| Message ID | 957838f1065ccc20b0252e0a6d37b61f6b173970.1371630975.git.viresh.kumar@linaro.org |
|---|---|
| State | Accepted |
| Headers | show |
On Wednesday 19 June 2013 04:53 AM, Viresh Kumar wrote: > PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both > should be called or both shouldn't be. > > In case we have started PRECHANGE notifier and found an error, we must call > POSTCHANGE notifier with freqs.new = freqs.old to guarantee that sequence of > calling notifiers is complete. > > Omap driver was taking care of it well, but wasn't restoring freqs.new to > freqs.old in some cases. I wasn't required to add code for it as moving > PRECHANGE notifier down was a better option, so that we call it just before > starting frequency transition. > > Cca: Santosh Shilimkar <santosh.shilimkar@ti.com> > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- Looks safe to me. Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 0279d18..29468a5 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -93,9 +93,6 @@ static int omap_target(struct cpufreq_policy *policy, if (freqs.old == freqs.new && policy->cur == freqs.new) return ret; - /* notifiers */ - cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); - freq = freqs.new * 1000; ret = clk_round_rate(mpu_clk, freq); if (IS_ERR_VALUE(ret)) { @@ -125,6 +122,9 @@ static int omap_target(struct cpufreq_policy *policy, freqs.old / 1000, volt_old ? volt_old / 1000 : -1, freqs.new / 1000, volt ? volt / 1000 : -1); + /* notifiers */ + cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); + /* scaling up? scale voltage before frequency */ if (mpu_reg && (freqs.new > freqs.old)) { r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both should be called or both shouldn't be. In case we have started PRECHANGE notifier and found an error, we must call POSTCHANGE notifier with freqs.new = freqs.old to guarantee that sequence of calling notifiers is complete. Omap driver was taking care of it well, but wasn't restoring freqs.new to freqs.old in some cases. I wasn't required to add code for it as moving PRECHANGE notifier down was a better option, so that we call it just before starting frequency transition. Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- drivers/cpufreq/omap-cpufreq.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)