| From: Sven Eckelmann <seckelmann@datto.com> |
| Date: Wed, 28 Nov 2018 16:16:27 +0100 |
| Subject: ath10k: adjust tx power reduction for US regulatory domain |
| |
| FCC allows maximum antenna gain of 6 dBi. 15.247(b)(4): |
| |
| > (4) The conducted output power limit |
| > specified in paragraph (b) of this section |
| > is based on the use of antennas |
| > with directional gains that do not exceed |
| > 6 dBi. Except as shown in paragraph |
| > (c) of this section, if transmitting |
| > antennas of directional gain greater |
| > than 6 dBi are used, the conducted |
| > output power from the intentional radiator |
| > shall be reduced below the stated |
| > values in paragraphs (b)(1), (b)(2), |
| > and (b)(3) of this section, as appropriate, |
| > by the amount in dB that the |
| > directional gain of the antenna exceeds |
| > 6 dBi. |
| |
| https://www.gpo.gov/fdsys/pkg/CFR-2013-title47-vol1/pdf/CFR-2013-title47-vol1-sec15-247.pdf |
| |
| Signed-off-by: Sven Eckelmann <seckelmann@datto.com> |
| |
| Forwarded: no |
| |
| --- a/drivers/net/wireless/ath/ath10k/mac.c |
| +++ b/drivers/net/wireless/ath/ath10k/mac.c |
| @@ -1017,6 +1017,40 @@ static inline int ath10k_vdev_setup_sync |
| return ar->last_wmi_vdev_start_status; |
| } |
| |
| +static u32 ath10k_get_max_antenna_gain(struct ath10k *ar, |
| + u32 ch_max_antenna_gain) |
| +{ |
| + u32 max_antenna_gain; |
| + |
| + if (ar->dfs_detector && ar->dfs_detector->region == NL80211_DFS_FCC) { |
| + /* FCC allows maximum antenna gain of 6 dBi. 15.247(b)(4): |
| + * |
| + * > (4) The conducted output power limit |
| + * > specified in paragraph (b) of this section |
| + * > is based on the use of antennas |
| + * > with directional gains that do not exceed |
| + * > 6 dBi. Except as shown in paragraph |
| + * > (c) of this section, if transmitting |
| + * > antennas of directional gain greater |
| + * > than 6 dBi are used, the conducted |
| + * > output power from the intentional radiator |
| + * > shall be reduced below the stated |
| + * > values in paragraphs (b)(1), (b)(2), |
| + * > and (b)(3) of this section, as appropriate, |
| + * > by the amount in dB that the |
| + * > directional gain of the antenna exceeds |
| + * > 6 dBi. |
| + * |
| + * https://www.gpo.gov/fdsys/pkg/CFR-2013-title47-vol1/pdf/CFR-2013-title47-vol1-sec15-247.pdf |
| + */ |
| + max_antenna_gain = 6; |
| + } else { |
| + max_antenna_gain = 0; |
| + } |
| + |
| + return max(ch_max_antenna_gain, max_antenna_gain); |
| +} |
| + |
| static int ath10k_monitor_vdev_start(struct ath10k *ar, int vdev_id) |
| { |
| struct cfg80211_chan_def *chandef = NULL; |
| @@ -1049,7 +1083,8 @@ static int ath10k_monitor_vdev_start(str |
| arg.channel.min_power = 0; |
| arg.channel.max_power = channel->max_power * 2; |
| arg.channel.max_reg_power = channel->max_reg_power * 2; |
| - arg.channel.max_antenna_gain = channel->max_antenna_gain; |
| + arg.channel.max_antenna_gain = ath10k_get_max_antenna_gain(ar, |
| + channel->max_antenna_gain); |
| |
| reinit_completion(&ar->vdev_setup_done); |
| reinit_completion(&ar->vdev_delete_done); |
| @@ -1495,7 +1530,8 @@ static int ath10k_vdev_start_restart(str |
| arg.channel.min_power = 0; |
| arg.channel.max_power = chandef->chan->max_power * 2; |
| arg.channel.max_reg_power = chandef->chan->max_reg_power * 2; |
| - arg.channel.max_antenna_gain = chandef->chan->max_antenna_gain; |
| + arg.channel.max_antenna_gain = ath10k_get_max_antenna_gain(ar, |
| + chandef->chan->max_antenna_gain); |
| |
| if (arvif->vdev_type == WMI_VDEV_TYPE_AP) { |
| arg.ssid = arvif->u.ap.ssid; |
| @@ -3266,7 +3302,8 @@ static int ath10k_update_channel_list(st |
| ch->min_power = 0; |
| ch->max_power = channel->max_power * 2; |
| ch->max_reg_power = channel->max_reg_power * 2; |
| - ch->max_antenna_gain = channel->max_antenna_gain; |
| + ch->max_antenna_gain = ath10k_get_max_antenna_gain(ar, |
| + channel->max_antenna_gain); |
| ch->reg_class_id = 0; /* FIXME */ |
| |
| /* FIXME: why use only legacy modes, why not any |