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| author | Jean Delvare <khali@linux-fr.org> | 2006-09-30 17:18:59 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-30 10:58:47 -0700 |
| commit | 77ed74da26f50fa28471571ee7a2251b77526d84 (patch) | |
| tree | 5db5671bb6f69613103ded68027b1d7e8677c87e /drivers | |
| parent | 5ffd1a6aaacc25be8cd0770a51ec6d46add3a276 (diff) | |
| download | lwn-77ed74da26f50fa28471571ee7a2251b77526d84.tar.gz lwn-77ed74da26f50fa28471571ee7a2251b77526d84.zip | |
[PATCH] i2c: Prevent deadlock on i2c client registration
Delay the call to adapter->client_register() until after we are
certain that the client registration is a success. At this point the
client is fully initialized and we no longer hold the adapter->clist
mutex, so this should prevent the deadlocks if the client_register()
callback needs to take that mutex too, as is the case for the bttv
driver.
This fixes bug #7234.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/i2c/i2c-core.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 01233f0f7771..7ca81f42d14b 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -420,14 +420,6 @@ int i2c_attach_client(struct i2c_client *client) } list_add_tail(&client->list,&adapter->clients); - if (adapter->client_register) { - if (adapter->client_register(client)) { - dev_dbg(&adapter->dev, "client_register " - "failed for client [%s] at 0x%02x\n", - client->name, client->addr); - } - } - client->usage_count = 0; client->dev.parent = &client->adapter->dev; @@ -445,10 +437,17 @@ int i2c_attach_client(struct i2c_client *client) res = device_create_file(&client->dev, &dev_attr_client_name); if (res) goto out_unregister; - -out_unlock: mutex_unlock(&adapter->clist_lock); - return res; + + if (adapter->client_register) { + if (adapter->client_register(client)) { + dev_dbg(&adapter->dev, "client_register " + "failed for client [%s] at 0x%02x\n", + client->name, client->addr); + } + } + + return 0; out_unregister: init_completion(&client->released); /* Needed? */ @@ -458,7 +457,9 @@ out_list: list_del(&client->list); dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x " "(%d)\n", client->name, client->addr, res); - goto out_unlock; +out_unlock: + mutex_unlock(&adapter->clist_lock); + return res; } |