On Wed, Oct 15, 2008 at 08:22:28AM -0600, Grant Likely wrote:
> On Wed, Oct 15, 2008 at 03:00:47PM +0200, Wolfgang Ocker wrote:
> > The patch allows to specify that an SPI device needs an active high chip
> > select.
>
> This look reasonable to me. Anyone else have comments on this binding?
Looks good. I'm assuming that a spi controller has its own chip select
machine, since for GPIO chip-select we can pass active-high/low stuff
via gpios = <> property. But well, we can support both ways even for
GPIO chip-selects, I see no problem.
> g.
>
> >
> > Signed-off-by: Wolfgang Ocker <[EMAIL PROTECTED]>
> > ---
> >
> > --- linux-2.6.27-rc7/drivers/of/of_spi.c.of_spi_cshigh 2008-09-22
> > 00:29:55.000000000 +0200
> > +++ linux-2.6.27-rc7/drivers/of/of_spi.c 2008-09-29 13:43:06.000000000
> > +0200
> > @@ -61,6 +61,8 @@
> > spi->mode |= SPI_CPHA;
> > if (of_find_property(nc, "spi-cpol", NULL))
> > spi->mode |= SPI_CPOL;
> > + if (of_find_property(nc, "spi-cs-high", NULL))
> > + spi->mode |= SPI_CS_HIGH;
> >
> > /* Device speed */
> > prop = of_get_property(nc, "spi-max-frequency", &len);
> > ---
> > linux-2.6.27-rc7/Documentation/powerpc/booting-without-of.txt.of_spi_cshigh
> > 2008-09-29 14:14:08.000000000 +0200
> > +++ linux-2.6.27-rc7/Documentation/powerpc/booting-without-of.txt
> > 2008-09-29 14:24:26.000000000 +0200
> > @@ -1917,6 +1917,8 @@
> > inverse clock polarity (CPOL) mode
> > - spi-cpha - (optional) Empty property indicating device
> > requires
> > shifted clock phase (CPHA) mode
> > + - spi-cs-high - (optional) Empty property indicating device
> > requires
> > + chip select active high
> >
> > SPI example for an MPC5200 SPI bus:
> > [EMAIL PROTECTED] {
> >
> >
--
Anton Vorontsov
email: [EMAIL PROTECTED]
irc://irc.freenode.net/bd2
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