[B43LEGACY]: Support for turning the radio off from software.

This adds support for turning the radio off in software.
That's useful in environments, where you don't want the RF
to radiate any signals, but don't want to bring the interface down.

This patch is based on a similar patch of b43 by Michael Buesch.
Signed-off-by: Larry Finger <larry.finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wireless/b43legacy/b43legacy.h

@@ -411,7 +411,6 @@ struct b43legacy_phy {
 	u8 calibrated:1;
 	u8 radio_rev;		/* Radio revision */
 
-	bool radio_on;		/* Radio switched on/off */
 	bool locked;		/* Only used in b43legacy_phy_{un}lock() */
 	bool dyn_tssi_tbl;	/* tssi2dbm is kmalloc()ed. */
 
@@ -420,6 +419,16 @@ struct b43legacy_phy {
 	bool aci_wlan_automatic;
 	bool aci_hw_rssi;
 
+	/* Radio switched on/off */
+	bool radio_on;
+	struct {
+		/* Values saved when turning the radio off.
+		 * They are needed when turning it on again. */
+		bool valid;
+		u16 rfover;
+		u16 rfoverval;
+	} radio_off_context;
+
 	u16 minlowsig[2];
 	u16 minlowsigpos[2];
 

drivers/net/wireless/b43legacy/main.c

@@ -2660,6 +2660,22 @@ static int b43legacy_dev_config(struct ieee80211_hw *hw,
 		b43legacy_set_beacon_int(dev, conf->beacon_int);
 
 
+	if (!!conf->radio_enabled != phy->radio_on) {
+		if (conf->radio_enabled) {
+			b43legacy_radio_turn_on(dev);
+			b43legacyinfo(dev->wl, "Radio turned on by software\n");
+			if (!dev->radio_hw_enable)
+				b43legacyinfo(dev->wl, "The hardware RF-kill"
+					      " button still turns the radio"
+					      " physically off. Press the"
+					      " button to turn it on.\n");
+		} else {
+			b43legacy_radio_turn_off(dev);
+			b43legacyinfo(dev->wl, "Radio turned off by"
+				      " software\n");
+		}
+	}
+
 	spin_lock_irqsave(&wl->irq_lock, flags);
 	b43legacy_interrupt_enable(dev, savedirqs);
 	mmiowb();

drivers/net/wireless/b43legacy/phy.c

@@ -462,12 +462,7 @@ static void b43legacy_phy_initb2(struct b43legacy_wldev *dev)
 		val -= 0x0202;
 	}
 	b43legacy_phy_write(dev, 0x03E4, 0x3000);
-	if (phy->channel == 0xFF)
-		b43legacy_radio_selectchannel(dev,
-					B43legacy_RADIO_DEFAULT_CHANNEL_BG,
-					0);
-	else
-		b43legacy_radio_selectchannel(dev, phy->channel, 0);
+	b43legacy_radio_selectchannel(dev, phy->channel, 0);
 	if (phy->radio_ver != 0x2050) {
 		b43legacy_radio_write16(dev, 0x0075, 0x0080);
 		b43legacy_radio_write16(dev, 0x0079, 0x0081);
@@ -516,12 +511,7 @@ static void b43legacy_phy_initb4(struct b43legacy_wldev *dev)
 		val -= 0x0202;
 	}
 	b43legacy_phy_write(dev, 0x03E4, 0x3000);
-	if (phy->channel == 0xFF)
-		b43legacy_radio_selectchannel(dev,
-					B43legacy_RADIO_DEFAULT_CHANNEL_BG,
-					0);
-	else
-		b43legacy_radio_selectchannel(dev, phy->channel, 0);
+	b43legacy_radio_selectchannel(dev, phy->channel, 0);
 	if (phy->radio_ver != 0x2050) {
 		b43legacy_radio_write16(dev, 0x0075, 0x0080);
 		b43legacy_radio_write16(dev, 0x0079, 0x0081);

drivers/net/wireless/b43legacy/radio.c

@@ -1767,6 +1767,17 @@ int b43legacy_radio_selectchannel(struct b43legacy_wldev *dev,
 {
 	struct b43legacy_phy *phy = &dev->phy;
 
+	if (channel == 0xFF) {
+		switch (phy->type) {
+		case B43legacy_PHYTYPE_B:
+		case B43legacy_PHYTYPE_G:
+			channel = B43legacy_RADIO_DEFAULT_CHANNEL_BG;
+			break;
+		default:
+			B43legacy_WARN_ON(1);
+		}
+	}
+
 /* TODO: Check if channel is valid - return -EINVAL if not */
 	if (synthetic_pu_workaround)
 		b43legacy_synth_pu_workaround(dev, channel);
@@ -2070,6 +2081,7 @@ void b43legacy_radio_turn_on(struct b43legacy_wldev *dev)
 {
 	struct b43legacy_phy *phy = &dev->phy;
 	int err;
+	u8 channel;
 
 	might_sleep();
 
@@ -2083,15 +2095,24 @@ void b43legacy_radio_turn_on(struct b43legacy_wldev *dev)
 		b43legacy_phy_write(dev, 0x0015, 0xCC00);
 		b43legacy_phy_write(dev, 0x0015,
 				    (phy->gmode ? 0x00C0 : 0x0000));
+		if (phy->radio_off_context.valid) {
+			/* Restore the RFover values. */
+			b43legacy_phy_write(dev, B43legacy_PHY_RFOVER,
+					    phy->radio_off_context.rfover);
+			b43legacy_phy_write(dev, B43legacy_PHY_RFOVERVAL,
+					    phy->radio_off_context.rfoverval);
+			phy->radio_off_context.valid = 0;
+		}
+		channel = phy->channel;
 		err = b43legacy_radio_selectchannel(dev,
 					B43legacy_RADIO_DEFAULT_CHANNEL_BG, 1);
-		B43legacy_WARN_ON(err != 0);
+		err |= b43legacy_radio_selectchannel(dev, channel, 0);
+		B43legacy_WARN_ON(err);
 		break;
 	default:
 		B43legacy_BUG_ON(1);
 	}
 	phy->radio_on = 1;
-	b43legacydbg(dev->wl, "Radio turned on\n");
 	b43legacy_leds_update(dev, 0);
 }
 
@@ -2100,10 +2121,16 @@ void b43legacy_radio_turn_off(struct b43legacy_wldev *dev)
 	struct b43legacy_phy *phy = &dev->phy;
 
 	if (phy->type == B43legacy_PHYTYPE_G && dev->dev->id.revision >= 5) {
-		b43legacy_phy_write(dev, 0x0811, b43legacy_phy_read(dev, 0x0811)
-				    | 0x008C);
-		b43legacy_phy_write(dev, 0x0812, b43legacy_phy_read(dev, 0x0812)
-				    & 0xFF73);
+		u16 rfover, rfoverval;
+
+		rfover = b43legacy_phy_read(dev, B43legacy_PHY_RFOVER);
+		rfoverval = b43legacy_phy_read(dev, B43legacy_PHY_RFOVERVAL);
+		phy->radio_off_context.rfover = rfover;
+		phy->radio_off_context.rfoverval = rfoverval;
+		phy->radio_off_context.valid = 1;
+		b43legacy_phy_write(dev, B43legacy_PHY_RFOVER, rfover | 0x008C);
+		b43legacy_phy_write(dev, B43legacy_PHY_RFOVERVAL,
+				    rfoverval & 0xFF73);
 	} else
 		b43legacy_phy_write(dev, 0x0015, 0xAA00);
 	phy->radio_on = 0;