Re: [PATCH 0/4] Improve error handling for qnap-mcu transfers

[Lee Jones <lee@kernel.org>]

On Tue, 23 Sep 2025, Heiko Stuebner wrote:

> Digging deeper into how that MCU behaves, I found out it can return
> more status codes than the "@0" for "ok".
> 
> The additional codes can report a failed checksum verification and
> some "general" error for the command execution.
> 
> This also explains sporadic command timeout messages, I have seen
> over time, when the controller sends an error code while we expect
> a longer reply from it.
> 
> So while I'm not sure yet why it reports an error, with these changes
> we at least handle the error return code in a meaningful way.
> 
> 
> Heiko Stuebner (4):
>   mfd: qnap-mcu: Calculate the checksum on the actual number of bytes
>     received
>   mfd: qnap-mcu: Use EPROTO in stead of EIO on checksum errors
>   mfd: qnap-mcu: Move checksum verification to its own function
>   mfd: qnap-mcu: Add proper error handling for command errors
> 
>  drivers/mfd/qnap-mcu.c | 55 +++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 51 insertions(+), 4 deletions(-)

Note to self: patches 1-3 look good.

-- 
Lee Jones [李琼斯]