rt2x00: Fix rfkill polling prior to interface start.

commit a396e10019eaf3809b0219c966865aaafec12630 upstream.

We need to program the rfkill switch GPIO pin direction to input at
device initialization time, not only when the interface is brought up.
Doing this only when the interface is brought up could lead to rfkill
detecting the switch is turned on erroneously and inability to create
the interface and bringing it up.

Reported-and-tested-by: Andreas Messer <andi@bastelmap.de>
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo Van Doorn <ivdoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index b66b8b4..e0a7efc 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -1768,6 +1768,7 @@
 static int rt2500usb_probe_hw(struct rt2x00_dev *rt2x00dev)
 {
 	int retval;
+	u16 reg;
 
 	/*
 	 * Allocate eeprom data.
@@ -1781,6 +1782,14 @@
 		return retval;
 
 	/*
+	 * Enable rfkill polling by setting GPIO direction of the
+	 * rfkill switch GPIO pin correctly.
+	 */
+	rt2500usb_register_read(rt2x00dev, MAC_CSR19, &reg);
+	rt2x00_set_field16(&reg, MAC_CSR19_BIT8, 0);
+	rt2500usb_register_write(rt2x00dev, MAC_CSR19, reg);
+
+	/*
 	 * Initialize hw specifications.
 	 */
 	retval = rt2500usb_probe_hw_mode(rt2x00dev);