target/linux/bcm27xx/patches-5.15/950-0632-drm-vc4-hdmi-Take-the-sink-maximum-TMDS-clock-into-a.patch

   1 From e63d40712a11de18ea217c2211dfd3ae937bab7f Mon Sep 17 00:00:00 2001
   2 From: Maxime Ripard <maxime@cerno.tech>
   3 Date: Mon, 13 Dec 2021 15:33:11 +0100
   4 Subject: [PATCH] drm/vc4: hdmi: Take the sink maximum TMDS clock into
   5  account
   6
   7 In the function that validates that the clock isn't too high, we've only
   8 taken our controller limitations into account so far.
   9
  10 However, the sink can have a limit on the maximum TMDS clock it can deal
  11 with too which is exposed through the EDID and the drm_display_info.
  12
  13 Make sure we check it.
  14
  15 Signed-off-by: Maxime Ripard <maxime@cerno.tech>
  16 ---
  17  drivers/gpu/drm/vc4/vc4_hdmi.c | 6 ++++++
  18  1 file changed, 6 insertions(+)
  19
  20 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
  21 +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
  22 @@ -1256,12 +1256,18 @@ static enum drm_mode_status
  23  vc4_hdmi_encoder_clock_valid(const struct vc4_hdmi *vc4_hdmi,
  24                              unsigned long long clock)
  25  {
  26 +       const struct drm_connector *connector = &vc4_hdmi->connector;
  27 +       const struct drm_display_info *info = &connector->display_info;
  28 +
  29         if (clock > vc4_hdmi->variant->max_pixel_clock)
  30                 return MODE_CLOCK_HIGH;
  31
  32         if (vc4_hdmi->disable_4kp60 && clock > HDMI_14_MAX_TMDS_CLK)
  33                 return MODE_CLOCK_HIGH;
  34
  35 +       if (info->max_tmds_clock && clock > (info->max_tmds_clock * 1000))
  36 +               return MODE_CLOCK_HIGH;
  37 +
  38         return MODE_OK;
  39  }
  40