2 * Linux I2C core OF support code
4 * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
5 * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
7 * Copyright (C) 2013 Wolfram Sang <wsa@the-dreams.de>
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)
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>
21 #include <linux/of_device.h>
25 static struct i2c_client
*of_i2c_register_device(struct i2c_adapter
*adap
,
26 struct device_node
*node
)
28 struct i2c_client
*result
;
29 struct i2c_board_info info
= {};
30 struct dev_archdata dev_ad
= {};
31 const __be32
*addr_be
;
35 dev_dbg(&adap
->dev
, "of_i2c: register %pOF\n", node
);
37 if (of_modalias_node(node
, info
.type
, sizeof(info
.type
)) < 0) {
38 dev_err(&adap
->dev
, "of_i2c: modalias failure on %pOF\n",
40 return ERR_PTR(-EINVAL
);
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 %pOF\n", node
);
46 return ERR_PTR(-EINVAL
);
49 addr
= be32_to_cpup(addr_be
);
50 if (addr
& I2C_TEN_BIT_ADDRESS
) {
51 addr
&= ~I2C_TEN_BIT_ADDRESS
;
52 info
.flags
|= I2C_CLIENT_TEN
;
55 if (addr
& I2C_OWN_SLAVE_ADDRESS
) {
56 addr
&= ~I2C_OWN_SLAVE_ADDRESS
;
57 info
.flags
|= I2C_CLIENT_SLAVE
;
60 if (i2c_check_addr_validity(addr
, info
.flags
)) {
61 dev_err(&adap
->dev
, "of_i2c: invalid addr=%x on %pOF\n",
63 return ERR_PTR(-EINVAL
);
67 info
.of_node
= of_node_get(node
);
68 info
.archdata
= &dev_ad
;
70 if (of_property_read_bool(node
, "host-notify"))
71 info
.flags
|= I2C_CLIENT_HOST_NOTIFY
;
73 if (of_get_property(node
, "wakeup-source", NULL
))
74 info
.flags
|= I2C_CLIENT_WAKE
;
76 result
= i2c_new_device(adap
, &info
);
78 dev_err(&adap
->dev
, "of_i2c: Failure registering %pOF\n", node
);
80 return ERR_PTR(-EINVAL
);
85 void of_i2c_register_devices(struct i2c_adapter
*adap
)
87 struct device_node
*bus
, *node
;
88 struct i2c_client
*client
;
90 /* Only register child devices if the adapter has a node pointer set */
91 if (!adap
->dev
.of_node
)
94 dev_dbg(&adap
->dev
, "of_i2c: walking child nodes\n");
96 bus
= of_get_child_by_name(adap
->dev
.of_node
, "i2c-bus");
98 bus
= of_node_get(adap
->dev
.of_node
);
100 for_each_available_child_of_node(bus
, node
) {
101 if (of_node_test_and_set_flag(node
, OF_POPULATED
))
104 client
= of_i2c_register_device(adap
, node
);
105 if (IS_ERR(client
)) {
107 "Failed to create I2C device for %pOF\n",
109 of_node_clear_flag(node
, OF_POPULATED
);
116 static int of_dev_node_match(struct device
*dev
, void *data
)
118 return dev
->of_node
== data
;
121 static int of_dev_or_parent_node_match(struct device
*dev
, void *data
)
123 if (dev
->of_node
== data
)
127 return dev
->parent
->of_node
== data
;
132 /* must call put_device() when done with returned i2c_client device */
133 struct i2c_client
*of_find_i2c_device_by_node(struct device_node
*node
)
136 struct i2c_client
*client
;
138 dev
= bus_find_device(&i2c_bus_type
, NULL
, node
, of_dev_node_match
);
142 client
= i2c_verify_client(dev
);
148 EXPORT_SYMBOL(of_find_i2c_device_by_node
);
150 /* must call put_device() when done with returned i2c_adapter device */
151 struct i2c_adapter
*of_find_i2c_adapter_by_node(struct device_node
*node
)
154 struct i2c_adapter
*adapter
;
156 dev
= bus_find_device(&i2c_bus_type
, NULL
, node
,
157 of_dev_or_parent_node_match
);
161 adapter
= i2c_verify_adapter(dev
);
167 EXPORT_SYMBOL(of_find_i2c_adapter_by_node
);
169 /* must call i2c_put_adapter() when done with returned i2c_adapter device */
170 struct i2c_adapter
*of_get_i2c_adapter_by_node(struct device_node
*node
)
172 struct i2c_adapter
*adapter
;
174 adapter
= of_find_i2c_adapter_by_node(node
);
178 if (!try_module_get(adapter
->owner
)) {
179 put_device(&adapter
->dev
);
185 EXPORT_SYMBOL(of_get_i2c_adapter_by_node
);
187 static const struct of_device_id
*
188 i2c_of_match_device_sysfs(const struct of_device_id
*matches
,
189 struct i2c_client
*client
)
193 for (; matches
->compatible
[0]; matches
++) {
195 * Adding devices through the i2c sysfs interface provides us
196 * a string to match which may be compatible with the device
197 * tree compatible strings, however with no actual of_node the
198 * of_match_device() will not match
200 if (sysfs_streq(client
->name
, matches
->compatible
))
203 name
= strchr(matches
->compatible
, ',');
205 name
= matches
->compatible
;
209 if (sysfs_streq(client
->name
, name
))
216 const struct of_device_id
217 *i2c_of_match_device(const struct of_device_id
*matches
,
218 struct i2c_client
*client
)
220 const struct of_device_id
*match
;
222 if (!(client
&& matches
))
225 match
= of_match_device(matches
, &client
->dev
);
229 return i2c_of_match_device_sysfs(matches
, client
);
231 EXPORT_SYMBOL_GPL(i2c_of_match_device
);
233 #if IS_ENABLED(CONFIG_OF_DYNAMIC)
234 static int of_i2c_notify(struct notifier_block
*nb
, unsigned long action
,
237 struct of_reconfig_data
*rd
= arg
;
238 struct i2c_adapter
*adap
;
239 struct i2c_client
*client
;
241 switch (of_reconfig_get_state_change(action
, rd
)) {
242 case OF_RECONFIG_CHANGE_ADD
:
243 adap
= of_find_i2c_adapter_by_node(rd
->dn
->parent
);
245 return NOTIFY_OK
; /* not for us */
247 if (of_node_test_and_set_flag(rd
->dn
, OF_POPULATED
)) {
248 put_device(&adap
->dev
);
252 client
= of_i2c_register_device(adap
, rd
->dn
);
253 if (IS_ERR(client
)) {
254 dev_err(&adap
->dev
, "failed to create client for '%pOF'\n",
256 put_device(&adap
->dev
);
257 of_node_clear_flag(rd
->dn
, OF_POPULATED
);
258 return notifier_from_errno(PTR_ERR(client
));
260 put_device(&adap
->dev
);
262 case OF_RECONFIG_CHANGE_REMOVE
:
263 /* already depopulated? */
264 if (!of_node_check_flag(rd
->dn
, OF_POPULATED
))
267 /* find our device by node */
268 client
= of_find_i2c_device_by_node(rd
->dn
);
270 return NOTIFY_OK
; /* no? not meant for us */
272 /* unregister takes one ref away */
273 i2c_unregister_device(client
);
275 /* and put the reference of the find */
276 put_device(&client
->dev
);
283 struct notifier_block i2c_of_notifier
= {
284 .notifier_call
= of_i2c_notify
,
286 #endif /* CONFIG_OF_DYNAMIC */