[Intel-gfx] [PATCH 5/5] drm/i915: force full detect on sink count change

[Ander Conselvan De Oliveira]

On Thu, 2016-03-24 at 12:21 +0000, Shrivastava, Shubhangi wrote:
> Hi Daniel,
> 
> Is something else required for this patch series (5 patches) to be merged?

It needs to please CI. The errors reported are probably not caused by this
series, but at this point is probably better to rebase and resend. CI seems to
be a lot happier lately. :)

Ander

> 
> Thanks and Regards,
> Shubhangi Shrivastava.
> 
> -----Original Message-----
> From: Ander Conselvan De Oliveira [mailto:conselvan2 at gmail.com] 
> Sent: Wednesday, January 20, 2016 8:07 PM
> To: Shrivastava, Shubhangi <shubhangi.shrivastava at intel.com>; 
> intel-gfx at lists.freedesktop.org
> Subject: Re: [Intel-gfx] [PATCH 5/5] drm/i915: force full detect on sink count
> change
> 
> On Tue, 2016-01-19 at 16:07 +0530, Shubhangi Shrivastava wrote:
> > This patch checks for changes in sink count between short pulse hpds 
> > and forces full detect when there is a change.
> > 
> > This will allow both detection of hotplug and unplug of panels through 
> > dongles that give only short pulse for such events.
> > 
> > v2: changed variable type from u8 to bool (Jani)
> >     return immediately if perform_full_detect is set(Siva)
> > 
> > v3: changed method of determining full detection from using
> >     pointer to return code (Siva)
> > 
> > v4: changed comments to indicate meaning of return value of
> >     intel_dp_short_pulse and explain the use of return value
> >     from intel_dp_get_dpcd in intel_dp_short_pulse (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>
> 
> Reviewed-by: Ander Conselvan de Oliveira <conselvan2 at gmail.com>
> 
> > ---
> >  drivers/gpu/drm/i915/intel_dp.c | 33 
> > +++++++++++++++++++++++++++------
> >  1 file changed, 27 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c 
> > b/drivers/gpu/drm/i915/intel_dp.c index cdf4919..120d263 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4325,12 +4325,19 @@ intel_dp_check_link_status(struct intel_dp
> > *intel_dp)
> >   *  2. Configure link according to Receiver Capabilities
> >   *  3. Use Link Training from 2.5.3.3 and 3.5.1.3
> >   *  4. Check link status on receipt of hot-plug interrupt
> > + *
> > + * intel_dp_short_pulse -  handles short pulse interrupts
> > + * when full detection is not required.
> > + * Returns %true if short pulse is handled and full detection
> > + * is NOT required and %false otherwise.
> >   */
> > -static void
> > +static bool
> >  intel_dp_short_pulse(struct intel_dp *intel_dp)  {
> >  	struct drm_device *dev = intel_dp_to_dev(intel_dp);
> >  	u8 sink_irq_vector;
> > +	u8 old_sink_count = intel_dp->sink_count;
> > +	bool ret;
> >  
> >  	/*
> >  	 * Clearing compliance test variables to allow capturing @@ -4340,9
> > +4347,17 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
> >  	intel_dp->compliance_test_type = 0;
> >  	intel_dp->compliance_test_data = 0;
> >  
> > -	/* Now read the DPCD to see if it's actually running */
> > -	if (!intel_dp_get_dpcd(intel_dp)) {
> > -		return;
> > +	/*
> > +	 * Now read the DPCD to see if it's actually running
> > +	 * If the current value of sink count doesn't match with
> > +	 * the value that was stored earlier or dpcd read failed
> > +	 * we need to do full detection
> > +	 */
> > +	ret = intel_dp_get_dpcd(intel_dp);
> > +
> > +	if ((old_sink_count != intel_dp->sink_count) || !ret) {
> > +		/* No need to proceed if we are going to do full detect */
> > +		return false;
> >  	}
> >  
> >  	/* Try to read the source of the interrupt */ @@ -4362,6 +4377,8 @@
> > intel_dp_short_pulse(struct intel_dp *intel_dp)
> >  	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> >  	intel_dp_check_link_status(intel_dp);
> >  	drm_modeset_unlock(&dev->mode_config.connection_mutex);
> > +
> > +	return true;
> >  }
> >  
> >  /* XXX this is probably wrong for multiple downstream ports */ @@ 
> > -5086,8 +5103,12 @@ intel_dp_hpd_pulse(struct intel_digital_port 
> > *intel_dig_port, bool long_hpd)
> >  			}
> >  		}
> >  
> > -		if (!intel_dp->is_mst)
> > -			intel_dp_short_pulse(intel_dp);
> > +		if (!intel_dp->is_mst) {
> > +			if (!intel_dp_short_pulse(intel_dp)) {
> > +				intel_dp_long_pulse(intel_dp
> > ->attached_connector);
> > +				goto put_power;
> > +			}
> > +		}
> >  	}
> >  
> >  	ret = IRQ_HANDLED;