Re: [PATCH 1/6 v2] arm: use devicetree to get smp_twd clock

Russell King - ARM Linux
2012-11-05T22:31:55Z

On Mon, Nov 05, 2012 at 04:28:05PM -0600, Mark Langsdorf wrote:
> On 11/04/2012 04:08 AM, Russell King - ARM Linux wrote:
> > On Fri, Nov 02, 2012 at 01:51:44PM -0500, Mark Langsdorf wrote:
> >> -static struct clk *twd_get_clock(void)
> >> +static struct clk *twd_get_clock(struct device_node *np)
> >> {
> >> - struct clk *clk;
> >> + struct clk *clk = NULL;
> >> int err;
> >>
> >> - clk = clk_get_sys("smp_twd", NULL);
> >> + if (np)
> >> + clk = of_clk_get(np, 0);
> >> + if (!clk)
> >
> > What does a NULL return from of_clk_get() mean? Where is this defined?
>
> Well, it's a valid path if (np) is NULL. I'll add an IS_ERR(clk) and
> resubmit.

Hang on - what logic are you trying to achieve here? Wouldn't:

if (np)
clk = of_clk_get(np, 0);
else
clk = clk_get_sys("smp_twd", NULL);

be sufficient? If we have DT, why would we ever want to fall back to
"smp_twd" ?