Re: [PATCH 28/70] staging:iio: Add infrastructure for irq_chip based triggers

[Jonathan Cameron <jic23@cam.ac.uk>]

On 04/21/11 17:51, Jonathan Cameron wrote:
> Change of plan here.
> 
> It's perfectly possible, (but somewhat under utilized) to call irq_alloc_descs
> to give us a dynamically allocated range of irq's. It may be dependant on sparse irq
> though so will need to look into that or provide alternative method such
> as this one.

New implementation using that approach is now available in the iio-onwards tree.
Please take a look.  I'd like to start pushing some of this tree
out to Greg asap as it would be good to have it place for a while pre
merge window opening.  I'll be posting a new revision of the whole set
sometime in the next few days.  Before then I'm trying to squash the remaining
build issues with a few drivers.

Jonathan
>> fix to merge back for the incorrect multiple trigger handling
>>
>> V2: Stop silly name duplication.
>>     Move pool handling to industrialio-trigger as that is the only user.
>>     Changed over to using irq_modify_status rather than the arm
>>     specific set_irq_flags as per Thomas Gleixner's suggestion.
>>
>> Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
>> ---
>>  drivers/staging/Makefile                      |    2 +-
>>  drivers/staging/iio/Kconfig                   |   12 ++
>>  drivers/staging/iio/Makefile                  |    2 +
>>  drivers/staging/iio/iio-board-info.h          |   24 +++
>>  drivers/staging/iio/iio-core.h                |   13 ++
>>  drivers/staging/iio/industrialio-board-info.c |   25 +++
>>  drivers/staging/iio/industrialio-trigger.c    |  200 +++++++++++++++++++++----
>>  drivers/staging/iio/trigger.h                 |   57 +++++++-
>>  8 files changed, 298 insertions(+), 37 deletions(-)
>>
>> diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
>> index eb93012..0955c7c 100644
>> --- a/drivers/staging/Makefile
>> +++ b/drivers/staging/Makefile
>> @@ -41,7 +41,7 @@ obj-$(CONFIG_VT6656)		+= vt6656/
>>  obj-$(CONFIG_HYPERV)		+= hv/
>>  obj-$(CONFIG_VME_BUS)		+= vme/
>>  obj-$(CONFIG_DX_SEP)            += sep/
>> -obj-$(CONFIG_IIO)		+= iio/
>> +obj-y				+= iio/
>>  obj-$(CONFIG_CS5535_GPIO)	+= cs5535_gpio/
>>  obj-$(CONFIG_ZRAM)		+= zram/
>>  obj-$(CONFIG_XVMALLOC)		+= zram/
>> diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig
>> index 6775bf9..df9aa08 100644
>> --- a/drivers/staging/iio/Kconfig
>> +++ b/drivers/staging/iio/Kconfig
>> @@ -12,6 +12,10 @@ menuconfig IIO
>>  	  Documentation/industrialio for more information.
>>  if IIO
>>  
>> +config IIO_BOARDINFO
>> +       boolean
>> +       default y
>> +
>>  config IIO_RING_BUFFER
>>  	bool "Enable ring buffer support within IIO"
>>  	help
>> @@ -42,12 +46,20 @@ endif # IIO_RINGBUFFER
>>  
>>  config IIO_TRIGGER
>>  	boolean "Enable triggered sampling support"
>> +	depends on IIO_BOARDINFO
>>  	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.
>>  
>> +config IIO_CONSUMERS_PER_TRIGGER
>> +       int "Maximum number of consumers per trigger"
>> +       depends on IIO_TRIGGER
>> +       default "2"
>> +       help
>> +	This value controls the maximum number of consumers that a
>> +	given trigger may handle. Default is 2.
>>  
>>  source "drivers/staging/iio/accel/Kconfig"
>>  source "drivers/staging/iio/adc/Kconfig"
>> diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile
>> index bb5c95c..37b4d12 100644
>> --- a/drivers/staging/iio/Makefile
>> +++ b/drivers/staging/iio/Makefile
>> @@ -2,6 +2,8 @@
>>  # Makefile for the industrial I/O core.
>>  #
>>  
>> +obj-$(CONFIG_IIO_BOARDINFO) += industrialio-board-info.o
>> +
>>  obj-$(CONFIG_IIO) += industrialio.o
>>  industrialio-y := industrialio-core.o
>>  industrialio-$(CONFIG_IIO_RING_BUFFER) += industrialio-ring.o
>> diff --git a/drivers/staging/iio/iio-board-info.h b/drivers/staging/iio/iio-board-info.h
>> new file mode 100644
>> index 0000000..c608a4d
>> --- /dev/null
>> +++ b/drivers/staging/iio/iio-board-info.h
>> @@ -0,0 +1,24 @@
>> +/*
>> + * Board information for IIO.
>> + *
>> + * Copyright (c) 2011 Jonathan Cameron <jic23@cam.ac.uk>
>> + *
>> + * 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.
>> + */
>> +
>> +#ifdef CONFIG_IIO_BOARDINFO
>> +
>> +/**
>> + * iio_set_irq_pool() - provid iio with a pool of virtaul interrupts to use
>> + * @start: start of the pool
>> + * @num: number of interupts in the pool
>> + **/
>> +void iio_set_irq_pool(int start, int num);
>> +
>> +#else
>> +
>> +static inline void iio_set_irq_pool(int start, int num) {};
>> +
>> +#endif
>> diff --git a/drivers/staging/iio/iio-core.h b/drivers/staging/iio/iio-core.h
>> new file mode 100644
>> index 0000000..2c4f433
>> --- /dev/null
>> +++ b/drivers/staging/iio/iio-core.h
>> @@ -0,0 +1,13 @@
>> +/*
>> + * IIO core header. Should never be included by drivers.
>> + *
>> + * Copyright (c) 2011 Jonathan Cameron <jic23@cam.ac.uk>
>> + *
>> + * 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.
>> + */
>> +
>> +#define IIO_MAX_POOL 128
>> +extern int __iio_irqstart;
>> +extern int __iio_irqnum;
>> diff --git a/drivers/staging/iio/industrialio-board-info.c b/drivers/staging/iio/industrialio-board-info.c
>> new file mode 100644
>> index 0000000..28f9156
>> --- /dev/null
>> +++ b/drivers/staging/iio/industrialio-board-info.c
>> @@ -0,0 +1,25 @@
>> +/* IIO Board info
>> + *
>> + * Copyright (c) 2011 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/module.h>
>> +#include <linux/kernel.h>
>> +#include "iio-core.h"
>> +
>> +int __iio_irqstart;
>> +EXPORT_SYMBOL(__iio_irqstart);
>> +int __iio_irqnum;
>> +EXPORT_SYMBOL(__iio_irqnum);
>> +
>> +void __init iio_set_irq_pool(int start, int num)
>> +{
>> +	__iio_irqstart = start;
>> +	__iio_irqnum = num;
>> +	if (num > IIO_MAX_POOL)
>> +		__iio_irqnum = IIO_MAX_POOL;
>> +}
>> diff --git a/drivers/staging/iio/industrialio-trigger.c b/drivers/staging/iio/industrialio-trigger.c
>> index 083847c..9ccc789 100644
>> --- a/drivers/staging/iio/industrialio-trigger.c
>> +++ b/drivers/staging/iio/industrialio-trigger.c
>> @@ -19,6 +19,7 @@
>>  #include "iio.h"
>>  #include "trigger.h"
>>  #include "trigger_consumer.h"
>> +#include "iio-core.h"
>>  
>>  /* RFC - Question of approach
>>   * Make the common case (single sensor single trigger)
>> @@ -38,6 +39,31 @@ static DEFINE_SPINLOCK(iio_trigger_idr_lock);
>>  static LIST_HEAD(iio_trigger_list);
>>  static DEFINE_MUTEX(iio_trigger_list_lock);
>>  
>> +static DEFINE_MUTEX(iio_irq_pool_lock);
>> +static unsigned long iio_irq_pool_mask[BITS_TO_LONGS(IIO_MAX_POOL)] = {};
>> +
>> +static int iio_irq_pool_get_range(int num)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&iio_irq_pool_lock);
>> +	ret = bitmap_find_free_region(iio_irq_pool_mask,
>> +				      __iio_irqnum, ilog2(num));
>> +	if (ret >= 0)
>> +		ret += __iio_irqstart;
>> +	mutex_unlock(&iio_irq_pool_lock);
>> +
>> +	return ret;
>> +}
>> +
>> +static void iio_irq_pool_put_range(int start, int num)
>> +{
>> +	mutex_lock(&iio_irq_pool_lock);
>> +	bitmap_release_region(iio_irq_pool_mask,
>> +			      start - __iio_irqstart, ilog2(num));
>> +	mutex_unlock(&iio_irq_pool_lock);
>> +}
>> +
>>  /**
>>   * iio_trigger_register_sysfs() - create a device for this trigger
>>   * @trig_info:	the trigger
>> @@ -163,6 +189,7 @@ static struct iio_trigger *iio_trigger_find_by_name(const char *name,
>>  
>>  void iio_trigger_poll(struct iio_trigger *trig, s64 time)
>>  {
>> +	int i;
>>  	struct iio_poll_func *pf_cursor;
>>  
>>  	list_for_each_entry(pf_cursor, &trig->pollfunc_list, list) {
>> @@ -178,6 +205,13 @@ void iio_trigger_poll(struct iio_trigger *trig, s64 time)
>>  			trig->use_count++;
>>  		}
>>  	}
>> +	if (!trig->use_count) {
>> +		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
>> +			if (trig->subirqs[i].enabled) {
>> +				trig->use_count++;
>> +				generic_handle_irq(trig->subirq_base + i);
>> +			}
>> +	}
>>  }
>>  EXPORT_SYMBOL(iio_trigger_poll);
>>  
>> @@ -219,16 +253,31 @@ int iio_trigger_attach_poll_func(struct iio_trigger *trig,
>>  	int ret = 0;
>>  	unsigned long flags;
>>  
>> -	spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> -	list_add_tail(&pf->list, &trig->pollfunc_list);
>> -	spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>> -
>> -	if (trig->set_trigger_state)
>> -		ret = trig->set_trigger_state(trig, true);
>> -	if (ret) {
>> -		printk(KERN_ERR "set trigger state failed\n");
>> -		list_del(&pf->list);
>> +	if (pf->thread) {
>> +		bool notinuse
>> +			= bitmap_empty(trig->pool,
>> +				       CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> +
>> +		pf->irq = iio_trigger_get_irq(trig);
>> +		ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
>> +					   pf->type, pf->name,
>> +					   pf);
>> +		if (trig->set_trigger_state && notinuse) {
>> +			ret = trig->set_trigger_state(trig, true);
>> +	} else {
>> +		spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> +		list_add_tail(&pf->list, &trig->pollfunc_list);
>> +		spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>> +
>> +		if (trig->set_trigger_state)
>> +			ret = trig->set_trigger_state(trig, true);
>> +		}
>> +		if (ret) {
>> +			printk(KERN_ERR "set trigger state failed\n");
>> +			list_del(&pf->list);
>> +		}
>>  	}
>> +
>>  	return ret;
>>  }
>>  EXPORT_SYMBOL(iio_trigger_attach_poll_func);
>> @@ -240,37 +289,63 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
>>  	unsigned long flags;
>>  	int ret = -EINVAL;
>>  
>> -	spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> -	list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
>> -		if (pf_cursor == pf) {
>> -			ret = 0;
>> -			break;
>> -		}
>> -	if (!ret) {
>> -		if (list_is_singular(&trig->pollfunc_list)
>> -		    && trig->set_trigger_state) {
>> -			spin_unlock_irqrestore(&trig->pollfunc_list_lock,
>> -					       flags);
>> -			/* May sleep hence cannot hold the spin lock */
>> +	if (pf->thread) {
>> +		bool no_other_users
>> +			= (bitmap_weight(trig->pool,
>> +					 CONFIG_IIO_CONSUMERS_PER_TRIGGER)
>> +			   == 1);
>> +		if (trig->set_trigger_state && no_other_users) {
>>  			ret = trig->set_trigger_state(trig, false);
>>  			if (ret)
>>  				goto error_ret;
>> -			spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> +		} else
>> +			ret = 0;
>> +		iio_trigger_put_irq(trig, pf->irq);
>> +		free_irq(pf->irq, pf);
>> +	} else {
>> +		spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> +		list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
>> +			if (pf_cursor == pf) {
>> +				ret = 0;
>> +				break;
>> +			}
>> +		if (!ret) {
>> +			if (list_is_singular(&trig->pollfunc_list)
>> +			    && trig->set_trigger_state) {
>> +				spin_unlock_irqrestore(&trig
>> +						       ->pollfunc_list_lock,
>> +						       flags);
>> +				/* May sleep hence cannot hold the spin lock */
>> +				ret = trig->set_trigger_state(trig, false);
>> +				if (ret)
>> +					goto error_ret;
>> +				spin_lock_irqsave(&trig->pollfunc_list_lock,
>> +						  flags);
>> +			}
>> +			/*
>> +			 * Now we can delete safe in the knowledge that, if
>> +			 * this is the last pollfunc then we have disabled
>> +			 * the trigger anyway and so nothing should be able
>> +			 * to call the pollfunc.
>> +			 */
>> +			list_del(&pf_cursor->list);
>>  		}
>> -		/*
>> -		 * Now we can delete safe in the knowledge that, if this is
>> -		 * the last pollfunc then we have disabled the trigger anyway
>> -		 * and so nothing should be able to call the pollfunc.
>> -		 */
>> -		list_del(&pf_cursor->list);
>> +		spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>>  	}
>> -	spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>>  
>>  error_ret:
>>  	return ret;
>>  }
>>  EXPORT_SYMBOL(iio_trigger_dettach_poll_func);
>>  
>> +irqreturn_t iio_pollfunc_store_time(int irq, void *p)
>> +{
>> +	struct iio_poll_func *pf = p;
>> +	pf->timestamp = iio_get_time_ns();
>> +	return IRQ_WAKE_THREAD;
>> +}
>> +EXPORT_SYMBOL(iio_pollfunc_store_time);
>> +
>>  /**
>>   * iio_trigger_read_currrent() - trigger consumer sysfs query which trigger
>>   *
>> @@ -337,6 +412,22 @@ static const struct attribute_group iio_trigger_consumer_attr_group = {
>>  static void iio_trig_release(struct device *device)
>>  {
>>  	struct iio_trigger *trig = to_iio_trigger(device);
>> +	int i;
>> +
>> +	if (trig->subirq_base) {
>> +		for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
>> +			irq_modify_status(trig->subirq_base + i,
>> +					  IRQ_NOAUTOEN,
>> +					  IRQ_NOREQUEST | IRQ_NOPROBE);
>> +			irq_set_chip(trig->subirq_base + i,
>> +				     NULL);
>> +			irq_set_handler(trig->subirq_base + i,
>> +					NULL);
>> +		}
>> +
>> +		iio_irq_pool_put_range(trig->subirq_base,
>> +				       CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> +	}
>>  	kfree(trig);
>>  	iio_put();
>>  }
>> @@ -345,11 +436,30 @@ static struct device_type iio_trig_type = {
>>  	.release = iio_trig_release,
>>  };
>>  
>> -struct iio_trigger *iio_allocate_trigger(void)
>> +static void iio_trig_subirqmask(struct irq_data *d)
>> +{
>> +	struct irq_chip *chip = irq_data_get_irq_chip(d);
>> +	struct iio_trigger *trig
>> +		= container_of(chip,
>> +			       struct iio_trigger, subirq_chip);
>> +	trig->subirqs[d->irq - trig->subirq_base].enabled = false;
>> +}
>> +
>> +static void iio_trig_subirqunmask(struct irq_data *d)
>> +{
>> +	struct irq_chip *chip = irq_data_get_irq_chip(d);
>> +	struct iio_trigger *trig
>> +		= container_of(chip,
>> +			       struct iio_trigger, subirq_chip);
>> +	trig->subirqs[d->irq - trig->subirq_base].enabled = true;
>> +}
>> +
>> +struct iio_trigger *iio_allocate_trigger_named(const char *name)
>>  {
>>  	struct iio_trigger *trig;
>>  	trig = kzalloc(sizeof *trig, GFP_KERNEL);
>>  	if (trig) {
>> +		int i;
>>  		trig->dev.type = &iio_trig_type;
>>  		trig->dev.bus = &iio_bus_type;
>>  		device_initialize(&trig->dev);
>> @@ -357,10 +467,40 @@ struct iio_trigger *iio_allocate_trigger(void)
>>  		spin_lock_init(&trig->pollfunc_list_lock);
>>  		INIT_LIST_HEAD(&trig->list);
>>  		INIT_LIST_HEAD(&trig->pollfunc_list);
>> +
>> +		if (name) {
>> +			mutex_init(&trig->pool_lock);
>> +			trig->subirq_base
>> +				= iio_irq_pool_get_range(
>> +					CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> +			if (trig->subirq_base < 0) {
>> +				kfree(trig);
>> +				return NULL;
>> +			}
>> +			trig->name = name;
>> +			trig->subirq_chip.name = name;
>> +			trig->subirq_chip.irq_mask = &iio_trig_subirqmask;
>> +			trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask;
>> +			for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
>> +				irq_set_chip(trig->subirq_base + i,
>> +					     &trig->subirq_chip);
>> +				irq_set_handler(trig->subirq_base + i,
>> +						&handle_simple_irq);
>> +				irq_modify_status(trig->subirq_base + i,
>> +						  IRQ_NOREQUEST | IRQ_NOAUTOEN,
>> +						  IRQ_NOPROBE);
>> +			}
>> +		}
>>  		iio_get();
>>  	}
>>  	return trig;
>>  }
>> +EXPORT_SYMBOL(iio_allocate_trigger_named);
>> +
>> +struct iio_trigger *iio_allocate_trigger(void)
>> +{
>> +	return iio_allocate_trigger_named(NULL);
>> +}
>>  EXPORT_SYMBOL(iio_allocate_trigger);
>>  
>>  void iio_free_trigger(struct iio_trigger *trig)
>> diff --git a/drivers/staging/iio/trigger.h b/drivers/staging/iio/trigger.h
>> index c6ab32f..0c44c5e 100644
>> --- a/drivers/staging/iio/trigger.h
>> +++ b/drivers/staging/iio/trigger.h
>> @@ -6,9 +6,15 @@
>>   * under the terms of the GNU General Public License version 2 as published by
>>   * the Free Software Foundation.
>>   */
>> +#include <linux/irq.h>
>> +
>>  #ifndef _IIO_TRIGGER_H_
>>  #define _IIO_TRIGGER_H_
>>  
>> +struct iio_subirq {
>> +	bool enabled;
>> +};
>> +
>>  /**
>>   * struct iio_trigger - industrial I/O trigger device
>>   *
>> @@ -43,6 +49,13 @@ struct iio_trigger {
>>  
>>  	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
>>  	int (*try_reenable)(struct iio_trigger *trig);
>> +
>> +	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;
>>  };
>>  
>>  static inline struct iio_trigger *to_iio_trigger(struct device *d)
>> @@ -114,6 +127,27 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
>>  void iio_trigger_poll(struct iio_trigger *trig, s64 time);
>>  void iio_trigger_notify_done(struct iio_trigger *trig);
>>  
>> +static inline int iio_trigger_get_irq(struct iio_trigger *trig)
>> +{
>> +	int ret;
>> +	mutex_lock(&trig->pool_lock);
>> +	ret = bitmap_find_free_region(trig->pool,
>> +				      CONFIG_IIO_CONSUMERS_PER_TRIGGER,
>> +				      ilog2(1));
>> +	mutex_unlock(&trig->pool_lock);
>> +	if (ret >= 0)
>> +		ret += trig->subirq_base;
>> +
>> +	return ret;
>> +};
>> +
>> +static inline void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
>> +{
>> +	mutex_lock(&trig->pool_lock);
>> +	clear_bit(irq - trig->subirq_base, trig->pool);
>> +	mutex_unlock(&trig->pool_lock);
>> +};
>> +
>>  /**
>>   * struct iio_poll_func - poll function pair
>>   *
>> @@ -125,11 +159,14 @@ void iio_trigger_notify_done(struct iio_trigger *trig);
>>   * @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 is only important when multiple sensors are
>> - * being triggered by a single trigger. This really comes into its own with
>> - * simultaneous sampling devices where a simple latch command can be used to
>> - * make the device store the values on all inputs.
>> + * @h:				the function that is actually run on trigger
>> + * @thread:			threaded interrupt part
>> + * @type:			the type of interrupt (basically if oneshot)
>> + * @irq:			the corresponding irq as allocated from the
>> + *				trigger pool
>> + * @timestamp:			some devices need a timestamp grabbed as soon
>> + *				as possible after the trigger - hence handler
>> + *				passes it via here.
>>   **/
>>  struct iio_poll_func {
>>  	struct				list_head list;
>> @@ -137,12 +174,20 @@ struct iio_poll_func {
>>  	void (*poll_func_immediate)(struct iio_dev *indio_dev);
>>  	void (*poll_func_main)(struct iio_dev *private_data, s64 time);
>>  
>> +	irqreturn_t (*h)(int irq, void *p);
>> +	irqreturn_t (*thread)(int irq, void *p);
>> +	int type;
>> +	char *name;
>> +	int irq;
>> +	s64 timestamp;
>>  };
>>  
>>  int iio_alloc_pollfunc(struct iio_dev *indio_dev,
>>  		       void (*immediate)(struct iio_dev *indio_dev),
>>  		       void (*main)(struct iio_dev *private_data, s64 time));
>>  
>> +irqreturn_t iio_pollfunc_store_time(int irq, void *p);
>> +
>>  /*
>>   * Two functions for common case where all that happens is a pollfunc
>>   * is attached and detached from a trigger
>> @@ -151,7 +196,7 @@ int iio_triggered_ring_postenable(struct iio_dev *indio_dev);
>>  int iio_triggered_ring_predisable(struct iio_dev *indio_dev);
>>  
>>  struct iio_trigger *iio_allocate_trigger(void);
>> -
>> +struct iio_trigger *iio_allocate_trigger_named(const char *name);
>>  void iio_free_trigger(struct iio_trigger *trig);
>>  
>>  #endif /* _IIO_TRIGGER_H_ */
> 
>