| Message ID | f1fa8223ab9b9a1183626ec42608ec966a4bc425.1477463128.git.viresh.kumar@linaro.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 10/26, Viresh Kumar wrote: > If the regulators aren't set explicitly by the platform, the OPP core > assumes that the platform doesn't have any regulator and uses the > clk-only callback. > > If the platform failed to register a regulator with the core, then this > can turn out to be a dangerous assumption as the OPP core will try to > change clk without changing regulators. > > Handle that properly by making sure that the DT didn't had any entries s/had/have/ > for supply voltages as well. > > diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c > index 3298fac01bb0..34cd48dfe89e 100644 > --- a/drivers/base/power/opp/core.c > +++ b/drivers/base/power/opp/core.c > @@ -734,7 +734,17 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) > > /* Only frequency scaling */ > if (!regulators) { > - rcu_read_unlock(); > + /* > + * DT contained supply ratings? Consider platform failed to set > + * regulators. > + */ > + if (unlikely(opp->supplies[0].u_volt)) { > + rcu_read_unlock(); > + dev_err(dev, "%s: Regulator not registered with OPP core\n", > + __func__); > + return -EINVAL; > + } > + Don't we need an rcu_read_unlock() here as well? > return _generic_set_opp_clk_only(dev, clk, old_freq, freq); > } >
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 3298fac01bb0..34cd48dfe89e 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -734,7 +734,17 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) /* Only frequency scaling */ if (!regulators) { - rcu_read_unlock(); + /* + * DT contained supply ratings? Consider platform failed to set + * regulators. + */ + if (unlikely(opp->supplies[0].u_volt)) { + rcu_read_unlock(); + dev_err(dev, "%s: Regulator not registered with OPP core\n", + __func__); + return -EINVAL; + } + return _generic_set_opp_clk_only(dev, clk, old_freq, freq); }
If the regulators aren't set explicitly by the platform, the OPP core assumes that the platform doesn't have any regulator and uses the clk-only callback. If the platform failed to register a regulator with the core, then this can turn out to be a dangerous assumption as the OPP core will try to change clk without changing regulators. Handle that properly by making sure that the DT didn't had any entries for supply voltages as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- drivers/base/power/opp/core.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)