Message-ID: <88191cc6-e751-daa9-37f5-eda92d541098@collabora.com>
Date:   Thu, 16 Feb 2023 22:17:44 +0300
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Subject: Re: [PATCH] drm/edid: Add Vive Pro 2 to non-desktop list
Content-Language: en-US
To:     Yaroslav Boliukin <iam@lach.pw>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Cc:     Thomas Zimmermann <tzimmermann@suse.de>
References: <20220118170037.14584-1-iam@lach.pw>
 <5d5a8183-aebc-6660-9cbc-03950f9b14b8@collabora.com>
 <87v8k5vqg6.fsf@intel.com>
 <831e7daf-48ae-cea8-a5d2-3786317b3b65@collabora.com>
 <87sff9vl6j.fsf@intel.com>
 <b5f6c63e-adf3-38a6-18fb-c92c764c23f3@collabora.com>
 <d6f66bf7-356a-4bd9-fa21-a3197c0dff50@lach.pw>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
In-Reply-To: <d6f66bf7-356a-4bd9-fa21-a3197c0dff50@lach.pw>
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Precedence: bulk

On 2/16/23 21:26, Iaroslav Boliukin wrote:
> On 2/14/23 12:50, Dmitry Osipenko wrote:
>> On 2/13/23 14:50, Jani Nikula wrote:
>>> On Mon, 13 Feb 2023, Dmitry Osipenko <dmitry.osipenko@collabora.com>
>>> wrote:
>>>> On 2/13/23 12:56, Jani Nikula wrote:
>>>>> On Sun, 12 Feb 2023, Dmitry Osipenko
>>>>> <dmitry.osipenko@collabora.com> wrote:
>>>>>> Hi,
>>>>>>
>>>>>> On 1/18/22 20:00, Yaroslav Bolyukin wrote:
>>>>>>
>>>>>> Add a brief commit message, describing a user-visible effect of this
>>>>>> patch. Tell that this change prevents exposing headset as a regular
>>>>>> display to the system, while it will work with SteamVR.
>>>>>>
>>>>>>> Signed-off-by: Yaroslav Bolyukin <iam@lach.pw>
>>>>>>> ---
>>>>>>>   drivers/gpu/drm/drm_edid.c | 3 ++-
>>>>>>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
>>>>>>> index 12893e7be..fdb8f0a6f 100644
>>>>>>> --- a/drivers/gpu/drm/drm_edid.c
>>>>>>> +++ b/drivers/gpu/drm/drm_edid.c
>>>>>>> @@ -200,9 +200,10 @@ static const struct edid_quirk {
>>>>>>>       EDID_QUIRK('V', 'L', 'V', 0x91be, EDID_QUIRK_NON_DESKTOP),
>>>>>>>       EDID_QUIRK('V', 'L', 'V', 0x91bf, EDID_QUIRK_NON_DESKTOP),
>>>>>>>   -    /* HTC Vive and Vive Pro VR Headsets */
>>>>>>> +    /* HTC Vive, Vive Pro and Vive Pro 2 VR Headsets */
>>>>>>
>>>>>> Nit: I'd keep the original comment, or change it to a generic "HTC VR
>>>>>> Headsets" to prevent further comment changes
>>>>>>
>>>>>>>       EDID_QUIRK('H', 'V', 'R', 0xaa01, EDID_QUIRK_NON_DESKTOP),
>>>>>>>       EDID_QUIRK('H', 'V', 'R', 0xaa02, EDID_QUIRK_NON_DESKTOP),
>>>>>>> +    EDID_QUIRK('H', 'V', 'R', 0xaa04, EDID_QUIRK_NON_DESKTOP),
>>>>>>>         /* Oculus Rift DK1, DK2, CV1 and Rift S VR Headsets */
>>>>>>>       EDID_QUIRK('O', 'V', 'R', 0x0001, EDID_QUIRK_NON_DESKTOP),
>>>>>>>
>>>>>>> base-commit: 99613159ad749543621da8238acf1a122880144e
>>>>>>
>>>>>> Please send the v2 patch with the added EDID for Cosmos VR and the
>>>>>> addressed comments. Thanks!
>>>>>
>>>>> Yeah, we'll need to EDID to check that it doesn't have the Microsoft
>>>>> VSDB to indicate non-desktop. See 2869f599c0d8 ("drm/edid: support
>>>>> Microsoft extension for HMDs and specialized monitors").
>>>>
>>>> Do you mean to skip using the EDID_QUIRK_NON_DESKTOP if MS VSDB entry
>>>> presents in the EDID?
>>>>
>>>> These HTC EDIDs don't have MS VSDB, otherwise the quirk wouldn't be
>>>> needed.
>>>
>>> Okay, I didn't know that. I just observed that the original patch was
>>> sent before the the MS VSDB parsing was added.
>>
>> This will be good to mention in the v2 commit message.
>>
> 
> This headset does support some kind of HMD signalling, however, this is
> not a microsoft-specific extension (0xca125c) but part of the DisplayId
> spec, "Display Product Primary Use Case" field is set to "7".
> 
> The problem is, I have no idea what spec I should refer to, as I can't
> find this errata in the original spec, and the only reference to this
> value I see is in https://git.linuxtv.org/edid-decode.git utility:
> 
> https://git.linuxtv.org/edid-decode.git/tree/parse-displayid-block.cpp?ref=aa956e0dd5fb85271dde900ea1ebdda795af7f8b#n1676
> 
> I would like to implement this feature, but I need some spec reference.

The [1] says it's "VESA DisplayID Standard v2.0", which should be okay
to refer, IMO.

[1]
https://learn.microsoft.com/en-us/windows-hardware/drivers/display/specialized-monitors-edid-extension

-- 
Best regards,
Dmitry