i2c: Allow i2c_add_numbered_adapter() to assign a bus id

Currently, if an i2c bus driver supports both static and dynamic bus
ids, it needs to choose between calling i2c_add_numbered_adapter() and
i2c_add_adapter().  This patch makes i2c_add_numbered_adapter()
redirect to i2c_add_adapter() if the requested bus id is -1.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 9a58994ff7ea..131079a3e292 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -925,6 +925,9 @@ EXPORT_SYMBOL(i2c_add_adapter);
  * or otherwise built in to the system's mainboard, and where i2c_board_info
  * is used to properly configure I2C devices.
  *
+ * If the requested bus number is set to -1, then this function will behave
+ * identically to i2c_add_adapter, and will dynamically assign a bus number.
+ *
  * If no devices have pre-been declared for this bus, then be sure to
  * register the adapter before any dynamically allocated ones.  Otherwise
  * the required bus ID may not be available.
@@ -940,6 +943,8 @@ int i2c_add_numbered_adapter(struct i2c_adapter *adap)
         int     id;
         int     status;
 
+        if (adap->nr == -1) /* -1 means dynamically assign bus id */
+                return i2c_add_adapter(adap);
         if (adap->nr & ~MAX_ID_MASK)
                 return -EINVAL;