Messages in this thread | | | Subject | Re: [PATCH v3 2/5] drm/dp: fix link probing for devices supporting DP 1.4+ | From | Andrzej Hajda <> | Date | Thu, 13 Sep 2018 13:08:27 +0200 |
| |
On 28.08.2018 12:24, Damian Kos wrote: > From: Quentin Schulz <quentin.schulz@bootlin.com> > > DP 1.4 introduced a DP_EXTENDED_RCVR_CAPA_FIELD_PRESENT bit in > DP_TRAINING_AUX_RD_INTERVAL register. If set, DPCD registers from DP_DPCD_REV > to DP_ADAPTER_CAP should be retrieved starting from DP_DPCD_REV_EXTENDED. > All registers are copied except DP_DPCD_REV, DP_MAX_LINK_RATE and > DP_DOWNSTREAMPORT_PRESENT which represent the "true capabilities" of DPRX > device. > > Original DP_DPCD_REV, DP_MAX_LINK_RATE and DP_DOWNSTREAMPORT_PRESENT might > falsely return lower capabilities to "avoid interoperability issues with some > of the existing DP Source devices that malfunction when they discover the > higher capabilities within those three registers.". > > Before DP 1.4, DP_EXTENDED_RCVR_CAPA_FIELD_PRESENT bit was reserved and read 0 > so it's safe to check against it even if DP revision is <1.4 > > Signed-off-by: Damian Kos <dkos@cadence.com>
Here and in next patches signed-off-by of the author is missing.
With that fixed: Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
-- Regards Andrzej
| |