Re: [PATCH 2/2] rfkill: ignore errors from rfkill_toggle_radio in rfkill_add_switch

[Ivo van Doorn <ivdoorn@gmail.com>]

On Thursday 03 July 2008, Henrique de Moraes Holschuh wrote:
> rfkill_add_switch() calls rfkill_toggle_radio() to set the state of a
> recently registered rfkill class to the current global state [for that
> rfkill->type].
> 
> The rfkill_toggle_radio() call is going to error out if the hardware is
> RFKILL_STATE_HARD_BLOCKED, and the global state is RFKILL_STATE_UNBLOCKED.
> 
> That is a quite normal situation which I missed to account for.  As things
> stand, the error return from rfkill_toggle_radio ends up causing
> rfkill_register to bail out with an error (de-registering the new switch in
> the process), which is Not Nice.
> 
> Change rfkill_add_switch() to not return errors because of a failed call to
> rfkill_toggle_radio().  We can go back to returning errors again (if that's
> indeed the right thing to do) if we define the exact error codes the
> rfkill->toggle_radio callbacks are to return in each situation, so that we
> can ignore the right ones only.
> 
> Bug reported by "kionez <kionez@anche.no>".
> 
> Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
> Cc: Ivo van Doorn <IvDoorn@gmail.com>

Acked-by: Ivo van Doorn <IvDoorn@gmail.com>

> Cc: kionez <kionez@anche.no>
> ---
>  net/rfkill/rfkill.c |   10 ++++------
>  1 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c
> index aa7039d..7a560b7 100644
> --- a/net/rfkill/rfkill.c
> +++ b/net/rfkill/rfkill.c
> @@ -501,17 +501,15 @@ static struct class rfkill_class = {
>  
>  static int rfkill_add_switch(struct rfkill *rfkill)
>  {
> -	int error;
> -
>  	mutex_lock(&rfkill_mutex);
>  
> -	error = rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0);
> -	if (!error)
> -		list_add_tail(&rfkill->node, &rfkill_list);
> +	rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0);
> +
> +	list_add_tail(&rfkill->node, &rfkill_list);
>  
>  	mutex_unlock(&rfkill_mutex);
>  
> -	return error;
> +	return 0;
>  }
>  
>  static void rfkill_remove_switch(struct rfkill *rfkill)