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
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 8d0fc3c..7e76b12 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -5,6 +5,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-$(CONFIG_MISC) += misc-uclass.o
 obj-$(CONFIG_ALI152X) += ali512x.o
 obj-$(CONFIG_DS4510)  += ds4510.o
 obj-$(CONFIG_CBMEM_CONSOLE) += cbmem_console.o
diff --git a/drivers/misc/misc-uclass.c b/drivers/misc/misc-uclass.c
new file mode 100644
index 0000000..13a6ea5
--- /dev/null
+++ b/drivers/misc/misc-uclass.c
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <misc.h>
+
+/*
+ * Implement a  miscellaneous uclass 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.
+ */
+
+int misc_read(struct udevice *dev, int offset, void *buf, int size)
+{
+	const struct misc_ops *ops = device_get_ops(dev);
+
+	if (!ops->read)
+		return -ENOSYS;
+
+	return ops->read(dev, offset, buf, size);
+}
+
+int misc_write(struct udevice *dev, int offset, void *buf, int size)
+{
+	const struct misc_ops *ops = device_get_ops(dev);
+
+	if (!ops->write)
+		return -ENOSYS;
+
+	return ops->write(dev, offset, buf, size);
+}
+
+int misc_ioctl(struct udevice *dev, unsigned long request, void *buf)
+{
+	const struct misc_ops *ops = device_get_ops(dev);
+
+	if (!ops->ioctl)
+		return -ENOSYS;
+
+	return ops->ioctl(dev, request, buf);
+}
+
+UCLASS_DRIVER(misc) = {
+	.id		= UCLASS_MISC,
+	.name		= "misc",
+};