drivers/hwspinlock/hwspinlock_internal.h

   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 */