1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef __LINUX_GPIO_SHARED_H
4#define __LINUX_GPIO_SHARED_H
5
6#include <linux/cleanup.h>
7#include <linux/lockdep.h>
8#include <linux/mutex.h>
9#include <linux/spinlock.h>
10
11struct gpio_device;
12struct gpio_desc;
13struct device;
14
15#if IS_ENABLED(CONFIG_GPIO_SHARED)
16
17int gpio_device_setup_shared(struct gpio_device *gdev);
18void gpio_device_teardown_shared(struct gpio_device *gdev);
19int gpio_shared_add_proxy_lookup(struct device *consumer, const char *con_id,
20 unsigned long lflags);
21
22#else
23
24static inline int gpio_device_setup_shared(struct gpio_device *gdev)
25{
26 return 0;
27}
28
29static inline void gpio_device_teardown_shared(struct gpio_device *gdev) { }
30
31static inline int gpio_shared_add_proxy_lookup(struct device *consumer,
32 const char *con_id,
33 unsigned long lflags)
34{
35 return 0;
36}
37
38#endif /* CONFIG_GPIO_SHARED */
39
40struct gpio_shared_desc {
41 struct gpio_desc *desc;
42 bool can_sleep;
43 unsigned long cfg;
44 unsigned int usecnt;
45 unsigned int highcnt;
46 union {
47 struct mutex mutex;
48 spinlock_t spinlock;
49 };
50};
51
52struct gpio_shared_desc *devm_gpiod_shared_get(struct device *dev);
53
54DEFINE_LOCK_GUARD_1(gpio_shared_desc_lock, struct gpio_shared_desc,
55 if (_T->lock->can_sleep)
56 mutex_lock(&_T->lock->mutex);
57 else
58 spin_lock_irqsave(&_T->lock->spinlock, _T->flags),
59 if (_T->lock->can_sleep)
60 mutex_unlock(&_T->lock->mutex);
61 else
62 spin_unlock_irqrestore(&_T->lock->spinlock, _T->flags),
63 unsigned long flags)
64
65static inline void gpio_shared_lockdep_assert(struct gpio_shared_desc *shared_desc)
66{
67 if (shared_desc->can_sleep)
68 lockdep_assert_held(&shared_desc->mutex);
69 else
70 lockdep_assert_held(&shared_desc->spinlock);
71}
72
73#endif /* __LINUX_GPIO_SHARED_H */
74

source code of linux/drivers/gpio/gpiolib-shared.h