cpufreq: Implement cpufreq_generic_suspend()

Multiple platforms need to set CPUs to a particular frequency before
suspending the system, so provide a common infrastructure for them.

Those platforms only need to point their ->suspend callback pointers
to the generic routine.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 289a407a9207..61dd72b8c143 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1567,6 +1567,32 @@ 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
  *