cpufreq: move freq change notifications to cpufreq core

Most of the drivers do following in their ->target_index() routines:

	struct cpufreq_freqs freqs;
	freqs.old = old freq...
	freqs.new = new freq...

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);

	/* Change rate here */

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);

This is replicated over all cpufreq drivers today and there doesn't exists a
good enough reason why this shouldn't be moved to cpufreq core instead.

There are few special cases though, like exynos5440, which doesn't do everything
on the call to ->target_index() routine and call some kind of bottom halves for
doing this work, work/tasklet/etc..

They may continue doing notification from their own code as flag:
CPUFREQ_ASYNC_NOTIFICATION is already set for them.

All drivers are also modified in this patch to avoid breaking 'git bisect', as
double notification would happen otherwise.

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 1 insertions, 18 deletions

diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/ppc-corenet-cpufreq.c
index 79d8e9c46b6d..3f7be46d2b27 100644
--- a/drivers/cpufreq/ppc-corenet-cpufreq.c
+++ b/drivers/cpufreq/ppc-corenet-cpufreq.c
@@ -69,8 +69,6 @@ static const struct soc_data sdata[] = {
 static u32 min_cpufreq;
 static const u32 *fmask;
 
-/* serialize frequency changes  */
-static DEFINE_MUTEX(cpufreq_lock);
 static DEFINE_PER_CPU(struct cpu_data *, cpu_data);
 
 /* cpumask in a cluster */
@@ -253,26 +251,11 @@ static int __exit corenet_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 static int corenet_cpufreq_target(struct cpufreq_policy *policy,
 		unsigned int index)
 {
-	struct cpufreq_freqs freqs;
 	struct clk *parent;
-	int ret;
 	struct cpu_data *data = per_cpu(cpu_data, policy->cpu);
 
-	freqs.old = policy->cur;
-	freqs.new = data->table[index].frequency;
-
-	mutex_lock(&cpufreq_lock);
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
-
 	parent = of_clk_get(data->parent, data->table[index].driver_data);
-	ret = clk_set_parent(data->clk, parent);
-	if (ret)
-		freqs.new = freqs.old;
-
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-	mutex_unlock(&cpufreq_lock);
-
-	return ret;
+	return clk_set_parent(data->clk, parent);
 }
 
 static struct cpufreq_driver ppc_corenet_cpufreq_driver = {