Subject: [PATCH] [acpi video] Add ability to enable/disable video bus

- Add set_int() helper to execute a method and set 1 integer
- Add run_dos() with bios_flag and lcd_flag parameter, as
  interface to the _DOS method for the device
- Add video_bus_{enable,disable}() that call run_dos() with
  the right parameters.
- Add ->v_dos to struct acpi_video_bus, and defines for
  encoding it.

Signed-off-by: Patrick Mochel <mochel@linux.intel.com>

---

 drivers/acpi/drivers/video/bus-device.c |   67 +++++++++++++++++++++++++++++++
 drivers/acpi/drivers/video/video.h      |   13 ++++++
 2 files changed, 80 insertions(+), 0 deletions(-)

applies-to: 84b0f9b6f2a0e1820e489912f9717946d3b41572
d8416a078fe8af8643b7309e79d328ab84466049
diff --git a/drivers/acpi/drivers/video/bus-device.c b/drivers/acpi/drivers/video/bus-device.c
index a9f7cb8..724ad07 100644
--- a/drivers/acpi/drivers/video/bus-device.c
+++ b/drivers/acpi/drivers/video/bus-device.c
@@ -40,6 +40,26 @@ static int get_int(struct acpi_dev * ad,
 }
 
 
+static int set_int(struct acpi_dev * ad, char * obj, u32 value)
+{
+	acpi_status status;
+	union acpi_object arg = {
+		.type		= ACPI_TYPE_INTEGER,
+		.integer	= {
+			.value	= value,
+		},
+	};
+	struct acpi_object_list arg_list = {
+		.count		= 1,
+		.pointer	= &arg,
+	};
+
+	status = acpi_evaluate_object(ad->acpi_device->handle, 
+				      "_DOS", &arg_list, NULL);
+	return ACPI_SUCCESS(status) ? 0 : -ENODEV;
+}
+
+
 /**
  *	can_switch - Check if a video bus supports video switching
  *	@ad:	The ACPI device representing the video bus
@@ -223,3 +243,50 @@ int video_bus_init(struct acpi_video_bus
 
 	return ret;
 }
+
+
+/**
+ *	run_dos - Set the video mode by executing _DOS
+ *	@vb:		The ACPI video bus
+ *	@bios_flag:	Determines how the switch of active display should happen
+ *	@lcd_flag:	Determines who controls LCD brightness on AC/DC power change
+ *
+ *	Possible values for @bios_flag are:
+ *
+ *	%VIDEO_DOS_BIOS_NO_AUTO		Don't let the BIOS do it automatically
+ *	%VIDEO_DOS_BIOS_AUTO		BIOS can automatically switch output
+ *	%VIDEO_DOS_BIOS_DGS_LOCK	The _DGS value should be locked (meaning?)
+ *	%VIDEO_DOS_BIOS_EVENT		Don't auto switch, but raise event
+ *
+ *	Possible values for @lcd_flag are:
+ *	%VIDEO_DOS_LCD_AUTO		BIOS should control brightness level
+ *	%VIDEO_DOS_LCD_NO_AUTO		BIOS should *not* control 
+ */
+
+static int run_dos(struct acpi_video_bus * vb, u32 bios_flag, u32 lcd_flag)
+{
+	u32 value = (lcd_flag << 2) | bios_flag;
+	int ret = 0;
+
+	if (vb->v_can_switch) {
+		ret = set_int(vb->v_ad, "_DOS", value);
+		if (!ret)
+			vb->v_dos = value;
+	}
+	return ret;
+}
+
+
+int video_bus_enable(struct acpi_video_bus * vb)
+{
+	int ret;
+
+	return run_dos(vb, VIDEO_DOS_BIOS_AUTO, VIDEO_DOS_LCD_AUTO);
+}
+
+int video_bus_disable(struct acpi_video_bus * vb)
+{
+	int ret;
+
+	return run_dos(vb, VIDEO_DOS_BIOS_NO_AUTO, VIDEO_DOS_LCD_NO_AUTO);
+}
diff --git a/drivers/acpi/drivers/video/video.h b/drivers/acpi/drivers/video/video.h
index a2988f3..9db2b55 100644
--- a/drivers/acpi/drivers/video/video.h
+++ b/drivers/acpi/drivers/video/video.h
@@ -16,6 +16,15 @@ ACPI_MODULE_NAME("acpi_video");
 #define ACPI_VIDEO_BUS_POST_PCI		0x02
 #define ACPI_VIDEO_BUS_POST_AGP		0x04
 
+#define VIDEO_DOS_BIOS_NO_AUTO	0x00
+#define VIDEO_DOS_BIOS_AUTO	0x01
+#define VIDEO_DOS_BIOS_DGS_LOCK	0x02
+#define VIDEO_DOS_BIOS_EVENT	0x03
+
+#define VIDEO_DOS_LCD_AUTO	0x00
+#define VIDEO_DOS_LCD_NO_AUTO	0x01
+
+
 struct acpi_video_bus {
 	int			v_can_switch;
 	int			v_has_rom;
@@ -24,9 +33,13 @@ struct acpi_video_bus {
 	int			v_post_options;
 	int			v_post_id;
 
+	u32			v_dos;
+
 	struct acpi_dev		* v_ad;
 };
 
 extern int video_bus_test(struct acpi_dev * ad);
 
 extern int video_bus_init(struct acpi_video_bus * vb);
+extern int video_bus_enable(struct acpi_video_bus * vb);
+extern int video_bus_disable(struct acpi_video_bus * vb);
---
0.99.9.GIT