[PATCH 2/3] dm: button: add support for linux_code in button-gpio.c driver

[Dzmitry Sankouski]

Linux event code may be used in input devices, using buttons.

Signed-off-by: Dzmitry Sankouski <dsankouski at gmail.com>
---
 drivers/button/button-gpio.c   | 20 ++++++++++++++++++++
 drivers/button/button-uclass.c | 10 ++++++++++
 include/button.h               | 16 ++++++++++++++++
 3 files changed, 46 insertions(+)

diff --git a/drivers/button/button-gpio.c b/drivers/button/button-gpio.c
index dbb000622c..e6eff5c1da 100644
--- a/drivers/button/button-gpio.c
+++ b/drivers/button/button-gpio.c
@@ -13,6 +13,7 @@
 
 struct button_gpio_priv {
 	struct gpio_desc gpio;
+	u32 linux_code;
 };
 
 static enum button_state_t button_gpio_get_state(struct udevice *dev)
@@ -29,10 +30,22 @@ static enum button_state_t button_gpio_get_state(struct udevice *dev)
 	return ret ? BUTTON_ON : BUTTON_OFF;
 }
 
+static u32 button_gpio_get_code(struct udevice *dev)
+{
+	struct button_gpio_priv *priv = dev_get_priv(dev);
+	u32 code = priv->linux_code;
+
+	if (!code)
+		return 0;
+
+	return code;
+}
+
 static int button_gpio_probe(struct udevice *dev)
 {
 	struct button_uc_plat *uc_plat = dev_get_uclass_plat(dev);
 	struct button_gpio_priv *priv = dev_get_priv(dev);
+	u32 linux_code;
 	int ret;
 
 	/* Ignore the top-level button node */
@@ -43,6 +56,12 @@ static int button_gpio_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
+	linux_code = dev_read_u32_default(dev, "linux,code", -ENODATA);
+	debug("linux code value: %d, ret: %d", linux_code, ret);
+	if (ret)
+		return ret;
+	priv->linux_code = linux_code;
+
 	return 0;
 }
 
@@ -92,6 +111,7 @@ static int button_gpio_bind(struct udevice *parent)
 
 static const struct button_ops button_gpio_ops = {
 	.get_state	= button_gpio_get_state,
+	.get_code	= button_gpio_get_code,
 };
 
 static const struct udevice_id button_gpio_ids[] = {
diff --git a/drivers/button/button-uclass.c b/drivers/button/button-uclass.c
index e33ed7d01d..6d0c6f69c5 100644
--- a/drivers/button/button-uclass.c
+++ b/drivers/button/button-uclass.c
@@ -38,6 +38,16 @@ enum button_state_t button_get_state(struct udevice *dev)
 	return ops->get_state(dev);
 }
 
+u32 button_get_code(struct udevice *dev)
+{
+	struct button_ops *ops = button_get_ops(dev);
+
+	if (!ops->get_code)
+		return -ENOSYS;
+
+	return ops->get_code(dev);
+}
+
 UCLASS_DRIVER(button) = {
 	.id		= UCLASS_BUTTON,
 	.name		= "button",
diff --git a/include/button.h b/include/button.h
index 96e6b1901f..27af4a6a1a 100644
--- a/include/button.h
+++ b/include/button.h
@@ -37,6 +37,14 @@ struct button_ops {
 	 * @return button state button_state_t, or -ve on error
 	 */
 	enum button_state_t (*get_state)(struct udevice *dev);
+
+	/**
+	 * get_code() - get linux event code of a button
+	 *
+	 * @dev:	button device to change
+	 * @return button code, or -ve on error
+	 */
+	u32 (*get_code)(struct udevice *dev);
 };
 
 #define button_get_ops(dev)	((struct button_ops *)(dev)->driver->ops)
@@ -58,4 +66,12 @@ int button_get_by_label(const char *label, struct udevice **devp);
  */
 enum button_state_t button_get_state(struct udevice *dev);
 
+/**
+ * button_get_code() - get linux event code of a button
+ *
+ * @dev:	button device to change
+ * @return button code, or -ve on error
+ */
+u32 button_get_code(struct udevice *dev);
+
 #endif
-- 
2.30.2