diff options
Diffstat (limited to 'include/linux/hwspinlock.h')
| -rw-r--r-- | include/linux/hwspinlock.h | 68 |
1 files changed, 59 insertions, 9 deletions
diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index 859d673..57537e6 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 @@ -24,6 +16,7 @@ /* hwspinlock mode argument */ #define HWLOCK_IRQSTATE 0x01 /* Disable interrupts, save state */ #define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */ +#define HWLOCK_RAW 0x03 struct device; struct device_node; @@ -176,6 +169,25 @@ 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() - attempt to lock a specific hwspinlock * @hwlock: an hwspinlock which we want to trylock * @@ -243,6 +255,29 @@ 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() - lock an hwspinlock with timeout limit * @hwlock: the hwspinlock to be locked * @to: timeout value in msecs @@ -302,6 +337,21 @@ 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() - unlock hwspinlock * @hwlock: a previously-acquired hwspinlock which we want to unlock * |
