diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 85 |
1 files changed, 44 insertions, 41 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 1e7e3f2ff09f..c17aa2973c44 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -298,8 +298,10 @@ struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) * EXTERNALLY AFFECTING FREQUENCY CHANGES * *********************************************************************/ -/* - * adjust_jiffies - adjust the system "loops_per_jiffy" +/** + * adjust_jiffies - Adjust the system "loops_per_jiffy". + * @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. + * @ci: Frequency change information. * * This function alters the system "loops_per_jiffy" for the clock * speed change. Note that loops_per_jiffy cannot be updated on SMP @@ -331,14 +333,14 @@ static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) } /** - * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies. + * cpufreq_notify_transition - Notify frequency transition and adjust jiffies. * @policy: cpufreq policy to enable fast frequency switching for. * @freqs: contain details of the frequency update. * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. * - * This function calls the transition notifiers and the "adjust_jiffies" - * function. It is called twice on all CPU frequency changes that have - * external effects. + * This function calls the transition notifiers and adjust_jiffies(). + * + * It is called twice on all CPU frequency changes that have external effects. */ static void cpufreq_notify_transition(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, @@ -1391,8 +1393,10 @@ static int cpufreq_online(unsigned int cpu) policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), GFP_KERNEL); - if (!policy->min_freq_req) + if (!policy->min_freq_req) { + ret = -ENOMEM; goto out_destroy_policy; + } ret = freq_qos_add_request(&policy->constraints, policy->min_freq_req, FREQ_QOS_MIN, @@ -1429,6 +1433,7 @@ static int cpufreq_online(unsigned int cpu) if (cpufreq_driver->get && has_target()) { policy->cur = cpufreq_driver->get(policy->cpu); if (!policy->cur) { + ret = -EIO; pr_err("%s: ->get() failed\n", __func__); goto out_destroy_policy; } @@ -1646,13 +1651,12 @@ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) } /** - * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're - * in deep trouble. - * @policy: policy managing CPUs - * @new_freq: CPU frequency the CPU actually runs at + * cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference. + * @policy: Policy managing CPUs. + * @new_freq: New CPU frequency. * - * We adjust to current frequency first, and need to clean up later. - * So either call to cpufreq_update_policy() or schedule handle_update()). + * Adjust to the current frequency first and clean up later by either calling + * cpufreq_update_policy(), or scheduling handle_update(). */ static void cpufreq_out_of_sync(struct cpufreq_policy *policy, unsigned int new_freq) @@ -1832,7 +1836,7 @@ int cpufreq_generic_suspend(struct cpufreq_policy *policy) EXPORT_SYMBOL(cpufreq_generic_suspend); /** - * cpufreq_suspend() - Suspend CPUFreq governors + * cpufreq_suspend() - Suspend CPUFreq governors. * * Called during system wide Suspend/Hibernate cycles for suspending governors * as some platforms can't change frequency after this point in suspend cycle. @@ -1868,7 +1872,7 @@ suspend: } /** - * cpufreq_resume() - Resume CPUFreq governors + * cpufreq_resume() - Resume CPUFreq governors. * * Called during system wide Suspend/Hibernate cycle for resuming governors that * are suspended with cpufreq_suspend(). @@ -1920,10 +1924,10 @@ bool cpufreq_driver_test_flags(u16 flags) } /** - * cpufreq_get_current_driver - return current driver's name + * cpufreq_get_current_driver - Return the current driver's name. * - * Return the name string of the currently loaded cpufreq driver - * or NULL, if none. + * Return the name string of the currently registered cpufreq driver or NULL if + * none. */ const char *cpufreq_get_current_driver(void) { @@ -1935,10 +1939,10 @@ const char *cpufreq_get_current_driver(void) EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); /** - * cpufreq_get_driver_data - return current driver data + * cpufreq_get_driver_data - Return current driver data. * - * Return the private data of the currently loaded cpufreq - * driver, or NULL if no cpufreq driver is loaded. + * Return the private data of the currently registered cpufreq driver, or NULL + * if no cpufreq driver has been registered. */ void *cpufreq_get_driver_data(void) { @@ -1954,17 +1958,16 @@ EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); *********************************************************************/ /** - * cpufreq_register_notifier - register a driver with cpufreq - * @nb: notifier function to register - * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER + * cpufreq_register_notifier - Register a notifier with cpufreq. + * @nb: notifier function to register. + * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. * - * Add a driver to one of two lists: either a list of drivers that - * are notified about clock rate changes (once before and once after - * the transition), or a list of drivers that are notified about - * changes in cpufreq policy. + * Add a notifier to one of two lists: either a list of notifiers that run on + * clock rate changes (once before and once after every transition), or a list + * of notifiers that ron on cpufreq policy changes. * - * This function may sleep, and has the same return conditions as - * blocking_notifier_chain_register. + * This function may sleep and it has the same return values as + * blocking_notifier_chain_register(). */ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) { @@ -2001,14 +2004,14 @@ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) EXPORT_SYMBOL(cpufreq_register_notifier); /** - * cpufreq_unregister_notifier - unregister a driver with cpufreq - * @nb: notifier block to be unregistered - * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER + * cpufreq_unregister_notifier - Unregister a notifier from cpufreq. + * @nb: notifier block to be unregistered. + * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. * - * Remove a driver from the CPU frequency notifier list. + * Remove a notifier from one of the cpufreq notifier lists. * - * This function may sleep, and has the same return conditions as - * blocking_notifier_chain_unregister. + * This function may sleep and it has the same return values as + * blocking_notifier_chain_unregister(). */ int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) { @@ -2123,7 +2126,7 @@ static int __target_intermediate(struct cpufreq_policy *policy, static int __target_index(struct cpufreq_policy *policy, int index) { struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; - unsigned int intermediate_freq = 0; + unsigned int restore_freq, intermediate_freq = 0; unsigned int newfreq = policy->freq_table[index].frequency; int retval = -EINVAL; bool notify; @@ -2131,6 +2134,9 @@ static int __target_index(struct cpufreq_policy *policy, int index) if (newfreq == policy->cur) return 0; + /* Save last value to restore later on errors */ + restore_freq = policy->cur; + notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); if (notify) { /* Handle switching to intermediate frequency */ @@ -2168,7 +2174,7 @@ static int __target_index(struct cpufreq_policy *policy, int index) */ if (unlikely(retval && intermediate_freq)) { freqs.old = intermediate_freq; - freqs.new = policy->restore_freq; + freqs.new = restore_freq; cpufreq_freq_transition_begin(policy, &freqs); cpufreq_freq_transition_end(policy, &freqs, 0); } @@ -2203,9 +2209,6 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy, !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS)) return 0; - /* Save last value to restore later on errors */ - policy->restore_freq = policy->cur; - if (cpufreq_driver->target) return cpufreq_driver->target(policy, target_freq, relation); |