xref: /linux/drivers/i2c/i2c-core-of.c (revision a1671af2863376abb9f200c5db3c9097c0490e87)
15bf4fa7dSWolfram Sang /*
25bf4fa7dSWolfram Sang  * Linux I2C core OF support code
35bf4fa7dSWolfram Sang  *
45bf4fa7dSWolfram Sang  * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
55bf4fa7dSWolfram Sang  * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
65bf4fa7dSWolfram Sang  *
7*a1671af2SWolfram Sang  * Copyright (C) 2013, 2018 Wolfram Sang <wsa@the-dreams.de>
85bf4fa7dSWolfram Sang  *
95bf4fa7dSWolfram Sang  * This program is free software; you can redistribute it and/or modify it
105bf4fa7dSWolfram Sang  * under the terms of the GNU General Public License as published by the Free
115bf4fa7dSWolfram Sang  * Software Foundation; either version 2 of the License, or (at your option)
125bf4fa7dSWolfram Sang  * any later version.
135bf4fa7dSWolfram Sang  */
145bf4fa7dSWolfram Sang 
155bf4fa7dSWolfram Sang #include <dt-bindings/i2c/i2c.h>
165bf4fa7dSWolfram Sang #include <linux/device.h>
175bf4fa7dSWolfram Sang #include <linux/err.h>
185bf4fa7dSWolfram Sang #include <linux/i2c.h>
195bf4fa7dSWolfram Sang #include <linux/module.h>
205bf4fa7dSWolfram Sang #include <linux/of.h>
215bf4fa7dSWolfram Sang #include <linux/of_device.h>
225bf4fa7dSWolfram Sang 
235bf4fa7dSWolfram Sang #include "i2c-core.h"
245bf4fa7dSWolfram Sang 
255bf4fa7dSWolfram Sang static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
265bf4fa7dSWolfram Sang 						 struct device_node *node)
275bf4fa7dSWolfram Sang {
28c49b0e07SWolfram Sang 	struct i2c_client *client;
295bf4fa7dSWolfram Sang 	struct i2c_board_info info = {};
305bf4fa7dSWolfram Sang 	struct dev_archdata dev_ad = {};
315bf4fa7dSWolfram Sang 	u32 addr;
32*a1671af2SWolfram Sang 	int ret;
335bf4fa7dSWolfram Sang 
34453a237cSRob Herring 	dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);
355bf4fa7dSWolfram Sang 
365bf4fa7dSWolfram Sang 	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
37453a237cSRob Herring 		dev_err(&adap->dev, "of_i2c: modalias failure on %pOF\n",
38453a237cSRob Herring 			node);
395bf4fa7dSWolfram Sang 		return ERR_PTR(-EINVAL);
405bf4fa7dSWolfram Sang 	}
415bf4fa7dSWolfram Sang 
42*a1671af2SWolfram Sang 	ret = of_property_read_u32(node, "reg", &addr);
43*a1671af2SWolfram Sang 	if (ret) {
44453a237cSRob Herring 		dev_err(&adap->dev, "of_i2c: invalid reg on %pOF\n", node);
45*a1671af2SWolfram Sang 		return ERR_PTR(ret);
465bf4fa7dSWolfram Sang 	}
475bf4fa7dSWolfram Sang 
485bf4fa7dSWolfram Sang 	if (addr & I2C_TEN_BIT_ADDRESS) {
495bf4fa7dSWolfram Sang 		addr &= ~I2C_TEN_BIT_ADDRESS;
505bf4fa7dSWolfram Sang 		info.flags |= I2C_CLIENT_TEN;
515bf4fa7dSWolfram Sang 	}
525bf4fa7dSWolfram Sang 
535bf4fa7dSWolfram Sang 	if (addr & I2C_OWN_SLAVE_ADDRESS) {
545bf4fa7dSWolfram Sang 		addr &= ~I2C_OWN_SLAVE_ADDRESS;
555bf4fa7dSWolfram Sang 		info.flags |= I2C_CLIENT_SLAVE;
565bf4fa7dSWolfram Sang 	}
575bf4fa7dSWolfram Sang 
585bf4fa7dSWolfram Sang 	info.addr = addr;
595bf4fa7dSWolfram Sang 	info.archdata = &dev_ad;
60e6db2d32SWolfram Sang 	info.of_node = of_node_get(node);
615bf4fa7dSWolfram Sang 
625bf4fa7dSWolfram Sang 	if (of_property_read_bool(node, "host-notify"))
635bf4fa7dSWolfram Sang 		info.flags |= I2C_CLIENT_HOST_NOTIFY;
645bf4fa7dSWolfram Sang 
655bf4fa7dSWolfram Sang 	if (of_get_property(node, "wakeup-source", NULL))
665bf4fa7dSWolfram Sang 		info.flags |= I2C_CLIENT_WAKE;
675bf4fa7dSWolfram Sang 
68c49b0e07SWolfram Sang 	client = i2c_new_device(adap, &info);
69c49b0e07SWolfram Sang 	if (!client) {
70453a237cSRob Herring 		dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
715bf4fa7dSWolfram Sang 		of_node_put(node);
725bf4fa7dSWolfram Sang 		return ERR_PTR(-EINVAL);
735bf4fa7dSWolfram Sang 	}
74c49b0e07SWolfram Sang 	return client;
755bf4fa7dSWolfram Sang }
765bf4fa7dSWolfram Sang 
775bf4fa7dSWolfram Sang void of_i2c_register_devices(struct i2c_adapter *adap)
785bf4fa7dSWolfram Sang {
795bf4fa7dSWolfram Sang 	struct device_node *bus, *node;
805bf4fa7dSWolfram Sang 	struct i2c_client *client;
815bf4fa7dSWolfram Sang 
825bf4fa7dSWolfram Sang 	/* Only register child devices if the adapter has a node pointer set */
835bf4fa7dSWolfram Sang 	if (!adap->dev.of_node)
845bf4fa7dSWolfram Sang 		return;
855bf4fa7dSWolfram Sang 
865bf4fa7dSWolfram Sang 	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
875bf4fa7dSWolfram Sang 
885bf4fa7dSWolfram Sang 	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
895bf4fa7dSWolfram Sang 	if (!bus)
905bf4fa7dSWolfram Sang 		bus = of_node_get(adap->dev.of_node);
915bf4fa7dSWolfram Sang 
925bf4fa7dSWolfram Sang 	for_each_available_child_of_node(bus, node) {
935bf4fa7dSWolfram Sang 		if (of_node_test_and_set_flag(node, OF_POPULATED))
945bf4fa7dSWolfram Sang 			continue;
955bf4fa7dSWolfram Sang 
965bf4fa7dSWolfram Sang 		client = of_i2c_register_device(adap, node);
975bf4fa7dSWolfram Sang 		if (IS_ERR(client)) {
98f1c87cebSWolfram Sang 			dev_err(&adap->dev,
99453a237cSRob Herring 				 "Failed to create I2C device for %pOF\n",
100453a237cSRob Herring 				 node);
1015bf4fa7dSWolfram Sang 			of_node_clear_flag(node, OF_POPULATED);
1025bf4fa7dSWolfram Sang 		}
1035bf4fa7dSWolfram Sang 	}
1045bf4fa7dSWolfram Sang 
1055bf4fa7dSWolfram Sang 	of_node_put(bus);
1065bf4fa7dSWolfram Sang }
1075bf4fa7dSWolfram Sang 
1085bf4fa7dSWolfram Sang static int of_dev_node_match(struct device *dev, void *data)
1095bf4fa7dSWolfram Sang {
1105bf4fa7dSWolfram Sang 	return dev->of_node == data;
1115bf4fa7dSWolfram Sang }
1125bf4fa7dSWolfram Sang 
1135bf4fa7dSWolfram Sang /* must call put_device() when done with returned i2c_client device */
1145bf4fa7dSWolfram Sang struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
1155bf4fa7dSWolfram Sang {
1165bf4fa7dSWolfram Sang 	struct device *dev;
1175bf4fa7dSWolfram Sang 	struct i2c_client *client;
1185bf4fa7dSWolfram Sang 
1195bf4fa7dSWolfram Sang 	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
1205bf4fa7dSWolfram Sang 	if (!dev)
1215bf4fa7dSWolfram Sang 		return NULL;
1225bf4fa7dSWolfram Sang 
1235bf4fa7dSWolfram Sang 	client = i2c_verify_client(dev);
1245bf4fa7dSWolfram Sang 	if (!client)
1255bf4fa7dSWolfram Sang 		put_device(dev);
1265bf4fa7dSWolfram Sang 
1275bf4fa7dSWolfram Sang 	return client;
1285bf4fa7dSWolfram Sang }
1295bf4fa7dSWolfram Sang EXPORT_SYMBOL(of_find_i2c_device_by_node);
1305bf4fa7dSWolfram Sang 
1315bf4fa7dSWolfram Sang /* must call put_device() when done with returned i2c_adapter device */
1325bf4fa7dSWolfram Sang struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
1335bf4fa7dSWolfram Sang {
1345bf4fa7dSWolfram Sang 	struct device *dev;
1355bf4fa7dSWolfram Sang 	struct i2c_adapter *adapter;
1365bf4fa7dSWolfram Sang 
1375bf4fa7dSWolfram Sang 	dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
1385bf4fa7dSWolfram Sang 	if (!dev)
1395bf4fa7dSWolfram Sang 		return NULL;
1405bf4fa7dSWolfram Sang 
1415bf4fa7dSWolfram Sang 	adapter = i2c_verify_adapter(dev);
1425bf4fa7dSWolfram Sang 	if (!adapter)
1435bf4fa7dSWolfram Sang 		put_device(dev);
1445bf4fa7dSWolfram Sang 
1455bf4fa7dSWolfram Sang 	return adapter;
1465bf4fa7dSWolfram Sang }
1475bf4fa7dSWolfram Sang EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
1485bf4fa7dSWolfram Sang 
1495bf4fa7dSWolfram Sang /* must call i2c_put_adapter() when done with returned i2c_adapter device */
1505bf4fa7dSWolfram Sang struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
1515bf4fa7dSWolfram Sang {
1525bf4fa7dSWolfram Sang 	struct i2c_adapter *adapter;
1535bf4fa7dSWolfram Sang 
1545bf4fa7dSWolfram Sang 	adapter = of_find_i2c_adapter_by_node(node);
1555bf4fa7dSWolfram Sang 	if (!adapter)
1565bf4fa7dSWolfram Sang 		return NULL;
1575bf4fa7dSWolfram Sang 
1585bf4fa7dSWolfram Sang 	if (!try_module_get(adapter->owner)) {
1595bf4fa7dSWolfram Sang 		put_device(&adapter->dev);
1605bf4fa7dSWolfram Sang 		adapter = NULL;
1615bf4fa7dSWolfram Sang 	}
1625bf4fa7dSWolfram Sang 
1635bf4fa7dSWolfram Sang 	return adapter;
1645bf4fa7dSWolfram Sang }
1655bf4fa7dSWolfram Sang EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
1665bf4fa7dSWolfram Sang 
1675bf4fa7dSWolfram Sang static const struct of_device_id*
1685bf4fa7dSWolfram Sang i2c_of_match_device_sysfs(const struct of_device_id *matches,
1695bf4fa7dSWolfram Sang 				  struct i2c_client *client)
1705bf4fa7dSWolfram Sang {
1715bf4fa7dSWolfram Sang 	const char *name;
1725bf4fa7dSWolfram Sang 
1735bf4fa7dSWolfram Sang 	for (; matches->compatible[0]; matches++) {
1745bf4fa7dSWolfram Sang 		/*
1755bf4fa7dSWolfram Sang 		 * Adding devices through the i2c sysfs interface provides us
1765bf4fa7dSWolfram Sang 		 * a string to match which may be compatible with the device
1775bf4fa7dSWolfram Sang 		 * tree compatible strings, however with no actual of_node the
1785bf4fa7dSWolfram Sang 		 * of_match_device() will not match
1795bf4fa7dSWolfram Sang 		 */
1805bf4fa7dSWolfram Sang 		if (sysfs_streq(client->name, matches->compatible))
1815bf4fa7dSWolfram Sang 			return matches;
1825bf4fa7dSWolfram Sang 
1835bf4fa7dSWolfram Sang 		name = strchr(matches->compatible, ',');
1845bf4fa7dSWolfram Sang 		if (!name)
1855bf4fa7dSWolfram Sang 			name = matches->compatible;
1865bf4fa7dSWolfram Sang 		else
1875bf4fa7dSWolfram Sang 			name++;
1885bf4fa7dSWolfram Sang 
1895bf4fa7dSWolfram Sang 		if (sysfs_streq(client->name, name))
1905bf4fa7dSWolfram Sang 			return matches;
1915bf4fa7dSWolfram Sang 	}
1925bf4fa7dSWolfram Sang 
1935bf4fa7dSWolfram Sang 	return NULL;
1945bf4fa7dSWolfram Sang }
1955bf4fa7dSWolfram Sang 
1965bf4fa7dSWolfram Sang const struct of_device_id
1975bf4fa7dSWolfram Sang *i2c_of_match_device(const struct of_device_id *matches,
1985bf4fa7dSWolfram Sang 		     struct i2c_client *client)
1995bf4fa7dSWolfram Sang {
2005bf4fa7dSWolfram Sang 	const struct of_device_id *match;
2015bf4fa7dSWolfram Sang 
2025bf4fa7dSWolfram Sang 	if (!(client && matches))
2035bf4fa7dSWolfram Sang 		return NULL;
2045bf4fa7dSWolfram Sang 
2055bf4fa7dSWolfram Sang 	match = of_match_device(matches, &client->dev);
2065bf4fa7dSWolfram Sang 	if (match)
2075bf4fa7dSWolfram Sang 		return match;
2085bf4fa7dSWolfram Sang 
2095bf4fa7dSWolfram Sang 	return i2c_of_match_device_sysfs(matches, client);
2105bf4fa7dSWolfram Sang }
2115bf4fa7dSWolfram Sang EXPORT_SYMBOL_GPL(i2c_of_match_device);
2125bf4fa7dSWolfram Sang 
2135bf4fa7dSWolfram Sang #if IS_ENABLED(CONFIG_OF_DYNAMIC)
2145bf4fa7dSWolfram Sang static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
2155bf4fa7dSWolfram Sang 			 void *arg)
2165bf4fa7dSWolfram Sang {
2175bf4fa7dSWolfram Sang 	struct of_reconfig_data *rd = arg;
2185bf4fa7dSWolfram Sang 	struct i2c_adapter *adap;
2195bf4fa7dSWolfram Sang 	struct i2c_client *client;
2205bf4fa7dSWolfram Sang 
2215bf4fa7dSWolfram Sang 	switch (of_reconfig_get_state_change(action, rd)) {
2225bf4fa7dSWolfram Sang 	case OF_RECONFIG_CHANGE_ADD:
2235bf4fa7dSWolfram Sang 		adap = of_find_i2c_adapter_by_node(rd->dn->parent);
2245bf4fa7dSWolfram Sang 		if (adap == NULL)
2255bf4fa7dSWolfram Sang 			return NOTIFY_OK;	/* not for us */
2265bf4fa7dSWolfram Sang 
2275bf4fa7dSWolfram Sang 		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
2285bf4fa7dSWolfram Sang 			put_device(&adap->dev);
2295bf4fa7dSWolfram Sang 			return NOTIFY_OK;
2305bf4fa7dSWolfram Sang 		}
2315bf4fa7dSWolfram Sang 
2325bf4fa7dSWolfram Sang 		client = of_i2c_register_device(adap, rd->dn);
2335bf4fa7dSWolfram Sang 		put_device(&adap->dev);
2345bf4fa7dSWolfram Sang 
2355bf4fa7dSWolfram Sang 		if (IS_ERR(client)) {
236453a237cSRob Herring 			dev_err(&adap->dev, "failed to create client for '%pOF'\n",
237453a237cSRob Herring 				 rd->dn);
2385bf4fa7dSWolfram Sang 			of_node_clear_flag(rd->dn, OF_POPULATED);
2395bf4fa7dSWolfram Sang 			return notifier_from_errno(PTR_ERR(client));
2405bf4fa7dSWolfram Sang 		}
2415bf4fa7dSWolfram Sang 		break;
2425bf4fa7dSWolfram Sang 	case OF_RECONFIG_CHANGE_REMOVE:
2435bf4fa7dSWolfram Sang 		/* already depopulated? */
2445bf4fa7dSWolfram Sang 		if (!of_node_check_flag(rd->dn, OF_POPULATED))
2455bf4fa7dSWolfram Sang 			return NOTIFY_OK;
2465bf4fa7dSWolfram Sang 
2475bf4fa7dSWolfram Sang 		/* find our device by node */
2485bf4fa7dSWolfram Sang 		client = of_find_i2c_device_by_node(rd->dn);
2495bf4fa7dSWolfram Sang 		if (client == NULL)
2505bf4fa7dSWolfram Sang 			return NOTIFY_OK;	/* no? not meant for us */
2515bf4fa7dSWolfram Sang 
2525bf4fa7dSWolfram Sang 		/* unregister takes one ref away */
2535bf4fa7dSWolfram Sang 		i2c_unregister_device(client);
2545bf4fa7dSWolfram Sang 
2555bf4fa7dSWolfram Sang 		/* and put the reference of the find */
2565bf4fa7dSWolfram Sang 		put_device(&client->dev);
2575bf4fa7dSWolfram Sang 		break;
2585bf4fa7dSWolfram Sang 	}
2595bf4fa7dSWolfram Sang 
2605bf4fa7dSWolfram Sang 	return NOTIFY_OK;
2615bf4fa7dSWolfram Sang }
2625bf4fa7dSWolfram Sang 
2635bf4fa7dSWolfram Sang struct notifier_block i2c_of_notifier = {
2645bf4fa7dSWolfram Sang 	.notifier_call = of_i2c_notify,
2655bf4fa7dSWolfram Sang };
2665bf4fa7dSWolfram Sang #endif /* CONFIG_OF_DYNAMIC */
267