Re: [PATCH] gpu: host1x: clk_round_rate() can return a zero uponerror

[Paul Walmsley]

On 12/10/2013 11:51 PM, Sascha Hauer wrote:
> On Mon, Dec 09, 2013 at 06:00:12PM -0800, Paul Walmsley wrote:
> > Treat both negative and zero return values from clk_round_rate() as
> > errors.  This is needed since subsequent patches will convert
> > clk_round_rate()'s return value to be an unsigned type, rather than a
> > signed type, since some clock sources can generate rates higher than
> > (2^31)-1 Hz.
> >
> > Eventually, when calling clk_round_rate(), only a return value of zero
> > will be considered a error.  All other values will be considered valid
> > rates.  The comparison against values less than 0 is kept to preserve
> > the correct behavior in the meantime.
> Shouldn't it be an error when the result is not within sensible limits
> instead? What do you do with a rate of 1Hz?

It's up to the caller of clk_round_rate() to decide what doesn't make 
sense for its use-case.  The caller can certainly react to non-zero 
rates as it likes.

The 0 return code (and the previous negative return values that were 
used previously) are just intended for the clock framework to signal 
explicit errors encountered during clk_round_rate()'s execution.

- Paul
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/