Re: [PATCH] Bluetooth: btrtl: Load FW v2 otherwise FW v1 for RTL8852C

[Linux regression tracking (Thorsten Leemhuis)]

On 04.08.23 12:15, Max Chou wrote:
>> -----Original Message-----
>> [CCing the linux-firmware maintainer, the network maintainers, and the
>> regressions lists]
>>
>> On 04.08.23 07:54, max.chou@xxxxxxxxxxx wrote:
>>> From: Max Chou <max.chou@xxxxxxxxxxx>
>>>
>>> In the commit of linux-firmware project, rtl8852cu_fw.bin is updated
>>> as FW v2 format[1]. Consider the case that if driver did not be updated fo>
>> FW v2 supported[2], it can not use FW v2.
>>>
>>> By Canonical's suggestion, older driver should be able to load FW v1,
>>
>> Well, that's not only Canonical suggestion, that is how things are supposed to
>> be handled in general. See
>> Documentation/driver-api/firmware/firmware-usage-guidelines.rst (alt:
>> https://docs.kernel.org/driver-api/firmware/firmware-usage-guidelines.html
>> ) for details.
>>
>> We had a similar situation in March already with a Wifi driver:
>> https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/c
>> ommit/?id=416a66cae796939d7d096988c72c641656c81c5a
>>
>> Makes me wonder: is there a problem here we should try harder to avoid?
>> Especially as the problem in this case would have been simple to predict by
>> reading the changelog of the linux-firmware change. To quote from
>> https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/c
>> ommit/?id=55e7448533e7
>>
>> ```
>> Note: This firmware patch needs to be used with driver
>> "btrtl: Firmware format v2 support". Please update the driver with this commit:
>> 9a24ce5e29b15c4c6b0c89c04f9df6ce14addefa
>> ```
> 
> Actually, we thought this note is enough. [...]

Yeah, no big deal, error are made and dealt with, and you are working on
that. Thx for that. It's just that the episode got got me thinking:

It's the second time such error is made within a a few months, hence I
wonder if we on the side of the Linux kernel and/or Linux-firmware
should change something to ideally prevent this from happening.

Ciao, Thorsten