Commit 86ec5ec8 authored by David Brownell's avatar David Brownell Committed by Jean Delvare
Browse files

i2c-remove-redundant-i2c_client-list.patch 



This goes on top of the patch removing most i2c_adapter.clients usage,
updating i2c_attach_client:

 - Don't call device_register() while holding clist_lock.  This
   removes a self-deadlock when on the i2c_driver.probe() path,
   for drivers that need to attach new devices (e.g. dummies).

 - Remove a redundant address check.  The driver model core does
   this as a consequence of guaranteeing unique names.

 - Move the "device registered" diagnostic so that it never lies;
   previously, on error paths it would falsely report success.

Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 961f80f9

drivers/i2c/i2c-core.c

+8 −14
Original line number Diff line number Diff line
@@ -709,13 +709,6 @@ int i2c_attach_client(struct i2c_client *client) 
	struct i2c_adapter *adapter = client->adapter;

	int res = 0;



	mutex_lock(&adapter->clist_lock);

	if (i2c_check_addr(client->adapter, client->addr)) {

		res = -EBUSY;

		goto out_unlock;

	}

	list_add_tail(&client->list,&adapter->clients);



	client->dev.parent = &client->adapter->dev;

	client->dev.bus = &i2c_bus_type;
@@ -730,13 +723,17 @@ int i2c_attach_client(struct i2c_client *client) 


	snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id),

		"%d-%04x", i2c_adapter_id(adapter), client->addr);

	dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n",

		client->name, client->dev.bus_id);

	res = device_register(&client->dev);

	if (res)

		goto out_list;

		goto out_err;



	mutex_lock(&adapter->clist_lock);

	list_add_tail(&client->list, &adapter->clients);

	mutex_unlock(&adapter->clist_lock);



	dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n",

		client->name, client->dev.bus_id);



	if (adapter->client_register)  {

		if (adapter->client_register(client)) {

			dev_dbg(&adapter->dev, "client_register "
@@ -747,12 +744,9 @@ int i2c_attach_client(struct i2c_client *client) 


	return 0;



out_list:

	list_del(&client->list);

out_err:

	dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x "

		"(%d)\n", client->name, client->addr, res);

out_unlock:

	mutex_unlock(&adapter->clist_lock);

	return res;

}

EXPORT_SYMBOL(i2c_attach_client);

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