[igt-dev] [PATCH i-g-t v2] tests/kms_chamelium: Capture on type-c

[Kunal Joshi]

On 2020-04-20 at 10:55:12 +0300, Arkadiusz Hiler wrote:
> On Mon, Apr 20, 2020 at 02:56:13AM +0530, Kunal Joshi wrote:
> > Refreshing the connector everytime and also resetting the
> > state to get HPD reliably.
> 
> Code looks good, but please consider adding a bit more of explanation
> here, something like:
> 
> Chamelium uses HPD pulses to singal the need for a receiver reset using
> DPMS cycle. Some connectors (e.g. DP over TypeC) have limitations and
> will receive just a single such pulse and discard the rest. This lasts
> until we disable the mode completetly and only then reenable it.
> 
> Receiver reset is always required after we set a new mode, so let's
> disable the mode (reset_state() does that) before we switch to a new
> mode. With this we will get the HPD pulses reliably for each iteration
> over all the supoprted modes.
> 
> There are alse targeted test for HPD pulse handling - dp-hpd-*.
>
Yes arek will add this explanation in the commit keeping your rb
Thanks Kunal.