On Tue, May 24, 2016 at 06:39:20PM +0200, Christer Weinigel wrote: > Document how to use devicetree aliases to assign a stable > bus number to a spi bus. > > Signed-off-by: Christer Weinigel <christer@xxxxxxxxxxx> > > --- > > Trivial documentation change. > > Not having used devicetree that much it was surprisingly hard to > figure out how to assign a stable bus number to a spi bus. Add a > simple example that shows how to do that. > > Mark Cced as the SPI maintainer. Or should trivial documentation > fixes like this be addressed to someone else? > > /Christer > > Documentation/devicetree/bindings/spi/spi-bus.txt | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt > index 42d5954..c35c4c2 100644 > --- a/Documentation/devicetree/bindings/spi/spi-bus.txt > +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt > @@ -94,3 +94,13 @@ SPI example for an MPC5200 SPI bus: > reg = <1>; > }; > }; > + > +Normally SPI buses are assigned dynamic bus numbers starting at 32766 > +and counting downwards. It is possible to assign the bus number > +statically using devicetee aliases. For example, on the MPC5200 the > +"spi@f00" device above is connected to the "soc" bus. To set its > +bus_num to 1 add an aliases entry like this: As Mark Brown pointed out, this is very Linux-specific (at least in the wording of the above). Generally, aliases are there to match _physical_ identifiers (e.g. to match physical labels for UART0, UART1, and on). I'm not sure whether that applies here. Thanks, Mark. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
