: video output sysfs class and acpi video driver support

Hi,

This is a proposal for a unified sysfs interface to control video output device switch. The patch includes two parts:
1. output sysfs class. 2. acpi video driver support. Any comments are appreciated.

drivers/acpi/Kconfig +0 -0

 	  for integrated graphics devices on motherboard, as specified in

diff -BruN 2.6/drivers/acpi/video.c edited/drivers/acpi/video.c

drivers/acpi/video.c +2 -0

@@ -31,6 +31,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/backlight.h>
+#include <linux/output.h>
 
 #include <asm/uaccess.h>
 

@@ -163,6 +164,7 @@
 	struct acpi_video_bus *video;
 	struct acpi_device *dev;
 	struct acpi_video_device_brightness *brightness;
+	struct output_device *output_dev;
 };
 
 /* bus */

drivers/acpi/video.c +18 -0

 static struct backlight_device *acpi_video_backlight;
 static struct acpi_video_device *backlight_acpi_device;

@@ -275,6 +281,10 @@
 	.get_brightness = acpi_video_get_brightness,
 	.update_status  = acpi_video_set_brightness,
 };
+static struct output_properties acpi_output_properties = {
+	.set_state = acpi_video_output_set,
+	.get_status = acpi_video_output_get,
+};
 static int acpi_video_get_brightness(struct backlight_device *bd)
 {
 	unsigned long cur_level;

@@ -289,6 +299,20 @@
 	return 0;
 }
 
+static int acpi_video_output_get(struct output_device *od)
+{
+	unsigned long state;
+	struct acpi_video_device *vd = (struct acpi_video_device *)class_get_devdata(&od->class_dev);
+	acpi_video_device_get_state(vd, &state);
+	return (int)state;
+}
+
+static int acpi_video_output_set(struct output_device *od)
+{
+	unsigned long state = od->request_state;
+	struct acpi_video_device *vd = (struct acpi_video_device *)class_get_devdata(&od->class_dev);
+	return acpi_video_device_set_state(vd, state);
+}
 
 /* --------------------------------------------------------------------------
                                Video Management

drivers/acpi/video.c +4 -0

+		device->output_dev = video_output_register(name, device, &acpi_output_properties);
+	}
 	return;
 }
 

@@ -1617,6 +1648,8 @@
 	if (device == backlight_acpi_device)
 		backlight_device_unregister(acpi_video_backlight);
 
+	video_output_unregister(device->output_dev);
+
 	return 0;
 }
 

diff -BruN 2.6/drivers/video/Kconfig edited/drivers/video/Kconfig

drivers/video/Makefile +1 -0

 obj-$(CONFIG_FB_CFB_FILLRECT)  += cfbfillrect.o
 obj-$(CONFIG_FB_CFB_COPYAREA)  += cfbcopyarea.o

@@ -107,3 +107,4 @@
 
 # the test framebuffer is last
 obj-$(CONFIG_FB_VIRTUAL)          += vfb.o
+obj-$(CONFIG_VIDEO_OUTPUT_CONTROL) += output.o

diff -BruN 2.6/drivers/video/output.c edited/drivers/video/output.c

drivers/video/output.c +5 -0

@@ -0,0 +1,109 @@
+/*
+ * Video output switch support
+ */
+
+#include <linux/module.h>

drivers/video/output.c +20 -0

+		od->request_state = request_state;
+		od->props->set_state(od);
+	}
+	return count;
+} 
+
+static void video_output_class_release(struct class_device *dev)
+{
+        struct output_device *od = to_output_device(dev);
+        kfree(od);
+}
+
+static struct class_device_attribute video_output_attributes[] = {
+	__ATTR(state, 0644, video_output_show_state, video_output_store_state),
+	__ATTR_NULL,
+};
+
+static struct class video_output_class = {
+	.name = "video_output",
+	.release = video_output_class_release,

drivers/video/output.c +29 -0

+		goto error_return;
+	}
+	return new_dev;
+
+error_return:
+	return ERR_PTR(ret_code);
+}
+EXPORT_SYMBOL(video_output_register);
+
+void video_output_unregister(struct output_device *dev)
+{
+	if (!dev)
+		return;
+	class_device_unregister(&dev->class_dev);
+}
+EXPORT_SYMBOL(video_output_unregister);
+
+static void __exit video_output_class_exit(void)
+{
+	class_unregister(&video_output_class);
+}
+
+static int __init video_output_class_init(void)
+{
+	return class_register(&video_output_class);
+}
+
+postcore_initcall(video_output_class_init);
+module_exit(video_output_class_exit);

diff -BruN 2.6/include/linux/output.h edited/include/linux/output.h

include/linux/output.h +13 -0

@@ -0,0 +1,23 @@
+#ifndef _LINUX_OUTPUT_H
+#define _LINUX_OUTPUT_H
+
+#include <linux/device.h>
+
+struct output_device;
+
+struct output_properties {
+	int (*set_state)(struct output_device *);
+	int (*get_status)(struct output_device *);
+};
+
+struct output_device {