Re: rpi-b-rev2 can't detect hdmi display due to wrong hpd gpio pull in dts
From: Helen Koike
Date: Mon Mar 04 2019 - 16:54:11 EST
On 3/4/19 5:27 PM, Eric Anholt wrote:
> Helen Koike <helen.koike@xxxxxxxxxxxxx> writes:
>
>> Hello,
>>
>> I have a rpi-b-rev2 (two holes, 512M) and when I was trying to test vc4
>> driver, the HDMI wans't being detected.
>>
>> So I changed the hpd-gpios from ACTIVE_LOW to ACTIVE_HIGH and now it
>> works correctly. I can see that modeprint from libdrm detects correctly
>> when the display is plugged and when it is unpluggled.
>>
>> So I was wondering if this is just in my board or if there is an error
>> in the dts (which I think it's unlikely).
>>
>> In any case I am dropping this email here in case anyone else see this
>> problem, if you do, try appliying the patch below.
>
> We even have the GPIO labeled as "HDMI_HPD_P" above, and dt-blob.dts
> agrees.
You are right, I didn't notice it.
>
> Reviewed-by: Eric Anholt <eric@xxxxxxxxxx>
> Thanks! If Stefan doesn't pick this up shortly, I can.
>
Thanks for reviewing!
Helen