From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Takashi Iwai tiwai@suse.de
commit 7a46f05e5e163c00e41892e671294286e53fe15c upstream.
There seem devices that don't work with the aux channel backlight control. For allowing such users to test with the other backlight control method, provide a new module option, aux_backlight, to specify enabling or disabling the aux backport support explicitly. As default, the aux support is detected by the hardware capability.
v2: make the backlight option generic in case we add future backlight types (Alex)
BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1180749 BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1438 Reviewed-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 ++++ drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++++ 3 files changed, 10 insertions(+)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -179,6 +179,7 @@ extern uint amdgpu_smu_memory_pool_size; extern uint amdgpu_dc_feature_mask; extern uint amdgpu_dc_debug_mask; extern uint amdgpu_dm_abm_level; +extern int amdgpu_backlight; extern struct amdgpu_mgpu_info mgpu_info; extern int amdgpu_ras_enable; extern uint amdgpu_ras_mask; --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -777,6 +777,10 @@ uint amdgpu_dm_abm_level; MODULE_PARM_DESC(abmlevel, "ABM level (0 = off (default), 1-4 = backlight reduction level) "); module_param_named(abmlevel, amdgpu_dm_abm_level, uint, 0444);
+int amdgpu_backlight = -1; +MODULE_PARM_DESC(backlight, "Backlight control (0 = pwm, 1 = aux, -1 auto (default))"); +module_param_named(backlight, amdgpu_backlight, bint, 0444); + /** * DOC: tmz (int) * Trusted Memory Zone (TMZ) is a method to protect data being written --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2209,6 +2209,11 @@ static void update_connector_ext_caps(st caps->ext_caps->bits.hdr_aux_backlight_control == 1) caps->aux_support = true;
+ if (amdgpu_backlight == 0) + caps->aux_support = false; + else if (amdgpu_backlight == 1) + caps->aux_support = true; + /* From the specification (CTA-861-G), for calculating the maximum * luminance we need to use: * Luminance = 50*2**(CV/32)