drm/vc4: hdmi: Don't poll for the infoframes status on setup

The infoframes are sent at a regular interval as a data island packet,
so we don't need to wait for them to be sent when we're setting them up.

However, we do need to poll when we're enabling since the we can't
update the packet RAM until it has been sent.

Let's add a boolean flag to tell whether we want to poll or not to
support both cases.
Suggested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201203074624.721559-1-maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -219,7 +219,8 @@ static int vc4_hdmi_connector_init(struct drm_device *dev,
 }
 
 static int vc4_hdmi_stop_packet(struct drm_encoder *encoder,
-				enum hdmi_infoframe_type type)
+				enum hdmi_infoframe_type type,
+				bool poll)
 {
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	u32 packet_id = type - 0x80;
@@ -227,6 +228,9 @@ static int vc4_hdmi_stop_packet(struct drm_encoder *encoder,
 	HDMI_WRITE(HDMI_RAM_PACKET_CONFIG,
 		   HDMI_READ(HDMI_RAM_PACKET_CONFIG) & ~BIT(packet_id));
 
+	if (!poll)
+		return 0;
+
 	return wait_for(!(HDMI_READ(HDMI_RAM_PACKET_STATUS) &
 			  BIT(packet_id)), 100);
 }
@@ -253,7 +257,7 @@ static void vc4_hdmi_write_infoframe(struct drm_encoder *encoder,
 	if (len < 0)
 		return;
 
-	ret = vc4_hdmi_stop_packet(encoder, frame->any.type);
+	ret = vc4_hdmi_stop_packet(encoder, frame->any.type, true);
 	if (ret) {
 		DRM_ERROR("Failed to wait for infoframe to go idle: %d\n", ret);
 		return;
@@ -893,7 +897,7 @@ static void vc4_hdmi_audio_reset(struct vc4_hdmi *vc4_hdmi)
 	int ret;
 
 	vc4_hdmi->audio.streaming = false;
-	ret = vc4_hdmi_stop_packet(encoder, HDMI_INFOFRAME_TYPE_AUDIO);
+	ret = vc4_hdmi_stop_packet(encoder, HDMI_INFOFRAME_TYPE_AUDIO, false);
 	if (ret)
 		dev_err(dev, "Failed to stop audio infoframe: %d\n", ret);