[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 <dsankou...@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