From 86ec5ec872566dda74848e09904bb5380cab962e Mon Sep 17 00:00:00 2001 From: David Brownell Date: Sun, 27 Jan 2008 18:14:51 +0100 Subject: [PATCH] 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: David Brownell Signed-off-by: Jean Delvare --- drivers/i2c/i2c-core.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index c8bbd672226b..824f12c798d6 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -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);