diff mbox

[PATCHv9,1/3] Input: tsc2007: Add device tree support.

Message ID 1383916659-9988-1-git-send-email-denis@eukrea.com (mailing list archive)
State New, archived
Headers show

Commit Message

Denis Carikli Nov. 8, 2013, 1:17 p.m. UTC
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: devicetree@vger.kernel.org
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: linux-input@vger.kernel.org
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Eric Bénard <eric@eukrea.com>
Signed-off-by: Denis Carikli <denis@eukrea.com>
---
ChangeLog v8->v9:
- Added Grant Likely in the Cc list.
- Removed the mention of the pinctrl properties in the documentation.

ChangeLog v7->v8:
- Fixed the lack of x and z fuzz properties.
- The pendown gpio is better documented.
- Added Shawn Guo in the cc list.
---
 .../bindings/input/touchscreen/tsc2007.txt         |   41 ++++
 drivers/input/touchscreen/tsc2007.c                |  204 ++++++++++++++++----
 2 files changed, 204 insertions(+), 41 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt

Comments

Jean-Christophe PLAGNIOL-VILLARD Nov. 21, 2013, 5:05 a.m. UTC | #1
On 14:17 Fri 08 Nov     , Denis Carikli wrote:
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: devicetree@vger.kernel.org
> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Cc: linux-input@vger.kernel.org
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: Lothar Waßmann <LW@KARO-electronics.de>
> Cc: Shawn Guo <shawn.guo@linaro.org>
> Cc: Eric Bénard <eric@eukrea.com>
> Signed-off-by: Denis Carikli <denis@eukrea.com>
> ---
> ChangeLog v8->v9:
> - Added Grant Likely in the Cc list.
> - Removed the mention of the pinctrl properties in the documentation.
> 
> ChangeLog v7->v8:
> - Fixed the lack of x and z fuzz properties.
> - The pendown gpio is better documented.
> - Added Shawn Guo in the cc list.
> ---
>  .../bindings/input/touchscreen/tsc2007.txt         |   41 ++++
>  drivers/input/touchscreen/tsc2007.c                |  204 ++++++++++++++++----
>  2 files changed, 204 insertions(+), 41 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
> new file mode 100644
> index 0000000..028aba66d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
> @@ -0,0 +1,41 @@
> +* Texas Instruments tsc2007 touchscreen controller
> +
> +Required properties:
> +- compatible: must be "ti,tsc2007".
> +- reg: I2C address of the chip.
> +- ti,x-plate-ohms: X-plate resistance in ohms.
> +
> +Optional properties:
> +- gpios: the interrupt gpio the chip is connected to (trough the penirq pin).
nack use interrupt property this a non-sense that we do today to pass irq via
gpio property the should NEVER known it's a gpio just an irq
> +  The penirq pin goes to low when the panel is touched.
> +  (see GPIO binding[1] for more details).
> +- interrupt-parent: the phandle for the gpio controller
> +  (see interrupt binding[0]).
> +- interrupts: (gpio) interrupt to which the chip is connected
> +  (see interrupt binding[0]).
> +- ti,max-rt: maximum pressure.
> +- ti,fuzzx: specifies the absolute input fuzz x value.
> +  If set, it will permit noise in the data up to +- the value given to the fuzz
> +  parameter, that is used to filter noise from the event stream.
> +- ti,fuzzy: specifies the absolute input fuzz y value.
> +- ti,fuzzz: specifies the absolute input fuzz z value.
fuzz{x,y,z} look a weird name
> +- ti,poll-period: how much time to wait(in millisecond) before reading again the
> +  values from the tsc2007.
so put -ms in the binding to de clear and does not requiere to read the doc

Best Regards,
J.
> +
> +[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
> +[1]: Documentation/devicetree/bindings/gpio/gpio.txt
> +
> +Example:
> +	&i2c1 {
> +		/* ... */
> +		tsc2007@49 {
> +			compatible = "ti,tsc2007";
> +			reg = <0x49>;
> +			interrupt-parent = <&gpio4>;
> +			interrupts = <0x0 0x8>;
> +			gpios = <&gpio4 0 0>;
> +			ti,x-plate-ohms = <180>;
> +		};
> +
> +		/* ... */
> +	};
> diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
> index 0b67ba4..3168a99 100644
> --- a/drivers/input/touchscreen/tsc2007.c
> +++ b/drivers/input/touchscreen/tsc2007.c
> @@ -26,6 +26,9 @@
>  #include <linux/interrupt.h>
>  #include <linux/i2c.h>
>  #include <linux/i2c/tsc2007.h>
> +#include <linux/of_device.h>
> +#include <linux/of.h>
> +#include <linux/of_gpio.h>
>  
>  #define TSC2007_MEASURE_TEMP0		(0x0 << 4)
>  #define TSC2007_MEASURE_AUX		(0x2 << 4)
> @@ -74,7 +77,12 @@ struct tsc2007 {
>  	u16			max_rt;
>  	unsigned long		poll_delay;
>  	unsigned long		poll_period;
> +	int			fuzzx;
> +	int			fuzzy;
> +	int			fuzzz;
> +	char			of;
>  
> +	unsigned		gpio;
>  	int			irq;
>  
>  	wait_queue_head_t	wait;
> @@ -84,6 +92,11 @@ struct tsc2007 {
>  	void			(*clear_penirq)(void);
>  };
>  
> +static int tsc2007_get_pendown_state_dt(struct tsc2007 *ts)
> +{
> +	return !gpio_get_value(ts->gpio);
> +}
> +
>  static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
>  {
>  	s32 data;
> @@ -142,6 +155,14 @@ static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
>  	return rt;
>  }
>  
> +static bool tsc2007_is_pen_down_valid(struct tsc2007 *ts)
> +{
> +	if (ts->of)
> +		return gpio_is_valid(ts->gpio);
> +	else
> +		return ts->get_pendown_state ? true : false;
> +}
> +
>  static bool tsc2007_is_pen_down(struct tsc2007 *ts)
>  {
>  	/*
> @@ -158,10 +179,13 @@ static bool tsc2007_is_pen_down(struct tsc2007 *ts)
>  	 * to fall back on the pressure reading.
>  	 */
>  
> -	if (!ts->get_pendown_state)
> +	if (!tsc2007_is_pen_down_valid(ts))
>  		return true;
>  
> -	return ts->get_pendown_state();
> +	if (ts->of)
> +		return tsc2007_get_pendown_state_dt(ts);
> +	else
> +		return ts->get_pendown_state();
>  }
>  
>  static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
> @@ -178,7 +202,7 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
>  
>  		rt = tsc2007_calculate_pressure(ts, &tc);
>  
> -		if (rt == 0 && !ts->get_pendown_state) {
> +		if (!rt && !tsc2007_is_pen_down_valid(ts)) {
>  			/*
>  			 * If pressure reported is 0 and we don't have
>  			 * callback to check pendown state, we have to
> @@ -228,7 +252,7 @@ static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
>  {
>  	struct tsc2007 *ts = handle;
>  
> -	if (!ts->get_pendown_state || likely(ts->get_pendown_state()))
> +	if (tsc2007_is_pen_down(ts))
>  		return IRQ_WAKE_THREAD;
>  
>  	if (ts->clear_penirq)
> @@ -273,34 +297,71 @@ static void tsc2007_close(struct input_dev *input_dev)
>  	tsc2007_stop(ts);
>  }
>  
> -static int tsc2007_probe(struct i2c_client *client,
> -				   const struct i2c_device_id *id)
> +#ifdef CONFIG_OF
> +static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
> +			    struct device_node *np)
>  {
> -	struct tsc2007 *ts;
> -	struct tsc2007_platform_data *pdata = client->dev.platform_data;
> -	struct input_dev *input_dev;
> -	int err;
> -
> -	if (!pdata) {
> -		dev_err(&client->dev, "platform data is required!\n");
> +	int err = 0;
> +	u32 val32;
> +	u64 val64;
> +
> +	if (!of_property_read_u32(np, "ti,max-rt", &val32))
> +		ts->max_rt = val32;
> +	else
> +		ts->max_rt = MAX_12BIT;
> +
> +	if (!of_property_read_u32(np, "ti,fuzzx", &val32))
> +		ts->fuzzx = val32;
> +
> +	if (!of_property_read_u32(np, "ti,fuzzy", &val32))
> +		ts->fuzzy = val32;
> +
> +	if (!of_property_read_u32(np, "ti,fuzzz", &val32))
> +		ts->fuzzz = val32;
> +
> +	if (!of_property_read_u64(np, "ti,poll-period", &val64))
> +		ts->poll_period = val64;
> +	else
> +		ts->poll_period = 1;
> +
> +	if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
> +		ts->x_plate_ohms = val32;
> +	} else {
> +		dev_err(&client->dev,
> +			"Error: lacking ti,x-plate-ohms devicetree property. (err %d).",
> +			err);
>  		return -EINVAL;
>  	}
>  
> -	if (!i2c_check_functionality(client->adapter,
> -				     I2C_FUNC_SMBUS_READ_WORD_DATA))
> -		return -EIO;
> +	ts->gpio = of_get_gpio(np, 0);
> +	if (!gpio_is_valid(ts->gpio))
> +		dev_err(&client->dev,
> +			"GPIO not found (of_get_gpio returned %d)\n",
> +			ts->gpio);
>  
> -	ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
> -	input_dev = input_allocate_device();
> -	if (!ts || !input_dev) {
> -		err = -ENOMEM;
> -		goto err_free_mem;
> -	}
> +	/* Used to detect if it is probed trough the device tree,
> +	 * in order to be able to use that information in the IRQ handler.
> +	 */
> +	ts->of = 1;
>  
> -	ts->client = client;
> -	ts->irq = client->irq;
> -	ts->input = input_dev;
> -	init_waitqueue_head(&ts->wait);
> +	return 0;
> +}
> +#else
> +static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
> +			    struct device_node *np)
> +{
> +	return -ENODEV;
> +}
> +#endif
> +
> +static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
> +			      struct tsc2007_platform_data *pdata,
> +			      const struct i2c_device_id *id)
> +{
> +	if (!pdata) {
> +		dev_err(&client->dev, "platform data is required!\n");
> +		return -EINVAL;
> +	}
>  
>  	ts->model             = pdata->model;
>  	ts->x_plate_ohms      = pdata->x_plate_ohms;
> @@ -309,13 +370,59 @@ static int tsc2007_probe(struct i2c_client *client,
>  	ts->poll_period       = pdata->poll_period ? : 1;
>  	ts->get_pendown_state = pdata->get_pendown_state;
>  	ts->clear_penirq      = pdata->clear_penirq;
> +	ts->fuzzx             = pdata->fuzzx;
> +	ts->fuzzy             = pdata->fuzzy;
> +	ts->fuzzz             = pdata->fuzzz;
>  
>  	if (pdata->x_plate_ohms == 0) {
>  		dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
> -		err = -EINVAL;
> -		goto err_free_mem;
> +		return -EINVAL;
>  	}
>  
> +	/* Used to detect if it is probed trough the device tree,
> +	 * in order to be able to use that information in the IRQ handler.
> +	 */
> +	ts->of = 0;
> +
> +	return 0;
> +}
> +
> +static int tsc2007_probe(struct i2c_client *client,
> +			 const struct i2c_device_id *id)
> +{
> +	struct device_node *np = client->dev.of_node;
> +	struct tsc2007_platform_data *pdata = client->dev.platform_data;
> +	struct tsc2007 *ts;
> +	struct input_dev *input_dev;
> +	int err = 0;
> +
> +	ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
> +	if (!ts)
> +		return -ENOMEM;
> +
> +	if (np)
> +		err = tsc2007_probe_dt(client, ts, np);
> +	else
> +		err = tsc2007_probe_pdev(client, ts, pdata, id);
> +
> +	if (err)
> +		return err;
> +
> +	if (!i2c_check_functionality(client->adapter,
> +				     I2C_FUNC_SMBUS_READ_WORD_DATA))
> +		return -EIO;
> +
> +	input_dev = input_allocate_device();
> +	if (!input_dev) {
> +		err = -ENOMEM;
> +		goto err_free_input;
> +	};
> +
> +	ts->client = client;
> +	ts->irq = client->irq;
> +	ts->input = input_dev;
> +	init_waitqueue_head(&ts->wait);
> +
>  	snprintf(ts->phys, sizeof(ts->phys),
>  		 "%s/input0", dev_name(&client->dev));
>  
> @@ -331,19 +438,21 @@ static int tsc2007_probe(struct i2c_client *client,
>  	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, MAX_12BIT, pdata->fuzzx, 0);
> -	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, pdata->fuzzy, 0);
> +	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzx, 0);
> +	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
>  	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
> -			pdata->fuzzz, 0);
> +			     ts->fuzzz, 0);
>  
> -	if (pdata->init_platform_hw)
> -		pdata->init_platform_hw();
> +	if (!np) {
> +		if (pdata->init_platform_hw)
> +			pdata->init_platform_hw();
> +	}
>  
>  	err = request_threaded_irq(ts->irq, tsc2007_hard_irq, tsc2007_soft_irq,
>  				   IRQF_ONESHOT, client->dev.driver->name, ts);
>  	if (err < 0) {
>  		dev_err(&client->dev, "irq %d busy?\n", ts->irq);
> -		goto err_free_mem;
> +		goto err_free_input;
>  	}
>  
>  	tsc2007_stop(ts);
> @@ -358,23 +467,27 @@ static int tsc2007_probe(struct i2c_client *client,
>  
>   err_free_irq:
>  	free_irq(ts->irq, ts);
> -	if (pdata->exit_platform_hw)
> -		pdata->exit_platform_hw();
> - err_free_mem:
> +	if (!np) {
> +		if (pdata->exit_platform_hw)
> +			pdata->exit_platform_hw();
> +	}
> + err_free_input:
>  	input_free_device(input_dev);
> -	kfree(ts);
>  	return err;
>  }
>  
>  static int tsc2007_remove(struct i2c_client *client)
>  {
> +	struct device_node *np = client->dev.of_node;
>  	struct tsc2007	*ts = i2c_get_clientdata(client);
>  	struct tsc2007_platform_data *pdata = client->dev.platform_data;
>  
>  	free_irq(ts->irq, ts);
>  
> -	if (pdata->exit_platform_hw)
> -		pdata->exit_platform_hw();
> +	if (!np) {
> +		if (pdata->exit_platform_hw)
> +			pdata->exit_platform_hw();
> +	}
>  
>  	input_unregister_device(ts->input);
>  	kfree(ts);
> @@ -389,10 +502,19 @@ static const struct i2c_device_id tsc2007_idtable[] = {
>  
>  MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
>  
> +#ifdef CONFIG_OF
> +static const struct of_device_id tsc2007_of_match[] = {
> +	{ .compatible = "ti,tsc2007" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, tsc2007_of_match);
> +#endif
> +
>  static struct i2c_driver tsc2007_driver = {
>  	.driver = {
>  		.owner	= THIS_MODULE,
> -		.name	= "tsc2007"
> +		.name	= "tsc2007",
> +		.of_match_table = of_match_ptr(tsc2007_of_match),
>  	},
>  	.id_table	= tsc2007_idtable,
>  	.probe		= tsc2007_probe,
> -- 
> 1.7.9.5
>
Eric Bénard Nov. 21, 2013, 8:03 a.m. UTC | #2
Hi Jean Christophe,

Le Thu, 21 Nov 2013 06:05:44 +0100,
Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> a écrit :
> > +Optional properties:
> > +- gpios: the interrupt gpio the chip is connected to (trough the penirq pin).
> nack use interrupt property this a non-sense that we do today to pass irq via
> gpio property the should NEVER known it's a gpio just an irq

read previous email and you will see the GPIO is used to get the signal
level on the pin and not the IRQ.

Eric
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
new file mode 100644
index 0000000..028aba66d
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt
@@ -0,0 +1,41 @@ 
+* Texas Instruments tsc2007 touchscreen controller
+
+Required properties:
+- compatible: must be "ti,tsc2007".
+- reg: I2C address of the chip.
+- ti,x-plate-ohms: X-plate resistance in ohms.
+
+Optional properties:
+- gpios: the interrupt gpio the chip is connected to (trough the penirq pin).
+  The penirq pin goes to low when the panel is touched.
+  (see GPIO binding[1] for more details).
+- interrupt-parent: the phandle for the gpio controller
+  (see interrupt binding[0]).
+- interrupts: (gpio) interrupt to which the chip is connected
+  (see interrupt binding[0]).
+- ti,max-rt: maximum pressure.
+- ti,fuzzx: specifies the absolute input fuzz x value.
+  If set, it will permit noise in the data up to +- the value given to the fuzz
+  parameter, that is used to filter noise from the event stream.
+- ti,fuzzy: specifies the absolute input fuzz y value.
+- ti,fuzzz: specifies the absolute input fuzz z value.
+- ti,poll-period: how much time to wait(in millisecond) before reading again the
+  values from the tsc2007.
+
+[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+[1]: Documentation/devicetree/bindings/gpio/gpio.txt
+
+Example:
+	&i2c1 {
+		/* ... */
+		tsc2007@49 {
+			compatible = "ti,tsc2007";
+			reg = <0x49>;
+			interrupt-parent = <&gpio4>;
+			interrupts = <0x0 0x8>;
+			gpios = <&gpio4 0 0>;
+			ti,x-plate-ohms = <180>;
+		};
+
+		/* ... */
+	};
diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
index 0b67ba4..3168a99 100644
--- a/drivers/input/touchscreen/tsc2007.c
+++ b/drivers/input/touchscreen/tsc2007.c
@@ -26,6 +26,9 @@ 
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
 #include <linux/i2c/tsc2007.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 
 #define TSC2007_MEASURE_TEMP0		(0x0 << 4)
 #define TSC2007_MEASURE_AUX		(0x2 << 4)
@@ -74,7 +77,12 @@  struct tsc2007 {
 	u16			max_rt;
 	unsigned long		poll_delay;
 	unsigned long		poll_period;
+	int			fuzzx;
+	int			fuzzy;
+	int			fuzzz;
+	char			of;
 
+	unsigned		gpio;
 	int			irq;
 
 	wait_queue_head_t	wait;
@@ -84,6 +92,11 @@  struct tsc2007 {
 	void			(*clear_penirq)(void);
 };
 
+static int tsc2007_get_pendown_state_dt(struct tsc2007 *ts)
+{
+	return !gpio_get_value(ts->gpio);
+}
+
 static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
 {
 	s32 data;
@@ -142,6 +155,14 @@  static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
 	return rt;
 }
 
+static bool tsc2007_is_pen_down_valid(struct tsc2007 *ts)
+{
+	if (ts->of)
+		return gpio_is_valid(ts->gpio);
+	else
+		return ts->get_pendown_state ? true : false;
+}
+
 static bool tsc2007_is_pen_down(struct tsc2007 *ts)
 {
 	/*
@@ -158,10 +179,13 @@  static bool tsc2007_is_pen_down(struct tsc2007 *ts)
 	 * to fall back on the pressure reading.
 	 */
 
-	if (!ts->get_pendown_state)
+	if (!tsc2007_is_pen_down_valid(ts))
 		return true;
 
-	return ts->get_pendown_state();
+	if (ts->of)
+		return tsc2007_get_pendown_state_dt(ts);
+	else
+		return ts->get_pendown_state();
 }
 
 static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
@@ -178,7 +202,7 @@  static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
 
 		rt = tsc2007_calculate_pressure(ts, &tc);
 
-		if (rt == 0 && !ts->get_pendown_state) {
+		if (!rt && !tsc2007_is_pen_down_valid(ts)) {
 			/*
 			 * If pressure reported is 0 and we don't have
 			 * callback to check pendown state, we have to
@@ -228,7 +252,7 @@  static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
 {
 	struct tsc2007 *ts = handle;
 
-	if (!ts->get_pendown_state || likely(ts->get_pendown_state()))
+	if (tsc2007_is_pen_down(ts))
 		return IRQ_WAKE_THREAD;
 
 	if (ts->clear_penirq)
@@ -273,34 +297,71 @@  static void tsc2007_close(struct input_dev *input_dev)
 	tsc2007_stop(ts);
 }
 
-static int tsc2007_probe(struct i2c_client *client,
-				   const struct i2c_device_id *id)
+#ifdef CONFIG_OF
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
+			    struct device_node *np)
 {
-	struct tsc2007 *ts;
-	struct tsc2007_platform_data *pdata = client->dev.platform_data;
-	struct input_dev *input_dev;
-	int err;
-
-	if (!pdata) {
-		dev_err(&client->dev, "platform data is required!\n");
+	int err = 0;
+	u32 val32;
+	u64 val64;
+
+	if (!of_property_read_u32(np, "ti,max-rt", &val32))
+		ts->max_rt = val32;
+	else
+		ts->max_rt = MAX_12BIT;
+
+	if (!of_property_read_u32(np, "ti,fuzzx", &val32))
+		ts->fuzzx = val32;
+
+	if (!of_property_read_u32(np, "ti,fuzzy", &val32))
+		ts->fuzzy = val32;
+
+	if (!of_property_read_u32(np, "ti,fuzzz", &val32))
+		ts->fuzzz = val32;
+
+	if (!of_property_read_u64(np, "ti,poll-period", &val64))
+		ts->poll_period = val64;
+	else
+		ts->poll_period = 1;
+
+	if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
+		ts->x_plate_ohms = val32;
+	} else {
+		dev_err(&client->dev,
+			"Error: lacking ti,x-plate-ohms devicetree property. (err %d).",
+			err);
 		return -EINVAL;
 	}
 
-	if (!i2c_check_functionality(client->adapter,
-				     I2C_FUNC_SMBUS_READ_WORD_DATA))
-		return -EIO;
+	ts->gpio = of_get_gpio(np, 0);
+	if (!gpio_is_valid(ts->gpio))
+		dev_err(&client->dev,
+			"GPIO not found (of_get_gpio returned %d)\n",
+			ts->gpio);
 
-	ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
-	input_dev = input_allocate_device();
-	if (!ts || !input_dev) {
-		err = -ENOMEM;
-		goto err_free_mem;
-	}
+	/* Used to detect if it is probed trough the device tree,
+	 * in order to be able to use that information in the IRQ handler.
+	 */
+	ts->of = 1;
 
-	ts->client = client;
-	ts->irq = client->irq;
-	ts->input = input_dev;
-	init_waitqueue_head(&ts->wait);
+	return 0;
+}
+#else
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts,
+			    struct device_node *np)
+{
+	return -ENODEV;
+}
+#endif
+
+static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
+			      struct tsc2007_platform_data *pdata,
+			      const struct i2c_device_id *id)
+{
+	if (!pdata) {
+		dev_err(&client->dev, "platform data is required!\n");
+		return -EINVAL;
+	}
 
 	ts->model             = pdata->model;
 	ts->x_plate_ohms      = pdata->x_plate_ohms;
@@ -309,13 +370,59 @@  static int tsc2007_probe(struct i2c_client *client,
 	ts->poll_period       = pdata->poll_period ? : 1;
 	ts->get_pendown_state = pdata->get_pendown_state;
 	ts->clear_penirq      = pdata->clear_penirq;
+	ts->fuzzx             = pdata->fuzzx;
+	ts->fuzzy             = pdata->fuzzy;
+	ts->fuzzz             = pdata->fuzzz;
 
 	if (pdata->x_plate_ohms == 0) {
 		dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
-		err = -EINVAL;
-		goto err_free_mem;
+		return -EINVAL;
 	}
 
+	/* Used to detect if it is probed trough the device tree,
+	 * in order to be able to use that information in the IRQ handler.
+	 */
+	ts->of = 0;
+
+	return 0;
+}
+
+static int tsc2007_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct device_node *np = client->dev.of_node;
+	struct tsc2007_platform_data *pdata = client->dev.platform_data;
+	struct tsc2007 *ts;
+	struct input_dev *input_dev;
+	int err = 0;
+
+	ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	if (np)
+		err = tsc2007_probe_dt(client, ts, np);
+	else
+		err = tsc2007_probe_pdev(client, ts, pdata, id);
+
+	if (err)
+		return err;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_READ_WORD_DATA))
+		return -EIO;
+
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		err = -ENOMEM;
+		goto err_free_input;
+	};
+
+	ts->client = client;
+	ts->irq = client->irq;
+	ts->input = input_dev;
+	init_waitqueue_head(&ts->wait);
+
 	snprintf(ts->phys, sizeof(ts->phys),
 		 "%s/input0", dev_name(&client->dev));
 
@@ -331,19 +438,21 @@  static int tsc2007_probe(struct i2c_client *client,
 	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, MAX_12BIT, pdata->fuzzx, 0);
-	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, pdata->fuzzy, 0);
+	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzx, 0);
+	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
 	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
-			pdata->fuzzz, 0);
+			     ts->fuzzz, 0);
 
-	if (pdata->init_platform_hw)
-		pdata->init_platform_hw();
+	if (!np) {
+		if (pdata->init_platform_hw)
+			pdata->init_platform_hw();
+	}
 
 	err = request_threaded_irq(ts->irq, tsc2007_hard_irq, tsc2007_soft_irq,
 				   IRQF_ONESHOT, client->dev.driver->name, ts);
 	if (err < 0) {
 		dev_err(&client->dev, "irq %d busy?\n", ts->irq);
-		goto err_free_mem;
+		goto err_free_input;
 	}
 
 	tsc2007_stop(ts);
@@ -358,23 +467,27 @@  static int tsc2007_probe(struct i2c_client *client,
 
  err_free_irq:
 	free_irq(ts->irq, ts);
-	if (pdata->exit_platform_hw)
-		pdata->exit_platform_hw();
- err_free_mem:
+	if (!np) {
+		if (pdata->exit_platform_hw)
+			pdata->exit_platform_hw();
+	}
+ err_free_input:
 	input_free_device(input_dev);
-	kfree(ts);
 	return err;
 }
 
 static int tsc2007_remove(struct i2c_client *client)
 {
+	struct device_node *np = client->dev.of_node;
 	struct tsc2007	*ts = i2c_get_clientdata(client);
 	struct tsc2007_platform_data *pdata = client->dev.platform_data;
 
 	free_irq(ts->irq, ts);
 
-	if (pdata->exit_platform_hw)
-		pdata->exit_platform_hw();
+	if (!np) {
+		if (pdata->exit_platform_hw)
+			pdata->exit_platform_hw();
+	}
 
 	input_unregister_device(ts->input);
 	kfree(ts);
@@ -389,10 +502,19 @@  static const struct i2c_device_id tsc2007_idtable[] = {
 
 MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
 
+#ifdef CONFIG_OF
+static const struct of_device_id tsc2007_of_match[] = {
+	{ .compatible = "ti,tsc2007" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tsc2007_of_match);
+#endif
+
 static struct i2c_driver tsc2007_driver = {
 	.driver = {
 		.owner	= THIS_MODULE,
-		.name	= "tsc2007"
+		.name	= "tsc2007",
+		.of_match_table = of_match_ptr(tsc2007_of_match),
 	},
 	.id_table	= tsc2007_idtable,
 	.probe		= tsc2007_probe,