From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: [PATCH] ACPI video: dmi check for broken _BQC on Acer Aspire 5720 Date: Fri, 24 Apr 2009 13:29:40 +0800 Message-ID: <1240550980.7661.544.camel@rzhang-dt> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from mga09.intel.com ([134.134.136.24]:46361 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752029AbZDXF32 (ORCPT ); Fri, 24 Apr 2009 01:29:28 -0400 Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Len Brown Cc: linux-acpi , "Zhang, Rui" , maximlevitsky@gmail.com On Acer Aspire 5720, _BQC always returns a value 9 smaller than the actual brightness level. Add dmi quirk for this laptop. http://bugzilla.kernel.org/show_bug.cgi?id=13121 Tested-by: Maxim Levitsky Signed-off-by: Zhang Rui --- drivers/acpi/video.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) Index: linux-2.6/drivers/acpi/video.c =================================================================== --- linux-2.6.orig/drivers/acpi/video.c +++ linux-2.6/drivers/acpi/video.c @@ -87,6 +87,8 @@ static const struct acpi_device_id video }; MODULE_DEVICE_TABLE(acpi, video_device_ids); +static int bqc_offset; + static struct acpi_driver acpi_video_bus = { .name = "video", .class = ACPI_VIDEO_CLASS, @@ -556,7 +558,8 @@ acpi_video_device_lcd_get_level_current( - 3 - (*level); *level = device->brightness->levels[*level + 2]; - } + } else if (bqc_offset) + *level += bqc_offset; device->brightness->curr = *level; return 0; } else { @@ -698,6 +701,29 @@ acpi_video_bus_DOS(struct acpi_video_bus return status; } +static int video_bqc_offset(const struct dmi_system_id *d) +{ + bqc_offset = 9; + return 0; +} + +static struct dmi_system_id video_dmi_table[] __initdata = { + /* + * Acer Aspire 5720 _BQC method is broken, + * it always returns a value smaller than the actual brightness level + * http://bugzilla.kernel.org/show_bug.cgi?id=13121 + */ + { + .callback = video_bqc_offset, + .ident = "Acer Aspire 5720", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "Acer"), + DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"), + }, + }, + {} +}; + /* * Simple comparison function used to sort backlight levels. */ @@ -2287,6 +2313,8 @@ EXPORT_SYMBOL(acpi_video_register); static int __init acpi_video_init(void) { + dmi_check_system(video_dmi_table); + if (intel_opregion_present()) return 0;