OpenCloudOS-Kernel/include/linux/iio/trigger.h

179 lines
5.0 KiB
C
Raw Normal View History

/* 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.
*/
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/atomic.h>
#ifndef _IIO_TRIGGER_H_
#define _IIO_TRIGGER_H_
#ifdef CONFIG_IIO_TRIGGER
struct iio_subirq {
bool enabled;
};
struct iio_dev;
struct iio_trigger;
/**
* struct iio_trigger_ops - operations structure for an iio_trigger.
* @owner: used to monitor usage count of the trigger.
* @set_trigger_state: switch on/off the trigger on demand
* @try_reenable: function to reenable the trigger when the
* use count is zero (may be NULL)
* @validate_device: function to validate the device when the
* current trigger gets changed.
*
* This is typically static const within a driver and shared by
* instances of a given device.
**/
struct iio_trigger_ops {
struct module *owner;
int (*set_trigger_state)(struct iio_trigger *trig, bool state);
int (*try_reenable)(struct iio_trigger *trig);
int (*validate_device)(struct iio_trigger *trig,
struct iio_dev *indio_dev);
};
/**
* struct iio_trigger - industrial I/O trigger device
* @ops: [DRIVER] operations structure
* @id: [INTERN] unique id number
* @name: [DRIVER] unique name
* @dev: [DRIVER] associated device (if relevant)
* @list: [INTERN] used in maintenance of global trigger list
* @alloc_list: [DRIVER] used for driver specific trigger list
* @use_count: use count for the trigger
* @subirq_chip: [INTERN] associate 'virtual' irq chip.
* @subirq_base: [INTERN] base number for irqs provided by trigger.
* @subirqs: [INTERN] information about the 'child' irqs.
* @pool: [INTERN] bitmap of irqs currently in use.
* @pool_lock: [INTERN] protection of the irq pool.
iio: trigger: helpers to determine own trigger This adds a helper function to the IIO trigger framework: iio_trigger_using_own(): for an IIO device, this tells whether the device is using itself as a trigger. This is true if the indio device: (A) supplies a trigger and (B) has assigned its own buffer poll function to use this trigger. This helper function is good when constructing triggered, buffered drivers that can either use its own hardware *OR* an external trigger such as a HRTimer or even the trigger from a totally different sensor. Under such circumstances it is important to know for example if the timestamp from the same trigger hardware should be used when populating the buffer: if iio_trigger_using_own() is true, we can use this timestamp, else we need to pick a unique timestamp directly in the trigger handler. For this to work of course IIO devices registering hardware triggers must follow the convention to set the parent device properly, as as well as setting the parent of the IIO device itself. When a new poll function is attached, we check if the parent device of the IIO of the poll function is the same as the parent device of the trigger and in that case we conclude that the hardware is using itself as trigger. Cc: Giuseppe Barba <giuseppe.barba@st.com> Cc: Denis Ciocca <denis.ciocca@st.com> Cc: Crestez Dan Leonard <leonard.crestez@intel.com> Cc: Gregor Boirie <gregor.boirie@parrot.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-01 16:27:17 +08:00
* @attached_own_device:[INTERN] if we are using our own device as trigger,
* i.e. if we registered a poll function to the same
* device as the one providing the trigger.
**/
struct iio_trigger {
const struct iio_trigger_ops *ops;
int id;
const char *name;
struct device dev;
struct list_head list;
struct list_head alloc_list;
atomic_t use_count;
struct irq_chip subirq_chip;
int subirq_base;
struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
struct mutex pool_lock;
iio: trigger: helpers to determine own trigger This adds a helper function to the IIO trigger framework: iio_trigger_using_own(): for an IIO device, this tells whether the device is using itself as a trigger. This is true if the indio device: (A) supplies a trigger and (B) has assigned its own buffer poll function to use this trigger. This helper function is good when constructing triggered, buffered drivers that can either use its own hardware *OR* an external trigger such as a HRTimer or even the trigger from a totally different sensor. Under such circumstances it is important to know for example if the timestamp from the same trigger hardware should be used when populating the buffer: if iio_trigger_using_own() is true, we can use this timestamp, else we need to pick a unique timestamp directly in the trigger handler. For this to work of course IIO devices registering hardware triggers must follow the convention to set the parent device properly, as as well as setting the parent of the IIO device itself. When a new poll function is attached, we check if the parent device of the IIO of the poll function is the same as the parent device of the trigger and in that case we conclude that the hardware is using itself as trigger. Cc: Giuseppe Barba <giuseppe.barba@st.com> Cc: Denis Ciocca <denis.ciocca@st.com> Cc: Crestez Dan Leonard <leonard.crestez@intel.com> Cc: Gregor Boirie <gregor.boirie@parrot.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-01 16:27:17 +08:00
bool attached_own_device;
};
static inline struct iio_trigger *to_iio_trigger(struct device *d)
{
return container_of(d, struct iio_trigger, dev);
}
static inline void iio_trigger_put(struct iio_trigger *trig)
{
module_put(trig->ops->owner);
put_device(&trig->dev);
}
static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
{
get_device(&trig->dev);
__module_get(trig->ops->owner);
return trig;
}
/**
* iio_device_set_drvdata() - Set trigger driver data
* @trig: IIO trigger structure
* @data: Driver specific data
*
* Allows to attach an arbitrary pointer to an IIO trigger, which can later be
* retrieved by iio_trigger_get_drvdata().
*/
static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
{
dev_set_drvdata(&trig->dev, data);
}
/**
* iio_trigger_get_drvdata() - Get trigger driver data
* @trig: IIO trigger structure
*
* Returns the data previously set with iio_trigger_set_drvdata()
*/
static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
{
return dev_get_drvdata(&trig->dev);
}
/**
* 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);
int devm_iio_trigger_register(struct device *dev,
struct iio_trigger *trig_info);
/**
* iio_trigger_unregister() - unregister a trigger from the core
* @trig_info: trigger to be unregistered
**/
void iio_trigger_unregister(struct iio_trigger *trig_info);
void devm_iio_trigger_unregister(struct device *dev,
struct iio_trigger *trig_info);
/**
* iio_trigger_set_immutable() - set an immutable trigger on destination
*
* @indio_dev - IIO device structure containing the device
* @trig - trigger to assign to device
*
**/
int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
/**
* iio_trigger_poll() - called on a trigger occurring
* @trig: trigger which occurred
*
* Typically called in relevant hardware interrupt handler.
**/
void iio_trigger_poll(struct iio_trigger *trig);
void iio_trigger_poll_chained(struct iio_trigger *trig);
irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
__printf(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
void iio_trigger_free(struct iio_trigger *trig);
iio: trigger: helpers to determine own trigger This adds a helper function to the IIO trigger framework: iio_trigger_using_own(): for an IIO device, this tells whether the device is using itself as a trigger. This is true if the indio device: (A) supplies a trigger and (B) has assigned its own buffer poll function to use this trigger. This helper function is good when constructing triggered, buffered drivers that can either use its own hardware *OR* an external trigger such as a HRTimer or even the trigger from a totally different sensor. Under such circumstances it is important to know for example if the timestamp from the same trigger hardware should be used when populating the buffer: if iio_trigger_using_own() is true, we can use this timestamp, else we need to pick a unique timestamp directly in the trigger handler. For this to work of course IIO devices registering hardware triggers must follow the convention to set the parent device properly, as as well as setting the parent of the IIO device itself. When a new poll function is attached, we check if the parent device of the IIO of the poll function is the same as the parent device of the trigger and in that case we conclude that the hardware is using itself as trigger. Cc: Giuseppe Barba <giuseppe.barba@st.com> Cc: Denis Ciocca <denis.ciocca@st.com> Cc: Crestez Dan Leonard <leonard.crestez@intel.com> Cc: Gregor Boirie <gregor.boirie@parrot.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-01 16:27:17 +08:00
/**
* iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
* @indio_dev: device to check
*/
bool iio_trigger_using_own(struct iio_dev *indio_dev);
#else
struct iio_trigger;
struct iio_trigger_ops;
#endif
#endif /* _IIO_TRIGGER_H_ */