OpenCloudOS-Kernel/drivers/iio/industrialio-trigger.c

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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.
*/
#include <linux/kernel.h>
#include <linux/idr.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/list.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include "iio_core.h"
#include "iio_core_trigger.h"
#include <linux/iio/trigger_consumer.h>
/* RFC - Question of approach
* Make the common case (single sensor single trigger)
* simple by starting trigger capture from when first sensors
* is added.
*
* Complex simultaneous start requires use of 'hold' functionality
* of the trigger. (not implemented)
*
* Any other suggestions?
*/
static DEFINE_IDA(iio_trigger_ida);
/* Single list of all available triggers */
static LIST_HEAD(iio_trigger_list);
static DEFINE_MUTEX(iio_trigger_list_lock);
/**
* iio_trigger_read_name() - retrieve useful identifying name
**/
static ssize_t iio_trigger_read_name(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_trigger *trig = to_iio_trigger(dev);
return sprintf(buf, "%s\n", trig->name);
}
static DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
static struct attribute *iio_trig_dev_attrs[] = {
&dev_attr_name.attr,
NULL,
};
static struct attribute_group iio_trig_attr_group = {
.attrs = iio_trig_dev_attrs,
};
static const struct attribute_group *iio_trig_attr_groups[] = {
&iio_trig_attr_group,
NULL
};
int iio_trigger_register(struct iio_trigger *trig_info)
{
int ret;
trig_info->id = ida_simple_get(&iio_trigger_ida, 0, 0, GFP_KERNEL);
if (trig_info->id < 0) {
ret = trig_info->id;
goto error_ret;
}
/* Set the name used for the sysfs directory etc */
dev_set_name(&trig_info->dev, "trigger%ld",
(unsigned long) trig_info->id);
ret = device_add(&trig_info->dev);
if (ret)
goto error_unregister_id;
/* Add to list of available triggers held by the IIO core */
mutex_lock(&iio_trigger_list_lock);
list_add_tail(&trig_info->list, &iio_trigger_list);
mutex_unlock(&iio_trigger_list_lock);
return 0;
error_unregister_id:
ida_simple_remove(&iio_trigger_ida, trig_info->id);
error_ret:
return ret;
}
EXPORT_SYMBOL(iio_trigger_register);
void iio_trigger_unregister(struct iio_trigger *trig_info)
{
mutex_lock(&iio_trigger_list_lock);
list_del(&trig_info->list);
mutex_unlock(&iio_trigger_list_lock);
ida_simple_remove(&iio_trigger_ida, trig_info->id);
/* Possible issue in here */
device_unregister(&trig_info->dev);
}
EXPORT_SYMBOL(iio_trigger_unregister);
static struct iio_trigger *iio_trigger_find_by_name(const char *name,
size_t len)
{
struct iio_trigger *trig = NULL, *iter;
mutex_lock(&iio_trigger_list_lock);
list_for_each_entry(iter, &iio_trigger_list, list)
if (sysfs_streq(iter->name, name)) {
trig = iter;
break;
}
mutex_unlock(&iio_trigger_list_lock);
return trig;
}
void iio_trigger_poll(struct iio_trigger *trig, s64 time)
{
int i;
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);
irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private)
{
iio_trigger_poll(private, iio_get_time_ns());
return IRQ_HANDLED;
}
EXPORT_SYMBOL(iio_trigger_generic_data_rdy_poll);
void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time)
{
int i;
if (!trig->use_count)
for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
if (trig->subirqs[i].enabled) {
trig->use_count++;
handle_nested_irq(trig->subirq_base + i);
}
}
EXPORT_SYMBOL(iio_trigger_poll_chained);
void iio_trigger_notify_done(struct iio_trigger *trig)
{
trig->use_count--;
if (trig->use_count == 0 && trig->ops && trig->ops->try_reenable)
if (trig->ops->try_reenable(trig))
/* Missed an interrupt so launch new poll now */
iio_trigger_poll(trig, 0);
}
EXPORT_SYMBOL(iio_trigger_notify_done);
/* Trigger Consumer related functions */
static 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 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);
}
/* Complexity in here. With certain triggers (datardy) an acknowledgement
* may be needed if the pollfuncs do not include the data read for the
* triggering device.
* This is not currently handled. Alternative of not enabling trigger unless
* the relevant function is in there may be the best option.
*/
/* Worth protecting against double additions? */
static int iio_trigger_attach_poll_func(struct iio_trigger *trig,
struct iio_poll_func *pf)
{
int ret = 0;
bool notinuse
= bitmap_empty(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
/* Prevent the module from being removed whilst attached to a trigger */
__module_get(pf->indio_dev->info->driver_module);
pf->irq = iio_trigger_get_irq(trig);
ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
pf->type, pf->name,
pf);
if (ret < 0) {
module_put(pf->indio_dev->info->driver_module);
return ret;
}
if (trig->ops && trig->ops->set_trigger_state && notinuse) {
ret = trig->ops->set_trigger_state(trig, true);
if (ret < 0)
module_put(pf->indio_dev->info->driver_module);
}
return ret;
}
static int iio_trigger_detach_poll_func(struct iio_trigger *trig,
struct iio_poll_func *pf)
{
int ret = 0;
bool no_other_users
= (bitmap_weight(trig->pool,
CONFIG_IIO_CONSUMERS_PER_TRIGGER)
== 1);
if (trig->ops && trig->ops->set_trigger_state && no_other_users) {
ret = trig->ops->set_trigger_state(trig, false);
if (ret)
goto error_ret;
}
iio_trigger_put_irq(trig, pf->irq);
free_irq(pf->irq, pf);
module_put(pf->indio_dev->info->driver_module);
error_ret:
return ret;
}
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);
struct iio_poll_func
*iio_alloc_pollfunc(irqreturn_t (*h)(int irq, void *p),
irqreturn_t (*thread)(int irq, void *p),
int type,
struct iio_dev *indio_dev,
const char *fmt,
...)
{
va_list vargs;
struct iio_poll_func *pf;
pf = kmalloc(sizeof *pf, GFP_KERNEL);
if (pf == NULL)
return NULL;
va_start(vargs, fmt);
pf->name = kvasprintf(GFP_KERNEL, fmt, vargs);
va_end(vargs);
if (pf->name == NULL) {
kfree(pf);
return NULL;
}
pf->h = h;
pf->thread = thread;
pf->type = type;
pf->indio_dev = indio_dev;
return pf;
}
EXPORT_SYMBOL_GPL(iio_alloc_pollfunc);
void iio_dealloc_pollfunc(struct iio_poll_func *pf)
{
kfree(pf->name);
kfree(pf);
}
EXPORT_SYMBOL_GPL(iio_dealloc_pollfunc);
/**
* iio_trigger_read_current() - trigger consumer sysfs query current trigger
*
* For trigger consumers the current_trigger interface allows the trigger
* used by the device to be queried.
**/
static ssize_t iio_trigger_read_current(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
if (indio_dev->trig)
return sprintf(buf, "%s\n", indio_dev->trig->name);
return 0;
}
/**
* iio_trigger_write_current() - trigger consumer sysfs set current trigger
*
* For trigger consumers the current_trigger interface allows the trigger
* used for this device to be specified at run time based on the triggers
* name.
**/
static ssize_t iio_trigger_write_current(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct iio_trigger *oldtrig = indio_dev->trig;
struct iio_trigger *trig;
int ret;
mutex_lock(&indio_dev->mlock);
if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
mutex_unlock(&indio_dev->mlock);
return -EBUSY;
}
mutex_unlock(&indio_dev->mlock);
trig = iio_trigger_find_by_name(buf, len);
if (oldtrig == trig)
return len;
if (trig && indio_dev->info->validate_trigger) {
ret = indio_dev->info->validate_trigger(indio_dev, trig);
if (ret)
return ret;
}
if (trig && trig->ops && trig->ops->validate_device) {
ret = trig->ops->validate_device(trig, indio_dev);
if (ret)
return ret;
}
indio_dev->trig = trig;
if (oldtrig && indio_dev->trig != oldtrig)
iio_trigger_put(oldtrig);
if (indio_dev->trig)
iio_trigger_get(indio_dev->trig);
return len;
}
static DEVICE_ATTR(current_trigger, S_IRUGO | S_IWUSR,
iio_trigger_read_current,
iio_trigger_write_current);
static struct attribute *iio_trigger_consumer_attrs[] = {
&dev_attr_current_trigger.attr,
NULL,
};
static const struct attribute_group iio_trigger_consumer_attr_group = {
.name = "trigger",
.attrs = iio_trigger_consumer_attrs,
};
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);
}
irq_free_descs(trig->subirq_base,
CONFIG_IIO_CONSUMERS_PER_TRIGGER);
}
kfree(trig->name);
kfree(trig);
}
static struct device_type iio_trig_type = {
.release = iio_trig_release,
.groups = iio_trig_attr_groups,
};
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_trigger_alloc(const char *fmt, ...)
{
va_list vargs;
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);
mutex_init(&trig->pool_lock);
trig->subirq_base
= irq_alloc_descs(-1, 0,
CONFIG_IIO_CONSUMERS_PER_TRIGGER,
0);
if (trig->subirq_base < 0) {
kfree(trig);
return NULL;
}
va_start(vargs, fmt);
trig->name = kvasprintf(GFP_KERNEL, fmt, vargs);
va_end(vargs);
if (trig->name == NULL) {
irq_free_descs(trig->subirq_base,
CONFIG_IIO_CONSUMERS_PER_TRIGGER);
kfree(trig);
return NULL;
}
trig->subirq_chip.name = trig->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);
}
get_device(&trig->dev);
}
return trig;
}
EXPORT_SYMBOL(iio_trigger_alloc);
void iio_trigger_free(struct iio_trigger *trig)
{
if (trig)
put_device(&trig->dev);
}
EXPORT_SYMBOL(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);