1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* The industrial I/O core, trigger handling functions
3 *
4 * Copyright (c) 2008 Jonathan Cameron
5 */
6 #include <linux/irq.h>
7 #include <linux/module.h>
8 #include <linux/atomic.h>
9
10 #ifndef _IIO_TRIGGER_H_
11 #define _IIO_TRIGGER_H_
12
13 #ifdef CONFIG_IIO_TRIGGER
14 struct iio_subirq {
15 bool enabled;
16 };
17
18 struct iio_dev;
19 struct iio_trigger;
20
21 /**
22 * struct iio_trigger_ops - operations structure for an iio_trigger.
23 * @set_trigger_state: switch on/off the trigger on demand
24 * @reenable: function to reenable the trigger when the
25 * use count is zero (may be NULL)
26 * @validate_device: function to validate the device when the
27 * current trigger gets changed.
28 *
29 * This is typically static const within a driver and shared by
30 * instances of a given device.
31 **/
32 struct iio_trigger_ops {
33 int (*set_trigger_state)(struct iio_trigger *trig, bool state);
34 void (*reenable)(struct iio_trigger *trig);
35 int (*validate_device)(struct iio_trigger *trig,
36 struct iio_dev *indio_dev);
37 };
38
39
40 /**
41 * struct iio_trigger - industrial I/O trigger device
42 * @ops: [DRIVER] operations structure
43 * @owner: [INTERN] owner of this driver module
44 * @id: [INTERN] unique id number
45 * @name: [DRIVER] unique name
46 * @dev: [DRIVER] associated device (if relevant)
47 * @list: [INTERN] used in maintenance of global trigger list
48 * @alloc_list: [DRIVER] used for driver specific trigger list
49 * @use_count: [INTERN] use count for the trigger.
50 * @subirq_chip: [INTERN] associate 'virtual' irq chip.
51 * @subirq_base: [INTERN] base number for irqs provided by trigger.
52 * @subirqs: [INTERN] information about the 'child' irqs.
53 * @pool: [INTERN] bitmap of irqs currently in use.
54 * @pool_lock: [INTERN] protection of the irq pool.
55 * @attached_own_device:[INTERN] if we are using our own device as trigger,
56 * i.e. if we registered a poll function to the same
57 * device as the one providing the trigger.
58 * @reenable_work: [INTERN] work item used to ensure reenable can sleep.
59 **/
60 struct iio_trigger {
61 const struct iio_trigger_ops *ops;
62 struct module *owner;
63 int id;
64 const char *name;
65 struct device dev;
66
67 struct list_head list;
68 struct list_head alloc_list;
69 atomic_t use_count;
70
71 struct irq_chip subirq_chip;
72 int subirq_base;
73
74 struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
75 unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
76 struct mutex pool_lock;
77 bool attached_own_device;
78 struct work_struct reenable_work;
79 };
80
81
to_iio_trigger(struct device * d)82 static inline struct iio_trigger *to_iio_trigger(struct device *d)
83 {
84 return container_of(d, struct iio_trigger, dev);
85 }
86
iio_trigger_put(struct iio_trigger * trig)87 static inline void iio_trigger_put(struct iio_trigger *trig)
88 {
89 module_put(trig->owner);
90 put_device(&trig->dev);
91 }
92
iio_trigger_get(struct iio_trigger * trig)93 static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
94 {
95 get_device(&trig->dev);
96
97 WARN_ONCE(list_empty(&trig->list),
98 "Getting non-registered iio trigger %s is prohibited\n",
99 trig->name);
100
101 __module_get(trig->owner);
102
103 return trig;
104 }
105
106 /**
107 * iio_trigger_set_drvdata() - Set trigger driver data
108 * @trig: IIO trigger structure
109 * @data: Driver specific data
110 *
111 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
112 * retrieved by iio_trigger_get_drvdata().
113 */
iio_trigger_set_drvdata(struct iio_trigger * trig,void * data)114 static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
115 {
116 dev_set_drvdata(&trig->dev, data);
117 }
118
119 /**
120 * iio_trigger_get_drvdata() - Get trigger driver data
121 * @trig: IIO trigger structure
122 *
123 * Returns the data previously set with iio_trigger_set_drvdata()
124 */
iio_trigger_get_drvdata(struct iio_trigger * trig)125 static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
126 {
127 return dev_get_drvdata(&trig->dev);
128 }
129
130 /**
131 * iio_trigger_register() - register a trigger with the IIO core
132 * @trig_info: trigger to be registered
133 **/
134 int iio_trigger_register(struct iio_trigger *trig_info);
135
136 int devm_iio_trigger_register(struct device *dev,
137 struct iio_trigger *trig_info);
138
139 /**
140 * iio_trigger_unregister() - unregister a trigger from the core
141 * @trig_info: trigger to be unregistered
142 **/
143 void iio_trigger_unregister(struct iio_trigger *trig_info);
144
145 /**
146 * iio_trigger_set_immutable() - set an immutable trigger on destination
147 *
148 * @indio_dev: IIO device structure containing the device
149 * @trig: trigger to assign to device
150 *
151 **/
152 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
153
154 /**
155 * iio_trigger_poll() - called on a trigger occurring
156 * @trig: trigger which occurred
157 *
158 * Typically called in relevant hardware interrupt handler.
159 **/
160 void iio_trigger_poll(struct iio_trigger *trig);
161 void iio_trigger_poll_chained(struct iio_trigger *trig);
162
163 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
164
165 #define iio_trigger_alloc(parent, fmt, ...) \
166 __iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)
167
168 __printf(3, 4)
169 struct iio_trigger *__iio_trigger_alloc(struct device *parent,
170 struct module *this_mod,
171 const char *fmt, ...);
172 void iio_trigger_free(struct iio_trigger *trig);
173
174 /**
175 * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
176 * @indio_dev: device to check
177 */
178 bool iio_trigger_using_own(struct iio_dev *indio_dev);
179
180 int iio_trigger_validate_own_device(struct iio_trigger *trig,
181 struct iio_dev *indio_dev);
182
183 #else
184 struct iio_trigger;
185 struct iio_trigger_ops;
186 #endif
187 #endif /* _IIO_TRIGGER_H_ */
188