diff options
| author | Aaron Lu <aaron.lu@intel.com> | 2015-03-11 22:09:57 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-03-22 22:01:31 +0100 |
| commit | ff92cfe7cbc05c6c62f5b06c7d9090f4c853cd51 (patch) | |
| tree | 3ddeffe215c83867c5040bf7093442f0f922616e /drivers/acpi | |
| parent | 9eccca0843205f87c00404b663188b88eb248051 (diff) | |
| download | linux-ff92cfe7cbc05c6c62f5b06c7d9090f4c853cd51.tar.bz2 | |
ACPI / video: Allow forcing native backlight on non win8 machines
The native backlight behavior (so not registering both the acpi-video
and the vendor backlight driver) can be useful on some non win8 machines
too, so change the behavior of the video.use_native_backlight=1 or 0
kernel cmdline option to be: if user has set video.use_native_backlight=1
or 0, use that no matter if it is a win8 system or not. Also, we will
put some known systems into the DMI table to make them either use native
backlight interface or not, and the use_native_backlight_dmi is used to
reflect that.
Original-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/video.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index 26eb70c8f518..2f45dca31724 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -82,9 +82,15 @@ module_param(allow_duplicates, bool, 0644); * For Windows 8 systems: used to decide if video module * should skip registering backlight interface of its own. */ -static int use_native_backlight_param = -1; +enum { + NATIVE_BACKLIGHT_NOT_SET = -1, + NATIVE_BACKLIGHT_OFF, + NATIVE_BACKLIGHT_ON, +}; + +static int use_native_backlight_param = NATIVE_BACKLIGHT_NOT_SET; module_param_named(use_native_backlight, use_native_backlight_param, int, 0444); -static bool use_native_backlight_dmi = true; +static int use_native_backlight_dmi = NATIVE_BACKLIGHT_NOT_SET; static int register_count; static struct mutex video_list_lock; @@ -237,15 +243,16 @@ static void acpi_video_switch_brightness(struct work_struct *work); static bool acpi_video_use_native_backlight(void) { - if (use_native_backlight_param != -1) + if (use_native_backlight_param != NATIVE_BACKLIGHT_NOT_SET) return use_native_backlight_param; - else + else if (use_native_backlight_dmi != NATIVE_BACKLIGHT_NOT_SET) return use_native_backlight_dmi; + return acpi_osi_is_win8(); } bool acpi_video_verify_backlight_support(void) { - if (acpi_osi_is_win8() && acpi_video_use_native_backlight() && + if (acpi_video_use_native_backlight() && backlight_device_registered(BACKLIGHT_RAW)) return false; return acpi_video_backlight_support(); @@ -414,7 +421,7 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d) static int __init video_disable_native_backlight(const struct dmi_system_id *d) { - use_native_backlight_dmi = false; + use_native_backlight_dmi = NATIVE_BACKLIGHT_OFF; return 0; } |