From b3c05aa9c8a94284dcb313df4de8fcd5821797f6 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Tue, 22 Feb 2022 17:40:39 +0100
Subject: drm/vc4: hdmi: Take the sink maximum TMDS clock into account
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Git-commit: 15a809211a6971cac5262c309aeadddc158c64d9
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

In the function that validates that the clock isn't too high, we've only
taken our controller limitations into account so far.

However, the sink can have a limit on the maximum TMDS clock it can deal
with too which is exposed through the EDID and the drm_display_info.

Make sure we check it.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220222164042.403112-5-maxime@cerno.tech
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 07871a3509ac..ca3fd4fb1c4f 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -1244,12 +1244,18 @@ static enum drm_mode_status
 vc4_hdmi_encoder_clock_valid(const struct vc4_hdmi *vc4_hdmi,
 			     unsigned long long clock)
 {
+	const struct drm_connector *connector = &vc4_hdmi->connector;
+	const struct drm_display_info *info = &connector->display_info;
+
 	if (clock > vc4_hdmi->variant->max_pixel_clock)
 		return MODE_CLOCK_HIGH;
 
 	if (vc4_hdmi->disable_4kp60 && clock > HDMI_14_MAX_TMDS_CLK)
 		return MODE_CLOCK_HIGH;
 
+	if (info->max_tmds_clock && clock > (info->max_tmds_clock * 1000))
+		return MODE_CLOCK_HIGH;
+
 	return MODE_OK;
 }
 
-- 
2.38.1