brcmsmac: write beacon period to hardware

Make brcms_c_set_beacon_period() write the beacon period to the
hardware if a new one is set.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -5551,10 +5551,20 @@ static void brcms_c_time_unlock(struct brcms_c_info *wlc)
 
 int brcms_c_set_beacon_period(struct brcms_c_info *wlc, u16 period)
 {
+	u32 bcnint_us;
+
 	if (period == 0)
 		return -EINVAL;
 
 	wlc->default_bss->beacon_period = period;
+
+	bcnint_us = period << 10;
+	brcms_c_time_lock(wlc);
+	bcma_write32(wlc->hw->d11core, D11REGOFFS(tsf_cfprep),
+		     (bcnint_us << CFPREP_CBI_SHIFT));
+	bcma_write32(wlc->hw->d11core, D11REGOFFS(tsf_cfpstart), bcnint_us);
+	brcms_c_time_unlock(wlc);
+
 	return 0;
 }