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-rw-r--r--drivers/staging/iio/trigger.h151
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diff --git a/drivers/staging/iio/trigger.h b/drivers/staging/iio/trigger.h
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+/* The industrial I/O core, trigger handling functions
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#ifndef _IIO_TRIGGER_H_
+#define _IIO_TRIGGER_H_
+#define IIO_TRIGGER_NAME_LENGTH 20
+#define IIO_TRIGGER_ID_PREFIX "iio:trigger"
+#define IIO_TRIGGER_ID_FORMAT IIO_TRIGGER_ID_PREFIX "%d"
+
+
+/**
+ * struct iio_trigger - industrial I/O trigger device
+ *
+ * @id: [INTERN] unique id number
+ * @name: [DRIVER] unique name
+ * @dev: [DRIVER] associated device (if relevant)
+ * @sysfs_dev: [INTERN] sysfs relevant device
+ * @private_data: [DRIVER] device specific data
+ * @list: [INTERN] used in maintenance of global trigger list
+ * @alloc_list: [DRIVER] used for driver specific trigger list
+ * @poll_func_list_lock:[INTERN] protection of the polling function list
+ * @pollfunc_list: [INTERN] list of functions to run on trigger.
+ * @control_attrs: [DRIVER] sysfs attributes relevant to trigger type
+ * @set_trigger_state: [DRIVER] switch on/off the trigger on demand
+ * @timestamp: [INTERN] timestamp usesd by some trigs (e.g. datardy)
+ * @owner: [DRIVER] used to monitor usage count of the trigger.
+ **/
+struct iio_trigger {
+ int id;
+ const char *name;
+ struct device dev;
+
+ void *private_data;
+ struct list_head list;
+ struct list_head alloc_list;
+ spinlock_t pollfunc_list_lock;
+ struct list_head pollfunc_list;
+ const struct attribute_group *control_attrs;
+ s64 timestamp;
+ struct module *owner;
+ int use_count;
+
+ int (*set_trigger_state)(struct iio_trigger *trig, bool state);
+ int (*try_reenable)(struct iio_trigger *trig);
+};
+
+static inline struct iio_trigger *to_iio_trigger(struct device *d)
+{
+ return container_of(d, struct iio_trigger, dev);
+};
+
+static inline void iio_put_trigger(struct iio_trigger *trig)
+{
+ put_device(&trig->dev);
+ module_put(trig->owner);
+};
+
+static inline void iio_get_trigger(struct iio_trigger *trig)
+{
+ __module_get(trig->owner);
+ get_device(&trig->dev);
+};
+
+/**
+ * iio_trigger_read_name() - sysfs access function to get the trigger name
+ **/
+ssize_t iio_trigger_read_name(struct device *dev,
+ struct device_attribute *attr,
+ char *buf);
+
+#define IIO_TRIGGER_NAME_ATTR DEVICE_ATTR(name, S_IRUGO, \
+ iio_trigger_read_name, \
+ NULL);
+
+/**
+ * iio_trigger_find_by_name() - search global trigger list
+ **/
+struct iio_trigger *iio_trigger_find_by_name(const char *name, size_t len);
+
+/**
+ * iio_trigger_register() - register a trigger with the IIO core
+ * @trig_info: trigger to be registered
+ **/
+int iio_trigger_register(struct iio_trigger *trig_info);
+
+/**
+ * iio_trigger_unregister() - unregister a trigger from the core
+ **/
+void iio_trigger_unregister(struct iio_trigger *trig_info);
+
+/**
+ * iio_trigger_attach_poll_func() - add a function pair to be run on trigger
+ * @trig: trigger to which the function pair are being added
+ * @pf: poll function pair
+ **/
+int iio_trigger_attach_poll_func(struct iio_trigger *trig,
+ struct iio_poll_func *pf);
+
+/**
+ * iio_trigger_dettach_poll_func() - remove function pair from those to be
+ * run on trigger.
+ * @trig: trigger from which the function is being removed.
+ * @pf: poll function pair
+ **/
+int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
+ struct iio_poll_func *pf);
+
+/**
+ * iio_trigger_poll() - called on a trigger occuring
+ * Typically called in relevant hardware interrupt handler.
+ **/
+void iio_trigger_poll(struct iio_trigger *);
+void iio_trigger_notify_done(struct iio_trigger *);
+
+/**
+ * struct iio_poll_func - poll function pair
+ *
+ * @list: associate this with a triggers pollfunc_list
+ * @private_data: data specific to device (passed into poll func)
+ * @poll_func_immediate: function in here is run first. They should be
+ * extremely lightweight. Typically used for latch
+ * control on sensor supporting it.
+ * @poll_func_main: function in here is run after all immediates.
+ * Reading from sensor etc typically involves
+ * scheduling
+ * from here.
+ *
+ * The two stage approach used here only important when multiple sensors are
+ * being triggered by a single trigger. This really comes into it's own with
+ * simultaneous sampling devices where a simple latch command can be used to
+ * make the device store the values on all inputs.
+ **/
+struct iio_poll_func {
+ struct list_head list;
+ void *private_data;
+ void (*poll_func_immediate)(struct iio_dev *indio_dev);
+ void (*poll_func_main)(struct iio_dev *private_data);
+
+};
+
+struct iio_trigger *iio_allocate_trigger(void);
+
+void iio_free_trigger(struct iio_trigger *trig);
+
+
+#endif /* _IIO_TRIGGER_H_ */