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
11 struct gpio_device;
12 struct gpio_desc;
13 struct device;
14 struct fwnode_handle;
15
16 #if IS_ENABLED(CONFIG_GPIO_SHARED)
17
18 int gpiochip_setup_shared(struct gpio_chip *gc);
19 void gpio_device_teardown_shared(struct gpio_device *gdev);
20 int gpio_shared_add_proxy_lookup(struct device *consumer,
21 struct fwnode_handle *fwnode,
22 const char *con_id, unsigned long lflags);
23
24 #else
25
gpiochip_setup_shared(struct gpio_chip * gc)26 static inline int gpiochip_setup_shared(struct gpio_chip *gc)
27 {
28 return 0;
29 }
30
gpio_device_teardown_shared(struct gpio_device * gdev)31 static inline void gpio_device_teardown_shared(struct gpio_device *gdev) { }
32
gpio_shared_add_proxy_lookup(struct device * consumer,struct fwnode_handle * fwnode,const char * con_id,unsigned long lflags)33 static inline int gpio_shared_add_proxy_lookup(struct device *consumer,
34 struct fwnode_handle *fwnode,
35 const char *con_id,
36 unsigned long lflags)
37 {
38 return 0;
39 }
40
41 #endif /* CONFIG_GPIO_SHARED */
42
43 struct gpio_shared_desc {
44 struct gpio_desc *desc;
45 bool can_sleep;
46 unsigned long cfg;
47 unsigned int usecnt;
48 unsigned int highcnt;
49 union {
50 struct mutex mutex;
51 spinlock_t spinlock;
52 };
53 };
54
55 struct gpio_shared_desc *devm_gpiod_shared_get(struct device *dev);
56
57 DEFINE_LOCK_GUARD_1(gpio_shared_desc_lock, struct gpio_shared_desc,
58 if (_T->lock->can_sleep)
59 mutex_lock(&_T->lock->mutex);
60 else
61 spin_lock_irqsave(&_T->lock->spinlock, _T->flags),
62 if (_T->lock->can_sleep)
63 mutex_unlock(&_T->lock->mutex);
64 else
65 spin_unlock_irqrestore(&_T->lock->spinlock, _T->flags),
66 unsigned long flags)
67
gpio_shared_lockdep_assert(struct gpio_shared_desc * shared_desc)68 static inline void gpio_shared_lockdep_assert(struct gpio_shared_desc *shared_desc)
69 {
70 if (shared_desc->can_sleep)
71 lockdep_assert_held(&shared_desc->mutex);
72 else
73 lockdep_assert_held(&shared_desc->spinlock);
74 }
75
76 #endif /* __LINUX_GPIO_SHARED_H */
77