[PATCH v5] spi: Add PPC4xx SPI driver

Stefan Roese sr at denx.de
Tue Jan 6 19:26:34 EST 2009


Hi Wolfgang,

On Monday 05 January 2009, Wolfgang Denk wrote:
> > IIRC (I didn't write the original version of this driver) then this
> > comments simply refers to the fact that the platform can select a maximum
> > SPI frequency via spi->max_speed_hz which is pretty obvious. So I'll just
> > remove this comment in the next version.
>
> On PPC4xx systems we get one interrupt per transferred  byte,  i.  e.
> there  is  a  direct relation between SPI bus frequency and interrupt
> rate.
>
> Since this is a PPC4xx SPI driver, the comment is actually helpful to
> understand the operation of the driver especially in relation to  the
> limitations of the hardware.
>
> Instead of removing the  comment  (which  leaves  the  casual  reader
> clueless)  it  would probably better to add a sentence explaining the
> one byte / one interrupt situation?

OK, I'll this explanation instead.

Thanks.

Best regards,
Stefan



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