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/*
* OF helpers for the I2C API
*
* Copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
*
* Based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
*
* 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 <linux/i2c.h>
#include <linux/of.h>
#include <linux/of_i2c.h>
#include <linux/module.h>
void of_register_i2c_devices(struct i2c_adapter *adap,
struct device_node *adap_node)
{
void *result;
struct device_node *node;
for_each_child_of_node(adap_node, node) {
struct i2c_board_info info = {};
struct dev_archdata dev_ad = {};
const __be32 *addr;
int len;
if (of_modalias_node(node, info.type, sizeof(info.type)) < 0)
continue;
addr = of_get_property(node, "reg", &len);
if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) {
printk(KERN_ERR
"of-i2c: invalid i2c device entry\n");
continue;
}
info.irq = irq_of_parse_and_map(node, 0);
info.addr = be32_to_cpup(addr);
dev_archdata_set_node(&dev_ad, node);
info.archdata = &dev_ad;
request_module("%s", info.type);
result = i2c_new_device(adap, &info);
if (result == NULL) {
printk(KERN_ERR
"of-i2c: Failed to load driver for %s\n",
info.type);
irq_dispose_mapping(info.irq);
continue;
}
/*
* Get the node to not lose the dev_archdata->of_node.
* Currently there is no way to put it back, as well as no
* of_unregister_i2c_devices() call.
*/
of_node_get(node);
}
}
EXPORT_SYMBOL(of_register_i2c_devices);
static int of_dev_node_match(struct device *dev, void *data)
{
return dev_archdata_get_node(&dev->archdata) == 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;
dev = bus_find_device(&i2c_bus_type, NULL, node,
of_dev_node_match);
if (!dev)
return NULL;
return to_i2c_client(dev);
}
EXPORT_SYMBOL(of_find_i2c_device_by_node);
MODULE_LICENSE("GPL");
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