>On Wed, May 08, 2013 at 04:34:43PM +0200, Arnd Bergmann wrote:
> > > +#define ASC_MAJOR 204
> > > +#define ASC_MINOR_START 40
> >
> > I don't know what the current policy is on allocating major/minor
> > numbers, but I'm sure you cannot just reuse one that is already used.
>
> First, our apologies, this issue was raised internally and then got forgotten about, there's always something I guess.
>
> > >I agree, why are you trying to create a new tty device name? Can't
> > >you use the existing ttyS name and minor number as you will not have any other type of serial device on this system?
>
> That is an interesting question Greg; I believe it probably stems from historic ST SoCs that had two different types of serial devices,
> something that is no longer the case. We will review our approach to this again, although we are not sure we can use the
> existing ttyS major/minor (even if that is an acceptable thing to do) because of the (remote) possibility of someone using
> a standard PCIe attached serial card.
Greg, having looked at this we have concluded that we should just go dynamic, as others have mentioned with udev on a full system
or devtmpfs on a minimal initramfs system there is no reason to use a static major/minor. However the view here is that we
would prefer to keep the unique name, as for example the lantiq driver which is also dynamic does, for the reason previously
mentioned regarding PCIe cards.
Is that acceptable?
Regards,
-stephen
On Fri, May 10, 2013 at 03:50:16PM +0200, Stephen GALLIMORE wrote:
> Greg, having looked at this we have concluded that we should just go
> dynamic, as others have mentioned with udev on a full system or
> devtmpfs on a minimal initramfs system there is no reason to use a
> static major/minor. However the view here is that we would prefer to
> keep the unique name, as for example the lantiq driver which is also
> dynamic does, for the reason previously mentioned regarding PCIe
> cards.
Why do you want your own name?
> Is that acceptable?
I would prefer not to use a new serial port name, as this is only going
to make it harder for me to delete that name in the next year :)
Sorry,
greg k-h