[deliverable/linux.git] / drivers / base / component.c

/*
 * Componentized device handling.
 *
 * 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.
 *
 * This is work in progress.  We gather up the component devices into a list,
 * and bind them when instructed.  At the moment, we're specific to the DRM
 * subsystem, and only handles one master device, but this doesn't have to be
 * the case.
 */
#include <linux/component.h>
#include <linux/device.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>

struct component;

struct component_match_array {
	void *data;
	int (*compare)(struct device *, void *);
	void (*release)(struct device *, void *);
	struct component *component;
	bool duplicate;
};

struct component_match {
	size_t alloc;
	size_t num;
	struct component_match_array *compare;
};

struct master {
	struct list_head node;
	bool bound;

	const struct component_master_ops *ops;
	struct device *dev;
	struct component_match *match;
};

struct component {
	struct list_head node;
	struct master *master;
	bool bound;

	const struct component_ops *ops;
	struct device *dev;
};

static DEFINE_MUTEX(component_mutex);
static LIST_HEAD(component_list);
static LIST_HEAD(masters);

static struct master *__master_find(struct device *dev,
	const struct component_master_ops *ops)
{
	struct master *m;

	list_for_each_entry(m, &masters, node)
		if (m->dev == dev && (!ops || m->ops == ops))
			return m;

	return NULL;
}

static struct component *find_component(struct master *master,
	int (*compare)(struct device *, void *), void *compare_data)
{
	struct component *c;

	list_for_each_entry(c, &component_list, node) {
		if (c->master && c->master != master)
			continue;

		if (compare(c->dev, compare_data))
			return c;
	}

	return NULL;
}

static int find_components(struct master *master)
{
	struct component_match *match = master->match;
	size_t i;
	int ret = 0;

	/*
	 * Scan the array of match functions and attach
	 * any components which are found to this master.
	 */
	for (i = 0; i < match->num; i++) {
		struct component_match_array *mc = &match->compare[i];
		struct component *c;

		dev_dbg(master->dev, "Looking for component %zu\n", i);

		if (match->compare[i].component)
			continue;

		c = find_component(master, mc->compare, mc->data);
		if (!c) {
			ret = -ENXIO;
			break;
		}

		dev_dbg(master->dev, "found component %s, duplicate %u\n", dev_name(c->dev), !!c->master);

		/* Attach this component to the master */
		match->compare[i].duplicate = !!c->master;
		match->compare[i].component = c;
		c->master = master;
	}
	return ret;
}

/* Detach component from associated master */
static void remove_component(struct master *master, struct component *c)
{
	size_t i;

	/* Detach the component from this master. */
	for (i = 0; i < master->match->num; i++)
		if (master->match->compare[i].component == c)
			master->match->compare[i].component = NULL;
}

/*
 * Try to bring up a master.  If component is NULL, we're interested in
 * this master, otherwise it's a component which must be present to try
 * and bring up the master.
 *
 * Returns 1 for successful bringup, 0 if not ready, or -ve errno.
 */
static int try_to_bring_up_master(struct master *master,
	struct component *component)
{
	int ret;

	dev_dbg(master->dev, "trying to bring up master\n");

	if (find_components(master)) {
		dev_dbg(master->dev, "master has incomplete components\n");
		return 0;
	}

	if (component && component->master != master) {
		dev_dbg(master->dev, "master is not for this component (%s)\n",
			dev_name(component->dev));
		return 0;
	}

	if (!devres_open_group(master->dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	/* Found all components */
	ret = master->ops->bind(master->dev);
	if (ret < 0) {
		devres_release_group(master->dev, NULL);
		dev_info(master->dev, "master bind failed: %d\n", ret);
		return ret;
	}

	master->bound = true;
	return 1;
}

static int try_to_bring_up_masters(struct component *component)
{
	struct master *m;
	int ret = 0;

	list_for_each_entry(m, &masters, node) {
		if (!m->bound) {
			ret = try_to_bring_up_master(m, component);
			if (ret != 0)
				break;
		}
	}

	return ret;
}

static void take_down_master(struct master *master)
{
	if (master->bound) {
		master->ops->unbind(master->dev);
		devres_release_group(master->dev, NULL);
		master->bound = false;
	}
}

static void component_match_release(struct device *master,
	struct component_match *match)
{
	unsigned int i;

	for (i = 0; i < match->num; i++) {
		struct component_match_array *mc = &match->compare[i];

		if (mc->release)
			mc->release(master, mc->data);
	}
}

static void devm_component_match_release(struct device *dev, void *res)
{
	component_match_release(dev, res);
}

static int component_match_realloc(struct device *dev,
	struct component_match *match, size_t num)
{
	struct component_match_array *new;

	if (match->alloc == num)
		return 0;

	new = devm_kmalloc_array(dev, num, sizeof(*new), GFP_KERNEL);
	if (!new)
		return -ENOMEM;

	if (match->compare) {
		memcpy(new, match->compare, sizeof(*new) *
					    min(match->num, num));
		devm_kfree(dev, match->compare);
	}
	match->compare = new;
	match->alloc = num;

	return 0;
}

/*
 * Add a component to be matched, with a release function.
 *
 * The match array is first created or extended if necessary.
 */
void component_match_add_release(struct device *master,
	struct component_match **matchptr,
	void (*release)(struct device *, void *),
	int (*compare)(struct device *, void *), void *compare_data)
{
	struct component_match *match = *matchptr;

	if (IS_ERR(match))
		return;

	if (!match) {
		match = devres_alloc(devm_component_match_release,
				     sizeof(*match), GFP_KERNEL);
		if (!match) {
			*matchptr = ERR_PTR(-ENOMEM);
			return;
		}

		devres_add(master, match);

		*matchptr = match;
	}

	if (match->num == match->alloc) {
		size_t new_size = match ? match->alloc + 16 : 15;
		int ret;

		ret = component_match_realloc(master, match, new_size);
		if (ret) {
			*matchptr = ERR_PTR(ret);
			return;
		}
	}

	match->compare[match->num].compare = compare;
	match->compare[match->num].release = release;
	match->compare[match->num].data = compare_data;
	match->compare[match->num].component = NULL;
	match->num++;
}
EXPORT_SYMBOL(component_match_add_release);

int component_master_add_with_match(struct device *dev,
	const struct component_master_ops *ops,
	struct component_match *match)
{
	struct master *master;
	int ret;

	/* Reallocate the match array for its true size */
	ret = component_match_realloc(dev, match, match->num);
	if (ret)
		return ret;

	master = kzalloc(sizeof(*master), GFP_KERNEL);
	if (!master)
		return -ENOMEM;

	master->dev = dev;
	master->ops = ops;
	master->match = match;

	/* Add to the list of available masters. */
	mutex_lock(&component_mutex);
	list_add(&master->node, &masters);

	ret = try_to_bring_up_master(master, NULL);

	if (ret < 0) {
		/* Delete off the list if we weren't successful */
		list_del(&master->node);
		kfree(master);
	}
	mutex_unlock(&component_mutex);

	return ret < 0 ? ret : 0;
}
EXPORT_SYMBOL_GPL(component_master_add_with_match);

void component_master_del(struct device *dev,
	const struct component_master_ops *ops)
{
	struct master *master;
	int i;

	mutex_lock(&component_mutex);
	master = __master_find(dev, ops);
	if (master) {
		struct component_match *match = master->match;

		take_down_master(master);

		list_del(&master->node);

		if (match) {
			for (i = 0; i < match->num; i++) {
				struct component *c = match->compare[i].component;
				if (c)
					c->master = NULL;
			}
		}
		kfree(master);
	}
	mutex_unlock(&component_mutex);
}
EXPORT_SYMBOL_GPL(component_master_del);

static void component_unbind(struct component *component,
	struct master *master, void *data)
{
	WARN_ON(!component->bound);

	component->ops->unbind(component->dev, master->dev, data);
	component->bound = false;

	/* Release all resources claimed in the binding of this component */
	devres_release_group(component->dev, component);
}

void component_unbind_all(struct device *master_dev, void *data)
{
	struct master *master;
	struct component *c;
	size_t i;

	WARN_ON(!mutex_is_locked(&component_mutex));

	master = __master_find(master_dev, NULL);
	if (!master)
		return;

	/* Unbind components in reverse order */
	for (i = master->match->num; i--; )
		if (!master->match->compare[i].duplicate) {
			c = master->match->compare[i].component;
			component_unbind(c, master, data);
		}
}
EXPORT_SYMBOL_GPL(component_unbind_all);

static int component_bind(struct component *component, struct master *master,
	void *data)
{
	int ret;

	/*
	 * Each component initialises inside its own devres group.
	 * This allows us to roll-back a failed component without
	 * affecting anything else.
	 */
	if (!devres_open_group(master->dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	/*
	 * Also open a group for the device itself: this allows us
	 * to release the resources claimed against the sub-device
	 * at the appropriate moment.
	 */
	if (!devres_open_group(component->dev, component, GFP_KERNEL)) {
		devres_release_group(master->dev, NULL);
		return -ENOMEM;
	}

	dev_dbg(master->dev, "binding %s (ops %ps)\n",
		dev_name(component->dev), component->ops);

	ret = component->ops->bind(component->dev, master->dev, data);
	if (!ret) {
		component->bound = true;

		/*
		 * Close the component device's group so that resources
		 * allocated in the binding are encapsulated for removal
		 * at unbind.  Remove the group on the DRM device as we
		 * can clean those resources up independently.
		 */
		devres_close_group(component->dev, NULL);
		devres_remove_group(master->dev, NULL);

		dev_info(master->dev, "bound %s (ops %ps)\n",
			 dev_name(component->dev), component->ops);
	} else {
		devres_release_group(component->dev, NULL);
		devres_release_group(master->dev, NULL);

		dev_err(master->dev, "failed to bind %s (ops %ps): %d\n",
			dev_name(component->dev), component->ops, ret);
	}

	return ret;
}

int component_bind_all(struct device *master_dev, void *data)
{
	struct master *master;
	struct component *c;
	size_t i;
	int ret = 0;

	WARN_ON(!mutex_is_locked(&component_mutex));

	master = __master_find(master_dev, NULL);
	if (!master)
		return -EINVAL;

	/* Bind components in match order */
	for (i = 0; i < master->match->num; i++)
		if (!master->match->compare[i].duplicate) {
			c = master->match->compare[i].component;
			ret = component_bind(c, master, data);
			if (ret)
				break;
		}

	if (ret != 0) {
		for (; i--; )
			if (!master->match->compare[i].duplicate) {
				c = master->match->compare[i].component;
				component_unbind(c, master, data);
			}
	}

	return ret;
}
EXPORT_SYMBOL_GPL(component_bind_all);

int component_add(struct device *dev, const struct component_ops *ops)
{
	struct component *component;
	int ret;

	component = kzalloc(sizeof(*component), GFP_KERNEL);
	if (!component)
		return -ENOMEM;

	component->ops = ops;
	component->dev = dev;

	dev_dbg(dev, "adding component (ops %ps)\n", ops);

	mutex_lock(&component_mutex);
	list_add_tail(&component->node, &component_list);

	ret = try_to_bring_up_masters(component);
	if (ret < 0) {
		list_del(&component->node);

		kfree(component);
	}
	mutex_unlock(&component_mutex);

	return ret < 0 ? ret : 0;
}
EXPORT_SYMBOL_GPL(component_add);

void component_del(struct device *dev, const struct component_ops *ops)
{
	struct component *c, *component = NULL;

	mutex_lock(&component_mutex);
	list_for_each_entry(c, &component_list, node)
		if (c->dev == dev && c->ops == ops) {
			list_del(&c->node);
			component = c;
			break;
		}

	if (component && component->master) {
		take_down_master(component->master);
		remove_component(component->master, component);
	}

	mutex_unlock(&component_mutex);

	WARN_ON(!component);
	kfree(component);
}
EXPORT_SYMBOL_GPL(component_del);

MODULE_LICENSE("GPL v2");
Commit	Line	Data
2a41e607 RK	1	/*
	2	* Componentized device handling.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* This is work in progress. We gather up the component devices into a list,
	9	* and bind them when instructed. At the moment, we're specific to the DRM
	10	* subsystem, and only handles one master device, but this doesn't have to be
	11	* the case.
	12	*/
	13	#include <linux/component.h>
	14	#include <linux/device.h>
	15	#include <linux/kref.h>
	16	#include <linux/list.h>
	17	#include <linux/module.h>
	18	#include <linux/mutex.h>
	19	#include <linux/slab.h>
	20
ffc30b74 RK	21	struct component;
ffc30b74 RK	22
ce657b1c RK	23	struct component_match_array {
	24	void *data;
	25	int (compare)(struct device , void *);
	26	void (release)(struct device , void *);
	27	struct component *component;
	28	bool duplicate;
	29	};
	30
6955b582 RK	31	struct component_match {
	32	size_t alloc;
	33	size_t num;
ce657b1c	34	struct component_match_array *compare;
6955b582 RK	35	};
6955b582 RK	36
2a41e607 RK	37	struct master {
2a41e607 RK	38	struct list_head node;
2a41e607 RK	39	bool bound;
	40
	41	const struct component_master_ops *ops;
	42	struct device *dev;
6955b582	43	struct component_match *match;
2a41e607 RK	44	};
	45
	46	struct component {
	47	struct list_head node;
2a41e607 RK	48	struct master *master;
	49	bool bound;
	50
	51	const struct component_ops *ops;
	52	struct device *dev;
	53	};
	54
	55	static DEFINE_MUTEX(component_mutex);
	56	static LIST_HEAD(component_list);
	57	static LIST_HEAD(masters);
	58
	59	static struct master __master_find(struct device dev,
	60	const struct component_master_ops *ops)
	61	{
	62	struct master *m;
	63
	64	list_for_each_entry(m, &masters, node)
	65	if (m->dev == dev && (!ops \|\| m->ops == ops))
	66	return m;
	67
	68	return NULL;
	69	}
	70
ffc30b74	71	static struct component find_component(struct master master,
2a41e607 RK	72	int (compare)(struct device , void ), void compare_data)
	73	{
	74	struct component *c;
2a41e607 RK	75
2a41e607 RK	76	list_for_each_entry(c, &component_list, node) {
fcbcebce	77	if (c->master && c->master != master)
2a41e607 RK	78	continue;
2a41e607 RK	79
ffc30b74 RK	80	if (compare(c->dev, compare_data))
ffc30b74 RK	81	return c;
2a41e607 RK	82	}
2a41e607 RK	83
ffc30b74	84	return NULL;
2a41e607	85	}
2a41e607	86
6955b582 RK	87	static int find_components(struct master *master)
	88	{
	89	struct component_match *match = master->match;
	90	size_t i;
	91	int ret = 0;
	92
6955b582 RK	93	/*
	94	* Scan the array of match functions and attach
	95	* any components which are found to this master.
	96	*/
	97	for (i = 0; i < match->num; i++) {
ce657b1c	98	struct component_match_array *mc = &match->compare[i];
ffc30b74 RK	99	struct component *c;
	100
	101	dev_dbg(master->dev, "Looking for component %zu\n", i);
	102
	103	if (match->compare[i].component)
	104	continue;
	105
ce657b1c	106	c = find_component(master, mc->compare, mc->data);
ffc30b74 RK	107	if (!c) {
ffc30b74 RK	108	ret = -ENXIO;
6955b582	109	break;
ffc30b74 RK	110	}
	111
	112	dev_dbg(master->dev, "found component %s, duplicate %u\n", dev_name(c->dev), !!c->master);
	113
	114	/* Attach this component to the master */
	115	match->compare[i].duplicate = !!c->master;
	116	match->compare[i].component = c;
	117	c->master = master;
6955b582 RK	118	}
	119	return ret;
	120	}
	121
ffc30b74 RK	122	/* Detach component from associated master */
ffc30b74 RK	123	static void remove_component(struct master master, struct component c)
2a41e607	124	{
ffc30b74	125	size_t i;
2a41e607	126
ffc30b74 RK	127	/* Detach the component from this master. */
	128	for (i = 0; i < master->match->num; i++)
	129	if (master->match->compare[i].component == c)
	130	master->match->compare[i].component = NULL;
2a41e607 RK	131	}
	132
	133	/*
	134	* Try to bring up a master. If component is NULL, we're interested in
	135	* this master, otherwise it's a component which must be present to try
	136	* and bring up the master.
	137	*
	138	* Returns 1 for successful bringup, 0 if not ready, or -ve errno.
	139	*/
	140	static int try_to_bring_up_master(struct master *master,
	141	struct component *component)
	142	{
c334940e RK	143	int ret;
c334940e RK	144
ffc30b74 RK	145	dev_dbg(master->dev, "trying to bring up master\n");
ffc30b74 RK	146
6955b582	147	if (find_components(master)) {
ffc30b74 RK	148	dev_dbg(master->dev, "master has incomplete components\n");
ffc30b74 RK	149	return 0;
c334940e	150	}
2a41e607	151
c334940e	152	if (component && component->master != master) {
ffc30b74 RK	153	dev_dbg(master->dev, "master is not for this component (%s)\n",
	154	dev_name(component->dev));
	155	return 0;
c334940e	156	}
2a41e607	157
ffc30b74 RK	158	if (!devres_open_group(master->dev, NULL, GFP_KERNEL))
ffc30b74 RK	159	return -ENOMEM;
2a41e607	160
c334940e RK	161	/* Found all components */
	162	ret = master->ops->bind(master->dev);
	163	if (ret < 0) {
	164	devres_release_group(master->dev, NULL);
	165	dev_info(master->dev, "master bind failed: %d\n", ret);
ffc30b74	166	return ret;
c334940e	167	}
9e1ccb4a	168
c334940e RK	169	master->bound = true;
c334940e RK	170	return 1;
2a41e607 RK	171	}
	172
	173	static int try_to_bring_up_masters(struct component *component)
	174	{
	175	struct master *m;
	176	int ret = 0;
	177
	178	list_for_each_entry(m, &masters, node) {
29f1c7fd RK	179	if (!m->bound) {
	180	ret = try_to_bring_up_master(m, component);
	181	if (ret != 0)
	182	break;
	183	}
2a41e607 RK	184	}
	185
	186	return ret;
	187	}
	188
	189	static void take_down_master(struct master *master)
	190	{
	191	if (master->bound) {
	192	master->ops->unbind(master->dev);
9e1ccb4a	193	devres_release_group(master->dev, NULL);
2a41e607 RK	194	master->bound = false;
2a41e607 RK	195	}
2a41e607 RK	196	}
2a41e607 RK	197
ce657b1c RK	198	static void component_match_release(struct device *master,
ce657b1c RK	199	struct component_match *match)
6955b582	200	{
ce657b1c RK	201	unsigned int i;
	202
	203	for (i = 0; i < match->num; i++) {
	204	struct component_match_array *mc = &match->compare[i];
	205
	206	if (mc->release)
	207	mc->release(master, mc->data);
	208	}
6955b582 RK	209	}
6955b582 RK	210
ce657b1c RK	211	static void devm_component_match_release(struct device dev, void res)
	212	{
	213	component_match_release(dev, res);
	214	}
	215
	216	static int component_match_realloc(struct device *dev,
6955b582 RK	217	struct component_match *match, size_t num)
6955b582 RK	218	{
ce657b1c	219	struct component_match_array *new;
6955b582	220
ce657b1c RK	221	if (match->alloc == num)
ce657b1c RK	222	return 0;
6955b582	223
ce657b1c	224	new = devm_kmalloc_array(dev, num, sizeof(*new), GFP_KERNEL);
6955b582	225	if (!new)
ce657b1c	226	return -ENOMEM;
6955b582	227
ce657b1c RK	228	if (match->compare) {
	229	memcpy(new, match->compare, sizeof(new)
	230	min(match->num, num));
	231	devm_kfree(dev, match->compare);
6955b582	232	}
ce657b1c RK	233	match->compare = new;
ce657b1c RK	234	match->alloc = num;
6955b582	235
ce657b1c	236	return 0;
6955b582 RK	237	}
	238
	239	/*
ce657b1c	240	* Add a component to be matched, with a release function.
6955b582 RK	241	*
	242	* The match array is first created or extended if necessary.
	243	*/
ce657b1c RK	244	void component_match_add_release(struct device *master,
	245	struct component_match **matchptr,
	246	void (release)(struct device , void *),
6955b582 RK	247	int (compare)(struct device , void ), void compare_data)
	248	{
	249	struct component_match match = matchptr;
	250
	251	if (IS_ERR(match))
	252	return;
	253
ce657b1c RK	254	if (!match) {
	255	match = devres_alloc(devm_component_match_release,
	256	sizeof(*match), GFP_KERNEL);
	257	if (!match) {
	258	*matchptr = ERR_PTR(-ENOMEM);
	259	return;
	260	}
6955b582	261
ce657b1c	262	devres_add(master, match);
6955b582 RK	263
6955b582 RK	264	*matchptr = match;
ce657b1c	265	}
6955b582	266
ce657b1c RK	267	if (match->num == match->alloc) {
	268	size_t new_size = match ? match->alloc + 16 : 15;
	269	int ret;
	270
	271	ret = component_match_realloc(master, match, new_size);
	272	if (ret) {
	273	*matchptr = ERR_PTR(ret);
6955b582	274	return;
ce657b1c	275	}
6955b582 RK	276	}
6955b582 RK	277
ce657b1c RK	278	match->compare[match->num].compare = compare;
ce657b1c RK	279	match->compare[match->num].release = release;
6955b582	280	match->compare[match->num].data = compare_data;
ffc30b74	281	match->compare[match->num].component = NULL;
6955b582 RK	282	match->num++;
6955b582 RK	283	}
ce657b1c	284	EXPORT_SYMBOL(component_match_add_release);
6955b582 RK	285
	286	int component_master_add_with_match(struct device *dev,
	287	const struct component_master_ops *ops,
	288	struct component_match *match)
2a41e607 RK	289	{
	290	struct master *master;
	291	int ret;
	292
fae9e2e0	293	/* Reallocate the match array for its true size */
ce657b1c RK	294	ret = component_match_realloc(dev, match, match->num);
	295	if (ret)
	296	return ret;
6955b582	297
2a41e607 RK	298	master = kzalloc(sizeof(*master), GFP_KERNEL);
	299	if (!master)
	300	return -ENOMEM;
	301
	302	master->dev = dev;
	303	master->ops = ops;
6955b582	304	master->match = match;
2a41e607 RK	305
	306	/* Add to the list of available masters. */
	307	mutex_lock(&component_mutex);
	308	list_add(&master->node, &masters);
	309
	310	ret = try_to_bring_up_master(master, NULL);
	311
	312	if (ret < 0) {
	313	/* Delete off the list if we weren't successful */
	314	list_del(&master->node);
	315	kfree(master);
	316	}
	317	mutex_unlock(&component_mutex);
	318
	319	return ret < 0 ? ret : 0;
	320	}
6955b582 RK	321	EXPORT_SYMBOL_GPL(component_master_add_with_match);
6955b582 RK	322
2a41e607 RK	323	void component_master_del(struct device *dev,
	324	const struct component_master_ops *ops)
	325	{
	326	struct master *master;
ffc30b74	327	int i;
2a41e607 RK	328
	329	mutex_lock(&component_mutex);
	330	master = __master_find(dev, ops);
	331	if (master) {
ffc30b74 RK	332	struct component_match *match = master->match;
ffc30b74 RK	333
2a41e607 RK	334	take_down_master(master);
	335
	336	list_del(&master->node);
ffc30b74 RK	337
	338	if (match) {
	339	for (i = 0; i < match->num; i++) {
	340	struct component *c = match->compare[i].component;
	341	if (c)
	342	c->master = NULL;
	343	}
	344	}
2a41e607 RK	345	kfree(master);
	346	}
	347	mutex_unlock(&component_mutex);
	348	}
	349	EXPORT_SYMBOL_GPL(component_master_del);
	350
	351	static void component_unbind(struct component *component,
	352	struct master master, void data)
	353	{
	354	WARN_ON(!component->bound);
	355
	356	component->ops->unbind(component->dev, master->dev, data);
	357	component->bound = false;
	358
	359	/* Release all resources claimed in the binding of this component */
	360	devres_release_group(component->dev, component);
	361	}
	362
	363	void component_unbind_all(struct device master_dev, void data)
	364	{
	365	struct master *master;
	366	struct component *c;
ffc30b74	367	size_t i;
2a41e607 RK	368
	369	WARN_ON(!mutex_is_locked(&component_mutex));
	370
	371	master = __master_find(master_dev, NULL);
	372	if (!master)
	373	return;
	374
ffc30b74 RK	375	/* Unbind components in reverse order */
	376	for (i = master->match->num; i--; )
	377	if (!master->match->compare[i].duplicate) {
	378	c = master->match->compare[i].component;
	379	component_unbind(c, master, data);
	380	}
2a41e607 RK	381	}
	382	EXPORT_SYMBOL_GPL(component_unbind_all);
	383
	384	static int component_bind(struct component component, struct master master,
	385	void *data)
	386	{
	387	int ret;
	388
	389	/*
	390	* Each component initialises inside its own devres group.
	391	* This allows us to roll-back a failed component without
	392	* affecting anything else.
	393	*/
	394	if (!devres_open_group(master->dev, NULL, GFP_KERNEL))
	395	return -ENOMEM;
	396
	397	/*
	398	* Also open a group for the device itself: this allows us
	399	* to release the resources claimed against the sub-device
	400	* at the appropriate moment.
	401	*/
	402	if (!devres_open_group(component->dev, component, GFP_KERNEL)) {
	403	devres_release_group(master->dev, NULL);
	404	return -ENOMEM;
	405	}
	406
	407	dev_dbg(master->dev, "binding %s (ops %ps)\n",
	408	dev_name(component->dev), component->ops);
	409
	410	ret = component->ops->bind(component->dev, master->dev, data);
	411	if (!ret) {
	412	component->bound = true;
	413
	414	/*
	415	* Close the component device's group so that resources
	416	* allocated in the binding are encapsulated for removal
	417	* at unbind. Remove the group on the DRM device as we
	418	* can clean those resources up independently.
	419	*/
	420	devres_close_group(component->dev, NULL);
	421	devres_remove_group(master->dev, NULL);
	422
	423	dev_info(master->dev, "bound %s (ops %ps)\n",
	424	dev_name(component->dev), component->ops);
	425	} else {
	426	devres_release_group(component->dev, NULL);
	427	devres_release_group(master->dev, NULL);
	428
	429	dev_err(master->dev, "failed to bind %s (ops %ps): %d\n",
	430	dev_name(component->dev), component->ops, ret);
	431	}
	432
	433	return ret;
	434	}
	435
	436	int component_bind_all(struct device master_dev, void data)
	437	{
	438	struct master *master;
	439	struct component *c;
ffc30b74	440	size_t i;
2a41e607 RK	441	int ret = 0;
	442
	443	WARN_ON(!mutex_is_locked(&component_mutex));
	444
	445	master = __master_find(master_dev, NULL);
	446	if (!master)
	447	return -EINVAL;
	448
ffc30b74 RK	449	/* Bind components in match order */
	450	for (i = 0; i < master->match->num; i++)
	451	if (!master->match->compare[i].duplicate) {
	452	c = master->match->compare[i].component;
	453	ret = component_bind(c, master, data);
	454	if (ret)
	455	break;
	456	}
2a41e607 RK	457
2a41e607 RK	458	if (ret != 0) {
ffc30b74 RK	459	for (; i--; )
	460	if (!master->match->compare[i].duplicate) {
	461	c = master->match->compare[i].component;
	462	component_unbind(c, master, data);
	463	}
2a41e607 RK	464	}
	465
	466	return ret;
	467	}
	468	EXPORT_SYMBOL_GPL(component_bind_all);
	469
	470	int component_add(struct device dev, const struct component_ops ops)
	471	{
	472	struct component *component;
	473	int ret;
	474
	475	component = kzalloc(sizeof(*component), GFP_KERNEL);
	476	if (!component)
	477	return -ENOMEM;
	478
	479	component->ops = ops;
	480	component->dev = dev;
	481
	482	dev_dbg(dev, "adding component (ops %ps)\n", ops);
	483
	484	mutex_lock(&component_mutex);
	485	list_add_tail(&component->node, &component_list);
	486
	487	ret = try_to_bring_up_masters(component);
	488	if (ret < 0) {
	489	list_del(&component->node);
	490
	491	kfree(component);
	492	}
	493	mutex_unlock(&component_mutex);
	494
	495	return ret < 0 ? ret : 0;
	496	}
	497	EXPORT_SYMBOL_GPL(component_add);
	498
	499	void component_del(struct device dev, const struct component_ops ops)
	500	{
	501	struct component c, component = NULL;
	502
	503	mutex_lock(&component_mutex);
	504	list_for_each_entry(c, &component_list, node)
	505	if (c->dev == dev && c->ops == ops) {
	506	list_del(&c->node);
	507	component = c;
	508	break;
	509	}
	510
ffc30b74	511	if (component && component->master) {
2a41e607	512	take_down_master(component->master);
ffc30b74 RK	513	remove_component(component->master, component);
ffc30b74 RK	514	}
2a41e607 RK	515
	516	mutex_unlock(&component_mutex);
	517
	518	WARN_ON(!component);
	519	kfree(component);
	520	}
	521	EXPORT_SYMBOL_GPL(component_del);
	522
	523	MODULE_LICENSE("GPL v2");