Re: [PATCH] lontium-lt9611: check a different register bit for HDMI sensing

[John Stultz]

On Tue, Nov 16, 2021 at 6:07 PM Peter Collingbourne <pcc@xxxxxxxxxx> wrote:
>
> It has been observed that with certain monitors such as the HP Z27n,
> the register 0x825e reads a value of 0x79 when the HDMI cable is
> connected and 0x78 when it is disconnected, i.e. bit 0 appears
> to correspond to the HDMI connection status and bit 2 is never
> set. Therefore, change the driver to check bit 0 instead of bit 2.
>
> Signed-off-by: Peter Collingbourne <pcc@xxxxxxxxxx>
> Link: https://linux-review.googlesource.com/id/I7e76411127e1ce4988a3f6d0c8ba5f1c3d880c23
> ---
> N.B. I don't currently have easy access to a monitor that works
> with the existing driver, so it would be great if people with
> monitors that currently work could test this patch to make sure
> that it doesn't introduce any regressions. Otherwise I will change
> it to check both bits.

So very interesting! I gave this a spin with my monitors and it works fine.

Vinod: Can you check the datasheet to see if the wrong bit is being used here?

thanks
-john