[linux-2.6-block.git] / drivers / i2c / i2c-core-of.c

/*
 * Linux I2C core OF support code
 *
 * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
 * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
 *
 * Copyright (C) 2013 Wolfram Sang <wsa@the-dreams.de>
 *
 * 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"

static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
						 struct device_node *node)
{
	struct i2c_client *result;
	struct i2c_board_info info = {};
	struct dev_archdata dev_ad = {};
	const __be32 *addr_be;
	u32 addr;
	int len;

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

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

	addr_be = of_get_property(node, "reg", &len);
	if (!addr_be || (len < sizeof(*addr_be))) {
		dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
			node->full_name);
		return ERR_PTR(-EINVAL);
	}

	addr = be32_to_cpup(addr_be);
	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;
	}

	if (i2c_check_addr_validity(addr, info.flags)) {
		dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
			addr, node->full_name);
		return ERR_PTR(-EINVAL);
	}

	info.addr = addr;
	info.of_node = of_node_get(node);
	info.archdata = &dev_ad;

	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;

	result = i2c_new_device(adap, &info);
	if (result == NULL) {
		dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
			node->full_name);
		of_node_put(node);
		return ERR_PTR(-EINVAL);
	}
	return result;
}

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_warn(&adap->dev,
				 "Failed to create I2C device for %s\n",
				 node->full_name);
			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 '%s'\n",
				 rd->dn->full_name);
			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 <jochen@scram.de>
	5	* based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
	6	*
	7	* Copyright (C) 2013 Wolfram Sang <wsa@the-dreams.de>
	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
	25	static struct i2c_client of_i2c_register_device(struct i2c_adapter adap,
	26	struct device_node *node)
	27	{
	28	struct i2c_client *result;
	29	struct i2c_board_info info = {};
	30	struct dev_archdata dev_ad = {};
	31	const __be32 *addr_be;
	32	u32 addr;
	33	int len;
	34
	35	dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
	36
	37	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
	38	dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
	39	node->full_name);
	40	return ERR_PTR(-EINVAL);
	41	}
	42
	43	addr_be = of_get_property(node, "reg", &len);
	44	if (!addr_be \|\| (len < sizeof(*addr_be))) {
	45	dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
	46	node->full_name);
	47	return ERR_PTR(-EINVAL);
	48	}
	49
	50	addr = be32_to_cpup(addr_be);
	51	if (addr & I2C_TEN_BIT_ADDRESS) {
	52	addr &= ~I2C_TEN_BIT_ADDRESS;
	53	info.flags \|= I2C_CLIENT_TEN;
	54	}
	55
	56	if (addr & I2C_OWN_SLAVE_ADDRESS) {
	57	addr &= ~I2C_OWN_SLAVE_ADDRESS;
	58	info.flags \|= I2C_CLIENT_SLAVE;
	59	}
	60
	61	if (i2c_check_addr_validity(addr, info.flags)) {
	62	dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
	63	addr, node->full_name);
	64	return ERR_PTR(-EINVAL);
65	}
66
67	info.addr = addr;
68	info.of_node = of_node_get(node);
69	info.archdata = &dev_ad;
70
71	if (of_property_read_bool(node, "host-notify"))
72	info.flags \|= I2C_CLIENT_HOST_NOTIFY;
73
74	if (of_get_property(node, "wakeup-source", NULL))
75	info.flags \|= I2C_CLIENT_WAKE;
76
77	result = i2c_new_device(adap, &info);
78	if (result == NULL) {
79	dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
80	node->full_name);
81	of_node_put(node);
82	return ERR_PTR(-EINVAL);
83	}
84	return result;
85	}
86
87	void of_i2c_register_devices(struct i2c_adapter *adap)
88	{
89	struct device_node bus, node;
90	struct i2c_client *client;
91
92	/* Only register child devices if the adapter has a node pointer set */
93	if (!adap->dev.of_node)
94	return;
95
96	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
97
98	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
99	if (!bus)
100	bus = of_node_get(adap->dev.of_node);
101
102	for_each_available_child_of_node(bus, node) {
103	if (of_node_test_and_set_flag(node, OF_POPULATED))
104	continue;
105
106	client = of_i2c_register_device(adap, node);
107	if (IS_ERR(client)) {
108	dev_warn(&adap->dev,
109	"Failed to create I2C device for %s\n",
110	node->full_name);
111	of_node_clear_flag(node, OF_POPULATED);
112	}
113	}
114
115	of_node_put(bus);
116	}
117
118	static int of_dev_node_match(struct device dev, void data)
119	{
120	return dev->of_node == data;
121	}
122
123	/* must call put_device() when done with returned i2c_client device */
124	struct i2c_client of_find_i2c_device_by_node(struct device_node node)
125	{
126	struct device *dev;
127	struct i2c_client *client;
128
129	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
130	if (!dev)
131	return NULL;
132
133	client = i2c_verify_client(dev);
134	if (!client)
135	put_device(dev);
136
137	return client;
138	}
139	EXPORT_SYMBOL(of_find_i2c_device_by_node);
140
141	/* must call put_device() when done with returned i2c_adapter device */
142	struct i2c_adapter of_find_i2c_adapter_by_node(struct device_node node)
143	{
144	struct device *dev;
145	struct i2c_adapter *adapter;
146
147	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
148	if (!dev)
149	return NULL;
150
151	adapter = i2c_verify_adapter(dev);
152	if (!adapter)
153	put_device(dev);
154
155	return adapter;
156	}
157	EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
158
159	/* must call i2c_put_adapter() when done with returned i2c_adapter device */
160	struct i2c_adapter of_get_i2c_adapter_by_node(struct device_node node)
161	{
162	struct i2c_adapter *adapter;
163
164	adapter = of_find_i2c_adapter_by_node(node);
165	if (!adapter)
166	return NULL;
167
168	if (!try_module_get(adapter->owner)) {
169	put_device(&adapter->dev);
170	adapter = NULL;
171	}
172
173	return adapter;
174	}
175	EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
176
177	static const struct of_device_id*
178	i2c_of_match_device_sysfs(const struct of_device_id *matches,
179	struct i2c_client *client)
180	{
181	const char *name;
182
183	for (; matches->compatible[0]; matches++) {
184	/*
185	* Adding devices through the i2c sysfs interface provides us
186	* a string to match which may be compatible with the device
187	* tree compatible strings, however with no actual of_node the
188	* of_match_device() will not match
189	*/
190	if (sysfs_streq(client->name, matches->compatible))
191	return matches;
192
193	name = strchr(matches->compatible, ',');
194	if (!name)
195	name = matches->compatible;
196	else
197	name++;
198
199	if (sysfs_streq(client->name, name))
200	return matches;
201	}
202
203	return NULL;
204	}
205
206	const struct of_device_id
207	i2c_of_match_device(const struct of_device_id matches,
208	struct i2c_client *client)
209	{
210	const struct of_device_id *match;
211
212	if (!(client && matches))
213	return NULL;
214
215	match = of_match_device(matches, &client->dev);
216	if (match)
217	return match;
218
219	return i2c_of_match_device_sysfs(matches, client);
220	}
221	EXPORT_SYMBOL_GPL(i2c_of_match_device);
222
223	#if IS_ENABLED(CONFIG_OF_DYNAMIC)
224	static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
225	void *arg)
226	{
227	struct of_reconfig_data *rd = arg;
228	struct i2c_adapter *adap;
229	struct i2c_client *client;
230
231	switch (of_reconfig_get_state_change(action, rd)) {
232	case OF_RECONFIG_CHANGE_ADD:
233	adap = of_find_i2c_adapter_by_node(rd->dn->parent);
234	if (adap == NULL)
235	return NOTIFY_OK; /* not for us */
236
237	if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
238	put_device(&adap->dev);
239	return NOTIFY_OK;
240	}
241
242	client = of_i2c_register_device(adap, rd->dn);
243	put_device(&adap->dev);
244
245	if (IS_ERR(client)) {
246	dev_err(&adap->dev, "failed to create client for '%s'\n",
247	rd->dn->full_name);
248	of_node_clear_flag(rd->dn, OF_POPULATED);
249	return notifier_from_errno(PTR_ERR(client));
250	}
251	break;
252	case OF_RECONFIG_CHANGE_REMOVE:
253	/* already depopulated? */
254	if (!of_node_check_flag(rd->dn, OF_POPULATED))
255	return NOTIFY_OK;
256
257	/* find our device by node */
258	client = of_find_i2c_device_by_node(rd->dn);
259	if (client == NULL)
260	return NOTIFY_OK; /* no? not meant for us */
261
262	/* unregister takes one ref away */
263	i2c_unregister_device(client);
264
265	/* and put the reference of the find */
266	put_device(&client->dev);
267	break;
268	}
269
270	return NOTIFY_OK;
271	}
272
273	struct notifier_block i2c_of_notifier = {
274	.notifier_call = of_i2c_notify,
275	};
276	#endif /* CONFIG_OF_DYNAMIC */