1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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, 2018 Wolfram Sang <wsa@kernel.org>
*/
#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 <linux/sysfs.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_alias_from_compatible(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;
info->fwnode = of_fwnode_handle(node);
if (of_property_read_bool(node, "host-notify"))
info->flags |= I2C_CLIENT_HOST_NOTIFY;
if (of_property_read_bool(node, "wakeup-source"))
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_client_device(adap, &info);
if (IS_ERR(client))
dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
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 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;
}
/*
* Clear the flag before adding the device so that fw_devlink
* doesn't skip adding consumers to this device.
*/
rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
client = of_i2c_register_device(adap, rd->dn);
if (IS_ERR(client)) {
dev_err(&adap->dev, "failed to create client for '%pOF'\n",
rd->dn);
put_device(&adap->dev);
of_node_clear_flag(rd->dn, OF_POPULATED);
return notifier_from_errno(PTR_ERR(client));
}
put_device(&adap->dev);
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 */
|
