Release 4.11 drivers/input/serio/serio.c

/*
 *  The Serio abstraction module
 *
 *  Copyright (c) 1999-2004 Vojtech Pavlik
 *  Copyright (c) 2004 Dmitry Torokhov
 *  Copyright (c) 2003 Daniele Bellucci
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Should you need to contact me, the author, you can do so either by
 * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/serio.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Serio abstraction core");
MODULE_LICENSE("GPL");

/*
 * serio_mutex protects entire serio subsystem and is taken every time
 * serio port or driver registered or unregistered.
 */
static DEFINE_MUTEX(serio_mutex);

static LIST_HEAD(serio_list);

static void serio_add_port(struct serio *serio);
static int serio_reconnect_port(struct serio *serio);
static void serio_disconnect_port(struct serio *serio);
static void serio_reconnect_subtree(struct serio *serio);
static void serio_attach_driver(struct serio_driver *drv);



static int serio_connect_driver(struct serio *serio, struct serio_driver *drv)
{
	int retval;

	mutex_lock(&serio->drv_mutex);
	retval = drv->connect(serio, drv);
	mutex_unlock(&serio->drv_mutex);

	return retval;
}

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Linus Torvalds
45
91.84%
1
50.00%
Arjan van de Ven
4
8.16%
1
50.00%
Total
49
100.00%
2
100.00%



static int serio_reconnect_driver(struct serio *serio)
{
	int retval = -1;

	mutex_lock(&serio->drv_mutex);
	if (serio->drv && serio->drv->reconnect)
		retval = serio->drv->reconnect(serio);
	mutex_unlock(&serio->drv_mutex);

	return retval;
}

Contributors
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Linus Torvalds
55
93.22%
1
50.00%
Arjan van de Ven
4
6.78%
1
50.00%
Total
59
100.00%
2
100.00%



static void serio_disconnect_driver(struct serio *serio)
{
	mutex_lock(&serio->drv_mutex);
	if (serio->drv)
		serio->drv->disconnect(serio);
	mutex_unlock(&serio->drv_mutex);
}

Contributors
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Linus Torvalds
38
90.48%
1
50.00%
Arjan van de Ven
4
9.52%
1
50.00%
Total
42
100.00%
2
100.00%



static int serio_match_port(const struct serio_device_id *ids, struct serio *serio)
{
	while (ids->type || ids->proto) {
		if ((ids->type == SERIO_ANY || ids->type == serio->id.type) &&
		    (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) &&
		    (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) &&
		    (ids->id == SERIO_ANY || ids->id == serio->id.id))
			return 1;
		ids++;
	}
	return 0;
}

Contributors
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Dmitry Torokhov
112
100.00%
1
100.00%
Total
112
100.00%
1
100.00%

/*
 * Basic serio -> driver core mappings
 */



static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
{
	int error;

	if (serio_match_port(drv->id_table, serio)) {

		serio->dev.driver = &drv->driver;
		if (serio_connect_driver(serio, drv)) {
			serio->dev.driver = NULL;
			return -ENODEV;
		}

		error = device_bind_driver(&serio->dev);
		if (error) {
			dev_warn(&serio->dev,
				 "device_bind_driver() failed for %s (%s) and %s, error: %d\n",
				 serio->phys, serio->name,
				 drv->description, error);
			serio_disconnect_driver(serio);
			serio->dev.driver = NULL;
			return error;
		}
	}
	return 0;
}

Contributors
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Dmitry Torokhov
124
99.20%
8
88.89%
Linus Torvalds
1
0.80%
1
11.11%
Total
125
100.00%
9
100.00%



static void serio_find_driver(struct serio *serio)
{
	int error;

	error = device_attach(&serio->dev);
	if (error < 0 && error != -EPROBE_DEFER)
		dev_warn(&serio->dev,
			 "device_attach() failed for %s (%s), error: %d\n",
			 serio->phys, serio->name, error);
}


Contributors
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Randy Dunlap
24
43.64%
1
16.67%
Linus Torvalds (pre-git)
13
23.64%
1
16.67%
Dmitry Torokhov
13
23.64%
3
50.00%
Grygorii Strashko
5
9.09%
1
16.67%
Total
55
100.00%
6
100.00%

/*
 * Serio event processing.
 */


enum serio_event_type {
	
SERIO_RESCAN_PORT,
	
SERIO_RECONNECT_PORT,
	
SERIO_RECONNECT_SUBTREE,
	
SERIO_REGISTER_PORT,
	
SERIO_ATTACH_DRIVER,
};


struct serio_event {
	
enum serio_event_type type;
	
void *object;
	
struct module *owner;
	
struct list_head node;
};

static DEFINE_SPINLOCK(serio_event_lock);	/* protects serio_event_list */
static LIST_HEAD(serio_event_list);



static struct serio_event *serio_get_event(void)
{
	struct serio_event *event = NULL;
	unsigned long flags;

	spin_lock_irqsave(&serio_event_lock, flags);

	if (!list_empty(&serio_event_list)) {
		event = list_first_entry(&serio_event_list,
					 struct serio_event, node);
		list_del_init(&event->node);
	}

	spin_unlock_irqrestore(&serio_event_lock, flags);
	return event;
}

Contributors
Person
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CommitProp
Dmitry Torokhov
47
65.28%
5
45.45%
Vojtech Pavlik
21
29.17%
4
36.36%
Linus Torvalds
2
2.78%
1
9.09%
Adrian Bunk
2
2.78%
1
9.09%
Total
72
100.00%
11
100.00%



static void serio_free_event(struct serio_event *event)
{
	module_put(event->owner);
	kfree(event);
}

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Dmitry Torokhov
23
100.00%
1
100.00%
Total
23
100.00%
1
100.00%



static void serio_remove_duplicate_events(void *object,
					  enum serio_event_type type)
{
	struct serio_event *e, *next;
	unsigned long flags;

	spin_lock_irqsave(&serio_event_lock, flags);

	list_for_each_entry_safe(e, next, &serio_event_list, node) {
		if (object == e->object) {
			/*
                         * If this event is of different type we should not
                         * look further - we only suppress duplicate events
                         * that were sent back-to-back.
                         */
			if (type != e->type)
				break;

			list_del_init(&e->node);
			serio_free_event(e);
		}
	}

	spin_unlock_irqrestore(&serio_event_lock, flags);
}

Contributors
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CommitProp
Dmitry Torokhov
73
83.91%
5
62.50%
Vojtech Pavlik
8
9.20%
2
25.00%
Duncan Laurie
6
6.90%
1
12.50%
Total
87
100.00%
8
100.00%



static void serio_handle_event(struct work_struct *work)
{
	struct serio_event *event;

	mutex_lock(&serio_mutex);

	while ((event = serio_get_event())) {

		switch (event->type) {

		case SERIO_REGISTER_PORT:
			serio_add_port(event->object);
			break;

		case SERIO_RECONNECT_PORT:
			serio_reconnect_port(event->object);
			break;

		case SERIO_RESCAN_PORT:
			serio_disconnect_port(event->object);
			serio_find_driver(event->object);
			break;

		case SERIO_RECONNECT_SUBTREE:
			serio_reconnect_subtree(event->object);
			break;

		case SERIO_ATTACH_DRIVER:
			serio_attach_driver(event->object);
			break;
		}

		serio_remove_duplicate_events(event->object, event->type);
		serio_free_event(event);
	}

	mutex_unlock(&serio_mutex);
}

Contributors
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CommitProp
Dmitry Torokhov
90
72.00%
2
25.00%
Vojtech Pavlik
27
21.60%
4
50.00%
Duncan Laurie
6
4.80%
1
12.50%
Linus Torvalds (pre-git)
2
1.60%
1
12.50%
Total
125
100.00%
8
100.00%

static DECLARE_WORK(serio_event_work, serio_handle_event);



static int serio_queue_event(void *object, struct module *owner,
			     enum serio_event_type event_type)
{
	unsigned long flags;
	struct serio_event *event;
	int retval = 0;

	spin_lock_irqsave(&serio_event_lock, flags);

	/*
         * Scan event list for the other events for the same serio port,
         * starting with the most recent one. If event is the same we
         * do not need add new one. If event is of different type we
         * need to add this event and should not look further because
         * we need to preseve sequence of distinct events.
         */
	list_for_each_entry_reverse(event, &serio_event_list, node) {
		if (event->object == object) {
			if (event->type == event_type)
				goto out;
			break;
		}
	}

	event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC);
	if (!event) {
		pr_err("Not enough memory to queue event %d\n", event_type);
		retval = -ENOMEM;
		goto out;
	}

	if (!try_module_get(owner)) {
		pr_warning("Can't get module reference, dropping event %d\n",
			   event_type);
		kfree(event);
		retval = -EINVAL;
		goto out;
	}

	event->type = event_type;
	event->object = object;
	event->owner = owner;

	list_add_tail(&event->node, &serio_event_list);
	queue_work(system_long_wq, &serio_event_work);

out:
	spin_unlock_irqrestore(&serio_event_lock, flags);
	return retval;
}

Contributors
Person
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CommitProp
Dmitry Torokhov
160
84.66%
9
60.00%
Vojtech Pavlik
21
11.11%
4
26.67%
Linus Torvalds (pre-git)
4
2.12%
1
6.67%
David Shaohua Li
4
2.12%
1
6.67%
Total
189
100.00%
15
100.00%

/*
 * Remove all events that have been submitted for a given
 * object, be it serio port or driver.
 */


static void serio_remove_pending_events(void *object)
{
	struct serio_event *event, *next;
	unsigned long flags;

	spin_lock_irqsave(&serio_event_lock, flags);

	list_for_each_entry_safe(event, next, &serio_event_list, node) {
		if (event->object == object) {
			list_del_init(&event->node);
			serio_free_event(event);
		}
	}

	spin_unlock_irqrestore(&serio_event_lock, flags);
}

Contributors
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Vojtech Pavlik
45
61.64%
2
33.33%
Dmitry Torokhov
28
38.36%
4
66.67%
Total
73
100.00%
6
100.00%

/*
 * Locate child serio port (if any) that has not been fully registered yet.
 *
 * Children are registered by driver's connect() handler so there can't be a
 * grandchild pending registration together with a child.
 */


static struct serio *serio_get_pending_child(struct serio *parent)
{
	struct serio_event *event;
	struct serio *serio, *child = NULL;
	unsigned long flags;

	spin_lock_irqsave(&serio_event_lock, flags);

	list_for_each_entry(event, &serio_event_list, node) {
		if (event->type == SERIO_REGISTER_PORT) {
			serio = event->object;
			if (serio->parent == parent) {
				child = serio;
				break;
			}
		}
	}

	spin_unlock_irqrestore(&serio_event_lock, flags);
	return child;
}

Contributors
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Dmitry Torokhov
78
84.78%
2
66.67%
Vojtech Pavlik
14
15.22%
1
33.33%
Total
92
100.00%
3
100.00%

/*
 * Serio port operations
 */



static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%s\n", serio->name);
}

Contributors
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Dmitry Torokhov
37
88.10%
1
50.00%
Yani Ioannou
5
11.90%
1
50.00%
Total
42
100.00%
2
100.00%



static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);

	return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n",
			serio->id.type, serio->id.proto, serio->id.id, serio->id.extra);
}

Contributors
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Dmitry Torokhov
61
98.39%
1
50.00%
Greg Kroah-Hartman
1
1.61%
1
50.00%
Total
62
100.00%
2
100.00%



static ssize_t type_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%02x\n", serio->id.type);
}

Contributors
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Tokens
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CommitProp
Dmitry Torokhov
38
86.36%
1
33.33%
Yani Ioannou
5
11.36%
1
33.33%
Greg Kroah-Hartman
1
2.27%
1
33.33%
Total
44
100.00%
3
100.00%



static ssize_t proto_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%02x\n", serio->id.proto);
}

Contributors
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Tokens
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CommitProp
Dmitry Torokhov
38
86.36%
1
33.33%
Yani Ioannou
5
11.36%
1
33.33%
Greg Kroah-Hartman
1
2.27%
1
33.33%
Total
44
100.00%
3
100.00%



static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%02x\n", serio->id.id);
}

Contributors
Person
Tokens
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CommitProp
Dmitry Torokhov
38
86.36%
1
33.33%
Yani Ioannou
5
11.36%
1
33.33%
Greg Kroah-Hartman
1
2.27%
1
33.33%
Total
44
100.00%
3
100.00%



static ssize_t extra_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%02x\n", serio->id.extra);
}

Contributors
Person
Tokens
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CommitProp
Dmitry Torokhov
38
86.36%
1
33.33%
Yani Ioannou
5
11.36%
1
33.33%
Greg Kroah-Hartman
1
2.27%
1
33.33%
Total
44
100.00%
3
100.00%



static ssize_t drvctl_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct serio *serio = to_serio_port(dev);
	struct device_driver *drv;
	int error;

	error = mutex_lock_interruptible(&serio_mutex);
	if (error)
		return error;

	if (!strncmp(buf, "none", count)) {
		serio_disconnect_port(serio);
	} else if (!strncmp(buf, "reconnect", count)) {
		serio_reconnect_subtree(serio);
	} else if (!strncmp(buf, "rescan", count)) {
		serio_disconnect_port(serio);
		serio_find_driver(serio);
		serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT);
	} else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
		serio_disconnect_port(serio);
		error = serio_bind_driver(serio, to_serio_driver(drv));
		serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT);
	} else {
		error = -EINVAL;
	}

	mutex_unlock(&serio_mutex);

	return error ? error : count;
}

Contributors
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CommitProp
Dmitry Torokhov
167
86.98%
4
44.44%
Duncan Laurie
14
7.29%
1
11.11%
Yani Ioannou
5
2.60%
1
11.11%
Arjan van de Ven
4
2.08%
1
11.11%
Dmitry Baryshkov
1
0.52%
1
11.11%
Greg Kroah-Hartman
1
0.52%
1
11.11%
Total
192
100.00%
9
100.00%



static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);
	return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto");
}

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Dmitry Torokhov
41
89.13%
1
50.00%
Yani Ioannou
5
10.87%
1
50.00%
Total
46
100.00%
2
100.00%



static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	struct serio *serio = to_serio_port(dev);
	int retval;

	retval = count;
	if (!strncmp(buf, "manual", count)) {
		serio->manual_bind = true;
	} else if (!strncmp(buf, "auto", count)) {
		serio->manual_bind = false;
	} else {
		retval = -EINVAL;
	}

	return retval;
}

Contributors
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Dmitry Torokhov
88
94.62%
2
66.67%
Yani Ioannou
5
5.38%
1
33.33%
Total
93
100.00%
3
100.00%



static ssize_t firmware_id_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct serio *serio = to_serio_port(dev);

	return sprintf(buf, "%s\n", serio->firmware_id);
}

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Hans de Goede
42
100.00%
1
100.00%
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42
100.00%
1
100.00%

static DEVICE_ATTR_RO(type);
static DEVICE_ATTR_RO(proto);
static DEVICE_ATTR_RO(id);
static DEVICE_ATTR_RO(extra);


static struct attribute *serio_device_id_attrs[] = {
	&dev_attr_type.attr,
	&dev_attr_proto.attr,
	&dev_attr_id.attr,
	&dev_attr_extra.attr,
	NULL
};


static struct attribute_group serio_id_attr_group = {
	.name	= "id",
	.attrs	= serio_device_id_attrs,
};

static DEVICE_ATTR_RO(modalias);
static DEVICE_ATTR_WO(drvctl);
static DEVICE_ATTR(description, S_IRUGO, serio_show_description, NULL);
static DEVICE_ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode);
static DEVICE_ATTR_RO(firmware_id);


static struct attribute *serio_device_attrs[] = {
	&dev_attr_modalias.attr,
	&dev_attr_description.attr,
	&dev_attr_drvctl.attr,
	&dev_attr_bind_mode.attr,
	&dev_attr_firmware_id.attr,
	NULL
};


static struct attribute_group serio_device_attr_group = {
	.attrs	= serio_device_attrs,
};


static const struct attribute_group *serio_device_attr_groups[] = {
	&serio_id_attr_group,
	&serio_device_attr_group,
	NULL
};



static void serio_release_port(struct device *dev)
{
	struct serio *serio = to_serio_port(dev);

	kfree(serio);
	module_put(THIS_MODULE);
}

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Dmitry Torokhov
31
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1
100.00%
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31
100.00%
1
100.00%

/*
 * Prepare serio port for registration.
 */


static void serio_init_port(struct serio *serio)
{
	static atomic_t serio_no = ATOMIC_INIT(-1);

	__module_get(THIS_MODULE);

	INIT_LIST_HEAD(&serio->node);
	INIT_LIST_HEAD(&serio->child_node);
	INIT_LIST_HEAD(&serio->children);
	spin_lock_init(&serio->lock);
	mutex_init(&serio->drv_mutex);
	device_initialize(&serio->dev);
	dev_set_name(&serio->dev, "serio%lu",
		     (unsigned long)atomic_inc_return(&serio_no));
	serio->dev.bus = &serio_bus;
	serio->dev.release = serio_release_port;
	serio->dev.groups = serio_device_attr_groups;
	if (serio->parent) {
		serio->dev.parent = &serio->parent->dev;
		serio->depth = serio->parent->depth + 1;
	} else
		serio->depth = 0;
	lockdep_set_subclass(&serio->lock, serio->depth);
}

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Dmitry Torokhov
103
60.23%
6
42.86%
Jiri Kosina
33
19.30%
1
7.14%
Dmitry Baryshkov
16
9.36%
1
7.14%
Randy Dunlap
8
4.68%
1
7.14%
Andrew Morton
3
1.75%
1
7.14%
Kay Sievers
2
1.17%
1
7.14%
Richard Leitner
2
1.17%
1
7.14%
Arjan van de Ven
2
1.17%
1
7.14%
Aniroop Mathur
2
1.17%
1
7.14%
Total
171
100.00%
14
100.00%

/*
 * Complete serio port registration.
 * Driver core will attempt to find appropriate driver for the port.
 */


static void serio_add_port(struct serio *serio)
{
	struct serio *parent = serio->parent;
	int error;

	if (parent) {
		serio_pause_rx(parent);
		list_add_tail(