[PATCH V6 4/7] cpufreq: Implement cpufreq_generic_suspend()

Viresh Kumar
2014-02-17T09:26:01Z

Multiple platforms need to set CPU to a particular frequency before suspending
system. And so they need a common infrastructure which is provided by this
patch. Those platforms just need to initialize their ->suspend() pointers with
the generic routine.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
drivers/cpufreq/cpufreq.c | 26 ++++++++++++++++++++++++++
include/linux/cpufreq.h | 3 +++
2 files changed, 29 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index c240232..48315e0 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1578,6 +1578,32 @@ static struct subsys_interface cpufreq_interface = {
.remove_dev = cpufreq_remove_dev,
};

+/*
+ * In case platform wants some specific frequency to be configured
+ * during suspend..
+ */
+int cpufreq_generic_suspend(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ if (!policy->suspend_freq) {
+ pr_err("%s: suspend_freq can't be zero\n", __func__);
+ return -EINVAL;
+ }
+
+ pr_debug("%s: Setting suspend-freq: %u\n", __func__,
+ policy->suspend_freq);
+
+ ret = __cpufreq_driver_target(policy, policy->suspend_freq,
+ CPUFREQ_RELATION_H);
+ if (ret)
+ pr_err("%s: unable to set suspend-freq: %u. err: %d\n",
+ __func__, policy->suspend_freq, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL(cpufreq_generic_suspend);
+
/**
* cpufreq_suspend() - Suspend CPUFreq governors
*
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 94ed907..325bab0 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -74,6 +74,8 @@ struct cpufreq_policy {
unsigned int max; /* in kHz */
unsigned int cur; /* in kHz, only needed if cpufreq
* governors are used */
+ unsigned int suspend_freq; /* freq to set during suspend */
+
unsigned int policy; /* see above */
struct cpufreq_governor *governor; /* see below */
void *governor_data;
@@ -299,6 +301,7 @@ cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy)
#ifdef CONFIG_CPU_FREQ
void cpufreq_suspend(void);
void cpufreq_resume(void);
+int cpufreq_generic_suspend(struct cpufreq_policy *policy);
#else
static inline void cpufreq_suspend(void) {}
static inline void cpufreq_resume(void) {}
--
1.7.12.rc2.18.g61b472e