From: Lee Shawn C <shawn.c.lee@intel.com>
Date: Mon, 1 Sep 2025 05:57:20 +0000 (+0000)
Subject: drm/i915/hdmi: add debugfs to contorl HDMI bpc
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=51bfda2e7690805fab08453c8b057de224724fc0;p=users%2Fhch%2Fmisc.git

drm/i915/hdmi: add debugfs to contorl HDMI bpc

While performing HDMI compliance testing, test equipment may request
different bpc output for signal measurement. However, display driver
typically determines the maximum available bpc based on HW bandwidth.
This change leverages the existing debugfs (intel_force_link_bpp)
to manage HDMI bpc, and making it easier to pass HDMI CTS.

v2: Using exist variable max_requested_bpc.
v3: Extend intel_force_link_bpp to support HDMI as suggested by Imre.
v4: Update commit message suggested by Jani.
v5: Remove unused header file.

Cc: Shankar Uma <uma.shankar@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Vidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: Lee Shawn C <shawn.c.lee@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250901055721.219995-2-shawn.c.lee@intel.com
---

diff --git a/drivers/gpu/drm/i915/display/g4x_hdmi.c b/drivers/gpu/drm/i915/display/g4x_hdmi.c
index 108ebd97f9e4..f6e2d1ed5639 100644
--- a/drivers/gpu/drm/i915/display/g4x_hdmi.c
+++ b/drivers/gpu/drm/i915/display/g4x_hdmi.c
@@ -20,7 +20,6 @@
 #include "intel_dp_aux.h"
 #include "intel_dpio_phy.h"
 #include "intel_encoder.h"
-#include "intel_fdi.h"
 #include "intel_fifo_underrun.h"
 #include "intel_hdmi.h"
 #include "intel_hotplug.h"
@@ -136,11 +135,8 @@ static int g4x_hdmi_compute_config(struct intel_encoder *encoder,
 	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
 
-	if (HAS_PCH_SPLIT(display)) {
+	if (HAS_PCH_SPLIT(display))
 		crtc_state->has_pch_encoder = true;
-		if (!intel_fdi_compute_pipe_bpp(crtc_state))
-			return -EINVAL;
-	}
 
 	if (display->platform.g4x)
 		crtc_state->has_hdmi_sink = g4x_compute_has_hdmi_sink(state, crtc);
diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c
index cbee628eb26b..027e8ed0cea8 100644
--- a/drivers/gpu/drm/i915/display/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
@@ -55,6 +55,7 @@
 #include "intel_display_regs.h"
 #include "intel_display_types.h"
 #include "intel_dp.h"
+#include "intel_fdi.h"
 #include "intel_gmbus.h"
 #include "intel_hdcp.h"
 #include "intel_hdcp_regs.h"
@@ -2345,6 +2346,9 @@ int intel_hdmi_compute_config(struct intel_encoder *encoder,
 	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
 		pipe_config->pixel_multiplier = 2;
 
+	if (!intel_fdi_compute_pipe_bpp(pipe_config))
+		return -EINVAL;
+
 	pipe_config->has_audio =
 		intel_hdmi_has_audio(encoder, pipe_config, conn_state) &&
 		intel_audio_compute_config(encoder, pipe_config, conn_state);
diff --git a/drivers/gpu/drm/i915/display/intel_link_bw.c b/drivers/gpu/drm/i915/display/intel_link_bw.c
index 3caef7f9c7c4..d194a366ff10 100644
--- a/drivers/gpu/drm/i915/display/intel_link_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_link_bw.c
@@ -449,6 +449,7 @@ void intel_link_bw_connector_debugfs_add(struct intel_connector *connector)
 	switch (connector->base.connector_type) {
 	case DRM_MODE_CONNECTOR_DisplayPort:
 	case DRM_MODE_CONNECTOR_eDP:
+	case DRM_MODE_CONNECTOR_HDMIA:
 		break;
 	case DRM_MODE_CONNECTOR_VGA:
 	case DRM_MODE_CONNECTOR_SVIDEO:
@@ -457,11 +458,6 @@ void intel_link_bw_connector_debugfs_add(struct intel_connector *connector)
 		if (HAS_FDI(display))
 			break;
 
-		return;
-	case DRM_MODE_CONNECTOR_HDMIA:
-		if (HAS_FDI(display) && !HAS_DDI(display))
-			break;
-
 		return;
 	default:
 		return;