3 files changed, 336 insertions, 84 deletions

diff --git a/net/rfkill/rfkill-input.c b/net/rfkill/rfkill-input.c
index bfdade72e066..84efde97c5a7 100644
--- a/net/rfkill/rfkill-input.c
+++ b/net/rfkill/rfkill-input.c
@@ -24,138 +24,318 @@ 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 */
+};
+
+/* Delay (in ms) between consecutive switch ops */
+#define RFKILL_OPS_DELAY 200
+
+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 */
+        struct delayed_work dwork;
+
+        /* 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;
+
+        /* last time it was scheduled */
+        unsigned long last_scheduled;
 };
 
+static void __rfkill_handle_global_op(enum rfkill_global_sched_op op)
+{
+        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);
+        }
+}
+
+#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;
+
+        if (sp)
+                state = (s) ? RFKILL_STATE_UNBLOCKED :
+                              RFKILL_STATE_SOFT_BLOCKED;
+        else
+                state = rfkill_get_global_state(type);
+
+        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_handler(struct work_struct *work)
 {
-        struct rfkill_task *task = container_of(work, struct rfkill_task, work);
+        struct rfkill_task *task = container_of(work,
+                                        struct rfkill_task, dwork.work);
+        bool doit = true;
 
         mutex_lock(&task->mutex);
 
-        rfkill_switch_all(task->type, task->desired_state);
+        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 void rfkill_task_epo_handler(struct work_struct *work)
+static struct rfkill_task rfkill_task = {
+        .dwork = __DELAYED_WORK_INITIALIZER(rfkill_task.dwork,
+                                rfkill_task_handler),
+        .mutex = __MUTEX_INITIALIZER(rfkill_task.mutex),
+        .lock = __SPIN_LOCK_UNLOCKED(rfkill_task.lock),
+};
+
+static unsigned long rfkill_ratelimit(const unsigned long last)
 {
-        rfkill_epo();
+        const unsigned long delay = msecs_to_jiffies(RFKILL_OPS_DELAY);
+        return (time_after(jiffies, last + delay)) ? 0 : delay;
 }
 
-static DECLARE_WORK(epo_work, rfkill_task_epo_handler);
+static void rfkill_schedule_ratelimited(void)
+{
+        if (!delayed_work_pending(&rfkill_task.dwork)) {
+                schedule_delayed_work(&rfkill_task.dwork,
+                                rfkill_ratelimit(rfkill_task.last_scheduled));
+                rfkill_task.last_scheduled = jiffies;
+        }
+}
 
-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;
+        if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) {
+                /* bypass the limiter for EPO */
+                cancel_delayed_work(&rfkill_task.dwork);
+                schedule_delayed_work(&rfkill_task.dwork, 0);
+                rfkill_task.last_scheduled = jiffies;
+        } else
+                rfkill_schedule_ratelimited();
+        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);
+                rfkill_schedule_ratelimited();
         }
-
-        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);
+                rfkill_schedule_ratelimited();
         }
-
-        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;
                 }
         }
 }
@@ -256,18 +436,23 @@ 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;
+
+        /*
+         * The penalty to not doing this is a possible RFKILL_OPS_DELAY delay
+         * at the first use.  Acceptable, but if we can avoid it, why not?
+         */
+        rfkill_task.last_scheduled =
+                        jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1;
         return input_register_handler(&rfkill_handler);
 }
 
 static void __exit rfkill_handler_exit(void)
 {
         input_unregister_handler(&rfkill_handler);
-        flush_scheduled_work();
+        cancel_delayed_work_sync(&rfkill_task.dwork);
+        rfkill_remove_epo_lock();
 }
 
 module_init(rfkill_handler_init);
diff --git a/net/rfkill/rfkill-input.h b/net/rfkill/rfkill-input.h
index bbfa646157c6..fe8df6b5b935 100644
--- a/net/rfkill/rfkill-input.h
+++ b/net/rfkill/rfkill-input.h
@@ -14,5 +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 25ba3bd57e66..69f3a3b4dd61 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 +330,48 @@ 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
+ *
+ * Returns the current global state for a given wireless
+ * device type.
+ */
+enum rfkill_state rfkill_get_global_state(const enum rfkill_type type)
+{
+        return rfkill_global_states[type].current_state;
+}
+EXPORT_SYMBOL_GPL(rfkill_get_global_state);
+
+/**
  * rfkill_force_state - Force the internal rfkill radio state
  * @rfkill: pointer to the rfkill class to modify.
  * @state: the current radio state the class should be forced to.
@@ -431,9 +479,15 @@ static ssize_t rfkill_state_store(struct device *dev,
             state != RFKILL_STATE_SOFT_BLOCKED)
                 return -EINVAL;
 
-        if (mutex_lock_interruptible(&rfkill->mutex))
-                return -ERESTARTSYS;
-        error = rfkill_toggle_radio(rfkill, state, 0);
+        error = mutex_lock_killable(&rfkill->mutex);
+        if (error)
+                return error;
+
+        if (!rfkill_epo_lock_active)
+                error = rfkill_toggle_radio(rfkill, state, 0);
+        else
+                error = -EPERM;
+
         mutex_unlock(&rfkill->mutex);
 
         return error ? error : count;
@@ -472,12 +526,12 @@ static ssize_t rfkill_claim_store(struct device *dev,
          * Take the global lock to make sure the kernel is not in
          * the middle of rfkill_switch_all
          */
-        error = mutex_lock_interruptible(&rfkill_global_mutex);
+        error = mutex_lock_killable(&rfkill_global_mutex);
         if (error)
                 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,
@@ -527,8 +581,17 @@ static int rfkill_resume(struct device *dev)
 
                 dev->power.power_state.event = PM_EVENT_ON;
 
-                /* restore radio state AND notify everybody */
-                rfkill_toggle_radio(rfkill, rfkill->state, 1);
+                /*
+                 * If we are under EPO, kick transmitter offline,
+                 * otherwise restore to pre-suspend state.
+                 *
+                 * Issue a notification in any case
+                 */
+                rfkill_toggle_radio(rfkill,
+                                rfkill_epo_lock_active ?
+                                        RFKILL_STATE_SOFT_BLOCKED :
+                                        rfkill->state,
+                                1);
 
                 mutex_unlock(&rfkill->mutex);
         }
@@ -833,6 +896,7 @@ int rfkill_set_default(enum rfkill_type type, enum rfkill_state state)
 
         if (!test_and_set_bit(type, rfkill_states_lockdflt)) {
                 rfkill_global_states[type].default_state = state;
+                rfkill_global_states[type].current_state = state;
                 error = 0;
         } else
                 error = -EPERM;