[Intel-gfx] [PATCH] drm/i915: Enable SDVO hotplug interrupts for HDMI and DVI

[Simon Farnsworth]

I was seeing a nasty 5 frame glitch every 10 seconds, caused by the
poll for connection on DVI attached by SDVO.

As my SDVO DVI supports hotplug detect interrupts, the fix is to
enable them, and hook them in to the various bits of driver
infrastructure so that they work reliably.

With lots of help from Adam Jackson <ajax at redhat.com> on IRC.

Signed-off-by: Simon Farnsworth <simon.farnsworth at onelan.co.uk>
---
Changes from v3:

 * As per Chris Wilson's comment, move the hotplug enable from
   intel_sdvo_init to intel_sdvo_dvi_init. Should correctly enable HPD
   if only one of a multifunction SDVO pair supports HPD.

Changes from v2:

 * Stylistic cleanups requested by Chris Wilson in review:
   * Make intel_sdvo_find_connector cleaner
   * Rename intel_sdvo_set_hotplug to intel_sdvo_enable_hotplug
     (reflects functionality better)
   * Remove intel_sdvo_do_hotplug

Changes from first version:

 * Don't call intel_sdvo_supports_hotplug twice - pick up the setting
   in connector->polled instead (suggested by Keith Packard in review).

 * Change subject prefix to drm/i915

 drivers/gpu/drm/i915/intel_drv.h  |    3 --
 drivers/gpu/drm/i915/intel_sdvo.c |   64 ++++++++-----------------------------
 2 files changed, 14 insertions(+), 53 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 375690b..a72d31d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -337,9 +337,6 @@ extern void intel_release_load_detect_pipe(struct intel_encoder *intel_encoder,
 					   struct drm_connector *connector,
 					   struct intel_load_detect_pipe *old);
 
-extern struct drm_connector* intel_sdvo_find(struct drm_device *dev, int sdvoB);
-extern int intel_sdvo_supports_hotplug(struct drm_connector *connector);
-extern void intel_sdvo_set_hotplug(struct drm_connector *connector, int enable);
 extern void intelfb_restore(void);
 extern void intel_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
 				    u16 blue, int regno);
diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index aa94110..27a1ead 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1208,74 +1208,31 @@ static bool intel_sdvo_get_capabilities(struct intel_sdvo *intel_sdvo, struct in
 	return true;
 }
 
-/* No use! */
-#if 0
-struct drm_connector* intel_sdvo_find(struct drm_device *dev, int sdvoB)
-{
-	struct drm_connector *connector = NULL;
-	struct intel_sdvo *iout = NULL;
-	struct intel_sdvo *sdvo;
-
-	/* find the sdvo connector */
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
-		iout = to_intel_sdvo(connector);
-
-		if (iout->type != INTEL_OUTPUT_SDVO)
-			continue;
-
-		sdvo = iout->dev_priv;
-
-		if (sdvo->sdvo_reg == SDVOB && sdvoB)
-			return connector;
-
-		if (sdvo->sdvo_reg == SDVOC && !sdvoB)
-			return connector;
-
-	}
-
-	return NULL;
-}
-
-int intel_sdvo_supports_hotplug(struct drm_connector *connector)
+static int intel_sdvo_supports_hotplug(struct intel_sdvo *intel_sdvo)
 {
 	u8 response[2];
-	u8 status;
-	struct intel_sdvo *intel_sdvo;
-	DRM_DEBUG_KMS("\n");
-
-	if (!connector)
-		return 0;
-
-	intel_sdvo = to_intel_sdvo(connector);
 
 	return intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_HOT_PLUG_SUPPORT,
 				    &response, 2) && response[0];
 }
 
-void intel_sdvo_set_hotplug(struct drm_connector *connector, int on)
+static void intel_sdvo_enable_hotplug(struct intel_encoder *encoder)
 {
+	struct intel_sdvo *intel_sdvo = to_intel_sdvo(&encoder->base);
 	u8 response[2];
 	u8 status;
-	struct intel_sdvo *intel_sdvo = to_intel_sdvo(connector);
 
 	intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_GET_ACTIVE_HOT_PLUG, NULL, 0);
 	intel_sdvo_read_response(intel_sdvo, &response, 2);
 
-	if (on) {
-		intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_GET_HOT_PLUG_SUPPORT, NULL, 0);
-		status = intel_sdvo_read_response(intel_sdvo, &response, 2);
+	intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_GET_HOT_PLUG_SUPPORT, NULL, 0);
+	status = intel_sdvo_read_response(intel_sdvo, &response, 2);
 
-		intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_ACTIVE_HOT_PLUG, &response, 2);
-	} else {
-		response[0] = 0;
-		response[1] = 0;
-		intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_ACTIVE_HOT_PLUG, &response, 2);
-	}
+	intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_ACTIVE_HOT_PLUG, &response, 2);
 
 	intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_GET_ACTIVE_HOT_PLUG, NULL, 0);
 	intel_sdvo_read_response(intel_sdvo, &response, 2);
 }
-#endif
 
 static bool
 intel_sdvo_multifunc_encoder(struct intel_sdvo *intel_sdvo)
@@ -2045,6 +2002,7 @@ intel_sdvo_dvi_init(struct intel_sdvo *intel_sdvo, int device)
 {
 	struct drm_encoder *encoder = &intel_sdvo->base.base;
 	struct drm_connector *connector;
+	struct intel_encoder *intel_encoder = to_intel_encoder(encoder);
 	struct intel_connector *intel_connector;
 	struct intel_sdvo_connector *intel_sdvo_connector;
 
@@ -2062,7 +2020,13 @@ intel_sdvo_dvi_init(struct intel_sdvo *intel_sdvo, int device)
 
 	intel_connector = &intel_sdvo_connector->base;
 	connector = &intel_connector->base;
-	connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
+	if (intel_sdvo_supports_hotplug(intel_sdvo) & (1 << device)) {
+		connector->polled = DRM_CONNECTOR_POLL_HPD;
+		intel_encoder->hot_plug = intel_sdvo_enable_hotplug;
+		intel_sdvo_enable_hotplug(intel_encoder);
+	}
+	else
+		connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
 	encoder->encoder_type = DRM_MODE_ENCODER_TMDS;
 	connector->connector_type = DRM_MODE_CONNECTOR_DVID;
 
-- 
1.7.6