linux/drivers/hwspinlock/hwspinlock_internal.h

60 lines
1.9 KiB
C

/*
* Hardware spinlocks internal 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 __HWSPINLOCK_HWSPINLOCK_H
#define __HWSPINLOCK_HWSPINLOCK_H
#include <linux/spinlock.h>
#include <linux/device.h>
/**
* struct hwspinlock_ops - platform-specific hwspinlock handlers
*
* @trylock: make a single attempt to take the lock. returns 0 on
* failure and true on success. may _not_ sleep.
* @unlock: release the lock. always succeed. may _not_ sleep.
* @relax: optional, platform-specific relax handler, called by hwspinlock
* core while spinning on a lock, between two successive
* invocations of @trylock. may _not_ sleep.
*/
struct hwspinlock_ops {
int (*trylock)(struct hwspinlock *lock);
void (*unlock)(struct hwspinlock *lock);
void (*relax)(struct hwspinlock *lock);
};
/**
* struct hwspinlock - this struct represents a single hwspinlock instance
*
* @dev: underlying device, will be used to invoke runtime PM api
* @ops: platform-specific hwspinlock handlers
* @id: a global, unique, system-wide, index of the lock.
* @lock: initialized and used by hwspinlock core
*
* Note: currently simplicity was opted for, but later we can squeeze some
* memory bytes by grouping dev, ops in a single
* per-platform struct, and have all hwspinlocks point at it.
*/
struct hwspinlock {
struct device *dev;
const struct hwspinlock_ops *ops;
int id;
spinlock_t lock;
};
#endif /* __HWSPINLOCK_HWSPINLOCK_H */