tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * OF helpers for the I2C API
3 *
4 * Copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
5 *
6 * Based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14#include <linux/i2c.h>
15#include <linux/irq.h>
16#include <linux/of.h>
17#include <linux/of_i2c.h>
18#include <linux/of_irq.h>
19#include <linux/module.h>
20
21void of_i2c_register_devices(struct i2c_adapter *adap)
22{
23 void *result;
24 struct device_node *node;
25
26 /* Only register child devices if the adapter has a node pointer set */
27 if (!adap->dev.of_node)
28 return;
29
30 dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
31
32 for_each_available_child_of_node(adap->dev.of_node, node) {
33 struct i2c_board_info info = {};
34 struct dev_archdata dev_ad = {};
35 const __be32 *addr;
36 int len;
37
38 dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
39
40 if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
41 dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
42 node->full_name);
43 continue;
44 }
45
46 addr = of_get_property(node, "reg", &len);
47 if (!addr || (len < sizeof(int))) {
48 dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
49 node->full_name);
50 continue;
51 }
52
53 info.addr = be32_to_cpup(addr);
54 if (info.addr > (1 << 10) - 1) {
55 dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
56 info.addr, node->full_name);
57 continue;
58 }
59
60 info.irq = irq_of_parse_and_map(node, 0);
61 info.of_node = of_node_get(node);
62 info.archdata = &dev_ad;
63
64 if (of_get_property(node, "wakeup-source", NULL))
65 info.flags |= I2C_CLIENT_WAKE;
66
67 request_module("%s%s", I2C_MODULE_PREFIX, info.type);
68
69 result = i2c_new_device(adap, &info);
70 if (result == NULL) {
71 dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
72 node->full_name);
73 of_node_put(node);
74 irq_dispose_mapping(info.irq);
75 continue;
76 }
77 }
78}
79EXPORT_SYMBOL(of_i2c_register_devices);
80
81static int of_dev_node_match(struct device *dev, void *data)
82{
83 return dev->of_node == data;
84}
85
86/* must call put_device() when done with returned i2c_client device */
87struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
88{
89 struct device *dev;
90
91 dev = bus_find_device(&i2c_bus_type, NULL, node,
92 of_dev_node_match);
93 if (!dev)
94 return NULL;
95
96 return i2c_verify_client(dev);
97}
98EXPORT_SYMBOL(of_find_i2c_device_by_node);
99
100/* must call put_device() when done with returned i2c_adapter device */
101struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
102{
103 struct device *dev;
104
105 dev = bus_find_device(&i2c_bus_type, NULL, node,
106 of_dev_node_match);
107 if (!dev)
108 return NULL;
109
110 return i2c_verify_adapter(dev);
111}
112EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
113
114MODULE_LICENSE("GPL");