err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
        if (err != ARRAY_SIZE(msgs)) {
-               v4l2_err(sd, "%s: reading register 0x%x from 0x%x failed\n",
-                               __func__, reg, client->addr);
+               v4l2_err(sd, "%s: reading register 0x%x from 0x%x failed: %d\n",
+                               __func__, reg, client->addr, err);
        }
 }
 
 
        err = i2c_transfer(client->adapter, &msg, 1);
        if (err != 1) {
-               v4l2_err(sd, "%s: writing register 0x%x from 0x%x failed\n",
-                               __func__, reg, client->addr);
+               v4l2_err(sd, "%s: writing register 0x%x from 0x%x failed: %d\n",
+                               __func__, reg, client->addr, err);
                return;
        }