[Intel-gfx] [PATCH 4/6] drm/i915: Save sink_count for tracking changes to it

[Ander Conselvan De Oliveira]

On Tue, 2016-01-05 at 18:20 +0530, Shubhangi Shrivastava wrote:
> Sink count can change between short pulse hpd hence this patch
> adds a member variable to intel_dp so we can track any changes
> between short pulse interrupts.
> 
> 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  | 7 +++----
>  drivers/gpu/drm/i915/intel_drv.h | 1 +
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 842790e..c2e8516 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4385,14 +4385,13 @@ intel_dp_detect_dpcd(struct intel_dp *intel_dp)
>  	/* If we're HPD-aware, SINK_COUNT changes dynamically */
>  	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
>  	    intel_dp->downstream_ports[0] & DP_DS_PORT_HPD) {
> -		uint8_t reg;
>  
>  		if (intel_dp_dpcd_read_wake(&intel_dp->aux, DP_SINK_COUNT,
> -					    &reg, 1) < 0)
> +					    &intel_dp->sink_count, 1) < 0)
>  			return connector_status_unknown;
>  
> -		return DP_GET_SINK_COUNT(reg) ? connector_status_connected
> -					      :
> connector_status_disconnected;
> +		return DP_GET_SINK_COUNT(intel_dp->sink_count) ?
> +		connector_status_connected : connector_status_disconnected;

I think it would be better to have the value of intel_dp->sink_count ready for
consumption, i.e., store the result of DP_GET_SINK_COUNT().

Ander

>  	}
>  
>  	/* If no HPD, poke DDC gently */
> diff --git a/drivers/gpu/drm/i915/intel_drv.h
> b/drivers/gpu/drm/i915/intel_drv.h
> index 0438b57..88b05ba 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -757,6 +757,7 @@ struct intel_dp {
>  	uint32_t DP;
>  	int link_rate;
>  	uint8_t lane_count;
> +	uint8_t sink_count;
>  	bool has_audio;
>  	enum hdmi_force_audio force_audio;
>  	bool limited_color_range;