cfg80211: add rfkill support

To be easier on drivers and users, have cfg80211 register an
rfkill structure that drivers can access. When soft-killed,
simply take down all interfaces; when hard-killed the driver
needs to notify us and we will take down the interfaces
after the fact. While rfkilled, interfaces cannot be set UP.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

11 files changed, 172 insertions, 30 deletions

diff --git a/include/asm-generic/errno.h b/include/asm-generic/errno.h
index e8852c092fea..28cc03bf19e6 100644
--- a/include/asm-generic/errno.h
+++ b/include/asm-generic/errno.h
@@ -106,4 +106,6 @@
 #define EOWNERDEAD      130     /* Owner died */
 #define ENOTRECOVERABLE 131     /* State not recoverable */
 
+#define ERFKILL         132     /* Operation not possible due to RF-kill */
+
 #endif
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 8b8e4b893625..1a21895b732b 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -757,13 +757,11 @@ enum wiphy_params_flags {
  * @TX_POWER_AUTOMATIC: the dbm parameter is ignored
  * @TX_POWER_LIMITED: limit TX power by the dbm parameter
  * @TX_POWER_FIXED: fix TX power to the dbm parameter
- * @TX_POWER_OFF: turn off completely (will go away)
  */
 enum tx_power_setting {
         TX_POWER_AUTOMATIC,
         TX_POWER_LIMITED,
         TX_POWER_FIXED,
-        TX_POWER_OFF,
 };
 
 /**
@@ -855,8 +853,10 @@ enum tx_power_setting {
  *
  * @set_tx_power: set the transmit power according to the parameters
  * @get_tx_power: store the current TX power into the dbm variable;
- *      return 0 if successful; or -ENETDOWN if successful but power
- *      is disabled (this will go away)
+ *      return 0 if successful
+ *
+ * @rfkill_poll: polls the hw rfkill line, use cfg80211 reporting
+ *      functions to adjust rfkill hw state
  */
 struct cfg80211_ops {
         int     (*suspend)(struct wiphy *wiphy);
@@ -952,6 +952,8 @@ struct cfg80211_ops {
         int     (*set_tx_power)(struct wiphy *wiphy,
                                 enum tx_power_setting type, int dbm);
         int     (*get_tx_power)(struct wiphy *wiphy, int *dbm);
+
+        void    (*rfkill_poll)(struct wiphy *wiphy);
 };
 
 /*
@@ -1666,4 +1668,23 @@ void cfg80211_michael_mic_failure(struct net_device *dev, const u8 *addr,
  */
 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp);
 
+/**
+ * wiphy_rfkill_set_hw_state - notify cfg80211 about hw block state
+ * @wiphy: the wiphy
+ * @blocked: block status
+ */
+void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked);
+
+/**
+ * wiphy_rfkill_start_polling - start polling rfkill
+ * @wiphy: the wiphy
+ */
+void wiphy_rfkill_start_polling(struct wiphy *wiphy);
+
+/**
+ * wiphy_rfkill_stop_polling - stop polling rfkill
+ * @wiphy: the wiphy
+ */
+void wiphy_rfkill_stop_polling(struct wiphy *wiphy);
+
 #endif /* __NET_CFG80211_H */
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0270aa6e08f2..17d61d19d912 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -526,7 +526,7 @@ enum ieee80211_conf_flags {
 /**
  * enum ieee80211_conf_changed - denotes which configuration changed
  *
- * @IEEE80211_CONF_CHANGE_RADIO_ENABLED: the value of radio_enabled changed
+ * @_IEEE80211_CONF_CHANGE_RADIO_ENABLED: DEPRECATED
  * @IEEE80211_CONF_CHANGE_LISTEN_INTERVAL: the listen interval changed
  * @IEEE80211_CONF_CHANGE_RADIOTAP: the radiotap flag changed
  * @IEEE80211_CONF_CHANGE_PS: the PS flag or dynamic PS timeout changed
@@ -536,7 +536,7 @@ enum ieee80211_conf_flags {
  * @IEEE80211_CONF_CHANGE_IDLE: Idle flag changed
  */
 enum ieee80211_conf_changed {
-        IEEE80211_CONF_CHANGE_RADIO_ENABLED     = BIT(0),
+        _IEEE80211_CONF_CHANGE_RADIO_ENABLED    = BIT(0),
         IEEE80211_CONF_CHANGE_LISTEN_INTERVAL   = BIT(2),
         IEEE80211_CONF_CHANGE_RADIOTAP          = BIT(3),
         IEEE80211_CONF_CHANGE_PS                = BIT(4),
@@ -546,6 +546,14 @@ enum ieee80211_conf_changed {
         IEEE80211_CONF_CHANGE_IDLE              = BIT(8),
 };
 
+static inline __deprecated enum ieee80211_conf_changed
+__IEEE80211_CONF_CHANGE_RADIO_ENABLED(void)
+{
+        return _IEEE80211_CONF_CHANGE_RADIO_ENABLED;
+}
+#define IEEE80211_CONF_CHANGE_RADIO_ENABLED \
+        __IEEE80211_CONF_CHANGE_RADIO_ENABLED()
+
 /**
  * struct ieee80211_conf - configuration of the device
  *
@@ -585,7 +593,7 @@ struct ieee80211_conf {
         int max_sleep_period;
 
         u16 listen_interval;
-        bool radio_enabled;
+        bool __deprecated radio_enabled;
 
         u8 long_frame_max_tx_count, short_frame_max_tx_count;
 
@@ -1396,6 +1404,10 @@ enum ieee80211_ampdu_mlme_action {
  *      is the first frame we expect to perform the action on. Notice
  *      that TX/RX_STOP can pass NULL for this parameter.
  *      Returns a negative error code on failure.
+ *
+ * @rfkill_poll: Poll rfkill hardware state. If you need this, you also
+ *      need to set wiphy->rfkill_poll to %true before registration,
+ *      and need to call wiphy_rfkill_set_hw_state() in the callback.
  */
 struct ieee80211_ops {
         int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
@@ -1444,6 +1456,8 @@ struct ieee80211_ops {
         int (*ampdu_action)(struct ieee80211_hw *hw,
                             enum ieee80211_ampdu_mlme_action action,
                             struct ieee80211_sta *sta, u16 tid, u16 *ssn);
+
+        void (*rfkill_poll)(struct ieee80211_hw *hw);
 };
 
 /**
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 81258acf48bc..a9211cc183cb 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1340,7 +1340,6 @@ static int ieee80211_set_tx_power(struct wiphy *wiphy,
         struct ieee80211_local *local = wiphy_priv(wiphy);
         struct ieee80211_channel *chan = local->hw.conf.channel;
         u32 changes = 0;
-        bool radio_enabled = true;
 
         switch (type) {
         case TX_POWER_AUTOMATIC:
@@ -1359,14 +1358,6 @@ static int ieee80211_set_tx_power(struct wiphy *wiphy,
                         return -EINVAL;
                 local->user_power_level = dbm;
                 break;
-        case TX_POWER_OFF:
-                radio_enabled = false;
-                break;
-        }
-
-        if (radio_enabled != local->hw.conf.radio_enabled) {
-                changes |= IEEE80211_CONF_CHANGE_RADIO_ENABLED;
-                local->hw.conf.radio_enabled = radio_enabled;
         }
 
         ieee80211_hw_config(local, changes);
@@ -1380,12 +1371,16 @@ static int ieee80211_get_tx_power(struct wiphy *wiphy, int *dbm)
 
         *dbm = local->hw.conf.power_level;
 
-        if (!local->hw.conf.radio_enabled)
-                return -ENETDOWN;
-
         return 0;
 }
 
+static void ieee80211_rfkill_poll(struct wiphy *wiphy)
+{
+        struct ieee80211_local *local = wiphy_priv(wiphy);
+
+        drv_rfkill_poll(local);
+}
+
 struct cfg80211_ops mac80211_config_ops = {
         .add_virtual_intf = ieee80211_add_iface,
         .del_virtual_intf = ieee80211_del_iface,
@@ -1427,4 +1422,5 @@ struct cfg80211_ops mac80211_config_ops = {
         .set_wiphy_params = ieee80211_set_wiphy_params,
         .set_tx_power = ieee80211_set_tx_power,
         .get_tx_power = ieee80211_get_tx_power,
+        .rfkill_poll = ieee80211_rfkill_poll,
 };
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 3912b5334b9c..b13446afd48f 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -181,4 +181,11 @@ static inline int drv_ampdu_action(struct ieee80211_local *local,
                                                 sta, tid, ssn);
         return -EOPNOTSUPP;
 }
+
+
+static inline void drv_rfkill_poll(struct ieee80211_local *local)
+{
+        if (local->ops->rfkill_poll)
+                local->ops->rfkill_poll(&local->hw);
+}
 #endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 8c9f1c722cdb..b7c8a4484298 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -170,7 +170,7 @@ static int ieee80211_open(struct net_device *dev)
                         goto err_del_bss;
                 /* we're brought up, everything changes */
                 hw_reconf_flags = ~0;
-                ieee80211_led_radio(local, local->hw.conf.radio_enabled);
+                ieee80211_led_radio(local, true);
         }
 
         /*
@@ -560,7 +560,7 @@ static int ieee80211_stop(struct net_device *dev)
 
                 drv_stop(local);
 
-                ieee80211_led_radio(local, 0);
+                ieee80211_led_radio(local, false);
 
                 flush_workqueue(local->hw.workqueue);
 
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 31284c984e38..22f63815fb36 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -973,7 +973,7 @@ int ieee80211_reconfig(struct ieee80211_local *local)
         if (local->open_count) {
                 res = drv_start(local);
 
-                ieee80211_led_radio(local, hw->conf.radio_enabled);
+                ieee80211_led_radio(local, true);
         }
 
         /* add interfaces */
diff --git a/net/wireless/Kconfig b/net/wireless/Kconfig
index 45005497c634..4428dd5e911d 100644
--- a/net/wireless/Kconfig
+++ b/net/wireless/Kconfig
@@ -1,5 +1,6 @@
 config CFG80211
-        tristate "Improved wireless configuration API"
+        tristate "Improved wireless configuration API"
+        depends on RFKILL || !RFKILL
 
 config CFG80211_REG_DEBUG
         bool "cfg80211 regulatory debugging"
diff --git a/net/wireless/core.c b/net/wireless/core.c
index a5dbea1da476..3b74b88e10a3 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -12,6 +12,7 @@
 #include <linux/debugfs.h>
 #include <linux/notifier.h>
 #include <linux/device.h>
+#include <linux/rtnetlink.h>
 #include <net/genetlink.h>
 #include <net/cfg80211.h>
 #include "nl80211.h"
@@ -227,6 +228,41 @@ int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
         return 0;
 }
 
+static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
+{
+        struct cfg80211_registered_device *drv = data;
+
+        drv->ops->rfkill_poll(&drv->wiphy);
+}
+
+static int cfg80211_rfkill_set_block(void *data, bool blocked)
+{
+        struct cfg80211_registered_device *drv = data;
+        struct wireless_dev *wdev;
+
+        if (!blocked)
+                return 0;
+
+        rtnl_lock();
+        mutex_lock(&drv->devlist_mtx);
+
+        list_for_each_entry(wdev, &drv->netdev_list, list)
+                dev_close(wdev->netdev);
+
+        mutex_unlock(&drv->devlist_mtx);
+        rtnl_unlock();
+
+        return 0;
+}
+
+static void cfg80211_rfkill_sync_work(struct work_struct *work)
+{
+        struct cfg80211_registered_device *drv;
+
+        drv = container_of(work, struct cfg80211_registered_device, rfkill_sync);
+        cfg80211_rfkill_set_block(drv, rfkill_blocked(drv->rfkill));
+}
+
 /* exported functions */
 
 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
@@ -274,6 +310,18 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
         drv->wiphy.dev.class = &ieee80211_class;
         drv->wiphy.dev.platform_data = drv;
 
+        drv->rfkill_ops.set_block = cfg80211_rfkill_set_block;
+        drv->rfkill = rfkill_alloc(dev_name(&drv->wiphy.dev),
+                                   &drv->wiphy.dev, RFKILL_TYPE_WLAN,
+                                   &drv->rfkill_ops, drv);
+
+        if (!drv->rfkill) {
+                kfree(drv);
+                return NULL;
+        }
+
+        INIT_WORK(&drv->rfkill_sync, cfg80211_rfkill_sync_work);
+
         /*
          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
          * Fragmentation and RTS threshold are disabled by default with the
@@ -356,6 +404,10 @@ int wiphy_register(struct wiphy *wiphy)
         if (res)
                 goto out_unlock;
 
+        res = rfkill_register(drv->rfkill);
+        if (res)
+                goto out_rm_dev;
+
         list_add(&drv->list, &cfg80211_drv_list);
 
         /* add to debugfs */
@@ -379,16 +431,41 @@ int wiphy_register(struct wiphy *wiphy)
         cfg80211_debugfs_drv_add(drv);
 
         res = 0;
-out_unlock:
+        goto out_unlock;
+
+ out_rm_dev:
+        device_del(&drv->wiphy.dev);
+ out_unlock:
         mutex_unlock(&cfg80211_mutex);
         return res;
 }
 EXPORT_SYMBOL(wiphy_register);
 
+void wiphy_rfkill_start_polling(struct wiphy *wiphy)
+{
+        struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
+
+        if (!drv->ops->rfkill_poll)
+                return;
+        drv->rfkill_ops.poll = cfg80211_rfkill_poll;
+        rfkill_resume_polling(drv->rfkill);
+}
+EXPORT_SYMBOL(wiphy_rfkill_start_polling);
+
+void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
+{
+        struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
+
+        rfkill_pause_polling(drv->rfkill);
+}
+EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
+
 void wiphy_unregister(struct wiphy *wiphy)
 {
         struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
 
+        rfkill_unregister(drv->rfkill);
+
         /* protect the device list */
         mutex_lock(&cfg80211_mutex);
 
@@ -425,6 +502,7 @@ EXPORT_SYMBOL(wiphy_unregister);
 void cfg80211_dev_free(struct cfg80211_registered_device *drv)
 {
         struct cfg80211_internal_bss *scan, *tmp;
+        rfkill_destroy(drv->rfkill);
         mutex_destroy(&drv->mtx);
         mutex_destroy(&drv->devlist_mtx);
         list_for_each_entry_safe(scan, tmp, &drv->bss_list, list)
@@ -438,6 +516,15 @@ void wiphy_free(struct wiphy *wiphy)
 }
 EXPORT_SYMBOL(wiphy_free);
 
+void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
+{
+        struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
+
+        if (rfkill_set_hw_state(drv->rfkill, blocked))
+                schedule_work(&drv->rfkill_sync);
+}
+EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
+
 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
                                          unsigned long state,
                                          void *ndev)
@@ -446,7 +533,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
         struct cfg80211_registered_device *rdev;
 
         if (!dev->ieee80211_ptr)
-                return 0;
+                return NOTIFY_DONE;
 
         rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
 
@@ -492,9 +579,13 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
                 }
                 mutex_unlock(&rdev->devlist_mtx);
                 break;
+        case NETDEV_PRE_UP:
+                if (rfkill_blocked(rdev->rfkill))
+                        return notifier_from_errno(-ERFKILL);
+                break;
         }
 
-        return 0;
+        return NOTIFY_DONE;
 }
 
 static struct notifier_block cfg80211_netdev_notifier = {
diff --git a/net/wireless/core.h b/net/wireless/core.h
index ab512bcd8153..bfa340c7abb5 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -11,6 +11,8 @@
 #include <linux/kref.h>
 #include <linux/rbtree.h>
 #include <linux/debugfs.h>
+#include <linux/rfkill.h>
+#include <linux/workqueue.h>
 #include <net/genetlink.h>
 #include <net/cfg80211.h>
 #include "reg.h"
@@ -24,6 +26,11 @@ struct cfg80211_registered_device {
          * any call is in progress */
         struct mutex mtx;
 
+        /* rfkill support */
+        struct rfkill_ops rfkill_ops;
+        struct rfkill *rfkill;
+        struct work_struct rfkill_sync;
+
         /* ISO / IEC 3166 alpha2 for which this device is receiving
          * country IEs on, this can help disregard country IEs from APs
          * on the same alpha2 quickly. The alpha2 may differ from
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 9fbfb8536e75..d030c5315672 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -764,6 +764,8 @@ int cfg80211_wext_siwtxpower(struct net_device *dev,
 
         /* only change when not disabling */
         if (!data->txpower.disabled) {
+                rfkill_set_sw_state(rdev->rfkill, false);
+
                 if (data->txpower.fixed) {
                         /*
                          * wext doesn't support negative values, see
@@ -787,7 +789,9 @@ int cfg80211_wext_siwtxpower(struct net_device *dev,
                         }
                 }
         } else {
-                type = TX_POWER_OFF;
+                rfkill_set_sw_state(rdev->rfkill, true);
+                schedule_work(&rdev->rfkill_sync);
+                return 0;
         }
 
         return rdev->ops->set_tx_power(wdev->wiphy, type, dbm);;
@@ -811,13 +815,12 @@ int cfg80211_wext_giwtxpower(struct net_device *dev,
                 return -EOPNOTSUPP;
 
         err = rdev->ops->get_tx_power(wdev->wiphy, &val);
-        /* HACK!!! */
-        if (err && err != -ENETDOWN)
+        if (err)
                 return err;
 
         /* well... oh well */
         data->txpower.fixed = 1;
-        data->txpower.disabled = err == -ENETDOWN;
+        data->txpower.disabled = rfkill_blocked(rdev->rfkill);
         data->txpower.value = val;
         data->txpower.flags = IW_TXPOW_DBM;