On Tue, 24 Jun 2014, Aaron Lu <aaron.lu@xxxxxxxxx> wrote: > Some Thinkpad laptops' firmware will initiate a backlight level change > request through operation region on the events of AC plug/unplug, but > since we are not using firmware's interface to do the backlight setting > on these affected laptops, we do not want the firmware to use some > arbitrary value from its ASL variable to set the backlight level on > AC plug/unplug either. I'm curious whether this happens with EFI boot, or only with legacy. One comment inline, otherwise Acked-by: Jani Nikula <jani.nikula@xxxxxxxxx> for merging through the ACPI tree, as the change is more likely to conflict there. > Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=76491 > Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=77091 > Reported-and-tested-by: Igor Gnatenko <i.gnatenko.brain@xxxxxxxxx> > Reported-and-tested-by: Anton Gubarkov <anton.gubarkov@xxxxxxxxx> > Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> > --- > drivers/acpi/video.c | 3 ++- > drivers/gpu/drm/i915/intel_opregion.c | 7 +++++++ > include/acpi/video.h | 2 ++ > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c > index fb9ffe9adc64..cf99d6d2d491 100644 > --- a/drivers/acpi/video.c > +++ b/drivers/acpi/video.c > @@ -241,13 +241,14 @@ static bool acpi_video_use_native_backlight(void) > return use_native_backlight_dmi; > } > > -static bool acpi_video_verify_backlight_support(void) > +bool acpi_video_verify_backlight_support(void) > { > if (acpi_osi_is_win8() && acpi_video_use_native_backlight() && > backlight_device_registered(BACKLIGHT_RAW)) > return false; > return acpi_video_backlight_support(); > } > +EXPORT_SYMBOL(acpi_video_verify_backlight_support); > > /* backlight device sysfs support */ > static int acpi_video_get_brightness(struct backlight_device *bd) > diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c > index 2e2c71fcc9ed..02943d93e88e 100644 > --- a/drivers/gpu/drm/i915/intel_opregion.c > +++ b/drivers/gpu/drm/i915/intel_opregion.c > @@ -403,6 +403,13 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp) > > DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp); > > + /* > + * If the acpi_video interface is not supposed to be used, don't > + * bother processing backlight level change requests from firmware. > + */ > + if (!acpi_video_verify_backlight_support()) > + return 0; I'd appreciate a DRM_DEBUG_KMS here about what happened. We're bound to wonder about that staring at some dmesg later on! > + > if (!(bclp & ASLE_BCLP_VALID)) > return ASLC_BACKLIGHT_FAILED; > > diff --git a/include/acpi/video.h b/include/acpi/video.h > index ea4c7bbded4d..92f8c4bffefb 100644 > --- a/include/acpi/video.h > +++ b/include/acpi/video.h > @@ -22,6 +22,7 @@ extern void acpi_video_unregister(void); > extern void acpi_video_unregister_backlight(void); > extern int acpi_video_get_edid(struct acpi_device *device, int type, > int device_id, void **edid); > +extern bool acpi_video_verify_backlight_support(void); > #else > static inline int acpi_video_register(void) { return 0; } > static inline void acpi_video_unregister(void) { return; } > @@ -31,6 +32,7 @@ static inline int acpi_video_get_edid(struct acpi_device *device, int type, > { > return -ENODEV; > } > +static bool acpi_video_verify_backlight_support() { return false; } > #endif > > #endif > -- > 1.9.3 > -- Jani Nikula, 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
