From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aaron Lu Subject: Re: [PATCH] drm/i915/opregion: ignore firmware requests for backlight change Date: Fri, 27 Jun 2014 11:20:15 +0800 Message-ID: <53ACE2EF.8020808@intel.com> References: <53A8E400.5060709@intel.com> <87tx796yc5.fsf@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id 56EC37206E for ; Thu, 26 Jun 2014 20:23:09 -0700 (PDT) In-Reply-To: <87tx796yc5.fsf@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Jani Nikula , Igor Gnatenko , Anton Gubarkov Cc: Daniel Vetter , "intel-gfx@lists.freedesktop.org" , "Rafael J. Wysocki" , ACPI Devel Mailing List List-Id: intel-gfx@lists.freedesktop.org On 06/25/2014 07:08 PM, Jani Nikula wrote: > On Tue, 24 Jun 2014, Aaron Lu 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. Igor, Anton, Are you using legacy boot or UEFI boot? Possible to test the other case? > > One comment inline, otherwise Will add that in next revision. > > Acked-by: Jani Nikula Thanks for the review! -Aaron > > 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 >> Reported-and-tested-by: Anton Gubarkov >> Signed-off-by: Aaron Lu >> --- >> 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 >> >