| Message ID | 20220818184302.10051-18-hdegoede@redhat.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | drm/kms: Stop registering multiple /sys/class/backlight devs for a single display | expand |
On 8/18/22 1:42 PM, Hans de Goede wrote: > On some new laptop designs a new Nvidia specific WMI interface is present > which gives info about panel brightness control and may allow controlling > the brightness through this interface when the embedded controller is used > for brightness control. > > When this WMI interface is present and indicates that the EC is used, > then this interface should be used for brightness control. > > Changes in v2: > - Use the new shared nvidia-wmi-ec-backlight.h header for the > WMI firmware API definitions > - ACPI_VIDEO can now be enabled on non X86 too, > adjust the Kconfig changes to match this. > > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > --- > drivers/acpi/Kconfig | 1 + > drivers/acpi/video_detect.c | 37 ++++++++++++++++++++++++++++++++++ > drivers/gpu/drm/gma500/Kconfig | 2 ++ > drivers/gpu/drm/i915/Kconfig | 2 ++ > include/acpi/video.h | 1 + > 5 files changed, 43 insertions(+) > > diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig > index 7802d8846a8d..44ad4b6bd234 100644 > --- a/drivers/acpi/Kconfig > +++ b/drivers/acpi/Kconfig > @@ -212,6 +212,7 @@ config ACPI_VIDEO > tristate "Video" > depends on BACKLIGHT_CLASS_DEVICE > depends on INPUT > + depends on ACPI_WMI || !X86 > select THERMAL > help > This driver implements the ACPI Extensions For Display Adapters > diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c > index cc9d0d91e268..1749e85d6921 100644 > --- a/drivers/acpi/video_detect.c > +++ b/drivers/acpi/video_detect.c > @@ -32,6 +32,7 @@ > #include <linux/dmi.h> > #include <linux/module.h> > #include <linux/pci.h> > +#include <linux/platform_data/x86/nvidia-wmi-ec-backlight.h> > #include <linux/types.h> > #include <linux/workqueue.h> > #include <acpi/video.h> > @@ -75,6 +76,36 @@ find_video(acpi_handle handle, u32 lvl, void *context, void **rv) > return AE_OK; > } > > +/* This depends on ACPI_WMI which is X86 only */ > +#ifdef CONFIG_X86 > +static bool nvidia_wmi_ec_supported(void) > +{ > + struct wmi_brightness_args args = { > + .mode = WMI_BRIGHTNESS_MODE_GET, > + .val = 0, > + .ret = 0, > + }; > + struct acpi_buffer buf = { (acpi_size)sizeof(args), &args }; > + acpi_status status; > + > + status = wmi_evaluate_method("603E9613-EF25-4338-A3D0-C46177516DB7", 0, I think it would be preferable for the GUID to be in the new shared header file as well. Apart from that, I think this change looks sane. > + WMI_BRIGHTNESS_METHOD_SOURCE, &buf, &buf); > + if (ACPI_FAILURE(status)) > + return false; > + > + /* > + * If brightness is handled by the EC then nvidia-wmi-ec-backlight > + * should be used, else the GPU driver(s) should be used. > + */ > + return args.ret == WMI_BRIGHTNESS_SOURCE_EC; > +} > +#else > +static bool nvidia_wmi_ec_supported(void) > +{ > + return false; > +} > +#endif > + > /* Force to use vendor driver when the ACPI device is known to be > * buggy */ > static int video_detect_force_vendor(const struct dmi_system_id *d) > @@ -541,6 +572,7 @@ static const struct dmi_system_id video_detect_dmi_table[] = { > static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) > { > static DEFINE_MUTEX(init_mutex); > + static bool nvidia_wmi_ec_present; > static bool native_available; > static bool init_done; > static long video_caps; > @@ -553,6 +585,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) > acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, > ACPI_UINT32_MAX, find_video, NULL, > &video_caps, NULL); > + nvidia_wmi_ec_present = nvidia_wmi_ec_supported(); > init_done = true; > } > if (native) > @@ -570,6 +603,10 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) > if (acpi_backlight_dmi != acpi_backlight_undef) > return acpi_backlight_dmi; > > + /* Special cases such as nvidia_wmi_ec and apple gmux. */ > + if (nvidia_wmi_ec_present) > + return acpi_backlight_nvidia_wmi_ec; > + > /* On systems with ACPI video use either native or ACPI video. */ > if (video_caps & ACPI_VIDEO_BACKLIGHT) { > /* > diff --git a/drivers/gpu/drm/gma500/Kconfig b/drivers/gpu/drm/gma500/Kconfig > index 0cff20265f97..807b989e3c77 100644 > --- a/drivers/gpu/drm/gma500/Kconfig > +++ b/drivers/gpu/drm/gma500/Kconfig > @@ -7,6 +7,8 @@ config DRM_GMA500 > select ACPI_VIDEO if ACPI > select BACKLIGHT_CLASS_DEVICE if ACPI > select INPUT if ACPI > + select X86_PLATFORM_DEVICES if ACPI > + select ACPI_WMI if ACPI > help > Say yes for an experimental 2D KMS framebuffer driver for the > Intel GMA500 (Poulsbo), Intel GMA600 (Moorestown/Oak Trail) and > diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig > index 7ae3b7d67fcf..3efce05d7b57 100644 > --- a/drivers/gpu/drm/i915/Kconfig > +++ b/drivers/gpu/drm/i915/Kconfig > @@ -23,6 +23,8 @@ config DRM_I915 > # but for select to work, need to select ACPI_VIDEO's dependencies, ick > select BACKLIGHT_CLASS_DEVICE if ACPI > select INPUT if ACPI > + select X86_PLATFORM_DEVICES if ACPI > + select ACPI_WMI if ACPI > select ACPI_VIDEO if ACPI > select ACPI_BUTTON if ACPI > select SYNC_FILE > diff --git a/include/acpi/video.h b/include/acpi/video.h > index 0625806d3bbd..91578e77ac4e 100644 > --- a/include/acpi/video.h > +++ b/include/acpi/video.h > @@ -48,6 +48,7 @@ enum acpi_backlight_type { > acpi_backlight_video, > acpi_backlight_vendor, > acpi_backlight_native, > + acpi_backlight_nvidia_wmi_ec, > }; > > #if IS_ENABLED(CONFIG_ACPI_VIDEO)
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 7802d8846a8d..44ad4b6bd234 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -212,6 +212,7 @@ config ACPI_VIDEO tristate "Video" depends on BACKLIGHT_CLASS_DEVICE depends on INPUT + depends on ACPI_WMI || !X86 select THERMAL help This driver implements the ACPI Extensions For Display Adapters diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index cc9d0d91e268..1749e85d6921 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -32,6 +32,7 @@ #include <linux/dmi.h> #include <linux/module.h> #include <linux/pci.h> +#include <linux/platform_data/x86/nvidia-wmi-ec-backlight.h> #include <linux/types.h> #include <linux/workqueue.h> #include <acpi/video.h> @@ -75,6 +76,36 @@ find_video(acpi_handle handle, u32 lvl, void *context, void **rv) return AE_OK; } +/* This depends on ACPI_WMI which is X86 only */ +#ifdef CONFIG_X86 +static bool nvidia_wmi_ec_supported(void) +{ + struct wmi_brightness_args args = { + .mode = WMI_BRIGHTNESS_MODE_GET, + .val = 0, + .ret = 0, + }; + struct acpi_buffer buf = { (acpi_size)sizeof(args), &args }; + acpi_status status; + + status = wmi_evaluate_method("603E9613-EF25-4338-A3D0-C46177516DB7", 0, + WMI_BRIGHTNESS_METHOD_SOURCE, &buf, &buf); + if (ACPI_FAILURE(status)) + return false; + + /* + * If brightness is handled by the EC then nvidia-wmi-ec-backlight + * should be used, else the GPU driver(s) should be used. + */ + return args.ret == WMI_BRIGHTNESS_SOURCE_EC; +} +#else +static bool nvidia_wmi_ec_supported(void) +{ + return false; +} +#endif + /* Force to use vendor driver when the ACPI device is known to be * buggy */ static int video_detect_force_vendor(const struct dmi_system_id *d) @@ -541,6 +572,7 @@ static const struct dmi_system_id video_detect_dmi_table[] = { static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) { static DEFINE_MUTEX(init_mutex); + static bool nvidia_wmi_ec_present; static bool native_available; static bool init_done; static long video_caps; @@ -553,6 +585,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, find_video, NULL, &video_caps, NULL); + nvidia_wmi_ec_present = nvidia_wmi_ec_supported(); init_done = true; } if (native) @@ -570,6 +603,10 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) if (acpi_backlight_dmi != acpi_backlight_undef) return acpi_backlight_dmi; + /* Special cases such as nvidia_wmi_ec and apple gmux. */ + if (nvidia_wmi_ec_present) + return acpi_backlight_nvidia_wmi_ec; + /* On systems with ACPI video use either native or ACPI video. */ if (video_caps & ACPI_VIDEO_BACKLIGHT) { /* diff --git a/drivers/gpu/drm/gma500/Kconfig b/drivers/gpu/drm/gma500/Kconfig index 0cff20265f97..807b989e3c77 100644 --- a/drivers/gpu/drm/gma500/Kconfig +++ b/drivers/gpu/drm/gma500/Kconfig @@ -7,6 +7,8 @@ config DRM_GMA500 select ACPI_VIDEO if ACPI select BACKLIGHT_CLASS_DEVICE if ACPI select INPUT if ACPI + select X86_PLATFORM_DEVICES if ACPI + select ACPI_WMI if ACPI help Say yes for an experimental 2D KMS framebuffer driver for the Intel GMA500 (Poulsbo), Intel GMA600 (Moorestown/Oak Trail) and diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 7ae3b7d67fcf..3efce05d7b57 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -23,6 +23,8 @@ config DRM_I915 # but for select to work, need to select ACPI_VIDEO's dependencies, ick select BACKLIGHT_CLASS_DEVICE if ACPI select INPUT if ACPI + select X86_PLATFORM_DEVICES if ACPI + select ACPI_WMI if ACPI select ACPI_VIDEO if ACPI select ACPI_BUTTON if ACPI select SYNC_FILE diff --git a/include/acpi/video.h b/include/acpi/video.h index 0625806d3bbd..91578e77ac4e 100644 --- a/include/acpi/video.h +++ b/include/acpi/video.h @@ -48,6 +48,7 @@ enum acpi_backlight_type { acpi_backlight_video, acpi_backlight_vendor, acpi_backlight_native, + acpi_backlight_nvidia_wmi_ec, }; #if IS_ENABLED(CONFIG_ACPI_VIDEO)