[PATCH 14/20] drm/i915/dp: Return early if getting/ackink link service IRQs fails

[Luca Coelho]

On Thu, 2025-06-26 at 11:20 +0300, Imre Deak wrote:
> If getting/acking the link service IRQs fail, the short HPD handler
> should bail out, falling back to a full connector detection as in case
> of any AUX access failures during the HPD handling. Do this by
> separating the getting/acking and handling steps of the IRQs.
> 
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 35 +++++++++++++++++--------
>  1 file changed, 24 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index cfbe7c6f896ab..2ba4a810f22c2 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -5428,33 +5428,43 @@ static void intel_dp_handle_device_service_irq(struct intel_dp *intel_dp, u8 irq
>  		drm_dbg_kms(display->drm, "Sink specific irq unhandled\n");
>  }
>  
> -static bool intel_dp_check_link_service_irq(struct intel_dp *intel_dp)
> +static bool intel_dp_get_and_ack_link_service_irq(struct intel_dp *intel_dp, u8 *irq_mask)
>  {
> -	struct intel_display *display = to_intel_display(intel_dp);
> -	bool reprobe_needed = false;
>  	u8 val;
>  
> +	*irq_mask = 0;
> +
>  	if (intel_dp->dpcd[DP_DPCD_REV] < DP_DPCD_REV_12)
> -		return false;
> +		return true;
>  
>  	if (drm_dp_dpcd_readb(&intel_dp->aux,
>  			      DP_LINK_SERVICE_IRQ_VECTOR_ESI0, &val) != 1)
> -		return true;
> +		return false;
>  
>  	if (!val)
> -		return false;
> +		return true;
>  
>  	if (drm_dp_dpcd_writeb(&intel_dp->aux,
>  			       DP_LINK_SERVICE_IRQ_VECTOR_ESI0, val) != 1)
> -		return true;
> +		return false;
>  
> -	if (val & RX_CAP_CHANGED)
> +	*irq_mask = val;
> +
> +	return true;
> +}
> +
> +static bool intel_dp_handle_link_service_irq(struct intel_dp *intel_dp, u8 irq_mask)
> +{
> +	struct intel_display *display = to_intel_display(intel_dp);
> +	bool reprobe_needed = false;
> +
> +	if (irq_mask & RX_CAP_CHANGED)
>  		reprobe_needed = true;
>  
> -	if (val & HDMI_LINK_STATUS_CHANGED)
> +	if (irq_mask & HDMI_LINK_STATUS_CHANGED)
>  		intel_dp_handle_hdmi_link_status_change(intel_dp);
>  
> -	if ((val & DP_TUNNELING_IRQ) &&
> +	if ((irq_mask & DP_TUNNELING_IRQ) &&
>  	    drm_dp_tunnel_handle_irq(display->dp_tunnel_mgr,
>  				     &intel_dp->aux))
>  		reprobe_needed = true;
> @@ -5499,7 +5509,10 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
>  
>  	intel_dp_handle_device_service_irq(intel_dp, irq_mask);
>  
> -	if (intel_dp_check_link_service_irq(intel_dp))
> +	if (!intel_dp_get_and_ack_link_service_irq(intel_dp, &irq_mask))
> +		return false;
> +
> +	if (intel_dp_handle_link_service_irq(intel_dp, irq_mask))
>  		reprobe_needed = true;
>  
>  	/* Handle CEC interrupts, if any */

Same as with the previous patch.  With a short comment about the bool
meaning:

Reviewed-by: Luca Coelho <luciano.coelho at intel.com>

--
Cheers,
Luca.