b43: N-PHY: fix logic in band switching

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/phy_n.c

@@ -3337,17 +3337,18 @@ static void b43_nphy_channel_setup(struct b43_wldev *dev,
 	struct b43_phy *phy = &dev->phy;
 	struct b43_phy_n *nphy = dev->phy.n;
 
-	u16 tmp;
+	u16 old_band_5ghz;
 	u32 tmp32;
 
-	tmp = b43_phy_read(dev, B43_NPHY_BANDCTL) & B43_NPHY_BANDCTL_5GHZ;
-	if (new_channel->band == IEEE80211_BAND_5GHZ && tmp == 0) {
+	old_band_5ghz =
+		b43_phy_read(dev, B43_NPHY_BANDCTL) & B43_NPHY_BANDCTL_5GHZ;
+	if (new_channel->band == IEEE80211_BAND_5GHZ && !old_band_5ghz) {
 		tmp32 = b43_read32(dev, B43_MMIO_PSM_PHY_HDR);
 		b43_write32(dev, B43_MMIO_PSM_PHY_HDR, tmp32 | 4);
 		b43_phy_set(dev, B43_PHY_B_BBCFG, 0xC000);
 		b43_write32(dev, B43_MMIO_PSM_PHY_HDR, tmp32);
 		b43_phy_set(dev, B43_NPHY_BANDCTL, B43_NPHY_BANDCTL_5GHZ);
-	} else if (new_channel->band == IEEE80211_BAND_5GHZ) {
+	} else if (new_channel->band == IEEE80211_BAND_2GHZ && old_band_5ghz) {
 		b43_phy_mask(dev, B43_NPHY_BANDCTL, ~B43_NPHY_BANDCTL_5GHZ);
 		tmp32 = b43_read32(dev, B43_MMIO_PSM_PHY_HDR);
 		b43_write32(dev, B43_MMIO_PSM_PHY_HDR, tmp32 | 4);