Re: [PATCH v2 04/15] spi: Replace open coded spi_controller_xfer_timeout()

From: Andy Shevchenko
Date: Tue Jul 11 2023 - 11:30:30 EST


On Tue, Jul 11, 2023 at 03:14:54PM +0100, Mark Brown wrote:
> On Tue, Jul 11, 2023 at 02:01:13PM +0300, Andy Shevchenko wrote:
> > On Mon, Jul 10, 2023 at 06:30:32PM +0100, Mark Brown wrote:
> > > On Mon, Jul 10, 2023 at 06:49:21PM +0300, Andy Shevchenko wrote:
>
> > > > + * Assume speed to be 100 kHz if it's not defined at the time of invocation.
>
> > > You didn't mention this bit in the changelog, and I'm not 100% convinced
> > > it was the best idea in the first place. It's going to result in some
> > > very big timeouts if it goes off, and we really should be doing
> > > validation much earlier in the process.
>
> > Okay, let's drop this change.
>
> Like I say we *should* be fine with the refactoring without this, or at
> least if it's an issue we should improve the validation.

For the speeds < 1000 Hz, this change will lead to the div by 0 crash.
It seems that the current code which this one removes is better than
the spi_controller_xfer_timeout() provides.

If anything, the spi_controller_xfer_timeout() should be improved first.
So, for now I drop this for sure. Maybe in the future we can come back
to it.

--
With Best Regards,
Andy Shevchenko