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>

drivers/cpufreq/exynos-cpufreq.c

@@ -25,7 +25,6 @@
 static struct exynos_dvfs_info *exynos_info;
 
 static struct regulator *arm_regulator;
-static struct cpufreq_freqs freqs;
 
 static unsigned int locking_frequency;
 static bool frequency_locked;
@@ -59,18 +58,18 @@ static int exynos_cpufreq_scale(unsigned int target_freq)
 	struct cpufreq_policy *policy = cpufreq_cpu_get(0);
 	unsigned int arm_volt, safe_arm_volt = 0;
 	unsigned int mpll_freq_khz = exynos_info->mpll_freq_khz;
+	unsigned int old_freq;
 	int index, old_index;
 	int ret = 0;
 
-	freqs.old = policy->cur;
-	freqs.new = target_freq;
+	old_freq = policy->cur;
 
 	/*
 	 * The policy max have been changed so that we cannot get proper
 	 * old_index with cpufreq_frequency_table_target(). Thus, ignore
 	 * policy and get the index from the raw freqeuncy table.
 	 */
-	old_index = exynos_cpufreq_get_index(freqs.old);
+	old_index = exynos_cpufreq_get_index(old_freq);
 	if (old_index < 0) {
 		ret = old_index;
 		goto out;
@@ -95,17 +94,14 @@ static int exynos_cpufreq_scale(unsigned int target_freq)
 	}
 	arm_volt = volt_table[index];
 
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
-
 	/* When the new frequency is higher than current frequency */
-	if ((freqs.new > freqs.old) && !safe_arm_volt) {
+	if ((target_freq > old_freq) && !safe_arm_volt) {
 		/* Firstly, voltage up to increase frequency */
 		ret = regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
 		if (ret) {
 			pr_err("%s: failed to set cpu voltage to %d\n",
 				__func__, arm_volt);
-			freqs.new = freqs.old;
-			goto post_notify;
+			return ret;
 		}
 	}
 
@@ -115,22 +111,15 @@ static int exynos_cpufreq_scale(unsigned int target_freq)
 		if (ret) {
 			pr_err("%s: failed to set cpu voltage to %d\n",
 				__func__, safe_arm_volt);
-			freqs.new = freqs.old;
-			goto post_notify;
+			return ret;
 		}
 	}
 
 	exynos_info->set_freq(old_index, index);
 
-post_notify:
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-
-	if (ret)
-		goto out;
-
 	/* When the new frequency is lower than current frequency */
-	if ((freqs.new < freqs.old) ||
-	   ((freqs.new > freqs.old) && safe_arm_volt)) {
+	if ((target_freq < old_freq) ||
+	   ((target_freq > old_freq) && safe_arm_volt)) {
 		/* down the voltage after frequency change */
 		ret = regulator_set_voltage(arm_regulator, arm_volt,
 				arm_volt);
@@ -142,7 +131,6 @@ post_notify:
 	}
 
 out:
-
 	cpufreq_cpu_put(policy);
 
 	return ret;