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// 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 */
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