Re: [PATCH] usb: uas: ignore UAS for ASMT135x bridges (174c:55aa)

[sashiko-bot@kernel.org]

> The ASMedia chip detection in uas_use_uas_driver() assumes that every
> device with idVendor/idProduct 174c:5106 or 174c:55aa reporting a
> config.MaxPower of 0 is an ASM1153 with working UAS.
> 
> Newer ASMT135x bridges (iProduct "ASMT135x") share the same 174c:55aa
> id and also report MaxPower == 0, so they take the "ASM1153, do
> nothing" path — but their UAS implementation is broken:
> 
> - The first READ(16) issued by sd probing times out after 30 s;
>   enumeration only completes after a uas_eh_abort_handler plus a full
>   uas_eh_host_reset_handler cycle:
> 
>     scsi 3:0:0:0: Direct-Access  ASMT  ASMT135x  0  PQ: 0 ANSI: 6
>     sd 3:0:0:0: [sdb] tag#26 uas_eh_abort_handler 0 uas-tag 1 inflight: CMD IN
>     sd 3:0:0:0: [sdb] tag#26 CDB: Read(16) 88 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00
> [ ... ]
> with the equivalent usb-storage quirks parameter (174c:55aa:u) the
> device is completely stable.
> 
> Reported-by: Olivier Kaloudoff <olivier.kaloudoff@gmail.com>
> Signed-off-by: Olivier Kaloudoff <olivier.kaloudoff@gmail.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261011164259.30572-1-olivier.kaloudoff@gmail.com?part=1