Input: tsc2007 - add device tree support.

Signed-off-by: Denis Carikli <denis@eukrea.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt

+* 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 milliseconds) 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>;
+		};
+
+		/* ... */
+	};

arch/arm/mach-imx/mach-cpuimx35.c

@@ -53,7 +53,7 @@ static const struct imxi2c_platform_data
 };
 
 #define TSC2007_IRQGPIO		IMX_GPIO_NR(3, 2)
-static int tsc2007_get_pendown_state(void)
+static int tsc2007_get_pendown_state(struct device *dev)
 {
 	return !gpio_get_value(TSC2007_IRQGPIO);
 }

arch/arm/mach-imx/mach-cpuimx51sd.c

@@ -121,7 +121,7 @@ static const struct imxuart_platform_data uart_pdata __initconst = {
 	.flags = IMXUART_HAVE_RTSCTS,
 };
 
-static int tsc2007_get_pendown_state(void)
+static int tsc2007_get_pendown_state(struct device *dev)
 {
 	if (mx51_revision() < IMX_CHIP_REVISION_3_0)
 		return !gpio_get_value(TSC2007_IRQGPIO_REV2);

arch/sh/boards/mach-ecovec24/setup.c

@@ -501,7 +501,7 @@ static struct platform_device keysc_device = {
 /* TouchScreen */
 #define IRQ0 evt2irq(0x600)
 
-static int ts_get_pendown_state(void)
+static int ts_get_pendown_state(struct device *dev)
 {
 	int val = 0;
 	gpio_free(GPIO_FN_INTC_IRQ0);

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)
@@ -74,13 +77,17 @@ struct tsc2007 {
 	u16			max_rt;
 	unsigned long		poll_delay;
 	unsigned long		poll_period;
+	int			fuzzx;
+	int			fuzzy;
+	int			fuzzz;
 
+	unsigned		gpio;
 	int			irq;
 
 	wait_queue_head_t	wait;
 	bool			stopped;
 
-	int			(*get_pendown_state)(void);
+	int			(*get_pendown_state)(struct device *);
 	void			(*clear_penirq)(void);
 };
 
@@ -161,7 +168,7 @@ static bool tsc2007_is_pen_down(struct tsc2007 *ts)
 	if (!ts->get_pendown_state)
 		return true;
 
-	return ts->get_pendown_state();
+	return ts->get_pendown_state(&ts->client->dev);
 }
 
 static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
@@ -178,7 +185,7 @@ 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 && !ts->get_pendown_state) {
 			/*
 			 * If pressure reported is 0 and we don't have
 			 * callback to check pendown state, we have to
@@ -228,7 +235,7 @@ 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)
@@ -273,35 +280,74 @@ 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_get_pendown_state_gpio(struct device *dev)
 {
-	struct tsc2007 *ts;
-	struct tsc2007_platform_data *pdata = client->dev.platform_data;
-	struct input_dev *input_dev;
-	int err;
+	struct i2c_client *client = to_i2c_client(dev);
+	struct tsc2007 *ts = i2c_get_clientdata(client);
+
+	return !gpio_get_value(ts->gpio);
+}
+
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
+{
+	struct device_node *np = client->dev.of_node;
+	u32 val32;
+	u64 val64;
 
-	if (!pdata) {
-		dev_err(&client->dev, "platform data is required!\n");
+	if (!np) {
+		dev_err(&client->dev, "missing device tree data\n");
 		return -EINVAL;
 	}
 
-	if (!i2c_check_functionality(client->adapter,
-				     I2C_FUNC_SMBUS_READ_WORD_DATA))
-		return -EIO;
+	if (!of_property_read_u32(np, "ti,max-rt", &val32))
+		ts->max_rt = val32;
+	else
+		ts->max_rt = MAX_12BIT;
 
-	ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
-	input_dev = input_allocate_device();
-	if (!ts || !input_dev) {
-		err = -ENOMEM;
-		goto err_free_mem;
+	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, "missing ti,x-plate-ohms devicetree property.");
+		return -EINVAL;
 	}
 
-	ts->client = client;
-	ts->irq = client->irq;
-	ts->input = input_dev;
-	init_waitqueue_head(&ts->wait);
+	ts->gpio = of_get_gpio(np, 0);
+	if (gpio_is_valid(ts->gpio))
+		ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
+	else
+		dev_warn(&client->dev,
+			 "GPIO not specified in DT (of_get_gpio returned %d)\n",
+			 ts->gpio);
 
+	return 0;
+}
+#else
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
+{
+	dev_err(&client->dev, "platform data is required!\n");
+	return -EINVAL;
+}
+#endif
+
+static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
+			      const struct tsc2007_platform_data *pdata,
+			      const struct i2c_device_id *id)
+{
 	ts->model             = pdata->model;
 	ts->x_plate_ohms      = pdata->x_plate_ohms;
 	ts->max_rt            = pdata->max_rt ? : MAX_12BIT;
@@ -309,13 +355,54 @@ 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;
 	}
 
+	return 0;
+}
+
+static int tsc2007_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct tsc2007 *ts;
+	struct input_dev *input_dev;
+	int err;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_READ_WORD_DATA))
+		return -EIO;
+
+	ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	if (pdata)
+		err = tsc2007_probe_pdev(client, ts, pdata, id);
+	else
+		err = tsc2007_probe_dt(client, ts);
+	if (err)
+		return err;
+
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		err = -ENOMEM;
+		goto err_free_input;
+	};
+
+	i2c_set_clientdata(client, ts);
+
+	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 +418,19 @@ 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)
+	if (pdata && 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);
@@ -352,28 +439,25 @@ static int tsc2007_probe(struct i2c_client *client,
 	if (err)
 		goto err_free_irq;
 
-	i2c_set_clientdata(client, ts);
-
 	return 0;
 
  err_free_irq:
 	free_irq(ts->irq, ts);
-	if (pdata->exit_platform_hw)
+	if (pdata && pdata->exit_platform_hw)
 		pdata->exit_platform_hw();
- err_free_mem:
+ err_free_input:
 	input_free_device(input_dev);
-	kfree(ts);
 	return err;
 }
 
 static int tsc2007_remove(struct i2c_client *client)
 {
-	struct tsc2007	*ts = i2c_get_clientdata(client);
-	struct tsc2007_platform_data *pdata = client->dev.platform_data;
+	const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct tsc2007 *ts = i2c_get_clientdata(client);
 
 	free_irq(ts->irq, ts);
 
-	if (pdata->exit_platform_hw)
+	if (pdata && pdata->exit_platform_hw)
 		pdata->exit_platform_hw();
 
 	input_unregister_device(ts->input);
@@ -389,10 +473,19 @@ 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,

include/linux/i2c/tsc2007.h

@@ -14,9 +14,9 @@ struct tsc2007_platform_data {
 	int	fuzzy;
 	int	fuzzz;
 
-	int	(*get_pendown_state)(void);
-	void	(*clear_penirq)(void);		/* If needed, clear 2nd level
-						   interrupt source */
+	int	(*get_pendown_state)(struct device *);
+	/* If needed, clear 2nd level interrupt source */
+	void	(*clear_penirq)(void);
 	int	(*init_platform_hw)(void);
 	void	(*exit_platform_hw)(void);
 };