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>

1 files changed, 12 insertions, 21 deletions

diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index 4dbe7efd86e5..d4585ce2346c 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -37,20 +37,19 @@ static unsigned int cpu0_get_speed(unsigned int cpu)
 
 static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index)
 {
-	struct cpufreq_freqs freqs;
 	struct dev_pm_opp *opp;
 	unsigned long volt = 0, volt_old = 0, tol = 0;
+	unsigned int old_freq, new_freq;
 	long freq_Hz, freq_exact;
 	int ret;
 
 	freq_Hz = clk_round_rate(cpu_clk, freq_table[index].frequency * 1000);
 	if (freq_Hz < 0)
 		freq_Hz = freq_table[index].frequency * 1000;
-	freq_exact = freq_Hz;
-	freqs.new = freq_Hz / 1000;
-	freqs.old = clk_get_rate(cpu_clk) / 1000;
 
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
+	freq_exact = freq_Hz;
+	new_freq = freq_Hz / 1000;
+	old_freq = clk_get_rate(cpu_clk) / 1000;
 
 	if (!IS_ERR(cpu_reg)) {
 		rcu_read_lock();
@@ -58,9 +57,7 @@ static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index)
 		if (IS_ERR(opp)) {
 			rcu_read_unlock();
 			pr_err("failed to find OPP for %ld\n", freq_Hz);
-			freqs.new = freqs.old;
-			ret = PTR_ERR(opp);
-			goto post_notify;
+			return PTR_ERR(opp);
 		}
 		volt = dev_pm_opp_get_voltage(opp);
 		rcu_read_unlock();
@@ -69,16 +66,15 @@ static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index)
 	}
 
 	pr_debug("%u MHz, %ld mV --> %u MHz, %ld mV\n",
-		 freqs.old / 1000, volt_old ? volt_old / 1000 : -1,
-		 freqs.new / 1000, volt ? volt / 1000 : -1);
+		 old_freq / 1000, volt_old ? volt_old / 1000 : -1,
+		 new_freq / 1000, volt ? volt / 1000 : -1);
 
 	/* scaling up?  scale voltage before frequency */
-	if (!IS_ERR(cpu_reg) && freqs.new > freqs.old) {
+	if (!IS_ERR(cpu_reg) && new_freq > old_freq) {
 		ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
 		if (ret) {
 			pr_err("failed to scale voltage up: %d\n", ret);
-			freqs.new = freqs.old;
-			goto post_notify;
+			return ret;
 		}
 	}
 
@@ -87,23 +83,18 @@ static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index)
 		pr_err("failed to set clock rate: %d\n", ret);
 		if (!IS_ERR(cpu_reg))
 			regulator_set_voltage_tol(cpu_reg, volt_old, tol);
-		freqs.new = freqs.old;
-		goto post_notify;
+		return ret;
 	}
 
 	/* scaling down?  scale voltage after frequency */
-	if (!IS_ERR(cpu_reg) && freqs.new < freqs.old) {
+	if (!IS_ERR(cpu_reg) && new_freq < old_freq) {
 		ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
 		if (ret) {
 			pr_err("failed to scale voltage down: %d\n", ret);
-			clk_set_rate(cpu_clk, freqs.old * 1000);
-			freqs.new = freqs.old;
+			clk_set_rate(cpu_clk, old_freq * 1000);
 		}
 	}
 
-post_notify:
-	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
-
 	return ret;
 }