brcm80211: smac: enable/disable radio on regulatory updates

Currently the radio disable state is only updated during initialization,
and it's only checked against the internal world domain. This is
unnecessary, as there are always valid channels against this domain.
Instead, check whether any channels are enabled in the regulatory
notifier and update the radio state accordingly.
Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/brcm80211/brcmsmac/channel.c

@@ -677,46 +677,6 @@ brcms_c_channel_min_txpower_limits_with_local_constraint(
 
 }
 
-/* Update the radio state (enable/disable) and tx power targets
- * based on a new set of channel/regulatory information
- */
-static void brcms_c_channels_commit(struct brcms_cm_info *wlc_cm)
-{
-	struct brcms_c_info *wlc = wlc_cm->wlc;
-	uint chan;
-
-	/* search for the existence of any valid channel */
-	for (chan = 0; chan < MAXCHANNEL; chan++) {
-		if (brcms_c_valid_channel20_db(wlc->cmi, chan))
-			break;
-	}
-	if (chan == MAXCHANNEL)
-		chan = INVCHANNEL;
-
-	/*
-	 * based on the channel search above, set or
-	 * clear WL_RADIO_COUNTRY_DISABLE.
-	 */
-	if (chan == INVCHANNEL) {
-		/*
-		 * country/locale with no valid channels, set
-		 * the radio disable bit
-		 */
-		mboolset(wlc->pub->radio_disabled, WL_RADIO_COUNTRY_DISABLE);
-		wiphy_err(wlc->wiphy, "wl%d: %s: no valid channel for \"%s\" "
-			  "nbands %d bandlocked %d\n", wlc->pub->unit,
-			  __func__, wlc_cm->world_regd->regdomain->alpha2,
-			  wlc->pub->_nbands, wlc->bandlocked);
-	} else if (mboolisset(wlc->pub->radio_disabled,
-			      WL_RADIO_COUNTRY_DISABLE)) {
-		/*
-		 * country/locale with valid channel, clear
-		 * the radio disable bit
-		 */
-		mboolclr(wlc->pub->radio_disabled, WL_RADIO_COUNTRY_DISABLE);
-	}
-}
-
 static int
 brcms_c_channels_init(struct brcms_cm_info *wlc_cm,
 		      const struct country_info *country)
@@ -762,7 +722,6 @@ brcms_c_channels_init(struct brcms_cm_info *wlc_cm,
 	}
 
 	brcms_c_quiet_channels_reset(wlc_cm);
-	brcms_c_channels_commit(wlc_cm);
 
 	return 0;
 }
@@ -1235,12 +1194,38 @@ static int brcms_reg_notifier(struct wiphy *wiphy,
 	struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
 	struct brcms_info *wl = hw->priv;
 	struct brcms_c_info *wlc = wl->wlc;
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_channel *ch;
+	int band, i;
+	bool ch_found = false;
 
 	brcms_reg_apply_radar_flags(wiphy);
 
 	if (request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
 		brcms_reg_apply_beaconing_flags(wiphy, request->initiator);
 
+	/* Disable radio if all channels disallowed by regulatory */
+	for (band = 0; !ch_found && band < IEEE80211_NUM_BANDS; band++) {
+		sband = wiphy->bands[band];
+		if (!sband)
+			continue;
+
+		for (i = 0; !ch_found && i < sband->n_channels; i++) {
+			ch = &sband->channels[i];
+
+			if (!(ch->flags & IEEE80211_CHAN_DISABLED))
+				ch_found = true;
+		}
+	}
+
+	if (ch_found) {
+		mboolclr(wlc->pub->radio_disabled, WL_RADIO_COUNTRY_DISABLE);
+	} else {
+		mboolset(wlc->pub->radio_disabled, WL_RADIO_COUNTRY_DISABLE);
+		wiphy_err(wlc->wiphy, "wl%d: %s: no valid channel for \"%s\"\n",
+			  wlc->pub->unit, __func__, request->alpha2);
+	}
+
 	if (wlc->pub->_nbands > 1 || wlc->band->bandtype == BRCM_BAND_2G)
 		wlc_phy_chanspec_ch14_widefilter_set(wlc->band->pi,
 					brcms_c_japan_ccode(request->alpha2));