Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-24 Thread Daniel Vetter
On Fri, Nov 25, 2016 at 1:23 AM, Laurent Pinchart wrote: >> > Daniel, why do we have an API the is clearly related to interrupt handling >> > but requires the caller to implement a workqueue ? >> >> Because in general you need that workqueue anyway, and up to now there was >> no driver ever who di

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-24 Thread Laurent Pinchart
Hi Daniel, On Wednesday 23 Nov 2016 08:55:37 Daniel Vetter wrote: > On Tue, Nov 22, 2016 at 08:23:38PM +0200, Laurent Pinchart wrote: > > On Tuesday 22 Nov 2016 10:07:53 John Stultz wrote: > >> On Tue, Nov 22, 2016 at 9:38 AM, John Stultz wrote: > >>> Interestingly, without the msleep added in thi

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread Daniel Vetter
On Tue, Nov 22, 2016 at 08:23:38PM +0200, Laurent Pinchart wrote: > Hi John, > > (CC'ing Daniel) > > On Tuesday 22 Nov 2016 10:07:53 John Stultz wrote: > > On Tue, Nov 22, 2016 at 9:38 AM, John Stultz wrote: > > > Interestingly, without the msleep added in this patch, removing the > > > wait_eve

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread John Stultz
On Tue, Nov 22, 2016 at 10:23 AM, Laurent Pinchart wrote: > On Tuesday 22 Nov 2016 10:07:53 John Stultz wrote: >> On Tue, Nov 22, 2016 at 9:38 AM, John Stultz wrote: >> > Interestingly, without the msleep added in this patch, removing the >> > wait_event_interruptible_timeout() method in adv7511_

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread Laurent Pinchart
Hi John, (CC'ing Daniel) On Tuesday 22 Nov 2016 10:07:53 John Stultz wrote: > On Tue, Nov 22, 2016 at 9:38 AM, John Stultz wrote: > > Interestingly, without the msleep added in this patch, removing the > > wait_event_interruptible_timeout() method in adv7511_wait_for_edid() > > and using the pol

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread John Stultz
On Tue, Nov 22, 2016 at 9:38 AM, John Stultz wrote: > > Interestingly, without the msleep added in this patch, removing the > wait_event_interruptible_timeout() method in adv7511_wait_for_edid() > and using the polling loop seems to make things just as reliable. So > maybe something is off with th

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread John Stultz
On Tue, Nov 22, 2016 at 12:25 AM, Laurent Pinchart wrote: > On Monday 21 Nov 2016 16:37:31 John Stultz wrote: >> Secton 4.1 of the adv7511 programming guide advises one waits >> 200ms after powering on the chip before trying to communicate >> with it via i2c. Not doing so can cause reliability iss

Re: [RFC][PATCH 2/3] drm/bridge: adv7511: Add 200ms delay on power-on

2016-11-22 Thread Laurent Pinchart
Hi John, Thank you for the patch. On Monday 21 Nov 2016 16:37:31 John Stultz wrote: > Secton 4.1 of the adv7511 programming guide advises one waits > 200ms after powering on the chip before trying to communicate > with it via i2c. Not doing so can cause reliability issues when > probing the EDID.