diff options
Diffstat (limited to 'include/linux/hwspinlock.h')
| -rw-r--r-- | include/linux/hwspinlock.h | 175 |
1 files changed, 155 insertions, 20 deletions
diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index 3343298e40e8..f35b42e8c5de 100644 --- a/include/linux/hwspinlock.h +++ b/include/linux/hwspinlock.h @@ -1,18 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* * Hardware spinlock public header * * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com * * Contact: Ohad Ben-Cohen <ohad@wizery.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #ifndef __LINUX_HWSPINLOCK_H @@ -22,10 +14,13 @@ #include <linux/sched.h> /* hwspinlock mode argument */ -#define HWLOCK_IRQSTATE 0x01 /* Disable interrupts, save state */ -#define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */ +#define HWLOCK_IRQSTATE 0x01 /* Disable interrupts, save state */ +#define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */ +#define HWLOCK_RAW 0x03 +#define HWLOCK_IN_ATOMIC 0x04 /* Called while in atomic context */ struct device; +struct device_node; struct hwspinlock; struct hwspinlock_device; struct hwspinlock_ops; @@ -58,19 +53,29 @@ struct hwspinlock_pdata { int base_id; }; -#if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE) +#ifdef CONFIG_HWSPINLOCK int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev, const struct hwspinlock_ops *ops, int base_id, int num_locks); int hwspin_lock_unregister(struct hwspinlock_device *bank); -struct hwspinlock *hwspin_lock_request(void); struct hwspinlock *hwspin_lock_request_specific(unsigned int id); int hwspin_lock_free(struct hwspinlock *hwlock); -int hwspin_lock_get_id(struct hwspinlock *hwlock); +int of_hwspin_lock_get_id(struct device_node *np, int index); int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int, unsigned long *); int __hwspin_trylock(struct hwspinlock *, int, unsigned long *); void __hwspin_unlock(struct hwspinlock *, int, unsigned long *); +int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name); +int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id); +int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock); +struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev, + unsigned int id); +int devm_hwspin_lock_unregister(struct device *dev, + struct hwspinlock_device *bank); +int devm_hwspin_lock_register(struct device *dev, + struct hwspinlock_device *bank, + const struct hwspinlock_ops *ops, + int base_id, int num_locks); #else /* !CONFIG_HWSPINLOCK */ @@ -87,11 +92,6 @@ void __hwspin_unlock(struct hwspinlock *, int, unsigned long *); * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking * users. Others, which care, can still check this with IS_ERR. */ -static inline struct hwspinlock *hwspin_lock_request(void) -{ - return ERR_PTR(-ENODEV); -} - static inline struct hwspinlock *hwspin_lock_request_specific(unsigned int id) { return ERR_PTR(-ENODEV); @@ -120,11 +120,35 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) { } -static inline int hwspin_lock_get_id(struct hwspinlock *hwlock) +static inline int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id) +{ + return 0; +} + +static inline int of_hwspin_lock_get_id(struct device_node *np, int index) { return 0; } +static inline +int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name) +{ + return 0; +} + +static inline +int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock) +{ + return 0; +} + +static inline +struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev, + unsigned int id) +{ + return ERR_PTR(-ENODEV); +} + #endif /* !CONFIG_HWSPINLOCK */ /** @@ -169,6 +193,42 @@ static inline int hwspin_trylock_irq(struct hwspinlock *hwlock) } /** + * hwspin_trylock_raw() - attempt to lock a specific hwspinlock + * @hwlock: an hwspinlock which we want to trylock + * + * This function attempts to lock an hwspinlock, and will immediately fail + * if the hwspinlock is already taken. + * + * Caution: User must protect the routine of getting hardware lock with mutex + * or spinlock to avoid dead-lock, that will let user can do some time-consuming + * or sleepable operations under the hardware lock. + * + * Returns 0 if we successfully locked the hwspinlock, -EBUSY if + * the hwspinlock was already taken, and -EINVAL if @hwlock is invalid. + */ +static inline int hwspin_trylock_raw(struct hwspinlock *hwlock) +{ + return __hwspin_trylock(hwlock, HWLOCK_RAW, NULL); +} + +/** + * hwspin_trylock_in_atomic() - attempt to lock a specific hwspinlock + * @hwlock: an hwspinlock which we want to trylock + * + * This function attempts to lock an hwspinlock, and will immediately fail + * if the hwspinlock is already taken. + * + * This function shall be called only from an atomic context. + * + * Returns 0 if we successfully locked the hwspinlock, -EBUSY if + * the hwspinlock was already taken, and -EINVAL if @hwlock is invalid. + */ +static inline int hwspin_trylock_in_atomic(struct hwspinlock *hwlock) +{ + return __hwspin_trylock(hwlock, HWLOCK_IN_ATOMIC, NULL); +} + +/** * hwspin_trylock() - attempt to lock a specific hwspinlock * @hwlock: an hwspinlock which we want to trylock * @@ -236,6 +296,51 @@ int hwspin_lock_timeout_irq(struct hwspinlock *hwlock, unsigned int to) } /** + * hwspin_lock_timeout_raw() - lock an hwspinlock with timeout limit + * @hwlock: the hwspinlock to be locked + * @to: timeout value in msecs + * + * This function locks the underlying @hwlock. If the @hwlock + * is already taken, the function will busy loop waiting for it to + * be released, but give up when @timeout msecs have elapsed. + * + * Caution: User must protect the routine of getting hardware lock with mutex + * or spinlock to avoid dead-lock, that will let user can do some time-consuming + * or sleepable operations under the hardware lock. + * + * Returns 0 when the @hwlock was successfully taken, and an appropriate + * error code otherwise (most notably an -ETIMEDOUT if the @hwlock is still + * busy after @timeout msecs). The function will never sleep. + */ +static inline +int hwspin_lock_timeout_raw(struct hwspinlock *hwlock, unsigned int to) +{ + return __hwspin_lock_timeout(hwlock, to, HWLOCK_RAW, NULL); +} + +/** + * hwspin_lock_timeout_in_atomic() - lock an hwspinlock with timeout limit + * @hwlock: the hwspinlock to be locked + * @to: timeout value in msecs + * + * This function locks the underlying @hwlock. If the @hwlock + * is already taken, the function will busy loop waiting for it to + * be released, but give up when @timeout msecs have elapsed. + * + * This function shall be called only from an atomic context and the timeout + * value shall not exceed a few msecs. + * + * Returns 0 when the @hwlock was successfully taken, and an appropriate + * error code otherwise (most notably an -ETIMEDOUT if the @hwlock is still + * busy after @timeout msecs). The function will never sleep. + */ +static inline +int hwspin_lock_timeout_in_atomic(struct hwspinlock *hwlock, unsigned int to) +{ + return __hwspin_lock_timeout(hwlock, to, HWLOCK_IN_ATOMIC, NULL); +} + +/** * hwspin_lock_timeout() - lock an hwspinlock with timeout limit * @hwlock: the hwspinlock to be locked * @to: timeout value in msecs @@ -295,6 +400,36 @@ static inline void hwspin_unlock_irq(struct hwspinlock *hwlock) } /** + * hwspin_unlock_raw() - unlock hwspinlock + * @hwlock: a previously-acquired hwspinlock which we want to unlock + * + * This function will unlock a specific hwspinlock. + * + * @hwlock must be already locked (e.g. by hwspin_trylock()) before calling + * this function: it is a bug to call unlock on a @hwlock that is already + * unlocked. + */ +static inline void hwspin_unlock_raw(struct hwspinlock *hwlock) +{ + __hwspin_unlock(hwlock, HWLOCK_RAW, NULL); +} + +/** + * hwspin_unlock_in_atomic() - unlock hwspinlock + * @hwlock: a previously-acquired hwspinlock which we want to unlock + * + * This function will unlock a specific hwspinlock. + * + * @hwlock must be already locked (e.g. by hwspin_trylock()) before calling + * this function: it is a bug to call unlock on a @hwlock that is already + * unlocked. + */ +static inline void hwspin_unlock_in_atomic(struct hwspinlock *hwlock) +{ + __hwspin_unlock(hwlock, HWLOCK_IN_ATOMIC, NULL); +} + +/** * hwspin_unlock() - unlock hwspinlock * @hwlock: a previously-acquired hwspinlock which we want to unlock * |