[PATCH] watchdog: add support for the Synopsys DesignWare WDT

[Jamie Iles]

On Wed, Jan 12, 2011 at 02:27:47PM +0530, viresh kumar wrote:
> Jamie,
> 
> On Wed, Jan 12, 2011 at 1:54 PM, Jamie Iles <jamie at jamieiles.com> wrote:
> >> I don't know why, but checkpatch used to give few errors which it is
> >> not giving now.
> >> Like:
> >> - Mixing spaces and tabs
> >> - Line over 80 columns.
> >>
> >> There are few places in this patch where i have seen these issues, but
> >> checkpatch doesn't
> >> report them at all.
> >
> > Hmm, the only lines over 80 chars are printk lines and I can't see any
> > with mixed spaces and tabs...
> 
> There are few in file drivers/watchdog/dw_wdt.c
> line 40-45, 127, 133, 156, 167, 204, 216, 315, 319.

I do need to fix up the register locations (40-45) but the others are ok 
- they are tab indented to get to a multiple of 8 then spaces to align 
to the '(' brackets etc.

> >> I know it doesn't make sense for a platform to have support for clk framework
> >> and pass rate through plat data. But this code will always take
> >> pdata->rate, if it is passed.
> >> Wouldn't it be better if we reverse the sequence.
> >>
> >> if (clk)
> >>  rate = clk_get_rate(...);
> >> else {
> >>  pdata = pdev->dev.platform_data;
> >>  if (pdata)
> >>   rate = pdata->rate;
> >> }
> >>
> >> and then following code
> >
> > That's what I did first (without the test that clk is not NULL) but
> > switched it the other way round so that the platform can override the
> > frequency by setting platform_data->clk_rate to nonzero.  That just
> > seems a little more flexible and easy for testing but I'm happy to
> > switch the order if you feel that's important.
> >
> 
> Problem will occur if rate is dynamically changed and we are still believing
> on platform code's clk_rate.
> Would be better if we switch order. i.e. give priority to clk_get_rate over
> pdata->rate.

If the platform can change the rate then I don't see why it would define 
the rate in the platform data though.  Anyway, I can make the change and 
issue a warning and fail the probe if we're using the rate from 
clk_get_rate() and there is a non-zero rate in the platform data.

Jamie