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 <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index c8bbd67..824f12c 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -709,13 +709,6 @@
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 @@
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 @@
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);