b43: HT-PHY: Implement band switching

It works pretty much the same way as in N-PHY.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/b43.h

@@ -476,6 +476,11 @@ enum {
 #define B43_MACCMD_CCA			0x00000008	/* Clear channel assessment */
 #define B43_MACCMD_BGNOISE		0x00000010	/* Background noise */
 
+/* B43_MMIO_PSM_PHY_HDR bits */
+#define B43_PSM_HDR_MAC_PHY_RESET	0x00000001
+#define B43_PSM_HDR_MAC_PHY_CLOCK_EN	0x00000002
+#define B43_PSM_HDR_MAC_PHY_FORCE_CLK	0x00000004
+
 /* See BCMA_CLKCTLST_EXTRESREQ and BCMA_CLKCTLST_EXTRESST */
 #define B43_BCMA_CLKCTLST_80211_PLL_REQ	0x00000100
 #define B43_BCMA_CLKCTLST_PHY_PLL_REQ	0x00000200

drivers/net/wireless/b43/phy_ht.c

@@ -321,6 +321,26 @@ static void b43_phy_ht_bphy_init(struct b43_wldev *dev)
 	b43_phy_write(dev, B43_PHY_N_BMODE(0x38), 0x668);
 }
 
+static void b43_phy_ht_bphy_reset(struct b43_wldev *dev, bool reset)
+{
+	u16 tmp;
+
+	tmp = b43_read16(dev, B43_MMIO_PSM_PHY_HDR);
+	b43_write16(dev, B43_MMIO_PSM_PHY_HDR,
+		    tmp | B43_PSM_HDR_MAC_PHY_FORCE_CLK);
+
+	/* Put BPHY in or take it out of the reset */
+	if (reset)
+		b43_phy_set(dev, B43_PHY_B_BBCFG,
+			    B43_PHY_B_BBCFG_RSTCCA | B43_PHY_B_BBCFG_RSTRX);
+	else
+		b43_phy_mask(dev, B43_PHY_B_BBCFG,
+			     (u16)~(B43_PHY_B_BBCFG_RSTCCA |
+				    B43_PHY_B_BBCFG_RSTRX));
+
+	b43_write16(dev, B43_MMIO_PSM_PHY_HDR, tmp);
+}
+
 /**************************************************
  * Samples
  **************************************************/
@@ -757,13 +777,19 @@ static void b43_phy_ht_channel_setup(struct b43_wldev *dev,
 				const struct b43_phy_ht_channeltab_e_phy *e,
 				struct ieee80211_channel *new_channel)
 {
-	bool old_band_5ghz;
+	if (new_channel->band == IEEE80211_BAND_5GHZ) {
+		/* Switch to 2 GHz for a moment to access B-PHY regs */
+		b43_phy_mask(dev, B43_PHY_HT_BANDCTL, ~B43_PHY_HT_BANDCTL_5GHZ);
+
+		b43_phy_ht_bphy_reset(dev, true);
+
+		/* Switch to 5 GHz */
+		b43_phy_set(dev, B43_PHY_HT_BANDCTL, B43_PHY_HT_BANDCTL_5GHZ);
+	} else {
+		/* Switch to 2 GHz */
+		b43_phy_mask(dev, B43_PHY_HT_BANDCTL, ~B43_PHY_HT_BANDCTL_5GHZ);
 
-	old_band_5ghz = b43_phy_read(dev, B43_PHY_HT_BANDCTL) & 0; /* FIXME */
-	if (new_channel->band == IEEE80211_BAND_5GHZ && !old_band_5ghz) {
-		/* TODO */
-	} else if (new_channel->band == IEEE80211_BAND_2GHZ && old_band_5ghz) {
-		/* TODO */
+		b43_phy_ht_bphy_reset(dev, false);
 	}
 
 	b43_phy_write(dev, B43_PHY_HT_BW1, e->bw1);

drivers/net/wireless/b43/phy_ht.h

@@ -106,6 +106,9 @@
 #define  B43_PHY_HT_TXPCTL_TARG_PWR2_C3_SHIFT	0
 #define B43_PHY_HT_TX_PCTL_STATUS_C3		B43_PHY_EXTG(0x169)
 
+#define B43_PHY_B_BBCFG				B43_PHY_N_BMODE(0x001)
+#define  B43_PHY_B_BBCFG_RSTCCA			0x4000 /* Reset CCA */
+#define  B43_PHY_B_BBCFG_RSTRX			0x8000 /* Reset RX */
 #define B43_PHY_HT_TEST				B43_PHY_N_BMODE(0x00A)