include/linux/hwspinlock.h

Source file repositories/reference/linux-study-clean/include/linux/hwspinlock.h

File Facts

System
Linux kernel
Corpus path
include/linux/hwspinlock.h
Extension
.h
Size
14660 bytes
Lines
421
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __LINUX_HWSPINLOCK_H
#define __LINUX_HWSPINLOCK_H

#include <linux/err.h>
#include <linux/sched.h>

/* 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
#define HWLOCK_IN_ATOMIC	0x04 /* Called while in atomic context */

struct device;
struct device_node;
struct hwspinlock;
struct hwspinlock_device;
struct hwspinlock_ops;

#ifdef CONFIG_HWSPINLOCK

int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
		const struct hwspinlock_ops *ops, int base_id, int num_locks);
int hwspin_lock_unregister(struct hwspinlock_device *bank);
struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
int hwspin_lock_free(struct hwspinlock *hwlock);
int of_hwspin_lock_get_id(struct device_node *np, int index);
int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int,
							unsigned long *);
int __hwspin_trylock(struct hwspinlock *, int, unsigned long *);
void __hwspin_unlock(struct hwspinlock *, int, unsigned long *);
int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name);
int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id);
int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock);
struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev,
						     unsigned int id);
int devm_hwspin_lock_unregister(struct device *dev,
				struct hwspinlock_device *bank);
int devm_hwspin_lock_register(struct device *dev,
			      struct hwspinlock_device *bank,
			      const struct hwspinlock_ops *ops,
			      int base_id, int num_locks);

#else /* !CONFIG_HWSPINLOCK */

/*
 * We don't want these functions to fail if CONFIG_HWSPINLOCK is not
 * enabled. We prefer to silently succeed in this case, and let the
 * code path get compiled away. This way, if CONFIG_HWSPINLOCK is not
 * required on a given setup, users will still work.
 *
 * The only exception is hwspin_lock_register/hwspin_lock_unregister, with which
 * we _do_ want users to fail (no point in registering hwspinlock instances if
 * the framework is not available).
 *
 * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking
 * users. Others, which care, can still check this with IS_ERR.
 */
static inline struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
{
	return ERR_PTR(-ENODEV);
}

static inline int hwspin_lock_free(struct hwspinlock *hwlock)
{
	return 0;
}

static inline
int __hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int to,
					int mode, unsigned long *flags)
{
	return 0;
}

static inline
int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
{
	return 0;
}

static inline
void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
{
}

static inline int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id)
{
	return 0;
}

Annotation

Implementation Notes