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author | Viresh Kumar <viresh.kumar@linaro.org> | 2017-01-02 14:41:03 +0530 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2017-01-27 11:49:09 +0100 |
commit | dc2c9ad52af45ebecf9743aacb1916ebb2f1e848 (patch) | |
tree | 41001b1691bdad8d1b52a63561ffa9659d5412bd | |
parent | 3aa26a3b2ea63c4d09420e74421370655aa1cf8f (diff) | |
download | op-kernel-dev-dc2c9ad52af45ebecf9743aacb1916ebb2f1e848.zip op-kernel-dev-dc2c9ad52af45ebecf9743aacb1916ebb2f1e848.tar.gz |
PM / OPP: Don't expose srcu_head to register notifiers
Let the OPP core provide helpers to register notifiers for any device,
instead of exposing srcu_head outside of the core.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-rw-r--r-- | drivers/base/power/opp/core.c | 66 | ||||
-rw-r--r-- | drivers/devfreq/devfreq.c | 26 | ||||
-rw-r--r-- | include/linux/pm_opp.h | 14 |
3 files changed, 62 insertions, 44 deletions
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 614d779..f35effa 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -1860,29 +1860,63 @@ int dev_pm_opp_disable(struct device *dev, unsigned long freq) EXPORT_SYMBOL_GPL(dev_pm_opp_disable); /** - * dev_pm_opp_get_notifier() - find notifier_head of the device with opp - * @dev: device pointer used to lookup OPP table. + * dev_pm_opp_register_notifier() - Register OPP notifier for the device + * @dev: Device for which notifier needs to be registered + * @nb: Notifier block to be registered * - * Return: pointer to notifier head if found, otherwise -ENODEV or - * -EINVAL based on type of error casted as pointer. value must be checked - * with IS_ERR to determine valid pointer or error result. + * Return: 0 on success or a negative error value. + */ +int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb) +{ + struct opp_table *opp_table; + int ret; + + rcu_read_lock(); + + opp_table = _find_opp_table(dev); + if (IS_ERR(opp_table)) { + ret = PTR_ERR(opp_table); + goto unlock; + } + + ret = srcu_notifier_chain_register(&opp_table->srcu_head, nb); + +unlock: + rcu_read_unlock(); + + return ret; +} +EXPORT_SYMBOL(dev_pm_opp_register_notifier); + +/** + * dev_pm_opp_unregister_notifier() - Unregister OPP notifier for the device + * @dev: Device for which notifier needs to be unregistered + * @nb: Notifier block to be unregistered * - * Locking: This function must be called under rcu_read_lock(). opp_table is a - * RCU protected pointer. The reason for the same is that the opp pointer which - * is returned will remain valid for use with opp_get_{voltage, freq} only while - * under the locked area. The pointer returned must be used prior to unlocking - * with rcu_read_unlock() to maintain the integrity of the pointer. + * Return: 0 on success or a negative error value. */ -struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev) +int dev_pm_opp_unregister_notifier(struct device *dev, + struct notifier_block *nb) { - struct opp_table *opp_table = _find_opp_table(dev); + struct opp_table *opp_table; + int ret; - if (IS_ERR(opp_table)) - return ERR_CAST(opp_table); /* matching type */ + rcu_read_lock(); + + opp_table = _find_opp_table(dev); + if (IS_ERR(opp_table)) { + ret = PTR_ERR(opp_table); + goto unlock; + } + + ret = srcu_notifier_chain_unregister(&opp_table->srcu_head, nb); - return &opp_table->srcu_head; +unlock: + rcu_read_unlock(); + + return ret; } -EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier); +EXPORT_SYMBOL(dev_pm_opp_unregister_notifier); /* * Free OPPs either created using static entries present in DT or even the diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 47206a2..a545c0f 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -1265,18 +1265,7 @@ EXPORT_SYMBOL(devfreq_recommended_opp); */ int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) { - struct srcu_notifier_head *nh; - int ret = 0; - - rcu_read_lock(); - nh = dev_pm_opp_get_notifier(dev); - if (IS_ERR(nh)) - ret = PTR_ERR(nh); - rcu_read_unlock(); - if (!ret) - ret = srcu_notifier_chain_register(nh, &devfreq->nb); - - return ret; + return dev_pm_opp_register_notifier(dev, &devfreq->nb); } EXPORT_SYMBOL(devfreq_register_opp_notifier); @@ -1292,18 +1281,7 @@ EXPORT_SYMBOL(devfreq_register_opp_notifier); */ int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) { - struct srcu_notifier_head *nh; - int ret = 0; - - rcu_read_lock(); - nh = dev_pm_opp_get_notifier(dev); - if (IS_ERR(nh)) - ret = PTR_ERR(nh); - rcu_read_unlock(); - if (!ret) - ret = srcu_notifier_chain_unregister(nh, &devfreq->nb); - - return ret; + return dev_pm_opp_unregister_notifier(dev, &devfreq->nb); } EXPORT_SYMBOL(devfreq_unregister_opp_notifier); diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 7483ff2..66a02de 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -108,7 +108,9 @@ int dev_pm_opp_enable(struct device *dev, unsigned long freq); int dev_pm_opp_disable(struct device *dev, unsigned long freq); -struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev); +int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb); +int dev_pm_opp_unregister_notifier(struct device *dev, struct notifier_block *nb); + int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, unsigned int count); void dev_pm_opp_put_supported_hw(struct device *dev); @@ -202,10 +204,14 @@ static inline int dev_pm_opp_disable(struct device *dev, unsigned long freq) return 0; } -static inline struct srcu_notifier_head *dev_pm_opp_get_notifier( - struct device *dev) +static inline int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb) { - return ERR_PTR(-ENOTSUPP); + return -ENOTSUPP; +} + +static inline int dev_pm_opp_unregister_notifier(struct device *dev, struct notifier_block *nb) +{ + return -ENOTSUPP; } static inline int dev_pm_opp_set_supported_hw(struct device *dev, |