drivers/hwspinlock/hwspinlock_internal.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * Hardware spinlocks internal header
0004  *
0005  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
0006  *
0007  * Contact: Ohad Ben-Cohen <ohad@wizery.com>
0008  */
0009
0010 #ifndef __HWSPINLOCK_HWSPINLOCK_H
0011 #define __HWSPINLOCK_HWSPINLOCK_H
0012
0013 #include <linux/spinlock.h>
0014 #include <linux/device.h>
0015
0016 struct hwspinlock_device;
0017
0018 /**
0019  * struct hwspinlock_ops - platform-specific hwspinlock handlers
0020  *
0021  * @trylock: make a single attempt to take the lock. returns 0 on
0022  *       failure and true on success. may _not_ sleep.
0023  * @unlock:  release the lock. always succeed. may _not_ sleep.
0024  * @relax:   optional, platform-specific relax handler, called by hwspinlock
0025  *       core while spinning on a lock, between two successive
0026  *       invocations of @trylock. may _not_ sleep.
0027  */
0028 struct hwspinlock_ops {
0029     int (*trylock)(struct hwspinlock *lock);
0030     void (*unlock)(struct hwspinlock *lock);
0031     void (*relax)(struct hwspinlock *lock);
0032 };
0033
0034 /**
0035  * struct hwspinlock - this struct represents a single hwspinlock instance
0036  * @bank: the hwspinlock_device structure which owns this lock
0037  * @lock: initialized and used by hwspinlock core
0038  * @priv: private data, owned by the underlying platform-specific hwspinlock drv
0039  */
0040 struct hwspinlock {
0041     struct hwspinlock_device *bank;
0042     spinlock_t lock;
0043     void *priv;
0044 };
0045
0046 /**
0047  * struct hwspinlock_device - a device which usually spans numerous hwspinlocks
0048  * @dev: underlying device, will be used to invoke runtime PM api
0049  * @ops: platform-specific hwspinlock handlers
0050  * @base_id: id index of the first lock in this device
0051  * @num_locks: number of locks in this device
0052  * @lock: dynamically allocated array of 'struct hwspinlock'
0053  */
0054 struct hwspinlock_device {
0055     struct device *dev;
0056     const struct hwspinlock_ops *ops;
0057     int base_id;
0058     int num_locks;
0059     struct hwspinlock lock[];
0060 };
0061
0062 static inline int hwlock_to_id(struct hwspinlock *hwlock)
0063 {
0064     int local_id = hwlock - &hwlock->bank->lock[0];
0065
0066     return hwlock->bank->base_id + local_id;
0067 }
0068
0069 #endif /* __HWSPINLOCK_HWSPINLOCK_H */