Re: [PATCH v2] mac80211: Handle power constraint level advertised in 11d+h beacon

[Vasanthakumar Thiagarajan <vasanth@atheros.com>]

Vasanth Thiagarajan wrote:
> This patch uses power constraint level while determining the maximum
> transmit power, there by it makes sure that any power mitigation
> requirement for the channel in the current regulatory domain is met.
> 
> Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
> ---
>  net/mac80211/ieee80211_i.h |    4 ++++
>  net/mac80211/main.c        |   10 ++++++++--
>  net/mac80211/mlme.c        |    9 +++++++++
>  net/mac80211/spectmgmt.c   |   21 +++++++++++++++++++++
>  4 files changed, 42 insertions(+), 2 deletions(-)
> 
> diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
> index 7ec1333..941cd8d 100644
> --- a/net/mac80211/ieee80211_i.h
> +++ b/net/mac80211/ieee80211_i.h
> @@ -703,6 +703,7 @@ struct ieee80211_local {
>         struct timer_list dynamic_ps_timer;
> 
>         int user_power_level; /* in dBm */
> +       int power_constr_level; /* in dBm */
> 
>  #ifdef CONFIG_MAC80211_DEBUGFS
>         struct local_debugfsdentries {
> @@ -966,6 +967,9 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
>  void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
>                                        struct ieee80211_mgmt *mgmt,
>                                        size_t len);
> +void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
> +                                u16 capab_info, u8 *pwr_constr_elem,
> +                                u8 pwr_constr_elem_len);
> 
>  /* utility functions/constants */
>  extern void *mac80211_wiphy_privid; /* for wiphy privid */
> diff --git a/net/mac80211/main.c b/net/mac80211/main.c
> index b55b997..27f313c 100644
> --- a/net/mac80211/main.c
> +++ b/net/mac80211/main.c
> @@ -214,10 +214,16 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
>                 changed |= IEEE80211_CONF_CHANGE_CHANNEL;
>         }
> 
> -       if (!local->user_power_level)
> +       if (local->sw_scanning)
>                 power = chan->max_power;
>         else
> -               power = min(chan->max_power, local->user_power_level);
> +               power = local->power_constr_level ?
> +                       (chan->max_power - local->power_constr_level) :
> +                       chan->max_power;
> +
> +       if (local->user_power_level)
> +               power = min(power, local->user_power_level);
> +
>         if (local->hw.conf.power_level != power) {
>                 changed |= IEEE80211_CONF_CHANGE_POWER;
>                 local->hw.conf.power_level = power;
> diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
> index d108c12..f45fcb5 100644
> --- a/net/mac80211/mlme.c
> +++ b/net/mac80211/mlme.c
> @@ -910,6 +910,8 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
>         local->oper_channel_type = NL80211_CHAN_NO_HT;
>         config_changed |= IEEE80211_CONF_CHANGE_HT;
> 
> +       local->power_constr_level = 0;
> +
>         del_timer_sync(&local->dynamic_ps_timer);
>         cancel_work_sync(&local->dynamic_ps_enable_work);
> 
> @@ -1838,6 +1840,13 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
>                  * for the BSSID we are associated to */
>                 regulatory_hint_11d(local->hw.wiphy,
>                         elems.country_elem, elems.country_elem_len);
> +
> +               /* TODO: IBSS also needs this */
> +               if (elems.pwr_constr_elem)
> +                       ieee80211_handle_pwr_constr(sdata,
> +                               le16_to_cpu(mgmt->u.probe_resp.capab_info),
> +                               elems.pwr_constr_elem,
> +                               elems.pwr_constr_elem_len);
>         }
> 
>         ieee80211_bss_info_change_notify(sdata, changed);
> diff --git a/net/mac80211/spectmgmt.c b/net/mac80211/spectmgmt.c
> index f72bad6..b621e49 100644
> --- a/net/mac80211/spectmgmt.c
> +++ b/net/mac80211/spectmgmt.c
> @@ -84,3 +84,24 @@ void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
>                         mgmt->sa, mgmt->bssid,
>                         mgmt->u.action.u.measurement.dialog_token);
>  }
> +
> +void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
> +                                u16 capab_info, u8 *pwr_constr_elem,
> +                                u8 pwr_constr_elem_len)
> +{
> +       struct ieee80211_conf *conf = &sdata->local->hw.conf;
> +
> +       if (!(capab_info & WLAN_CAPABILITY_SPECTRUM_MGMT))
> +               return;
> +
> +       /* Power constraint IE length should be 1 octet */
> +       if (pwr_constr_elem_len != 1)
> +               return;
> +
> +       if ((*pwr_constr_elem <= conf->channel->max_power) &&
> +           (*pwr_constr_elem != sdata->local->power_constr_level)) {
> +               sdata->local->power_constr_level = *pwr_constr_elem;
> +               ieee80211_hw_config(sdata->local, 0);
> +       }
> +}
> +
> --
> 1.5.5.1
> 

This patch will apply over johannes' 'remove user_power_level from driver API' patch.

Vasanth