On 10-03-20, 16:11, andrew-sh.cheng wrote: > On Tue, 2019-12-10 at 14:43 +0800, Viresh Kumar wrote: > > On 09-12-19, 14:56, andrew-sh.cheng wrote: > > > On Wed, 2019-11-27 at 14:06 +0530, Viresh Kumar wrote: > > > > On 26-11-19, 19:50, Andrew-sh.Cheng wrote: > > > > > + if (!IS_ERR(opp_item)) > > > > > + dev_pm_opp_put(opp_item); > > > > > + else > > > > > + freq = 0; > > > > > + > > > > > > > > What is the purpose of the above code ? > > > When dev_pm_opp_find_freq_ceil() doesn't find matching opp item, freq > > > value won't be set. > > > Set it as 0 for below checking > > > > > > > > > + /* case of current opp is disabled */ > > > > > + if (freq == 0 || freq != info->opp_freq) { > > > > > + // find an enable opp item > > > > > + freq = 1; > > > > > + opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev, > > > > > + &freq); > > > > > + if (!IS_ERR(opp_item)) { > > > > > + dev_pm_opp_put(opp_item); > > > > > + policy = cpufreq_cpu_get(info->opp_cpu); > > > > > + if (policy) { > > > > > + cpufreq_driver_target(policy, > > > > > + freq / 1000, > > > > > + CPUFREQ_RELATION_L); > > > > > > > > Why don't you simply call this instead of all the code in the else > > > > block ? > > > These else code is used to check "current opp item is disabled or not". > > > If not, do nothing. > > > If current opp item is disabled, need to find an not-disabled opp item, > > > and set frequency to it. > > > > Right. So this notifier helper of yours receive the opp which is getting > > disabled, why don't you compare its frequency directly to see if the current OPP > > is getting disabled ? > Sorry to overlook your question. > This is because when the opp is disabled, > we cannot use dev_pm_opp_get_freq() to get frequency of that opp. > There is a check: > if (IS_ERR_OR_NULL(opp) || !opp->available) { I think we can remove the available check here, as we are jut trying to find frequency of an OPP we already have. Send a patch for that please. > pr_err("%s: Invalid parameters\n", __func__); > return 0; > > > > -- viresh