Input: bu21013_ts - convert to use GPIO descriptors

This driver can use GPIO descriptors rather than GPIO numbers
without any problems, convert it. Name the field variables after
the actual pins on the chip rather than the "reset" and "touch"
names from the devicetree bindings that are vaguely inaccurate.

No in-tree users pass GPIO numbers in platform data so drop
this. Descriptor tables can be used to get these GPIOs from a board
file if need be.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/bu21013.txt

@@ -3,9 +3,10 @@
 Required properties:
  - compatible              : "rohm,bu21013_tp"
  - reg                     : I2C device address
+ - reset-gpios             : GPIO pin enabling (selecting) chip (CS)
 
 Optional properties:
- - touch-gpio              : GPIO pin registering a touch event
+ - touch-gpios             : GPIO pin registering a touch event
  - <supply_name>-supply    : Phandle to a regulator supply
  - rohm,touch-max-x        : Maximum outward permitted limit in the X axis
  - rohm,touch-max-y        : Maximum outward permitted limit in the Y axis

drivers/input/touchscreen/bu21013_ts.c

@@ -14,11 +14,9 @@
 #include <linux/slab.h>
 #include <linux/regulator/consumer.h>
 #include <linux/module.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 
-#define PEN_DOWN_INTR	0
 #define MAX_FINGERS	2
 #define RESET_DELAY	30
 #define PENUP_TIMEOUT	(10)
@@ -143,8 +141,9 @@
  * @touch_stopped: touch stop flag
  * @chip: pointer to the touch panel controller
  * @in_dev: pointer to the input device structure
- * @intr_pin: interrupt pin value
  * @regulator: pointer to the Regulator used for touch screen
+ * @cs_gpiod: chip select GPIO line
+ * @int_gpiod: touch interrupt GPIO line
  *
  * Touch panel device data structure
  */
@@ -154,8 +153,9 @@ struct bu21013_ts_data {
 	const struct bu21013_platform_device *chip;
 	struct input_dev *in_dev;
 	struct regulator *regulator;
+	struct gpio_desc *cs_gpiod;
+	struct gpio_desc *int_gpiod;
 	unsigned int irq;
-	unsigned int intr_pin;
 	bool touch_stopped;
 };
 
@@ -257,20 +257,21 @@ static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
 {
 	struct bu21013_ts_data *data = device_data;
 	struct i2c_client *i2c = data->client;
+	int keep_polling;
 	int retval;
 
 	do {
 		retval = bu21013_do_touch_report(data);
 		if (retval < 0) {
 			dev_err(&i2c->dev, "bu21013_do_touch_report failed\n");
-			return IRQ_NONE;
+			break;
 		}
 
-		data->intr_pin = gpio_get_value(data->chip->touch_pin);
-		if (data->intr_pin == PEN_DOWN_INTR)
+		keep_polling = gpiod_get_value(data->int_gpiod);
+		if (keep_polling)
 			wait_event_timeout(data->wait, data->touch_stopped,
 					   msecs_to_jiffies(2));
-	} while (!data->intr_pin && !data->touch_stopped);
+	} while (keep_polling && !data->touch_stopped);
 
 	return IRQ_HANDLED;
 }
@@ -425,28 +426,6 @@ static void bu21013_free_irq(struct bu21013_ts_data *bu21013_data)
 	free_irq(bu21013_data->irq, bu21013_data);
 }
 
-/**
- * bu21013_cs_disable() - deconfigures the touch panel controller
- * @bu21013_data: device structure pointer
- *
- * This function is used to deconfigure the chip selection
- * for touch panel controller.
- */
-static void bu21013_cs_disable(struct bu21013_ts_data *bu21013_data)
-{
-	int error;
-
-	error = gpio_direction_output(bu21013_data->chip->cs_pin, 0);
-	if (error < 0)
-		dev_warn(&bu21013_data->client->dev,
-			 "%s: gpio direction failed, error: %d\n",
-			 __func__, error);
-	else
-		gpio_set_value(bu21013_data->chip->cs_pin, 0);
-
-	gpio_free(bu21013_data->chip->cs_pin);
-}
-
 #ifdef CONFIG_OF
 static const struct bu21013_platform_device *
 bu21013_parse_dt(struct device *dev)
@@ -471,9 +450,6 @@ bu21013_parse_dt(struct device *dev)
 	of_property_read_u32(np, "rohm,touch-max-x", &pdata->touch_x_max);
 	of_property_read_u32(np, "rohm,touch-max-y", &pdata->touch_y_max);
 
-	pdata->touch_pin = of_get_named_gpio(np, "touch-gpio", 0);
-	pdata->cs_pin = of_get_named_gpio(np, "reset-gpio", 0);
-
 	pdata->ext_clk = false;
 
 	return pdata;
@@ -516,11 +492,6 @@ static int bu21013_probe(struct i2c_client *client,
 			return PTR_ERR(pdata);
 	}
 
-	if (!gpio_is_valid(pdata->touch_pin)) {
-		dev_err(&client->dev, "invalid touch_pin supplied\n");
-		return -EINVAL;
-	}
-
 	bu21013_data = kzalloc(sizeof(struct bu21013_ts_data), GFP_KERNEL);
 	in_dev = input_allocate_device();
 	if (!bu21013_data || !in_dev) {
@@ -529,16 +500,26 @@ static int bu21013_probe(struct i2c_client *client,
 		goto err_free_mem;
 	}
 
+	/* Named "INT" on the chip, DT binding is "touch" */
+	bu21013_data->int_gpiod = gpiod_get(&client->dev, "touch", GPIOD_IN);
+	error = PTR_ERR_OR_ZERO(bu21013_data->int_gpiod);
+	if (error) {
+		if (error != -EPROBE_DEFER)
+			dev_err(&client->dev, "failed to get INT GPIO\n");
+		goto err_free_mem;
+	}
+	gpiod_set_consumer_name(bu21013_data->int_gpiod, "BU21013 INT");
+
 	bu21013_data->in_dev = in_dev;
 	bu21013_data->chip = pdata;
 	bu21013_data->client = client;
-	bu21013_data->irq = gpio_to_irq(pdata->touch_pin);
+	bu21013_data->irq = gpiod_to_irq(bu21013_data->int_gpiod);
 
 	bu21013_data->regulator = regulator_get(&client->dev, "avdd");
 	if (IS_ERR(bu21013_data->regulator)) {
 		dev_err(&client->dev, "regulator_get failed\n");
 		error = PTR_ERR(bu21013_data->regulator);
-		goto err_free_mem;
+		goto err_put_int_gpio;
 	}
 
 	error = regulator_enable(bu21013_data->regulator);
@@ -550,13 +531,16 @@ static int bu21013_probe(struct i2c_client *client,
 	bu21013_data->touch_stopped = false;
 	init_waitqueue_head(&bu21013_data->wait);
 
-	/* configure the gpio pins */
-	error = gpio_request_one(pdata->cs_pin, GPIOF_OUT_INIT_HIGH,
-				 "touchp_reset");
-	if (error < 0) {
-		dev_err(&client->dev, "Unable to request gpio reset_pin\n");
+	/* Named "CS" on the chip, DT binding is "reset" */
+	bu21013_data->cs_gpiod = gpiod_get(&client->dev, "reset",
+					   GPIOD_OUT_HIGH);
+	error = PTR_ERR_OR_ZERO(bu21013_data->cs_gpiod);
+	if (error) {
+		if (error != -EPROBE_DEFER)
+			dev_err(&client->dev, "failed to get CS GPIO\n");
 		goto err_disable_regulator;
 	}
+	gpiod_set_consumer_name(bu21013_data->cs_gpiod, "BU21013 CS");
 
 	/* configure the touch panel controller */
 	error = bu21013_init_chip(bu21013_data);
@@ -604,11 +588,14 @@ static int bu21013_probe(struct i2c_client *client,
 err_free_irq:
 	bu21013_free_irq(bu21013_data);
 err_cs_disable:
-	bu21013_cs_disable(bu21013_data);
+	gpiod_set_value(bu21013_data->cs_gpiod, 0);
+	gpiod_put(bu21013_data->cs_gpiod);
 err_disable_regulator:
 	regulator_disable(bu21013_data->regulator);
 err_put_regulator:
 	regulator_put(bu21013_data->regulator);
+err_put_int_gpio:
+	gpiod_put(bu21013_data->int_gpiod);
 err_free_mem:
 	input_free_device(in_dev);
 	kfree(bu21013_data);
@@ -628,13 +615,16 @@ static int bu21013_remove(struct i2c_client *client)
 
 	bu21013_free_irq(bu21013_data);
 
-	bu21013_cs_disable(bu21013_data);
+	gpiod_set_value(bu21013_data->cs_gpiod, 0);
+	gpiod_put(bu21013_data->cs_gpiod);
 
 	input_unregister_device(bu21013_data->in_dev);
 
 	regulator_disable(bu21013_data->regulator);
 	regulator_put(bu21013_data->regulator);
 
+	gpiod_put(bu21013_data->int_gpiod);
+
 	kfree(bu21013_data);
 
 	return 0;

include/linux/input/bu21013.h

@@ -11,8 +11,6 @@
  * struct bu21013_platform_device - Handle the platform data
  * @touch_x_max: touch x max
  * @touch_y_max: touch y max
- * @cs_pin: chip select pin
- * @touch_pin: touch gpio pin
  * @ext_clk: external clock flag
  * @x_flip: x flip flag
  * @y_flip: y flip flag
@@ -23,8 +21,6 @@
 struct bu21013_platform_device {
 	int touch_x_max;
 	int touch_y_max;
-	unsigned int cs_pin;
-	unsigned int touch_pin;
 	bool ext_clk;
 	bool x_flip;
 	bool y_flip;