[PATCH 97/98] ACPI video: add a warning message if _BQC is not found

Len Brown
2009-03-28T04:33:58Z

From: Zhang Rui <rui.zhang@intel.com>

ACPI backlight control w/o _BQC support is kinda firmware bug.
Add a warning if _BQC is not implemented.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
---
drivers/acpi/video_detect.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index 50e3d2d..0973727 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -55,6 +55,9 @@ acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
"support\n"));
*cap |= ACPI_VIDEO_BACKLIGHT;
+ if (ACPI_FAILURE(acpi_get_handle(handle, "_BQC", &h_dummy)))
+ printk(KERN_WARNING FW_BUG PREFIX "ACPI brightness "
+ "control misses _BQC function\n");
/* We have backlight support, no need to scan further */
return AE_CTRL_TERMINATE;
}
--
1.6.0.6