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/of.h> 16#include <linux/of_i2c.h> 17#include <linux/of_irq.h> 18#include <linux/module.h> 19 20void of_i2c_register_devices(struct i2c_adapter *adap) 21{ 22 void *result; 23 struct device_node *node; 24 25 /* Only register child devices if the adapter has a node pointer set */ 26 if (!adap->dev.of_node) 27 return; 28 29 dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); 30 31 for_each_child_of_node(adap->dev.of_node, node) { 32 struct i2c_board_info info = {}; 33 struct dev_archdata dev_ad = {}; 34 const __be32 *addr; 35 int len; 36 37 dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name); 38 39 if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) { 40 dev_err(&adap->dev, "of_i2c: modalias failure on %s\n", 41 node->full_name); 42 continue; 43 } 44 45 addr = of_get_property(node, "reg", &len); 46 if (!addr || (len < sizeof(int))) { 47 dev_err(&adap->dev, "of_i2c: invalid reg on %s\n", 48 node->full_name); 49 continue; 50 } 51 52 info.addr = be32_to_cpup(addr); 53 if (info.addr > (1 << 10) - 1) { 54 dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n", 55 info.addr, node->full_name); 56 continue; 57 } 58 59 info.irq = irq_of_parse_and_map(node, 0); 60 info.of_node = of_node_get(node); 61 info.archdata = &dev_ad; 62 63 request_module("%s", info.type); 64 65 result = i2c_new_device(adap, &info); 66 if (result == NULL) { 67 dev_err(&adap->dev, "of_i2c: Failure registering %s\n", 68 node->full_name); 69 of_node_put(node); 70 irq_dispose_mapping(info.irq); 71 continue; 72 } 73 } 74} 75EXPORT_SYMBOL(of_i2c_register_devices); 76 77static int of_dev_node_match(struct device *dev, void *data) 78{ 79 return dev->of_node == data; 80} 81 82/* must call put_device() when done with returned i2c_client device */ 83struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) 84{ 85 struct device *dev; 86 87 dev = bus_find_device(&i2c_bus_type, NULL, node, 88 of_dev_node_match); 89 if (!dev) 90 return NULL; 91 92 return to_i2c_client(dev); 93} 94EXPORT_SYMBOL(of_find_i2c_device_by_node); 95 96MODULE_LICENSE("GPL"); 97