dm: input: Create a keyboard uclass

Add a uclass for keyboard input, mirroring the existing stdio methods.
This is enabled by a new CONFIG_DM_KEYBOARD option.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/input/Kconfig b/drivers/input/Kconfig
index bb00de7..447c4c3 100644
--- a/drivers/input/Kconfig
+++ b/drivers/input/Kconfig
@@ -1,3 +1,12 @@
+config DM_KEYBOARD
+	bool "Enable driver model keyboard support"
+	depends on DM
+	help
+	  This adds a uclass for keyboards and implements keyboard support
+	  using driver model. The API is implemented by keyboard.h and
+	  includes methods to start/stop the device, check for available
+	  input and update LEDs if the keyboard has them.
+
 config CROS_EC_KEYB
 	bool "Enable Chrome OS EC keyboard support"
 	help