From 98758faffc86ee6fe9504eeab75481ee7c1aa860 Mon Sep 17 00:00:00 2001 From: Zhang Rui Date: Thu, 12 Mar 2009 16:57:11 +0800 Subject: [PATCH] ACPI video: add a warning message if _BQC is not found ACPI backlight control w/o _BQC support is kinda firmware bug. Add a warning if _BQC is not implemented. Signed-off-by: Zhang Rui Signed-off-by: Len Brown --- drivers/acpi/video_detect.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 50e3d2dbf3a..09737275e25 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; } -- 2.41.1