From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: [RESEND PATCH 7/7] ACPI : add a warning message if _BQC is not found Date: Thu, 12 Mar 2009 16:57:11 +0800 Message-ID: <1236848231.2807.76.camel@rzhang-dt> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from mga03.intel.com ([143.182.124.21]:63602 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754193AbZCLI4P (ORCPT ); Thu, 12 Mar 2009 04:56:15 -0400 Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Len Brown Cc: linux-acpi , Matthew Garrett , Thomas Renninger , "Zhang, Rui" ACPI backlight control w/o _BQC support is kinda firmware bug. Add a warning if _BQC is not implemented. Signed-off-by: Zhang Rui --- 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; }