Commit 92fd8fd1 authored by Keith Packard's avatar Keith Packard
Browse files

drm/i915: Use dp_detect_common in hotplug helper function 



This uses the common dpcd reading routine, i915_dp_detect_common,
instead of open-coding a call to intel_dp_aux_native_read. Besides
reducing duplicated code, this also gains the read retries which
may be necessary when a cable is first plugged back in and the link
needs to be retrained.

Signed-off-by: default avatarKeith Packard <keithp@keithp.com>
Reviewed-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: default avatarAdam Jackson <ajax@redhat.com>
parent 40ee3381

drivers/gpu/drm/i915/intel_dp.c

+19 −20
Original line number Diff line number Diff line
@@ -1567,6 +1567,20 @@ intel_dp_link_down(struct intel_dp *intel_dp) 
	POSTING_READ(intel_dp->output_reg);

}



static enum drm_connector_status

i915_dp_detect_common(struct intel_dp *intel_dp)

{

	enum drm_connector_status status = connector_status_disconnected;



	if (intel_dp_aux_native_read_retry(intel_dp, 0x000, intel_dp->dpcd,

					   sizeof (intel_dp->dpcd)) &&

	    (intel_dp->dpcd[DP_DPCD_REV] != 0)) {

		status = connector_status_connected;

	}



	return status;

}



/*

 * According to DP spec

 * 5.1.2:
@@ -1579,44 +1593,29 @@ intel_dp_link_down(struct intel_dp *intel_dp) 
static void

intel_dp_check_link_status(struct intel_dp *intel_dp)

{

	int ret;



	if (!intel_dp->base.base.crtc)

		return;



	/* Try to read receiver status if the link appears to be up */

	if (!intel_dp_get_link_status(intel_dp)) {

		intel_dp_link_down(intel_dp);

		return;

	}



	/* Try to read receiver status if the link appears to be up */

	ret = intel_dp_aux_native_read(intel_dp,

				       0x000, intel_dp->dpcd,

				       sizeof (intel_dp->dpcd));

	if (ret != sizeof(intel_dp->dpcd)) {

	/* Now read the DPCD to see if it's actually running */

	if (i915_dp_detect_common(intel_dp) != connector_status_connected) {

		intel_dp_link_down(intel_dp);

		return;

	}



	if (!intel_channel_eq_ok(intel_dp)) {

		DRM_DEBUG_KMS("%s: channel EQ not ok, retraining\n",

			      drm_get_encoder_name(&intel_dp->base.base));

		intel_dp_start_link_train(intel_dp);

		intel_dp_complete_link_train(intel_dp);

	}

}



static enum drm_connector_status

i915_dp_detect_common(struct intel_dp *intel_dp)

{

	enum drm_connector_status status = connector_status_disconnected;



	if (intel_dp_aux_native_read_retry(intel_dp, 0x000, intel_dp->dpcd,

					   sizeof (intel_dp->dpcd)) &&

	    (intel_dp->dpcd[DP_DPCD_REV] != 0))

		status = connector_status_connected;



	return status;

}



static enum drm_connector_status

ironlake_dp_detect(struct intel_dp *intel_dp)

{

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