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SubjectRe: [PATCH v4 2/2] spi-atmel: support inter-word delay
Hi,

On 29/01/2019 15:56:31+0100, Jonas Bonn wrote:
> On 29/01/2019 15:27, Nicolas.Ferre@microchip.com wrote:
> > On 29/01/2019 at 09:38, Jonas Bonn wrote:
> > >
> > > + /* DLYBCT adds delays between words. This is useful for slow devices
> > > + * that need a bit of time to setup the next transfer.
> > > + */
> > > + if (spi->word_delay_us) {
> >
> > Well...
> >
> > > + csr |= SPI_BF(DLYBCT,
> > > + clamp_t(u8,
> > > + (as->spi_clk/1000000*spi->word_delay_us)>>5,
> > > + 1, 255));
> >
> > ... why not simplifying to:
> > + 0, 255));
> > and remove the test altogether, after all?
>
> Hmm... that seemed too easy! This started out as something else and looking
> at it now I think even the clamp_t() is unnecessary. The value is already
> 0-255 and the way SPI_BF works any overflow is already truncated... I'll
> rework this and resubmit once I get some feedback on the word_delay_us bits.
>

While at it, note that you need to add spaces around the operators.

--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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