On Wed, Feb 21, 2018 at 6:54 AM, Viresh Kumar <viresh.ku...@linaro.org> wrote: > On 21-02-18, 16:39, Michael Ellerman wrote: >> Viresh Kumar <viresh.ku...@linaro.org> writes: > >> > AFAICT, you will get -1 here only if the freq table had no valid >> > frequencies (or the freq table is empty). Why would that happen ? >> >> Bugs? > > The cupfreq driver shouldn't have registered itself in that case (i.e. > if the cpufreq table is empty).
To be precise, ->init() should fail as that's where the table is created. The registration fails as a result then. But what if the bug is that ->init() doesn't fail when it should? I guess the core could double check the frequency table after ->init() if ->target_index is not NULL. The overall point here is that if you get a negative index in ->fast_switch(), that's way too late anyway and we should be able to catch that error much earlier.
