Re: [PATCH Part2 v6 12/49] crypto: ccp: Add support to initialize the AMD-SP for SEV-SNP

[Kalra, Ashish]

Another follow up:

> > >   int sev_platform_init(int *error);
> > > +/**
> > > + * sev_snp_init - perform SEV SNP_INIT command
> > > + *
> > > + * @error: SEV command return code
> > > + *
> > > + * Returns:
> > > + * 0 if the SEV successfully processed the command
> > > + * -%ENODEV    if the SEV device is not available
> > > + * -%ENOTSUPP  if the SEV does not support SEV
> > > + * -%ETIMEDOUT if the SEV command timed out
> > > + * -%EIO       if the SEV returned a non-zero return code
> >
> > Something's weird with those args. I think it should be
> >
> >     %-ENODEV
> >
> > and so on...
>
> Yes, off course %-<errno>

I see that other drivers are also using the same convention:

include/linux/regset.h:
..
/**
 * user_regset_set_fn - type of @set function in &struct user_regset
 * @target:     thread being examined
 * @regset:     regset being examined
 * @pos:        offset into the regset data to access, in bytes
 * @count:      amount of data to copy, in bytes
 * @kbuf:       if not %NULL, a kernel-space pointer to copy from
 * @ubuf:       if @kbuf is %NULL, a user-space pointer to copy from
 *
 * Store register values.  Return %0 on success; -%EIO or -%ENODEV
 * are usual failure returns.  The @pos and @count values are in
...

include/linux/psp-tee.h:
..
/**
 * psp_tee_process_cmd() - Process command in Trusted Execution Environment
 * @cmd_id:     TEE command ID (&enum tee_cmd_id)
 * @buf:        Command buffer for TEE processing. On success, is updated
 *              with the response
 * @len:        Length of command buffer in bytes
 * @status:     On success, holds the TEE command execution status
 *
 * This function submits a command to the Trusted OS for processing in the
 * TEE environment and waits for a response or until the command times out.
 *
 * Returns:
 * 0 if TEE successfully processed the command
 * -%ENODEV    if PSP device not available
 * -%EINVAL    if invalid input
 * -%ETIMEDOUT if TEE command timed out
 * -%EBUSY     if PSP device is not responsive
 */
...

Thanks,
Ashish