u8			first_conversion_delay;
	u8			acquisition_time;
	u8			averaging;
	u8			pen_down_acc_interval;
	u8			median;
	u16			x_plate_ohms;
	u16			pressure_max;
	u16			cmd_crtl1;
	u16			cmd_crtl2;
	u16			cmd_crtl3;
	int			x;
	int			y;
	int			Rt;
};

static int ad7879_read(struct ad7879 *ts, u8 reg)
{
	return ts->bops->read(ts->dev, reg);
}

static int ad7879_multi_read(struct ad7879 *ts, u8 first_reg, u8 count, u16 *buf)
{
	return ts->bops->multi_read(ts->dev, first_reg, count, buf);
}

static int ad7879_write(struct ad7879 *ts, u8 reg, u16 val)
{
	return ts->bops->write(ts->dev, reg, val);
}

static int ad7879_report(struct ad7879 *ts)
{
	struct input_dev *input_dev = ts->input;
	unsigned Rt;
	u16 x, y, z1, z2;

	x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT;
	y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT;
	z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT;
	z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT;

	/*
	 * The samples processed here are already preprocessed by the AD7879.
	 * The preprocessing function consists of a median and an averaging
	 * filter.  The combination of these two techniques provides a robust
	 * solution, discarding the spurious noise in the signal and keeping
	 * only the data of interest.  The size of both filters is
	 * programmable. (dev.platform_data, see linux/spi/ad7879.h) Other
	 * user-programmable conversion controls include variable acquisition
	 * time, and first conversion delay. Up to 16 averages can be taken
	 * per conversion.
	 */

	if (likely(x && z1)) {
		/* compute touch pressure resistance using equation #1 */
		Rt = (z2 - z1) * x * ts->x_plate_ohms;
		Rt /= z1;
		Rt = (Rt + 2047) >> 12;

		/*
		 * Sample found inconsistent, pressure is beyond
		 * the maximum. Don't report it to user space.
		 */
		if (Rt > ts->pressure_max)
			return -EINVAL;

		/*
		 * Note that we delay reporting events by one sample.
		 * This is done to avoid reporting last sample of the
		 * touch sequence, which may be incomplete if finger
		 * leaves the surface before last reading is taken.
		 */
		if (timer_pending(&ts->timer)) {
			/* Touch continues */
			input_report_key(input_dev, BTN_TOUCH, 1);
			input_report_abs(input_dev, ABS_X, ts->x);
			input_report_abs(input_dev, ABS_Y, ts->y);
			input_report_abs(input_dev, ABS_PRESSURE, ts->Rt);
			input_sync(input_dev);
		}

		ts->x = x;
		ts->y = y;
		ts->Rt = Rt;

		return 0;
	}

	return -EINVAL;
}

static void ad7879_ts_event_release(struct ad7879 *ts)
{
	struct input_dev *input_dev = ts->input;

	input_report_abs(input_dev, ABS_PRESSURE, 0);
	input_report_key(input_dev, BTN_TOUCH, 0);
	input_sync(input_dev);
}

static void ad7879_timer(unsigned long handle)
{
	struct ad7879 *ts = (void *)handle;

	ad7879_ts_event_release(ts);
}

static irqreturn_t ad7879_irq(int irq, void *handle)
{
	struct ad7879 *ts = handle;

	ad7879_multi_read(ts, AD7879_REG_XPLUS, AD7879_NR_SENSE, ts->conversion_data);

	if (!ad7879_report(ts))
		mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);

	return IRQ_HANDLED;
}

static void __ad7879_enable(struct ad7879 *ts)
{
	ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
	ad7879_write(ts, AD7879_REG_CTRL3, ts->cmd_crtl3);
	ad7879_write(ts, AD7879_REG_CTRL1, ts->cmd_crtl1);

	enable_irq(ts->irq);
}

static void __ad7879_disable(struct ad7879 *ts)
{
	u16 reg = (ts->cmd_crtl2 & ~AD7879_PM(-1)) |
		AD7879_PM(AD7879_PM_SHUTDOWN);
	disable_irq(ts->irq);

	if (del_timer_sync(&ts->timer))
		ad7879_ts_event_release(ts);

	ad7879_write(ts, AD7879_REG_CTRL2, reg);
}


static int ad7879_open(struct input_dev *input)
{
	struct ad7879 *ts = input_get_drvdata(input);

	/* protected by input->mutex */
	if (!ts->disabled && !ts->suspended)
		__ad7879_enable(ts);

	return 0;
}

static void ad7879_close(struct input_dev* input)
{
	struct ad7879 *ts = input_get_drvdata(input);

	/* protected by input->mutex */
	if (!ts->disabled && !ts->suspended)
		__ad7879_disable(ts);
}

void ad7879_suspend(struct ad7879 *ts)
{
	mutex_lock(&ts->input->mutex);

	if (!ts->suspended && !ts->disabled && ts->input->users)
		__ad7879_disable(ts);

	ts->suspended = true;

	mutex_unlock(&ts->input->mutex);
}
EXPORT_SYMBOL(ad7879_suspend);

void ad7879_resume(struct ad7879 *ts)
{
	mutex_lock(&ts->input->mutex);

	if (ts->suspended && !ts->disabled && ts->input->users)
		__ad7879_enable(ts);

	ts->suspended = false;

	mutex_unlock(&ts->input->mutex);
}
EXPORT_SYMBOL(ad7879_resume);

static void ad7879_toggle(struct ad7879 *ts, bool disable)
{
	mutex_lock(&ts->input->mutex);

	if (!ts->suspended && ts->input->users != 0) {

		if (disable) {
			if (ts->disabled)
				__ad7879_enable(ts);
		} else {
			if (!ts->disabled)
				__ad7879_disable(ts);
		}
	}

	ts->disabled = disable;

	mutex_unlock(&ts->input->mutex);
}

static ssize_t ad7879_disable_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{
	struct ad7879 *ts = dev_get_drvdata(dev);

	return sprintf(buf, "%u\n", ts->disabled);
}

static ssize_t ad7879_disable_store(struct device *dev,
				     struct device_attribute *attr,
				     const char *buf, size_t count)
{
	struct ad7879 *ts = dev_get_drvdata(dev);
	unsigned long val;
	int error;

	error = strict_strtoul(buf, 10, &val);
	if (error)
		return error;

	ad7879_toggle(ts, val);

	return count;
}

static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store);

static struct attribute *ad7879_attributes[] = {
	&dev_attr_disable.attr,
	NULL
};

static const struct attribute_group ad7879_attr_group = {
	.attrs = ad7879_attributes,
};

#ifdef CONFIG_GPIOLIB
static int ad7879_gpio_direction_input(struct gpio_chip *chip,
					unsigned gpio)
{
	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
	int err;

	mutex_lock(&ts->mutex);
	ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIODIR | AD7879_GPIOPOL;
	err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
	mutex_unlock(&ts->mutex);

	return err;
}

static int ad7879_gpio_direction_output(struct gpio_chip *chip,
					unsigned gpio, int level)
{
	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
	int err;

	mutex_lock(&ts->mutex);
	ts->cmd_crtl2 &= ~AD7879_GPIODIR;
	ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIOPOL;
	if (level)
		ts->cmd_crtl2 |= AD7879_GPIO_DATA;
	else
		ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;

	err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
	mutex_unlock(&ts->mutex);

	return err;
}

static int ad7879_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
	u16 val;

	mutex_lock(&ts->mutex);
	val = ad7879_read(ts, AD7879_REG_CTRL2);
	mutex_unlock(&ts->mutex);

	return !!(val & AD7879_GPIO_DATA);
}

static void ad7879_gpio_set_value(struct gpio_chip *chip,
				  unsigned gpio, int value)
{
	struct ad7879 *ts = container_of(chip, struct ad7879, gc);

	mutex_lock(&ts->mutex);
	if (value)
		ts->cmd_crtl2 |= AD7879_GPIO_DATA;
	else
		ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;

	ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
	mutex_unlock(&ts->mutex);
}

static int ad7879_gpio_add(struct ad7879 *ts,
			   const struct ad7879_platform_data *pdata)
{
	int ret = 0;

	mutex_init(&ts->mutex);

	if (pdata->gpio_export) {
		ts->gc.direction_input = ad7879_gpio_direction_input;
		ts->gc.direction_output = ad7879_gpio_direction_output;
		ts->gc.get = ad7879_gpio_get_value;
		ts->gc.set = ad7879_gpio_set_value;
		ts->gc.can_sleep = 1;
		ts->gc.base = pdata->gpio_base;
		ts->gc.ngpio = 1;
		ts->gc.label = "AD7879-GPIO";
		ts->gc.owner = THIS_MODULE;
		ts->gc.dev = ts->dev;

		ret = gpiochip_add(&ts->gc);
		if (ret)
			dev_err(ts->dev, "failed to register gpio %d\n",
				ts->gc.base);
	}

	return ret;
}

static void ad7879_gpio_remove(struct ad7879 *ts)
{
	const struct ad7879_platform_data *pdata = ts->dev->platform_data;
	int ret;

	if (pdata->gpio_export) {
		ret = gpiochip_remove(&ts->gc);
		if (ret)
			dev_err(ts->dev, "failed to remove gpio %d\n",
				ts->gc.base);
	}
}
#else
static inline int ad7879_gpio_add(struct ad7879 *ts,
				  const struct ad7879_platform_data *pdata)
{
	return 0;
}

static inline void ad7879_gpio_remove(struct ad7879 *ts)
{
}
#endif

struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
			    const struct ad7879_bus_ops *bops)
{
	struct ad7879_platform_data *pdata = dev->platform_data;
	struct ad7879 *ts;
	struct input_dev *input_dev;
	int err;
	u16 revid;

	if (!irq) {
		dev_err(dev, "no IRQ?\n");
		err = -EINVAL;
		goto err_out;
	}

	if (!pdata) {
		dev_err(dev, "no platform data?\n");
		err = -EINVAL;
		goto err_out;
	}

	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!ts || !input_dev) {
		err = -ENOMEM;
		goto err_free_mem;
	}

	ts->bops = bops;
	ts->dev = dev;
	ts->input = input_dev;
	ts->irq = irq;

	setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);

	ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
	ts->pressure_max = pdata->pressure_max ? : ~0;

	ts->first_conversion_delay = pdata->first_conversion_delay;
	ts->acquisition_time = pdata->acquisition_time;
	ts->averaging = pdata->averaging;
	ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
	ts->median = pdata->median;

	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));

	input_dev->name = "AD7879 Touchscreen";
	input_dev->phys = ts->phys;
	input_dev->dev.parent = dev;
	input_dev->id.bustype = bops->bustype;

	input_dev->open = ad7879_open;
	input_dev->close = ad7879_close;

	input_set_drvdata(input_dev, ts);

	__set_bit(EV_ABS, input_dev->evbit);
	__set_bit(ABS_X, input_dev->absbit);
	__set_bit(ABS_Y, input_dev->absbit);
	__set_bit(ABS_PRESSURE, input_dev->absbit);

	__set_bit(EV_KEY, input_dev->evbit);
	__set_bit(BTN_TOUCH, input_dev->keybit);

	input_set_abs_params(input_dev, ABS_X,
			pdata->x_min ? : 0,
			pdata->x_max ? : MAX_12BIT,
			0, 0);
	input_set_abs_params(input_dev, ABS_Y,
			pdata->y_min ? : 0,
			pdata->y_max ? : MAX_12BIT,
			0, 0);
	input_set_abs_params(input_dev, ABS_PRESSURE,
			pdata->pressure_min, pdata->pressure_max, 0, 0);

	err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
	if (err < 0) {
		dev_err(dev, "Failed to write %s\n", input_dev->name);
		goto err_free_mem;
	}

	revid = ad7879_read(ts, AD7879_REG_REVID);
	input_dev->id.product = (revid & 0xff);
	input_dev->id.version = revid >> 8;
	if (input_dev->id.product != devid) {
		dev_err(dev, "Failed to probe %s (%x vs %x)\n",
			input_dev->name, devid, revid);
		err = -ENODEV;
		goto err_free_mem;
	}

	ts->cmd_crtl3 = AD7879_YPLUS_BIT |
			AD7879_XPLUS_BIT |
			AD7879_Z2_BIT |
			AD7879_Z1_BIT |
			AD7879_TEMPMASK_BIT |
			AD7879_AUXVBATMASK_BIT |
			AD7879_GPIOALERTMASK_BIT;

	ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR |
			AD7879_AVG(ts->averaging) |
			AD7879_MFS(ts->median) |
			AD7879_FCD(ts->first_conversion_delay);

	ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 |
			AD7879_ACQ(ts->acquisition_time) |
			AD7879_TMR(ts->pen_down_acc_interval);

	err = request_threaded_irq(ts->irq, NULL, ad7879_irq,
				   IRQF_TRIGGER_FALLING,
				   dev_name(dev), ts);
	if (err) {
		dev_err(dev, "irq %d busy?\n", ts->irq);
		goto err_free_mem;
	}

	__ad7879_disable(ts);

	err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
	if (err)
		goto err_free_irq;

	err = ad7879_gpio_add(ts, pdata);
	if (err)
		goto err_remove_attr;

	err = input_register_device(input_dev);
	if (err)
		goto err_remove_gpio;

	return ts;

err_remove_gpio:
	ad7879_gpio_remove(ts);
err_remove_attr:
	sysfs_remove_group(&dev->kobj, &ad7879_attr_group);
err_free_irq:
	free_irq(ts->irq, ts);
err_free_mem:
	input_free_device(input_dev);
	kfree(ts);
err_out:
	return ERR_PTR(err);
}
EXPORT_SYMBOL(ad7879_probe);

void ad7879_remove(struct ad7879 *ts)
{
	ad7879_gpio_remove(ts);
	sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
	free_irq(ts->irq, ts);
	input_unregister_device(ts->input);
	kfree(ts);
}
EXPORT_SYMBOL(ad7879_remove);

MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
b4be468c	1	/*
4397c98a	2	* AD7879/AD7889 based touchscreen and GPIO driver
b4be468c	3	*
4397c98a	4	* Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
b4be468c	5	*
4397c98a	6	* Licensed under the GPL-2 or later.
b4be468c MH	7	*
	8	* History:
	9	* Copyright (c) 2005 David Brownell
	10	* Copyright (c) 2006 Nokia Corporation
	11	* Various changes: Imre Deak <imre.deak@nokia.com>
	12	*
	13	* Using code from:
	14	* - corgi_ts.c
	15	* Copyright (C) 2004-2005 Richard Purdie
	16	* - omap_ts.[hc], ads7846.h, ts_osk.c
	17	* Copyright (C) 2002 MontaVista Software
	18	* Copyright (C) 2004 Texas Instruments
	19	* Copyright (C) 2005 Dirk Behme
	20	* - ad7877.c
	21	* Copyright (C) 2006-2008 Analog Devices Inc.
	22	*/
	23
	24	#include <linux/device.h>
	25	#include <linux/init.h>
	26	#include <linux/delay.h>
	27	#include <linux/input.h>
	28	#include <linux/interrupt.h>
	29	#include <linux/irq.h>
	30	#include <linux/slab.h>
b4be468c MH	31	#include <linux/spi/spi.h>
b4be468c MH	32	#include <linux/i2c.h>
ec51b7f5	33	#include <linux/gpio.h>
b4be468c MH	34
b4be468c MH	35	#include <linux/spi/ad7879.h>
4397c98a	36	#include "ad7879.h"
b4be468c MH	37
	38	#define AD7879_REG_ZEROS 0
	39	#define AD7879_REG_CTRL1 1
	40	#define AD7879_REG_CTRL2 2
	41	#define AD7879_REG_CTRL3 3
	42	#define AD7879_REG_AUX1HIGH 4
	43	#define AD7879_REG_AUX1LOW 5
	44	#define AD7879_REG_TEMP1HIGH 6
	45	#define AD7879_REG_TEMP1LOW 7
	46	#define AD7879_REG_XPLUS 8
	47	#define AD7879_REG_YPLUS 9
	48	#define AD7879_REG_Z1 10
	49	#define AD7879_REG_Z2 11
	50	#define AD7879_REG_AUXVBAT 12
	51	#define AD7879_REG_TEMP 13
	52	#define AD7879_REG_REVID 14
	53
	54	/* Control REG 1 */
	55	#define AD7879_TMR(x) ((x & 0xFF) << 0)
	56	#define AD7879_ACQ(x) ((x & 0x3) << 8)
	57	#define AD7879_MODE_NOC (0 << 10) /* Do not convert */
	58	#define AD7879_MODE_SCC (1 << 10) /* Single channel conversion */
	59	#define AD7879_MODE_SEQ0 (2 << 10) /* Sequence 0 in Slave Mode */
	60	#define AD7879_MODE_SEQ1 (3 << 10) /* Sequence 1 in Master Mode */
	61	#define AD7879_MODE_INT (1 << 15) /* PENIRQ disabled INT enabled */
	62
	63	/* Control REG 2 */
	64	#define AD7879_FCD(x) ((x & 0x3) << 0)
	65	#define AD7879_RESET (1 << 4)
	66	#define AD7879_MFS(x) ((x & 0x3) << 5)
	67	#define AD7879_AVG(x) ((x & 0x3) << 7)
	68	#define AD7879_SER (1 << 9) /* non-differential */
	69	#define AD7879_DFR (0 << 9) /* differential */
	70	#define AD7879_GPIOPOL (1 << 10)
	71	#define AD7879_GPIODIR (1 << 11)
	72	#define AD7879_GPIO_DATA (1 << 12)
	73	#define AD7879_GPIO_EN (1 << 13)
	74	#define AD7879_PM(x) ((x & 0x3) << 14)
	75	#define AD7879_PM_SHUTDOWN (0)
	76	#define AD7879_PM_DYN (1)
	77	#define AD7879_PM_FULLON (2)
	78
	79	/* Control REG 3 */
	80	#define AD7879_TEMPMASK_BIT (1<<15)
	81	#define AD7879_AUXVBATMASK_BIT (1<<14)
	82	#define AD7879_INTMODE_BIT (1<<13)
	83	#define AD7879_GPIOALERTMASK_BIT (1<<12)
	84	#define AD7879_AUXLOW_BIT (1<<11)
	85	#define AD7879_AUXHIGH_BIT (1<<10)
	86	#define AD7879_TEMPLOW_BIT (1<<9)
	87	#define AD7879_TEMPHIGH_BIT (1<<8)
	88	#define AD7879_YPLUS_BIT (1<<7)
	89	#define AD7879_XPLUS_BIT (1<<6)
	90	#define AD7879_Z1_BIT (1<<5)
	91	#define AD7879_Z2_BIT (1<<4)
	92	#define AD7879_AUX_BIT (1<<3)
	93	#define AD7879_VBAT_BIT (1<<2)
	94	#define AD7879_TEMP_BIT (1<<1)
	95
	96	enum {
	97	AD7879_SEQ_XPOS = 0,
	98	AD7879_SEQ_YPOS = 1,
	99	AD7879_SEQ_Z1 = 2,
	100	AD7879_SEQ_Z2 = 3,
101	AD7879_NR_SENSE = 4,
102	};
103
104	#define MAX_12BIT ((1<<12)-1)
105	#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50)
106
b4be468c	107	struct ad7879 {
4397c98a MF	108	const struct ad7879_bus_ops *bops;
	109
	110	struct device *dev;
b4be468c	111	struct input_dev *input;
b4be468c	112	struct timer_list timer;
ec51b7f5 MH	113	#ifdef CONFIG_GPIOLIB
ec51b7f5 MH	114	struct gpio_chip gc;
14fbbc36	115	struct mutex mutex;
ec51b7f5	116	#endif
4397c98a	117	unsigned int irq;
14fbbc36 DT	118	bool disabled; /* P: input->mutex */
14fbbc36 DT	119	bool suspended; /* P: input->mutex */
b4be468c MH	120	u16 conversion_data[AD7879_NR_SENSE];
	121	char phys[32];
	122	u8 first_conversion_delay;
	123	u8 acquisition_time;
	124	u8 averaging;
	125	u8 pen_down_acc_interval;
	126	u8 median;
	127	u16 x_plate_ohms;
	128	u16 pressure_max;
b4be468c MH	129	u16 cmd_crtl1;
	130	u16 cmd_crtl2;
	131	u16 cmd_crtl3;
b584efc9 MH	132	int x;
	133	int y;
	134	int Rt;
b4be468c MH	135	};
b4be468c MH	136
4397c98a MF	137	static int ad7879_read(struct ad7879 *ts, u8 reg)
	138	{
	139	return ts->bops->read(ts->dev, reg);
	140	}
	141
	142	static int ad7879_multi_read(struct ad7879 ts, u8 first_reg, u8 count, u16 buf)
	143	{
	144	return ts->bops->multi_read(ts->dev, first_reg, count, buf);
	145	}
	146
	147	static int ad7879_write(struct ad7879 *ts, u8 reg, u16 val)
	148	{
	149	return ts->bops->write(ts->dev, reg, val);
	150	}
b4be468c	151
963ce8ae	152	static int ad7879_report(struct ad7879 *ts)
b4be468c MH	153	{
	154	struct input_dev *input_dev = ts->input;
	155	unsigned Rt;
	156	u16 x, y, z1, z2;
	157
	158	x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT;
	159	y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT;
	160	z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT;
	161	z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT;
	162
	163	/*
	164	* The samples processed here are already preprocessed by the AD7879.
4397c98a MF	165	* The preprocessing function consists of a median and an averaging
	166	* filter. The combination of these two techniques provides a robust
	167	* solution, discarding the spurious noise in the signal and keeping
	168	* only the data of interest. The size of both filters is
	169	* programmable. (dev.platform_data, see linux/spi/ad7879.h) Other
	170	* user-programmable conversion controls include variable acquisition
	171	* time, and first conversion delay. Up to 16 averages can be taken
	172	* per conversion.
b4be468c MH	173	*/
	174
	175	if (likely(x && z1)) {
	176	/* compute touch pressure resistance using equation #1 */
	177	Rt = (z2 - z1) * x * ts->x_plate_ohms;
	178	Rt /= z1;
	179	Rt = (Rt + 2047) >> 12;
	180
b584efc9 MH	181	/*
	182	* Sample found inconsistent, pressure is beyond
	183	* the maximum. Don't report it to user space.
	184	*/
	185	if (Rt > ts->pressure_max)
	186	return -EINVAL;
	187
	188	/*
	189	* Note that we delay reporting events by one sample.
	190	* This is done to avoid reporting last sample of the
	191	* touch sequence, which may be incomplete if finger
	192	* leaves the surface before last reading is taken.
	193	*/
	194	if (timer_pending(&ts->timer)) {
	195	/* Touch continues */
963ce8ae	196	input_report_key(input_dev, BTN_TOUCH, 1);
b584efc9 MH	197	input_report_abs(input_dev, ABS_X, ts->x);
	198	input_report_abs(input_dev, ABS_Y, ts->y);
	199	input_report_abs(input_dev, ABS_PRESSURE, ts->Rt);
	200	input_sync(input_dev);
	201	}
	202
	203	ts->x = x;
	204	ts->y = y;
	205	ts->Rt = Rt;
963ce8ae	206
963ce8ae	207	return 0;
b4be468c	208	}
963ce8ae MH	209
963ce8ae MH	210	return -EINVAL;
b4be468c MH	211	}
b4be468c MH	212
b4be468c MH	213	static void ad7879_ts_event_release(struct ad7879 *ts)
	214	{
	215	struct input_dev *input_dev = ts->input;
	216
	217	input_report_abs(input_dev, ABS_PRESSURE, 0);
963ce8ae	218	input_report_key(input_dev, BTN_TOUCH, 0);
b4be468c MH	219	input_sync(input_dev);
	220	}
	221
	222	static void ad7879_timer(unsigned long handle)
	223	{
	224	struct ad7879 ts = (void )handle;
	225
	226	ad7879_ts_event_release(ts);
	227	}
	228
	229	static irqreturn_t ad7879_irq(int irq, void *handle)
	230	{
	231	struct ad7879 *ts = handle;
	232
4397c98a	233	ad7879_multi_read(ts, AD7879_REG_XPLUS, AD7879_NR_SENSE, ts->conversion_data);
b4be468c	234
963ce8ae MH	235	if (!ad7879_report(ts))
963ce8ae MH	236	mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
b4be468c MH	237
	238	return IRQ_HANDLED;
	239	}
	240
14fbbc36	241	static void __ad7879_enable(struct ad7879 *ts)
b4be468c	242	{
4397c98a MF	243	ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
	244	ad7879_write(ts, AD7879_REG_CTRL3, ts->cmd_crtl3);
	245	ad7879_write(ts, AD7879_REG_CTRL1, ts->cmd_crtl1);
14fbbc36 DT	246
14fbbc36 DT	247	enable_irq(ts->irq);
b4be468c MH	248	}
b4be468c MH	249
14fbbc36	250	static void __ad7879_disable(struct ad7879 *ts)
b4be468c	251	{
4fecc208 MH	252	u16 reg = (ts->cmd_crtl2 & ~AD7879_PM(-1)) \|
4fecc208 MH	253	AD7879_PM(AD7879_PM_SHUTDOWN);
14fbbc36	254	disable_irq(ts->irq);
b4be468c	255
14fbbc36 DT	256	if (del_timer_sync(&ts->timer))
14fbbc36 DT	257	ad7879_ts_event_release(ts);
b4be468c	258
4fecc208	259	ad7879_write(ts, AD7879_REG_CTRL2, reg);
14fbbc36	260	}
b4be468c	261
b4be468c	262
14fbbc36 DT	263	static int ad7879_open(struct input_dev *input)
	264	{
	265	struct ad7879 *ts = input_get_drvdata(input);
b4be468c	266
14fbbc36 DT	267	/* protected by input->mutex */
	268	if (!ts->disabled && !ts->suspended)
	269	__ad7879_enable(ts);
	270
	271	return 0;
b4be468c MH	272	}
b4be468c MH	273
14fbbc36	274	static void ad7879_close(struct input_dev* input)
b4be468c	275	{
14fbbc36 DT	276	struct ad7879 *ts = input_get_drvdata(input);
	277
	278	/* protected by input->mutex */
	279	if (!ts->disabled && !ts->suspended)
	280	__ad7879_disable(ts);
	281	}
	282
	283	void ad7879_suspend(struct ad7879 *ts)
	284	{
	285	mutex_lock(&ts->input->mutex);
	286
	287	if (!ts->suspended && !ts->disabled && ts->input->users)
	288	__ad7879_disable(ts);
	289
	290	ts->suspended = true;
	291
	292	mutex_unlock(&ts->input->mutex);
	293	}
	294	EXPORT_SYMBOL(ad7879_suspend);
	295
	296	void ad7879_resume(struct ad7879 *ts)
	297	{
	298	mutex_lock(&ts->input->mutex);
b4be468c	299
14fbbc36 DT	300	if (ts->suspended && !ts->disabled && ts->input->users)
	301	__ad7879_enable(ts);
	302
	303	ts->suspended = false;
	304
	305	mutex_unlock(&ts->input->mutex);
	306	}
	307	EXPORT_SYMBOL(ad7879_resume);
	308
	309	static void ad7879_toggle(struct ad7879 *ts, bool disable)
	310	{
	311	mutex_lock(&ts->input->mutex);
	312
	313	if (!ts->suspended && ts->input->users != 0) {
	314
	315	if (disable) {
	316	if (ts->disabled)
	317	__ad7879_enable(ts);
	318	} else {
	319	if (!ts->disabled)
	320	__ad7879_disable(ts);
	321	}
b4be468c MH	322	}
b4be468c MH	323
14fbbc36 DT	324	ts->disabled = disable;
	325
	326	mutex_unlock(&ts->input->mutex);
b4be468c MH	327	}
	328
	329	static ssize_t ad7879_disable_show(struct device *dev,
	330	struct device_attribute attr, char buf)
	331	{
	332	struct ad7879 *ts = dev_get_drvdata(dev);
	333
	334	return sprintf(buf, "%u\n", ts->disabled);
	335	}
	336
	337	static ssize_t ad7879_disable_store(struct device *dev,
	338	struct device_attribute *attr,
	339	const char *buf, size_t count)
	340	{
	341	struct ad7879 *ts = dev_get_drvdata(dev);
	342	unsigned long val;
	343	int error;
	344
	345	error = strict_strtoul(buf, 10, &val);
	346	if (error)
	347	return error;
	348
14fbbc36	349	ad7879_toggle(ts, val);
b4be468c MH	350
	351	return count;
	352	}
	353
	354	static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store);
	355
ec51b7f5 MH	356	static struct attribute *ad7879_attributes[] = {
	357	&dev_attr_disable.attr,
	358	NULL
	359	};
	360
	361	static const struct attribute_group ad7879_attr_group = {
	362	.attrs = ad7879_attributes,
	363	};
	364
	365	#ifdef CONFIG_GPIOLIB
	366	static int ad7879_gpio_direction_input(struct gpio_chip *chip,
	367	unsigned gpio)
b4be468c	368	{
ec51b7f5 MH	369	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
ec51b7f5 MH	370	int err;
b4be468c	371
ec51b7f5 MH	372	mutex_lock(&ts->mutex);
ec51b7f5 MH	373	ts->cmd_crtl2 \|= AD7879_GPIO_EN \| AD7879_GPIODIR \| AD7879_GPIOPOL;
4397c98a	374	err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
ec51b7f5 MH	375	mutex_unlock(&ts->mutex);
	376
	377	return err;
b4be468c MH	378	}
b4be468c MH	379
ec51b7f5 MH	380	static int ad7879_gpio_direction_output(struct gpio_chip *chip,
ec51b7f5 MH	381	unsigned gpio, int level)
b4be468c	382	{
ec51b7f5 MH	383	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
ec51b7f5 MH	384	int err;
b4be468c	385
ec51b7f5 MH	386	mutex_lock(&ts->mutex);
	387	ts->cmd_crtl2 &= ~AD7879_GPIODIR;
	388	ts->cmd_crtl2 \|= AD7879_GPIO_EN \| AD7879_GPIOPOL;
	389	if (level)
	390	ts->cmd_crtl2 \|= AD7879_GPIO_DATA;
	391	else
	392	ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
	393
4397c98a	394	err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
ec51b7f5 MH	395	mutex_unlock(&ts->mutex);
	396
	397	return err;
	398	}
	399
	400	static int ad7879_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
	401	{
	402	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
	403	u16 val;
b4be468c MH	404
b4be468c MH	405	mutex_lock(&ts->mutex);
4397c98a	406	val = ad7879_read(ts, AD7879_REG_CTRL2);
b4be468c MH	407	mutex_unlock(&ts->mutex);
b4be468c MH	408
ec51b7f5	409	return !!(val & AD7879_GPIO_DATA);
b4be468c MH	410	}
b4be468c MH	411
ec51b7f5 MH	412	static void ad7879_gpio_set_value(struct gpio_chip *chip,
	413	unsigned gpio, int value)
	414	{
	415	struct ad7879 *ts = container_of(chip, struct ad7879, gc);
b4be468c	416
ec51b7f5 MH	417	mutex_lock(&ts->mutex);
	418	if (value)
	419	ts->cmd_crtl2 \|= AD7879_GPIO_DATA;
	420	else
	421	ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
b4be468c	422
4397c98a	423	ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
ec51b7f5 MH	424	mutex_unlock(&ts->mutex);
	425	}
	426
4397c98a MF	427	static int ad7879_gpio_add(struct ad7879 *ts,
4397c98a MF	428	const struct ad7879_platform_data *pdata)
ec51b7f5	429	{
ec51b7f5 MH	430	int ret = 0;
ec51b7f5 MH	431
14fbbc36 DT	432	mutex_init(&ts->mutex);
14fbbc36 DT	433
ec51b7f5 MH	434	if (pdata->gpio_export) {
	435	ts->gc.direction_input = ad7879_gpio_direction_input;
	436	ts->gc.direction_output = ad7879_gpio_direction_output;
	437	ts->gc.get = ad7879_gpio_get_value;
	438	ts->gc.set = ad7879_gpio_set_value;
	439	ts->gc.can_sleep = 1;
	440	ts->gc.base = pdata->gpio_base;
	441	ts->gc.ngpio = 1;
	442	ts->gc.label = "AD7879-GPIO";
	443	ts->gc.owner = THIS_MODULE;
4397c98a	444	ts->gc.dev = ts->dev;
ec51b7f5 MH	445
	446	ret = gpiochip_add(&ts->gc);
	447	if (ret)
4397c98a	448	dev_err(ts->dev, "failed to register gpio %d\n",
ec51b7f5 MH	449	ts->gc.base);
	450	}
	451
	452	return ret;
	453	}
	454
4397c98a	455	static void ad7879_gpio_remove(struct ad7879 *ts)
ec51b7f5	456	{
4397c98a	457	const struct ad7879_platform_data *pdata = ts->dev->platform_data;
ec51b7f5 MH	458	int ret;
	459
	460	if (pdata->gpio_export) {
	461	ret = gpiochip_remove(&ts->gc);
	462	if (ret)
4397c98a	463	dev_err(ts->dev, "failed to remove gpio %d\n",
ec51b7f5 MH	464	ts->gc.base);
	465	}
	466	}
	467	#else
4397c98a MF	468	static inline int ad7879_gpio_add(struct ad7879 *ts,
4397c98a MF	469	const struct ad7879_platform_data *pdata)
ec51b7f5 MH	470	{
	471	return 0;
	472	}
	473
4397c98a	474	static inline void ad7879_gpio_remove(struct ad7879 *ts)
ec51b7f5 MH	475	{
	476	}
	477	#endif
b4be468c	478
4397c98a MF	479	struct ad7879 ad7879_probe(struct device dev, u8 devid, unsigned int irq,
4397c98a MF	480	const struct ad7879_bus_ops *bops)
b4be468c	481	{
4397c98a MF	482	struct ad7879_platform_data *pdata = dev->platform_data;
4397c98a MF	483	struct ad7879 *ts;
b4be468c	484	struct input_dev *input_dev;
b4be468c MH	485	int err;
	486	u16 revid;
	487
4397c98a MF	488	if (!irq) {
	489	dev_err(dev, "no IRQ?\n");
	490	err = -EINVAL;
	491	goto err_out;
b4be468c MH	492	}
	493
	494	if (!pdata) {
4397c98a MF	495	dev_err(dev, "no platform data?\n");
	496	err = -EINVAL;
	497	goto err_out;
b4be468c MH	498	}
b4be468c MH	499
4397c98a	500	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
b4be468c	501	input_dev = input_allocate_device();
4397c98a MF	502	if (!ts \|\| !input_dev) {
	503	err = -ENOMEM;
	504	goto err_free_mem;
	505	}
b4be468c	506
4397c98a MF	507	ts->bops = bops;
4397c98a MF	508	ts->dev = dev;
b4be468c	509	ts->input = input_dev;
14fbbc36	510	ts->irq = irq;
b4be468c MH	511
b4be468c MH	512	setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);
4397c98a	513
b4be468c MH	514	ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
	515	ts->pressure_max = pdata->pressure_max ? : ~0;
	516
	517	ts->first_conversion_delay = pdata->first_conversion_delay;
	518	ts->acquisition_time = pdata->acquisition_time;
	519	ts->averaging = pdata->averaging;
	520	ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
	521	ts->median = pdata->median;
	522
4397c98a	523	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
b4be468c MH	524
	525	input_dev->name = "AD7879 Touchscreen";
	526	input_dev->phys = ts->phys;
4397c98a MF	527	input_dev->dev.parent = dev;
4397c98a MF	528	input_dev->id.bustype = bops->bustype;
b4be468c	529
14fbbc36 DT	530	input_dev->open = ad7879_open;
	531	input_dev->close = ad7879_close;
	532
	533	input_set_drvdata(input_dev, ts);
	534
b4be468c MH	535	__set_bit(EV_ABS, input_dev->evbit);
	536	__set_bit(ABS_X, input_dev->absbit);
	537	__set_bit(ABS_Y, input_dev->absbit);
	538	__set_bit(ABS_PRESSURE, input_dev->absbit);
	539
963ce8ae MH	540	__set_bit(EV_KEY, input_dev->evbit);
	541	__set_bit(BTN_TOUCH, input_dev->keybit);
	542
b4be468c MH	543	input_set_abs_params(input_dev, ABS_X,
	544	pdata->x_min ? : 0,
	545	pdata->x_max ? : MAX_12BIT,
	546	0, 0);
	547	input_set_abs_params(input_dev, ABS_Y,
	548	pdata->y_min ? : 0,
	549	pdata->y_max ? : MAX_12BIT,
	550	0, 0);
	551	input_set_abs_params(input_dev, ABS_PRESSURE,
	552	pdata->pressure_min, pdata->pressure_max, 0, 0);
	553
4397c98a	554	err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
b4be468c	555	if (err < 0) {
4397c98a	556	dev_err(dev, "Failed to write %s\n", input_dev->name);
b4be468c MH	557	goto err_free_mem;
	558	}
	559
4397c98a MF	560	revid = ad7879_read(ts, AD7879_REG_REVID);
	561	input_dev->id.product = (revid & 0xff);
	562	input_dev->id.version = revid >> 8;
	563	if (input_dev->id.product != devid) {
	564	dev_err(dev, "Failed to probe %s (%x vs %x)\n",
	565	input_dev->name, devid, revid);
b4be468c MH	566	err = -ENODEV;
	567	goto err_free_mem;
	568	}
	569
ec51b7f5 MH	570	ts->cmd_crtl3 = AD7879_YPLUS_BIT \|
	571	AD7879_XPLUS_BIT \|
	572	AD7879_Z2_BIT \|
	573	AD7879_Z1_BIT \|
	574	AD7879_TEMPMASK_BIT \|
	575	AD7879_AUXVBATMASK_BIT \|
	576	AD7879_GPIOALERTMASK_BIT;
	577
	578	ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) \| AD7879_DFR \|
	579	AD7879_AVG(ts->averaging) \|
	580	AD7879_MFS(ts->median) \|
	581	AD7879_FCD(ts->first_conversion_delay);
	582
	583	ts->cmd_crtl1 = AD7879_MODE_INT \| AD7879_MODE_SEQ1 \|
	584	AD7879_ACQ(ts->acquisition_time) \|
	585	AD7879_TMR(ts->pen_down_acc_interval);
	586
4397c98a	587	err = request_threaded_irq(ts->irq, NULL, ad7879_irq,
7cd7a82d	588	IRQF_TRIGGER_FALLING,
4397c98a	589	dev_name(dev), ts);
b4be468c	590	if (err) {
4397c98a	591	dev_err(dev, "irq %d busy?\n", ts->irq);
b4be468c MH	592	goto err_free_mem;
	593	}
	594
14fbbc36 DT	595	__ad7879_disable(ts);
14fbbc36 DT	596
4397c98a	597	err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
b4be468c MH	598	if (err)
	599	goto err_free_irq;
	600
4397c98a	601	err = ad7879_gpio_add(ts, pdata);
b4be468c MH	602	if (err)
	603	goto err_remove_attr;
	604
ec51b7f5 MH	605	err = input_register_device(input_dev);
	606	if (err)
	607	goto err_remove_gpio;
	608
4397c98a	609	return ts;
b4be468c	610
ec51b7f5	611	err_remove_gpio:
4397c98a	612	ad7879_gpio_remove(ts);
b4be468c	613	err_remove_attr:
4397c98a	614	sysfs_remove_group(&dev->kobj, &ad7879_attr_group);
b4be468c	615	err_free_irq:
4397c98a	616	free_irq(ts->irq, ts);
b4be468c MH	617	err_free_mem:
b4be468c MH	618	input_free_device(input_dev);
4397c98a MF	619	kfree(ts);
	620	err_out:
	621	return ERR_PTR(err);
b4be468c	622	}
4397c98a	623	EXPORT_SYMBOL(ad7879_probe);
b4be468c	624
4397c98a	625	void ad7879_remove(struct ad7879 *ts)
b4be468c	626	{
4397c98a	627	ad7879_gpio_remove(ts);
4397c98a MF	628	sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
4397c98a MF	629	free_irq(ts->irq, ts);
b4be468c	630	input_unregister_device(ts->input);
b4be468c	631	kfree(ts);
b4be468c	632	}
4397c98a	633	EXPORT_SYMBOL(ad7879_remove);
b4be468c MH	634
	635	MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
	636	MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver");
	637	MODULE_LICENSE("GPL");