// SPDX-License-Identifier: GPL-2.0-or-later /* * Linux I2C core OF support code * * Copyright (C) 2008 Jochen Friedrich * based on a previous patch from Jon Smirl * * Copyright (C) 2013, 2018 Wolfram Sang */ #include #include #include #include #include #include #include #include #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_modalias_node(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_get_property(node, "wakeup-source", NULL)) 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 int of_dev_or_parent_node_match(struct device *dev, const void *data) { if (dev->of_node == data) return 1; if (dev->parent) return dev->parent->of_node == data; return 0; } /* 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; struct i2c_client *client; dev = bus_find_device_by_of_node(&i2c_bus_type, node); if (!dev) return NULL; client = i2c_verify_client(dev); if (!client) put_device(dev); return client; } EXPORT_SYMBOL(of_find_i2c_device_by_node); /* must call put_device() when done with returned i2c_adapter device */ struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) { struct device *dev; struct i2c_adapter *adapter; dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_or_parent_node_match); if (!dev) return NULL; adapter = i2c_verify_adapter(dev); if (!adapter) put_device(dev); return adapter; } EXPORT_SYMBOL(of_find_i2c_adapter_by_node); /* must call i2c_put_adapter() when done with returned i2c_adapter device */ struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) { struct i2c_adapter *adapter; adapter = of_find_i2c_adapter_by_node(node); if (!adapter) return NULL; if (!try_module_get(adapter->owner)) { put_device(&adapter->dev); adapter = NULL; } return adapter; } EXPORT_SYMBOL(of_get_i2c_adapter_by_node); 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; } 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 */