ACPI video: if no ACPI backlight support, use vendor drivers
If an ACPI graphics device supports backlight brightness functions (cmp. with
latest ACPI spec Appendix B), let the ACPI video driver control backlight and
switch backlight control off in vendor specific ACPI drivers (asus_acpi,
thinkpad_acpi, eeepc, fujitsu_laptop, msi_laptop, sony_laptop, acer-wmi).
Currently it is possible to load above drivers and let both poke on the
brightness HW registers, the video and vendor specific ACPI drivers -> bad.
This patch provides the basic support to check for BIOS capabilities before
driver loading time. Driver specific modifications are in separate follow up
patches.
"acpi_backlight=vendor"
Prever vendor driver over ACPI driver for backlight.
"acpi_backlight=video" (default)
Prever ACPI driver over vendor driver for backlight.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index fd6a452..7f23761 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -194,6 +194,50 @@
#endif /* CONFIG_ACPI_WMI */
+#define ACPI_VIDEO_OUTPUT_SWITCHING 0x0001
+#define ACPI_VIDEO_DEVICE_POSTING 0x0002
+#define ACPI_VIDEO_ROM_AVAILABLE 0x0004
+#define ACPI_VIDEO_BACKLIGHT 0x0008
+#define ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR 0x0010
+#define ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO 0x0020
+#define ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VENDOR 0x0040
+#define ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO 0x0080
+#define ACPI_VIDEO_BACKLIGHT_DMI_VENDOR 0x0100
+#define ACPI_VIDEO_BACKLIGHT_DMI_VIDEO 0x0200
+#define ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VENDOR 0x0400
+#define ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VIDEO 0x0800
+
+#if defined(CONFIG_ACPI_VIDEO) || defined(CONFIG_ACPI_VIDEO_MODULE)
+
+extern long acpi_video_get_capabilities(acpi_handle graphics_dev_handle);
+extern long acpi_is_video_device(struct acpi_device *device);
+extern int acpi_video_backlight_support(void);
+extern int acpi_video_display_switch_support(void);
+
+#else
+
+static inline long acpi_video_get_capabilities(acpi_handle graphics_dev_handle)
+{
+ return 0;
+}
+
+static inline long acpi_is_video_device(struct acpi_device *device)
+{
+ return 0;
+}
+
+static inline int acpi_video_backlight_support(void)
+{
+ return 0;
+}
+
+static inline int acpi_video_display_switch_support(void)
+{
+ return 0;
+}
+
+#endif /* defined(CONFIG_ACPI_VIDEO) || defined(CONFIG_ACPI_VIDEO_MODULE) */
+
extern int acpi_blacklisted(void);
#ifdef CONFIG_DMI
extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d);