Messages in this thread |  | | Subject | Re: [PATCH] PM / devfreq: Add missing function description and rename static functions | From | Chanwoo Choi <> | Date | Wed, 8 Jan 2020 17:48:39 +0900 |
| |
On 1/8/20 2:03 PM, Chanwoo Choi wrote: > On 1/7/20 10:35 AM, Chanwoo Choi wrote: >> Rename internal function name used by devfreq core without 'devfreq_' >> prefix in order to separate them from the exported functions. >> And add missing function description for improving the readability. >> >> Lastly, add the comments of devfreq_add_device to increase >> the understanding of behavior of devfreq_add_device. >> >> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> >> --- >> drivers/devfreq/devfreq.c | 81 +++++++++++++++++++++++++++++++-------- >> 1 file changed, 64 insertions(+), 17 deletions(-) >> >> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c >> index acd21345a070..254f11b31824 100644 >> --- a/drivers/devfreq/devfreq.c >> +++ b/drivers/devfreq/devfreq.c >> @@ -48,7 +48,7 @@ static LIST_HEAD(devfreq_list); >> static DEFINE_MUTEX(devfreq_list_lock); >> >> /** >> - * find_device_devfreq() - find devfreq struct using device pointer >> + * find_device_devfreq() - Find devfreq struct using device pointer >> * @dev: device pointer used to lookup device devfreq. >> * >> * Search the list of device devfreqs and return the matched device's >> @@ -73,6 +73,13 @@ static struct devfreq *find_device_devfreq(struct device *dev) >> return ERR_PTR(-ENODEV); >> } >> >> +/** >> + * find_available_min_freq() - Find available min frequency via OPP interface >> + * @devfreq: the devfreq instance >> + * >> + * Find available minimum frequency among the active OPP entries >> + * because could either enable or disable the frequency by using OPP interface. >> + */ >> static unsigned long find_available_min_freq(struct devfreq *devfreq) >> { >> struct dev_pm_opp *opp; >> @@ -87,6 +94,13 @@ static unsigned long find_available_min_freq(struct devfreq *devfreq) >> return min_freq; >> } >> >> +/** >> + * find_available_max_freq() - Find available max frequency via OPP interface >> + * @devfreq: the devfreq instance >> + * >> + * Find available maximum frequency among the active OPP entries >> + * because could either enable or disable the frequency by using OPP interface. >> + */ >> static unsigned long find_available_max_freq(struct devfreq *devfreq) >> { >> struct dev_pm_opp *opp; >> @@ -150,11 +164,11 @@ static void get_freq_range(struct devfreq *devfreq, >> } >> >> /** >> - * devfreq_get_freq_level() - Lookup freq_table for the frequency >> + * get_freq_level() - Lookup freq_table for the frequency >> * @devfreq: the devfreq instance >> * @freq: the target frequency >> */ >> -static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) >> +static int get_freq_level(struct devfreq *devfreq, unsigned long freq) >> { >> int lev; >> >> @@ -165,6 +179,13 @@ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) >> return -EINVAL; >> } >> >> +/** >> + * set_freq_table() - Fill out the freq_table of devfreq instance >> + * @devfreq: the devfreq instance >> + * >> + * If freq_table array is NULL, fill out the freq_table array >> + * by using OPP interface because OPP is mandatory. >> + */ >> static int set_freq_table(struct devfreq *devfreq) >> { >> struct devfreq_dev_profile *profile = devfreq->profile; >> @@ -218,7 +239,7 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >> if (!devfreq->previous_freq) >> goto out; >> >> - prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq); >> + prev_lev = get_freq_level(devfreq, devfreq->previous_freq); >> if (prev_lev < 0) { >> ret = prev_lev; >> goto out; >> @@ -227,7 +248,7 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >> devfreq->stats.time_in_state[prev_lev] += >> cur_time - devfreq->stats.last_update; >> >> - lev = devfreq_get_freq_level(devfreq, freq); >> + lev = get_freq_level(devfreq, freq); >> if (lev < 0) { >> ret = lev; >> goto out; >> @@ -246,7 +267,7 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) >> EXPORT_SYMBOL(devfreq_update_status); >> >> /** >> - * find_devfreq_governor() - find devfreq governor from name >> + * find_devfreq_governor() - Find devfreq governor from name >> * @name: name of the governor >> * >> * Search the list of devfreq governors and return the matched >> @@ -314,8 +335,17 @@ static struct devfreq_governor *try_then_request_governor(const char *name) >> return governor; >> } >> >> -static int devfreq_notify_transition(struct devfreq *devfreq, >> - struct devfreq_freqs *freqs, unsigned int state) >> +/** >> + * notify_transition() - Send the transition notification >> + * @name: name of the governor >> + * @freqs: the data containing the both old and new frequency >> + * @state: the kind of notification >> + * >> + * Send the transition notification to the registered receivers >> + * in order to inform the frequency change. >> + */ >> +static int notify_transition(struct devfreq *devfreq, >> + struct devfreq_freqs *freqs, unsigned int state) >> { >> if (!devfreq) >> return -EINVAL; >> @@ -337,8 +367,17 @@ static int devfreq_notify_transition(struct devfreq *devfreq, >> return 0; >> } >> >> -static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, >> - u32 flags) >> +/** >> + * set_target() - Set target frequency of devfreq instance >> + * @devfreq: the devfreq instance >> + * @new_freq: the target frequency >> + * @flags: flags handed from devfreq framework >> + * >> + * Set the target frequency of which is decided by governor >> + * and then is adjusted with constraints. >> + */ >> +static int set_target(struct devfreq *devfreq, >> + unsigned long new_freq, u32 flags) >> { >> struct devfreq_freqs freqs; >> unsigned long cur_freq; >> @@ -351,17 +390,17 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, >> >> freqs.old = cur_freq; >> freqs.new = new_freq; >> - devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); >> + notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); >> >> err = devfreq->profile->target(devfreq->dev.parent, &new_freq, flags); >> if (err) { >> freqs.new = cur_freq; >> - devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); >> + notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); >> return err; >> } >> >> freqs.new = new_freq; >> - devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); >> + notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); >> >> if (devfreq_update_status(devfreq, new_freq)) >> dev_err(&devfreq->dev, >> @@ -413,7 +452,7 @@ int update_devfreq(struct devfreq *devfreq) >> flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ >> } >> >> - return devfreq_set_target(devfreq, freq, flags); >> + return set_target(devfreq, freq, flags); >> >> } >> EXPORT_SYMBOL(update_devfreq); >> @@ -421,7 +460,6 @@ EXPORT_SYMBOL(update_devfreq); >> /** >> * devfreq_monitor() - Periodically poll devfreq objects. >> * @work: the work struct used to run devfreq_monitor periodically. >> - * >> */ >> static void devfreq_monitor(struct work_struct *work) >> { >> @@ -739,11 +777,13 @@ struct devfreq *devfreq_add_device(struct device *dev, >> static atomic_t devfreq_no = ATOMIC_INIT(-1); >> int err = 0; >> >> + /* Check the parameter is valid */ >> if (!dev || !profile || !governor_name) { >> dev_err(dev, "%s: Invalid parameters.\n", __func__); >> return ERR_PTR(-EINVAL); >> } >> >> + /* Check the device is already added or not */ >> mutex_lock(&devfreq_list_lock); >> devfreq = find_device_devfreq(dev); >> mutex_unlock(&devfreq_list_lock); >> @@ -754,6 +794,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >> goto err_out; >> } >> >> + /* Initialize the devfreq instance */ >> devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); >> if (!devfreq) { >> err = -ENOMEM; >> @@ -798,6 +839,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >> devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); >> atomic_set(&devfreq->suspend_count, 0); >> >> + /* Register a device for devfreq instance */ >> dev_set_name(&devfreq->dev, "devfreq%d", >> atomic_inc_return(&devfreq_no)); >> err = device_register(&devfreq->dev); >> @@ -807,6 +849,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >> goto err_out; >> } >> >> + /* Initialize the statistics of devfreq device behavior */ >> devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev, >> array3_size(sizeof(unsigned int), >> devfreq->profile->max_state, >> @@ -831,10 +874,12 @@ struct devfreq *devfreq_add_device(struct device *dev, >> devfreq->stats.total_trans = 0; >> devfreq->stats.last_update = get_jiffies_64(); >> >> + /* Initialize notifiers for informing the transition of devfreq */ >> srcu_init_notifier_head(&devfreq->transition_notifier_list); >> >> mutex_unlock(&devfreq->lock); >> >> + /* Initialize PM QoS for applying the constraints */ >> err = dev_pm_qos_add_request(dev, &devfreq->user_min_freq_req, >> DEV_PM_QOS_MIN_FREQUENCY, 0); >> if (err < 0) >> @@ -859,6 +904,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >> >> mutex_lock(&devfreq_list_lock); >> >> + /* Find the devfreq governor and start */ >> governor = try_then_request_governor(devfreq->governor_name); >> if (IS_ERR(governor)) { >> dev_err(dev, "%s: Unable to find governor for the device\n", >> @@ -876,6 +922,7 @@ struct devfreq *devfreq_add_device(struct device *dev, >> goto err_init; >> } >> >> + /* Add the devfreq instance to global devfreq list finally */ >> list_add(&devfreq->node, &devfreq_list); >> >> mutex_unlock(&devfreq_list_lock); >> @@ -1076,7 +1123,7 @@ int devfreq_suspend_device(struct devfreq *devfreq) >> >> if (devfreq->suspend_freq) { >> mutex_lock(&devfreq->lock); >> - ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0); >> + ret = set_target(devfreq, devfreq->suspend_freq, 0); >> mutex_unlock(&devfreq->lock); >> if (ret) >> return ret; >> @@ -1106,7 +1153,7 @@ int devfreq_resume_device(struct devfreq *devfreq) >> >> if (devfreq->resume_freq) { >> mutex_lock(&devfreq->lock); >> - ret = devfreq_set_target(devfreq, devfreq->resume_freq, 0); >> + ret = set_target(devfreq, devfreq->resume_freq, 0); >> mutex_unlock(&devfreq->lock); >> if (ret) >> return ret; >> > > Applied it. >
I'm sorry. Drop this patch because it is not enough to add the missing description for functions. I'll add the more description and then resend it.
-- Best Regards, Chanwoo Choi Samsung Electronics
|  |