drivers/input/touchscreen/s3c2410_ts.c - kernel/msm-4.19 - Gitiles

 /*
  * Samsung S3C24XX touchscreen driver
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the term 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.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  *
  * Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org>
  * Copyright 2008 Ben Dooks <ben-linux@fluff.org>
  * Copyright 2009 Simtec Electronics <linux@simtec.co.uk>
  *
  * Additional work by Herbert Pötzl <herbert@13thfloor.at> and
  * Harald Welte <laforge@openmoko.org>
  */

 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/gpio.h>
 #include <linux/input.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/io.h>

 #include <plat/adc.h>
 #include <plat/regs-adc.h>
 #include <linux/platform_data/touchscreen-s3c2410.h>

 #define TSC_SLEEP  (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0))

 #define INT_DOWN	(0)
 #define INT_UP		(1 << 8)

 #define WAIT4INT	(S3C2410_ADCTSC_YM_SEN | \
 			 S3C2410_ADCTSC_YP_SEN | \
 			 S3C2410_ADCTSC_XP_SEN | \
 			 S3C2410_ADCTSC_XY_PST(3))

 #define AUTOPST		(S3C2410_ADCTSC_YM_SEN | \
 			 S3C2410_ADCTSC_YP_SEN | \
 			 S3C2410_ADCTSC_XP_SEN | \
 			 S3C2410_ADCTSC_AUTO_PST | \
 			 S3C2410_ADCTSC_XY_PST(0))

 #define FEAT_PEN_IRQ	(1 << 0)	/* HAS ADCCLRINTPNDNUP */

 /* Per-touchscreen data. */

 /**
  * struct s3c2410ts - driver touchscreen state.
  * @client: The ADC client we registered with the core driver.
  * @dev: The device we are bound to.
  * @input: The input device we registered with the input subsystem.
  * @clock: The clock for the adc.
  * @io: Pointer to the IO base.
  * @xp: The accumulated X position data.
  * @yp: The accumulated Y position data.
  * @irq_tc: The interrupt number for pen up/down interrupt
  * @count: The number of samples collected.
  * @shift: The log2 of the maximum count to read in one go.
  * @features: The features supported by the TSADC MOdule.
  */
 struct s3c2410ts {
 	struct s3c_adc_client *client;
 	struct device *dev;
 	struct input_dev *input;
 	struct clk *clock;
 	void __iomem *io;
 	unsigned long xp;
 	unsigned long yp;
 	int irq_tc;
 	int count;
 	int shift;
 	int features;
 };

 static struct s3c2410ts ts;

 /**
  * get_down - return the down state of the pen
  * @data0: The data read from ADCDAT0 register.
  * @data1: The data read from ADCDAT1 register.
  *
  * Return non-zero if both readings show that the pen is down.
  */
 static inline bool get_down(unsigned long data0, unsigned long data1)
 {
 	/* returns true if both data values show stylus down */
 	return (!(data0 & S3C2410_ADCDAT0_UPDOWN) &&
 		!(data1 & S3C2410_ADCDAT0_UPDOWN));
 }

 static void touch_timer_fire(unsigned long data)
 {
 	unsigned long data0;
 	unsigned long data1;
 	bool down;

 	data0 = readl(ts.io + S3C2410_ADCDAT0);
 	data1 = readl(ts.io + S3C2410_ADCDAT1);

 	down = get_down(data0, data1);

 	if (down) {
 		if (ts.count == (1 << ts.shift)) {
 			ts.xp >>= ts.shift;
 			ts.yp >>= ts.shift;

 			dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n",
 				__func__, ts.xp, ts.yp, ts.count);

 			input_report_abs(ts.input, ABS_X, ts.xp);
 			input_report_abs(ts.input, ABS_Y, ts.yp);

 			input_report_key(ts.input, BTN_TOUCH, 1);
 			input_sync(ts.input);

 			ts.xp = 0;
 			ts.yp = 0;
 			ts.count = 0;
 		}

 		s3c_adc_start(ts.client, 0, 1 << ts.shift);
 	} else {
 		ts.xp = 0;
 		ts.yp = 0;
 		ts.count = 0;

 		input_report_key(ts.input, BTN_TOUCH, 0);
 		input_sync(ts.input);

 		writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
 	}
 }

 static DEFINE_TIMER(touch_timer, touch_timer_fire, 0, 0);

 /**
  * stylus_irq - touchscreen stylus event interrupt
  * @irq: The interrupt number
  * @dev_id: The device ID.
  *
  * Called when the IRQ_TC is fired for a pen up or down event.
  */
 static irqreturn_t stylus_irq(int irq, void *dev_id)
 {
 	unsigned long data0;
 	unsigned long data1;
 	bool down;

 	data0 = readl(ts.io + S3C2410_ADCDAT0);
 	data1 = readl(ts.io + S3C2410_ADCDAT1);

 	down = get_down(data0, data1);

 	/* TODO we should never get an interrupt with down set while
 	 * the timer is running, but maybe we ought to verify that the
 	 * timer isn't running anyways. */

 	if (down)
 		s3c_adc_start(ts.client, 0, 1 << ts.shift);
 	else
 		dev_dbg(ts.dev, "%s: count=%d\n", __func__, ts.count);

 	if (ts.features & FEAT_PEN_IRQ) {
 		/* Clear pen down/up interrupt */
 		writel(0x0, ts.io + S3C64XX_ADCCLRINTPNDNUP);
 	}

 	return IRQ_HANDLED;
 }

 /**
  * s3c24xx_ts_conversion - ADC conversion callback
  * @client: The client that was registered with the ADC core.
  * @data0: The reading from ADCDAT0.
  * @data1: The reading from ADCDAT1.
  * @left: The number of samples left.
  *
  * Called when a conversion has finished.
  */
 static void s3c24xx_ts_conversion(struct s3c_adc_client *client,
 				  unsigned data0, unsigned data1,
 				  unsigned *left)
 {
 	dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1);

 	ts.xp += data0;
 	ts.yp += data1;

 	ts.count++;

 	/* From tests, it seems that it is unlikely to get a pen-up
 	 * event during the conversion process which means we can
 	 * ignore any pen-up events with less than the requisite
 	 * count done.
 	 *
 	 * In several thousand conversions, no pen-ups where detected
 	 * before count completed.
 	 */
 }

 /**
  * s3c24xx_ts_select - ADC selection callback.
  * @client: The client that was registered with the ADC core.
  * @select: The reason for select.
  *
  * Called when the ADC core selects (or deslects) us as a client.
  */
 static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select)
 {
 	if (select) {
 		writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST,
 		       ts.io + S3C2410_ADCTSC);
 	} else {
 		mod_timer(&touch_timer, jiffies+1);
 		writel(WAIT4INT | INT_UP, ts.io + S3C2410_ADCTSC);
 	}
 }

 /**
  * s3c2410ts_probe - device core probe entry point
  * @pdev: The device we are being bound to.
  *
  * Initialise, find and allocate any resources we need to run and then
  * register with the ADC and input systems.
  */
 static int s3c2410ts_probe(struct platform_device *pdev)
 {
 	struct s3c2410_ts_mach_info *info;
 	struct device *dev = &pdev->dev;
 	struct input_dev *input_dev;
 	struct resource *res;
 	int ret = -EINVAL;

 	/* Initialise input stuff */
 	memset(&ts, 0, sizeof(struct s3c2410ts));

 	ts.dev = dev;

 	info = dev_get_platdata(dev);
 	if (!info) {
 		dev_err(dev, "no platform data, cannot attach\n");
 		return -EINVAL;
 	}

 	dev_dbg(dev, "initialising touchscreen\n");

 	ts.clock = clk_get(dev, "adc");
 	if (IS_ERR(ts.clock)) {
 		dev_err(dev, "cannot get adc clock source\n");
 		return -ENOENT;
 	}

 	clk_prepare_enable(ts.clock);
 	dev_dbg(dev, "got and enabled clocks\n");

 	ts.irq_tc = ret = platform_get_irq(pdev, 0);
 	if (ret < 0) {
 		dev_err(dev, "no resource for interrupt\n");
 		goto err_clk;
 	}

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(dev, "no resource for registers\n");
 		ret = -ENOENT;
 		goto err_clk;
 	}

 	ts.io = ioremap(res->start, resource_size(res));
 	if (ts.io == NULL) {
 		dev_err(dev, "cannot map registers\n");
 		ret = -ENOMEM;
 		goto err_clk;
 	}

 	/* inititalise the gpio */
 	if (info->cfg_gpio)
 		info->cfg_gpio(to_platform_device(ts.dev));

 	ts.client = s3c_adc_register(pdev, s3c24xx_ts_select,
 				     s3c24xx_ts_conversion, 1);
 	if (IS_ERR(ts.client)) {
 		dev_err(dev, "failed to register adc client\n");
 		ret = PTR_ERR(ts.client);
 		goto err_iomap;
 	}

 	/* Initialise registers */
 	if ((info->delay & 0xffff) > 0)
 		writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);

 	writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);

 	input_dev = input_allocate_device();
 	if (!input_dev) {
 		dev_err(dev, "Unable to allocate the input device !!\n");
 		ret = -ENOMEM;
 		goto err_iomap;
 	}

 	ts.input = input_dev;
 	ts.input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 	ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 	input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0);
 	input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0);

 	ts.input->name = "S3C24XX TouchScreen";
 	ts.input->id.bustype = BUS_HOST;
 	ts.input->id.vendor = 0xDEAD;
 	ts.input->id.product = 0xBEEF;
 	ts.input->id.version = 0x0102;

 	ts.shift = info->oversampling_shift;
 	ts.features = platform_get_device_id(pdev)->driver_data;

 	ret = request_irq(ts.irq_tc, stylus_irq, 0,
 			  "s3c2410_ts_pen", ts.input);
 	if (ret) {
 		dev_err(dev, "cannot get TC interrupt\n");
 		goto err_inputdev;
 	}

 	dev_info(dev, "driver attached, registering input device\n");

 	/* All went ok, so register to the input system */
 	ret = input_register_device(ts.input);
 	if (ret < 0) {
 		dev_err(dev, "failed to register input device\n");
 		ret = -EIO;
 		goto err_tcirq;
 	}

 	return 0;

  err_tcirq:
 	free_irq(ts.irq_tc, ts.input);
  err_inputdev:
 	input_free_device(ts.input);
  err_iomap:
 	iounmap(ts.io);
  err_clk:
 	del_timer_sync(&touch_timer);
 	clk_put(ts.clock);
 	return ret;
 }

 /**
  * s3c2410ts_remove - device core removal entry point
  * @pdev: The device we are being removed from.
  *
  * Free up our state ready to be removed.
  */
 static int s3c2410ts_remove(struct platform_device *pdev)
 {
 	free_irq(ts.irq_tc, ts.input);
 	del_timer_sync(&touch_timer);

 	clk_disable_unprepare(ts.clock);
 	clk_put(ts.clock);

 	input_unregister_device(ts.input);
 	iounmap(ts.io);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int s3c2410ts_suspend(struct device *dev)
 {
 	writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC);
 	disable_irq(ts.irq_tc);
 	clk_disable(ts.clock);

 	return 0;
 }

 static int s3c2410ts_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct s3c2410_ts_mach_info *info = dev_get_platdata(&pdev->dev);

 	clk_enable(ts.clock);
 	enable_irq(ts.irq_tc);

 	/* Initialise registers */
 	if ((info->delay & 0xffff) > 0)
 		writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);

 	writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);

 	return 0;
 }

 static const struct dev_pm_ops s3c_ts_pmops = {
 	.suspend	= s3c2410ts_suspend,
 	.resume		= s3c2410ts_resume,
 };
 #endif

 static const struct platform_device_id s3cts_driver_ids[] = {
 	{ "s3c2410-ts", 0 },
 	{ "s3c2440-ts", 0 },
 	{ "s3c64xx-ts", FEAT_PEN_IRQ },
 	{ }
 };
 MODULE_DEVICE_TABLE(platform, s3cts_driver_ids);

 static struct platform_driver s3c_ts_driver = {
 	.driver         = {
 		.name   = "samsung-ts",
 #ifdef CONFIG_PM
 		.pm	= &s3c_ts_pmops,
 #endif
 	},
 	.id_table	= s3cts_driver_ids,
 	.probe		= s3c2410ts_probe,
 	.remove		= s3c2410ts_remove,
 };
 module_platform_driver(s3c_ts_driver);

 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, "
 	      "Ben Dooks <ben@simtec.co.uk>, "
 	      "Simtec Electronics <linux@simtec.co.uk>");
 MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Samsung S3C24XX touchscreen driver
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the term 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	* Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org>
	* Copyright 2008 Ben Dooks <ben-linux@fluff.org>
	* Copyright 2009 Simtec Electronics <linux@simtec.co.uk>
	*
	* Additional work by Herbert Pötzl <herbert@13thfloor.at> and
	* Harald Welte <laforge@openmoko.org>
	*/

	#include <linux/errno.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/gpio.h>
	#include <linux/input.h>
	#include <linux/delay.h>
	#include <linux/interrupt.h>
	#include <linux/platform_device.h>
	#include <linux/clk.h>
	#include <linux/io.h>

	#include <plat/adc.h>
	#include <plat/regs-adc.h>
	#include <linux/platform_data/touchscreen-s3c2410.h>

	#define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE \| S3C2410_ADCTSC_XY_PST(0))

	#define INT_DOWN (0)
	#define INT_UP (1 << 8)

	#define WAIT4INT (S3C2410_ADCTSC_YM_SEN \| \
	S3C2410_ADCTSC_YP_SEN \| \
	S3C2410_ADCTSC_XP_SEN \| \
	S3C2410_ADCTSC_XY_PST(3))

	#define AUTOPST (S3C2410_ADCTSC_YM_SEN \| \
	S3C2410_ADCTSC_YP_SEN \| \
	S3C2410_ADCTSC_XP_SEN \| \
	S3C2410_ADCTSC_AUTO_PST \| \
	S3C2410_ADCTSC_XY_PST(0))

	#define FEAT_PEN_IRQ (1 << 0) /* HAS ADCCLRINTPNDNUP */

	/* Per-touchscreen data. */

	/**
	* struct s3c2410ts - driver touchscreen state.
	* @client: The ADC client we registered with the core driver.
	* @dev: The device we are bound to.
	* @input: The input device we registered with the input subsystem.
	* @clock: The clock for the adc.
	* @io: Pointer to the IO base.
	* @xp: The accumulated X position data.
	* @yp: The accumulated Y position data.
	* @irq_tc: The interrupt number for pen up/down interrupt
	* @count: The number of samples collected.
	* @shift: The log2 of the maximum count to read in one go.
	* @features: The features supported by the TSADC MOdule.
	*/
	struct s3c2410ts {
	struct s3c_adc_client *client;
	struct device *dev;
	struct input_dev *input;
	struct clk *clock;
	void __iomem *io;
	unsigned long xp;
	unsigned long yp;
	int irq_tc;
	int count;
	int shift;
	int features;
	};

	static struct s3c2410ts ts;

	/**
	* get_down - return the down state of the pen
	* @data0: The data read from ADCDAT0 register.
	* @data1: The data read from ADCDAT1 register.
	*
	* Return non-zero if both readings show that the pen is down.
	*/
	static inline bool get_down(unsigned long data0, unsigned long data1)
	{
	/* returns true if both data values show stylus down */
	return (!(data0 & S3C2410_ADCDAT0_UPDOWN) &&
	!(data1 & S3C2410_ADCDAT0_UPDOWN));
	}

	static void touch_timer_fire(unsigned long data)
	{
	unsigned long data0;
	unsigned long data1;
	bool down;

	data0 = readl(ts.io + S3C2410_ADCDAT0);
	data1 = readl(ts.io + S3C2410_ADCDAT1);

	down = get_down(data0, data1);

	if (down) {
	if (ts.count == (1 << ts.shift)) {
	ts.xp >>= ts.shift;
	ts.yp >>= ts.shift;

	dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n",
	__func__, ts.xp, ts.yp, ts.count);

	input_report_abs(ts.input, ABS_X, ts.xp);
	input_report_abs(ts.input, ABS_Y, ts.yp);

	input_report_key(ts.input, BTN_TOUCH, 1);
	input_sync(ts.input);

	ts.xp = 0;
	ts.yp = 0;
	ts.count = 0;
	}

	s3c_adc_start(ts.client, 0, 1 << ts.shift);
	} else {
	ts.xp = 0;
	ts.yp = 0;
	ts.count = 0;

	input_report_key(ts.input, BTN_TOUCH, 0);
	input_sync(ts.input);

	writel(WAIT4INT \| INT_DOWN, ts.io + S3C2410_ADCTSC);
	}
	}

	static DEFINE_TIMER(touch_timer, touch_timer_fire, 0, 0);

	/**
	* stylus_irq - touchscreen stylus event interrupt
	* @irq: The interrupt number
	* @dev_id: The device ID.
	*
	* Called when the IRQ_TC is fired for a pen up or down event.
	*/
	static irqreturn_t stylus_irq(int irq, void *dev_id)
	{
	unsigned long data0;
	unsigned long data1;
	bool down;

	data0 = readl(ts.io + S3C2410_ADCDAT0);
	data1 = readl(ts.io + S3C2410_ADCDAT1);

	down = get_down(data0, data1);

	/* TODO we should never get an interrupt with down set while
	* the timer is running, but maybe we ought to verify that the
	* timer isn't running anyways. */

	if (down)
	s3c_adc_start(ts.client, 0, 1 << ts.shift);
	else
	dev_dbg(ts.dev, "%s: count=%d\n", __func__, ts.count);

	if (ts.features & FEAT_PEN_IRQ) {
	/* Clear pen down/up interrupt */
	writel(0x0, ts.io + S3C64XX_ADCCLRINTPNDNUP);
	}

	return IRQ_HANDLED;
	}

	/**
	* s3c24xx_ts_conversion - ADC conversion callback
	* @client: The client that was registered with the ADC core.
	* @data0: The reading from ADCDAT0.
	* @data1: The reading from ADCDAT1.
	* @left: The number of samples left.
	*
	* Called when a conversion has finished.
	*/
	static void s3c24xx_ts_conversion(struct s3c_adc_client *client,
	unsigned data0, unsigned data1,
	unsigned *left)
	{
	dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1);

	ts.xp += data0;
	ts.yp += data1;

	ts.count++;

	/* From tests, it seems that it is unlikely to get a pen-up
	* event during the conversion process which means we can
	* ignore any pen-up events with less than the requisite
	* count done.
	*
	* In several thousand conversions, no pen-ups where detected
	* before count completed.
	*/
	}

	/**
	* s3c24xx_ts_select - ADC selection callback.
	* @client: The client that was registered with the ADC core.
	* @select: The reason for select.
	*
	* Called when the ADC core selects (or deslects) us as a client.
	*/
	static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select)
	{
	if (select) {
	writel(S3C2410_ADCTSC_PULL_UP_DISABLE \| AUTOPST,
	ts.io + S3C2410_ADCTSC);
	} else {
	mod_timer(&touch_timer, jiffies+1);
	writel(WAIT4INT \| INT_UP, ts.io + S3C2410_ADCTSC);
	}
	}

	/**
	* s3c2410ts_probe - device core probe entry point
	* @pdev: The device we are being bound to.
	*
	* Initialise, find and allocate any resources we need to run and then
	* register with the ADC and input systems.
	*/
	static int s3c2410ts_probe(struct platform_device *pdev)
	{
	struct s3c2410_ts_mach_info *info;
	struct device *dev = &pdev->dev;
	struct input_dev *input_dev;
	struct resource *res;
	int ret = -EINVAL;

	/* Initialise input stuff */
	memset(&ts, 0, sizeof(struct s3c2410ts));

	ts.dev = dev;

	info = dev_get_platdata(dev);
	if (!info) {
	dev_err(dev, "no platform data, cannot attach\n");
	return -EINVAL;
	}

	dev_dbg(dev, "initialising touchscreen\n");

	ts.clock = clk_get(dev, "adc");
	if (IS_ERR(ts.clock)) {
	dev_err(dev, "cannot get adc clock source\n");
	return -ENOENT;
	}

	clk_prepare_enable(ts.clock);
	dev_dbg(dev, "got and enabled clocks\n");

	ts.irq_tc = ret = platform_get_irq(pdev, 0);
	if (ret < 0) {
	dev_err(dev, "no resource for interrupt\n");
	goto err_clk;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(dev, "no resource for registers\n");
	ret = -ENOENT;
	goto err_clk;
	}

	ts.io = ioremap(res->start, resource_size(res));
	if (ts.io == NULL) {
	dev_err(dev, "cannot map registers\n");
	ret = -ENOMEM;
	goto err_clk;
	}

	/* inititalise the gpio */
	if (info->cfg_gpio)
	info->cfg_gpio(to_platform_device(ts.dev));

	ts.client = s3c_adc_register(pdev, s3c24xx_ts_select,
	s3c24xx_ts_conversion, 1);
	if (IS_ERR(ts.client)) {
	dev_err(dev, "failed to register adc client\n");
	ret = PTR_ERR(ts.client);
	goto err_iomap;
	}

	/* Initialise registers */
	if ((info->delay & 0xffff) > 0)
	writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);

	writel(WAIT4INT \| INT_DOWN, ts.io + S3C2410_ADCTSC);

	input_dev = input_allocate_device();
	if (!input_dev) {
	dev_err(dev, "Unable to allocate the input device !!\n");
	ret = -ENOMEM;
	goto err_iomap;
	}

	ts.input = input_dev;
	ts.input->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
	ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
	input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0);
	input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0);

	ts.input->name = "S3C24XX TouchScreen";
	ts.input->id.bustype = BUS_HOST;
	ts.input->id.vendor = 0xDEAD;
	ts.input->id.product = 0xBEEF;
	ts.input->id.version = 0x0102;

	ts.shift = info->oversampling_shift;
	ts.features = platform_get_device_id(pdev)->driver_data;

	ret = request_irq(ts.irq_tc, stylus_irq, 0,
	"s3c2410_ts_pen", ts.input);
	if (ret) {
	dev_err(dev, "cannot get TC interrupt\n");
	goto err_inputdev;
	}

	dev_info(dev, "driver attached, registering input device\n");

	/* All went ok, so register to the input system */
	ret = input_register_device(ts.input);
	if (ret < 0) {
	dev_err(dev, "failed to register input device\n");
	ret = -EIO;
	goto err_tcirq;
	}

	return 0;

	err_tcirq:
	free_irq(ts.irq_tc, ts.input);
	err_inputdev:
	input_free_device(ts.input);
	err_iomap:
	iounmap(ts.io);
	err_clk:
	del_timer_sync(&touch_timer);
	clk_put(ts.clock);
	return ret;
	}

	/**
	* s3c2410ts_remove - device core removal entry point
	* @pdev: The device we are being removed from.
	*
	* Free up our state ready to be removed.
	*/
	static int s3c2410ts_remove(struct platform_device *pdev)
	{
	free_irq(ts.irq_tc, ts.input);
	del_timer_sync(&touch_timer);

	clk_disable_unprepare(ts.clock);
	clk_put(ts.clock);

	input_unregister_device(ts.input);
	iounmap(ts.io);

	return 0;
	}

	#ifdef CONFIG_PM
	static int s3c2410ts_suspend(struct device *dev)
	{
	writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC);
	disable_irq(ts.irq_tc);
	clk_disable(ts.clock);

	return 0;
	}

	static int s3c2410ts_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct s3c2410_ts_mach_info *info = dev_get_platdata(&pdev->dev);

	clk_enable(ts.clock);
	enable_irq(ts.irq_tc);

	/* Initialise registers */
	if ((info->delay & 0xffff) > 0)
	writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);

	writel(WAIT4INT \| INT_DOWN, ts.io + S3C2410_ADCTSC);

	return 0;
	}

	static const struct dev_pm_ops s3c_ts_pmops = {
	.suspend = s3c2410ts_suspend,
	.resume = s3c2410ts_resume,
	};
	#endif

	static const struct platform_device_id s3cts_driver_ids[] = {
	{ "s3c2410-ts", 0 },
	{ "s3c2440-ts", 0 },
	{ "s3c64xx-ts", FEAT_PEN_IRQ },
	{ }
	};
	MODULE_DEVICE_TABLE(platform, s3cts_driver_ids);

	static struct platform_driver s3c_ts_driver = {
	.driver = {
	.name = "samsung-ts",
	#ifdef CONFIG_PM
	.pm = &s3c_ts_pmops,
	#endif
	},
	.id_table = s3cts_driver_ids,
	.probe = s3c2410ts_probe,
	.remove = s3c2410ts_remove,
	};
	module_platform_driver(s3c_ts_driver);

	MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, "
	"Ben Dooks <ben@simtec.co.uk>, "
	"Simtec Electronics <linux@simtec.co.uk>");
	MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
	MODULE_LICENSE("GPL v2");