Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 964 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/zforce_ts.c b/drivers/input/touchscreen/zforce_ts.c
new file mode 100644
index 000000000..7b3845aa5
--- /dev/null
+++ b/drivers/input/touchscreen/zforce_ts.c
@@ -0,0 +1,964 @@
+/*
+ * Copyright (C) 2012-2013 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ *
+ * based in parts on Nook zforce driver
+ *
+ * Copyright (C) 2010 Barnes & Noble, Inc.
+ * Author: Pieter Truter<ptruter@intrinsyc.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/hrtimer.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+#include <linux/input/mt.h>
+#include <linux/platform_data/zforce_ts.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of.h>
+
+#define WAIT_TIMEOUT		msecs_to_jiffies(1000)
+
+#define FRAME_START		0xee
+#define FRAME_MAXSIZE		257
+
+/* Offsets of the different parts of the payload the controller sends */
+#define PAYLOAD_HEADER		0
+#define PAYLOAD_LENGTH		1
+#define PAYLOAD_BODY		2
+
+/* Response offsets */
+#define RESPONSE_ID		0
+#define RESPONSE_DATA		1
+
+/* Commands */
+#define COMMAND_DEACTIVATE	0x00
+#define COMMAND_INITIALIZE	0x01
+#define COMMAND_RESOLUTION	0x02
+#define COMMAND_SETCONFIG	0x03
+#define COMMAND_DATAREQUEST	0x04
+#define COMMAND_SCANFREQ	0x08
+#define COMMAND_STATUS		0X1e
+
+/*
+ * Responses the controller sends as a result of
+ * command requests
+ */
+#define RESPONSE_DEACTIVATE	0x00
+#define RESPONSE_INITIALIZE	0x01
+#define RESPONSE_RESOLUTION	0x02
+#define RESPONSE_SETCONFIG	0x03
+#define RESPONSE_SCANFREQ	0x08
+#define RESPONSE_STATUS		0X1e
+
+/*
+ * Notifications are sent by the touch controller without
+ * being requested by the driver and include for example
+ * touch indications
+ */
+#define NOTIFICATION_TOUCH		0x04
+#define NOTIFICATION_BOOTCOMPLETE	0x07
+#define NOTIFICATION_OVERRUN		0x25
+#define NOTIFICATION_PROXIMITY		0x26
+#define NOTIFICATION_INVALID_COMMAND	0xfe
+
+#define ZFORCE_REPORT_POINTS		2
+#define ZFORCE_MAX_AREA			0xff
+
+#define STATE_DOWN			0
+#define STATE_MOVE			1
+#define STATE_UP			2
+
+#define SETCONFIG_DUALTOUCH		(1 << 0)
+
+struct zforce_point {
+	int coord_x;
+	int coord_y;
+	int state;
+	int id;
+	int area_major;
+	int area_minor;
+	int orientation;
+	int pressure;
+	int prblty;
+};
+
+/*
+ * @client		the i2c_client
+ * @input		the input device
+ * @suspending		in the process of going to suspend (don't emit wakeup
+ *			events for commands executed to suspend the device)
+ * @suspended		device suspended
+ * @access_mutex	serialize i2c-access, to keep multipart reads together
+ * @command_done	completion to wait for the command result
+ * @command_mutex	serialize commands sent to the ic
+ * @command_waiting	the id of the command that is currently waiting
+ *			for a result
+ * @command_result	returned result of the command
+ */
+struct zforce_ts {
+	struct i2c_client	*client;
+	struct input_dev	*input;
+	const struct zforce_ts_platdata *pdata;
+	char			phys[32];
+
+	struct regulator	*reg_vdd;
+
+	struct gpio_desc	*gpio_int;
+	struct gpio_desc	*gpio_rst;
+
+	bool			suspending;
+	bool			suspended;
+	bool			boot_complete;
+
+	/* Firmware version information */
+	u16			version_major;
+	u16			version_minor;
+	u16			version_build;
+	u16			version_rev;
+
+	struct mutex		access_mutex;
+
+	struct completion	command_done;
+	struct mutex		command_mutex;
+	int			command_waiting;
+	int			command_result;
+};
+
+static int zforce_command(struct zforce_ts *ts, u8 cmd)
+{
+	struct i2c_client *client = ts->client;
+	char buf[3];
+	int ret;
+
+	dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
+
+	buf[0] = FRAME_START;
+	buf[1] = 1; /* data size, command only */
+	buf[2] = cmd;
+
+	mutex_lock(&ts->access_mutex);
+	ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
+	mutex_unlock(&ts->access_mutex);
+	if (ret < 0) {
+		dev_err(&client->dev, "i2c send data request error: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void zforce_reset_assert(struct zforce_ts *ts)
+{
+	gpiod_set_value_cansleep(ts->gpio_rst, 1);
+}
+
+static void zforce_reset_deassert(struct zforce_ts *ts)
+{
+	gpiod_set_value_cansleep(ts->gpio_rst, 0);
+}
+
+static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
+{
+	struct i2c_client *client = ts->client;
+	int ret;
+
+	ret = mutex_trylock(&ts->command_mutex);
+	if (!ret) {
+		dev_err(&client->dev, "already waiting for a command\n");
+		return -EBUSY;
+	}
+
+	dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
+		buf[1], buf[2]);
+
+	ts->command_waiting = buf[2];
+
+	mutex_lock(&ts->access_mutex);
+	ret = i2c_master_send(client, buf, len);
+	mutex_unlock(&ts->access_mutex);
+	if (ret < 0) {
+		dev_err(&client->dev, "i2c send data request error: %d\n", ret);
+		goto unlock;
+	}
+
+	dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
+
+	if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
+		ret = -ETIME;
+		goto unlock;
+	}
+
+	ret = ts->command_result;
+
+unlock:
+	mutex_unlock(&ts->command_mutex);
+	return ret;
+}
+
+static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
+{
+	struct i2c_client *client = ts->client;
+	char buf[3];
+	int ret;
+
+	dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
+
+	buf[0] = FRAME_START;
+	buf[1] = 1; /* data size, command only */
+	buf[2] = cmd;
+
+	ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
+	if (ret < 0) {
+		dev_err(&client->dev, "i2c send data request error: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
+{
+	struct i2c_client *client = ts->client;
+	char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
+			(x & 0xff), ((x >> 8) & 0xff),
+			(y & 0xff), ((y >> 8) & 0xff) };
+
+	dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
+
+	return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
+}
+
+static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
+				 u16 stylus)
+{
+	struct i2c_client *client = ts->client;
+	char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
+			(idle & 0xff), ((idle >> 8) & 0xff),
+			(finger & 0xff), ((finger >> 8) & 0xff),
+			(stylus & 0xff), ((stylus >> 8) & 0xff) };
+
+	dev_dbg(&client->dev,
+		"set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
+		idle, finger, stylus);
+
+	return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
+}
+
+static int zforce_setconfig(struct zforce_ts *ts, char b1)
+{
+	struct i2c_client *client = ts->client;
+	char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
+			b1, 0, 0, 0 };
+
+	dev_dbg(&client->dev, "set config to (%d)\n", b1);
+
+	return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
+}
+
+static int zforce_start(struct zforce_ts *ts)
+{
+	struct i2c_client *client = ts->client;
+	const struct zforce_ts_platdata *pdata = ts->pdata;
+	int ret;
+
+	dev_dbg(&client->dev, "starting device\n");
+
+	ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
+	if (ret) {
+		dev_err(&client->dev, "Unable to initialize, %d\n", ret);
+		return ret;
+	}
+
+	ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
+	if (ret) {
+		dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
+		goto error;
+	}
+
+	ret = zforce_scan_frequency(ts, 10, 50, 50);
+	if (ret) {
+		dev_err(&client->dev, "Unable to set scan frequency, %d\n",
+			ret);
+		goto error;
+	}
+
+	ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
+	if (ret) {
+		dev_err(&client->dev, "Unable to set config\n");
+		goto error;
+	}
+
+	/* start sending touch events */
+	ret = zforce_command(ts, COMMAND_DATAREQUEST);
+	if (ret) {
+		dev_err(&client->dev, "Unable to request data\n");
+		goto error;
+	}
+
+	/*
+	 * Per NN, initial cal. take max. of 200msec.
+	 * Allow time to complete this calibration
+	 */
+	msleep(200);
+
+	return 0;
+
+error:
+	zforce_command_wait(ts, COMMAND_DEACTIVATE);
+	return ret;
+}
+
+static int zforce_stop(struct zforce_ts *ts)
+{
+	struct i2c_client *client = ts->client;
+	int ret;
+
+	dev_dbg(&client->dev, "stopping device\n");
+
+	/* Deactivates touch sensing and puts the device into sleep. */
+	ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
+	if (ret != 0) {
+		dev_err(&client->dev, "could not deactivate device, %d\n",
+			ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
+{
+	struct i2c_client *client = ts->client;
+	const struct zforce_ts_platdata *pdata = ts->pdata;
+	struct zforce_point point;
+	int count, i, num = 0;
+
+	count = payload[0];
+	if (count > ZFORCE_REPORT_POINTS) {
+		dev_warn(&client->dev,
+			 "too many coordinates %d, expected max %d\n",
+			 count, ZFORCE_REPORT_POINTS);
+		count = ZFORCE_REPORT_POINTS;
+	}
+
+	for (i = 0; i < count; i++) {
+		point.coord_x =
+			payload[9 * i + 2] << 8 | payload[9 * i + 1];
+		point.coord_y =
+			payload[9 * i + 4] << 8 | payload[9 * i + 3];
+
+		if (point.coord_x > pdata->x_max ||
+		    point.coord_y > pdata->y_max) {
+			dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
+				point.coord_x, point.coord_y);
+			point.coord_x = point.coord_y = 0;
+		}
+
+		point.state = payload[9 * i + 5] & 0x0f;
+		point.id = (payload[9 * i + 5] & 0xf0) >> 4;
+
+		/* determine touch major, minor and orientation */
+		point.area_major = max(payload[9 * i + 6],
+					  payload[9 * i + 7]);
+		point.area_minor = min(payload[9 * i + 6],
+					  payload[9 * i + 7]);
+		point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
+
+		point.pressure = payload[9 * i + 8];
+		point.prblty = payload[9 * i + 9];
+
+		dev_dbg(&client->dev,
+			"point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
+			i, count, point.state, point.id,
+			point.pressure, point.prblty,
+			point.coord_x, point.coord_y,
+			point.area_major, point.area_minor,
+			point.orientation);
+
+		/* the zforce id starts with "1", so needs to be decreased */
+		input_mt_slot(ts->input, point.id - 1);
+
+		input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
+						point.state != STATE_UP);
+
+		if (point.state != STATE_UP) {
+			input_report_abs(ts->input, ABS_MT_POSITION_X,
+					 point.coord_x);
+			input_report_abs(ts->input, ABS_MT_POSITION_Y,
+					 point.coord_y);
+			input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
+					 point.area_major);
+			input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
+					 point.area_minor);
+			input_report_abs(ts->input, ABS_MT_ORIENTATION,
+					 point.orientation);
+			num++;
+		}
+	}
+
+	input_mt_sync_frame(ts->input);
+
+	input_mt_report_finger_count(ts->input, num);
+
+	input_sync(ts->input);
+
+	return 0;
+}
+
+static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
+{
+	struct i2c_client *client = ts->client;
+	int ret;
+
+	mutex_lock(&ts->access_mutex);
+
+	/* read 2 byte message header */
+	ret = i2c_master_recv(client, buf, 2);
+	if (ret < 0) {
+		dev_err(&client->dev, "error reading header: %d\n", ret);
+		goto unlock;
+	}
+
+	if (buf[PAYLOAD_HEADER] != FRAME_START) {
+		dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
+		ret = -EIO;
+		goto unlock;
+	}
+
+	if (buf[PAYLOAD_LENGTH] == 0) {
+		dev_err(&client->dev, "invalid payload length: %d\n",
+			buf[PAYLOAD_LENGTH]);
+		ret = -EIO;
+		goto unlock;
+	}
+
+	/* read the message */
+	ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
+	if (ret < 0) {
+		dev_err(&client->dev, "error reading payload: %d\n", ret);
+		goto unlock;
+	}
+
+	dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
+		buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
+
+unlock:
+	mutex_unlock(&ts->access_mutex);
+	return ret;
+}
+
+static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
+{
+	struct i2c_client *client = ts->client;
+
+	if (ts->command_waiting == cmd) {
+		dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
+		ts->command_result = result;
+		complete(&ts->command_done);
+	} else {
+		dev_dbg(&client->dev, "command %d not for us\n", cmd);
+	}
+}
+
+static irqreturn_t zforce_irq(int irq, void *dev_id)
+{
+	struct zforce_ts *ts = dev_id;
+	struct i2c_client *client = ts->client;
+
+	if (ts->suspended && device_may_wakeup(&client->dev))
+		pm_wakeup_event(&client->dev, 500);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
+{
+	struct zforce_ts *ts = dev_id;
+	struct i2c_client *client = ts->client;
+	int ret;
+	u8 payload_buffer[FRAME_MAXSIZE];
+	u8 *payload;
+
+	/*
+	 * When still suspended, return.
+	 * Due to the level-interrupt we will get re-triggered later.
+	 */
+	if (ts->suspended) {
+		msleep(20);
+		return IRQ_HANDLED;
+	}
+
+	dev_dbg(&client->dev, "handling interrupt\n");
+
+	/* Don't emit wakeup events from commands run by zforce_suspend */
+	if (!ts->suspending && device_may_wakeup(&client->dev))
+		pm_stay_awake(&client->dev);
+
+	/*
+	 * Run at least once and exit the loop if
+	 * - the optional interrupt GPIO isn't specified
+	 *   (there is only one packet read per ISR invocation, then)
+	 * or
+	 * - the GPIO isn't active any more
+	 *   (packet read until the level GPIO indicates that there is
+	 *    no IRQ any more)
+	 */
+	do {
+		ret = zforce_read_packet(ts, payload_buffer);
+		if (ret < 0) {
+			dev_err(&client->dev,
+				"could not read packet, ret: %d\n", ret);
+			break;
+		}
+
+		payload =  &payload_buffer[PAYLOAD_BODY];
+
+		switch (payload[RESPONSE_ID]) {
+		case NOTIFICATION_TOUCH:
+			/*
+			 * Always report touch-events received while
+			 * suspending, when being a wakeup source
+			 */
+			if (ts->suspending && device_may_wakeup(&client->dev))
+				pm_wakeup_event(&client->dev, 500);
+			zforce_touch_event(ts, &payload[RESPONSE_DATA]);
+			break;
+
+		case NOTIFICATION_BOOTCOMPLETE:
+			ts->boot_complete = payload[RESPONSE_DATA];
+			zforce_complete(ts, payload[RESPONSE_ID], 0);
+			break;
+
+		case RESPONSE_INITIALIZE:
+		case RESPONSE_DEACTIVATE:
+		case RESPONSE_SETCONFIG:
+		case RESPONSE_RESOLUTION:
+		case RESPONSE_SCANFREQ:
+			zforce_complete(ts, payload[RESPONSE_ID],
+					payload[RESPONSE_DATA]);
+			break;
+
+		case RESPONSE_STATUS:
+			/*
+			 * Version Payload Results
+			 * [2:major] [2:minor] [2:build] [2:rev]
+			 */
+			ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
+						payload[RESPONSE_DATA];
+			ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
+						payload[RESPONSE_DATA + 2];
+			ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
+						payload[RESPONSE_DATA + 4];
+			ts->version_rev   = (payload[RESPONSE_DATA + 7] << 8) |
+						payload[RESPONSE_DATA + 6];
+			dev_dbg(&ts->client->dev,
+				"Firmware Version %04x:%04x %04x:%04x\n",
+				ts->version_major, ts->version_minor,
+				ts->version_build, ts->version_rev);
+
+			zforce_complete(ts, payload[RESPONSE_ID], 0);
+			break;
+
+		case NOTIFICATION_INVALID_COMMAND:
+			dev_err(&ts->client->dev, "invalid command: 0x%x\n",
+				payload[RESPONSE_DATA]);
+			break;
+
+		default:
+			dev_err(&ts->client->dev,
+				"unrecognized response id: 0x%x\n",
+				payload[RESPONSE_ID]);
+			break;
+		}
+	} while (gpiod_get_value_cansleep(ts->gpio_int));
+
+	if (!ts->suspending && device_may_wakeup(&client->dev))
+		pm_relax(&client->dev);
+
+	dev_dbg(&client->dev, "finished interrupt\n");
+
+	return IRQ_HANDLED;
+}
+
+static int zforce_input_open(struct input_dev *dev)
+{
+	struct zforce_ts *ts = input_get_drvdata(dev);
+
+	return zforce_start(ts);
+}
+
+static void zforce_input_close(struct input_dev *dev)
+{
+	struct zforce_ts *ts = input_get_drvdata(dev);
+	struct i2c_client *client = ts->client;
+	int ret;
+
+	ret = zforce_stop(ts);
+	if (ret)
+		dev_warn(&client->dev, "stopping zforce failed\n");
+
+	return;
+}
+
+static int __maybe_unused zforce_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct zforce_ts *ts = i2c_get_clientdata(client);
+	struct input_dev *input = ts->input;
+	int ret = 0;
+
+	mutex_lock(&input->mutex);
+	ts->suspending = true;
+
+	/*
+	 * When configured as a wakeup source device should always wake
+	 * the system, therefore start device if necessary.
+	 */
+	if (device_may_wakeup(&client->dev)) {
+		dev_dbg(&client->dev, "suspend while being a wakeup source\n");
+
+		/* Need to start device, if not open, to be a wakeup source. */
+		if (!input->users) {
+			ret = zforce_start(ts);
+			if (ret)
+				goto unlock;
+		}
+
+		enable_irq_wake(client->irq);
+	} else if (input->users) {
+		dev_dbg(&client->dev,
+			"suspend without being a wakeup source\n");
+
+		ret = zforce_stop(ts);
+		if (ret)
+			goto unlock;
+
+		disable_irq(client->irq);
+	}
+
+	ts->suspended = true;
+
+unlock:
+	ts->suspending = false;
+	mutex_unlock(&input->mutex);
+
+	return ret;
+}
+
+static int __maybe_unused zforce_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct zforce_ts *ts = i2c_get_clientdata(client);
+	struct input_dev *input = ts->input;
+	int ret = 0;
+
+	mutex_lock(&input->mutex);
+
+	ts->suspended = false;
+
+	if (device_may_wakeup(&client->dev)) {
+		dev_dbg(&client->dev, "resume from being a wakeup source\n");
+
+		disable_irq_wake(client->irq);
+
+		/* need to stop device if it was not open on suspend */
+		if (!input->users) {
+			ret = zforce_stop(ts);
+			if (ret)
+				goto unlock;
+		}
+	} else if (input->users) {
+		dev_dbg(&client->dev, "resume without being a wakeup source\n");
+
+		enable_irq(client->irq);
+
+		ret = zforce_start(ts);
+		if (ret < 0)
+			goto unlock;
+	}
+
+unlock:
+	mutex_unlock(&input->mutex);
+
+	return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
+
+static void zforce_reset(void *data)
+{
+	struct zforce_ts *ts = data;
+
+	zforce_reset_assert(ts);
+
+	udelay(10);
+
+	if (!IS_ERR(ts->reg_vdd))
+		regulator_disable(ts->reg_vdd);
+}
+
+static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
+{
+	struct zforce_ts_platdata *pdata;
+	struct device_node *np = dev->of_node;
+
+	if (!np)
+		return ERR_PTR(-ENOENT);
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(dev, "failed to allocate platform data\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	if (of_property_read_u32(np, "x-size", &pdata->x_max)) {
+		dev_err(dev, "failed to get x-size property\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(np, "y-size", &pdata->y_max)) {
+		dev_err(dev, "failed to get y-size property\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	return pdata;
+}
+
+static int zforce_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
+	struct zforce_ts *ts;
+	struct input_dev *input_dev;
+	int ret;
+
+	if (!pdata) {
+		pdata = zforce_parse_dt(&client->dev);
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
+	}
+
+	ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	ts->gpio_rst = devm_gpiod_get_optional(&client->dev, "reset",
+					       GPIOD_OUT_HIGH);
+	if (IS_ERR(ts->gpio_rst)) {
+		ret = PTR_ERR(ts->gpio_rst);
+		dev_err(&client->dev,
+			"failed to request reset GPIO: %d\n", ret);
+		return ret;
+	}
+
+	if (ts->gpio_rst) {
+		ts->gpio_int = devm_gpiod_get_optional(&client->dev, "irq",
+						       GPIOD_IN);
+		if (IS_ERR(ts->gpio_int)) {
+			ret = PTR_ERR(ts->gpio_int);
+			dev_err(&client->dev,
+				"failed to request interrupt GPIO: %d\n", ret);
+			return ret;
+		}
+	} else {
+		/*
+		 * Deprecated GPIO handling for compatibility
+		 * with legacy binding.
+		 */
+
+		/* INT GPIO */
+		ts->gpio_int = devm_gpiod_get_index(&client->dev, NULL, 0,
+						    GPIOD_IN);
+		if (IS_ERR(ts->gpio_int)) {
+			ret = PTR_ERR(ts->gpio_int);
+			dev_err(&client->dev,
+				"failed to request interrupt GPIO: %d\n", ret);
+			return ret;
+		}
+
+		/* RST GPIO */
+		ts->gpio_rst = devm_gpiod_get_index(&client->dev, NULL, 1,
+					    GPIOD_OUT_HIGH);
+		if (IS_ERR(ts->gpio_rst)) {
+			ret = PTR_ERR(ts->gpio_rst);
+			dev_err(&client->dev,
+				"failed to request reset GPIO: %d\n", ret);
+			return ret;
+		}
+	}
+
+	ts->reg_vdd = devm_regulator_get_optional(&client->dev, "vdd");
+	if (IS_ERR(ts->reg_vdd)) {
+		ret = PTR_ERR(ts->reg_vdd);
+		if (ret == -EPROBE_DEFER)
+			return ret;
+	} else {
+		ret = regulator_enable(ts->reg_vdd);
+		if (ret)
+			return ret;
+
+		/*
+		 * according to datasheet add 100us grace time after regular
+		 * regulator enable delay.
+		 */
+		udelay(100);
+	}
+
+	ret = devm_add_action(&client->dev, zforce_reset, ts);
+	if (ret) {
+		dev_err(&client->dev, "failed to register reset action, %d\n",
+			ret);
+
+		/* hereafter the regulator will be disabled by the action */
+		if (!IS_ERR(ts->reg_vdd))
+			regulator_disable(ts->reg_vdd);
+
+		return ret;
+	}
+
+	snprintf(ts->phys, sizeof(ts->phys),
+		 "%s/input0", dev_name(&client->dev));
+
+	input_dev = devm_input_allocate_device(&client->dev);
+	if (!input_dev) {
+		dev_err(&client->dev, "could not allocate input device\n");
+		return -ENOMEM;
+	}
+
+	mutex_init(&ts->access_mutex);
+	mutex_init(&ts->command_mutex);
+
+	ts->pdata = pdata;
+	ts->client = client;
+	ts->input = input_dev;
+
+	input_dev->name = "Neonode zForce touchscreen";
+	input_dev->phys = ts->phys;
+	input_dev->id.bustype = BUS_I2C;
+
+	input_dev->open = zforce_input_open;
+	input_dev->close = zforce_input_close;
+
+	__set_bit(EV_KEY, input_dev->evbit);
+	__set_bit(EV_SYN, input_dev->evbit);
+	__set_bit(EV_ABS, input_dev->evbit);
+
+	/* For multi touch */
+	input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
+			     pdata->x_max, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
+			     pdata->y_max, 0, 0);
+
+	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
+			     ZFORCE_MAX_AREA, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
+			     ZFORCE_MAX_AREA, 0, 0);
+	input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
+	input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
+
+	input_set_drvdata(ts->input, ts);
+
+	init_completion(&ts->command_done);
+
+	/*
+	 * The zforce pulls the interrupt low when it has data ready.
+	 * After it is triggered the isr thread runs until all the available
+	 * packets have been read and the interrupt is high again.
+	 * Therefore we can trigger the interrupt anytime it is low and do
+	 * not need to limit it to the interrupt edge.
+	 */
+	ret = devm_request_threaded_irq(&client->dev, client->irq,
+					zforce_irq, zforce_irq_thread,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					input_dev->name, ts);
+	if (ret) {
+		dev_err(&client->dev, "irq %d request failed\n", client->irq);
+		return ret;
+	}
+
+	i2c_set_clientdata(client, ts);
+
+	/* let the controller boot */
+	zforce_reset_deassert(ts);
+
+	ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
+	if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
+		dev_warn(&client->dev, "bootcomplete timed out\n");
+
+	/* need to start device to get version information */
+	ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
+	if (ret) {
+		dev_err(&client->dev, "unable to initialize, %d\n", ret);
+		return ret;
+	}
+
+	/* this gets the firmware version among other information */
+	ret = zforce_command_wait(ts, COMMAND_STATUS);
+	if (ret < 0) {
+		dev_err(&client->dev, "couldn't get status, %d\n", ret);
+		zforce_stop(ts);
+		return ret;
+	}
+
+	/* stop device and put it into sleep until it is opened */
+	ret = zforce_stop(ts);
+	if (ret < 0)
+		return ret;
+
+	device_set_wakeup_capable(&client->dev, true);
+
+	ret = input_register_device(input_dev);
+	if (ret) {
+		dev_err(&client->dev, "could not register input device, %d\n",
+			ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct i2c_device_id zforce_idtable[] = {
+	{ "zforce-ts", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, zforce_idtable);
+
+#ifdef CONFIG_OF
+static const struct of_device_id zforce_dt_idtable[] = {
+	{ .compatible = "neonode,zforce" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
+#endif
+
+static struct i2c_driver zforce_driver = {
+	.driver = {
+		.name	= "zforce-ts",
+		.pm	= &zforce_pm_ops,
+		.of_match_table	= of_match_ptr(zforce_dt_idtable),
+	},
+	.probe		= zforce_probe,
+	.id_table	= zforce_idtable,
+};
+
+module_i2c_driver(zforce_driver);
+
+MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
+MODULE_DESCRIPTION("zForce TouchScreen Driver");
+MODULE_LICENSE("GPL");