media: i2c: add I2C Address Translator (ATR) support

An ATR is a device that looks similar to an i2c-mux: it has an I2C
slave "upstream" port and N master "downstream" ports, and forwards
transactions from upstream to the appropriate downstream port. But it
is different in that the forwarded transaction has a different slave
address. The address used on the upstream bus is called the "alias"
and is (potentially) different from the physical slave address of the
downstream chip.

Add a helper file (just like i2c-mux.c for a mux or switch) to allow
implementing ATR features in a device driver. The helper takes care of
adapter creation/destruction and translates addresses at each transaction.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

1 files changed, 710 insertions, 0 deletions

diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c
new file mode 100644
index 000000000000..8ca1daadec93
--- /dev/null
+++ b/drivers/i2c/i2c-atr.c
@@ -0,0 +1,710 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * I2C Address Translator
+ *
+ * Copyright (c) 2019,2022 Luca Ceresoli <luca@lucaceresoli.net>
+ * Copyright (c) 2022,2023 Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
+ *
+ * Originally based on i2c-mux.c
+ */
+
+#include <linux/fwnode.h>
+#include <linux/i2c-atr.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#define ATR_MAX_ADAPTERS 100	/* Just a sanity limit */
+#define ATR_MAX_SYMLINK_LEN 11	/* Longest name is 10 chars: "channel-99" */
+
+/**
+ * struct i2c_atr_alias_pair - Holds the alias assigned to a client.
+ * @node:   List node
+ * @client: Pointer to the client on the child bus
+ * @alias:  I2C alias address assigned by the driver.
+ *          This is the address that will be used to issue I2C transactions
+ *          on the parent (physical) bus.
+ */
+struct i2c_atr_alias_pair {
+	struct list_head node;
+	const struct i2c_client *client;
+	u16 alias;
+};
+
+/**
+ * struct i2c_atr_chan - Data for a channel.
+ * @adap:            The &struct i2c_adapter for the channel
+ * @atr:             The parent I2C ATR
+ * @chan_id:         The ID of this channel
+ * @alias_list:      List of @struct i2c_atr_alias_pair containing the
+ *                   assigned aliases
+ * @orig_addrs_lock: Mutex protecting @orig_addrs
+ * @orig_addrs:      Buffer used to store the original addresses during transmit
+ * @orig_addrs_size: Size of @orig_addrs
+ */
+struct i2c_atr_chan {
+	struct i2c_adapter adap;
+	struct i2c_atr *atr;
+	u32 chan_id;
+
+	struct list_head alias_list;
+
+	/* Lock orig_addrs during xfer */
+	struct mutex orig_addrs_lock;
+	u16 *orig_addrs;
+	unsigned int orig_addrs_size;
+};
+
+/**
+ * struct i2c_atr - The I2C ATR instance
+ * @parent:    The parent &struct i2c_adapter
+ * @dev:       The device that owns the I2C ATR instance
+ * @ops:       &struct i2c_atr_ops
+ * @priv:      Private driver data, set with i2c_atr_set_driver_data()
+ * @algo:      The &struct i2c_algorithm for adapters
+ * @lock:      Lock for the I2C bus segment (see &struct i2c_lock_operations)
+ * @max_adapters: Maximum number of adapters this I2C ATR can have
+ * @num_aliases: Number of aliases in the aliases array
+ * @aliases:   The aliases array
+ * @alias_mask_lock: Lock protecting alias_use_mask
+ * @alias_use_mask: Bitmask for used aliases in aliases array
+ * @i2c_nb:    Notifier for remote client add & del events
+ * @adapter:   Array of adapters
+ */
+struct i2c_atr {
+	struct i2c_adapter *parent;
+	struct device *dev;
+	const struct i2c_atr_ops *ops;
+
+	void *priv;
+
+	struct i2c_algorithm algo;
+	/* lock for the I2C bus segment (see struct i2c_lock_operations) */
+	struct mutex lock;
+	int max_adapters;
+
+	size_t num_aliases;
+	const u16 *aliases;
+	/* Protects alias_use_mask */
+	spinlock_t alias_mask_lock;
+	unsigned long *alias_use_mask;
+
+	struct notifier_block i2c_nb;
+
+	struct i2c_adapter *adapter[];
+};
+
+static struct i2c_atr_alias_pair *
+i2c_atr_find_mapping_by_client(const struct list_head *list,
+			       const struct i2c_client *client)
+{
+	struct i2c_atr_alias_pair *c2a;
+
+	list_for_each_entry(c2a, list, node) {
+		if (c2a->client == client)
+			return c2a;
+	}
+
+	return NULL;
+}
+
+static struct i2c_atr_alias_pair *
+i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr)
+{
+	struct i2c_atr_alias_pair *c2a;
+
+	list_for_each_entry(c2a, list, node) {
+		if (c2a->client->addr == phys_addr)
+			return c2a;
+	}
+
+	return NULL;
+}
+
+/*
+ * Replace all message addresses with their aliases, saving the original
+ * addresses.
+ *
+ * This function is internal for use in i2c_atr_master_xfer(). It must be
+ * followed by i2c_atr_unmap_msgs() to restore the original addresses.
+ */
+static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
+			    int num)
+{
+	struct i2c_atr *atr = chan->atr;
+	static struct i2c_atr_alias_pair *c2a;
+	int i;
+
+	/* Ensure we have enough room to save the original addresses */
+	if (unlikely(chan->orig_addrs_size < num)) {
+		u16 *new_buf;
+
+		/* We don't care about old data, hence no realloc() */
+		new_buf = kmalloc_array(num, sizeof(*new_buf), GFP_KERNEL);
+		if (!new_buf)
+			return -ENOMEM;
+
+		kfree(chan->orig_addrs);
+		chan->orig_addrs = new_buf;
+		chan->orig_addrs_size = num;
+	}
+
+	for (i = 0; i < num; i++) {
+		chan->orig_addrs[i] = msgs[i].addr;
+
+		c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list,
+						   msgs[i].addr);
+		if (!c2a) {
+			dev_err(atr->dev, "client 0x%02x not mapped!\n",
+				msgs[i].addr);
+
+			while (i--)
+				msgs[i].addr = chan->orig_addrs[i];
+
+			return -ENXIO;
+		}
+
+		msgs[i].addr = c2a->alias;
+	}
+
+	return 0;
+}
+
+/*
+ * Restore all message address aliases with the original addresses. This
+ * function is internal for use in i2c_atr_master_xfer() and for this reason it
+ * needs no null and size checks on orig_addr.
+ *
+ * @see i2c_atr_map_msgs()
+ */
+static void i2c_atr_unmap_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
+			       int num)
+{
+	int i;
+
+	for (i = 0; i < num; i++)
+		msgs[i].addr = chan->orig_addrs[i];
+}
+
+static int i2c_atr_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+			       int num)
+{
+	struct i2c_atr_chan *chan = adap->algo_data;
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_adapter *parent = atr->parent;
+	int ret;
+
+	/* Translate addresses */
+	mutex_lock(&chan->orig_addrs_lock);
+
+	ret = i2c_atr_map_msgs(chan, msgs, num);
+	if (ret < 0)
+		goto err_unlock;
+
+	/* Perform the transfer */
+	ret = i2c_transfer(parent, msgs, num);
+
+	/* Restore addresses */
+	i2c_atr_unmap_msgs(chan, msgs, num);
+
+err_unlock:
+	mutex_unlock(&chan->orig_addrs_lock);
+
+	return ret;
+}
+
+static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+			      unsigned short flags, char read_write, u8 command,
+			      int size, union i2c_smbus_data *data)
+{
+	struct i2c_atr_chan *chan = adap->algo_data;
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_adapter *parent = atr->parent;
+	struct i2c_atr_alias_pair *c2a;
+
+	c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr);
+	if (!c2a) {
+		dev_err(atr->dev, "client 0x%02x not mapped!\n", addr);
+		return -ENXIO;
+	}
+
+	return i2c_smbus_xfer(parent, c2a->alias, flags, read_write, command,
+			      size, data);
+}
+
+static u32 i2c_atr_functionality(struct i2c_adapter *adap)
+{
+	struct i2c_atr_chan *chan = adap->algo_data;
+	struct i2c_adapter *parent = chan->atr->parent;
+
+	return parent->algo->functionality(parent);
+}
+
+static void i2c_atr_lock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+	struct i2c_atr_chan *chan = adapter->algo_data;
+	struct i2c_atr *atr = chan->atr;
+
+	mutex_lock(&atr->lock);
+}
+
+static int i2c_atr_trylock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+	struct i2c_atr_chan *chan = adapter->algo_data;
+	struct i2c_atr *atr = chan->atr;
+
+	return mutex_trylock(&atr->lock);
+}
+
+static void i2c_atr_unlock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+	struct i2c_atr_chan *chan = adapter->algo_data;
+	struct i2c_atr *atr = chan->atr;
+
+	mutex_unlock(&atr->lock);
+}
+
+static const struct i2c_lock_operations i2c_atr_lock_ops = {
+	.lock_bus =    i2c_atr_lock_bus,
+	.trylock_bus = i2c_atr_trylock_bus,
+	.unlock_bus =  i2c_atr_unlock_bus,
+};
+
+static int i2c_atr_reserve_alias(struct i2c_atr *atr)
+{
+	unsigned long idx;
+
+	spin_lock(&atr->alias_mask_lock);
+
+	idx = find_first_zero_bit(atr->alias_use_mask, atr->num_aliases);
+	if (idx >= atr->num_aliases) {
+		spin_unlock(&atr->alias_mask_lock);
+		dev_err(atr->dev, "failed to find a free alias\n");
+		return -EBUSY;
+	}
+
+	set_bit(idx, atr->alias_use_mask);
+
+	spin_unlock(&atr->alias_mask_lock);
+
+	return atr->aliases[idx];
+}
+
+static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias)
+{
+	unsigned int idx;
+
+	spin_lock(&atr->alias_mask_lock);
+
+	for (idx = 0; idx < atr->num_aliases; ++idx) {
+		if (atr->aliases[idx] == alias) {
+			clear_bit(idx, atr->alias_use_mask);
+			spin_unlock(&atr->alias_mask_lock);
+			return;
+		}
+	}
+
+	spin_unlock(&atr->alias_mask_lock);
+
+	 /* This should never happen */
+	dev_warn(atr->dev, "Unable to find mapped alias\n");
+}
+
+static int i2c_atr_attach_client(struct i2c_adapter *adapter,
+				 const struct i2c_client *client)
+{
+	struct i2c_atr_chan *chan = adapter->algo_data;
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_atr_alias_pair *c2a;
+	u16 alias;
+	int ret;
+
+	ret = i2c_atr_reserve_alias(atr);
+	if (ret < 0)
+		return ret;
+
+	alias = ret;
+
+	c2a = kzalloc(sizeof(*c2a), GFP_KERNEL);
+	if (!c2a) {
+		ret = -ENOMEM;
+		goto err_release_alias;
+	}
+
+	ret = atr->ops->attach_client(atr, chan->chan_id, client, alias);
+	if (ret)
+		goto err_free;
+
+	dev_dbg(atr->dev, "chan%u: client 0x%02x mapped at alias 0x%02x (%s)\n",
+		chan->chan_id, client->addr, alias, client->name);
+
+	c2a->client = client;
+	c2a->alias = alias;
+	list_add(&c2a->node, &chan->alias_list);
+
+	return 0;
+
+err_free:
+	kfree(c2a);
+err_release_alias:
+	i2c_atr_release_alias(atr, alias);
+
+	return ret;
+}
+
+static void i2c_atr_detach_client(struct i2c_adapter *adapter,
+				  const struct i2c_client *client)
+{
+	struct i2c_atr_chan *chan = adapter->algo_data;
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_atr_alias_pair *c2a;
+
+	atr->ops->detach_client(atr, chan->chan_id, client);
+
+	c2a = i2c_atr_find_mapping_by_client(&chan->alias_list, client);
+	if (!c2a) {
+		 /* This should never happen */
+		dev_warn(atr->dev, "Unable to find address mapping\n");
+		return;
+	}
+
+	i2c_atr_release_alias(atr, c2a->alias);
+
+	dev_dbg(atr->dev,
+		"chan%u: client 0x%02x unmapped from alias 0x%02x (%s)\n",
+		chan->chan_id, client->addr, c2a->alias, client->name);
+
+	list_del(&c2a->node);
+	kfree(c2a);
+}
+
+static int i2c_atr_bus_notifier_call(struct notifier_block *nb,
+				     unsigned long event, void *device)
+{
+	struct i2c_atr *atr = container_of(nb, struct i2c_atr, i2c_nb);
+	struct device *dev = device;
+	struct i2c_client *client;
+	u32 chan_id;
+	int ret;
+
+	client = i2c_verify_client(dev);
+	if (!client)
+		return NOTIFY_DONE;
+
+	/* Is the client in one of our adapters? */
+	for (chan_id = 0; chan_id < atr->max_adapters; ++chan_id) {
+		if (client->adapter == atr->adapter[chan_id])
+			break;
+	}
+
+	if (chan_id == atr->max_adapters)
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case BUS_NOTIFY_ADD_DEVICE:
+		ret = i2c_atr_attach_client(client->adapter, client);
+		if (ret)
+			dev_err(atr->dev,
+				"Failed to attach remote client '%s': %d\n",
+				dev_name(dev), ret);
+		break;
+
+	case BUS_NOTIFY_DEL_DEVICE:
+		i2c_atr_detach_client(client->adapter, client);
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int i2c_atr_parse_alias_pool(struct i2c_atr *atr)
+{
+	struct device *dev = atr->dev;
+	unsigned long *alias_use_mask;
+	size_t num_aliases;
+	unsigned int i;
+	u32 *aliases32;
+	u16 *aliases16;
+	int ret;
+
+	ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool");
+	if (ret < 0) {
+		dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n",
+			ret);
+		return ret;
+	}
+
+	num_aliases = ret;
+
+	if (!num_aliases)
+		return 0;
+
+	aliases32 = kcalloc(num_aliases, sizeof(*aliases32), GFP_KERNEL);
+	if (!aliases32)
+		return -ENOMEM;
+
+	ret = fwnode_property_read_u32_array(dev_fwnode(dev), "i2c-alias-pool",
+					     aliases32, num_aliases);
+	if (ret < 0) {
+		dev_err(dev, "Failed to read 'i2c-alias-pool' property: %d\n",
+			ret);
+		goto err_free_aliases32;
+	}
+
+	aliases16 = kcalloc(num_aliases, sizeof(*aliases16), GFP_KERNEL);
+	if (!aliases16) {
+		ret = -ENOMEM;
+		goto err_free_aliases32;
+	}
+
+	for (i = 0; i < num_aliases; i++) {
+		if (!(aliases32[i] & 0xffff0000)) {
+			aliases16[i] = aliases32[i];
+			continue;
+		}
+
+		dev_err(dev, "Failed to parse 'i2c-alias-pool' property: I2C flags are not supported\n");
+		ret = -EINVAL;
+		goto err_free_aliases16;
+	}
+
+	alias_use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL);
+	if (!alias_use_mask) {
+		ret = -ENOMEM;
+		goto err_free_aliases16;
+	}
+
+	kfree(aliases32);
+
+	atr->num_aliases = num_aliases;
+	atr->aliases = aliases16;
+	atr->alias_use_mask = alias_use_mask;
+
+	dev_dbg(dev, "i2c-alias-pool has %zu aliases", atr->num_aliases);
+
+	return 0;
+
+err_free_aliases16:
+	kfree(aliases16);
+err_free_aliases32:
+	kfree(aliases32);
+	return ret;
+}
+
+struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
+			    const struct i2c_atr_ops *ops, int max_adapters)
+{
+	struct i2c_atr *atr;
+	int ret;
+
+	if (max_adapters > ATR_MAX_ADAPTERS)
+		return ERR_PTR(-EINVAL);
+
+	if (!ops || !ops->attach_client || !ops->detach_client)
+		return ERR_PTR(-EINVAL);
+
+	atr = kzalloc(struct_size(atr, adapter, max_adapters), GFP_KERNEL);
+	if (!atr)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_init(&atr->lock);
+	spin_lock_init(&atr->alias_mask_lock);
+
+	atr->parent = parent;
+	atr->dev = dev;
+	atr->ops = ops;
+	atr->max_adapters = max_adapters;
+
+	if (parent->algo->master_xfer)
+		atr->algo.master_xfer = i2c_atr_master_xfer;
+	if (parent->algo->smbus_xfer)
+		atr->algo.smbus_xfer = i2c_atr_smbus_xfer;
+	atr->algo.functionality = i2c_atr_functionality;
+
+	ret = i2c_atr_parse_alias_pool(atr);
+	if (ret)
+		goto err_destroy_mutex;
+
+	atr->i2c_nb.notifier_call = i2c_atr_bus_notifier_call;
+	ret = bus_register_notifier(&i2c_bus_type, &atr->i2c_nb);
+	if (ret)
+		goto err_free_aliases;
+
+	return atr;
+
+err_free_aliases:
+	bitmap_free(atr->alias_use_mask);
+	kfree(atr->aliases);
+err_destroy_mutex:
+	mutex_destroy(&atr->lock);
+	kfree(atr);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_new, I2C_ATR);
+
+void i2c_atr_delete(struct i2c_atr *atr)
+{
+	unsigned int i;
+
+	for (i = 0; i < atr->max_adapters; ++i)
+		WARN_ON(atr->adapter[i]);
+
+	bus_unregister_notifier(&i2c_bus_type, &atr->i2c_nb);
+	bitmap_free(atr->alias_use_mask);
+	kfree(atr->aliases);
+	mutex_destroy(&atr->lock);
+	kfree(atr);
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_delete, I2C_ATR);
+
+int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
+			struct device *adapter_parent,
+			struct fwnode_handle *bus_handle)
+{
+	struct i2c_adapter *parent = atr->parent;
+	struct device *dev = atr->dev;
+	struct i2c_atr_chan *chan;
+	char symlink_name[ATR_MAX_SYMLINK_LEN];
+	int ret;
+
+	if (chan_id >= atr->max_adapters) {
+		dev_err(dev, "No room for more i2c-atr adapters\n");
+		return -EINVAL;
+	}
+
+	if (atr->adapter[chan_id]) {
+		dev_err(dev, "Adapter %d already present\n", chan_id);
+		return -EEXIST;
+	}
+
+	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
+	if (!chan)
+		return -ENOMEM;
+
+	if (!adapter_parent)
+		adapter_parent = dev;
+
+	chan->atr = atr;
+	chan->chan_id = chan_id;
+	INIT_LIST_HEAD(&chan->alias_list);
+	mutex_init(&chan->orig_addrs_lock);
+
+	snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d",
+		 i2c_adapter_id(parent), chan_id);
+	chan->adap.owner = THIS_MODULE;
+	chan->adap.algo = &atr->algo;
+	chan->adap.algo_data = chan;
+	chan->adap.dev.parent = adapter_parent;
+	chan->adap.retries = parent->retries;
+	chan->adap.timeout = parent->timeout;
+	chan->adap.quirks = parent->quirks;
+	chan->adap.lock_ops = &i2c_atr_lock_ops;
+
+	if (bus_handle) {
+		device_set_node(&chan->adap.dev, fwnode_handle_get(bus_handle));
+	} else {
+		struct fwnode_handle *atr_node;
+		struct fwnode_handle *child;
+		u32 reg;
+
+		atr_node = device_get_named_child_node(dev, "i2c-atr");
+
+		fwnode_for_each_child_node(atr_node, child) {
+			ret = fwnode_property_read_u32(child, "reg", &reg);
+			if (ret)
+				continue;
+			if (chan_id == reg)
+				break;
+		}
+
+		device_set_node(&chan->adap.dev, child);
+		fwnode_handle_put(atr_node);
+	}
+
+	atr->adapter[chan_id] = &chan->adap;
+
+	ret = i2c_add_adapter(&chan->adap);
+	if (ret) {
+		dev_err(dev, "failed to add atr-adapter %u (error=%d)\n",
+			chan_id, ret);
+		goto err_fwnode_put;
+	}
+
+	snprintf(symlink_name, sizeof(symlink_name), "channel-%u",
+		 chan->chan_id);
+
+	ret = sysfs_create_link(&chan->adap.dev.kobj, &dev->kobj, "atr_device");
+	if (ret)
+		dev_warn(dev, "can't create symlink to atr device\n");
+	ret = sysfs_create_link(&dev->kobj, &chan->adap.dev.kobj, symlink_name);
+	if (ret)
+		dev_warn(dev, "can't create symlink for channel %u\n", chan_id);
+
+	dev_dbg(dev, "Added ATR child bus %d\n", i2c_adapter_id(&chan->adap));
+
+	return 0;
+
+err_fwnode_put:
+	fwnode_handle_put(dev_fwnode(&chan->adap.dev));
+	mutex_destroy(&chan->orig_addrs_lock);
+	kfree(chan);
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_add_adapter, I2C_ATR);
+
+void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id)
+{
+	char symlink_name[ATR_MAX_SYMLINK_LEN];
+	struct i2c_adapter *adap;
+	struct i2c_atr_chan *chan;
+	struct fwnode_handle *fwnode;
+	struct device *dev = atr->dev;
+
+	adap = atr->adapter[chan_id];
+	if (!adap)
+		return;
+
+	chan = adap->algo_data;
+	fwnode = dev_fwnode(&adap->dev);
+
+	dev_dbg(dev, "Removing ATR child bus %d\n", i2c_adapter_id(adap));
+
+	snprintf(symlink_name, sizeof(symlink_name), "channel-%u",
+		 chan->chan_id);
+	sysfs_remove_link(&dev->kobj, symlink_name);
+	sysfs_remove_link(&chan->adap.dev.kobj, "atr_device");
+
+	i2c_del_adapter(adap);
+
+	atr->adapter[chan_id] = NULL;
+
+	fwnode_handle_put(fwnode);
+	mutex_destroy(&chan->orig_addrs_lock);
+	kfree(chan->orig_addrs);
+	kfree(chan);
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_del_adapter, I2C_ATR);
+
+void i2c_atr_set_driver_data(struct i2c_atr *atr, void *data)
+{
+	atr->priv = data;
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_set_driver_data, I2C_ATR);
+
+void *i2c_atr_get_driver_data(struct i2c_atr *atr)
+{
+	return atr->priv;
+}
+EXPORT_SYMBOL_NS_GPL(i2c_atr_get_driver_data, I2C_ATR);
+
+MODULE_AUTHOR("Luca Ceresoli <luca.ceresoli@bootlin.com>");
+MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>");
+MODULE_DESCRIPTION("I2C Address Translator");
+MODULE_LICENSE("GPL");