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![Peter Meerwald](/assets/img/avatar_default.png)
argument has been ignored; adjust drivers accordingly Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
583 lines
14 KiB
C
583 lines
14 KiB
C
/* The industrial I/O core, trigger handling functions
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*
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* Copyright (c) 2008 Jonathan Cameron
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*/
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#include <linux/kernel.h>
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#include <linux/idr.h>
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#include <linux/err.h>
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#include <linux/device.h>
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#include <linux/interrupt.h>
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#include <linux/list.h>
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#include <linux/slab.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/trigger.h>
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#include "iio_core.h"
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#include "iio_core_trigger.h"
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#include <linux/iio/trigger_consumer.h>
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/* RFC - Question of approach
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* Make the common case (single sensor single trigger)
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* simple by starting trigger capture from when first sensors
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* is added.
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*
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* Complex simultaneous start requires use of 'hold' functionality
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* of the trigger. (not implemented)
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*
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* Any other suggestions?
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*/
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static DEFINE_IDA(iio_trigger_ida);
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/* Single list of all available triggers */
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static LIST_HEAD(iio_trigger_list);
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static DEFINE_MUTEX(iio_trigger_list_lock);
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/**
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* iio_trigger_read_name() - retrieve useful identifying name
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**/
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static ssize_t iio_trigger_read_name(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct iio_trigger *trig = to_iio_trigger(dev);
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return sprintf(buf, "%s\n", trig->name);
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}
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static DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
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static struct attribute *iio_trig_dev_attrs[] = {
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&dev_attr_name.attr,
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NULL,
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};
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ATTRIBUTE_GROUPS(iio_trig_dev);
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int iio_trigger_register(struct iio_trigger *trig_info)
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{
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int ret;
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trig_info->id = ida_simple_get(&iio_trigger_ida, 0, 0, GFP_KERNEL);
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if (trig_info->id < 0)
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return trig_info->id;
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/* Set the name used for the sysfs directory etc */
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dev_set_name(&trig_info->dev, "trigger%ld",
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(unsigned long) trig_info->id);
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ret = device_add(&trig_info->dev);
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if (ret)
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goto error_unregister_id;
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/* Add to list of available triggers held by the IIO core */
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mutex_lock(&iio_trigger_list_lock);
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list_add_tail(&trig_info->list, &iio_trigger_list);
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mutex_unlock(&iio_trigger_list_lock);
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return 0;
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error_unregister_id:
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ida_simple_remove(&iio_trigger_ida, trig_info->id);
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return ret;
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}
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EXPORT_SYMBOL(iio_trigger_register);
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void iio_trigger_unregister(struct iio_trigger *trig_info)
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{
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mutex_lock(&iio_trigger_list_lock);
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list_del(&trig_info->list);
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mutex_unlock(&iio_trigger_list_lock);
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ida_simple_remove(&iio_trigger_ida, trig_info->id);
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/* Possible issue in here */
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device_del(&trig_info->dev);
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}
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EXPORT_SYMBOL(iio_trigger_unregister);
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static struct iio_trigger *iio_trigger_find_by_name(const char *name,
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size_t len)
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{
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struct iio_trigger *trig = NULL, *iter;
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mutex_lock(&iio_trigger_list_lock);
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list_for_each_entry(iter, &iio_trigger_list, list)
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if (sysfs_streq(iter->name, name)) {
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trig = iter;
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break;
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}
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mutex_unlock(&iio_trigger_list_lock);
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return trig;
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}
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void iio_trigger_poll(struct iio_trigger *trig)
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{
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int i;
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if (!atomic_read(&trig->use_count)) {
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atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
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for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
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if (trig->subirqs[i].enabled)
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generic_handle_irq(trig->subirq_base + i);
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else
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iio_trigger_notify_done(trig);
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}
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}
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}
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EXPORT_SYMBOL(iio_trigger_poll);
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irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private)
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{
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iio_trigger_poll(private);
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return IRQ_HANDLED;
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}
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EXPORT_SYMBOL(iio_trigger_generic_data_rdy_poll);
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void iio_trigger_poll_chained(struct iio_trigger *trig)
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{
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int i;
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if (!atomic_read(&trig->use_count)) {
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atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
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for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
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if (trig->subirqs[i].enabled)
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handle_nested_irq(trig->subirq_base + i);
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else
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iio_trigger_notify_done(trig);
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}
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}
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}
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EXPORT_SYMBOL(iio_trigger_poll_chained);
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void iio_trigger_notify_done(struct iio_trigger *trig)
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{
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if (atomic_dec_and_test(&trig->use_count) && trig->ops &&
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trig->ops->try_reenable)
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if (trig->ops->try_reenable(trig))
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/* Missed an interrupt so launch new poll now */
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iio_trigger_poll(trig);
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}
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EXPORT_SYMBOL(iio_trigger_notify_done);
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/* Trigger Consumer related functions */
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static int iio_trigger_get_irq(struct iio_trigger *trig)
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{
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int ret;
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mutex_lock(&trig->pool_lock);
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ret = bitmap_find_free_region(trig->pool,
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CONFIG_IIO_CONSUMERS_PER_TRIGGER,
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ilog2(1));
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mutex_unlock(&trig->pool_lock);
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if (ret >= 0)
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ret += trig->subirq_base;
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return ret;
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}
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static void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
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{
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mutex_lock(&trig->pool_lock);
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clear_bit(irq - trig->subirq_base, trig->pool);
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mutex_unlock(&trig->pool_lock);
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}
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/* Complexity in here. With certain triggers (datardy) an acknowledgement
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* may be needed if the pollfuncs do not include the data read for the
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* triggering device.
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* This is not currently handled. Alternative of not enabling trigger unless
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* the relevant function is in there may be the best option.
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*/
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/* Worth protecting against double additions? */
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static int iio_trigger_attach_poll_func(struct iio_trigger *trig,
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struct iio_poll_func *pf)
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{
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int ret = 0;
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bool notinuse
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= bitmap_empty(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
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/* Prevent the module from being removed whilst attached to a trigger */
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__module_get(pf->indio_dev->info->driver_module);
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pf->irq = iio_trigger_get_irq(trig);
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ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
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pf->type, pf->name,
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pf);
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if (ret < 0) {
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module_put(pf->indio_dev->info->driver_module);
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return ret;
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}
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if (trig->ops && trig->ops->set_trigger_state && notinuse) {
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ret = trig->ops->set_trigger_state(trig, true);
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if (ret < 0)
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module_put(pf->indio_dev->info->driver_module);
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}
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return ret;
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}
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static int iio_trigger_detach_poll_func(struct iio_trigger *trig,
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struct iio_poll_func *pf)
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{
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int ret = 0;
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bool no_other_users
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= (bitmap_weight(trig->pool,
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CONFIG_IIO_CONSUMERS_PER_TRIGGER)
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== 1);
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if (trig->ops && trig->ops->set_trigger_state && no_other_users) {
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ret = trig->ops->set_trigger_state(trig, false);
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if (ret)
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return ret;
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}
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iio_trigger_put_irq(trig, pf->irq);
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free_irq(pf->irq, pf);
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module_put(pf->indio_dev->info->driver_module);
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return ret;
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}
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irqreturn_t iio_pollfunc_store_time(int irq, void *p)
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{
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struct iio_poll_func *pf = p;
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pf->timestamp = iio_get_time_ns();
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return IRQ_WAKE_THREAD;
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}
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EXPORT_SYMBOL(iio_pollfunc_store_time);
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struct iio_poll_func
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*iio_alloc_pollfunc(irqreturn_t (*h)(int irq, void *p),
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irqreturn_t (*thread)(int irq, void *p),
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int type,
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struct iio_dev *indio_dev,
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const char *fmt,
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...)
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{
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va_list vargs;
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struct iio_poll_func *pf;
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pf = kmalloc(sizeof *pf, GFP_KERNEL);
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if (pf == NULL)
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return NULL;
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va_start(vargs, fmt);
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pf->name = kvasprintf(GFP_KERNEL, fmt, vargs);
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va_end(vargs);
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if (pf->name == NULL) {
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kfree(pf);
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return NULL;
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}
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pf->h = h;
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pf->thread = thread;
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pf->type = type;
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pf->indio_dev = indio_dev;
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return pf;
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}
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EXPORT_SYMBOL_GPL(iio_alloc_pollfunc);
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void iio_dealloc_pollfunc(struct iio_poll_func *pf)
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{
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kfree(pf->name);
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kfree(pf);
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}
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EXPORT_SYMBOL_GPL(iio_dealloc_pollfunc);
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/**
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* iio_trigger_read_current() - trigger consumer sysfs query current trigger
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*
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* For trigger consumers the current_trigger interface allows the trigger
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* used by the device to be queried.
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**/
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static ssize_t iio_trigger_read_current(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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if (indio_dev->trig)
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return sprintf(buf, "%s\n", indio_dev->trig->name);
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return 0;
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}
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/**
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* iio_trigger_write_current() - trigger consumer sysfs set current trigger
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*
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* For trigger consumers the current_trigger interface allows the trigger
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* used for this device to be specified at run time based on the trigger's
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* name.
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**/
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static ssize_t iio_trigger_write_current(struct device *dev,
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struct device_attribute *attr,
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const char *buf,
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size_t len)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct iio_trigger *oldtrig = indio_dev->trig;
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struct iio_trigger *trig;
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int ret;
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mutex_lock(&indio_dev->mlock);
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if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
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mutex_unlock(&indio_dev->mlock);
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return -EBUSY;
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}
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mutex_unlock(&indio_dev->mlock);
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trig = iio_trigger_find_by_name(buf, len);
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if (oldtrig == trig)
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return len;
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if (trig && indio_dev->info->validate_trigger) {
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ret = indio_dev->info->validate_trigger(indio_dev, trig);
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if (ret)
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return ret;
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}
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if (trig && trig->ops && trig->ops->validate_device) {
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ret = trig->ops->validate_device(trig, indio_dev);
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if (ret)
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return ret;
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}
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indio_dev->trig = trig;
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if (oldtrig)
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iio_trigger_put(oldtrig);
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if (indio_dev->trig)
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iio_trigger_get(indio_dev->trig);
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return len;
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}
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static DEVICE_ATTR(current_trigger, S_IRUGO | S_IWUSR,
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iio_trigger_read_current,
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iio_trigger_write_current);
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static struct attribute *iio_trigger_consumer_attrs[] = {
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&dev_attr_current_trigger.attr,
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NULL,
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};
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static const struct attribute_group iio_trigger_consumer_attr_group = {
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.name = "trigger",
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.attrs = iio_trigger_consumer_attrs,
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};
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static void iio_trig_release(struct device *device)
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{
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struct iio_trigger *trig = to_iio_trigger(device);
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int i;
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if (trig->subirq_base) {
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for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
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irq_modify_status(trig->subirq_base + i,
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IRQ_NOAUTOEN,
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IRQ_NOREQUEST | IRQ_NOPROBE);
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irq_set_chip(trig->subirq_base + i,
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NULL);
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irq_set_handler(trig->subirq_base + i,
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NULL);
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}
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irq_free_descs(trig->subirq_base,
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CONFIG_IIO_CONSUMERS_PER_TRIGGER);
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}
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kfree(trig->name);
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kfree(trig);
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}
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static struct device_type iio_trig_type = {
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.release = iio_trig_release,
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.groups = iio_trig_dev_groups,
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};
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static void iio_trig_subirqmask(struct irq_data *d)
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{
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struct irq_chip *chip = irq_data_get_irq_chip(d);
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struct iio_trigger *trig
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= container_of(chip,
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struct iio_trigger, subirq_chip);
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trig->subirqs[d->irq - trig->subirq_base].enabled = false;
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}
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static void iio_trig_subirqunmask(struct irq_data *d)
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{
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struct irq_chip *chip = irq_data_get_irq_chip(d);
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struct iio_trigger *trig
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= container_of(chip,
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struct iio_trigger, subirq_chip);
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trig->subirqs[d->irq - trig->subirq_base].enabled = true;
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}
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static struct iio_trigger *viio_trigger_alloc(const char *fmt, va_list vargs)
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{
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struct iio_trigger *trig;
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trig = kzalloc(sizeof *trig, GFP_KERNEL);
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if (trig) {
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int i;
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trig->dev.type = &iio_trig_type;
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trig->dev.bus = &iio_bus_type;
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device_initialize(&trig->dev);
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mutex_init(&trig->pool_lock);
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trig->subirq_base
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= irq_alloc_descs(-1, 0,
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CONFIG_IIO_CONSUMERS_PER_TRIGGER,
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0);
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if (trig->subirq_base < 0) {
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kfree(trig);
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return NULL;
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}
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trig->name = kvasprintf(GFP_KERNEL, fmt, vargs);
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if (trig->name == NULL) {
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irq_free_descs(trig->subirq_base,
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CONFIG_IIO_CONSUMERS_PER_TRIGGER);
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kfree(trig);
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return NULL;
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}
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trig->subirq_chip.name = trig->name;
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trig->subirq_chip.irq_mask = &iio_trig_subirqmask;
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trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask;
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for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
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irq_set_chip(trig->subirq_base + i,
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&trig->subirq_chip);
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irq_set_handler(trig->subirq_base + i,
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&handle_simple_irq);
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irq_modify_status(trig->subirq_base + i,
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IRQ_NOREQUEST | IRQ_NOAUTOEN,
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IRQ_NOPROBE);
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}
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get_device(&trig->dev);
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}
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return trig;
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}
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struct iio_trigger *iio_trigger_alloc(const char *fmt, ...)
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{
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struct iio_trigger *trig;
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va_list vargs;
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va_start(vargs, fmt);
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trig = viio_trigger_alloc(fmt, vargs);
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va_end(vargs);
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return trig;
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}
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EXPORT_SYMBOL(iio_trigger_alloc);
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void iio_trigger_free(struct iio_trigger *trig)
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{
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if (trig)
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put_device(&trig->dev);
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}
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EXPORT_SYMBOL(iio_trigger_free);
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static void devm_iio_trigger_release(struct device *dev, void *res)
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{
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iio_trigger_free(*(struct iio_trigger **)res);
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}
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static int devm_iio_trigger_match(struct device *dev, void *res, void *data)
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{
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struct iio_trigger **r = res;
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if (!r || !*r) {
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WARN_ON(!r || !*r);
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return 0;
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}
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return *r == data;
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}
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/**
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* devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
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* @dev: Device to allocate iio_trigger for
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* @fmt: trigger name format. If it includes format
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* specifiers, the additional arguments following
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* format are formatted and inserted in the resulting
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* string replacing their respective specifiers.
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*
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* Managed iio_trigger_alloc. iio_trigger allocated with this function is
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* automatically freed on driver detach.
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*
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* If an iio_trigger allocated with this function needs to be freed separately,
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* devm_iio_trigger_free() must be used.
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*
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* RETURNS:
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* Pointer to allocated iio_trigger on success, NULL on failure.
|
|
*/
|
|
struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
|
|
const char *fmt, ...)
|
|
{
|
|
struct iio_trigger **ptr, *trig;
|
|
va_list vargs;
|
|
|
|
ptr = devres_alloc(devm_iio_trigger_release, sizeof(*ptr),
|
|
GFP_KERNEL);
|
|
if (!ptr)
|
|
return NULL;
|
|
|
|
/* use raw alloc_dr for kmalloc caller tracing */
|
|
va_start(vargs, fmt);
|
|
trig = viio_trigger_alloc(fmt, vargs);
|
|
va_end(vargs);
|
|
if (trig) {
|
|
*ptr = trig;
|
|
devres_add(dev, ptr);
|
|
} else {
|
|
devres_free(ptr);
|
|
}
|
|
|
|
return trig;
|
|
}
|
|
EXPORT_SYMBOL_GPL(devm_iio_trigger_alloc);
|
|
|
|
/**
|
|
* devm_iio_trigger_free - Resource-managed iio_trigger_free()
|
|
* @dev: Device this iio_dev belongs to
|
|
* @iio_trig: the iio_trigger associated with the device
|
|
*
|
|
* Free iio_trigger allocated with devm_iio_trigger_alloc().
|
|
*/
|
|
void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig)
|
|
{
|
|
int rc;
|
|
|
|
rc = devres_release(dev, devm_iio_trigger_release,
|
|
devm_iio_trigger_match, iio_trig);
|
|
WARN_ON(rc);
|
|
}
|
|
EXPORT_SYMBOL_GPL(devm_iio_trigger_free);
|
|
|
|
void iio_device_register_trigger_consumer(struct iio_dev *indio_dev)
|
|
{
|
|
indio_dev->groups[indio_dev->groupcounter++] =
|
|
&iio_trigger_consumer_attr_group;
|
|
}
|
|
|
|
void iio_device_unregister_trigger_consumer(struct iio_dev *indio_dev)
|
|
{
|
|
/* Clean up an associated but not attached trigger reference */
|
|
if (indio_dev->trig)
|
|
iio_trigger_put(indio_dev->trig);
|
|
}
|
|
|
|
int iio_triggered_buffer_postenable(struct iio_dev *indio_dev)
|
|
{
|
|
return iio_trigger_attach_poll_func(indio_dev->trig,
|
|
indio_dev->pollfunc);
|
|
}
|
|
EXPORT_SYMBOL(iio_triggered_buffer_postenable);
|
|
|
|
int iio_triggered_buffer_predisable(struct iio_dev *indio_dev)
|
|
{
|
|
return iio_trigger_detach_poll_func(indio_dev->trig,
|
|
indio_dev->pollfunc);
|
|
}
|
|
EXPORT_SYMBOL(iio_triggered_buffer_predisable);
|