So far, DCS backlight driver hardcode (0xFF) for max brightness level. MIPI DCS spec allow max 0xFFFF for set_display_brightness (51h) command. And VBT brightness precision bits can support 8 ~ 16 bits.
We should set correct precision bits in VBT that meet panel's request. Driver can refer to this setting then configure max brightness level in DCS backlight driver properly. Cc: Ville Syrjala <[email protected]> Cc: Jani Nikula <[email protected]> Cc: Vandita Kulkarni <[email protected]> Cc: Cooper Chiou <[email protected]> Cc: William Tseng <[email protected]> Signed-off-by: Lee Shawn C <[email protected]> --- drivers/gpu/drm/i915/display/intel_bios.c | 3 +++ .../gpu/drm/i915/display/intel_dsi_dcs_backlight.c | 12 +++++++++--- drivers/gpu/drm/i915/i915_drv.h | 1 + 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index 5b6922e28ef2..a43cbf35a01d 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -483,6 +483,9 @@ parse_lfp_backlight(struct drm_i915_private *i915, level = 255; } i915->vbt.backlight.min_brightness = min_level; + + i915->vbt.backlight.max_brightness_level = + (1 << backlight_data->brightness_precision_bits[panel_type]) - 1; } else { level = backlight_data->level[panel_type]; i915->vbt.backlight.min_brightness = entry->min_brightness; diff --git a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c index 584c14c4cbd0..cd85520d36e2 100644 --- a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c @@ -41,7 +41,7 @@ #define POWER_SAVE_HIGH (3 << 0) #define POWER_SAVE_OUTDOOR_MODE (4 << 0) -#define PANEL_PWM_MAX_VALUE 0xFF +#define PANEL_PWM_MAX_VALUE 0xFFFF static u32 dcs_get_backlight(struct intel_connector *connector, enum pipe unused) { @@ -147,10 +147,16 @@ static void dcs_enable_backlight(const struct intel_crtc_state *crtc_state, static int dcs_setup_backlight(struct intel_connector *connector, enum pipe unused) { + struct drm_device *dev = connector->base.dev; + struct drm_i915_private *dev_priv = to_i915(dev); struct intel_panel *panel = &connector->panel; - panel->backlight.max = PANEL_PWM_MAX_VALUE; - panel->backlight.level = PANEL_PWM_MAX_VALUE; + panel->backlight.max = dev_priv->vbt.backlight.max_brightness_level \ + ? dev_priv->vbt.backlight.max_brightness_level \ + : PANEL_PWM_MAX_VALUE; + panel->backlight.level = dev_priv->vbt.backlight.max_brightness_level \ + ? dev_priv->vbt.backlight.max_brightness_level \ + : PANEL_PWM_MAX_VALUE; return 0; } diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index f99b6c0dd068..210eef301ba6 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -712,6 +712,7 @@ struct intel_vbt_data { struct { u16 pwm_freq_hz; + u16 max_brightness_level; bool present; bool active_low_pwm; u8 min_brightness; /* min_brightness/255 of max */ -- 2.17.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
