[PATCH] cpufreq: cpufreq-cpu0: No need to check cpu number in init()

[PATCH] cpufreq: cpufreq-cpu0: No need to check cpu number in init()

[Viresh Kumar]

It is not possible for init() to be called for any cpu other than cpu0. During
bootup whatever cpu is used to boot system will be assigned as cpu0. And later
on policy->cpu can only change if we hotunplug all cpus first and then hotplug
them back in different order, which isn't possible (system requires atleast one
cpu to be up always :)).

Though I can see one situation where policy->cpu can be different then zero.
- Hot-unplug cpu 0.
- rmmod cpufreq-cpu0 module
- insmod it back
- hotplug cpu 0 again.

Here, policy->cpu would be different. But the driver doesn't have any dependency
on cpu0 as such. We don't mind which cpu of a system is policy->cpu and so this
check is just not required.

Remove it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/cpufreq/cpufreq-cpu0.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index 0f16267..1cab820 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -124,9 +124,6 @@ static int cpu0_cpufreq_init(struct cpufreq_policy *policy)
 {
 	int ret;
 
-	if (policy->cpu != 0)
-		return -EINVAL;
-
 	ret = cpufreq_frequency_table_cpuinfo(policy, freq_table);
 	if (ret) {
 		pr_err("invalid frequency table: %d\n", ret);
-- 
1.7.12.rc2.18.g61b472e

Re: [PATCH] cpufreq: cpufreq-cpu0: No need to check cpu number in init()

[Shawn Guo]

On Sat, Mar 30, 2013 at 06:26:29PM +0530, Viresh Kumar wrote:
> It is not possible for init() to be called for any cpu other than cpu0. During
> bootup whatever cpu is used to boot system will be assigned as cpu0. And later
> on policy->cpu can only change if we hotunplug all cpus first and then hotplug
> them back in different order, which isn't possible (system requires atleast one
> cpu to be up always :)).
> 
> Though I can see one situation where policy->cpu can be different then zero.
> - Hot-unplug cpu 0.
> - rmmod cpufreq-cpu0 module
> - insmod it back
> - hotplug cpu 0 again.
> 
> Here, policy->cpu would be different. But the driver doesn't have any dependency
> on cpu0 as such. We don't mind which cpu of a system is policy->cpu and so this
> check is just not required.
> 
> Remove it.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Acked-by: Shawn Guo <shawn.guo@linaro.org>