| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 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 | |
| 21 | void 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_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 | request_module("%s%s", I2C_MODULE_PREFIX, info.type); |
| 65 | |
| 66 | result = i2c_new_device(adap, &info); |
| 67 | if (result == NULL) { |
| 68 | dev_err(&adap->dev, "of_i2c: Failure registering %s\n", |
| 69 | node->full_name); |
| 70 | of_node_put(node); |
| 71 | irq_dispose_mapping(info.irq); |
| 72 | continue; |
| 73 | } |
| 74 | } |
| 75 | } |
| 76 | EXPORT_SYMBOL(of_i2c_register_devices); |
| 77 | |
| 78 | static int of_dev_node_match(struct device *dev, void *data) |
| 79 | { |
| 80 | return dev->of_node == data; |
| 81 | } |
| 82 | |
| 83 | /* must call put_device() when done with returned i2c_client device */ |
| 84 | struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) |
| 85 | { |
| 86 | struct device *dev; |
| 87 | |
| 88 | dev = bus_find_device(&i2c_bus_type, NULL, node, |
| 89 | of_dev_node_match); |
| 90 | if (!dev) |
| 91 | return NULL; |
| 92 | |
| 93 | return to_i2c_client(dev); |
| 94 | } |
| 95 | EXPORT_SYMBOL(of_find_i2c_device_by_node); |
| 96 | |
| 97 | MODULE_LICENSE("GPL"); |