From: Jani Nikula <jani.nikula@intel.com>
To: Lee Shawn C <shawn.c.lee@intel.com>, intel-gfx@lists.freedesktop.org
Cc: ville.syrjala@linux.intel.com, vandita.kulkarni@intel.com,
cooper.chiou@intel.com, william.tseng@intel.com,
Lee Shawn C <shawn.c.lee@intel.com>
Subject: Re: [Intel-gfx] [v3 4/5] drm/i915/dsi: Retrieve max brightness level from VBT
Date: Wed, 08 Sep 2021 14:19:36 +0300 [thread overview]
Message-ID: <87pmtj5n7b.fsf@intel.com> (raw)
In-Reply-To: <20210902121429.27606-5-shawn.c.lee@intel.com>
On Thu, 02 Sep 2021, Lee Shawn C <shawn.c.lee@intel.com> wrote:
> 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.
>
> v2: modify variable name brightness_precision_bits instead of
> max_brightness_level.
> v3: fix checkpatch warning.
>
> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
> Cc: Cooper Chiou <cooper.chiou@intel.com>
> Cc: William Tseng <william.tseng@intel.com>
> Signed-off-by: Lee Shawn C <shawn.c.lee@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_bios.c | 3 +++
> drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c | 10 ++++++++--
> drivers/gpu/drm/i915/i915_drv.h | 1 +
> 3 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index e86e6ed2d3bf..ccaf0a3100f7 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.brightness_precision_bits =
> + backlight_data->brightness_precision_bits[panel_type];
> } 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..567c086602d5 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
> @@ -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;
> + if (dev_priv->vbt.backlight.brightness_precision_bits > 8)
> + panel->backlight.max = (1 << dev_priv->vbt.backlight.brightness_precision_bits) - 1;
> + else
> + panel->backlight.max = PANEL_PWM_MAX_VALUE;
> +
> + panel->backlight.level = panel->backlight.max;
>
> return 0;
> }
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index be2392bbcecc..99a2d308b24d 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -705,6 +705,7 @@ struct intel_vbt_data {
>
> struct {
> u16 pwm_freq_hz;
> + u16 brightness_precision_bits;
> bool present;
> bool active_low_pwm;
> u8 min_brightness; /* min_brightness/255 of max */
--
Jani Nikula, Intel Open Source Graphics Center
next prev parent reply other threads:[~2021-09-08 11:19 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-02 12:14 [Intel-gfx] [v3 0/5] DSI driver improvement Lee Shawn C
2021-09-02 12:14 ` [Intel-gfx] [v3 1/5] drm/i915/dsi: wait for header and payload credit available Lee Shawn C
2021-09-02 12:14 ` [Intel-gfx] [v3 2/5] drm/i915/dsi: refine send MIPI DCS command sequence Lee Shawn C
2021-09-02 12:14 ` [Intel-gfx] [v3 3/5] drm/i915: Get proper min cdclk if vDSC enabled Lee Shawn C
2021-09-08 11:29 ` Jani Nikula
2021-09-02 12:14 ` [Intel-gfx] [v3 4/5] drm/i915/dsi: Retrieve max brightness level from VBT Lee Shawn C
2021-09-08 11:19 ` Jani Nikula [this message]
2021-09-02 12:14 ` [Intel-gfx] [v3 5/5] drm/i915/dsi: Read/write proper brightness value via MIPI DCS command Lee Shawn C
2021-09-02 15:14 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for DSI driver improvement (rev3) Patchwork
2021-09-02 15:42 ` [Intel-gfx] ✓ Fi.CI.BAT: success " Patchwork
2021-09-02 19:21 ` [Intel-gfx] ✗ Fi.CI.IGT: failure " Patchwork
2021-09-08 13:51 ` Lee, Shawn C
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