4 files changed, 287 insertions, 87 deletions

diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt
index b65f0799df48..4d3ee317a4a3 100644
--- a/Documentation/rfkill.txt
+++ b/Documentation/rfkill.txt
@@ -191,12 +191,20 @@ Userspace input handlers (uevents) or kernel input handlers (rfkill-input):
           to tell the devices registered with the rfkill class to change
           their state (i.e. translates the input layer event into real
           action).
+
         * rfkill-input implements EPO by handling EV_SW SW_RFKILL_ALL 0
           (power off all transmitters) in a special way: it ignores any
           overrides and local state cache and forces all transmitters to the
           RFKILL_STATE_SOFT_BLOCKED state (including those which are already
-          supposed to be BLOCKED).  Note that the opposite event (power on all
-          transmitters) is handled normally.
+          supposed to be BLOCKED).
+        * rfkill EPO will remain active until rfkill-input receives an
+          EV_SW SW_RFKILL_ALL 1 event.  While the EPO is active, transmitters
+          are locked in the blocked state (rfkill will refuse to unblock them).
+        * rfkill-input implements different policies that the user can
+          select for handling EV_SW SW_RFKILL_ALL 1.  It will unlock rfkill,
+          and either do nothing (leave transmitters blocked, but now unlocked),
+          restore the transmitters to their state before the EPO, or unblock
+          them all.
 
 Userspace uevent handler or kernel platform-specific drivers hooked to the
 rfkill notifier chain:
@@ -331,11 +339,9 @@ class to get a sysfs interface :-)
 correct event for your switch/button.  These events are emergency power-off
 events when they are trying to turn the transmitters off.  An example of an
 input device which SHOULD generate *_RFKILL_ALL events is the wireless-kill
-switch in a laptop which is NOT a hotkey, but a real switch that kills radios
-in hardware, even if the O.S. has gone to lunch.  An example of an input device
-which SHOULD NOT generate *_RFKILL_ALL events by default, is any sort of hot
-key that does nothing by itself, as well as any hot key that is type-specific
-(e.g. the one for WLAN).
+switch in a laptop which is NOT a hotkey, but a real sliding/rocker switch.
+An example of an input device which SHOULD NOT generate *_RFKILL_ALL events by
+default, is any sort of hot key that is type-specific (e.g. the one for WLAN).
 
 
 3.1 Guidelines for wireless device drivers
diff --git a/net/rfkill/rfkill-input.c b/net/rfkill/rfkill-input.c
index bfdade72e066..7706541f9f79 100644
--- a/net/rfkill/rfkill-input.c
+++ b/net/rfkill/rfkill-input.c
@@ -24,138 +24,291 @@ MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
 MODULE_DESCRIPTION("Input layer to RF switch connector");
 MODULE_LICENSE("GPL");
 
+enum rfkill_input_master_mode {
+        RFKILL_INPUT_MASTER_DONOTHING = 0,
+        RFKILL_INPUT_MASTER_RESTORE = 1,
+        RFKILL_INPUT_MASTER_UNBLOCKALL = 2,
+        RFKILL_INPUT_MASTER_MAX,        /* marker */
+};
+
+static enum rfkill_input_master_mode rfkill_master_switch_mode =
+                                        RFKILL_INPUT_MASTER_UNBLOCKALL;
+module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0);
+MODULE_PARM_DESC(master_switch_mode,
+        "SW_RFKILL_ALL ON should: 0=do nothing; 1=restore; 2=unblock all");
+
+enum rfkill_global_sched_op {
+        RFKILL_GLOBAL_OP_EPO = 0,
+        RFKILL_GLOBAL_OP_RESTORE,
+        RFKILL_GLOBAL_OP_UNLOCK,
+        RFKILL_GLOBAL_OP_UNBLOCK,
+};
+
+/*
+ * Currently, the code marked with RFKILL_NEED_SWSET is inactive.
+ * If handling of EV_SW SW_WLAN/WWAN/BLUETOOTH/etc is needed in the
+ * future, when such events are added, that code will be necessary.
+ */
+
 struct rfkill_task {
         struct work_struct work;
-        enum rfkill_type type;
-        struct mutex mutex; /* ensures that task is serialized */
-        spinlock_t lock; /* for accessing last and desired state */
-        unsigned long last; /* last schedule */
-        enum rfkill_state desired_state; /* on/off */
+
+        /* ensures that task is serialized */
+        struct mutex mutex;
+
+        /* protects everything below */
+        spinlock_t lock;
+
+        /* pending regular switch operations (1=pending) */
+        unsigned long sw_pending[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
+
+#ifdef RFKILL_NEED_SWSET
+        /* set operation pending (1=pending) */
+        unsigned long sw_setpending[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
+
+        /* desired state for pending set operation (1=unblock) */
+        unsigned long sw_newstate[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
+#endif
+
+        /* should the state be complemented (1=yes) */
+        unsigned long sw_togglestate[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
+
+        bool global_op_pending;
+        enum rfkill_global_sched_op op;
 };
 
-static void rfkill_task_handler(struct work_struct *work)
+static void __rfkill_handle_global_op(enum rfkill_global_sched_op op)
 {
-        struct rfkill_task *task = container_of(work, struct rfkill_task, work);
+        unsigned int i;
+
+        switch (op) {
+        case RFKILL_GLOBAL_OP_EPO:
+                rfkill_epo();
+                break;
+        case RFKILL_GLOBAL_OP_RESTORE:
+                rfkill_restore_states();
+                break;
+        case RFKILL_GLOBAL_OP_UNLOCK:
+                rfkill_remove_epo_lock();
+                break;
+        case RFKILL_GLOBAL_OP_UNBLOCK:
+                rfkill_remove_epo_lock();
+                for (i = 0; i < RFKILL_TYPE_MAX; i++)
+                        rfkill_switch_all(i, RFKILL_STATE_UNBLOCKED);
+                break;
+        default:
+                /* memory corruption or bug, fail safely */
+                rfkill_epo();
+                WARN(1, "Unknown requested operation %d! "
+                        "rfkill Emergency Power Off activated\n",
+                        op);
+        }
+}
 
-        mutex_lock(&task->mutex);
+#ifdef RFKILL_NEED_SWSET
+static void __rfkill_handle_normal_op(const enum rfkill_type type,
+                        const bool sp, const bool s, const bool c)
+{
+        enum rfkill_state state;
 
-        rfkill_switch_all(task->type, task->desired_state);
+        if (sp)
+                state = (s) ? RFKILL_STATE_UNBLOCKED :
+                              RFKILL_STATE_SOFT_BLOCKED;
+        else
+                state = rfkill_get_global_state(type);
 
-        mutex_unlock(&task->mutex);
+        if (c)
+                state = rfkill_state_complement(state);
+
+        rfkill_switch_all(type, state);
 }
+#else
+static void __rfkill_handle_normal_op(const enum rfkill_type type,
+                        const bool c)
+{
+        enum rfkill_state state;
+
+        state = rfkill_get_global_state(type);
+        if (c)
+                state = rfkill_state_complement(state);
+
+        rfkill_switch_all(type, state);
+}
+#endif
 
-static void rfkill_task_epo_handler(struct work_struct *work)
+static void rfkill_task_handler(struct work_struct *work)
 {
-        rfkill_epo();
+        struct rfkill_task *task =
+                        container_of(work, struct rfkill_task, work);
+        bool doit = true;
+
+        mutex_lock(&task->mutex);
+
+        spin_lock_irq(&task->lock);
+        while (doit) {
+                if (task->global_op_pending) {
+                        enum rfkill_global_sched_op op = task->op;
+                        task->global_op_pending = false;
+                        memset(task->sw_pending, 0, sizeof(task->sw_pending));
+                        spin_unlock_irq(&task->lock);
+
+                        __rfkill_handle_global_op(op);
+
+                        /* make sure we do at least one pass with
+                         * !task->global_op_pending */
+                        spin_lock_irq(&task->lock);
+                        continue;
+                } else if (!rfkill_is_epo_lock_active()) {
+                        unsigned int i = 0;
+
+                        while (!task->global_op_pending &&
+                                                i < RFKILL_TYPE_MAX) {
+                                if (test_and_clear_bit(i, task->sw_pending)) {
+                                        bool c;
+#ifdef RFKILL_NEED_SWSET
+                                        bool sp, s;
+                                        sp = test_and_clear_bit(i,
+                                                        task->sw_setpending);
+                                        s = test_bit(i, task->sw_newstate);
+#endif
+                                        c = test_and_clear_bit(i,
+                                                        task->sw_togglestate);
+                                        spin_unlock_irq(&task->lock);
+
+#ifdef RFKILL_NEED_SWSET
+                                        __rfkill_handle_normal_op(i, sp, s, c);
+#else
+                                        __rfkill_handle_normal_op(i, c);
+#endif
+
+                                        spin_lock_irq(&task->lock);
+                                }
+                                i++;
+                        }
+                }
+                doit = task->global_op_pending;
+        }
+        spin_unlock_irq(&task->lock);
+
+        mutex_unlock(&task->mutex);
 }
 
-static DECLARE_WORK(epo_work, rfkill_task_epo_handler);
+static struct rfkill_task rfkill_task = {
+        .work = __WORK_INITIALIZER(rfkill_task.work,
+                                rfkill_task_handler),
+        .mutex = __MUTEX_INITIALIZER(rfkill_task.mutex),
+        .lock = __SPIN_LOCK_UNLOCKED(rfkill_task.lock),
+};
 
-static void rfkill_schedule_epo(void)
+static void rfkill_schedule_global_op(enum rfkill_global_sched_op op)
 {
-        schedule_work(&epo_work);
+        unsigned long flags;
+
+        spin_lock_irqsave(&rfkill_task.lock, flags);
+        rfkill_task.op = op;
+        rfkill_task.global_op_pending = true;
+        schedule_work(&rfkill_task.work);
+        spin_unlock_irqrestore(&rfkill_task.lock, flags);
 }
 
-static void rfkill_schedule_set(struct rfkill_task *task,
+#ifdef RFKILL_NEED_SWSET
+/* Use this if you need to add EV_SW SW_WLAN/WWAN/BLUETOOTH/etc handling */
+
+static void rfkill_schedule_set(enum rfkill_type type,
                                 enum rfkill_state desired_state)
 {
         unsigned long flags;
 
-        if (unlikely(work_pending(&epo_work)))
+        if (rfkill_is_epo_lock_active())
                 return;
 
-        spin_lock_irqsave(&task->lock, flags);
-
-        if (time_after(jiffies, task->last + msecs_to_jiffies(200))) {
-                task->desired_state = desired_state;
-                task->last = jiffies;
-                schedule_work(&task->work);
+        spin_lock_irqsave(&rfkill_task.lock, flags);
+        if (!rfkill_task.global_op_pending) {
+                set_bit(type, rfkill_task.sw_pending);
+                set_bit(type, rfkill_task.sw_setpending);
+                clear_bit(type, rfkill_task.sw_togglestate);
+                if (desired_state)
+                        set_bit(type,  rfkill_task.sw_newstate);
+                else
+                        clear_bit(type, rfkill_task.sw_newstate);
+                schedule_work(&rfkill_task.work);
         }
-
-        spin_unlock_irqrestore(&task->lock, flags);
+        spin_unlock_irqrestore(&rfkill_task.lock, flags);
 }
+#endif
 
-static void rfkill_schedule_toggle(struct rfkill_task *task)
+static void rfkill_schedule_toggle(enum rfkill_type type)
 {
         unsigned long flags;
 
-        if (unlikely(work_pending(&epo_work)))
+        if (rfkill_is_epo_lock_active())
                 return;
 
-        spin_lock_irqsave(&task->lock, flags);
-
-        if (time_after(jiffies, task->last + msecs_to_jiffies(200))) {
-                task->desired_state =
-                                rfkill_state_complement(task->desired_state);
-                task->last = jiffies;
-                schedule_work(&task->work);
+        spin_lock_irqsave(&rfkill_task.lock, flags);
+        if (!rfkill_task.global_op_pending) {
+                set_bit(type, rfkill_task.sw_pending);
+                change_bit(type, rfkill_task.sw_togglestate);
+                schedule_work(&rfkill_task.work);
         }
-
-        spin_unlock_irqrestore(&task->lock, flags);
+        spin_unlock_irqrestore(&rfkill_task.lock, flags);
 }
 
-#define DEFINE_RFKILL_TASK(n, t)                                \
-        struct rfkill_task n = {                                \
-                .work = __WORK_INITIALIZER(n.work,              \
-                                rfkill_task_handler),           \
-                .type = t,                                      \
-                .mutex = __MUTEX_INITIALIZER(n.mutex),          \
-                .lock = __SPIN_LOCK_UNLOCKED(n.lock),           \
-                .desired_state = RFKILL_STATE_UNBLOCKED,        \
-        }
-
-static DEFINE_RFKILL_TASK(rfkill_wlan, RFKILL_TYPE_WLAN);
-static DEFINE_RFKILL_TASK(rfkill_bt, RFKILL_TYPE_BLUETOOTH);
-static DEFINE_RFKILL_TASK(rfkill_uwb, RFKILL_TYPE_UWB);
-static DEFINE_RFKILL_TASK(rfkill_wimax, RFKILL_TYPE_WIMAX);
-static DEFINE_RFKILL_TASK(rfkill_wwan, RFKILL_TYPE_WWAN);
-
 static void rfkill_schedule_evsw_rfkillall(int state)
 {
-        /* EVERY radio type. state != 0 means radios ON */
-        /* handle EPO (emergency power off) through shortcut */
         if (state) {
-                rfkill_schedule_set(&rfkill_wwan,
-                                    RFKILL_STATE_UNBLOCKED);
-                rfkill_schedule_set(&rfkill_wimax,
-                                    RFKILL_STATE_UNBLOCKED);
-                rfkill_schedule_set(&rfkill_uwb,
-                                    RFKILL_STATE_UNBLOCKED);
-                rfkill_schedule_set(&rfkill_bt,
-                                    RFKILL_STATE_UNBLOCKED);
-                rfkill_schedule_set(&rfkill_wlan,
-                                    RFKILL_STATE_UNBLOCKED);
+                switch (rfkill_master_switch_mode) {
+                case RFKILL_INPUT_MASTER_UNBLOCKALL:
+                        rfkill_schedule_global_op(RFKILL_GLOBAL_OP_UNBLOCK);
+                        break;
+                case RFKILL_INPUT_MASTER_RESTORE:
+                        rfkill_schedule_global_op(RFKILL_GLOBAL_OP_RESTORE);
+                        break;
+                case RFKILL_INPUT_MASTER_DONOTHING:
+                        rfkill_schedule_global_op(RFKILL_GLOBAL_OP_UNLOCK);
+                        break;
+                default:
+                        /* memory corruption or driver bug! fail safely */
+                        rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
+                        WARN(1, "Unknown rfkill_master_switch_mode (%d), "
+                                "driver bug or memory corruption detected!\n",
+                                rfkill_master_switch_mode);
+                        break;
+                }
         } else
-                rfkill_schedule_epo();
+                rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
 }
 
 static void rfkill_event(struct input_handle *handle, unsigned int type,
                         unsigned int code, int data)
 {
         if (type == EV_KEY && data == 1) {
+                enum rfkill_type t;
+
                 switch (code) {
                 case KEY_WLAN:
-                        rfkill_schedule_toggle(&rfkill_wlan);
+                        t = RFKILL_TYPE_WLAN;
                         break;
                 case KEY_BLUETOOTH:
-                        rfkill_schedule_toggle(&rfkill_bt);
+                        t = RFKILL_TYPE_BLUETOOTH;
                         break;
                 case KEY_UWB:
-                        rfkill_schedule_toggle(&rfkill_uwb);
+                        t = RFKILL_TYPE_UWB;
                         break;
                 case KEY_WIMAX:
-                        rfkill_schedule_toggle(&rfkill_wimax);
+                        t = RFKILL_TYPE_WIMAX;
                         break;
                 default:
-                        break;
+                        return;
                 }
+                rfkill_schedule_toggle(t);
+                return;
         } else if (type == EV_SW) {
                 switch (code) {
                 case SW_RFKILL_ALL:
                         rfkill_schedule_evsw_rfkillall(data);
-                        break;
+                        return;
                 default:
-                        break;
+                        return;
                 }
         }
 }
@@ -256,11 +409,9 @@ static struct input_handler rfkill_handler = {
 
 static int __init rfkill_handler_init(void)
 {
-        unsigned long last_run = jiffies - msecs_to_jiffies(500);
-        rfkill_wlan.last = last_run;
-        rfkill_bt.last = last_run;
-        rfkill_uwb.last = last_run;
-        rfkill_wimax.last = last_run;
+        if (rfkill_master_switch_mode >= RFKILL_INPUT_MASTER_MAX)
+                return -EINVAL;
+
         return input_register_handler(&rfkill_handler);
 }
 
@@ -268,6 +419,7 @@ static void __exit rfkill_handler_exit(void)
 {
         input_unregister_handler(&rfkill_handler);
         flush_scheduled_work();
+        rfkill_remove_epo_lock();
 }
 
 module_init(rfkill_handler_init);
diff --git a/net/rfkill/rfkill-input.h b/net/rfkill/rfkill-input.h
index d1e03e85cbed..fe8df6b5b935 100644
--- a/net/rfkill/rfkill-input.h
+++ b/net/rfkill/rfkill-input.h
@@ -14,6 +14,8 @@
 void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state);
 void rfkill_epo(void);
 void rfkill_restore_states(void);
+void rfkill_remove_epo_lock(void);
+bool rfkill_is_epo_lock_active(void);
 enum rfkill_state rfkill_get_global_state(const enum rfkill_type type);
 
 #endif /* __RFKILL_INPUT_H */
diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c
index fdf87d2ab25e..e348eab756f3 100644
--- a/net/rfkill/rfkill.c
+++ b/net/rfkill/rfkill.c
@@ -51,6 +51,7 @@ struct rfkill_gsw_state {
 
 static struct rfkill_gsw_state rfkill_global_states[RFKILL_TYPE_MAX];
 static unsigned long rfkill_states_lockdflt[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
+static bool rfkill_epo_lock_active;
 
 static BLOCKING_NOTIFIER_HEAD(rfkill_notifier_list);
 
@@ -264,11 +265,14 @@ static void __rfkill_switch_all(const enum rfkill_type type,
  *
  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
  * Please refer to __rfkill_switch_all() for details.
+ *
+ * Does nothing if the EPO lock is active.
  */
 void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
 {
         mutex_lock(&rfkill_global_mutex);
-        __rfkill_switch_all(type, state);
+        if (!rfkill_epo_lock_active)
+                __rfkill_switch_all(type, state);
         mutex_unlock(&rfkill_global_mutex);
 }
 EXPORT_SYMBOL(rfkill_switch_all);
@@ -289,6 +293,7 @@ void rfkill_epo(void)
 
         mutex_lock(&rfkill_global_mutex);
 
+        rfkill_epo_lock_active = true;
         list_for_each_entry(rfkill, &rfkill_list, node) {
                 mutex_lock(&rfkill->mutex);
                 rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1);
@@ -317,6 +322,7 @@ void rfkill_restore_states(void)
 
         mutex_lock(&rfkill_global_mutex);
 
+        rfkill_epo_lock_active = false;
         for (i = 0; i < RFKILL_TYPE_MAX; i++)
                 __rfkill_switch_all(i, rfkill_global_states[i].default_state);
         mutex_unlock(&rfkill_global_mutex);
@@ -324,6 +330,35 @@ void rfkill_restore_states(void)
 EXPORT_SYMBOL_GPL(rfkill_restore_states);
 
 /**
+ * rfkill_remove_epo_lock - unlock state changes
+ *
+ * Used by rfkill-input manually unlock state changes, when
+ * the EPO switch is deactivated.
+ */
+void rfkill_remove_epo_lock(void)
+{
+        mutex_lock(&rfkill_global_mutex);
+        rfkill_epo_lock_active = false;
+        mutex_unlock(&rfkill_global_mutex);
+}
+EXPORT_SYMBOL_GPL(rfkill_remove_epo_lock);
+
+/**
+ * rfkill_is_epo_lock_active - returns true EPO is active
+ *
+ * Returns 0 (false) if there is NOT an active EPO contidion,
+ * and 1 (true) if there is an active EPO contition, which
+ * locks all radios in one of the BLOCKED states.
+ *
+ * Can be called in atomic context.
+ */
+bool rfkill_is_epo_lock_active(void)
+{
+        return rfkill_epo_lock_active;
+}
+EXPORT_SYMBOL_GPL(rfkill_is_epo_lock_active);
+
+/**
  * rfkill_get_global_state - returns global state for a type
  * @type: the type to get the global state of
  *
@@ -447,7 +482,12 @@ static ssize_t rfkill_state_store(struct device *dev,
         error = mutex_lock_killable(&rfkill->mutex);
         if (error)
                 return error;
-        error = rfkill_toggle_radio(rfkill, state, 0);
+
+        if (!rfkill_epo_lock_active)
+                error = rfkill_toggle_radio(rfkill, state, 0);
+        else
+                error = -EPERM;
+
         mutex_unlock(&rfkill->mutex);
 
         return error ? error : count;
@@ -491,7 +531,7 @@ static ssize_t rfkill_claim_store(struct device *dev,
                 return error;
 
         if (rfkill->user_claim != claim) {
-                if (!claim) {
+                if (!claim && !rfkill_epo_lock_active) {
                         mutex_lock(&rfkill->mutex);
                         rfkill_toggle_radio(rfkill,
                                         rfkill_global_states[rfkill->type].current_state,