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