On Tue, 2018-07-17 at 14:40 +0000, Phil Edworthy wrote:
> Hi Andy,
>
> On 17 July 2018 15:19, Andy Shevchenko wrote:
> > On Tue, 2018-07-17 at 12:42 +0000, Phil Edworthy wrote:
> >
> > > > While your point sounds valid (don't remember how clk_get() is
> > > > implemented), NULL is also OK to have.
> > >
> > > Ok as in there is no bus clock, right?
> > > So it should be:
> > > if (!IS_ERR_OR_NULL (dev->busclk))
> >
> > Nope, NULL is no error case for optional clock.
>
> I must be missing something here...
See how clk_prepare_enable() is implemented.
> I agree that NULL for an optional clock is not an error. However, the
> code above is now:
> + if (prepare) {
> + /* Optional bus clock */
> + if (!IS_ERR_OR_NULL(dev->busclk)) {
Check for NULL is redundant.
> + ret = clk_prepare_enable(dev->busclk);
> + if (ret)
> + return ret;
> + }
> +
> return clk_prepare_enable(dev->clk);
> + }
>
> So, if you have a valid busclk, it gets enabled, otherwise it is
> left alone.
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
