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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Linux I2C core OF support code
4 *
5 * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
6 * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
7 *
8 * Copyright (C) 2013, 2018 Wolfram Sang <wsa@kernel.org>
9 */
10
11#include <dt-bindings/i2c/i2c.h>
12#include <linux/device.h>
13#include <linux/err.h>
14#include <linux/i2c.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_device.h>
18#include <linux/sysfs.h>
19
20#include "i2c-core.h"
21
22int of_i2c_get_board_info(struct device *dev, struct device_node *node,
23 struct i2c_board_info *info)
24{
25 u32 addr;
26 int ret;
27
28 memset(info, 0, sizeof(*info));
29
30 if (of_alias_from_compatible(node, info->type, sizeof(info->type)) < 0) {
31 dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
32 return -EINVAL;
33 }
34
35 ret = of_property_read_u32(node, "reg", &addr);
36 if (ret) {
37 dev_err(dev, "of_i2c: invalid reg on %pOF\n", node);
38 return ret;
39 }
40
41 if (addr & I2C_TEN_BIT_ADDRESS) {
42 addr &= ~I2C_TEN_BIT_ADDRESS;
43 info->flags |= I2C_CLIENT_TEN;
44 }
45
46 if (addr & I2C_OWN_SLAVE_ADDRESS) {
47 addr &= ~I2C_OWN_SLAVE_ADDRESS;
48 info->flags |= I2C_CLIENT_SLAVE;
49 }
50
51 info->addr = addr;
52 info->of_node = node;
53 info->fwnode = of_fwnode_handle(node);
54
55 if (of_property_read_bool(node, "host-notify"))
56 info->flags |= I2C_CLIENT_HOST_NOTIFY;
57
58 if (of_property_read_bool(node, "wakeup-source"))
59 info->flags |= I2C_CLIENT_WAKE;
60
61 return 0;
62}
63EXPORT_SYMBOL_GPL(of_i2c_get_board_info);
64
65static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
66 struct device_node *node)
67{
68 struct i2c_client *client;
69 struct i2c_board_info info;
70 int ret;
71
72 dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);
73
74 ret = of_i2c_get_board_info(&adap->dev, node, &info);
75 if (ret)
76 return ERR_PTR(ret);
77
78 client = i2c_new_client_device(adap, &info);
79 if (IS_ERR(client))
80 dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
81
82 return client;
83}
84
85void of_i2c_register_devices(struct i2c_adapter *adap)
86{
87 struct device_node *bus, *node;
88 struct i2c_client *client;
89
90 /* Only register child devices if the adapter has a node pointer set */
91 if (!adap->dev.of_node)
92 return;
93
94 dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
95
96 bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
97 if (!bus)
98 bus = of_node_get(adap->dev.of_node);
99
100 for_each_available_child_of_node(bus, node) {
101 if (of_node_test_and_set_flag(node, OF_POPULATED))
102 continue;
103
104 client = of_i2c_register_device(adap, node);
105 if (IS_ERR(client)) {
106 dev_err(&adap->dev,
107 "Failed to create I2C device for %pOF\n",
108 node);
109 of_node_clear_flag(node, OF_POPULATED);
110 }
111 }
112
113 of_node_put(bus);
114}
115
116static const struct of_device_id*
117i2c_of_match_device_sysfs(const struct of_device_id *matches,
118 struct i2c_client *client)
119{
120 const char *name;
121
122 for (; matches->compatible[0]; matches++) {
123 /*
124 * Adding devices through the i2c sysfs interface provides us
125 * a string to match which may be compatible with the device
126 * tree compatible strings, however with no actual of_node the
127 * of_match_device() will not match
128 */
129 if (sysfs_streq(client->name, matches->compatible))
130 return matches;
131
132 name = strchr(matches->compatible, ',');
133 if (!name)
134 name = matches->compatible;
135 else
136 name++;
137
138 if (sysfs_streq(client->name, name))
139 return matches;
140 }
141
142 return NULL;
143}
144
145const struct of_device_id
146*i2c_of_match_device(const struct of_device_id *matches,
147 struct i2c_client *client)
148{
149 const struct of_device_id *match;
150
151 if (!(client && matches))
152 return NULL;
153
154 match = of_match_device(matches, &client->dev);
155 if (match)
156 return match;
157
158 return i2c_of_match_device_sysfs(matches, client);
159}
160EXPORT_SYMBOL_GPL(i2c_of_match_device);
161
162#if IS_ENABLED(CONFIG_OF_DYNAMIC)
163static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
164 void *arg)
165{
166 struct of_reconfig_data *rd = arg;
167 struct i2c_adapter *adap;
168 struct i2c_client *client;
169
170 switch (of_reconfig_get_state_change(action, rd)) {
171 case OF_RECONFIG_CHANGE_ADD:
172 adap = of_find_i2c_adapter_by_node(rd->dn->parent);
173 if (adap == NULL)
174 return NOTIFY_OK; /* not for us */
175
176 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
177 put_device(&adap->dev);
178 return NOTIFY_OK;
179 }
180
181 /*
182 * Clear the flag before adding the device so that fw_devlink
183 * doesn't skip adding consumers to this device.
184 */
185 rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
186 client = of_i2c_register_device(adap, rd->dn);
187 if (IS_ERR(client)) {
188 dev_err(&adap->dev, "failed to create client for '%pOF'\n",
189 rd->dn);
190 put_device(&adap->dev);
191 of_node_clear_flag(rd->dn, OF_POPULATED);
192 return notifier_from_errno(PTR_ERR(client));
193 }
194 put_device(&adap->dev);
195 break;
196 case OF_RECONFIG_CHANGE_REMOVE:
197 /* already depopulated? */
198 if (!of_node_check_flag(rd->dn, OF_POPULATED))
199 return NOTIFY_OK;
200
201 /* find our device by node */
202 client = of_find_i2c_device_by_node(rd->dn);
203 if (client == NULL)
204 return NOTIFY_OK; /* no? not meant for us */
205
206 /* unregister takes one ref away */
207 i2c_unregister_device(client);
208
209 /* and put the reference of the find */
210 put_device(&client->dev);
211 break;
212 }
213
214 return NOTIFY_OK;
215}
216
217struct notifier_block i2c_of_notifier = {
218 .notifier_call = of_i2c_notify,
219};
220#endif /* CONFIG_OF_DYNAMIC */
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, 2018 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
25static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
26 struct device_node *node)
27{
28 struct i2c_client *client;
29 struct i2c_board_info info = {};
30 struct dev_archdata dev_ad = {};
31 u32 addr;
32 int ret;
33
34 dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);
35
36 if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
37 dev_err(&adap->dev, "of_i2c: modalias failure on %pOF\n",
38 node);
39 return ERR_PTR(-EINVAL);
40 }
41
42 ret = of_property_read_u32(node, "reg", &addr);
43 if (ret) {
44 dev_err(&adap->dev, "of_i2c: invalid reg on %pOF\n", node);
45 return ERR_PTR(ret);
46 }
47
48 if (addr & I2C_TEN_BIT_ADDRESS) {
49 addr &= ~I2C_TEN_BIT_ADDRESS;
50 info.flags |= I2C_CLIENT_TEN;
51 }
52
53 if (addr & I2C_OWN_SLAVE_ADDRESS) {
54 addr &= ~I2C_OWN_SLAVE_ADDRESS;
55 info.flags |= I2C_CLIENT_SLAVE;
56 }
57
58 info.addr = addr;
59 info.archdata = &dev_ad;
60 info.of_node = of_node_get(node);
61
62 if (of_property_read_bool(node, "host-notify"))
63 info.flags |= I2C_CLIENT_HOST_NOTIFY;
64
65 if (of_get_property(node, "wakeup-source", NULL))
66 info.flags |= I2C_CLIENT_WAKE;
67
68 client = i2c_new_device(adap, &info);
69 if (!client) {
70 dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
71 of_node_put(node);
72 return ERR_PTR(-EINVAL);
73 }
74 return client;
75}
76
77void of_i2c_register_devices(struct i2c_adapter *adap)
78{
79 struct device_node *bus, *node;
80 struct i2c_client *client;
81
82 /* Only register child devices if the adapter has a node pointer set */
83 if (!adap->dev.of_node)
84 return;
85
86 dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
87
88 bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
89 if (!bus)
90 bus = of_node_get(adap->dev.of_node);
91
92 for_each_available_child_of_node(bus, node) {
93 if (of_node_test_and_set_flag(node, OF_POPULATED))
94 continue;
95
96 client = of_i2c_register_device(adap, node);
97 if (IS_ERR(client)) {
98 dev_err(&adap->dev,
99 "Failed to create I2C device for %pOF\n",
100 node);
101 of_node_clear_flag(node, OF_POPULATED);
102 }
103 }
104
105 of_node_put(bus);
106}
107
108static int of_dev_node_match(struct device *dev, void *data)
109{
110 return dev->of_node == data;
111}
112
113/* must call put_device() when done with returned i2c_client device */
114struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
115{
116 struct device *dev;
117 struct i2c_client *client;
118
119 dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
120 if (!dev)
121 return NULL;
122
123 client = i2c_verify_client(dev);
124 if (!client)
125 put_device(dev);
126
127 return client;
128}
129EXPORT_SYMBOL(of_find_i2c_device_by_node);
130
131/* must call put_device() when done with returned i2c_adapter device */
132struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
133{
134 struct device *dev;
135 struct i2c_adapter *adapter;
136
137 dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
138 if (!dev)
139 return NULL;
140
141 adapter = i2c_verify_adapter(dev);
142 if (!adapter)
143 put_device(dev);
144
145 return adapter;
146}
147EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
148
149/* must call i2c_put_adapter() when done with returned i2c_adapter device */
150struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
151{
152 struct i2c_adapter *adapter;
153
154 adapter = of_find_i2c_adapter_by_node(node);
155 if (!adapter)
156 return NULL;
157
158 if (!try_module_get(adapter->owner)) {
159 put_device(&adapter->dev);
160 adapter = NULL;
161 }
162
163 return adapter;
164}
165EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
166
167static const struct of_device_id*
168i2c_of_match_device_sysfs(const struct of_device_id *matches,
169 struct i2c_client *client)
170{
171 const char *name;
172
173 for (; matches->compatible[0]; matches++) {
174 /*
175 * Adding devices through the i2c sysfs interface provides us
176 * a string to match which may be compatible with the device
177 * tree compatible strings, however with no actual of_node the
178 * of_match_device() will not match
179 */
180 if (sysfs_streq(client->name, matches->compatible))
181 return matches;
182
183 name = strchr(matches->compatible, ',');
184 if (!name)
185 name = matches->compatible;
186 else
187 name++;
188
189 if (sysfs_streq(client->name, name))
190 return matches;
191 }
192
193 return NULL;
194}
195
196const struct of_device_id
197*i2c_of_match_device(const struct of_device_id *matches,
198 struct i2c_client *client)
199{
200 const struct of_device_id *match;
201
202 if (!(client && matches))
203 return NULL;
204
205 match = of_match_device(matches, &client->dev);
206 if (match)
207 return match;
208
209 return i2c_of_match_device_sysfs(matches, client);
210}
211EXPORT_SYMBOL_GPL(i2c_of_match_device);
212
213#if IS_ENABLED(CONFIG_OF_DYNAMIC)
214static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
215 void *arg)
216{
217 struct of_reconfig_data *rd = arg;
218 struct i2c_adapter *adap;
219 struct i2c_client *client;
220
221 switch (of_reconfig_get_state_change(action, rd)) {
222 case OF_RECONFIG_CHANGE_ADD:
223 adap = of_find_i2c_adapter_by_node(rd->dn->parent);
224 if (adap == NULL)
225 return NOTIFY_OK; /* not for us */
226
227 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
228 put_device(&adap->dev);
229 return NOTIFY_OK;
230 }
231
232 client = of_i2c_register_device(adap, rd->dn);
233 put_device(&adap->dev);
234
235 if (IS_ERR(client)) {
236 dev_err(&adap->dev, "failed to create client for '%pOF'\n",
237 rd->dn);
238 of_node_clear_flag(rd->dn, OF_POPULATED);
239 return notifier_from_errno(PTR_ERR(client));
240 }
241 break;
242 case OF_RECONFIG_CHANGE_REMOVE:
243 /* already depopulated? */
244 if (!of_node_check_flag(rd->dn, OF_POPULATED))
245 return NOTIFY_OK;
246
247 /* find our device by node */
248 client = of_find_i2c_device_by_node(rd->dn);
249 if (client == NULL)
250 return NOTIFY_OK; /* no? not meant for us */
251
252 /* unregister takes one ref away */
253 i2c_unregister_device(client);
254
255 /* and put the reference of the find */
256 put_device(&client->dev);
257 break;
258 }
259
260 return NOTIFY_OK;
261}
262
263struct notifier_block i2c_of_notifier = {
264 .notifier_call = of_i2c_notify,
265};
266#endif /* CONFIG_OF_DYNAMIC */