drm/edid: Allow HDMI infoframe without VIC or S3D

Appedix F of HDMI 2.0 says that some HDMI sink may fail to switch from
3D to 2D mode in a timely fashion if the source simply stops sending the
HDMI infoframe. The suggested workaround is to keep sending the
infoframe even when strictly not necessary (ie. no VIC and no S3D).
HDMI 1.4 does allow for this behaviour, stating that sending the
infoframe is optional in this case.

The infoframe was first specified in HDMI 1.4, so in theory sinks
predating that may not appreciate us sending an uknown infoframe
their way. To avoid regressions let's try to determine if the sink
supports the infoframe or not. Unfortunately there's no direct way
to do that, so instead we'll just check if we managed to parse any
HDMI 1.4 4k or stereo modes from the EDID, and if so we assume the
sink will accept the infoframe. Also if the EDID contains the HDMI
2.0 HDMI Forum VSDB we can assume the sink is prepared to receive
the infoframe.

v2: Fix getting has_hdmi_infoframe from display_info
    Always fail constructing the infoframe if the display
    possibly can't handle it

Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171113170427.4150-3-ville.syrjala@linux.intel.com

10 files changed, 52 insertions, 18 deletions

diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index d58db13..86789f8 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -2233,8 +2233,9 @@ end:
 			union hdmi_infoframe frm;
 			u8 mhl_vic[] = { 0, 95, 94, 93, 98 };
 
+			/* FIXME: We need the connector here */
 			drm_hdmi_vendor_infoframe_from_display_mode(
-				&frm.vendor.hdmi, adjusted_mode);
+				&frm.vendor.hdmi, NULL, adjusted_mode);
 			vic = frm.vendor.hdmi.vic;
 			if (vic >= ARRAY_SIZE(mhl_vic))
 				vic = 0;
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index a64ce71..b172139 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -1437,7 +1437,9 @@ static void hdmi_config_vendor_specific_infoframe(struct dw_hdmi *hdmi,
 	u8 buffer[10];
 	ssize_t err;
 
-	err = drm_hdmi_vendor_infoframe_from_display_mode(&frame, mode);
+	err = drm_hdmi_vendor_infoframe_from_display_mode(&frame,
+							  &hdmi->connector,
+							  mode);
 	if (err < 0)
 		/*
 		 * Going into that statement does not means vendor infoframe
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 749d07a..9ada0cc 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3393,6 +3393,7 @@ static int
 do_hdmi_vsdb_modes(struct drm_connector *connector, const u8 *db, u8 len,
 		   const u8 *video_db, u8 video_len)
 {
+	struct drm_display_info *info = &connector->display_info;
 	int modes = 0, offset = 0, i, multi_present = 0, multi_len;
 	u8 vic_len, hdmi_3d_len = 0;
 	u16 mask;
@@ -3520,6 +3521,8 @@ do_hdmi_vsdb_modes(struct drm_connector *connector, const u8 *db, u8 len,
 	}
 
 out:
+	if (modes > 0)
+		info->has_hdmi_infoframe = true;
 	return modes;
 }
 
@@ -4243,6 +4246,8 @@ static void drm_parse_hdmi_forum_vsdb(struct drm_connector *connector,
 	struct drm_display_info *display = &connector->display_info;
 	struct drm_hdmi_info *hdmi = &display->hdmi;
 
+	display->has_hdmi_infoframe = true;
+
 	if (hf_vsdb[6] & 0x80) {
 		hdmi->scdc.supported = true;
 		if (hf_vsdb[6] & 0x40)
@@ -4416,6 +4421,7 @@ static void drm_add_display_info(struct drm_connector *connector,
 	info->cea_rev = 0;
 	info->max_tmds_clock = 0;
 	info->dvi_dual = false;
+	info->has_hdmi_infoframe = false;
 
 	if (edid->revision < 3)
 		return;
@@ -4903,6 +4909,7 @@ s3d_structure_from_display_mode(const struct drm_display_mode *mode)
  * drm_hdmi_vendor_infoframe_from_display_mode() - fill an HDMI infoframe with
  * data from a DRM display mode
  * @frame: HDMI vendor infoframe
+ * @connector: the connector
  * @mode: DRM display mode
  *
  * Note that there's is a need to send HDMI vendor infoframes only when using a
@@ -4913,8 +4920,15 @@ s3d_structure_from_display_mode(const struct drm_display_mode *mode)
  */
 int
 drm_hdmi_vendor_infoframe_from_display_mode(struct hdmi_vendor_infoframe *frame,
+					    struct drm_connector *connector,
 					    const struct drm_display_mode *mode)
 {
+	/*
+	 * FIXME: sil-sii8620 doesn't have a connector around when
+	 * we need one, so we have to be prepared for a NULL connector.
+	 */
+	bool has_hdmi_infoframe = connector ?
+		connector->display_info.has_hdmi_infoframe : false;
 	int err;
 	u32 s3d_flags;
 	u8 vic;
@@ -4922,11 +4936,21 @@ drm_hdmi_vendor_infoframe_from_display_mode(struct hdmi_vendor_infoframe *frame,
 	if (!frame || !mode)
 		return -EINVAL;
 
+	if (!has_hdmi_infoframe)
+		return -EINVAL;
+
 	vic = drm_match_hdmi_mode(mode);
 	s3d_flags = mode->flags & DRM_MODE_FLAG_3D_MASK;
 
-	if (!vic && !s3d_flags)
-		return -EINVAL;
+	/*
+	 * Even if it's not absolutely necessary to send the infoframe
+	 * (ie.vic==0 and s3d_struct==0) we will still send it if we
+	 * know that the sink can handle it. This is based on a
+	 * suggestion in HDMI 2.0 Appendix F. Apparently some sinks
+	 * have trouble realizing that they shuld switch from 3D to 2D
+	 * mode if the source simply stops sending the infoframe when
+	 * it wants to switch from 3D to 2D.
+	 */
 
 	if (vic && s3d_flags)
 		return -EINVAL;
@@ -4935,10 +4959,8 @@ drm_hdmi_vendor_infoframe_from_display_mode(struct hdmi_vendor_infoframe *frame,
 	if (err < 0)
 		return err;
 
-	if (vic)
-		frame->vic = vic;
-	else
-		frame->s3d_struct = s3d_structure_from_display_mode(mode);
+	frame->vic = vic;
+	frame->s3d_struct = s3d_structure_from_display_mode(mode);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
index 82d1b7e..a4b75a4 100644
--- a/drivers/gpu/drm/exynos/exynos_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
@@ -829,7 +829,8 @@ static void hdmi_reg_infoframes(struct hdmi_context *hdata)
 		DRM_INFO("%s: invalid AVI infoframe (%d)\n", __func__, ret);
 	}
 
-	ret = drm_hdmi_vendor_infoframe_from_display_mode(&frm.vendor.hdmi, m);
+	ret = drm_hdmi_vendor_infoframe_from_display_mode(&frm.vendor.hdmi,
+							  &hdata->connector, m);
 	if (!ret)
 		ret = hdmi_vendor_infoframe_pack(&frm.vendor.hdmi, buf,
 				sizeof(buf));
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 5132dc8..59247a4 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -512,12 +512,14 @@ static void intel_hdmi_set_spd_infoframe(struct drm_encoder *encoder,
 
 static void
 intel_hdmi_set_hdmi_infoframe(struct drm_encoder *encoder,
-			      const struct intel_crtc_state *crtc_state)
+			      const struct intel_crtc_state *crtc_state,
+			      const struct drm_connector_state *conn_state)
 {
 	union hdmi_infoframe frame;
 	int ret;
 
 	ret = drm_hdmi_vendor_infoframe_from_display_mode(&frame.vendor.hdmi,
+							  conn_state->connector,
 							  &crtc_state->base.adjusted_mode);
 	if (ret < 0)
 		return;
@@ -584,7 +586,7 @@ static void g4x_set_infoframes(struct drm_encoder *encoder,
 
 	intel_hdmi_set_avi_infoframe(encoder, crtc_state);
 	intel_hdmi_set_spd_infoframe(encoder, crtc_state);
-	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state);
+	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state, conn_state);
 }
 
 static bool hdmi_sink_is_deep_color(const struct drm_connector_state *conn_state)
@@ -725,7 +727,7 @@ static void ibx_set_infoframes(struct drm_encoder *encoder,
 
 	intel_hdmi_set_avi_infoframe(encoder, crtc_state);
 	intel_hdmi_set_spd_infoframe(encoder, crtc_state);
-	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state);
+	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state, conn_state);
 }
 
 static void cpt_set_infoframes(struct drm_encoder *encoder,
@@ -768,7 +770,7 @@ static void cpt_set_infoframes(struct drm_encoder *encoder,
 
 	intel_hdmi_set_avi_infoframe(encoder, crtc_state);
 	intel_hdmi_set_spd_infoframe(encoder, crtc_state);
-	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state);
+	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state, conn_state);
 }
 
 static void vlv_set_infoframes(struct drm_encoder *encoder,
@@ -821,7 +823,7 @@ static void vlv_set_infoframes(struct drm_encoder *encoder,
 
 	intel_hdmi_set_avi_infoframe(encoder, crtc_state);
 	intel_hdmi_set_spd_infoframe(encoder, crtc_state);
-	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state);
+	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state, conn_state);
 }
 
 static void hsw_set_infoframes(struct drm_encoder *encoder,
@@ -854,7 +856,7 @@ static void hsw_set_infoframes(struct drm_encoder *encoder,
 
 	intel_hdmi_set_avi_infoframe(encoder, crtc_state);
 	intel_hdmi_set_spd_infoframe(encoder, crtc_state);
-	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state);
+	intel_hdmi_set_hdmi_infoframe(encoder, crtc_state, conn_state);
 }
 
 void intel_dp_dual_mode_set_tmds_output(struct intel_hdmi *hdmi, bool enable)
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
index b787910..59a1102 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
@@ -1054,7 +1054,8 @@ static int mtk_hdmi_setup_vendor_specific_infoframe(struct mtk_hdmi *hdmi,
 	u8 buffer[10];
 	ssize_t err;
 
-	err = drm_hdmi_vendor_infoframe_from_display_mode(&frame, mode);
+	err = drm_hdmi_vendor_infoframe_from_display_mode(&frame,
+							  &hdmi->conn, mode);
 	if (err) {
 		dev_err(hdmi->dev,
 			"Failed to get vendor infoframe from mode: %zd\n", err);
diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 9c61e76..fdfeae1 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -2756,7 +2756,8 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
 			= hdmi_infoframe_pack(&avi_frame, args.infoframes, 17);
 	}
 
-	ret = drm_hdmi_vendor_infoframe_from_display_mode(&vendor_frame.vendor.hdmi, mode);
+	ret = drm_hdmi_vendor_infoframe_from_display_mode(&vendor_frame.vendor.hdmi,
+							  &nv_connector->base, mode);
 	if (!ret) {
 		/* We have a Vendor InfoFrame, populate it to the display */
 		args.pwr.vendor_infoframe_length
diff --git a/drivers/gpu/drm/rockchip/inno_hdmi.c b/drivers/gpu/drm/rockchip/inno_hdmi.c
index ee584d8..fab30927 100644
--- a/drivers/gpu/drm/rockchip/inno_hdmi.c
+++ b/drivers/gpu/drm/rockchip/inno_hdmi.c
@@ -282,6 +282,7 @@ static int inno_hdmi_config_video_vsi(struct inno_hdmi *hdmi,
 	int rc;
 
 	rc = drm_hdmi_vendor_infoframe_from_display_mode(&frame.vendor.hdmi,
+							 &hdmi->connector,
 							 mode);
 
 	return inno_hdmi_upload_frame(hdmi, rc, &frame, INFOFRAME_VSI,
diff --git a/drivers/gpu/drm/sti/sti_hdmi.c b/drivers/gpu/drm/sti/sti_hdmi.c
index 1c7423f..4ea1cc1 100644
--- a/drivers/gpu/drm/sti/sti_hdmi.c
+++ b/drivers/gpu/drm/sti/sti_hdmi.c
@@ -515,7 +515,9 @@ static int hdmi_vendor_infoframe_config(struct sti_hdmi *hdmi)
 
 	DRM_DEBUG_DRIVER("\n");
 
-	ret = drm_hdmi_vendor_infoframe_from_display_mode(&infoframe, mode);
+	ret = drm_hdmi_vendor_infoframe_from_display_mode(&infoframe,
+							  hdmi->drm_connector,
+							  mode);
 	if (ret < 0) {
 		/*
 		 * Going into that statement does not means vendor infoframe
diff --git a/drivers/gpu/drm/zte/zx_hdmi.c b/drivers/gpu/drm/zte/zx_hdmi.c
index b8abb1b..13ea90f 100644
--- a/drivers/gpu/drm/zte/zx_hdmi.c
+++ b/drivers/gpu/drm/zte/zx_hdmi.c
@@ -108,6 +108,7 @@ static int zx_hdmi_config_video_vsi(struct zx_hdmi *hdmi,
 	int ret;
 
 	ret = drm_hdmi_vendor_infoframe_from_display_mode(&frame.vendor.hdmi,
+							  &hdmi->connector,
 							  mode);
 	if (ret) {
 		DRM_DEV_ERROR(hdmi->dev, "failed to get vendor infoframe: %d\n",