[linux-block.git] / drivers / i2c / i2c-core-of.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Linux I2C core OF support code
 *
 * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
 * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
 *
 * Copyright (C) 2013, 2018 Wolfram Sang <wsa@kernel.org>
 */

#include <dt-bindings/i2c/i2c.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/sysfs.h>

#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 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 */
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
5bf4fa7d WS	2	/*
	3	* Linux I2C core OF support code
	4	*
	5	* Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
	6	* based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
	7	*
2f5a55c5	8	* Copyright (C) 2013, 2018 Wolfram Sang <wsa@kernel.org>
5bf4fa7d WS	9	*/
	10
	11	#include <dt-bindings/i2c/i2c.h>
	12	#include <linux/device.h>
	13	#include <linux/err.h>
	14	#include <linux/i2c.h>
	15	#include <linux/module.h>
	16	#include <linux/of.h>
	17	#include <linux/of_device.h>
a8023e66	18	#include <linux/sysfs.h>
5bf4fa7d WS	19
	20	#include "i2c-core.h"
	21
da0086d0 BB	22	int of_i2c_get_board_info(struct device dev, struct device_node node,
da0086d0 BB	23	struct i2c_board_info *info)
5bf4fa7d	24	{
5bf4fa7d	25	u32 addr;
a1671af2	26	int ret;
5bf4fa7d	27
da0086d0	28	memset(info, 0, sizeof(*info));
5bf4fa7d	29
da0086d0 BB	30	if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) {
	31	dev_err(dev, "of_i2c: modalias failure on %pOF\n", node);
	32	return -EINVAL;
5bf4fa7d WS	33	}
5bf4fa7d WS	34
a1671af2 WS	35	ret = of_property_read_u32(node, "reg", &addr);
a1671af2 WS	36	if (ret) {
da0086d0 BB	37	dev_err(dev, "of_i2c: invalid reg on %pOF\n", node);
da0086d0 BB	38	return ret;
5bf4fa7d WS	39	}
5bf4fa7d WS	40
5bf4fa7d WS	41	if (addr & I2C_TEN_BIT_ADDRESS) {
5bf4fa7d WS	42	addr &= ~I2C_TEN_BIT_ADDRESS;
da0086d0	43	info->flags \|= I2C_CLIENT_TEN;
5bf4fa7d WS	44	}
	45
	46	if (addr & I2C_OWN_SLAVE_ADDRESS) {
	47	addr &= ~I2C_OWN_SLAVE_ADDRESS;
da0086d0	48	info->flags \|= I2C_CLIENT_SLAVE;
5bf4fa7d WS	49	}
5bf4fa7d WS	50
da0086d0 BB	51	info->addr = addr;
da0086d0 BB	52	info->of_node = node;
60774d2a	53	info->fwnode = of_fwnode_handle(node);
5bf4fa7d WS	54
5bf4fa7d WS	55	if (of_property_read_bool(node, "host-notify"))
da0086d0	56	info->flags \|= I2C_CLIENT_HOST_NOTIFY;
5bf4fa7d WS	57
5bf4fa7d WS	58	if (of_get_property(node, "wakeup-source", NULL))
da0086d0 BB	59	info->flags \|= I2C_CLIENT_WAKE;
	60
	61	return 0;
	62	}
	63	EXPORT_SYMBOL_GPL(of_i2c_get_board_info);
	64
	65	static struct i2c_client of_i2c_register_device(struct i2c_adapter adap,
	66	struct device_node *node)
	67	{
	68	struct i2c_client *client;
	69	struct i2c_board_info info;
	70	int ret;
	71
	72	dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node);
	73
	74	ret = of_i2c_get_board_info(&adap->dev, node, &info);
	75	if (ret)
	76	return ERR_PTR(ret);
5bf4fa7d	77
5f0155b4 WS	78	client = i2c_new_client_device(adap, &info);
5f0155b4 WS	79	if (IS_ERR(client))
453a237c	80	dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node);
5f0155b4	81
c49b0e07	82	return client;
5bf4fa7d WS	83	}
	84
	85	void of_i2c_register_devices(struct i2c_adapter *adap)
	86	{
	87	struct device_node bus, node;
	88	struct i2c_client *client;
	89
	90	/* Only register child devices if the adapter has a node pointer set */
	91	if (!adap->dev.of_node)
	92	return;
	93
	94	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
	95
	96	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");
	97	if (!bus)
	98	bus = of_node_get(adap->dev.of_node);
	99
	100	for_each_available_child_of_node(bus, node) {
	101	if (of_node_test_and_set_flag(node, OF_POPULATED))
	102	continue;
	103
	104	client = of_i2c_register_device(adap, node);
	105	if (IS_ERR(client)) {
f1c87ceb	106	dev_err(&adap->dev,
453a237c RH	107	"Failed to create I2C device for %pOF\n",
453a237c RH	108	node);
5bf4fa7d WS	109	of_node_clear_flag(node, OF_POPULATED);
	110	}
	111	}
	112
	113	of_node_put(bus);
	114	}
	115
5bf4fa7d WS	116	static const struct of_device_id*
	117	i2c_of_match_device_sysfs(const struct of_device_id *matches,
	118	struct i2c_client *client)
	119	{
	120	const char *name;
	121
	122	for (; matches->compatible[0]; matches++) {
	123	/*
	124	* Adding devices through the i2c sysfs interface provides us
	125	* a string to match which may be compatible with the device
	126	* tree compatible strings, however with no actual of_node the
	127	* of_match_device() will not match
	128	*/
	129	if (sysfs_streq(client->name, matches->compatible))
	130	return matches;
	131
	132	name = strchr(matches->compatible, ',');
	133	if (!name)
	134	name = matches->compatible;
	135	else
	136	name++;
	137
	138	if (sysfs_streq(client->name, name))
	139	return matches;
	140	}
	141
	142	return NULL;
	143	}
	144
	145	const struct of_device_id
	146	i2c_of_match_device(const struct of_device_id matches,
	147	struct i2c_client *client)
	148	{
	149	const struct of_device_id *match;
	150
	151	if (!(client && matches))
	152	return NULL;
	153
	154	match = of_match_device(matches, &client->dev);
	155	if (match)
	156	return match;
	157
	158	return i2c_of_match_device_sysfs(matches, client);
	159	}
	160	EXPORT_SYMBOL_GPL(i2c_of_match_device);
	161
	162	#if IS_ENABLED(CONFIG_OF_DYNAMIC)
	163	static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
	164	void *arg)
	165	{
	166	struct of_reconfig_data *rd = arg;
	167	struct i2c_adapter *adap;
	168	struct i2c_client *client;
	169
	170	switch (of_reconfig_get_state_change(action, rd)) {
	171	case OF_RECONFIG_CHANGE_ADD:
	172	adap = of_find_i2c_adapter_by_node(rd->dn->parent);
	173	if (adap == NULL)
	174	return NOTIFY_OK; /* not for us */
	175
	176	if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
	177	put_device(&adap->dev);
	178	return NOTIFY_OK;
	179	}
180
181	client = of_i2c_register_device(adap, rd->dn);
5bf4fa7d	182	if (IS_ERR(client)) {
453a237c RH	183	dev_err(&adap->dev, "failed to create client for '%pOF'\n",
453a237c RH	184	rd->dn);
a4c2fec1	185	put_device(&adap->dev);
5bf4fa7d WS	186	of_node_clear_flag(rd->dn, OF_POPULATED);
	187	return notifier_from_errno(PTR_ERR(client));
	188	}
a4c2fec1	189	put_device(&adap->dev);
5bf4fa7d WS	190	break;
	191	case OF_RECONFIG_CHANGE_REMOVE:
	192	/* already depopulated? */
	193	if (!of_node_check_flag(rd->dn, OF_POPULATED))
	194	return NOTIFY_OK;
	195
	196	/* find our device by node */
	197	client = of_find_i2c_device_by_node(rd->dn);
	198	if (client == NULL)
	199	return NOTIFY_OK; /* no? not meant for us */
	200
	201	/* unregister takes one ref away */
	202	i2c_unregister_device(client);
	203
	204	/* and put the reference of the find */
	205	put_device(&client->dev);
	206	break;
	207	}
	208
	209	return NOTIFY_OK;
	210	}
	211
	212	struct notifier_block i2c_of_notifier = {
	213	.notifier_call = of_i2c_notify,
	214	};
	215	#endif /* CONFIG_OF_DYNAMIC */