return -EINVAL;
 
        if (strncmp(adapter->name, "mac-io", 6))
-               return 0; /* ignored */
+               return -EINVAL; /* ignored */
 
        memset(&info, 0, sizeof(struct i2c_board_info));
        strlcpy(info.type, "keywest", I2C_NAME_SIZE);
        .driver = {
                .name = "PMac Keywest Audio",
        },
-       .attach_adapter = keywest_attach_adapter,
        .probe = keywest_probe,
        .remove = keywest_remove,
        .id_table = keywest_i2c_id,
 /* exported */
 int snd_pmac_keywest_init(struct pmac_keywest *i2c)
 {
-       int err;
+       struct i2c_adapter *adap;
+       int err, i = 0;
 
        if (keywest_ctx)
                return -EBUSY;
 
+       adap = i2c_get_adapter(0);
+       if (!adap)
+               return -EPROBE_DEFER;
+
        keywest_ctx = i2c;
 
        if ((err = i2c_add_driver(&keywest_driver))) {
                snd_printk(KERN_ERR "cannot register keywest i2c driver\n");
+               i2c_put_adapter(adap);
                return err;
        }
-       return 0;
+
+       /* We assume Macs have consecutive I2C bus numbers starting at 0 */
+       while (adap) {
+               err = keywest_attach_adapter(adap);
+               if (!err)
+                       return 0;
+               i2c_put_adapter(adap);
+               adap = i2c_get_adapter(++i);
+       }
+
+       return -ENODEV;
 }