2023-11-21 15:09:56

by Paul Menzel

Subject: Powered off Philips TV sends corrupt EDID causing flickering

Dear Linux folks,


Connecting a USB Type-C port replicator [1] to the only USB Type-C port
of the Dell XPS 13 9360 with Debian sid/unstable and Debian’s Linux
kernel 6.10.5, and then connecting a Philips 40PFL5206H/12 TV device,
that is powered off or in standby, to the HDMI port, Linux logs:

```
[ 0.000000] Linux version 6.5.0-4-amd64
([email protected]) (gcc-13 (Debian 13.2.0-6) 13.2.0, GNU
ld (GNU Binutils for Debian) 2.41) #1 SMP PREEMPT_DYNAMIC Debian
6.5.10-1 (2023-11-03)
[…]
[ 0.000000] DMI: Dell Inc. XPS 13 9360/0596KF, BIOS 2.21.0 06/02/2022
[…]
[ 160.004836] EDID has corrupt header
[ 160.004866] [00] BAD 00 00 00 00 00 00 00 00 00 7f ff ff ff ff ff ff
[ 160.004875] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004881] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004886] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004905] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004911] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004917] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.004921] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 160.013662] Registered IR keymap rc-cec
[ 160.014001] rc rc0: DP-1 as /devices/pci0000:00/0000:00:02.0/rc/rc0
[ 160.014305] input: DP-1 as
/devices/pci0000:00/0000:00:02.0/rc/rc0/input33
[ 160.228342] EDID has corrupt header
[ 160.408917] EDID has corrupt header
```

The internal display of the laptop also switches off shortly, but comes
back after two or three seconds. This is very likely due to me
configuring the internal display to turn off once an external display is
used.

No idea, why the TV is able to transmit anything at all, when it is
turned/powered off. To avoid the flickering, would it be possible to
ignore events from displays sending such incorrect EDID?


Kind regards,

Paul

2023-11-22 10:38:59

by Jani Nikula

Subject: Re: Powered off Philips TV sends corrupt EDID causing flickering

On Tue, 21 Nov 2023, Paul Menzel <[email protected]> wrote:
> Dear Linux folks,
>
>
> Connecting a USB Type-C port replicator [1] to the only USB Type-C port
> of the Dell XPS 13 9360 with Debian sid/unstable and Debian’s Linux
> kernel 6.10.5, and then connecting a Philips 40PFL5206H/12 TV device,
> that is powered off or in standby, to the HDMI port, Linux logs:
>
> ```
> [ 0.000000] Linux version 6.5.0-4-amd64
> ([email protected]) (gcc-13 (Debian 13.2.0-6) 13.2.0, GNU
> ld (GNU Binutils for Debian) 2.41) #1 SMP PREEMPT_DYNAMIC Debian
> 6.5.10-1 (2023-11-03)
> […]
> [ 0.000000] DMI: Dell Inc. XPS 13 9360/0596KF, BIOS 2.21.0 06/02/2022
> […]
> [ 160.004836] EDID has corrupt header
> [ 160.004866] [00] BAD 00 00 00 00 00 00 00 00 00 7f ff ff ff ff ff ff
> [ 160.004875] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004881] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004886] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004905] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004911] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004917] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.004921] [00] BAD ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> [ 160.013662] Registered IR keymap rc-cec
> [ 160.014001] rc rc0: DP-1 as /devices/pci0000:00/0000:00:02.0/rc/rc0
> [ 160.014305] input: DP-1 as
> /devices/pci0000:00/0000:00:02.0/rc/rc0/input33
> [ 160.228342] EDID has corrupt header
> [ 160.408917] EDID has corrupt header
> ```
>
> The internal display of the laptop also switches off shortly, but comes
> back after two or three seconds. This is very likely due to me
> configuring the internal display to turn off once an external display is
> used.
>
> No idea, why the TV is able to transmit anything at all, when it is
> turned/powered off. To avoid the flickering, would it be possible to
> ignore events from displays sending such incorrect EDID?

Depending on how the port replicator works, this may not come from the
TV at all.

And all of this probably depends on GPU and driver, which are not
mentioned.

If it's i915, please see [1] on how to file a bug.

Thanks,
Jani.


[1] https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html

>
>
> Kind regards,
>
> Paul

--
Jani Nikula, Intel

2023-11-23 14:18:30

by Paul Menzel

Subject: Re: Powered off Philips TV sends corrupt EDID causing flickering

Dear Jani,


Thank you for your reply.

Am 22.11.23 um 11:38 schrieb Jani Nikula:
> On Tue, 21 Nov 2023, Paul Menzel wrote:

>> Connecting a USB Type-C port replicator [1] to the only USB Type-C port
>> of the Dell XPS 13 9360 with Debian sid/unstable and Debian’s Linux
>> kernel 6.10.5, and then connecting a Philips 40PFL5206H/12 TV device,
>> that is powered off or in standby, to the HDMI port, Linux logs:

[…]

> Depending on how the port replicator works, this may not come from the
> TV at all.
>
> And all of this probably depends on GPU and driver, which are not
> mentioned.

Sorry for just mentioning the laptop model. It uses the device below:

00:02.0 VGA compatible controller [0300]: Intel Corporation HD
Graphics 620 [8086:5916] (rev 02) (prog-if 00 [VGA controller])

> If it's i915, please see [1] on how to file a bug.

Thank you for taking the time to tell me the proper forum. I created the
two issues below:

1. EDID has corrupt header [2]
2. No image on Philips TV when turning on while connected over
HDMI/USB-C port replicator (`[drm] *ERROR* Link Training Unsuccessful`) [3]


Kind regards,

Paul


> [1] https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html
[2]: https://gitlab.freedesktop.org/drm/intel/-/issues/9705
[3]: https://gitlab.freedesktop.org/drm/intel/-/issues/9707