Re: [RFCv3 bluetooth-next 4/6] mac802154: change max_frame_retries behaviour

[Stefan Schmidt <stefan@osg.samsung.com>]

Hello.

On 30/07/15 10:55, Alexander Aring wrote:
> This patch changes the default min value of max_frame_retries to 0 and
> changes the max_frame_retries default value to 3 which is also 802.15.4
> default.
You mean min_frame_retries to 0 here?


> We don't use max_frame_retries "-1" as indicator for no-aret mode
> anymore, instead we checking on the ack request bit inside the 802.15.4
> frame control field.
>
> Signed-off-by: Alexander Aring <alex.aring@gmail.com>
> ---
>   net/mac802154/iface.c | 3 +--
>   net/mac802154/main.c  | 9 +++------
>   2 files changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c
> index 416de90..8837c5a 100644
> --- a/net/mac802154/iface.c
> +++ b/net/mac802154/iface.c
> @@ -483,8 +483,7 @@ ieee802154_setup_sdata(struct ieee802154_sub_if_data *sdata,
>   	wpan_dev->min_be = 3;
>   	wpan_dev->max_be = 5;
>   	wpan_dev->csma_retries = 4;
> -	/* for compatibility, actual default is 3 */
> -	wpan_dev->frame_retries = -1;
> +	wpan_dev->frame_retries = 3;
>   
>   	wpan_dev->pan_id = cpu_to_le16(IEEE802154_PANID_BROADCAST);
>   	wpan_dev->short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
> diff --git a/net/mac802154/main.c b/net/mac802154/main.c
> index 91f1208..6e1764b 100644
> --- a/net/mac802154/main.c
> +++ b/net/mac802154/main.c
> @@ -109,7 +109,7 @@ ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
>   	phy->supported.max_minbe = 8;
>   	phy->supported.min_maxbe = 3;
>   	phy->supported.max_maxbe = 8;
> -	phy->supported.min_frame_retries = -1;
> +	phy->supported.min_frame_retries = 0;
>   	phy->supported.max_frame_retries = 7;

Maybe also set it to 3 here if we want to have this as default and 
letting it to userspace to set it to another value if needed?

>   	phy->supported.max_csma_backoffs = 5;
>   	phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
> @@ -175,11 +175,8 @@ int ieee802154_register_hw(struct ieee802154_hw *hw)
>   	}
>   
>   	if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
> -		/* TODO should be 3, but our default value is -1 which means
> -		 * no ARET handling.
> -		 */
> -		local->phy->supported.min_frame_retries = -1;
> -		local->phy->supported.max_frame_retries = -1;
> +		local->phy->supported.min_frame_retries = 3;
> +		local->phy->supported.max_frame_retries = 3;

This confuses me. During alloc_hw we set min to 0 which makes sense for 
me but afterwards we set both, min and max, to 3? Should it not only be 
max to three here? Am I missing something?

regards
Stefan Schmidt