Staging: add Synaptics TM1217 Touchscreen Controller driver

This is submitted as a staging driver because there is a more generic driver
"on the way" for all these devices and has been for some time. The intent is
that as soon as the general drivers are in the mainstream this one will get
any leftovers integrated and then be dumped. Until this unspecified future
data at least people can actually use their hardware.

As its interface is simply input layer we can do that without pain.

Some clean up by Alan Cox
  - Extract gpio support and IRQ support more sanely
  - Tidying

Signed-off-by: Ramesh Agarwal <ramesh.agarwal@intel.com>
[avoid deference NULL ts if kzalloc fails]
[finger_touched may be used uninitialized]
[fix missing sync which confused twm]
Signed-off-by: Hong Liu <hong.liu@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/Kconfig

@@ -175,5 +175,7 @@ source "drivers/staging/intel_sst/Kconfig"
 
 source "drivers/staging/speakup/Kconfig"
 
+source "drivers/staging/cptm1217/Kconfig"
+
 endif # !STAGING_EXCLUDE_BUILD
 endif # STAGING

drivers/staging/Makefile

@@ -68,3 +68,4 @@ obj-$(CONFIG_BCM_WIMAX)	+= bcm/
 obj-$(CONFIG_FT1000)		+= ft1000/
 obj-$(CONFIG_SND_INTEL_SST)		+= intel_sst/
 obj-$(CONFIG_SPEAKUP)	+= speakup/
+obj-$(CONFIG_TOUCHSCREEN_CLEARPAD_TM1217)	+= cptm1217/

drivers/staging/cptm1217/Kconfig

@@ -0,0 +1,11 @@
+config TOUCHSCREEN_CLEARPAD_TM1217
+	tristate "Synaptics Clearpad TM1217"
+	depends on I2C
+	depends on GPIOLIB
+	help
+	  Say Y here if you have a Synaptics Clearpad TM1217 Controller
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called clearpad_tm1217.

drivers/staging/cptm1217/Makefile

@@ -0,0 +1,2 @@
+obj-$(CONFIG_TOUCHSCREEN_CLEARPAD_TM1217)	+= clearpad_tm1217.o
+

drivers/staging/cptm1217/TODO

@@ -0,0 +1,5 @@
+- Wait for the official upstream general clearpad drivers as promised over
+  the past few months
+- Merge any device support needed from this driver into it
+- Delete this driver
+

drivers/staging/cptm1217/clearpad_tm1217.c

@@ -0,0 +1,675 @@
+/*
+ * clearpad_tm1217.c - Touch Screen driver for Synaptics Clearpad
+ * TM1217 controller
+ *
+ * Copyright (C) 2008 Intel Corp
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * 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; version 2 of the License.
+ *
+ * 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; ifnot, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Questions/Comments/Bug fixes to Ramesh Agarwal (ramesh.agarwal@intel.com)
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+#include <linux/gpio.h>
+#include <linux/hrtimer.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include "cp_tm1217.h"
+
+#define CPTM1217_DEVICE_NAME		"cptm1217"
+#define CPTM1217_DRIVER_NAME		CPTM1217_DEVICE_NAME
+
+#define MAX_TOUCH_SUPPORTED		2
+#define TOUCH_SUPPORTED			1
+#define SAMPLING_FREQ			80	/* Frequency in HZ */
+#define DELAY_BTWIN_SAMPLE		(1000 / SAMPLING_FREQ)
+#define WAIT_FOR_RESPONSE		5	/* 5msec just works */
+#define MAX_RETRIES			5	/* As above */
+#define INCREMENTAL_DELAY		5	/* As above */
+
+/* Regster Definitions */
+#define TMA1217_DEV_STATUS		0x13	/* Device Status */
+#define TMA1217_INT_STATUS		0x14	/* Interrupt Status */
+
+/* Controller can detect upto 2 possible finger touches.
+ * Each finger touch provides  12 bit X Y co-ordinates, the values are split
+ * across 2 registers, and an 8 bit  Z value */
+#define TMA1217_FINGER_STATE		0x18 /* Finger State */
+#define TMA1217_FINGER1_X_HIGHER8	0x19 /* Higher 8 bit of X coordinate */
+#define TMA1217_FINGER1_Y_HIGHER8	0x1A /* Higher 8 bit of Y coordinate */
+#define TMA1217_FINGER1_XY_LOWER4	0x1B /* Lower 4 bits of X and Y */
+#define TMA1217_FINGER1_Z_VALUE		0x1D /* 8 bit Z value for finger 1 */
+#define TMA1217_FINGER2_X_HIGHER8	0x1E /* Higher 8 bit of X coordinate */
+#define TMA1217_FINGER2_Y_HIGHER8	0x1F /* Higher 8 bit of Y coordinate */
+#define TMA1217_FINGER2_XY_LOWER4	0x20 /* Lower 4 bits of X and Y */
+#define TMA1217_FINGER2_Z_VALUE		0x22 /* 8 bit Z value for finger 2 */
+#define TMA1217_DEVICE_CTRL		0x23 /* Device Control */
+#define TMA1217_INTERRUPT_ENABLE	0x24 /* Interrupt Enable */
+#define TMA1217_REPORT_MODE		0x2B /* Reporting Mode */
+#define TMA1217_MAX_X_LOWER8		0x31 /* Bit 0-7 for Max X */
+#define TMA1217_MAX_X_HIGHER4		0x32 /* Bit 8-11 for Max X */
+#define TMA1217_MAX_Y_LOWER8		0x33 /* Bit 0-7 for Max Y */
+#define TMA1217_MAX_Y_HIGHER4		0x34 /* Bit 8-11 for Max Y */
+#define TMA1217_DEVICE_CMD_RESET	0x67 /* Device CMD reg for reset */
+#define TMA1217_DEVICE_CMD_REZERO	0x69 /* Device CMD reg for rezero */
+
+#define TMA1217_MANUFACTURER_ID		0x73 /* Manufacturer Id */
+#define TMA1217_PRODUCT_FAMILY		0x75 /* Product Family */
+#define TMA1217_FIRMWARE_REVISION	0x76 /* Firmware Revision */
+#define TMA1217_SERIAL_NO_HIGH		0x7C /* Bit 8-15 of device serial no. */
+#define TMA1217_SERIAL_NO_LOW		0x7D /* Bit 0-7 of device serial no. */
+#define TMA1217_PRODUCT_ID_START	0x7E /* Start address for 10 byte ID */
+#define TMA1217_DEVICE_CAPABILITY	0x8B /* Reporting capability */
+
+
+/*
+ * The touch position structure.
+ */
+struct touch_state {
+	int	x;
+	int	y;
+	bool button;
+};
+
+/* Device Specific info given by the controller */
+struct cp_dev_info {
+	u16	maxX;
+	u16	maxY;
+};
+
+/* Vendor related info given by the controller */
+struct cp_vendor_info {
+	u8	vendor_id;
+	u8	product_family;
+	u8	firmware_rev;
+	u16	serial_no;
+};
+
+/*
+ * Private structure to store the device details
+ */
+struct cp_tm1217_device {
+	struct i2c_client	*client;
+	struct device		*dev;
+	struct cp_vendor_info	vinfo;
+	struct cp_dev_info	dinfo;
+	struct input_dev_info {
+		char			phys[32];
+		char			name[128];
+		struct input_dev	*input;
+		struct touch_state	touch;
+	} cp_input_info[MAX_TOUCH_SUPPORTED];
+
+	int	thread_running;
+	struct mutex	thread_mutex;
+
+	int gpio;
+};
+
+
+/* The following functions are used to read/write registers on the device
+ * as per the RMI prorocol. Technically, a page select should be written
+ * before doing read/write but since the register offsets are below 0xFF
+ * we can use the default value of page which is 0x00
+ */
+static int cp_tm1217_read(struct cp_tm1217_device *ts,
+				u8 *req, int size)
+{
+	int i, retval;
+
+	/* Send the address */
+	retval = i2c_master_send(ts->client, &req[0], 1);
+	if (retval != 1) {
+		dev_err(ts->dev, "cp_tm1217: I2C send failed\n");
+		return retval;
+	}
+	msleep(WAIT_FOR_RESPONSE);
+	for (i = 0; i < MAX_RETRIES; i++) {
+		retval = i2c_master_recv(ts->client, &req[1], size);
+		if (retval == size) {
+			break;
+		} else {
+			msleep(INCREMENTAL_DELAY);
+			dev_dbg(ts->dev, "cp_tm1217: Retry count is %d\n", i);
+		}
+	}
+	if (retval != size)
+		dev_err(ts->dev, "cp_tm1217: Read from device failed\n");
+
+	return retval;
+}
+
+static int cp_tm1217_write(struct cp_tm1217_device *ts,
+				u8 *req, int size)
+{
+	int retval;
+
+	/* Send the address and the data to be written */
+	retval = i2c_master_send(ts->client, &req[0], size + 1);
+	if (retval != size + 1) {
+		dev_err(ts->dev, "cp_tm1217: I2C write  failed: %d\n", retval);
+		return retval;
+	}
+	/* Wait for the write to complete. TBD why this is required */
+	msleep(WAIT_FOR_RESPONSE);
+
+	return size;
+}
+
+static int cp_tm1217_mask_interrupt(struct cp_tm1217_device *ts)
+{
+	u8 req[2];
+	int retval;
+
+	req[0] = TMA1217_INTERRUPT_ENABLE;
+	req[1] = 0x0;
+	retval = cp_tm1217_write(ts, req, 1);
+	if (retval != 1)
+		return -EIO;
+
+	return 0;
+}
+
+static int cp_tm1217_unmask_interrupt(struct cp_tm1217_device *ts)
+{
+	u8 req[2];
+	int retval;
+
+	req[0] = TMA1217_INTERRUPT_ENABLE;
+	req[1] = 0xa;
+	retval = cp_tm1217_write(ts, req, 1);
+	if (retval != 1)
+		return -EIO;
+
+	return 0;
+}
+
+static void process_touch(struct cp_tm1217_device *ts, int index)
+{
+	int retval;
+	struct input_dev_info *input_info =
+		(struct input_dev_info *)&ts->cp_input_info[index];
+	u8 xy_data[6];
+
+	if (index == 0)
+		xy_data[0] = TMA1217_FINGER1_X_HIGHER8;
+	else
+		xy_data[0] = TMA1217_FINGER2_X_HIGHER8;
+
+	retval = cp_tm1217_read(ts, xy_data, 5);
+	if (retval < 5) {
+		dev_err(ts->dev, "cp_tm1217: XY read from device failed\n");
+		return;
+	}
+
+	/* Note: Currently not using the Z values but may be requried in
+	   the future. */
+	input_info->touch.x = (xy_data[1] << 4)
+					| (xy_data[3] & 0x0F);
+	input_info->touch.y = (xy_data[2] << 4)
+					| ((xy_data[3] & 0xF0) >> 4);
+	input_report_abs(input_info->input, ABS_X, input_info->touch.x);
+	input_report_abs(input_info->input, ABS_Y, input_info->touch.y);
+	input_sync(input_info->input);
+}
+
+static void cp_tm1217_get_data(struct cp_tm1217_device *ts)
+{
+	u8 req[2];
+	int retval, i, finger_touched = 0;
+
+	do {
+		req[0] = TMA1217_FINGER_STATE;
+		retval = cp_tm1217_read(ts, req, 1);
+		if (retval != 1) {
+			dev_err(ts->dev,
+				"cp_tm1217: Read from device failed\n");
+			continue;
+		}
+		finger_touched = 0;
+		/* Start sampling until the pressure is below
+		  threshold */
+		for (i = 0; i < TOUCH_SUPPORTED; i++) {
+			if (req[1] & 0x3) {
+				finger_touched++;
+				if (ts->cp_input_info[i].touch.button == 0) {
+					/* send the button touch event */
+					input_report_key(
+						ts->cp_input_info[i].input,
+						BTN_TOUCH, 1);
+					ts->cp_input_info[i].touch.button = 1;
+				}
+				process_touch(ts, i);
+			} else {
+				if (ts->cp_input_info[i].touch.button == 1) {
+					/* send the button release event */
+					input_report_key(
+						ts->cp_input_info[i].input,
+						BTN_TOUCH, 0);
+					input_sync(ts->cp_input_info[i].input);
+					ts->cp_input_info[i].touch.button = 0;
+				}
+			}
+			req[1] = req[1] >> 2;
+		}
+		msleep(DELAY_BTWIN_SAMPLE);
+	} while (finger_touched > 0);
+}
+
+static irqreturn_t cp_tm1217_sample_thread(int irq, void *handle)
+{
+	struct cp_tm1217_device *ts = (struct cp_tm1217_device *) handle;
+	u8 req[2];
+	int retval;
+
+	/* Chedk if another thread is already running */
+	mutex_lock(&ts->thread_mutex);
+	if (ts->thread_running == 1) {
+		mutex_unlock(&ts->thread_mutex);
+		return IRQ_HANDLED;
+	} else {
+		ts->thread_running = 1;
+		mutex_unlock(&ts->thread_mutex);
+	}
+
+	/* Mask the interrupts */
+	retval = cp_tm1217_mask_interrupt(ts);
+
+	/* Read the Interrupt Status register to find the cause of the
+	   Interrupt */
+	req[0] = TMA1217_INT_STATUS;
+	retval = cp_tm1217_read(ts, req, 1);
+	if (retval != 1)
+		goto exit_thread;
+
+	if (!(req[1] & 0x8))
+		goto exit_thread;
+
+	cp_tm1217_get_data(ts);
+
+exit_thread:
+	/* Unmask the interrupts before going to sleep */
+	retval = cp_tm1217_unmask_interrupt(ts);
+
+	mutex_lock(&ts->thread_mutex);
+	ts->thread_running = 0;
+	mutex_unlock(&ts->thread_mutex);
+
+	return IRQ_HANDLED;
+}
+
+static int cp_tm1217_init_data(struct cp_tm1217_device *ts)
+{
+	int retval;
+	u8	req[2];
+
+	/* Read the vendor id/ fw revision etc. Ignoring return check as this
+	   is non critical info  */
+	req[0] = TMA1217_MANUFACTURER_ID;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->vinfo.vendor_id = req[1];
+
+	req[0] = TMA1217_PRODUCT_FAMILY;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->vinfo.product_family = req[1];
+
+	req[0] = TMA1217_FIRMWARE_REVISION;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->vinfo.firmware_rev = req[1];
+
+	req[0] = TMA1217_SERIAL_NO_HIGH;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->vinfo.serial_no = (req[1] << 8);
+
+	req[0] = TMA1217_SERIAL_NO_LOW;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->vinfo.serial_no = ts->vinfo.serial_no | req[1];
+
+	req[0] = TMA1217_MAX_X_HIGHER4;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->dinfo.maxX = (req[1] & 0xF) << 8;
+
+	req[0] = TMA1217_MAX_X_LOWER8;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->dinfo.maxX = ts->dinfo.maxX | req[1];
+
+	req[0] = TMA1217_MAX_Y_HIGHER4;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->dinfo.maxY = (req[1] & 0xF) << 8;
+
+	req[0] = TMA1217_MAX_Y_LOWER8;
+	retval = cp_tm1217_read(ts, req, 1);
+	ts->dinfo.maxY = ts->dinfo.maxY | req[1];
+
+	return 0;
+
+}
+
+/*
+ *	Set up a GPIO for use as the interrupt. We can't simply do this at
+ *	boot time because the GPIO drivers themselves may not be around at
+ *	boot/firmware set up time to do the work. Instead defer it to driver
+ *	detection.
+ */
+
+static int cp_tm1217_setup_gpio_irq(struct cp_tm1217_device *ts)
+{
+	int retval;
+
+	/* Hook up the irq handler */
+	retval = gpio_request(ts->gpio, "cp_tm1217_touch");
+	if (retval < 0) {
+		dev_err(ts->dev, "cp_tm1217: GPIO request failed error %d\n",
+								retval);
+		return retval;
+	}
+
+	retval = gpio_direction_input(ts->gpio);
+	if (retval < 0) {
+		dev_err(ts->dev,
+		"cp_tm1217: GPIO direction configuration failed, error %d\n",
+								retval);
+		gpio_free(ts->gpio);
+		return retval;
+	}
+
+	retval = gpio_to_irq(ts->gpio);
+	if (retval < 0) {
+		dev_err(ts->dev, "cp_tm1217: GPIO to IRQ failedi,"
+		" error %d\n", retval);
+		gpio_free(ts->gpio);
+	}
+	dev_dbg(ts->dev,
+		"cp_tm1217: Got IRQ number is %d for GPIO %d\n",
+		retval, ts->gpio);
+	return retval;
+}
+
+static int cp_tm1217_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct cp_tm1217_device *ts;
+	struct input_dev *input_dev;
+	struct input_dev_info	*input_info;
+	struct cp_tm1217_platform_data *pdata;
+	u8 req[2];
+	int i, retval;
+
+	/* No pdata is fine - we then use "normal" IRQ mode */
+
+	pdata = client->dev.platform_data;
+
+	ts = kzalloc(sizeof(struct cp_tm1217_device), GFP_KERNEL);
+	if (!ts) {
+		dev_err(&client->dev,
+			"cp_tm1217: Private Device Struct alloc failed\n");
+		return -ENOMEM;
+	}
+
+	ts->client = client;
+	ts->dev = &client->dev;
+	i2c_set_clientdata(client, ts);
+
+	ts->thread_running = 0;
+	mutex_init(&ts->thread_mutex);
+
+	/* Reset the Controller */
+	req[0] = TMA1217_DEVICE_CMD_RESET;
+	req[1] = 0x1;
+	retval = cp_tm1217_write(ts, req, 1);
+	if (retval != 1) {
+		dev_err(ts->dev, "cp_tm1217: Controller reset failed\n");
+		kfree(ts);
+		return -EIO;
+	}
+
+	/* Clear up the interrupt status from reset. */
+	req[0] = TMA1217_INT_STATUS;
+	retval = cp_tm1217_read(ts, req, 1);
+
+	/* Mask all the interrupts */
+	retval = cp_tm1217_mask_interrupt(ts);
+
+	/* Read the controller information */
+	cp_tm1217_init_data(ts);
+
+	/* The following code will register multiple event devices when
+	   multi-pointer is enabled, the code has not been tested
+	   with MPX */
+	for (i = 0; i < TOUCH_SUPPORTED; i++) {
+		input_dev = input_allocate_device();
+		if (input_dev == NULL) {
+			kfree(ts);
+			dev_err(ts->dev,
+				"cp_tm1217:Input Device Struct alloc failed\n");
+			return -ENOMEM;
+		}
+		input_info = &ts->cp_input_info[i];
+		snprintf(input_info->name, sizeof(input_info->name),
+			"cp_tm1217_touchscreen_%d", i);
+		input_dev->name = input_info->name;
+		snprintf(input_info->phys, sizeof(input_info->phys),
+			"%s/input%d", dev_name(&client->dev), i);
+
+		input_dev->phys = input_info->phys;
+		input_dev->id.bustype = BUS_I2C;
+
+		input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+		input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+		input_set_abs_params(input_dev, ABS_X, 0, ts->dinfo.maxX, 0, 0);
+		input_set_abs_params(input_dev, ABS_Y, 0, ts->dinfo.maxY, 0, 0);
+
+		retval = input_register_device(input_dev);
+		if (retval) {
+			dev_err(ts->dev,
+				"Input dev registration failed for %s\n",
+					input_dev->name);
+			goto fail;
+		}
+		input_info->input = input_dev;
+	}
+
+	/* Setup the reporting mode to send an interrupt only when
+	   finger arrives or departs. */
+	req[0] = TMA1217_REPORT_MODE;
+	req[1] = 0x02;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	/* Setup the device to no sleep mode for now and make it configured */
+	req[0] = TMA1217_DEVICE_CTRL;
+	req[1] = 0x84;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	/* Check for the status of the device */
+	req[0] = TMA1217_DEV_STATUS;
+	retval = cp_tm1217_read(ts, req, 1);
+	if (req[1] != 0) {
+		dev_err(ts->dev,
+			"cp_tm1217: Device Status 0x%x != 0: config failed\n",
+			req[1]);
+
+		retval = -EIO;
+		goto fail;
+	}
+
+	if (pdata && pdata->gpio) {
+		ts->gpio = pdata->gpio;
+		retval = cp_tm1217_setup_gpio_irq(ts);
+	} else
+		retval = client->irq;
+
+	if (retval < 0) {
+		dev_err(ts->dev, "cp_tm1217: GPIO request failed error %d\n",
+								retval);
+		goto fail;
+	}
+
+	client->irq = retval;
+
+
+	retval = request_threaded_irq(client->irq,
+		NULL, cp_tm1217_sample_thread,
+		IRQF_TRIGGER_FALLING, "cp_tm1217_touch", ts);
+	if (retval < 0) {
+		dev_err(ts->dev, "cp_tm1217: Request IRQ error %d\n", retval);
+		goto fail_gpio;
+	}
+
+	/* Unmask the interrupts */
+	retval = cp_tm1217_unmask_interrupt(ts);
+	if (retval == 0)
+		return 0;
+
+	free_irq(client->irq, ts);
+fail_gpio:
+	if (ts->gpio)
+		gpio_free(ts->gpio);
+fail:
+	/* Clean up before returning failure */
+	for (i = 0; i < TOUCH_SUPPORTED; i++) {
+		if (ts->cp_input_info[i].input) {
+			input_unregister_device(ts->cp_input_info[i].input);
+			input_free_device(ts->cp_input_info[i].input);
+		}
+	}
+	kfree(ts);
+	return retval;
+
+}
+
+/*
+ * cp_tm1217 suspend
+ *
+ */
+static int cp_tm1217_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+	struct cp_tm1217_device *ts = i2c_get_clientdata(client);
+	u8 req[2];
+	int retval;
+
+	/* Put the controller to sleep */
+	req[0] = TMA1217_DEVICE_CTRL;
+	retval = cp_tm1217_read(ts, req, 1);
+	req[1] = (req[1] & 0xF8) | 0x1;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	if (device_may_wakeup(&client->dev))
+		enable_irq_wake(client->irq);
+
+	return 0;
+}
+
+/*
+ * cp_tm1217_resume
+ *
+ */
+static int cp_tm1217_resume(struct i2c_client *client)
+{
+	struct cp_tm1217_device *ts = i2c_get_clientdata(client);
+	u8 req[2];
+	int retval;
+
+	/* Take the controller out of sleep */
+	req[0] = TMA1217_DEVICE_CTRL;
+	retval = cp_tm1217_read(ts, req, 1);
+	req[1] = (req[1] & 0xF8) | 0x4;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	/* Restore the register settings sinc the power to the
+	   could have been cut off */
+
+	/* Setup the reporting mode to send an interrupt only when
+	   finger arrives or departs. */
+	req[0] = TMA1217_REPORT_MODE;
+	req[1] = 0x02;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	/* Setup the device to no sleep mode for now and make it configured */
+	req[0] = TMA1217_DEVICE_CTRL;
+	req[1] = 0x84;
+	retval = cp_tm1217_write(ts, req, 1);
+
+	/* Setup the interrupt mask */
+	retval = cp_tm1217_unmask_interrupt(ts);
+
+	if (device_may_wakeup(&client->dev))
+		disable_irq_wake(client->irq);
+
+	return 0;
+}
+
+/*
+ * cp_tm1217_remove
+ *
+ */
+static int cp_tm1217_remove(struct i2c_client *client)
+{
+	struct cp_tm1217_device *ts = i2c_get_clientdata(client);
+	int i;
+
+	free_irq(client->irq, ts);
+	if (ts->gpio)
+		gpio_free(ts->gpio);
+	for (i = 0; i < TOUCH_SUPPORTED; i++)
+		input_unregister_device(ts->cp_input_info[i].input);
+	kfree(ts);
+	return 0;
+}
+
+static struct i2c_device_id cp_tm1217_idtable[] = {
+	{ CPTM1217_DEVICE_NAME, 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, cp_tm1217_idtable);
+
+static struct i2c_driver cp_tm1217_driver = {
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= CPTM1217_DRIVER_NAME,
+	},
+	.id_table	= cp_tm1217_idtable,
+	.probe		= cp_tm1217_probe,
+	.remove		= cp_tm1217_remove,
+	.suspend    = cp_tm1217_suspend,
+	.resume     = cp_tm1217_resume,
+};
+
+static int __init clearpad_tm1217_init(void)
+{
+	return i2c_add_driver(&cp_tm1217_driver);
+}
+
+static void __exit clearpad_tm1217_exit(void)
+{
+	i2c_del_driver(&cp_tm1217_driver);
+}
+
+module_init(clearpad_tm1217_init);
+module_exit(clearpad_tm1217_exit);
+
+MODULE_AUTHOR("Ramesh Agarwal <ramesh.agarwal@intel.com>");
+MODULE_DESCRIPTION("Synaptics TM1217 TouchScreen Driver");
+MODULE_LICENSE("GPL v2");

drivers/staging/cptm1217/cp_tm1217.h

@@ -0,0 +1,9 @@
+#ifndef __LINUX_I2C_CP_TM1217_H
+#define __LINUX_I2C_CP_TM1217_H
+
+struct cp_tm1217_platform_data
+{
+	int gpio;		/* If not set uses the IRQ resource 0 */
+};
+
+#endif