lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 6 Oct 2015 15:01:36 -0300 From: Fabio Estevam <festevam@...il.com> To: Russell King <rmk+kernel@....linux.org.uk> Cc: linux-rockchip@...ts.infradead.org, DRI mailing list <dri-devel@...ts.freedesktop.org>, linux-kernel <linux-kernel@...r.kernel.org>, "linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org>, Fabio Estevam <fabio.estevam@...escale.com>, Yakir Yang <ykk@...k-chips.com>, Andy Yan <andy.yan@...k-chips.com> Subject: Re: [PATCH 11/12] drm: bridge/dw_hdmi: add connector mode forcing On Sat, Aug 8, 2015 at 1:04 PM, Russell King <rmk+kernel@....linux.org.uk> wrote: > When connected to HDMI sources, some DVI monitors de-assert their HPD > signal and TDMS loads for one seconds every four seconds when there is > no signal present on the connection. > > Unfortunately, this behaviour is indistinguishable from a proper HDMI > setup with an AV receiver in the path to the display: the HDMI spec > requires us to detect HPD deassertions as short as 100ms, which indicate > that the EDID has changed. > > Since it is possible to connect a DVI monitor to an AV receiver and then > to a HDMI source, merely working around this by detecting the lack of > HDMI vendor block in the EDID is insufficient - the AV receiver is at > liberty to modify the EDID as it sees fit, and it will place its own > parameters into the EDID including the HDMI vendor block. > > DRM has support for forcing the state of a connector, which we should > implement to allow us to work around these broken DVI monitors - we can > tell DRM to force the connection state to indicate that there is always > a device connected to work around this problem. Although this requires > manual configuration, it is better than nothing at all. > > When a forced connection state has been set, there is no point handling > our RXSENSE interrupts, so disable them in this circumstance. > > Signed-off-by: Russell King <rmk+kernel@....linux.org.uk> Reviewed-by: Fabio Estevam@...escale.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists