From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756560AbYJRTSk (ORCPT ); Sat, 18 Oct 2008 15:18:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751748AbYJRTFl (ORCPT ); Sat, 18 Oct 2008 15:05:41 -0400 Received: from mx2.suse.de ([195.135.220.15]:47791 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751591AbYJRTFj (ORCPT ); Sat, 18 Oct 2008 15:05:39 -0400 Date: Sat, 18 Oct 2008 11:48:21 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Zhao Yakui , linux-acpi@vger.kernel.org, Zhang Rui , Andi Kleen , Len Brown Subject: [patch 24/26] ACPI: Ignore _BQC object when registering backlight device Message-ID: <20081018184821.GY301@suse.de> References: <20081018183853.004667035@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="acpi-ignore-_bqc-object-when-registering-backlight-device.patch" In-Reply-To: <20081018184708.GA301@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.26-stable review patch. If anyone has any objections, please let us know. ------------------ From: Zhao Yakui upstream commmit: c2c789057f075022658b38b498755c29c1ba8055 According to acpi spec , the objectes of _BCL and _BCM are required if integrated LCD is present and supports brightness level and the _BQC is the optional object. So the _BQC object will be ignored when the backlight device is registered. At the same time when there is no _BQC object, the current brightness will be set to the maximum. http://bugzilla.kernel.org/show_bug.cgi?id=10206 Signed-off-by: Zhao Yakui Signed-off-by: Zhang Rui Signed-off-by: Andi Kleen Cc: Len Brown Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/video.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -720,7 +720,7 @@ static void acpi_video_device_find_cap(s kfree(obj); - if (device->cap._BCL && device->cap._BCM && device->cap._BQC && max_level > 0){ + if (device->cap._BCL && device->cap._BCM && max_level > 0) { int result; static int count = 0; char *name; @@ -732,7 +732,17 @@ static void acpi_video_device_find_cap(s device->backlight = backlight_device_register(name, NULL, device, &acpi_backlight_ops); device->backlight->props.max_brightness = device->brightness->count-3; - device->backlight->props.brightness = acpi_video_get_brightness(device->backlight); + /* + * If there exists the _BQC object, the _BQC object will be + * called to get the current backlight brightness. Otherwise + * the brightness will be set to the maximum. + */ + if (device->cap._BQC) + device->backlight->props.brightness = + acpi_video_get_brightness(device->backlight); + else + device->backlight->props.brightness = + device->backlight->props.max_brightness; backlight_update_status(device->backlight); kfree(name); --