1 files changed, 408 insertions, 164 deletions

diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c
index 8fe9ddff8e96..be7d6d41e0b2 100644
--- a/drivers/i2c/i2c-atr.c
+++ b/drivers/i2c/i2c-atr.c
@@ -8,40 +8,73 @@
  * 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/property.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/lockdep.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.
+ * struct i2c_atr_alias_pair - Holds the alias assigned to a client address.
  * @node:   List node
- * @client: Pointer to the client on the child bus
+ * @addr:   Address of 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.
+ * @fixed:  Alias pair cannot be replaced during dynamic address attachment.
+ *          This flag is necessary for situations where a single I2C transaction
+ *          contains more distinct target addresses than the ATR channel can handle.
+ *          It marks addresses that have already been attached to an alias so
+ *          that their alias pair is not evicted by a subsequent address in the same
+ *          transaction.
+ *
  */
 struct i2c_atr_alias_pair {
 	struct list_head node;
-	const struct i2c_client *client;
+	bool fixed;
+	u16 addr;
 	u16 alias;
 };
 
 /**
+ * struct i2c_atr_alias_pool - Pool of client aliases available for an ATR.
+ * @size:     Total number of aliases
+ * @shared:   Indicates if this alias pool is shared by multiple channels
+ *
+ * @lock:     Lock protecting @aliases and @use_mask
+ * @aliases:  Array of aliases, must hold exactly @size elements
+ * @use_mask: Mask of used aliases
+ */
+struct i2c_atr_alias_pool {
+	size_t size;
+	bool shared;
+
+	/* Protects aliases and use_mask */
+	spinlock_t lock;
+	u16 *aliases;
+	unsigned long *use_mask;
+};
+
+/**
  * 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
+ * @alias_pairs_lock: Mutex protecting @alias_pairs
+ * @alias_pairs_lock_key: Lock key for @alias_pairs_lock
+ * @alias_pairs:     List of @struct i2c_atr_alias_pair containing the
  *                   assigned aliases
+ * @alias_pool:      Pool of available client aliases
+ *
  * @orig_addrs_lock: Mutex protecting @orig_addrs
+ * @orig_addrs_lock_key: Lock key for @orig_addrs_lock
  * @orig_addrs:      Buffer used to store the original addresses during transmit
  * @orig_addrs_size: Size of @orig_addrs
  */
@@ -50,10 +83,15 @@ struct i2c_atr_chan {
 	struct i2c_atr *atr;
 	u32 chan_id;
 
-	struct list_head alias_list;
+	/* Lock alias_pairs during attach/detach */
+	struct mutex alias_pairs_lock;
+	struct lock_class_key alias_pairs_lock_key;
+	struct list_head alias_pairs;
+	struct i2c_atr_alias_pool *alias_pool;
 
 	/* Lock orig_addrs during xfer */
 	struct mutex orig_addrs_lock;
+	struct lock_class_key orig_addrs_lock_key;
 	u16 *orig_addrs;
 	unsigned int orig_addrs_size;
 };
@@ -66,11 +104,10 @@ struct i2c_atr_chan {
  * @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)
+ * @lock_key:  Lock key for @lock
  * @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
+ * @flags:     Flags for ATR
+ * @alias_pool: Optional common pool of available client aliases
  * @i2c_nb:    Notifier for remote client add & del events
  * @adapter:   Array of adapters
  */
@@ -84,27 +121,135 @@ struct i2c_atr {
 	struct i2c_algorithm algo;
 	/* lock for the I2C bus segment (see struct i2c_lock_operations) */
 	struct mutex lock;
+	struct lock_class_key lock_key;
 	int max_adapters;
+	u32 flags;
 
-	size_t num_aliases;
-	const u16 *aliases;
-	/* Protects alias_use_mask */
-	spinlock_t alias_mask_lock;
-	unsigned long *alias_use_mask;
+	struct i2c_atr_alias_pool *alias_pool;
 
 	struct notifier_block i2c_nb;
 
 	struct i2c_adapter *adapter[] __counted_by(max_adapters);
 };
 
+static struct i2c_atr_alias_pool *i2c_atr_alloc_alias_pool(size_t num_aliases, bool shared)
+{
+	struct i2c_atr_alias_pool *alias_pool;
+	int ret;
+
+	alias_pool = kzalloc(sizeof(*alias_pool), GFP_KERNEL);
+	if (!alias_pool)
+		return ERR_PTR(-ENOMEM);
+
+	alias_pool->size = num_aliases;
+
+	alias_pool->aliases = kcalloc(num_aliases, sizeof(*alias_pool->aliases), GFP_KERNEL);
+	if (!alias_pool->aliases) {
+		ret = -ENOMEM;
+		goto err_free_alias_pool;
+	}
+
+	alias_pool->use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL);
+	if (!alias_pool->use_mask) {
+		ret = -ENOMEM;
+		goto err_free_aliases;
+	}
+
+	alias_pool->shared = shared;
+
+	spin_lock_init(&alias_pool->lock);
+
+	return alias_pool;
+
+err_free_aliases:
+	kfree(alias_pool->aliases);
+err_free_alias_pool:
+	kfree(alias_pool);
+	return ERR_PTR(ret);
+}
+
+static void i2c_atr_free_alias_pool(struct i2c_atr_alias_pool *alias_pool)
+{
+	bitmap_free(alias_pool->use_mask);
+	kfree(alias_pool->aliases);
+	kfree(alias_pool);
+}
+
+/* Must be called with alias_pairs_lock held */
+static struct i2c_atr_alias_pair *i2c_atr_create_c2a(struct i2c_atr_chan *chan,
+						     u16 alias, u16 addr)
+{
+	struct i2c_atr_alias_pair *c2a;
+
+	lockdep_assert_held(&chan->alias_pairs_lock);
+
+	c2a = kzalloc(sizeof(*c2a), GFP_KERNEL);
+	if (!c2a)
+		return NULL;
+
+	c2a->addr = addr;
+	c2a->alias = alias;
+
+	list_add(&c2a->node, &chan->alias_pairs);
+
+	return c2a;
+}
+
+/* Must be called with alias_pairs_lock held */
+static void i2c_atr_destroy_c2a(struct i2c_atr_alias_pair **pc2a)
+{
+	list_del(&(*pc2a)->node);
+	kfree(*pc2a);
+	*pc2a = NULL;
+}
+
+static int i2c_atr_reserve_alias(struct i2c_atr_alias_pool *alias_pool)
+{
+	unsigned long idx;
+	u16 alias;
+
+	spin_lock(&alias_pool->lock);
+
+	idx = find_first_zero_bit(alias_pool->use_mask, alias_pool->size);
+	if (idx >= alias_pool->size) {
+		spin_unlock(&alias_pool->lock);
+		return -EBUSY;
+	}
+
+	set_bit(idx, alias_pool->use_mask);
+
+	alias = alias_pool->aliases[idx];
+
+	spin_unlock(&alias_pool->lock);
+	return alias;
+}
+
+static void i2c_atr_release_alias(struct i2c_atr_alias_pool *alias_pool, u16 alias)
+{
+	unsigned int idx;
+
+	spin_lock(&alias_pool->lock);
+
+	for (idx = 0; idx < alias_pool->size; ++idx) {
+		if (alias_pool->aliases[idx] == alias) {
+			clear_bit(idx, alias_pool->use_mask);
+			spin_unlock(&alias_pool->lock);
+			return;
+		}
+	}
+
+	spin_unlock(&alias_pool->lock);
+}
+
 static struct i2c_atr_alias_pair *
-i2c_atr_find_mapping_by_client(const struct list_head *list,
-			       const struct i2c_client *client)
+i2c_atr_find_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr)
 {
 	struct i2c_atr_alias_pair *c2a;
 
-	list_for_each_entry(c2a, list, node) {
-		if (c2a->client == client)
+	lockdep_assert_held(&chan->alias_pairs_lock);
+
+	list_for_each_entry(c2a, &chan->alias_pairs, node) {
+		if (c2a->addr == addr)
 			return c2a;
 	}
 
@@ -112,18 +257,107 @@ i2c_atr_find_mapping_by_client(const struct list_head *list,
 }
 
 static struct i2c_atr_alias_pair *
-i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr)
+i2c_atr_create_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr)
 {
+	struct i2c_atr *atr = chan->atr;
 	struct i2c_atr_alias_pair *c2a;
+	u16 alias;
+	int ret;
 
-	list_for_each_entry(c2a, list, node) {
-		if (c2a->client->addr == phys_addr)
-			return c2a;
+	lockdep_assert_held(&chan->alias_pairs_lock);
+
+	ret = i2c_atr_reserve_alias(chan->alias_pool);
+	if (ret < 0)
+		return NULL;
+
+	alias = ret;
+
+	c2a = i2c_atr_create_c2a(chan, alias, addr);
+	if (!c2a)
+		goto err_release_alias;
+
+	ret = atr->ops->attach_addr(atr, chan->chan_id, c2a->addr, c2a->alias);
+	if (ret) {
+		dev_err(atr->dev, "failed to attach 0x%02x on channel %d: err %d\n",
+			addr, chan->chan_id, ret);
+		goto err_del_c2a;
 	}
 
+	return c2a;
+
+err_del_c2a:
+	i2c_atr_destroy_c2a(&c2a);
+err_release_alias:
+	i2c_atr_release_alias(chan->alias_pool, alias);
 	return NULL;
 }
 
+static struct i2c_atr_alias_pair *
+i2c_atr_replace_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr)
+{
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_atr_alias_pair *c2a;
+	struct list_head *alias_pairs;
+	bool found = false;
+	u16 alias;
+	int ret;
+
+	lockdep_assert_held(&chan->alias_pairs_lock);
+
+	alias_pairs = &chan->alias_pairs;
+
+	if (unlikely(list_empty(alias_pairs)))
+		return NULL;
+
+	list_for_each_entry_reverse(c2a, alias_pairs, node) {
+		if (!c2a->fixed) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found)
+		return NULL;
+
+	atr->ops->detach_addr(atr, chan->chan_id, c2a->addr);
+	c2a->addr = addr;
+
+	list_move(&c2a->node, alias_pairs);
+
+	alias = c2a->alias;
+
+	ret = atr->ops->attach_addr(atr, chan->chan_id, c2a->addr, c2a->alias);
+	if (ret) {
+		dev_err(atr->dev, "failed to attach 0x%02x on channel %d: err %d\n",
+			addr, chan->chan_id, ret);
+		i2c_atr_destroy_c2a(&c2a);
+		i2c_atr_release_alias(chan->alias_pool, alias);
+		return NULL;
+	}
+
+	return c2a;
+}
+
+static struct i2c_atr_alias_pair *
+i2c_atr_get_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr)
+{
+	struct i2c_atr *atr = chan->atr;
+	struct i2c_atr_alias_pair *c2a;
+
+	c2a = i2c_atr_find_mapping_by_addr(chan, addr);
+	if (c2a)
+		return c2a;
+
+	if (atr->flags & I2C_ATR_F_STATIC)
+		return NULL;
+
+	c2a = i2c_atr_create_mapping_by_addr(chan, addr);
+	if (c2a)
+		return c2a;
+
+	return i2c_atr_replace_mapping_by_addr(chan, addr);
+}
+
 /*
  * Replace all message addresses with their aliases, saving the original
  * addresses.
@@ -136,7 +370,7 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
 {
 	struct i2c_atr *atr = chan->atr;
 	static struct i2c_atr_alias_pair *c2a;
-	int i;
+	int i, ret = 0;
 
 	/* Ensure we have enough room to save the original addresses */
 	if (unlikely(chan->orig_addrs_size < num)) {
@@ -152,25 +386,36 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
 		chan->orig_addrs_size = num;
 	}
 
+	mutex_lock(&chan->alias_pairs_lock);
+
 	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);
+		c2a = i2c_atr_get_mapping_by_addr(chan, msgs[i].addr);
+
 		if (!c2a) {
+			if (atr->flags & I2C_ATR_F_PASSTHROUGH)
+				continue;
+
 			dev_err(atr->dev, "client 0x%02x not mapped!\n",
 				msgs[i].addr);
 
 			while (i--)
 				msgs[i].addr = chan->orig_addrs[i];
 
-			return -ENXIO;
+			ret = -ENXIO;
+			goto out_unlock;
 		}
 
+		// Prevent c2a from being overwritten by another client in this transaction
+		c2a->fixed = true;
+
 		msgs[i].addr = c2a->alias;
 	}
 
-	return 0;
+out_unlock:
+	mutex_unlock(&chan->alias_pairs_lock);
+	return ret;
 }
 
 /*
@@ -183,10 +428,24 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
 static void i2c_atr_unmap_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs,
 			       int num)
 {
+	struct i2c_atr_alias_pair *c2a;
 	int i;
 
 	for (i = 0; i < num; i++)
 		msgs[i].addr = chan->orig_addrs[i];
+
+	mutex_lock(&chan->alias_pairs_lock);
+
+	if (unlikely(list_empty(&chan->alias_pairs)))
+		goto out_unlock;
+
+	// unfix c2a entries so that subsequent transfers can reuse their aliases
+	list_for_each_entry(c2a, &chan->alias_pairs, node) {
+		c2a->fixed = false;
+	}
+
+out_unlock:
+	mutex_unlock(&chan->alias_pairs_lock);
 }
 
 static int i2c_atr_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
@@ -224,14 +483,23 @@ static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr,
 	struct i2c_atr *atr = chan->atr;
 	struct i2c_adapter *parent = atr->parent;
 	struct i2c_atr_alias_pair *c2a;
+	u16 alias;
 
-	c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr);
-	if (!c2a) {
+	mutex_lock(&chan->alias_pairs_lock);
+
+	c2a = i2c_atr_get_mapping_by_addr(chan, addr);
+
+	if (!c2a && !(atr->flags & I2C_ATR_F_PASSTHROUGH)) {
 		dev_err(atr->dev, "client 0x%02x not mapped!\n", addr);
+		mutex_unlock(&chan->alias_pairs_lock);
 		return -ENXIO;
 	}
 
-	return i2c_smbus_xfer(parent, c2a->alias, flags, read_write, command,
+	alias = c2a ? c2a->alias : addr;
+
+	mutex_unlock(&chan->alias_pairs_lock);
+
+	return i2c_smbus_xfer(parent, alias, flags, read_write, command,
 			      size, data);
 }
 
@@ -273,112 +541,60 @@ static const struct i2c_lock_operations i2c_atr_lock_ops = {
 	.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)
+static int i2c_atr_attach_addr(struct i2c_adapter *adapter,
+			       u16 addr)
 {
 	struct i2c_atr_chan *chan = adapter->algo_data;
 	struct i2c_atr *atr = chan->atr;
 	struct i2c_atr_alias_pair *c2a;
-	u16 alias;
-	int ret;
+	int ret = 0;
 
-	ret = i2c_atr_reserve_alias(atr);
-	if (ret < 0)
-		return ret;
+	mutex_lock(&chan->alias_pairs_lock);
 
-	alias = ret;
+	c2a = i2c_atr_create_mapping_by_addr(chan, addr);
+	if (!c2a && !(atr->flags & I2C_ATR_F_STATIC))
+		c2a = i2c_atr_replace_mapping_by_addr(chan, addr);
 
-	c2a = kzalloc(sizeof(*c2a), GFP_KERNEL);
 	if (!c2a) {
-		ret = -ENOMEM;
-		goto err_release_alias;
+		dev_err(atr->dev, "failed to find a free alias\n");
+		ret = -EBUSY;
+		goto out_unlock;
 	}
 
-	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);
+	dev_dbg(atr->dev, "chan%u: using alias 0x%02x for addr 0x%02x\n",
+		chan->chan_id, c2a->alias, addr);
 
+out_unlock:
+	mutex_unlock(&chan->alias_pairs_lock);
 	return ret;
 }
 
-static void i2c_atr_detach_client(struct i2c_adapter *adapter,
-				  const struct i2c_client *client)
+static void i2c_atr_detach_addr(struct i2c_adapter *adapter,
+				u16 addr)
 {
 	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);
+	atr->ops->detach_addr(atr, chan->chan_id, addr);
+
+	mutex_lock(&chan->alias_pairs_lock);
 
-	c2a = i2c_atr_find_mapping_by_client(&chan->alias_list, client);
+	c2a = i2c_atr_find_mapping_by_addr(chan, addr);
 	if (!c2a) {
-		 /* This should never happen */
-		dev_warn(atr->dev, "Unable to find address mapping\n");
+		mutex_unlock(&chan->alias_pairs_lock);
 		return;
 	}
 
-	i2c_atr_release_alias(atr, c2a->alias);
+	i2c_atr_release_alias(chan->alias_pool, 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);
+		"chan%u: detached alias 0x%02x from addr 0x%02x\n",
+		chan->chan_id, c2a->alias, addr);
 
-	list_del(&c2a->node);
-	kfree(c2a);
+	i2c_atr_destroy_c2a(&c2a);
+
+	mutex_unlock(&chan->alias_pairs_lock);
 }
 
 static int i2c_atr_bus_notifier_call(struct notifier_block *nb,
@@ -405,7 +621,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb,
 
 	switch (event) {
 	case BUS_NOTIFY_ADD_DEVICE:
-		ret = i2c_atr_attach_client(client->adapter, client);
+		ret = i2c_atr_attach_addr(client->adapter, client->addr);
 		if (ret)
 			dev_err(atr->dev,
 				"Failed to attach remote client '%s': %d\n",
@@ -413,7 +629,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb,
 		break;
 
 	case BUS_NOTIFY_REMOVED_DEVICE:
-		i2c_atr_detach_client(client->adapter, client);
+		i2c_atr_detach_addr(client->adapter, client->addr);
 		break;
 
 	default:
@@ -425,29 +641,43 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb,
 
 static int i2c_atr_parse_alias_pool(struct i2c_atr *atr)
 {
+	struct i2c_atr_alias_pool *alias_pool;
 	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);
+	if (!fwnode_property_present(dev_fwnode(dev), "i2c-alias-pool")) {
+		num_aliases = 0;
+	} else {
+		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;
+	}
+
+	alias_pool = i2c_atr_alloc_alias_pool(num_aliases, true);
+	if (IS_ERR(alias_pool)) {
+		ret = PTR_ERR(alias_pool);
+		dev_err(dev, "Failed to allocate alias pool, err %d\n", ret);
 		return ret;
 	}
 
-	num_aliases = ret;
+	atr->alias_pool = alias_pool;
 
-	if (!num_aliases)
+	if (!alias_pool->size)
 		return 0;
 
 	aliases32 = kcalloc(num_aliases, sizeof(*aliases32), GFP_KERNEL);
-	if (!aliases32)
-		return -ENOMEM;
+	if (!aliases32) {
+		ret = -ENOMEM;
+		goto err_free_alias_pool;
+	}
 
 	ret = fwnode_property_read_u32_array(dev_fwnode(dev), "i2c-alias-pool",
 					     aliases32, num_aliases);
@@ -457,48 +687,33 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr)
 		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];
+			alias_pool->aliases[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;
+		goto err_free_aliases32;
 	}
 
 	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);
+	dev_dbg(dev, "i2c-alias-pool has %zu aliases\n", alias_pool->size);
 
 	return 0;
 
-err_free_aliases16:
-	kfree(aliases16);
 err_free_aliases32:
 	kfree(aliases32);
+err_free_alias_pool:
+	i2c_atr_free_alias_pool(alias_pool);
 	return ret;
 }
 
 struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
-			    const struct i2c_atr_ops *ops, int max_adapters)
+			    const struct i2c_atr_ops *ops, int max_adapters,
+			    u32 flags)
 {
 	struct i2c_atr *atr;
 	int ret;
@@ -506,20 +721,21 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
 	if (max_adapters > ATR_MAX_ADAPTERS)
 		return ERR_PTR(-EINVAL);
 
-	if (!ops || !ops->attach_client || !ops->detach_client)
+	if (!ops || !ops->attach_addr || !ops->detach_addr)
 		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);
+	lockdep_register_key(&atr->lock_key);
+	mutex_init_with_key(&atr->lock, &atr->lock_key);
 
 	atr->parent = parent;
 	atr->dev = dev;
 	atr->ops = ops;
 	atr->max_adapters = max_adapters;
+	atr->flags = flags;
 
 	if (parent->algo->master_xfer)
 		atr->algo.master_xfer = i2c_atr_master_xfer;
@@ -534,15 +750,15 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev,
 	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;
+		goto err_free_alias_pool;
 
 	return atr;
 
-err_free_aliases:
-	bitmap_free(atr->alias_use_mask);
-	kfree(atr->aliases);
+err_free_alias_pool:
+	i2c_atr_free_alias_pool(atr->alias_pool);
 err_destroy_mutex:
 	mutex_destroy(&atr->lock);
+	lockdep_unregister_key(&atr->lock_key);
 	kfree(atr);
 
 	return ERR_PTR(ret);
@@ -557,22 +773,22 @@ void i2c_atr_delete(struct i2c_atr *atr)
 		WARN_ON(atr->adapter[i]);
 
 	bus_unregister_notifier(&i2c_bus_type, &atr->i2c_nb);
-	bitmap_free(atr->alias_use_mask);
-	kfree(atr->aliases);
+	i2c_atr_free_alias_pool(atr->alias_pool);
 	mutex_destroy(&atr->lock);
+	lockdep_unregister_key(&atr->lock_key);
 	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)
+int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc)
 {
+	struct fwnode_handle *bus_handle = desc->bus_handle;
 	struct i2c_adapter *parent = atr->parent;
+	char symlink_name[ATR_MAX_SYMLINK_LEN];
 	struct device *dev = atr->dev;
+	u32 chan_id = desc->chan_id;
 	struct i2c_atr_chan *chan;
-	char symlink_name[ATR_MAX_SYMLINK_LEN];
-	int ret;
+	int ret, idx;
 
 	if (chan_id >= atr->max_adapters) {
 		dev_err(dev, "No room for more i2c-atr adapters\n");
@@ -588,20 +804,23 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
 	if (!chan)
 		return -ENOMEM;
 
-	if (!adapter_parent)
-		adapter_parent = dev;
+	if (!desc->parent)
+		desc->parent = dev;
 
 	chan->atr = atr;
 	chan->chan_id = chan_id;
-	INIT_LIST_HEAD(&chan->alias_list);
-	mutex_init(&chan->orig_addrs_lock);
+	INIT_LIST_HEAD(&chan->alias_pairs);
+	lockdep_register_key(&chan->alias_pairs_lock_key);
+	lockdep_register_key(&chan->orig_addrs_lock_key);
+	mutex_init_with_key(&chan->alias_pairs_lock, &chan->alias_pairs_lock_key);
+	mutex_init_with_key(&chan->orig_addrs_lock, &chan->orig_addrs_lock_key);
 
 	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.dev.parent = desc->parent;
 	chan->adap.retries = parent->retries;
 	chan->adap.timeout = parent->timeout;
 	chan->adap.quirks = parent->quirks;
@@ -628,13 +847,26 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
 		fwnode_handle_put(atr_node);
 	}
 
+	if (desc->num_aliases > 0) {
+		chan->alias_pool = i2c_atr_alloc_alias_pool(desc->num_aliases, false);
+		if (IS_ERR(chan->alias_pool)) {
+			ret = PTR_ERR(chan->alias_pool);
+			goto err_fwnode_put;
+		}
+
+		for (idx = 0; idx < desc->num_aliases; idx++)
+			chan->alias_pool->aliases[idx] = desc->aliases[idx];
+	} else {
+		chan->alias_pool = atr->alias_pool;
+	}
+
 	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;
+		goto err_free_alias_pool;
 	}
 
 	snprintf(symlink_name, sizeof(symlink_name), "channel-%u",
@@ -651,9 +883,15 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id,
 
 	return 0;
 
+err_free_alias_pool:
+	if (!chan->alias_pool->shared)
+		i2c_atr_free_alias_pool(chan->alias_pool);
 err_fwnode_put:
 	fwnode_handle_put(dev_fwnode(&chan->adap.dev));
 	mutex_destroy(&chan->orig_addrs_lock);
+	mutex_destroy(&chan->alias_pairs_lock);
+	lockdep_unregister_key(&chan->orig_addrs_lock_key);
+	lockdep_unregister_key(&chan->alias_pairs_lock_key);
 	kfree(chan);
 	return ret;
 }
@@ -683,10 +921,16 @@ void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id)
 
 	i2c_del_adapter(adap);
 
+	if (!chan->alias_pool->shared)
+		i2c_atr_free_alias_pool(chan->alias_pool);
+
 	atr->adapter[chan_id] = NULL;
 
 	fwnode_handle_put(fwnode);
 	mutex_destroy(&chan->orig_addrs_lock);
+	mutex_destroy(&chan->alias_pairs_lock);
+	lockdep_unregister_key(&chan->orig_addrs_lock_key);
+	lockdep_unregister_key(&chan->alias_pairs_lock_key);
 	kfree(chan->orig_addrs);
 	kfree(chan);
 }