1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Hardware spinlocks internal header
4  *
5  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
6  *
7  * Contact: Ohad Ben-Cohen <ohad@wizery.com>
8  */
9 
10 #ifndef __HWSPINLOCK_HWSPINLOCK_H
11 #define __HWSPINLOCK_HWSPINLOCK_H
12 
13 #include <linux/spinlock.h>
14 #include <linux/device.h>
15 
16 struct hwspinlock_device;
17 
18 /**
19  * struct hwspinlock_ops - platform-specific hwspinlock handlers
20  *
21  * @trylock: make a single attempt to take the lock. returns 0 on
22  *	     failure and true on success. may _not_ sleep.
23  * @unlock:  release the lock. always succeed. may _not_ sleep.
24  * @bust:    optional, platform-specific bust handler, called by hwspinlock
25  *	     core to bust a specific lock.
26  * @relax:   optional, platform-specific relax handler, called by hwspinlock
27  *	     core while spinning on a lock, between two successive
28  *	     invocations of @trylock. may _not_ sleep.
29  */
30 struct hwspinlock_ops {
31 	int (*trylock)(struct hwspinlock *lock);
32 	void (*unlock)(struct hwspinlock *lock);
33 	int (*bust)(struct hwspinlock *lock, unsigned int id);
34 	void (*relax)(struct hwspinlock *lock);
35 };
36 
37 /**
38  * struct hwspinlock - this struct represents a single hwspinlock instance
39  * @bank: the hwspinlock_device structure which owns this lock
40  * @lock: initialized and used by hwspinlock core
41  * @priv: private data, owned by the underlying platform-specific hwspinlock drv
42  */
43 struct hwspinlock {
44 	struct hwspinlock_device *bank;
45 	spinlock_t lock;
46 	void *priv;
47 };
48 
49 /**
50  * struct hwspinlock_device - a device which usually spans numerous hwspinlocks
51  * @dev: underlying device, will be used to invoke runtime PM api
52  * @ops: platform-specific hwspinlock handlers
53  * @base_id: id index of the first lock in this device
54  * @num_locks: number of locks in this device
55  * @lock: dynamically allocated array of 'struct hwspinlock'
56  */
57 struct hwspinlock_device {
58 	struct device *dev;
59 	const struct hwspinlock_ops *ops;
60 	int base_id;
61 	int num_locks;
62 	struct hwspinlock lock[];
63 };
64 
65 static inline int hwlock_to_id(struct hwspinlock *hwlock)
66 {
67 	int local_id = hwlock - &hwlock->bank->lock[0];
68 
69 	return hwlock->bank->base_id + local_id;
70 }
71 
72 #endif /* __HWSPINLOCK_HWSPINLOCK_H */
73