Re: [PATCH] Add unusal uas devices reported by Umbrel users

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 3/7/21 5:03 PM, Aaron Dewes wrote:
> 
> Am 07.03.21 um 16:53 schrieb Hans de Goede:
>> Hi,
>>
>> First of all I'm not the maintainer of this file, to find the
>> right email address to submit patches to see:
>>
>>
>> [hans@x1 linux]$ scripts/get_maintainer.pl -f drivers/usb/storage/uas.c
>> Oliver Neukum <oneukum@suse.com> (maintainer:USB ATTACHED SCSI)
>> Alan Stern <stern@rowland.harvard.edu> (maintainer:USB MASS STORAGE DRIVER)
>> Greg Kroah-Hartman <gregkh@linuxfoundation.org> (supporter:USB SUBSYSTEM)
>> linux-usb@vger.kernel.org (open list:USB ATTACHED SCSI)
>> linux-scsi@vger.kernel.org (open list:USB ATTACHED SCSI)
>> usb-storage@lists.one-eyed-alien.net (open list:USB MASS STORAGE DRIVER)
>> linux-kernel@vger.kernel.org (open list)
> 
> Then the beginning of that file needs to be updated, because a comment
> at the beginning said:
> 
> 
> /*
>  * If you edit this file, please try to keep it sorted first by VendorID,
>  * then by ProductID.
>  *
>  * If you want to add an entry for this file, be sure to include the
>  * following information:
>  *      - a patch that adds the entry for your device, including your
>  *        email address right above the entry (plus maybe a brief
>  *        explanation of the reason for the entry),
>  *      - lsusb -v output for the device
>  * Send your submission to Hans de Goede <hdegoede@redhat.com>
>  * and don't forget to CC: the USB development list
> <linux-usb@vger.kernel.org>
>  */

Oh, good point, thank you for pointing that out.

So we either need to update the email address here, or just drop the
email address altogether, maybe include the:

scripts/get_maintainer.pl -f drivers/usb/storage/uas.c

Command in the comment instead.

Oliver, what would be your preference for fixing the comment to
no longer point to my email address ?

<snip>

>> At the top I indicated that you should split this in per
>> model patches, but that was before I figured out most of
>> these problems are beeing seen on Raspberry Pi-s (and likely
>> on Raspberry Pi-s only).
>>
>> What might be worth considering is disabling bulk-stream support
>> on the Pi-s XHCI controller by setting the  XHCI_BROKEN_STREAMS
>> flag in xhci->quirks for that controller.  This will disable UAS
>> at least when the drivers are plugged into the USB3 / superspeed
>> ports of the Pi.  This might still be a too big hammer though.
>> since with a powered-hub, or with a proper power-supply feeding
>> the Pi 4 (and not using the other ports) UAS might still work
>> and you are now taking away those options from users.
>>
>> But setting the XHCI_BROKEN_STREAMS flag on the Pi 4 and only
>> on the Pi 4 would definitely be closer to acceptable then disabling
>> UAS for, well everyone, because it is causing issues on the Pi.
>>
>> Regards,
>>
>> Hans
> 
> Okay, thanks for your feedback! I'll try to check if some of these
> drives have issues on PCs too and then only use that for a future patch.

Great, thank you. Please also be sure to add a link to forum-discussions /
a github issue in future commits.

Regards,

Hans