mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-28 20:02:17 +00:00
![Dmitry Torokhov](/assets/img/avatar_default.png)
Managed resources are becoming more and more popular in drivers. Let's implement managed polled input devices, to complement managed regular input devices. Similarly to managed regular input devices only one new call devm_input_allocate_polled_device() is added and the rest of APIs is modified to work with both managed and non-managed devices. Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Tested-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
366 lines
9.3 KiB
C
366 lines
9.3 KiB
C
/*
|
|
* Generic implementation of a polled input device
|
|
|
|
* Copyright (c) 2007 Dmitry Torokhov
|
|
*
|
|
* 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 pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/jiffies.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/module.h>
|
|
#include <linux/input-polldev.h>
|
|
|
|
MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
|
|
MODULE_DESCRIPTION("Generic implementation of a polled input device");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_VERSION("0.1");
|
|
|
|
static void input_polldev_queue_work(struct input_polled_dev *dev)
|
|
{
|
|
unsigned long delay;
|
|
|
|
delay = msecs_to_jiffies(dev->poll_interval);
|
|
if (delay >= HZ)
|
|
delay = round_jiffies_relative(delay);
|
|
|
|
queue_delayed_work(system_freezable_wq, &dev->work, delay);
|
|
}
|
|
|
|
static void input_polled_device_work(struct work_struct *work)
|
|
{
|
|
struct input_polled_dev *dev =
|
|
container_of(work, struct input_polled_dev, work.work);
|
|
|
|
dev->poll(dev);
|
|
input_polldev_queue_work(dev);
|
|
}
|
|
|
|
static int input_open_polled_device(struct input_dev *input)
|
|
{
|
|
struct input_polled_dev *dev = input_get_drvdata(input);
|
|
|
|
if (dev->open)
|
|
dev->open(dev);
|
|
|
|
/* Only start polling if polling is enabled */
|
|
if (dev->poll_interval > 0) {
|
|
dev->poll(dev);
|
|
input_polldev_queue_work(dev);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void input_close_polled_device(struct input_dev *input)
|
|
{
|
|
struct input_polled_dev *dev = input_get_drvdata(input);
|
|
|
|
cancel_delayed_work_sync(&dev->work);
|
|
|
|
if (dev->close)
|
|
dev->close(dev);
|
|
}
|
|
|
|
/* SYSFS interface */
|
|
|
|
static ssize_t input_polldev_get_poll(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct input_polled_dev *polldev = dev_get_drvdata(dev);
|
|
|
|
return sprintf(buf, "%d\n", polldev->poll_interval);
|
|
}
|
|
|
|
static ssize_t input_polldev_set_poll(struct device *dev,
|
|
struct device_attribute *attr, const char *buf,
|
|
size_t count)
|
|
{
|
|
struct input_polled_dev *polldev = dev_get_drvdata(dev);
|
|
struct input_dev *input = polldev->input;
|
|
unsigned int interval;
|
|
int err;
|
|
|
|
err = kstrtouint(buf, 0, &interval);
|
|
if (err)
|
|
return err;
|
|
|
|
if (interval < polldev->poll_interval_min)
|
|
return -EINVAL;
|
|
|
|
if (interval > polldev->poll_interval_max)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&input->mutex);
|
|
|
|
polldev->poll_interval = interval;
|
|
|
|
if (input->users) {
|
|
cancel_delayed_work_sync(&polldev->work);
|
|
if (polldev->poll_interval > 0)
|
|
input_polldev_queue_work(polldev);
|
|
}
|
|
|
|
mutex_unlock(&input->mutex);
|
|
|
|
return count;
|
|
}
|
|
|
|
static DEVICE_ATTR(poll, S_IRUGO | S_IWUSR, input_polldev_get_poll,
|
|
input_polldev_set_poll);
|
|
|
|
|
|
static ssize_t input_polldev_get_max(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct input_polled_dev *polldev = dev_get_drvdata(dev);
|
|
|
|
return sprintf(buf, "%d\n", polldev->poll_interval_max);
|
|
}
|
|
|
|
static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL);
|
|
|
|
static ssize_t input_polldev_get_min(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct input_polled_dev *polldev = dev_get_drvdata(dev);
|
|
|
|
return sprintf(buf, "%d\n", polldev->poll_interval_min);
|
|
}
|
|
|
|
static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL);
|
|
|
|
static struct attribute *sysfs_attrs[] = {
|
|
&dev_attr_poll.attr,
|
|
&dev_attr_max.attr,
|
|
&dev_attr_min.attr,
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group input_polldev_attribute_group = {
|
|
.attrs = sysfs_attrs
|
|
};
|
|
|
|
static const struct attribute_group *input_polldev_attribute_groups[] = {
|
|
&input_polldev_attribute_group,
|
|
NULL
|
|
};
|
|
|
|
/**
|
|
* input_allocate_polled_device - allocate memory for polled device
|
|
*
|
|
* The function allocates memory for a polled device and also
|
|
* for an input device associated with this polled device.
|
|
*/
|
|
struct input_polled_dev *input_allocate_polled_device(void)
|
|
{
|
|
struct input_polled_dev *dev;
|
|
|
|
dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL);
|
|
if (!dev)
|
|
return NULL;
|
|
|
|
dev->input = input_allocate_device();
|
|
if (!dev->input) {
|
|
kfree(dev);
|
|
return NULL;
|
|
}
|
|
|
|
return dev;
|
|
}
|
|
EXPORT_SYMBOL(input_allocate_polled_device);
|
|
|
|
struct input_polled_devres {
|
|
struct input_polled_dev *polldev;
|
|
};
|
|
|
|
static int devm_input_polldev_match(struct device *dev, void *res, void *data)
|
|
{
|
|
struct input_polled_devres *devres = res;
|
|
|
|
return devres->polldev == data;
|
|
}
|
|
|
|
static void devm_input_polldev_release(struct device *dev, void *res)
|
|
{
|
|
struct input_polled_devres *devres = res;
|
|
struct input_polled_dev *polldev = devres->polldev;
|
|
|
|
dev_dbg(dev, "%s: dropping reference/freeing %s\n",
|
|
__func__, dev_name(&polldev->input->dev));
|
|
|
|
input_put_device(polldev->input);
|
|
kfree(polldev);
|
|
}
|
|
|
|
static void devm_input_polldev_unregister(struct device *dev, void *res)
|
|
{
|
|
struct input_polled_devres *devres = res;
|
|
struct input_polled_dev *polldev = devres->polldev;
|
|
|
|
dev_dbg(dev, "%s: unregistering device %s\n",
|
|
__func__, dev_name(&polldev->input->dev));
|
|
input_unregister_device(polldev->input);
|
|
|
|
/*
|
|
* Note that we are still holding extra reference to the input
|
|
* device so it will stick around until devm_input_polldev_release()
|
|
* is called.
|
|
*/
|
|
}
|
|
|
|
/**
|
|
* devm_input_allocate_polled_device - allocate managed polled device
|
|
* @dev: device owning the polled device being created
|
|
*
|
|
* Returns prepared &struct input_polled_dev or %NULL.
|
|
*
|
|
* Managed polled input devices do not need to be explicitly unregistered
|
|
* or freed as it will be done automatically when owner device unbinds
|
|
* from * its driver (or binding fails). Once such managed polled device
|
|
* is allocated, it is ready to be set up and registered in the same
|
|
* fashion as regular polled input devices (using
|
|
* input_register_polled_device() function).
|
|
*
|
|
* If you want to manually unregister and free such managed polled devices,
|
|
* it can be still done by calling input_unregister_polled_device() and
|
|
* input_free_polled_device(), although it is rarely needed.
|
|
*
|
|
* NOTE: the owner device is set up as parent of input device and users
|
|
* should not override it.
|
|
*/
|
|
struct input_polled_dev *devm_input_allocate_polled_device(struct device *dev)
|
|
{
|
|
struct input_polled_dev *polldev;
|
|
struct input_polled_devres *devres;
|
|
|
|
devres = devres_alloc(devm_input_polldev_release, sizeof(*devres),
|
|
GFP_KERNEL);
|
|
if (!devres)
|
|
return NULL;
|
|
|
|
polldev = input_allocate_polled_device();
|
|
if (!polldev) {
|
|
devres_free(devres);
|
|
return NULL;
|
|
}
|
|
|
|
polldev->input->dev.parent = dev;
|
|
polldev->devres_managed = true;
|
|
|
|
devres->polldev = polldev;
|
|
devres_add(dev, devres);
|
|
|
|
return polldev;
|
|
}
|
|
EXPORT_SYMBOL(devm_input_allocate_polled_device);
|
|
|
|
/**
|
|
* input_free_polled_device - free memory allocated for polled device
|
|
* @dev: device to free
|
|
*
|
|
* The function frees memory allocated for polling device and drops
|
|
* reference to the associated input device.
|
|
*/
|
|
void input_free_polled_device(struct input_polled_dev *dev)
|
|
{
|
|
if (dev) {
|
|
if (dev->devres_managed)
|
|
WARN_ON(devres_destroy(dev->input->dev.parent,
|
|
devm_input_polldev_release,
|
|
devm_input_polldev_match,
|
|
dev));
|
|
input_put_device(dev->input);
|
|
kfree(dev);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(input_free_polled_device);
|
|
|
|
/**
|
|
* input_register_polled_device - register polled device
|
|
* @dev: device to register
|
|
*
|
|
* The function registers previously initialized polled input device
|
|
* with input layer. The device should be allocated with call to
|
|
* input_allocate_polled_device(). Callers should also set up poll()
|
|
* method and set up capabilities (id, name, phys, bits) of the
|
|
* corresponding input_dev structure.
|
|
*/
|
|
int input_register_polled_device(struct input_polled_dev *dev)
|
|
{
|
|
struct input_polled_devres *devres = NULL;
|
|
struct input_dev *input = dev->input;
|
|
int error;
|
|
|
|
if (dev->devres_managed) {
|
|
devres = devres_alloc(devm_input_polldev_unregister,
|
|
sizeof(*devres), GFP_KERNEL);
|
|
if (!devres)
|
|
return -ENOMEM;
|
|
|
|
devres->polldev = dev;
|
|
}
|
|
|
|
input_set_drvdata(input, dev);
|
|
INIT_DELAYED_WORK(&dev->work, input_polled_device_work);
|
|
|
|
if (!dev->poll_interval)
|
|
dev->poll_interval = 500;
|
|
if (!dev->poll_interval_max)
|
|
dev->poll_interval_max = dev->poll_interval;
|
|
|
|
input->open = input_open_polled_device;
|
|
input->close = input_close_polled_device;
|
|
|
|
input->dev.groups = input_polldev_attribute_groups;
|
|
|
|
error = input_register_device(input);
|
|
if (error) {
|
|
devres_free(devres);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Take extra reference to the underlying input device so
|
|
* that it survives call to input_unregister_polled_device()
|
|
* and is deleted only after input_free_polled_device()
|
|
* has been invoked. This is needed to ease task of freeing
|
|
* sparse keymaps.
|
|
*/
|
|
input_get_device(input);
|
|
|
|
if (dev->devres_managed) {
|
|
dev_dbg(input->dev.parent, "%s: registering %s with devres.\n",
|
|
__func__, dev_name(&input->dev));
|
|
devres_add(input->dev.parent, devres);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(input_register_polled_device);
|
|
|
|
/**
|
|
* input_unregister_polled_device - unregister polled device
|
|
* @dev: device to unregister
|
|
*
|
|
* The function unregisters previously registered polled input
|
|
* device from input layer. Polling is stopped and device is
|
|
* ready to be freed with call to input_free_polled_device().
|
|
*/
|
|
void input_unregister_polled_device(struct input_polled_dev *dev)
|
|
{
|
|
if (dev->devres_managed)
|
|
WARN_ON(devres_destroy(dev->input->dev.parent,
|
|
devm_input_polldev_unregister,
|
|
devm_input_polldev_match,
|
|
dev));
|
|
|
|
input_unregister_device(dev->input);
|
|
}
|
|
EXPORT_SYMBOL(input_unregister_polled_device);
|