diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r-- | drivers/cpufreq/cpufreq.c | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 2ce3de5e84af..5e626b12b97e 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -763,6 +763,8 @@ static int cpufreq_add_dev (struct sys_device * sys_dev) init_completion(&policy->kobj_unregister); INIT_WORK(&policy->update, handle_update); + /* Set governor before ->init, so that driver could check it */ + policy->governor = CPUFREQ_DEFAULT_GOVERNOR; /* call driver. From then on the cpufreq must be able * to accept all calls to ->verify and ->setpolicy for this CPU */ @@ -1109,12 +1111,7 @@ unsigned int cpufreq_quick_get(unsigned int cpu) unsigned int ret_freq = 0; if (policy) { - if (unlikely(lock_policy_rwsem_read(cpu))) - return ret_freq; - ret_freq = policy->cur; - - unlock_policy_rwsem_read(cpu); cpufreq_cpu_put(policy); } @@ -1483,6 +1480,31 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, { int ret; + /* Only must be defined when default governor is known to have latency + restrictions, like e.g. conservative or ondemand. + That this is the case is already ensured in Kconfig + */ +#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE + struct cpufreq_governor *gov = &cpufreq_gov_performance; +#else + struct cpufreq_governor *gov = NULL; +#endif + + if (policy->governor->max_transition_latency && + policy->cpuinfo.transition_latency > + policy->governor->max_transition_latency) { + if (!gov) + return -EINVAL; + else { + printk(KERN_WARNING "%s governor failed, too long" + " transition latency of HW, fallback" + " to %s governor\n", + policy->governor->name, + gov->name); + policy->governor = gov; + } + } + if (!try_module_get(policy->governor->owner)) return -EINVAL; @@ -1703,7 +1725,7 @@ int cpufreq_update_policy(unsigned int cpu) } EXPORT_SYMBOL(cpufreq_update_policy); -static int cpufreq_cpu_callback(struct notifier_block *nfb, +static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; |