Input: introduce tsc2005 driver

Discussions:

http://www.mail-archive.com/linux-omap@vger.kernel.org/msg26748.html

Introduce a driver for the Texas Instruments TSC2005 touchscreen
controller (http://focus.ti.com/docs/prod/folders/print/tsc2005.html).

The patch is based on a driver by Lauri Leukkunen, with modifications
by David Brownell, Phil Carmody, Imre Deak, Hiroshi DOYU, Ari Kauppi,
Tony Lindgren, Jarkko Nikula, Eero Nurkkala and Roman Tereshonkov.
Signed-off-by: NLauri Leukkunen <lauri.leukkunen@nokia.com>
[aaro.koskinen@nokia.com: patch description, rebasing & cleanup]
Signed-off-by: NAaro Koskinen <aaro.koskinen@nokia.com>
[ext-srikar.1.bhavanarayana@nokia.com: various fixes]
Signed-off-by: NSrikar <ext-srikar.1.bhavanarayana@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/Kconfig

@@ -629,6 +629,17 @@ config TOUCHSCREEN_TOUCHIT213
 	  To compile this driver as a module, choose M here: the
 	  module will be called touchit213.
 
+config TOUCHSCREEN_TSC2005
+        tristate "TSC2005 based touchscreens"
+        depends on SPI_MASTER
+        help
+          Say Y here if you have a TSC2005 based touchscreen.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called tsc2005.
+
 config TOUCHSCREEN_TSC2007
 	tristate "TSC2007 based touchscreens"
 	depends on I2C

drivers/input/touchscreen/Makefile

@@ -44,6 +44,7 @@ obj-$(CONFIG_TOUCHSCREEN_TNETV107X)	+= tnetv107x-ts.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213)	+= touchit213.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT)	+= touchright.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN)	+= touchwin.o
+obj-$(CONFIG_TOUCHSCREEN_TSC2005)	+= tsc2005.o
 obj-$(CONFIG_TOUCHSCREEN_TSC2007)	+= tsc2007.o
 obj-$(CONFIG_TOUCHSCREEN_UCB1400)	+= ucb1400_ts.o
 obj-$(CONFIG_TOUCHSCREEN_WACOM_W8001)	+= wacom_w8001.o

drivers/input/touchscreen/tsc2005.c

+/*
+ * TSC2005 touchscreen driver
+ *
+ * Copyright (C) 2006-2010 Nokia Corporation
+ *
+ * Author: Lauri Leukkunen <lauri.leukkunen@nokia.com>
+ * based on TSC2301 driver by Klaus K. Pedersen <klaus.k.pedersen@nokia.com>
+ *
+ * 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.
+ *
+ * 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
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/tsc2005.h>
+
+/*
+ * The touchscreen interface operates as follows:
+ *
+ * 1) Pen is pressed against the touchscreen.
+ * 2) TSC2005 performs AD conversion.
+ * 3) After the conversion is done TSC2005 drives DAV line down.
+ * 4) GPIO IRQ is received and tsc2005_irq_thread() is scheduled.
+ * 5) tsc2005_irq_thread() queues up an spi transfer to fetch the x, y, z1, z2
+ *    values.
+ * 6) tsc2005_irq_thread() reports coordinates to input layer and sets up
+ *    tsc2005_penup_timer() to be called after TSC2005_PENUP_TIME_MS (40ms).
+ * 7) When the penup timer expires, there have not been touch or DAV interrupts
+ *    during the last 40ms which means the pen has been lifted.
+ *
+ * ESD recovery via a hardware reset is done if the TSC2005 doesn't respond
+ * after a configurable period (in ms) of activity. If esd_timeout is 0, the
+ * watchdog is disabled.
+ */
+
+/* control byte 1 */
+#define TSC2005_CMD			0x80
+#define TSC2005_CMD_NORMAL		0x00
+#define TSC2005_CMD_STOP		0x01
+#define TSC2005_CMD_12BIT		0x04
+
+/* control byte 0 */
+#define TSC2005_REG_READ		0x0001
+#define TSC2005_REG_PND0		0x0002
+#define TSC2005_REG_X			0x0000
+#define TSC2005_REG_Y			0x0008
+#define TSC2005_REG_Z1			0x0010
+#define TSC2005_REG_Z2			0x0018
+#define TSC2005_REG_TEMP_HIGH		0x0050
+#define TSC2005_REG_CFR0		0x0060
+#define TSC2005_REG_CFR1		0x0068
+#define TSC2005_REG_CFR2		0x0070
+
+/* configuration register 0 */
+#define TSC2005_CFR0_PRECHARGE_276US	0x0040
+#define TSC2005_CFR0_STABTIME_1MS	0x0300
+#define TSC2005_CFR0_CLOCK_1MHZ		0x1000
+#define TSC2005_CFR0_RESOLUTION12	0x2000
+#define TSC2005_CFR0_PENMODE		0x8000
+#define TSC2005_CFR0_INITVALUE		(TSC2005_CFR0_STABTIME_1MS    | \
+					 TSC2005_CFR0_CLOCK_1MHZ      | \
+					 TSC2005_CFR0_RESOLUTION12    | \
+					 TSC2005_CFR0_PRECHARGE_276US | \
+					 TSC2005_CFR0_PENMODE)
+
+/* bits common to both read and write of configuration register 0 */
+#define	TSC2005_CFR0_RW_MASK		0x3fff
+
+/* configuration register 1 */
+#define TSC2005_CFR1_BATCHDELAY_4MS	0x0003
+#define TSC2005_CFR1_INITVALUE		TSC2005_CFR1_BATCHDELAY_4MS
+
+/* configuration register 2 */
+#define TSC2005_CFR2_MAVE_Z		0x0004
+#define TSC2005_CFR2_MAVE_Y		0x0008
+#define TSC2005_CFR2_MAVE_X		0x0010
+#define TSC2005_CFR2_AVG_7		0x0800
+#define TSC2005_CFR2_MEDIUM_15		0x3000
+#define TSC2005_CFR2_INITVALUE		(TSC2005_CFR2_MAVE_X	| \
+					 TSC2005_CFR2_MAVE_Y	| \
+					 TSC2005_CFR2_MAVE_Z	| \
+					 TSC2005_CFR2_MEDIUM_15	| \
+					 TSC2005_CFR2_AVG_7)
+
+#define MAX_12BIT			0xfff
+#define TSC2005_SPI_MAX_SPEED_HZ	10000000
+#define TSC2005_PENUP_TIME_MS		40
+
+struct tsc2005_spi_rd {
+	struct spi_transfer	spi_xfer;
+	u32			spi_tx;
+	u32			spi_rx;
+};
+
+struct tsc2005 {
+	struct spi_device	*spi;
+
+	struct spi_message      spi_read_msg;
+	struct tsc2005_spi_rd	spi_x;
+	struct tsc2005_spi_rd	spi_y;
+	struct tsc2005_spi_rd	spi_z1;
+	struct tsc2005_spi_rd	spi_z2;
+
+	struct input_dev	*idev;
+	char			phys[32];
+
+	struct mutex		mutex;
+
+	/* raw copy of previous x,y,z */
+	int			in_x;
+	int			in_y;
+	int                     in_z1;
+	int			in_z2;
+
+	struct timer_list	penup_timer;
+	struct work_struct	penup_work;
+
+	unsigned int		esd_timeout;
+	struct timer_list	esd_timer;
+	struct work_struct	esd_work;
+
+	unsigned int		x_plate_ohm;
+
+	bool			disabled;
+	unsigned int		disable_depth;
+	unsigned int		pen_down;
+
+	void			(*set_reset)(bool enable);
+};
+
+static void tsc2005_cmd(struct tsc2005 *ts, u8 cmd)
+{
+	u8 tx;
+	struct spi_message msg;
+	struct spi_transfer xfer = { 0 };
+
+	tx = TSC2005_CMD | TSC2005_CMD_12BIT | cmd;
+
+	xfer.tx_buf = &tx;
+	xfer.rx_buf = NULL;
+	xfer.len = 1;
+	xfer.bits_per_word = 8;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+	spi_sync(ts->spi, &msg);
+}
+
+static void tsc2005_write(struct tsc2005 *ts, u8 reg, u16 value)
+{
+	u32 tx;
+	struct spi_message msg;
+	struct spi_transfer xfer = { 0 };
+
+	tx = (reg | TSC2005_REG_PND0) << 16;
+	tx |= value;
+
+	xfer.tx_buf = &tx;
+	xfer.rx_buf = NULL;
+	xfer.len = 4;
+	xfer.bits_per_word = 24;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+	spi_sync(ts->spi, &msg);
+}
+
+static void tsc2005_setup_read(struct tsc2005_spi_rd *rd, u8 reg, bool last)
+{
+	rd->spi_tx		   = (reg | TSC2005_REG_READ) << 16;
+	rd->spi_xfer.tx_buf	   = &rd->spi_tx;
+	rd->spi_xfer.rx_buf	   = &rd->spi_rx;
+	rd->spi_xfer.len	   = 4;
+	rd->spi_xfer.bits_per_word = 24;
+	rd->spi_xfer.cs_change	   = !last;
+}
+
+static void tsc2005_read(struct tsc2005 *ts, u8 reg, u16 *value)
+{
+	struct spi_message msg;
+	struct tsc2005_spi_rd spi_rd = { { 0 }, 0, 0 };
+
+	tsc2005_setup_read(&spi_rd, reg, 1);
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&spi_rd.spi_xfer, &msg);
+	spi_sync(ts->spi, &msg);
+	*value = spi_rd.spi_rx;
+}
+
+static void tsc2005_update_pen_state(struct tsc2005 *ts,
+				     int x, int y, int pressure)
+{
+	if (pressure) {
+		input_report_abs(ts->idev, ABS_X, x);
+		input_report_abs(ts->idev, ABS_Y, y);
+		input_report_abs(ts->idev, ABS_PRESSURE, pressure);
+		if (!ts->pen_down) {
+			input_report_key(ts->idev, BTN_TOUCH, !!pressure);
+			ts->pen_down = 1;
+		}
+	} else {
+		input_report_abs(ts->idev, ABS_PRESSURE, 0);
+		if (ts->pen_down) {
+			input_report_key(ts->idev, BTN_TOUCH, 0);
+			ts->pen_down = 0;
+		}
+	}
+	input_sync(ts->idev);
+	dev_dbg(&ts->spi->dev, "point(%4d,%4d), pressure (%4d)\n", x, y,
+		pressure);
+}
+
+static irqreturn_t tsc2005_irq_handler(int irq, void *dev_id)
+{
+	struct tsc2005 *ts = dev_id;
+
+	/* update the penup timer only if it's pending */
+	mod_timer_pending(&ts->penup_timer,
+			  jiffies + msecs_to_jiffies(TSC2005_PENUP_TIME_MS));
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t tsc2005_irq_thread(int irq, void *_ts)
+{
+	struct tsc2005 *ts = _ts;
+	unsigned int pressure;
+	u32 x;
+	u32 y;
+	u32 z1;
+	u32 z2;
+
+	mutex_lock(&ts->mutex);
+
+	if (unlikely(ts->disable_depth))
+		goto out;
+
+	/* read the coordinates */
+	spi_sync(ts->spi, &ts->spi_read_msg);
+	x = ts->spi_x.spi_rx;
+	y = ts->spi_y.spi_rx;
+	z1 = ts->spi_z1.spi_rx;
+	z2 = ts->spi_z2.spi_rx;
+
+	/* validate position */
+	if (unlikely(x > MAX_12BIT || y > MAX_12BIT))
+		goto out;
+
+	/* skip coords if the pressure components are out of range */
+	if (unlikely(z1 == 0 || z2 > MAX_12BIT || z1 >= z2))
+		goto out;
+
+       /* skip point if this is a pen down with the exact same values as
+	* the value before pen-up - that implies SPI fed us stale data
+	*/
+	if (!ts->pen_down &&
+	ts->in_x == x &&
+	ts->in_y == y &&
+	ts->in_z1 == z1 &&
+	ts->in_z2 == z2)
+		goto out;
+
+	/* At this point we are happy we have a valid and useful reading.
+	* Remember it for later comparisons. We may now begin downsampling
+	*/
+	ts->in_x = x;
+	ts->in_y = y;
+	ts->in_z1 = z1;
+	ts->in_z2 = z2;
+
+	/* compute touch pressure resistance using equation #1 */
+	pressure = x * (z2 - z1) / z1;
+	pressure = pressure * ts->x_plate_ohm / 4096;
+	if (unlikely(pressure > MAX_12BIT))
+		goto out;
+
+	tsc2005_update_pen_state(ts, x, y, pressure);
+
+	/* set the penup timer */
+	mod_timer(&ts->penup_timer,
+		  jiffies + msecs_to_jiffies(TSC2005_PENUP_TIME_MS));
+
+	if (!ts->esd_timeout)
+		goto out;
+
+	/* update the watchdog timer */
+	mod_timer(&ts->esd_timer,
+		  round_jiffies(jiffies + msecs_to_jiffies(ts->esd_timeout)));
+
+out:
+	mutex_unlock(&ts->mutex);
+	return IRQ_HANDLED;
+}
+
+static void tsc2005_penup_timer(unsigned long data)
+{
+	struct tsc2005 *ts = (struct tsc2005 *)data;
+
+	schedule_work(&ts->penup_work);
+}
+
+static void tsc2005_penup_work(struct work_struct *work)
+{
+	struct tsc2005 *ts = container_of(work, struct tsc2005, penup_work);
+
+	mutex_lock(&ts->mutex);
+	tsc2005_update_pen_state(ts, 0, 0, 0);
+	mutex_unlock(&ts->mutex);
+}
+
+static void tsc2005_start_scan(struct tsc2005 *ts)
+{
+	tsc2005_write(ts, TSC2005_REG_CFR0, TSC2005_CFR0_INITVALUE);
+	tsc2005_write(ts, TSC2005_REG_CFR1, TSC2005_CFR1_INITVALUE);
+	tsc2005_write(ts, TSC2005_REG_CFR2, TSC2005_CFR2_INITVALUE);
+	tsc2005_cmd(ts, TSC2005_CMD_NORMAL);
+}
+
+static void tsc2005_stop_scan(struct tsc2005 *ts)
+{
+	tsc2005_cmd(ts, TSC2005_CMD_STOP);
+}
+
+/* must be called with mutex held */
+static void tsc2005_disable(struct tsc2005 *ts)
+{
+	if (ts->disable_depth++ != 0)
+		return;
+	disable_irq(ts->spi->irq);
+	if (ts->esd_timeout)
+		del_timer_sync(&ts->esd_timer);
+	del_timer_sync(&ts->penup_timer);
+	tsc2005_stop_scan(ts);
+}
+
+/* must be called with mutex held */
+static void tsc2005_enable(struct tsc2005 *ts)
+{
+	if (--ts->disable_depth != 0)
+		return;
+	tsc2005_start_scan(ts);
+	enable_irq(ts->spi->irq);
+	if (!ts->esd_timeout)
+		return;
+	mod_timer(&ts->esd_timer,
+		  round_jiffies(jiffies + msecs_to_jiffies(ts->esd_timeout)));
+}
+
+static ssize_t tsc2005_disable_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct tsc2005 *ts = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", ts->disabled);
+}
+
+static ssize_t tsc2005_disable_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct tsc2005 *ts = dev_get_drvdata(dev);
+	unsigned long res;
+	int i;
+
+	if (strict_strtoul(buf, 10, &res) < 0)
+		return -EINVAL;
+	i = res ? 1 : 0;
+
+	mutex_lock(&ts->mutex);
+	if (i == ts->disabled)
+		goto out;
+	ts->disabled = i;
+	if (i)
+		tsc2005_disable(ts);
+	else
+		tsc2005_enable(ts);
+out:
+	mutex_unlock(&ts->mutex);
+	return count;
+}
+static DEVICE_ATTR(disable, 0664, tsc2005_disable_show, tsc2005_disable_store);
+
+static ssize_t tsc2005_selftest_show(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct tsc2005 *ts = dev_get_drvdata(dev);
+	u16 temp_high;
+	u16 temp_high_orig;
+	u16 temp_high_test;
+	unsigned int result;
+
+	if (!ts->set_reset) {
+		dev_warn(&ts->spi->dev,
+			 "unable to selftest: no reset function\n");
+		result = 0;
+		goto out;
+	}
+
+	mutex_lock(&ts->mutex);
+
+	/*
+	 * Test TSC2005 communications via temp high register.
+	 */
+	tsc2005_disable(ts);
+	result = 1;
+	tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high_orig);
+	temp_high_test = (temp_high_orig - 1) & MAX_12BIT;
+	tsc2005_write(ts, TSC2005_REG_TEMP_HIGH, temp_high_test);
+	tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);
+	if (temp_high != temp_high_test) {
+		dev_warn(dev, "selftest failed: %d != %d\n",
+			 temp_high, temp_high_test);
+		result = 0;
+	}
+
+	/* hardware reset */
+	ts->set_reset(0);
+	usleep_range(100, 500); /* only 10us required */
+	ts->set_reset(1);
+	tsc2005_enable(ts);
+
+	/* test that the reset really happened */
+	tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);
+	if (temp_high != temp_high_orig) {
+		dev_warn(dev, "selftest failed after reset: %d != %d\n",
+			 temp_high, temp_high_orig);
+		result = 0;
+	}
+
+	mutex_unlock(&ts->mutex);
+
+out:
+	return sprintf(buf, "%u\n", result);
+}
+static DEVICE_ATTR(selftest, S_IRUGO, tsc2005_selftest_show, NULL);
+
+static void tsc2005_esd_timer(unsigned long data)
+{
+	struct tsc2005 *ts = (struct tsc2005 *)data;
+
+	schedule_work(&ts->esd_work);
+}
+
+static void tsc2005_esd_work(struct work_struct *work)
+{
+	struct tsc2005 *ts = container_of(work, struct tsc2005, esd_work);
+	u16 r;
+
+	mutex_lock(&ts->mutex);
+
+	if (ts->disable_depth)
+		goto out;
+
+	/*
+	 * If we cannot read our known value from configuration register 0 then
+	 * reset the controller as if from power-up and start scanning again.
+	 */
+	tsc2005_read(ts, TSC2005_REG_CFR0, &r);
+	if ((r ^ TSC2005_CFR0_INITVALUE) & TSC2005_CFR0_RW_MASK) {
+		dev_info(&ts->spi->dev, "TSC2005 not responding - resetting\n");
+		ts->set_reset(0);
+		tsc2005_update_pen_state(ts, 0, 0, 0);
+		usleep_range(100, 500); /* only 10us required */
+		ts->set_reset(1);
+		tsc2005_start_scan(ts);
+	}
+
+	/* re-arm the watchdog */
+	mod_timer(&ts->esd_timer,
+		  round_jiffies(jiffies + msecs_to_jiffies(ts->esd_timeout)));
+
+out:
+	mutex_unlock(&ts->mutex);
+}
+
+static void __devinit tsc2005_setup_spi_xfer(struct tsc2005 *ts)
+{
+	tsc2005_setup_read(&ts->spi_x, TSC2005_REG_X, 0);
+	tsc2005_setup_read(&ts->spi_y, TSC2005_REG_Y, 0);
+	tsc2005_setup_read(&ts->spi_z1, TSC2005_REG_Z1, 0);
+	tsc2005_setup_read(&ts->spi_z2, TSC2005_REG_Z2, 1);
+
+	spi_message_init(&ts->spi_read_msg);
+	spi_message_add_tail(&ts->spi_x.spi_xfer, &ts->spi_read_msg);
+	spi_message_add_tail(&ts->spi_y.spi_xfer, &ts->spi_read_msg);
+	spi_message_add_tail(&ts->spi_z1.spi_xfer, &ts->spi_read_msg);
+	spi_message_add_tail(&ts->spi_z2.spi_xfer, &ts->spi_read_msg);
+}
+
+static struct attribute *tsc2005_attrs[] = {
+	&dev_attr_disable.attr,
+	&dev_attr_selftest.attr,
+	NULL
+};
+
+static struct attribute_group tsc2005_attr_group = {
+	.attrs = tsc2005_attrs,
+};
+
+static int __devinit tsc2005_setup(struct tsc2005 *ts,
+				   struct tsc2005_platform_data *pdata)
+{
+	int r;
+	int fudge_x;
+	int fudge_y;
+	int fudge_p;
+	int p_max;
+	int x_max;
+	int y_max;
+
+	mutex_init(&ts->mutex);
+
+	tsc2005_setup_spi_xfer(ts);
+
+	init_timer(&ts->penup_timer);
+	setup_timer(&ts->penup_timer, tsc2005_penup_timer, (unsigned long)ts);
+	INIT_WORK(&ts->penup_work, tsc2005_penup_work);
+
+	fudge_x		= pdata->ts_x_fudge	   ? : 4;
+	fudge_y		= pdata->ts_y_fudge	   ? : 8;
+	fudge_p		= pdata->ts_pressure_fudge ? : 2;
+	x_max		= pdata->ts_x_max	   ? : MAX_12BIT;
+	y_max		= pdata->ts_y_max	   ? : MAX_12BIT;
+	p_max		= pdata->ts_pressure_max   ? : MAX_12BIT;
+	ts->x_plate_ohm	= pdata->ts_x_plate_ohm	   ? : 280;
+	ts->esd_timeout	= pdata->esd_timeout_ms;
+	ts->set_reset	= pdata->set_reset;
+
+	ts->idev = input_allocate_device();
+	if (ts->idev == NULL)
+		return -ENOMEM;
+	ts->idev->name = "TSC2005 touchscreen";
+	snprintf(ts->phys, sizeof(ts->phys), "%s/input-ts",
+		 dev_name(&ts->spi->dev));
+	ts->idev->phys = ts->phys;
+	ts->idev->evbit[0] = BIT(EV_ABS) | BIT(EV_KEY);
+	ts->idev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE);
+	ts->idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+	input_set_abs_params(ts->idev, ABS_X, 0, x_max, fudge_x, 0);
+	input_set_abs_params(ts->idev, ABS_Y, 0, y_max, fudge_y, 0);
+	input_set_abs_params(ts->idev, ABS_PRESSURE, 0, p_max, fudge_p, 0);
+
+	r = request_threaded_irq(ts->spi->irq, tsc2005_irq_handler,
+				 tsc2005_irq_thread, IRQF_TRIGGER_RISING,
+				 "tsc2005", ts);
+	if (r) {
+		dev_err(&ts->spi->dev, "request_threaded_irq(): %d\n", r);
+		goto err1;
+	}
+	set_irq_wake(ts->spi->irq, 1);
+
+	r = input_register_device(ts->idev);
+	if (r) {
+		dev_err(&ts->spi->dev, "input_register_device(): %d\n", r);
+		goto err2;
+	}
+
+	r = sysfs_create_group(&ts->spi->dev.kobj, &tsc2005_attr_group);
+	if (r)
+		dev_warn(&ts->spi->dev, "sysfs entry creation failed: %d\n", r);
+
+	tsc2005_start_scan(ts);
+
+	if (!ts->esd_timeout || !ts->set_reset)
+		goto done;
+
+	/* start the optional ESD watchdog */
+	setup_timer(&ts->esd_timer, tsc2005_esd_timer, (unsigned long)ts);
+	INIT_WORK(&ts->esd_work, tsc2005_esd_work);
+	mod_timer(&ts->esd_timer,
+		  round_jiffies(jiffies + msecs_to_jiffies(ts->esd_timeout)));
+
+done:
+	return 0;
+
+err2:
+	free_irq(ts->spi->irq, ts);
+
+err1:
+	input_free_device(ts->idev);
+	return r;
+}
+
+static int __devinit tsc2005_probe(struct spi_device *spi)
+{
+	struct tsc2005_platform_data *pdata = spi->dev.platform_data;
+	struct tsc2005 *ts;
+	int r;
+
+	if (spi->irq < 0) {
+		dev_dbg(&spi->dev, "no irq\n");
+		return -ENODEV;
+	}
+
+	if (!pdata) {
+		dev_dbg(&spi->dev, "no platform data\n");
+		return -ENODEV;
+	}
+
+	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+	if (ts == NULL)
+		return -ENOMEM;
+
+	dev_set_drvdata(&spi->dev, ts);
+	ts->spi = spi;
+	spi->dev.power.power_state = PMSG_ON;
+	spi->mode = SPI_MODE_0;
+	spi->bits_per_word = 8;
+	if (!spi->max_speed_hz)
+		spi->max_speed_hz = TSC2005_SPI_MAX_SPEED_HZ;
+	spi_setup(spi);
+
+	r = tsc2005_setup(ts, pdata);
+	if (r)
+		kfree(ts);
+	return r;
+}
+
+static int __devexit tsc2005_remove(struct spi_device *spi)
+{
+	struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
+
+	mutex_lock(&ts->mutex);
+	tsc2005_disable(ts);
+	mutex_unlock(&ts->mutex);
+
+	if (ts->esd_timeout)
+		del_timer_sync(&ts->esd_timer);
+	del_timer_sync(&ts->penup_timer);
+
+	flush_work(&ts->esd_work);
+	flush_work(&ts->penup_work);
+
+	sysfs_remove_group(&ts->spi->dev.kobj, &tsc2005_attr_group);
+	free_irq(ts->spi->irq, ts);
+	input_unregister_device(ts->idev);
+	kfree(ts);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int tsc2005_suspend(struct spi_device *spi, pm_message_t mesg)
+{
+	struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
+
+	mutex_lock(&ts->mutex);
+	tsc2005_disable(ts);
+	mutex_unlock(&ts->mutex);
+
+	return 0;
+}
+
+static int tsc2005_resume(struct spi_device *spi)
+{
+	struct tsc2005 *ts = dev_get_drvdata(&spi->dev);
+
+	mutex_lock(&ts->mutex);
+	tsc2005_enable(ts);
+	mutex_unlock(&ts->mutex);
+
+	return 0;
+}
+#endif
+
+static struct spi_driver tsc2005_driver = {
+	.driver = {
+		.name = "tsc2005",
+		.owner = THIS_MODULE,
+	},
+#ifdef CONFIG_PM
+	.suspend = tsc2005_suspend,
+	.resume = tsc2005_resume,
+#endif
+	.probe = tsc2005_probe,
+	.remove = __devexit_p(tsc2005_remove),
+};
+
+static int __init tsc2005_init(void)
+{
+	printk(KERN_INFO "TSC2005 driver initializing\n");
+	return spi_register_driver(&tsc2005_driver);
+}
+module_init(tsc2005_init);
+
+static void __exit tsc2005_exit(void)
+{
+	spi_unregister_driver(&tsc2005_driver);
+}
+module_exit(tsc2005_exit);
+
+MODULE_AUTHOR("Lauri Leukkunen <lauri.leukkunen@nokia.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:tsc2005");

include/linux/spi/tsc2005.h

+/*
+ * This file is part of TSC2005 touchscreen driver
+ *
+ * Copyright (C) 2009-2010 Nokia Corporation
+ *
+ * Contact: Aaro Koskinen <aaro.koskinen@nokia.com>
+ *
+ * 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.
+ *
+ * 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
+ *
+ */
+
+#ifndef _LINUX_SPI_TSC2005_H
+#define _LINUX_SPI_TSC2005_H
+
+#include <linux/types.h>
+
+struct tsc2005_platform_data {
+	int		ts_pressure_max;
+	int		ts_pressure_fudge;
+	int		ts_x_max;
+	int		ts_x_fudge;
+	int		ts_y_max;
+	int		ts_y_fudge;
+	int		ts_x_plate_ohm;
+	unsigned int	esd_timeout_ms;
+	void		(*set_reset)(bool enable);
+};
+
+#endif