On Thu, Apr 04, 2024 at 08:59:30AM +0530, Suraj Kandpal wrote:
> Write panel override luminance values which helps the TCON decide
> if tone mapping needs to be enabled or not.
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> ---
> .../drm/i915/display/intel_dp_aux_backlight.c | 25 +++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> index 7af876e2d210..20dd5a6a0f3f 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> @@ -381,6 +381,29 @@ static const char *dpcd_vs_pwm_str(bool aux)
> return aux ? "DPCD" : "PWM";
> }
>
> +static void
> +intel_dp_aux_write_panel_luminance_override(struct intel_connector *connector)
> +{
> + struct drm_i915_private *i915 = to_i915(connector->base.dev);
> + struct intel_panel *panel = &connector->panel;
> + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
> + int ret;
> + u8 buf[4] = {};
> +
> + buf[0] = panel->backlight.min & 0xFF;
> + buf[1] = (panel->backlight.min & 0xFF00) >> 8;
> + buf[2] = panel->backlight.max & 0xFF;
> + buf[3] = (panel->backlight.max & 0xFF00) >> 8;
> +
> + ret = drm_dp_dpcd_write(&intel_dp->aux,
> + INTEL_EDP_HDR_PANEL_LUMINANCE_OVERRIDE,
> + buf, sizeof(buf));
> + if (ret < 0)
> + drm_dbg_kms(&i915->drm,
> + "Panel Luminance DPCD reg write failed, err:-%d\n",
> + ret);
> +}
> +
> static int
> intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pipe)
> {
> @@ -412,6 +435,8 @@ intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pi
> panel->backlight.min = 0;
> }
>
> + intel_dp_aux_write_panel_luminance_override(connector);
> +
Should this really always be set? It says override. Doesn't the TCON
have some values already that we're overriding?
> drm_dbg_kms(&i915->drm, "[CONNECTOR:%d:%s] Using AUX HDR interface for backlight control (range %d..%d)\n",
> connector->base.base.id, connector->base.name,
> panel->backlight.min, panel->backlight.max);
