On Friday, October 11, 2013 09:27:42 PM Aaron Lu wrote: > v5: > 1 Introduce video.use_native_backlight module parameter and set its > value to false by default as suggested by Rafael. For Win8 systems > which have broken ACPI video backlight control, the parameter can be > set to 1 in kernel cmdline to skip registering ACPI video's backlight > interface. Due to this change, the acpi_video_verify_backlight_support > is moved from video_detect.c to video.c - patch 3/4; > 2 Rename bd_list_head and bd_list_mutex in backlight.c to > backlight_dev_list and backlight_dev_list_mutex as suggested by Rafael > - patch 1/4. > > v4: > Remove decleration and stub for acpi_video_unregister_backlight in > video.h of patch 2/4 since that function doesn't exist anymore in v3. > > v3: > 1 Add a new patch 4/4 to fix some problems in thinkpad-acpi module; > 2 Remove unnecessary function acpi_video_unregister_backlight introduced > in patch 2/4 as pointed out by Jani Nikula. > > v2: > v1 has the subject of "Rework ACPI video driver" and is posted here: > http://lkml.org/lkml/2013/9/9/74 > Since the objective is really to fix Win8 backlight issues, I changed > the subject in this version, sorry about that. > > This patchset has four patches, the first introduced a new API named > backlight_device_registered in backlight layer that can be used for > backlight interface provider module to check if a specific type backlight > interface has been registered, see changelog for patch 1/4 for details. > Then patch 2/4 does the cleanup to sepeate the backlight control and > event delivery functionality in the ACPI video module and patch 3/4 > solves some Win8 backlight control problems by avoiding register ACPI > video's backlight interface if: > 1 Kernel cmdline option acpi_backlight=video is not given; > 2 This is a Win8 system; > 3 Native backlight control interface exists. > Patch 4/4 fixes some problems in thinkpad-acpi module. > > Technically, patch 2/4 is not required to fix the issue here. So if you > think it is not necessary, I can remove it from the series. > > Aaron Lu (4): > backlight: introduce backlight_device_registered > ACPI / video: seperate backlight control and event interface > ACPI / video: Do not register backlight if win8 and native interface > exists > thinkpad-acpi: fix handle locate for video and query of _BCL > > drivers/acpi/internal.h | 4 +- > drivers/acpi/video.c | 457 ++++++++++++++++++++--------------- > drivers/acpi/video_detect.c | 4 +- > drivers/platform/x86/thinkpad_acpi.c | 31 ++- > drivers/video/backlight/backlight.c | 31 +++ > include/linux/backlight.h | 4 + > 6 files changed, 326 insertions(+), 205 deletions(-) I've added this series to my queue for 3.13. Since the next step will be to introduce a list of systems that need video.use_native_backlight=1 *and* don't break in that configuration, I don't see much point adding another Kconfig option for the default. Hopefully, in the future we'll be able to fix the problems causing video.use_native_backlight=1 to fail of the systems where it fails and then we'll be able to make that the default behavior and drop the option altogether. Thanks! -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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