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/s3c64xx-cpufreq.c

@@ -65,54 +65,46 @@ static unsigned int s3c64xx_cpufreq_get_speed(unsigned int cpu)
 static int s3c64xx_cpufreq_set_target(struct cpufreq_policy *policy,
 				      unsigned int index)
 {
-	int ret;
-	struct cpufreq_freqs freqs;
 	struct s3c64xx_dvfs *dvfs;
+	unsigned int old_freq, new_freq;
+	int ret;
 
-	freqs.old = clk_get_rate(armclk) / 1000;
-	freqs.new = s3c64xx_freq_table[index].frequency;
-	freqs.flags = 0;
+	old_freq = clk_get_rate(armclk) / 1000;
+	new_freq = s3c64xx_freq_table[index].frequency;
 	dvfs = &s3c64xx_dvfs_table[s3c64xx_freq_table[index].driver_data];
 
-	pr_debug("Transition %d-%dkHz\n", freqs.old, freqs.new);
-
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
-
 #ifdef CONFIG_REGULATOR
-	if (vddarm && freqs.new > freqs.old) {
+	if (vddarm && new_freq > old_freq) {
 		ret = regulator_set_voltage(vddarm,
 					    dvfs->vddarm_min,
 					    dvfs->vddarm_max);
 		if (ret != 0) {
 			pr_err("Failed to set VDDARM for %dkHz: %d\n",
-			       freqs.new, ret);
-			freqs.new = freqs.old;
-			goto post_notify;
+			       new_freq, ret);
+			return ret;
 		}
 	}
 #endif
 
-	ret = clk_set_rate(armclk, freqs.new * 1000);
+	ret = clk_set_rate(armclk, new_freq * 1000);
 	if (ret < 0) {
 		pr_err("Failed to set rate %dkHz: %d\n",
-		       freqs.new, ret);
-		freqs.new = freqs.old;
+		       new_freq, ret);
+		return ret;
 	}
 
-post_notify:
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-	if (ret)
-		goto err;
-
 #ifdef CONFIG_REGULATOR
-	if (vddarm && freqs.new < freqs.old) {
+	if (vddarm && new_freq < old_freq) {
 		ret = regulator_set_voltage(vddarm,
 					    dvfs->vddarm_min,
 					    dvfs->vddarm_max);
 		if (ret != 0) {
 			pr_err("Failed to set VDDARM for %dkHz: %d\n",
-			       freqs.new, ret);
-			goto err_clk;
+			       new_freq, ret);
+			if (clk_set_rate(armclk, old_freq * 1000) < 0)
+				pr_err("Failed to restore original clock rate\n");
+
+			return ret;
 		}
 	}
 #endif
@@ -121,14 +113,6 @@ post_notify:
 		 clk_get_rate(armclk) / 1000);
 
 	return 0;
-
-err_clk:
-	if (clk_set_rate(armclk, freqs.old * 1000) < 0)
-		pr_err("Failed to restore original clock rate\n");
-err:
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-
-	return ret;
 }
 
 #ifdef CONFIG_REGULATOR