Re: [PATCH 3/6] rfkill: document the rfkill struct locking (v2)

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

On Tuesday 22 July 2008, Henrique de Moraes Holschuh wrote:
> Reorder fields in struct rfkill and add comments to make it clear
> which fields are protected by rfkill->mutex.
> 
> 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>

> ---
>  include/linux/rfkill.h |    8 +++++---
>  1 files changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
> index c5f6e54..741d1a6 100644
> --- a/include/linux/rfkill.h
> +++ b/include/linux/rfkill.h
> @@ -68,7 +68,8 @@ enum rfkill_state {
>   * @user_claim_unsupported: Whether the hardware supports exclusive
>   *	RF-kill control by userspace. Set this before registering.
>   * @user_claim: Set when the switch is controlled exlusively by userspace.
> - * @mutex: Guards switch state transitions
> + * @mutex: Guards switch state transitions.  It serializes callbacks
> + *	and also protects the state.
>   * @data: Pointer to the RF button drivers private data which will be
>   *	passed along when toggling radio state.
>   * @toggle_radio(): Mandatory handler to control state of the radio.
> @@ -89,12 +90,13 @@ struct rfkill {
>  	const char *name;
>  	enum rfkill_type type;
>  
> -	enum rfkill_state state;
>  	bool user_claim_unsupported;
>  	bool user_claim;
>  
> +	/* the mutex serializes callbacks and also protects
> +	 * the state */
>  	struct mutex mutex;
> -
> +	enum rfkill_state state;
>  	void *data;
>  	int (*toggle_radio)(void *data, enum rfkill_state state);
>  	int (*get_state)(void *data, enum rfkill_state *state);