Some platforms might want to change frequency before suspending governors. Like:
- Some platform which want to set freq to max to speed up suspend/hibernation
  process.
- Some platform (like: Tegra or exynos), set this to min or bootloader's
  frequency.

This patch adds an option for those, so that they can specify this at call to
->init(), so that cpufreq core can take care of this before suspending system.

If this variable is not updated by ->init() then its value would be zero and so
core wouldn't do anything.

Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 drivers/cpufreq/cpufreq.c | 17 +++++++++++++++++
 include/linux/cpufreq.h   |  2 ++
 2 files changed, 19 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 540bd87..e609102 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1476,6 +1476,7 @@ void cpufreq_suspend(void)
 {
        struct cpufreq_policy *policy;
        unsigned long flags;
+       int ret;
 
        if (!has_target())
                return;
@@ -1487,6 +1488,22 @@ void cpufreq_suspend(void)
                        pr_err("%s: Failed to stop governor for policy: %p\n",
                                        __func__, policy);
 
+       /*
+        * In case platform wants some specific frequency to be configured
+        * during suspend
+        */
+       if (policy->suspend_freq) {
+               pr_debug("%s: Suspending Governors: Setting suspend-freq: %u\n",
+                               __func__, policy->suspend_freq);
+
+               ret = __cpufreq_driver_target(policy, policy->suspend_freq,
+                               CPUFREQ_RELATION_H);
+               /* We can still suspend even if this failed */
+               if (ret)
+                       pr_err("%s: Unable to set suspend-freq: %u. Err: %d\n",
+                                       __func__, policy->suspend_freq, ret);
+       }
+
        write_lock_irqsave(&cpufreq_driver_lock, flags);
        cpufreq_suspended = true;
        write_unlock_irqrestore(&cpufreq_driver_lock, flags);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 6d93f91..867fdd4 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -72,6 +72,8 @@ 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;
-- 
1.7.12.rc2.18.g61b472e

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