diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/hwspinlock/hwspinlock_core.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index bea358604bb2..d542b6fbf0f2 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -735,6 +735,116 @@ out: } EXPORT_SYMBOL_GPL(hwspin_lock_free); +static int devm_hwspin_lock_match(struct device *dev, void *res, void *data) +{ + struct hwspinlock **hwlock = res; + + if (WARN_ON(!hwlock || !*hwlock)) + return 0; + + return *hwlock == data; +} + +static void devm_hwspin_lock_release(struct device *dev, void *res) +{ + hwspin_lock_free(*(struct hwspinlock **)res); +} + +/** + * devm_hwspin_lock_free() - free a specific hwspinlock for a managed device + * @dev: the device to free the specific hwspinlock + * @hwlock: the specific hwspinlock to free + * + * This function mark @hwlock as free again. + * Should only be called with an @hwlock that was retrieved from + * an earlier call to hwspin_lock_request{_specific}. + * + * Should be called from a process context (might sleep) + * + * Returns 0 on success, or an appropriate error code on failure + */ +int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock) +{ + int ret; + + ret = devres_release(dev, devm_hwspin_lock_release, + devm_hwspin_lock_match, hwlock); + WARN_ON(ret); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_hwspin_lock_free); + +/** + * devm_hwspin_lock_request() - request an hwspinlock for a managed device + * @dev: the device to request an hwspinlock + * + * This function should be called by users of the hwspinlock device, + * in order to dynamically assign them an unused hwspinlock. + * Usually the user of this lock will then have to communicate the lock's id + * to the remote core before it can be used for synchronization (to get the + * id of a given hwlock, use hwspin_lock_get_id()). + * + * Should be called from a process context (might sleep) + * + * Returns the address of the assigned hwspinlock, or NULL on error + */ +struct hwspinlock *devm_hwspin_lock_request(struct device *dev) +{ + struct hwspinlock **ptr, *hwlock; + + ptr = devres_alloc(devm_hwspin_lock_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + hwlock = hwspin_lock_request(); + if (!IS_ERR(hwlock)) { + *ptr = hwlock; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return hwlock; +} +EXPORT_SYMBOL_GPL(devm_hwspin_lock_request); + +/** + * devm_hwspin_lock_request_specific() - request for a specific hwspinlock for + * a managed device + * @dev: the device to request the specific hwspinlock + * @id: index of the specific hwspinlock that is requested + * + * This function should be called by users of the hwspinlock module, + * in order to assign them a specific hwspinlock. + * Usually early board code will be calling this function in order to + * reserve specific hwspinlock ids for predefined purposes. + * + * Should be called from a process context (might sleep) + * + * Returns the address of the assigned hwspinlock, or NULL on error + */ +struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev, + unsigned int id) +{ + struct hwspinlock **ptr, *hwlock; + + ptr = devres_alloc(devm_hwspin_lock_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + hwlock = hwspin_lock_request_specific(id); + if (!IS_ERR(hwlock)) { + *ptr = hwlock; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return hwlock; +} +EXPORT_SYMBOL_GPL(devm_hwspin_lock_request_specific); + MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Hardware spinlock interface"); MODULE_AUTHOR("Ohad Ben-Cohen <ohad@wizery.com>"); |