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.
changes in v3:
- fix stupid mistake of not running checkpatch after reorganizing
the error handling code and having the function opening { not
on the next line
changes in v2:
- rebase on top of 6.18-rc1
- include improvement suggestions from Lee
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 | 79 +++++++++++++++++++++++++++++++++++++++---
1 file changed, 74 insertions(+), 5 deletions(-)
--
2.47.2