lkml.org 
[lkml]   [2018]   [Nov]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] drm/fb-helper: Blacklist writeback when adding connectors to fbdev
On Thu, Nov 15, 2018 at 05:32:48PM +0100, Paul Kocialkowski wrote:
> Writeback connectors do not produce any on-screen output and require
> special care for use. Such connectors are hidden from enumeration in
> DRM resources by default, but they are still picked-up by fbdev.
> This makes rather little sense since fbdev is not really adapted for
> dealing with writeback.
>
> Moreover, this is also a source of issues when userspace disables the
> CRTC (and associated plane) without detaching the CRTC from the
> connector (which is hidden by default). In this case, the connector is
> still using the CRTC, leading to am "enabled/connectors mismatch" and
> eventually the failure of the associated atomic commit. This situation
> happens with VC4 testing under IGT GPU Tools.
>
> Filter out writeback connectors in the fbdev helper to solve this.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Maxime Ripard <maxime.ripard@bootlin.com>

Thanks!
Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2018-11-19 10:29    [W:0.055 / U:4.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site