[PATCH 06/62] ARM: davinci: export da8xx_syscfg0_base

Arnd Bergmann
2014-03-20T11:50:44Z

On Thursday 20 March 2014, Sekhar Nori wrote:
> On Thursday 20 March 2014 12:12 PM, Arnd Bergmann wrote:
> > On Thursday 20 March 2014 01:36:13 Sergei Shtylyov wrote:
> >> On 03/19/2014 11:21 PM, Arnd Bergmann wrote:
> >>> The question is whether there is anyone who would do this properly.
> >>
> >> Nobody cares, it seems. As you can imagine, I stopped to care enough after
> >> being switched to other projects.
> >
> > I only care about it because I have the intention to get all 'randconfig'
> > kernels to build eventually. For stuff that is definitely 'legacy'
> > and won't get cleaned up properly, I'm fine with a hack.
> >
> >>> Both the OHCI and MUSB drivers use exactly one register (CFGCHIP2)
> >>
> >> The idea at the time was to just ioremap() this register but I was not
> >> very eager.
> >
> > Yes, that would work, too. However, that would cause problems later
> > if we ever try to make the davinci platform "multiplatform", unless we also
> > pass the physical address in a platform resource and make this a larger
>
> Some SATA driver work done by Bartlomiej Zolnierkiewicz needed driver
> access to syscfg registers too and I just asked him to pass the physical
> addresses using platform resource. I think thats the best bet we have in
> the absence of a modern interface.

Ok.

> > The syscon (system controller) framework helps share a set of registers
> > across multiple drivers. If all accesses to the CFGCHIP2 register are
> > in a single PHY driver, we wouldn't need it.
>
> CFGCHIP2 has controls both for USB 1.1 (OHCI) and USB 2.0 (MUSB). Not
> sure if there can be a single PHY driver for both.

The phy infrastructure explicitly supports multiple consumers for one
phy, if I'm reading the code correctly.

Arnd