Input: ili210x - add reset GPIO support

The touchscreen can have a reset GPIO connected to it, add support
for such an arrangement.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/ili210x.c b/drivers/input/touchscreen/ili210x.c
index 788f4140e302..f8b20d302384 100644
--- a/drivers/input/touchscreen/ili210x.c
+++ b/drivers/input/touchscreen/ili210x.c
@@ -6,6 +6,7 @@
 #include <linux/input/mt.h>
 #include <linux/delay.h>
 #include <linux/workqueue.h>
+#include <linux/gpio/consumer.h>
 
 #define MAX_TOUCHES             2
 #define DEFAULT_POLL_PERIOD     20
@@ -45,6 +46,7 @@ struct ili210x {
         struct input_dev *input;
         unsigned int poll_period;
         struct delayed_work dwork;
+        struct gpio_desc *reset_gpio;
 };
 
 static int ili210x_read_reg(struct i2c_client *client, u8 reg, void *buf,
@@ -168,11 +170,19 @@ static const struct attribute_group ili210x_attr_group = {
         .attrs = ili210x_attributes,
 };
 
+static void ili210x_power_down(void *data)
+{
+        struct gpio_desc *reset_gpio = data;
+
+        gpiod_set_value_cansleep(reset_gpio, 1);
+}
+
 static int ili210x_i2c_probe(struct i2c_client *client,
                                        const struct i2c_device_id *id)
 {
         struct device *dev = &client->dev;
         struct ili210x *priv;
+        struct gpio_desc *reset_gpio;
         struct input_dev *input;
         struct panel_info panel;
         struct firmware_version firmware;
@@ -186,6 +196,21 @@ static int ili210x_i2c_probe(struct i2c_client *client,
                 return -EINVAL;
         }
 
+        reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+        if (IS_ERR(reset_gpio))
+                return PTR_ERR(reset_gpio);
+
+        if (reset_gpio) {
+                error = devm_add_action_or_reset(dev, ili210x_power_down,
+                                                 reset_gpio);
+                if (error)
+                        return error;
+
+                usleep_range(50, 100);
+                gpiod_set_value_cansleep(reset_gpio, 0);
+                msleep(100);
+        }
+
         /* Get firmware version */
         error = ili210x_read_reg(client, REG_FIRMWARE_VERSION,
                                  &firmware, sizeof(firmware));
@@ -218,6 +243,7 @@ static int ili210x_i2c_probe(struct i2c_client *client,
         priv->input = input;
         priv->poll_period = DEFAULT_POLL_PERIOD;
         INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
+        priv->reset_gpio = reset_gpio;
 
         /* Setup input device */
         input->name = "ILI210x Touchscreen";