[Intel-gfx] [PATCH 1/6] drm/i915: Splitting intel_dp_detect

[Ander Conselvan De Oliveira]

On Tue, 2016-01-05 at 18:20 +0530, Shubhangi Shrivastava wrote:
> intel_dp_detect() is called for not just detection but
> during modes enumeration as well. Repeating the whole
> sequence during each of these calls is wasteful and
> time consuming.
> This patch moves probing for panel, DPCD read etc done in
> intel_dp_detect() to a new function intel_dp_long_pulse().
> Note that the behavior of intel_dp_detect() is changed to
> report connected or disconnected depending on whether the
> EDID is available or not.
> This change will be required by further patches in the series
> to avoid performing duplicated DPCD operations on hotplug.
> 
> v2: Moved a hunk to next patch of the series.
>     Moved intel_dp_unset_edid to out. (Ander)
> v3: Rephrased commit message and intel_dp_unset_dp() is called
>     within intel_dp_set_dp() to free the previous EDID. (Ander)
> 
> Tested-by: Nathan D Ciobanu <nathan.d.ciobanu at intel.com>
> Signed-off-by: Sivakumar Thulasimani <sivakumar.thulasimani at intel.com>
> Signed-off-by: Shubhangi Shrivastava <shubhangi.shrivastava at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 56 +++++++++++++++++++++++++---------------
> -
>  1 file changed, 35 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 796e3d3..e3b4208 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -129,6 +129,7 @@ static void edp_panel_vdd_off(struct intel_dp *intel_dp,
> bool sync);
>  static void vlv_init_panel_power_sequencer(struct intel_dp *intel_dp);
>  static void vlv_steal_power_sequencer(struct drm_device *dev,
>  				      enum pipe pipe);
> +static void intel_dp_unset_edid(struct intel_dp *intel_dp);
>  
>  static unsigned int intel_dp_unused_lane_mask(int lane_count)
>  {
> @@ -4587,6 +4588,7 @@ intel_dp_set_edid(struct intel_dp *intel_dp)
>  	struct intel_connector *intel_connector = intel_dp
> ->attached_connector;
>  	struct edid *edid;
>  
> +	intel_dp_unset_edid(intel_dp);
>  	edid = intel_dp_get_edid(intel_dp);
>  	intel_connector->detect_edid = edid;
>  
> @@ -4607,9 +4609,10 @@ intel_dp_unset_edid(struct intel_dp *intel_dp)
>  	intel_dp->has_audio = false;
>  }
>  
> -static enum drm_connector_status
> -intel_dp_detect(struct drm_connector *connector, bool force)
> +static void
> +intel_dp_long_pulse(struct intel_connector *intel_connector)
>  {
> +	struct drm_connector *connector = &intel_connector->base;
>  	struct intel_dp *intel_dp = intel_attached_dp(connector);
>  	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>  	struct intel_encoder *intel_encoder = &intel_dig_port->base;
> @@ -4619,17 +4622,6 @@ intel_dp_detect(struct drm_connector *connector, bool
> force)
>  	bool ret;
>  	u8 sink_irq_vector;
>  
> -	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
> -		      connector->base.id, connector->name);
> -	intel_dp_unset_edid(intel_dp);
> -
> -	if (intel_dp->is_mst) {
> -		/* MST devices are disconnected from a monitor POV */
> -		if (intel_encoder->type != INTEL_OUTPUT_EDP)
> -			intel_encoder->type = INTEL_OUTPUT_DISPLAYPORT;
> -		return connector_status_disconnected;
> -	}
> -
>  	power_domain = intel_display_port_aux_power_domain(intel_encoder);
>  	intel_display_power_get(to_i915(dev), power_domain);
>  
> @@ -4653,14 +4645,8 @@ intel_dp_detect(struct drm_connector *connector, bool
> force)
>  	intel_dp_probe_oui(intel_dp);
>  
>  	ret = intel_dp_probe_mst(intel_dp);
> -	if (ret) {
> -		/* if we are in MST mode then this connector
> -		   won't appear connected or have anything with EDID on it */
> -		if (intel_encoder->type != INTEL_OUTPUT_EDP)
> -			intel_encoder->type = INTEL_OUTPUT_DISPLAYPORT;

This deletion is new in this version of the patch. I think we still need the
hunk above, otherwise we might not properly update the encoder type when we
switch from an HDMI sink connected through a level shifter to an MST sink.

Ander


> -		status = connector_status_disconnected;
> +	if (ret)
>  		goto out;
> -	}
>  
>  	/*
>  	 * Clearing NACK and defer counts to get their exact values
> @@ -4691,8 +4677,36 @@ intel_dp_detect(struct drm_connector *connector, bool
> force)
>  	}
>  
>  out:
> +	if (status != connector_status_connected)
> +		intel_dp_unset_edid(intel_dp);
>  	intel_display_power_put(to_i915(dev), power_domain);
> -	return status;
> +	return;
> +}
> +
> +static enum drm_connector_status
> +intel_dp_detect(struct drm_connector *connector, bool force)
> +{
> +	struct intel_dp *intel_dp = intel_attached_dp(connector);
> +	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
> +	struct intel_encoder *intel_encoder = &intel_dig_port->base;
> +	struct intel_connector *intel_connector =
> to_intel_connector(connector);
> +
> +	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
> +		     connector->base.id, connector->name);
> +
> +	if (intel_dp->is_mst) {
> +		/* MST devices are disconnected from a monitor POV */
> +		if (intel_encoder->type != INTEL_OUTPUT_EDP)
> +			intel_encoder->type = INTEL_OUTPUT_DISPLAYPORT;
> +		return connector_status_disconnected;
> +	}
> +
> +	intel_dp_long_pulse(intel_dp->attached_connector);
> +
> +	if (intel_connector->detect_edid)
> +		return connector_status_connected;
> +	else
> +		return connector_status_disconnected;
>  }
>  
>  static void