Re: [PATCH 0/2] firmware: stratix10-svc: Fix probe failure with old ATF

[Dinh Nguyen <dinguyen@kernel.org>]

On 4/16/26 02:22, Muhammad Amirul Asyraf Mohamad Jamian wrote:
> Since commit bcb9f4f07061 ("firmware: stratix10-svc: Add support for
> async communication"), the SVC driver fails to probe entirely when
> running with ATF versions older than 3.0 (e.g. ATF 2.5) that do not
> support SIP SVC v3 asynchronous operations.
> 
> stratix10_svc_async_init() returns -EINVAL for old ATF, and the probe
> function treats any non-zero return as fatal, causing:
> 
>    stratix10-svc firmware:svc: probe with driver stratix10-svc failed \
>      with error -22
> 
> This prevents all dependent client drivers (hwmon, RSU, FCS) from
> probing even though they can operate correctly via the synchronous V1
> SMC path.
> 
> This series fixes the issue in two steps:
>    1. Return -EOPNOTSUPP (instead of -EINVAL) when ATF async is
>       unsupported, so callers can distinguish "not supported" from
>       "bad argument / programming error".
>    2. Treat -EOPNOTSUPP as non-fatal in probe, allowing the SVC driver
>       to load in sync-only mode so all client drivers can probe normally.
> 
> Both patches fix bcb9f4f07061 and are tagged for stable.
> 
>
I think it makes more sense to squash these 2 patches together. Patch 1 
adds the -EOPNOTSUPP, but does not make use of it. Patch 2 actually 
makes use of the -EOPNOTSUPP. So I was a bit confused on how the change 
is getting used.

Dinh