dm: implement a Miscellaneous uclass

Implement a Miscellaneous uclass with generic read or
write operations. This class is used only for those
do not fit other more general classes.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 8b38a84..031b4d8 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -4,6 +4,15 @@
 
 menu "Multifunction device drivers"
 
+config MISC
+	bool "Enable Driver Model for Misc drivers"
+	depends on DM
+	help
+	  Enable driver model for miscellaneous devices. This class is
+	  used only for those do not fit other more general classes. A
+	  set of generic read, write and ioctl methods may be used to
+	  access the device.
+
 config CMD_CROS_EC
 	bool "Enable crosec command"
 	depends on CROS_EC