[linux-2.6-block.git] / drivers / input / input-polldev.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Generic implementation of a polled input device

 * Copyright (c) 2007 Dmitry Torokhov
 */

#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");

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);
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
0dcd8073 DT	2	/*
	3	* Generic implementation of a polled input device
	4
	5	* Copyright (c) 2007 Dmitry Torokhov
0dcd8073 DT	6	*/
0dcd8073 DT	7
da0c4901 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
da0c4901 JP	9
0dcd8073	10	#include <linux/jiffies.h>
5a0e3ad6	11	#include <linux/slab.h>
0dcd8073	12	#include <linux/mutex.h>
e490ebdc	13	#include <linux/workqueue.h>
d2d8442d	14	#include <linux/module.h>
0dcd8073 DT	15	#include <linux/input-polldev.h>
0dcd8073 DT	16
36bd52a4 EP	17	MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
	18	MODULE_DESCRIPTION("Generic implementation of a polled input device");
	19	MODULE_LICENSE("GPL v2");
36bd52a4	20
dad725d0	21	static void input_polldev_queue_work(struct input_polled_dev *dev)
0dcd8073	22	{
374766bc	23	unsigned long delay;
0dcd8073	24
374766bc SH	25	delay = msecs_to_jiffies(dev->poll_interval);
	26	if (delay >= HZ)
	27	delay = round_jiffies_relative(delay);
	28
e490ebdc	29	queue_delayed_work(system_freezable_wq, &dev->work, delay);
0dcd8073 DT	30	}
0dcd8073 DT	31
dad725d0 SO	32	static void input_polled_device_work(struct work_struct *work)
	33	{
	34	struct input_polled_dev *dev =
	35	container_of(work, struct input_polled_dev, work.work);
	36
	37	dev->poll(dev);
	38	input_polldev_queue_work(dev);
	39	}
	40
0dcd8073 DT	41	static int input_open_polled_device(struct input_dev *input)
0dcd8073 DT	42	{
3797fec1	43	struct input_polled_dev *dev = input_get_drvdata(input);
0dcd8073	44
b0aba1e6 SO	45	if (dev->open)
b0aba1e6 SO	46	dev->open(dev);
0dcd8073	47
11bb4cc7	48	/* Only start polling if polling is enabled */
5e3e4eb1 DT	49	if (dev->poll_interval > 0) {
	50	dev->poll(dev);
	51	input_polldev_queue_work(dev);
	52	}
0dcd8073 DT	53
	54	return 0;
	55	}
	56
	57	static void input_close_polled_device(struct input_dev *input)
	58	{
3797fec1	59	struct input_polled_dev *dev = input_get_drvdata(input);
0dcd8073	60
374766bc	61	cancel_delayed_work_sync(&dev->work);
b0aba1e6 SO	62
	63	if (dev->close)
	64	dev->close(dev);
0dcd8073 DT	65	}
0dcd8073 DT	66
dad725d0 SO	67	/* SYSFS interface */
	68
	69	static ssize_t input_polldev_get_poll(struct device *dev,
	70	struct device_attribute attr, char buf)
	71	{
	72	struct input_polled_dev *polldev = dev_get_drvdata(dev);
	73
	74	return sprintf(buf, "%d\n", polldev->poll_interval);
	75	}
	76
	77	static ssize_t input_polldev_set_poll(struct device *dev,
	78	struct device_attribute attr, const char buf,
	79	size_t count)
	80	{
	81	struct input_polled_dev *polldev = dev_get_drvdata(dev);
	82	struct input_dev *input = polldev->input;
76496e7a JD	83	unsigned int interval;
76496e7a JD	84	int err;
dad725d0	85
76496e7a JD	86	err = kstrtouint(buf, 0, &interval);
	87	if (err)
	88	return err;
dad725d0 SO	89
	90	if (interval < polldev->poll_interval_min)
	91	return -EINVAL;
	92
	93	if (interval > polldev->poll_interval_max)
	94	return -EINVAL;
	95
	96	mutex_lock(&input->mutex);
	97
	98	polldev->poll_interval = interval;
	99
	100	if (input->users) {
	101	cancel_delayed_work_sync(&polldev->work);
	102	if (polldev->poll_interval > 0)
	103	input_polldev_queue_work(polldev);
	104	}
	105
	106	mutex_unlock(&input->mutex);
	107
	108	return count;
	109	}
	110
	111	static DEVICE_ATTR(poll, S_IRUGO \| S_IWUSR, input_polldev_get_poll,
	112	input_polldev_set_poll);
	113
	114
	115	static ssize_t input_polldev_get_max(struct device *dev,
	116	struct device_attribute attr, char buf)
	117	{
	118	struct input_polled_dev *polldev = dev_get_drvdata(dev);
	119
	120	return sprintf(buf, "%d\n", polldev->poll_interval_max);
	121	}
	122
	123	static DEVICE_ATTR(max, S_IRUGO, input_polldev_get_max, NULL);
	124
	125	static ssize_t input_polldev_get_min(struct device *dev,
	126	struct device_attribute attr, char buf)
	127	{
	128	struct input_polled_dev *polldev = dev_get_drvdata(dev);
	129
	130	return sprintf(buf, "%d\n", polldev->poll_interval_min);
	131	}
	132
	133	static DEVICE_ATTR(min, S_IRUGO, input_polldev_get_min, NULL);
	134
	135	static struct attribute *sysfs_attrs[] = {
	136	&dev_attr_poll.attr,
	137	&dev_attr_max.attr,
	138	&dev_attr_min.attr,
	139	NULL
	140	};
	141
	142	static struct attribute_group input_polldev_attribute_group = {
	143	.attrs = sysfs_attrs
	144	};
	145
d1fefd5b DT	146	static const struct attribute_group *input_polldev_attribute_groups[] = {
	147	&input_polldev_attribute_group,
	148	NULL
	149	};
	150
0dcd8073	151	/**
2546bcc2	152	* input_allocate_polled_device - allocate memory for polled device
0dcd8073 DT	153	*
	154	* The function allocates memory for a polled device and also
	155	* for an input device associated with this polled device.
	156	*/
	157	struct input_polled_dev *input_allocate_polled_device(void)
	158	{
	159	struct input_polled_dev *dev;
	160
	161	dev = kzalloc(sizeof(struct input_polled_dev), GFP_KERNEL);
	162	if (!dev)
	163	return NULL;
	164
	165	dev->input = input_allocate_device();
	166	if (!dev->input) {
	167	kfree(dev);
	168	return NULL;
	169	}
	170
	171	return dev;
	172	}
	173	EXPORT_SYMBOL(input_allocate_polled_device);
	174
bf1de976 DT	175	struct input_polled_devres {
	176	struct input_polled_dev *polldev;
	177	};
	178
	179	static int devm_input_polldev_match(struct device dev, void res, void *data)
	180	{
	181	struct input_polled_devres *devres = res;
	182
	183	return devres->polldev == data;
	184	}
	185
	186	static void devm_input_polldev_release(struct device dev, void res)
	187	{
	188	struct input_polled_devres *devres = res;
	189	struct input_polled_dev *polldev = devres->polldev;
	190
	191	dev_dbg(dev, "%s: dropping reference/freeing %s\n",
	192	__func__, dev_name(&polldev->input->dev));
	193
	194	input_put_device(polldev->input);
	195	kfree(polldev);
	196	}
	197
	198	static void devm_input_polldev_unregister(struct device dev, void res)
	199	{
	200	struct input_polled_devres *devres = res;
	201	struct input_polled_dev *polldev = devres->polldev;
	202
	203	dev_dbg(dev, "%s: unregistering device %s\n",
	204	__func__, dev_name(&polldev->input->dev));
	205	input_unregister_device(polldev->input);
	206
	207	/*
	208	* Note that we are still holding extra reference to the input
	209	* device so it will stick around until devm_input_polldev_release()
	210	* is called.
	211	*/
	212	}
	213
	214	/**
	215	* devm_input_allocate_polled_device - allocate managed polled device
	216	* @dev: device owning the polled device being created
	217	*
	218	* Returns prepared &struct input_polled_dev or %NULL.
	219	*
	220	* Managed polled input devices do not need to be explicitly unregistered
	221	* or freed as it will be done automatically when owner device unbinds
	222	* from * its driver (or binding fails). Once such managed polled device
	223	* is allocated, it is ready to be set up and registered in the same
	224	* fashion as regular polled input devices (using
	225	* input_register_polled_device() function).
	226	*
	227	* If you want to manually unregister and free such managed polled devices,
	228	* it can be still done by calling input_unregister_polled_device() and
	229	* input_free_polled_device(), although it is rarely needed.
	230	*
	231	* NOTE: the owner device is set up as parent of input device and users
	232	* should not override it.
	233	*/
	234	struct input_polled_dev devm_input_allocate_polled_device(struct device dev)
	235	{
	236	struct input_polled_dev *polldev;
	237	struct input_polled_devres *devres;
	238
239	devres = devres_alloc(devm_input_polldev_release, sizeof(*devres),
240	GFP_KERNEL);
241	if (!devres)
242	return NULL;
243
244	polldev = input_allocate_polled_device();
245	if (!polldev) {
246	devres_free(devres);
247	return NULL;
248	}
249
250	polldev->input->dev.parent = dev;
251	polldev->devres_managed = true;
252
253	devres->polldev = polldev;
254	devres_add(dev, devres);
255
256	return polldev;
257	}
258	EXPORT_SYMBOL(devm_input_allocate_polled_device);
259
0dcd8073 DT	260	/**
	261	* input_free_polled_device - free memory allocated for polled device
	262	* @dev: device to free
	263	*
	264	* The function frees memory allocated for polling device and drops
36203c4f	265	* reference to the associated input device.
0dcd8073 DT	266	*/
	267	void input_free_polled_device(struct input_polled_dev *dev)
	268	{
	269	if (dev) {
bf1de976 DT	270	if (dev->devres_managed)
	271	WARN_ON(devres_destroy(dev->input->dev.parent,
	272	devm_input_polldev_release,
	273	devm_input_polldev_match,
	274	dev));
	275	input_put_device(dev->input);
0dcd8073 DT	276	kfree(dev);
	277	}
	278	}
	279	EXPORT_SYMBOL(input_free_polled_device);
	280
	281	/**
	282	* input_register_polled_device - register polled device
	283	* @dev: device to register
	284	*
	285	* The function registers previously initialized polled input device
	286	* with input layer. The device should be allocated with call to
	287	* input_allocate_polled_device(). Callers should also set up poll()
	288	* method and set up capabilities (id, name, phys, bits) of the
2546bcc2	289	* corresponding input_dev structure.
0dcd8073 DT	290	*/
	291	int input_register_polled_device(struct input_polled_dev *dev)
	292	{
bf1de976	293	struct input_polled_devres *devres = NULL;
0dcd8073	294	struct input_dev *input = dev->input;
dad725d0	295	int error;
0dcd8073	296
bf1de976 DT	297	if (dev->devres_managed) {
	298	devres = devres_alloc(devm_input_polldev_unregister,
	299	sizeof(*devres), GFP_KERNEL);
	300	if (!devres)
	301	return -ENOMEM;
	302
	303	devres->polldev = dev;
	304	}
	305
3797fec1	306	input_set_drvdata(input, dev);
0dcd8073	307	INIT_DELAYED_WORK(&dev->work, input_polled_device_work);
d1fefd5b	308
0dcd8073 DT	309	if (!dev->poll_interval)
0dcd8073 DT	310	dev->poll_interval = 500;
dad725d0 SO	311	if (!dev->poll_interval_max)
dad725d0 SO	312	dev->poll_interval_max = dev->poll_interval;
d1fefd5b	313
0dcd8073 DT	314	input->open = input_open_polled_device;
	315	input->close = input_close_polled_device;
	316
d1fefd5b DT	317	input->dev.groups = input_polldev_attribute_groups;
d1fefd5b DT	318
dad725d0	319	error = input_register_device(input);
bf1de976 DT	320	if (error) {
bf1de976 DT	321	devres_free(devres);
dad725d0	322	return error;
bf1de976	323	}
dad725d0	324
36203c4f DT	325	/*
	326	* Take extra reference to the underlying input device so
	327	* that it survives call to input_unregister_polled_device()
	328	* and is deleted only after input_free_polled_device()
	329	* has been invoked. This is needed to ease task of freeing
	330	* sparse keymaps.
	331	*/
	332	input_get_device(input);
	333
bf1de976 DT	334	if (dev->devres_managed) {
	335	dev_dbg(input->dev.parent, "%s: registering %s with devres.\n",
	336	__func__, dev_name(&input->dev));
	337	devres_add(input->dev.parent, devres);
	338	}
	339
dad725d0	340	return 0;
0dcd8073 DT	341	}
	342	EXPORT_SYMBOL(input_register_polled_device);
	343
	344	/**
	345	* input_unregister_polled_device - unregister polled device
	346	* @dev: device to unregister
	347	*
	348	* The function unregisters previously registered polled input
	349	* device from input layer. Polling is stopped and device is
	350	* ready to be freed with call to input_free_polled_device().
0dcd8073 DT	351	*/
	352	void input_unregister_polled_device(struct input_polled_dev *dev)
	353	{
bf1de976 DT	354	if (dev->devres_managed)
	355	WARN_ON(devres_destroy(dev->input->dev.parent,
	356	devm_input_polldev_unregister,
	357	devm_input_polldev_match,
	358	dev));
	359
0dcd8073	360	input_unregister_device(dev->input);
0dcd8073 DT	361	}
0dcd8073 DT	362	EXPORT_SYMBOL(input_unregister_polled_device);