Message ID | 20231017175728.1.Ibc6408a8ff1f334974104c5bcc25f2f35a57f36e@changeid (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | drm/i915/quirk: Add quirk for devices with incorrect PWM frequency | expand |
Hi Allen, On Tue, Oct 17, 2023 at 06:01:39PM +0000, Allen Ballway wrote: > Cyernet T10C has a bad default PWM frequency causing the display to > strobe when the brightness is less than 100%. Create a new quirk to use > the value from the BIOS rather than the default register value. > > Signed-off-by: Allen Ballway <ballway@chromium.org> > > --- > > .../gpu/drm/i915/display/intel_backlight.c | 3 ++- > drivers/gpu/drm/i915/display/intel_quirks.c | 26 +++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_quirks.h | 1 + > 3 files changed, 29 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c > index 2e8f17c045222..c4dcfece9deca 100644 > --- a/drivers/gpu/drm/i915/display/intel_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_backlight.c > @@ -1388,7 +1388,8 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe > ctl = intel_de_read(i915, VLV_BLC_PWM_CTL(pipe)); > panel->backlight.pwm_level_max = ctl >> 16; > > - if (!panel->backlight.pwm_level_max) > + if (!panel->backlight.pwm_level_max || > + intel_has_quirk(i915, QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY)) > panel->backlight.pwm_level_max = get_backlight_max_vbt(connector); I think it would be better if we did: if (!intel_has_quirk(i915, QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY)) { ctl = intel_de_read(i915, VLV_BLC_PWM_CTL(pipe)); panel->backlight.pwm_level_max = ctl >> 16; } else { panel->backlight.pwm_level_max = 0; } if (!panel->backlight.pwm_level_max) panel->backlight.pwm_level_max = get_backlight_max_vbt(connector); The "else" branch can potentially be omitted if we know that backlight member is initialized to 0 (I suspect it is). > > if (!panel->backlight.pwm_level_max) > diff --git a/drivers/gpu/drm/i915/display/intel_quirks.c b/drivers/gpu/drm/i915/display/intel_quirks.c > index a280448df771a..ff6cb499428ce 100644 > --- a/drivers/gpu/drm/i915/display/intel_quirks.c > +++ b/drivers/gpu/drm/i915/display/intel_quirks.c > @@ -65,6 +65,12 @@ static void quirk_no_pps_backlight_power_hook(struct drm_i915_private *i915) > drm_info(&i915->drm, "Applying no pps backlight power quirk\n"); > } > > +static void quirk_ignore_default_pwm_frequency(struct drm_i915_private *i915) > +{ > + intel_set_quirk(i915, QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY); > + drm_info(&i915->drm, "Applying ignore default pwm frequency quirk"); > +} > + > struct intel_quirk { > int device; > int subsystem_vendor; > @@ -90,6 +96,12 @@ static int intel_dmi_no_pps_backlight(const struct dmi_system_id *id) > return 1; > } > > +static int intel_dmi_ignore_default_pwm_frequency(const struct dmi_system_id *id) > +{ > + DRM_INFO("Default PWM frequency is incorrect and is overridden on %s\n", id->ident); > + return 1; > +} > + > static const struct intel_dmi_quirk intel_dmi_quirks[] = { > { > .dmi_id_list = &(const struct dmi_system_id[]) { > @@ -136,6 +148,20 @@ static const struct intel_dmi_quirk intel_dmi_quirks[] = { > }, > .hook = quirk_no_pps_backlight_power_hook, > }, > + { > + .dmi_id_list = &(const struct dmi_system_id[]) { > + { > + .callback = intel_dmi_ignore_default_pwm_frequency, > + .ident = "Cybernet T10C Tablet", > + .matches = {DMI_EXACT_MATCH(DMI_BOARD_VENDOR, > + "Cybernet Manufacturing Inc."), > + DMI_EXACT_MATCH(DMI_BOARD_NAME, "T10C Tablet"), > + }, > + }, > + { } > + }, > + .hook = quirk_ignore_default_pwm_frequency, > + }, > }; > > static struct intel_quirk intel_quirks[] = { > diff --git a/drivers/gpu/drm/i915/display/intel_quirks.h b/drivers/gpu/drm/i915/display/intel_quirks.h > index 10a4d163149fd..70589505e5a0e 100644 > --- a/drivers/gpu/drm/i915/display/intel_quirks.h > +++ b/drivers/gpu/drm/i915/display/intel_quirks.h > @@ -17,6 +17,7 @@ enum intel_quirk_id { > QUIRK_INVERT_BRIGHTNESS, > QUIRK_LVDS_SSC_DISABLE, > QUIRK_NO_PPS_BACKLIGHT_POWER_HOOK, > + QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY You want a trailing comma here. > }; > > void intel_init_quirks(struct drm_i915_private *i915); > -- > 2.42.0.655.g421f12c284-goog > Thanks.
diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c index 2e8f17c045222..c4dcfece9deca 100644 --- a/drivers/gpu/drm/i915/display/intel_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_backlight.c @@ -1388,7 +1388,8 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe ctl = intel_de_read(i915, VLV_BLC_PWM_CTL(pipe)); panel->backlight.pwm_level_max = ctl >> 16; - if (!panel->backlight.pwm_level_max) + if (!panel->backlight.pwm_level_max || + intel_has_quirk(i915, QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY)) panel->backlight.pwm_level_max = get_backlight_max_vbt(connector); if (!panel->backlight.pwm_level_max) diff --git a/drivers/gpu/drm/i915/display/intel_quirks.c b/drivers/gpu/drm/i915/display/intel_quirks.c index a280448df771a..ff6cb499428ce 100644 --- a/drivers/gpu/drm/i915/display/intel_quirks.c +++ b/drivers/gpu/drm/i915/display/intel_quirks.c @@ -65,6 +65,12 @@ static void quirk_no_pps_backlight_power_hook(struct drm_i915_private *i915) drm_info(&i915->drm, "Applying no pps backlight power quirk\n"); } +static void quirk_ignore_default_pwm_frequency(struct drm_i915_private *i915) +{ + intel_set_quirk(i915, QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY); + drm_info(&i915->drm, "Applying ignore default pwm frequency quirk"); +} + struct intel_quirk { int device; int subsystem_vendor; @@ -90,6 +96,12 @@ static int intel_dmi_no_pps_backlight(const struct dmi_system_id *id) return 1; } +static int intel_dmi_ignore_default_pwm_frequency(const struct dmi_system_id *id) +{ + DRM_INFO("Default PWM frequency is incorrect and is overridden on %s\n", id->ident); + return 1; +} + static const struct intel_dmi_quirk intel_dmi_quirks[] = { { .dmi_id_list = &(const struct dmi_system_id[]) { @@ -136,6 +148,20 @@ static const struct intel_dmi_quirk intel_dmi_quirks[] = { }, .hook = quirk_no_pps_backlight_power_hook, }, + { + .dmi_id_list = &(const struct dmi_system_id[]) { + { + .callback = intel_dmi_ignore_default_pwm_frequency, + .ident = "Cybernet T10C Tablet", + .matches = {DMI_EXACT_MATCH(DMI_BOARD_VENDOR, + "Cybernet Manufacturing Inc."), + DMI_EXACT_MATCH(DMI_BOARD_NAME, "T10C Tablet"), + }, + }, + { } + }, + .hook = quirk_ignore_default_pwm_frequency, + }, }; static struct intel_quirk intel_quirks[] = { diff --git a/drivers/gpu/drm/i915/display/intel_quirks.h b/drivers/gpu/drm/i915/display/intel_quirks.h index 10a4d163149fd..70589505e5a0e 100644 --- a/drivers/gpu/drm/i915/display/intel_quirks.h +++ b/drivers/gpu/drm/i915/display/intel_quirks.h @@ -17,6 +17,7 @@ enum intel_quirk_id { QUIRK_INVERT_BRIGHTNESS, QUIRK_LVDS_SSC_DISABLE, QUIRK_NO_PPS_BACKLIGHT_POWER_HOOK, + QUIRK_IGNORE_DEFAULT_PWM_FREQUENCY }; void intel_init_quirks(struct drm_i915_private *i915);
Cyernet T10C has a bad default PWM frequency causing the display to strobe when the brightness is less than 100%. Create a new quirk to use the value from the BIOS rather than the default register value. Signed-off-by: Allen Ballway <ballway@chromium.org> --- .../gpu/drm/i915/display/intel_backlight.c | 3 ++- drivers/gpu/drm/i915/display/intel_quirks.c | 26 +++++++++++++++++++ drivers/gpu/drm/i915/display/intel_quirks.h | 1 + 3 files changed, 29 insertions(+), 1 deletion(-) -- 2.42.0.655.g421f12c284-goog