| Message ID | 1745622.RpCLJxTa46@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On 10 April 2016 at 09:38, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Since governor operations are generally skipped if cpufreq_suspended > is set, cpufreq_start_governor() should do nothing in that case. > > That function is called in the cpufreq_online() path, and may also > be called from cpufreq_offline() in some cases, which are invoked > by the nonboot CPUs disabing/enabling code during system suspend > to RAM and resume. That happens when all devices have been > suspended, so if the cpufreq driver relies on things like I2C to > get the current frequency, it may not be ready to do that then. > > To prevent problems from happening for this reason, make > cpufreq_update_current_freq(), which is the only function invoked > by cpufreq_start_governor() that doesn't check cpufreq_suspended > already, return 0 upfront if cpufreq_suspended is set. > > Fixes: 3bbf8fe3ae08 (cpufreq: Always update current frequency before startig governor) > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > drivers/cpufreq/cpufreq.c | 3 +++ > 1 file changed, 3 insertions(+) > > Index: linux-pm/drivers/cpufreq/cpufreq.c > =================================================================== > --- linux-pm.orig/drivers/cpufreq/cpufreq.c > +++ linux-pm/drivers/cpufreq/cpufreq.c > @@ -1565,6 +1565,9 @@ static unsigned int cpufreq_update_curre > { > unsigned int new_freq; > > + if (cpufreq_suspended) > + return 0; > + > new_freq = cpufreq_driver->get(policy->cpu); > if (!new_freq) > return 0; Acked-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -1565,6 +1565,9 @@ static unsigned int cpufreq_update_curre { unsigned int new_freq; + if (cpufreq_suspended) + return 0; + new_freq = cpufreq_driver->get(policy->cpu); if (!new_freq) return 0;