Re: [PATCH 07/12] spi: Do spi_take_timestamp_pre for as many times as necessary

[Vladimir Oltean]

Hi Mark,

On Thu, 5 Mar 2020 at 14:12, Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> On Thu, Mar 05, 2020 at 12:00:39AM +0200, Vladimir Oltean wrote:
> > From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> >
> > When dealing with a SPI controller driver that is sending more than 1
> > byte at once (or the entire buffer at once), and the SPI peripheral
> > driver has requested timestamping for a byte in the middle of the
> > buffer, we find that spi_take_timestamp_pre never records a "pre"
> > timestamp.
>
> This is a fix and so should have been at the start of the series to make
> sure there aren't any dependencies.

My reasoning for not submitting it as a fix is:
- The only driver that uses the functionality so far - spi-fsl-dspi -
has worked thus far even with the limitation that only byte-by-byte
transfers were supported properly.
- I removed the limitation before actually changing the operating mode
of spi-fsl-dspi. Therefore the limitation is effectively never seen.
- New SPI drivers that would want to make use of software timestamping
would do so through your SPI for-next branch anyway, where the
limitation would be, again, fixed.

Thanks,
-Vladimir