Re: [PATCH v3 1/4] HID: wiimote: turn on the LEDs indicating the controller id

On Fri Jul 31, 2026 at 6:02 AM -03, David Rheinsberg wrote:
>> -	hid_info(hdev, "New device registered\n");
>> +	player_id = ida_alloc_min(&wiimote_ida, 1, GFP_KERNEL);
>> +	if (player_id < 1) {
>> +		hid_err(hdev, "cannot allocate controller id\n");
>> +		ret = player_id;
>> +		goto err_free;
>> +	}
>> +
>> +	wdata->player_id = player_id;
>> +
>> +	hid_info(hdev, "New device registered (Wiimote %d)\n", player_id);
>
> `wiimote_create()` should initialize `wdata->player_id` to -1, so `ida_free()` is a no-op in the `err_free` path. Right now it is implicitly initialized to 0, and thus ida_free() will warn about an unallocated ID.
>
> Also: Why not just use IDs starting from 0?

I chose to start from 1 to avoid "id 0 = player 1".

Wouldn't setting an u8 to -1 result into 255 ? If so,
this would not be a no-op. Also, comparing player_id < 0 would never be
true. If the IDA starts from 0, there is no usable "empty value" in a u8
when deciding if I should call ida_free.
If I let "failure" to be 0, I can just use this in destroy:

if (wdata->player_id)
	ida_free(&wiimote_ida, wdata->player_id);


Thanks,
Rafael