[PATCH] i2c: Rework client usage count, 3 of 3
Do not limit the usage count of i2c clients to 1. In other words,
change the client usage count behavior from the old I2C_CLIENT_ALLOW_USE
to the old I2C_CLIENT_ALLOW_MULTIPLE_USE. The rationale is that no
driver actually needs the limiting behavior, and the unlimiting
behavior is slightly easier to implement.
Update the documentation to reflect this change.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/i2c/porting-clients b/Documentation/i2c/porting-clients
index 64c610b..6b07f23 100644
--- a/Documentation/i2c/porting-clients
+++ b/Documentation/i2c/porting-clients
@@ -92,6 +92,7 @@
Drop client->id.
Drop any 24RF08 corruption prevention you find, as this is now done
at the i2c-core level, and doing it twice voids it.
+ Don't add I2C_CLIENT_ALLOW_USE to client->flags, it's the default now.
* [Init] Limits must not be set by the driver (can be done later in
user-space). Chip should not be reset default (although a module
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index d16b499..a1c5dff 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -497,14 +497,9 @@
if (ret)
return ret;
- if (client->usage_count > 0)
- goto busy;
client->usage_count++;
return 0;
- busy:
- i2c_dec_use_client(client);
- return -EBUSY;
}
int i2c_release_client(struct i2c_client *client)
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 8b4d469..85c517a 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -307,9 +307,7 @@
extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
to make sure that client-struct is valid and that it is okay to access
the i2c-client.
- returns -EACCES if client doesn't allow use (default)
- returns -EBUSY if client doesn't allow multiple use (default) and
- usage_count >0 */
+ returns -ENODEV if client has gone in the meantime */
extern int i2c_use_client(struct i2c_client *);
extern int i2c_release_client(struct i2c_client *);
