[linux.git] / drivers / i2c / i2c-core-of.c

/*
 * Linux I2C core OF support code
 *
 * Copyright (C) 2008 Jochen Friedrich <[email protected]>
 * based on a previous patch from Jon Smirl <[email protected]>
 *
 * Copyright (C) 2013, 2018 Wolfram Sang <[email protected]>
 *
 * 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.
 */

#include <dt-bindings/i2c/i2c.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include "i2c-core.h"

int of_i2c_get_board_info(struct device *dev, struct device_node *node,
			  struct i2c_board_info *info)
{
	u32 addr;
	int ret;

	memset(info, 0, sizeof(*info));

	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
		dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
		return -EINVAL;
	}

	ret = of_property_read_u32(node, "reg", &addr);
	if (ret) {
		dev_err(dev, "of_i2c: invalid reg on %pOF\n", node);
		return ret;
	}

	if (addr & I2C_TEN_BIT_ADDRESS) {
		addr &= ~I2C_TEN_BIT_ADDRESS;
		info->flags |= I2C_CLIENT_TEN;
	}

	if (addr & I2C_OWN_SLAVE_ADDRESS) {
		addr &= ~I2C_OWN_SLAVE_ADDRESS;
		info->flags |= I2C_CLIENT_SLAVE;
	}

	info->addr = addr;
	info->of_node = node;

	if (of_property_read_bool(node, "host-notify"))
		info->flags |= I2C_CLIENT_HOST_NOTIFY;

	if (of_get_property(node, "wakeup-source", NULL))
		info->flags |= I2C_CLIENT_WAKE;

	return 0;
}
EXPORT_SYMBOL_GPL(of_i2c_get_board_info);

static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
						 struct device_node *node)
{
	struct i2c_client *client;
	struct i2c_board_info info;
	int ret;

	dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);

	ret = of_i2c_get_board_info(&adap->dev, node, &info);
	if (ret)
		return ERR_PTR(ret);

	client = i2c_new_device(adap, &info);
	if (!client) {
		dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
		return ERR_PTR(-EINVAL);
	}
	return client;
}

void of_i2c_register_devices(struct i2c_adapter *adap)
{
	struct device_node *bus, *node;
	struct i2c_client *client;

	/* Only register child devices if the adapter has a node pointer set */
	if (!adap->dev.of_node)
		return;

	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");

	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
	if (!bus)
		bus = of_node_get(adap->dev.of_node);

	for_each_available_child_of_node(bus, node) {
		if (of_node_test_and_set_flag(node, OF_POPULATED))
			continue;

		client = of_i2c_register_device(adap, node);
		if (IS_ERR(client)) {
			dev_err(&adap->dev,
				 "Failed to create I2C device for %pOF\n",
				 node);
			of_node_clear_flag(node, OF_POPULATED);
		}
	}

	of_node_put(bus);
}

static int of_dev_node_match(struct device *dev, void *data)
{
	return dev->of_node == data;
}

/* must call put_device() when done with returned i2c_client device */
struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
{
	struct device *dev;
	struct i2c_client *client;

	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
	if (!dev)
		return NULL;

	client = i2c_verify_client(dev);
	if (!client)
		put_device(dev);

	return client;
}
EXPORT_SYMBOL(of_find_i2c_device_by_node);

/* must call put_device() when done with returned i2c_adapter device */
struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
{
	struct device *dev;
	struct i2c_adapter *adapter;

	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
	if (!dev)
		return NULL;

	adapter = i2c_verify_adapter(dev);
	if (!adapter)
		put_device(dev);

	return adapter;
}
EXPORT_SYMBOL(of_find_i2c_adapter_by_node);

/* must call i2c_put_adapter() when done with returned i2c_adapter device */
struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
{
	struct i2c_adapter *adapter;

	adapter = of_find_i2c_adapter_by_node(node);
	if (!adapter)
		return NULL;

	if (!try_module_get(adapter->owner)) {
		put_device(&adapter->dev);
		adapter = NULL;
	}

	return adapter;
}
EXPORT_SYMBOL(of_get_i2c_adapter_by_node);

static const struct of_device_id*
i2c_of_match_device_sysfs(const struct of_device_id *matches,
				  struct i2c_client *client)
{
	const char *name;

	for (; matches->compatible[0]; matches++) {
		/*
		 * Adding devices through the i2c sysfs interface provides us
		 * a string to match which may be compatible with the device
		 * tree compatible strings, however with no actual of_node the
		 * of_match_device() will not match
		 */
		if (sysfs_streq(client->name, matches->compatible))
			return matches;

		name = strchr(matches->compatible, ',');
		if (!name)
			name = matches->compatible;
		else
			name++;

		if (sysfs_streq(client->name, name))
			return matches;
	}

	return NULL;
}

const struct of_device_id
*i2c_of_match_device(const struct of_device_id *matches,
		     struct i2c_client *client)
{
	const struct of_device_id *match;

	if (!(client && matches))
		return NULL;

	match = of_match_device(matches, &client->dev);
	if (match)
		return match;

	return i2c_of_match_device_sysfs(matches, client);
}
EXPORT_SYMBOL_GPL(i2c_of_match_device);

#if IS_ENABLED(CONFIG_OF_DYNAMIC)
static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
			 void *arg)
{
	struct of_reconfig_data *rd = arg;
	struct i2c_adapter *adap;
	struct i2c_client *client;

	switch (of_reconfig_get_state_change(action, rd)) {
	case OF_RECONFIG_CHANGE_ADD:
		adap = of_find_i2c_adapter_by_node(rd->dn->parent);
		if (adap == NULL)
			return NOTIFY_OK;	/* not for us */

		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
			put_device(&adap->dev);
			return NOTIFY_OK;
		}

		client = of_i2c_register_device(adap, rd->dn);
		put_device(&adap->dev);

		if (IS_ERR(client)) {
			dev_err(&adap->dev, "failed to create client for '%pOF'\n",
				 rd->dn);
			of_node_clear_flag(rd->dn, OF_POPULATED);
			return notifier_from_errno(PTR_ERR(client));
		}
		break;
	case OF_RECONFIG_CHANGE_REMOVE:
		/* already depopulated? */
		if (!of_node_check_flag(rd->dn, OF_POPULATED))
			return NOTIFY_OK;

		/* find our device by node */
		client = of_find_i2c_device_by_node(rd->dn);
		if (client == NULL)
			return NOTIFY_OK;	/* no? not meant for us */

		/* unregister takes one ref away */
		i2c_unregister_device(client);

		/* and put the reference of the find */
		put_device(&client->dev);
		break;
	}

	return NOTIFY_OK;
}

struct notifier_block i2c_of_notifier = {
	.notifier_call = of_i2c_notify,
};
#endif /* CONFIG_OF_DYNAMIC */
Commit	Line	Data
5bf4fa7d WS	1	/*
	2	* Linux I2C core OF support code
	3	*
	4	* Copyright (C) 2008 Jochen Friedrich <[email protected]>
	5	* based on a previous patch from Jon Smirl <[email protected]>
	6	*
a1671af2	7	* Copyright (C) 2013, 2018 Wolfram Sang <[email protected]>
5bf4fa7d WS	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*/
	14
	15	#include <dt-bindings/i2c/i2c.h>
	16	#include <linux/device.h>
	17	#include <linux/err.h>
	18	#include <linux/i2c.h>
	19	#include <linux/module.h>
	20	#include <linux/of.h>
	21	#include <linux/of_device.h>
	22
	23	#include "i2c-core.h"
	24
da0086d0 BB	25	int of_i2c_get_board_info(struct device dev, struct device_node node,
da0086d0 BB	26	struct i2c_board_info *info)
5bf4fa7d	27	{
5bf4fa7d	28	u32 addr;
a1671af2	29	int ret;
5bf4fa7d	30
da0086d0	31	memset(info, 0, sizeof(*info));
5bf4fa7d	32
da0086d0 BB	33	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
	34	dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
	35	return -EINVAL;
5bf4fa7d WS	36	}
5bf4fa7d WS	37
a1671af2 WS	38	ret = of_property_read_u32(node, "reg", &addr);
a1671af2 WS	39	if (ret) {
da0086d0 BB	40	dev_err(dev, "of_i2c: invalid reg on %pOF\n", node);
da0086d0 BB	41	return ret;
5bf4fa7d WS	42	}
5bf4fa7d WS	43
5bf4fa7d WS	44	if (addr & I2C_TEN_BIT_ADDRESS) {
5bf4fa7d WS	45	addr &= ~I2C_TEN_BIT_ADDRESS;
da0086d0	46	info->flags \|= I2C_CLIENT_TEN;
5bf4fa7d WS	47	}
	48
	49	if (addr & I2C_OWN_SLAVE_ADDRESS) {
	50	addr &= ~I2C_OWN_SLAVE_ADDRESS;
da0086d0	51	info->flags \|= I2C_CLIENT_SLAVE;
5bf4fa7d WS	52	}
5bf4fa7d WS	53
da0086d0 BB	54	info->addr = addr;
da0086d0 BB	55	info->of_node = node;
5bf4fa7d WS	56
5bf4fa7d WS	57	if (of_property_read_bool(node, "host-notify"))
da0086d0	58	info->flags \|= I2C_CLIENT_HOST_NOTIFY;
5bf4fa7d WS	59
5bf4fa7d WS	60	if (of_get_property(node, "wakeup-source", NULL))
da0086d0 BB	61	info->flags \|= I2C_CLIENT_WAKE;
	62
	63	return 0;
	64	}
	65	EXPORT_SYMBOL_GPL(of_i2c_get_board_info);
	66
	67	static struct i2c_client of_i2c_register_device(struct i2c_adapter adap,
	68	struct device_node *node)
	69	{
	70	struct i2c_client *client;
	71	struct i2c_board_info info;
	72	int ret;
	73
	74	dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);
	75
	76	ret = of_i2c_get_board_info(&adap->dev, node, &info);
	77	if (ret)
	78	return ERR_PTR(ret);
5bf4fa7d	79
c49b0e07 WS	80	client = i2c_new_device(adap, &info);
c49b0e07 WS	81	if (!client) {
453a237c	82	dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
5bf4fa7d WS	83	return ERR_PTR(-EINVAL);
5bf4fa7d WS	84	}
c49b0e07	85	return client;
5bf4fa7d WS	86	}
	87
	88	void of_i2c_register_devices(struct i2c_adapter *adap)
	89	{
	90	struct device_node bus, node;
	91	struct i2c_client *client;
	92
	93	/* Only register child devices if the adapter has a node pointer set */
	94	if (!adap->dev.of_node)
	95	return;
	96
	97	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
	98
	99	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
	100	if (!bus)
	101	bus = of_node_get(adap->dev.of_node);
	102
	103	for_each_available_child_of_node(bus, node) {
	104	if (of_node_test_and_set_flag(node, OF_POPULATED))
	105	continue;
	106
	107	client = of_i2c_register_device(adap, node);
	108	if (IS_ERR(client)) {
f1c87ceb	109	dev_err(&adap->dev,
453a237c RH	110	"Failed to create I2C device for %pOF\n",
453a237c RH	111	node);
5bf4fa7d WS	112	of_node_clear_flag(node, OF_POPULATED);
	113	}
	114	}
	115
	116	of_node_put(bus);
	117	}
	118
	119	static int of_dev_node_match(struct device dev, void data)
	120	{
	121	return dev->of_node == data;
	122	}
	123
	124	/* must call put_device() when done with returned i2c_client device */
	125	struct i2c_client of_find_i2c_device_by_node(struct device_node node)
	126	{
	127	struct device *dev;
	128	struct i2c_client *client;
	129
	130	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
	131	if (!dev)
	132	return NULL;
	133
	134	client = i2c_verify_client(dev);
	135	if (!client)
	136	put_device(dev);
	137
	138	return client;
	139	}
	140	EXPORT_SYMBOL(of_find_i2c_device_by_node);
	141
	142	/* must call put_device() when done with returned i2c_adapter device */
	143	struct i2c_adapter of_find_i2c_adapter_by_node(struct device_node node)
	144	{
	145	struct device *dev;
	146	struct i2c_adapter *adapter;
	147
	148	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
	149	if (!dev)
	150	return NULL;
	151
	152	adapter = i2c_verify_adapter(dev);
	153	if (!adapter)
	154	put_device(dev);
	155
	156	return adapter;
	157	}
	158	EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
	159
	160	/* must call i2c_put_adapter() when done with returned i2c_adapter device */
	161	struct i2c_adapter of_get_i2c_adapter_by_node(struct device_node node)
	162	{
	163	struct i2c_adapter *adapter;
	164
	165	adapter = of_find_i2c_adapter_by_node(node);
	166	if (!adapter)
	167	return NULL;
	168
	169	if (!try_module_get(adapter->owner)) {
	170	put_device(&adapter->dev);
	171	adapter = NULL;
	172	}
	173
	174	return adapter;
	175	}
176	EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
177
178	static const struct of_device_id*
179	i2c_of_match_device_sysfs(const struct of_device_id *matches,
180	struct i2c_client *client)
181	{
182	const char *name;
183
184	for (; matches->compatible[0]; matches++) {
185	/*
186	* Adding devices through the i2c sysfs interface provides us
187	* a string to match which may be compatible with the device
188	* tree compatible strings, however with no actual of_node the
189	* of_match_device() will not match
190	*/
191	if (sysfs_streq(client->name, matches->compatible))
192	return matches;
193
194	name = strchr(matches->compatible, ',');
195	if (!name)
196	name = matches->compatible;
197	else
198	name++;
199
200	if (sysfs_streq(client->name, name))
201	return matches;
202	}
203
204	return NULL;
205	}
206
207	const struct of_device_id
208	i2c_of_match_device(const struct of_device_id matches,
209	struct i2c_client *client)
210	{
211	const struct of_device_id *match;
212
213	if (!(client && matches))
214	return NULL;
215
216	match = of_match_device(matches, &client->dev);
217	if (match)
218	return match;
219
220	return i2c_of_match_device_sysfs(matches, client);
221	}
222	EXPORT_SYMBOL_GPL(i2c_of_match_device);
223
224	#if IS_ENABLED(CONFIG_OF_DYNAMIC)
225	static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
226	void *arg)
227	{
228	struct of_reconfig_data *rd = arg;
229	struct i2c_adapter *adap;
230	struct i2c_client *client;
231
232	switch (of_reconfig_get_state_change(action, rd)) {
233	case OF_RECONFIG_CHANGE_ADD:
234	adap = of_find_i2c_adapter_by_node(rd->dn->parent);
235	if (adap == NULL)
236	return NOTIFY_OK; /* not for us */
237
238	if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
239	put_device(&adap->dev);
240	return NOTIFY_OK;
241	}
242
243	client = of_i2c_register_device(adap, rd->dn);
244	put_device(&adap->dev);
245
246	if (IS_ERR(client)) {
453a237c RH	247	dev_err(&adap->dev, "failed to create client for '%pOF'\n",
453a237c RH	248	rd->dn);
5bf4fa7d WS	249	of_node_clear_flag(rd->dn, OF_POPULATED);
	250	return notifier_from_errno(PTR_ERR(client));
	251	}
	252	break;
	253	case OF_RECONFIG_CHANGE_REMOVE:
	254	/* already depopulated? */
	255	if (!of_node_check_flag(rd->dn, OF_POPULATED))
	256	return NOTIFY_OK;
	257
	258	/* find our device by node */
	259	client = of_find_i2c_device_by_node(rd->dn);
	260	if (client == NULL)
	261	return NOTIFY_OK; /* no? not meant for us */
	262
	263	/* unregister takes one ref away */
	264	i2c_unregister_device(client);
	265
	266	/* and put the reference of the find */
	267	put_device(&client->dev);
	268	break;
	269	}
	270
	271	return NOTIFY_OK;
	272	}
	273
	274	struct notifier_block i2c_of_notifier = {
	275	.notifier_call = of_i2c_notify,
	276	};
	277	#endif /* CONFIG_OF_DYNAMIC */