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: NThomas Chou <thomas@wytron.com.tw>
Acked-by: NSimon Glass <sjg@chromium.org>

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

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

drivers/misc/misc-uclass.c

+/*
+ * 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",
+};

include/dm/uclass-id.h

@@ -39,6 +39,7 @@ enum uclass_id {
 	UCLASS_LED,		/* Light-emitting diode (LED) */
 	UCLASS_LPC,		/* x86 'low pin count' interface */
 	UCLASS_MASS_STORAGE,	/* Mass storage device */
+	UCLASS_MISC,		/* Miscellaneous device */
 	UCLASS_MMC,		/* SD / MMC card or chip */
 	UCLASS_MOD_EXP,		/* RSA Mod Exp device */
 	UCLASS_PCH,		/* x86 platform controller hub */

include/misc.h

+/*
+ * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _MISC_H_
+#define _MISC_H_
+
+/*
+ * Read the device to buffer, optional.
+ *
+ * @dev: the device
+ * @offset: offset to read the device
+ * @buf: pointer to data buffer
+ * @size: data size in bytes to read the device
+ * @return: 0 if OK, -ve on error
+ */
+int misc_read(struct udevice *dev, int offset, void *buf, int size);
+/*
+ * Write buffer to the device, optional.
+ *
+ * @dev: the device
+ * @offset: offset to write the device
+ * @buf: pointer to data buffer
+ * @size: data size in bytes to write the device
+ * @return: 0 if OK, -ve on error
+ */
+int misc_write(struct udevice *dev, int offset, void *buf, int size);
+/*
+ * Assert command to the device, optional.
+ *
+ * @dev: the device
+ * @request: command to be sent to the device
+ * @buf: pointer to buffer related to the requset
+ * @return: 0 if OK, -ve on error
+ */
+int misc_ioctl(struct udevice *dev, unsigned long request, void *buf);
+
+/*
+ * struct misc_ops - Driver model Misc operations
+ *
+ * The uclass interface is implemented by all miscellaneous devices which
+ * use driver model.
+ */
+struct misc_ops {
+	/*
+	 * Read the device to buffer, optional.
+	 *
+	 * @dev: the device
+	 * @offset: offset to read the device
+	 * @buf: pointer to data buffer
+	 * @size: data size in bytes to read the device
+	 * @return: 0 if OK, -ve on error
+	 */
+	int (*read)(struct udevice *dev, int offset, void *buf, int size);
+	/*
+	 * Write buffer to the device, optional.
+	 *
+	 * @dev: the device
+	 * @offset: offset to write the device
+	 * @buf: pointer to data buffer
+	 * @size: data size in bytes to write the device
+	 * @return: 0 if OK, -ve on error
+	 */
+	int (*write)(struct udevice *dev, int offset, const void *buf,
+		     int size);
+	/*
+	 * Assert command to the device, optional.
+	 *
+	 * @dev: the device
+	 * @request: command to be sent to the device
+	 * @buf: pointer to buffer related to the requset
+	 * @return: 0 if OK, -ve on error
+	 */
+	int (*ioctl)(struct udevice *dev, unsigned long request, void *buf);
+};
+
+#endif	/* _MISC_H_ */