RE: [PATCH v1] ARM: tegra: add nvidia,wdt-timer-id optional property

[Andrew Chew <AChew@nvidia.com>]

> On 02/03/2014 02:16 PM, Andrew Chew wrote:
> >> On 02/03/2014 11:59 AM, Andrew Chew wrote:
> >>>> On Fri, Jan 31, 2014 at 09:46:51PM +0000, Andrew Chew wrote:
> >>>>> This optional property can be used to specify which timers are to
> >>>>> be used for hardware watchdog timeouts (via a tegra wdt driver).
> >>>>
> >>>> Is there any reason that a particular timer should be used?
> >>>
> >>> I worry about colliding with other timer allocations, and wanted to
> >>> be flexible in this regard.
> >>
> >> Are the other timer allocations represented in DT, or simply made by
> >> or hard- coded in the driver? If the former, this property seems like
> >> a good equivalent of any existing allocations. If the latter, can't
> >> the driver just allocate or hard- code the allocation in the same way as any
> existing allocations?
> >
> > From what I've seen, timer allocations are just hard-coded into whatever
> driver.
> > I didn't think this was a particularly good idea, since when writing
> > other drivers that for some reason need a timer, the author has to be
> > aware of allocations made in other, barely related drivers.
> 
> I'm not sure that they would; why wouldn't the timer driver register the
> various timers with standard Linux APIs which the clients talk to, thus
> avoiding the clients having any knowledge at all of which channels are used
> for what.
> 
> If you're talking about the watchdog driver, then can't we just create a
> shared header file that the clocksource and watchdog drivers both include,
> which defines the timer ID allocations?

Sure, let's go with that.  In that case, this patch isn't needed, and should be
dropped.