[153/272] i2c: Unregister dummy devices last on adapter removal

Greg KH
2011-02-16T01:25:38Z

From: Jean Delvare <khali@linux-fr.org>

commit 5219bf884b6e2b54e734ca1799b6f0014bb2b4b7 upstream.

Remove real devices first and dummy devices last. This gives device
driver which instantiated dummy devices themselves a chance to clean
them up before we do.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/i2c/i2c-core.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1021,6 +1021,14 @@ static int i2c_do_del_adapter(struct i2c
static int __unregister_client(struct device *dev, void *dummy)
{
struct i2c_client *client = i2c_verify_client(dev);
+ if (client && strcmp(client->name, "dummy"))
+ i2c_unregister_device(client);
+ return 0;
+}
+
+static int __unregister_dummy(struct device *dev, void *dummy)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
if (client)
i2c_unregister_device(client);
return 0;
@@ -1075,8 +1083,12 @@ int i2c_del_adapter(struct i2c_adapter *
mutex_unlock(&adap->userspace_clients_lock);

/* Detach any active clients. This can't fail, thus we do not
- checking the returned value. */
+ * check the returned value. This is a two-pass process, because
+ * we can't remove the dummy devices during the first pass: they
+ * could have been instantiated by real devices wishing to clean
+ * them up properly, so we give them a chance to do that first. */
res = device_for_each_child(&adap->dev, NULL, __unregister_client);
+ res = device_for_each_child(&adap->dev, NULL, __unregister_dummy);

#ifdef CONFIG_I2C_COMPAT
class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,