Commit 1637db44 authored by Jonathan Cameron's avatar Jonathan Cameron Committed by Greg Kroah-Hartman

Staging: IIO: Trigger support added to core.

Add general registration support for IIO triggers.  These
are currently only used to initialize a 'poll' of a given
device.  Examples include the lis3l02dq's data ready signal
being used to initialize a read and gpio triggers being
used to allow externally synchronized sensor reading.

Each trigger can cause any number of 'consumer' devices
to be polled with each storing data into a related ring
buffer.

Two stage triggering is supported with 'fast' and 'slow'
paths.  The first is used for things like pulling a data
hold line high and the second for actual read which
may take far longer.

Changes since V2:
* As with IIO triggers now use a registration approach
  much closer to that of input leading to cleaner code.
Signed-off-by: default avatarJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 574fb258
...@@ -17,6 +17,14 @@ config IIO_RING_BUFFER ...@@ -17,6 +17,14 @@ config IIO_RING_BUFFER
Provide core support for various ring buffer based data Provide core support for various ring buffer based data
acquisition methods. acquisition methods.
config IIO_TRIGGER
boolean "Enable triggered sampling support"
help
Provides IIO core support for triggers. Currently these
are used to initialize capture of samples to push into
ring buffers. The triggers are effectively a 'capture
data now' interrupt.
source "drivers/staging/iio/accel/Kconfig" source "drivers/staging/iio/accel/Kconfig"
source "drivers/staging/iio/adc/Kconfig" source "drivers/staging/iio/adc/Kconfig"
source "drivers/staging/iio/light/Kconfig" source "drivers/staging/iio/light/Kconfig"
......
...@@ -5,6 +5,7 @@ ...@@ -5,6 +5,7 @@
obj-$(CONFIG_IIO) += industrialio.o obj-$(CONFIG_IIO) += industrialio.o
industrialio-y := industrialio-core.o industrialio-y := industrialio-core.o
industrialio-$(CONFIG_IIO_RING_BUFFER) += industrialio-ring.o industrialio-$(CONFIG_IIO_RING_BUFFER) += industrialio-ring.o
industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
obj-y += accel/ obj-y += accel/
obj-y += adc/ obj-y += adc/
......
This diff is collapsed.
/* 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_ */
...@@ -8,6 +8,20 @@ ...@@ -8,6 +8,20 @@
* the Free Software Foundation. * the Free Software Foundation.
*/ */
#ifdef CONFIG_IIO_TRIGGER
/**
* iio_device_register_trigger_consumer() - set up an iio_dev to use triggers.
* @dev_info: iio_dev associated with the device that will consume the trigger
**/
int iio_device_register_trigger_consumer(struct iio_dev *dev_info);
/**
* iio_device_unregister_trigger_consumer() - reverse the registration process.
* @dev_info: iio_dev associated with the device that consumed the trigger
**/
int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info);
#else
/** /**
* iio_device_register_trigger_consumer() - set up an iio_dev to use triggers. * iio_device_register_trigger_consumer() - set up an iio_dev to use triggers.
* @dev_info: iio_dev associated with the device that will consume the trigger * @dev_info: iio_dev associated with the device that will consume the trigger
...@@ -18,9 +32,14 @@ int iio_device_register_trigger_consumer(struct iio_dev *dev_info) ...@@ -18,9 +32,14 @@ int iio_device_register_trigger_consumer(struct iio_dev *dev_info)
}; };
/** /**
* iio_device_unregister_trigger_consumer() - reverse the registration process * iio_device_unregister_trigger_consumer() - reverse the registration process
. * @dev_info: iio_dev associated with the device that consumed the trigger * @dev_info: iio_dev associated with the device that consumed the trigger
**/ **/
int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info) int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info)
{ {
return 0; return 0;
}; };
#endif /* CONFIG_TRIGGER_CONSUMER */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment