[PATCH] rt2x00: Fix rfkill handling

As reported by Modestas Vainius, enabling rkfill in 1 driver and
disabling it in a second could cause a NULL pointer exception when
the rfkill-disabled driver still sets the CONFIG_SUPPORT_HW_BUTTON flag.

Furthermore, rfkill expects the timeout as a value in milliseconds
instead of jiffies. Also increase the timeout to a second,
since this 250ms would be overkill.

Also the flag DEVICE_ENABLED_RADIO_HW is causing problems
for devices which do not support the hardware button
while rfkill is enabled in the driver.

To remidy this we should inverse the flag and its meaning,
rename the flag to DEVICE_DISABLED_RADIO_HW this means that
by default the radio is enabled by the hardware button (if present)
and can only be disabled explicitely.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2400pci.c

@@ -244,6 +244,8 @@ static int rt2400pci_rfkill_poll(struct rt2x00_dev *rt2x00dev)
 	rt2x00pci_register_read(rt2x00dev, GPIOCSR, &reg);
 	return rt2x00_get_field32(reg, GPIOCSR_BIT0);
 }
+#else
+#define rt2400pci_rfkill_poll	NULL
 #endif /* CONFIG_RT2400PCI_RFKILL */
 
 /*
@@ -1359,8 +1361,10 @@ static int rt2400pci_init_eeprom(struct rt2x00_dev *rt2x00dev)
 	/*
 	 * Detect if this device has an hardware controlled radio.
 	 */
+#ifdef CONFIG_RT2400PCI_RFKILL
 	if (rt2x00_get_field16(eeprom, EEPROM_ANTENNA_HARDWARE_RADIO))
 		__set_bit(CONFIG_SUPPORT_HW_BUTTON, &rt2x00dev->flags);
+#endif /* CONFIG_RT2400PCI_RFKILL */
 
 	/*
 	 * Check if the BBP tuning should be enabled.
@@ -1625,9 +1629,7 @@ static const struct rt2x00lib_ops rt2400pci_rt2x00_ops = {
 	.initialize		= rt2x00pci_initialize,
 	.uninitialize		= rt2x00pci_uninitialize,
 	.set_device_state	= rt2400pci_set_device_state,
-#ifdef CONFIG_RT2400PCI_RFKILL
 	.rfkill_poll		= rt2400pci_rfkill_poll,
-#endif /* CONFIG_RT2400PCI_RFKILL */
 	.link_stats		= rt2400pci_link_stats,
 	.reset_tuner		= rt2400pci_reset_tuner,
 	.link_tuner		= rt2400pci_link_tuner,

drivers/net/wireless/rt2x00/rt2500pci.c

@@ -244,6 +244,8 @@ static int rt2500pci_rfkill_poll(struct rt2x00_dev *rt2x00dev)
 	rt2x00pci_register_read(rt2x00dev, GPIOCSR, &reg);
 	return rt2x00_get_field32(reg, GPIOCSR_BIT0);
 }
+#else
+#define rt2500pci_rfkill_poll	NULL
 #endif /* CONFIG_RT2500PCI_RFKILL */
 
 /*
@@ -1530,8 +1532,10 @@ static int rt2500pci_init_eeprom(struct rt2x00_dev *rt2x00dev)
 	/*
 	 * Detect if this device has an hardware controlled radio.
 	 */
+#ifdef CONFIG_RT2500PCI_RFKILL
 	if (rt2x00_get_field16(eeprom, EEPROM_ANTENNA_HARDWARE_RADIO))
 		__set_bit(CONFIG_SUPPORT_HW_BUTTON, &rt2x00dev->flags);
+#endif /* CONFIG_RT2500PCI_RFKILL */
 
 	/*
 	 * Check if the BBP tuning should be enabled.
@@ -1937,9 +1941,7 @@ static const struct rt2x00lib_ops rt2500pci_rt2x00_ops = {
 	.initialize		= rt2x00pci_initialize,
 	.uninitialize		= rt2x00pci_uninitialize,
 	.set_device_state	= rt2500pci_set_device_state,
-#ifdef CONFIG_RT2500PCI_RFKILL
 	.rfkill_poll		= rt2500pci_rfkill_poll,
-#endif /* CONFIG_RT2500PCI_RFKILL */
 	.link_stats		= rt2500pci_link_stats,
 	.reset_tuner		= rt2500pci_reset_tuner,
 	.link_tuner		= rt2500pci_link_tuner,

drivers/net/wireless/rt2x00/rt2x00.h

@@ -451,7 +451,7 @@ enum rt2x00_flags {
 	DEVICE_STARTED,
 	DEVICE_STARTED_SUSPEND,
 	DEVICE_ENABLED_RADIO,
-	DEVICE_ENABLED_RADIO_HW,
+	DEVICE_DISABLED_RADIO_HW,
 
 	/*
 	 * Driver features

drivers/net/wireless/rt2x00/rt2x00dev.c

@@ -104,8 +104,7 @@ int rt2x00lib_enable_radio(struct rt2x00_dev *rt2x00dev)
 	 * And check if the hardware button has been disabled.
 	 */
 	if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
-	    (test_bit(CONFIG_SUPPORT_HW_BUTTON, &rt2x00dev->flags) &&
-	     !test_bit(DEVICE_ENABLED_RADIO_HW, &rt2x00dev->flags)))
+	    test_bit(DEVICE_DISABLED_RADIO_HW, &rt2x00dev->flags))
 		return 0;
 
 	/*

drivers/net/wireless/rt2x00/rt2x00lib.h

@@ -28,9 +28,10 @@
 
 /*
  * Interval defines
+ * Both the link tuner as the rfkill will be called once per second.
  */
 #define LINK_TUNE_INTERVAL	( round_jiffies(HZ) )
-#define RFKILL_POLL_INTERVAL	( HZ / 4 )
+#define RFKILL_POLL_INTERVAL	( 1000 )
 
 /*
  * Radio control handlers.
@@ -98,13 +99,6 @@ void rt2x00rfkill_free(struct rt2x00_dev *rt2x00dev);
 #else
 static inline int rt2x00rfkill_register(struct rt2x00_dev *rt2x00dev)
 {
-	/*
-	 * Force enable this flag, this will assure that
-	 * devices with a hardware button but without rfkill support
-	 * can still use their hardware.
-	 */
-	__set_bit(DEVICE_ENABLED_RADIO_HW, &rt2x00dev->flags);
-
 	return 0;
 }
 

drivers/net/wireless/rt2x00/rt2x00rfkill.c

@@ -52,11 +52,11 @@ static int rt2x00rfkill_toggle_radio(void *data, enum rfkill_state state)
 
 	if (state == RFKILL_STATE_ON) {
 		INFO(rt2x00dev, "Hardware button pressed, enabling radio.\n");
-		__set_bit(DEVICE_ENABLED_RADIO_HW, &rt2x00dev->flags);
+		__clear_bit(DEVICE_DISABLED_RADIO_HW, &rt2x00dev->flags);
 		retval = rt2x00lib_enable_radio(rt2x00dev);
 	} else if (state == RFKILL_STATE_OFF) {
 		INFO(rt2x00dev, "Hardware button pressed, disabling radio.\n");
-		__clear_bit(DEVICE_ENABLED_RADIO_HW, &rt2x00dev->flags);
+		__set_bit(DEVICE_DISABLED_RADIO_HW, &rt2x00dev->flags);
 		rt2x00lib_disable_radio(rt2x00dev);
 	}
 

drivers/net/wireless/rt2x00/rt61pci.c

@@ -269,6 +269,8 @@ static int rt61pci_rfkill_poll(struct rt2x00_dev *rt2x00dev)
 	rt2x00pci_register_read(rt2x00dev, MAC_CSR13, &reg);
 	return rt2x00_get_field32(reg, MAC_CSR13_BIT5);;
 }
+#else
+#define rt61pci_rfkill_poll	NULL
 #endif /* CONFIG_RT61PCI_RFKILL */
 
 /*
@@ -2090,8 +2092,10 @@ static int rt61pci_init_eeprom(struct rt2x00_dev *rt2x00dev)
 	/*
 	 * Detect if this device has an hardware controlled radio.
 	 */
+#ifdef CONFIG_RT61PCI_RFKILL
 	if (rt2x00_get_field16(eeprom, EEPROM_ANTENNA_HARDWARE_RADIO))
 		__set_bit(CONFIG_SUPPORT_HW_BUTTON, &rt2x00dev->flags);
+#endif /* CONFIG_RT61PCI_RFKILL */
 
 	/*
 	 * Read frequency offset and RF programming sequence.
@@ -2531,9 +2535,7 @@ static const struct rt2x00lib_ops rt61pci_rt2x00_ops = {
 	.initialize		= rt2x00pci_initialize,
 	.uninitialize		= rt2x00pci_uninitialize,
 	.set_device_state	= rt61pci_set_device_state,
-#ifdef CONFIG_RT61PCI_RFKILL
 	.rfkill_poll		= rt61pci_rfkill_poll,
-#endif /* CONFIG_RT61PCI_RFKILL */
 	.link_stats		= rt61pci_link_stats,
 	.reset_tuner		= rt61pci_reset_tuner,
 	.link_tuner		= rt61pci_link_tuner,