Re: [RFC] Serial port aliases in DT

[Sascha Hauer <s.hauer@pengutronix.de>]

On Thu, Mar 27, 2014 at 08:54:09AM -0500, Rob Herring wrote:
> >>
> >> > This however comes back to the more general issue of serial port device
> >> > naming: Linux traditionally uses separate names per driver (e.g. ttySC0
> >> > instead of ttyS0).
> >> >
> >> > There has been discussion in the past about changing this to let all
> >> > drivers use the same namespace, but it's not yet clear to me how we'd do
> >> > this in a 100% backwards compatible way. Maybe it's best left to udev to
> >> > figure out the driver independent name, but then we definitely should use
> >> > the alias for that name.
> 
> This discussion has come up in just the last month or so.
> 
> My opinion is device name numbering should start at 0 with 0 being the
> preferred console device.

That's completely different to everything I've heard and seen so far ;)

For specifying the console we have the linux,stdout-path property in the
chosen node. My preferred console may not be a serial port at all in
which case I would end up with a serial0 = &lcd0 alias.  Many
devicetrees specify aliases for i2c/spi/mmc controllers aswell.  Should
they order their i2c controllers in the order of preference now?

Most dtsi files in the kernel specify a SoC specific order of aliases
and I think this makes the most sense.

Sascha

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