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@xxxxxxxxx> --- drivers/acpi/video_detect.c | 3 +++ 1 file changed, 3 insertions(+) Index: linux-2.6/drivers/acpi/video_detect.c =================================================================== --- linux-2.6.orig/drivers/acpi/video_detect.c +++ linux-2.6/drivers/acpi/video_detect.c @@ -55,6 +55,9 @@ acpi_backlight_cap_match(acpi_handle han 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; } -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html