Re: [RESEND] drm/i915/hdmi: Poll for 200 msec for TMDS_Scrambler_Status

["Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com>]

On 2/27/2026 6:46 PM, Jerome Tollet wrote:
> Hi Ankit, Ville,
>
> Gentle ping on this patch series. As confirmed in my previous testing
> (Feb 21), the SCDC polling patch works perfectly on kernel 6.19.2 with
> my Alder Lake-N (N100) + Cisco Desk Pro (CS-DESKPRO-2) setup.

As mentioned in [1], to me polling for TMDS scramble status makes sense.

Perhaps the best way would have been to work with `SCDC Read Request` 
implemented, where in the sink notifies the source to check the SCDC 
status flags, where we have bit for Scrambling_Status.

However we do not have that support. Also not all panels support this.


Since I have also contributed to the patch, I cannot review the change here.


Ville, do you think this change makes sense?


PS: I was trying my hands on SCDC RR sometime back but didnt go through. [2]


[1] 
https://lore.kernel.org/intel-xe/73e0de50-b7e3-4315-ab81-0a3ecebc2363@intel.com/

[2] https://patchwork.freedesktop.org/series/101191/


Regards,

Ankit




>
> The isolated testing showed that the SCDC polling approach alone
> resolves the 4K@60Hz HDMI issue, which aligns with both the HDMI 2.0
> spec requirements and Windows driver behavior.
>
> Is there anything else needed from my side to help move this forward?
>
> Thanks,
> Jerome