rfkill: rewrite

This patch completely rewrites the rfkill core to address
the following deficiencies:

 * all rfkill drivers need to implement polling where necessary
   rather than having one central implementation

 * updating the rfkill state cannot be done from arbitrary
   contexts, forcing drivers to use schedule_work and requiring
   lots of code

 * rfkill drivers need to keep track of soft/hard blocked
   internally -- the core should do this

 * the rfkill API has many unexpected quirks, for example being
   asymmetric wrt. alloc/free and register/unregister

 * rfkill can call back into a driver from within a function the
   driver called -- this is prone to deadlocks and generally
   should be avoided

 * rfkill-input pointlessly is a separate module

 * drivers need to #ifdef rfkill functions (unless they want to
   depend on or select RFKILL) -- rfkill should provide inlines
   that do nothing if it isn't compiled in

 * the rfkill structure is not opaque -- drivers need to initialise
   it correctly (lots of sanity checking code required) -- instead
   force drivers to pass the right variables to rfkill_alloc()

 * the documentation is hard to read because it always assumes the
   reader is completely clueless and contains way TOO MANY CAPS

 * the rfkill code needlessly uses a lot of locks and atomic
   operations in locked sections

 * fix LED trigger to actually change the LED when the radio state
   changes -- this wasn't done before

Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 30 insertions, 107 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 796a3adffea0..515880aa2116 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -460,12 +460,9 @@ struct ath_led {
         bool registered;
 };
 
-/* Rfkill */
-#define ATH_RFKILL_POLL_INTERVAL        2000 /* msecs */
-
 struct ath_rfkill {
         struct rfkill *rfkill;
-        struct delayed_work rfkill_poll;
+        struct rfkill_ops ops;
         char rfkill_name[32];
 };
 
@@ -509,8 +506,6 @@ struct ath_rfkill {
 #define SC_OP_RXFLUSH           BIT(7)
 #define SC_OP_LED_ASSOCIATED    BIT(8)
 #define SC_OP_RFKILL_REGISTERED BIT(9)
-#define SC_OP_RFKILL_SW_BLOCKED BIT(10)
-#define SC_OP_RFKILL_HW_BLOCKED BIT(11)
 #define SC_OP_WAIT_FOR_BEACON   BIT(12)
 #define SC_OP_LED_ON            BIT(13)
 #define SC_OP_SCANNING          BIT(14)
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 61da08a1648c..f7baa406918b 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1192,120 +1192,69 @@ static bool ath_is_rfkill_set(struct ath_softc *sc)
                                   ah->rfkill_polarity;
 }
 
-/* h/w rfkill poll function */
-static void ath_rfkill_poll(struct work_struct *work)
+/* s/w rfkill handlers */
+static int ath_rfkill_set_block(void *data, bool blocked)
 {
-        struct ath_softc *sc = container_of(work, struct ath_softc,
-                                            rf_kill.rfkill_poll.work);
-        bool radio_on;
-
-        if (sc->sc_flags & SC_OP_INVALID)
-                return;
-
-        radio_on = !ath_is_rfkill_set(sc);
-
-        /*
-         * enable/disable radio only when there is a
-         * state change in RF switch
-         */
-        if (radio_on == !!(sc->sc_flags & SC_OP_RFKILL_HW_BLOCKED)) {
-                enum rfkill_state state;
-
-                if (sc->sc_flags & SC_OP_RFKILL_SW_BLOCKED) {
-                        state = radio_on ? RFKILL_STATE_SOFT_BLOCKED
-                                : RFKILL_STATE_HARD_BLOCKED;
-                } else if (radio_on) {
-                        ath_radio_enable(sc);
-                        state = RFKILL_STATE_UNBLOCKED;
-                } else {
-                        ath_radio_disable(sc);
-                        state = RFKILL_STATE_HARD_BLOCKED;
-                }
-
-                if (state == RFKILL_STATE_HARD_BLOCKED)
-                        sc->sc_flags |= SC_OP_RFKILL_HW_BLOCKED;
-                else
-                        sc->sc_flags &= ~SC_OP_RFKILL_HW_BLOCKED;
+        struct ath_softc *sc = data;
 
-                rfkill_force_state(sc->rf_kill.rfkill, state);
-        }
+        if (blocked)
+                ath_radio_disable(sc);
+        else
+                ath_radio_enable(sc);
 
-        queue_delayed_work(sc->hw->workqueue, &sc->rf_kill.rfkill_poll,
-                           msecs_to_jiffies(ATH_RFKILL_POLL_INTERVAL));
+        return 0;
 }
 
-/* s/w rfkill handler */
-static int ath_sw_toggle_radio(void *data, enum rfkill_state state)
+static void ath_rfkill_poll_state(struct rfkill *rfkill, void *data)
 {
         struct ath_softc *sc = data;
+        bool blocked = !!ath_is_rfkill_set(sc);
 
-        switch (state) {
-        case RFKILL_STATE_SOFT_BLOCKED:
-                if (!(sc->sc_flags & (SC_OP_RFKILL_HW_BLOCKED |
-                    SC_OP_RFKILL_SW_BLOCKED)))
-                        ath_radio_disable(sc);
-                sc->sc_flags |= SC_OP_RFKILL_SW_BLOCKED;
-                return 0;
-        case RFKILL_STATE_UNBLOCKED:
-                if ((sc->sc_flags & SC_OP_RFKILL_SW_BLOCKED)) {
-                        sc->sc_flags &= ~SC_OP_RFKILL_SW_BLOCKED;
-                        if (sc->sc_flags & SC_OP_RFKILL_HW_BLOCKED) {
-                                DPRINTF(sc, ATH_DBG_FATAL, "Can't turn on the"
-                                        "radio as it is disabled by h/w\n");
-                                return -EPERM;
-                        }
-                        ath_radio_enable(sc);
-                }
-                return 0;
-        default:
-                return -EINVAL;
-        }
+        if (rfkill_set_hw_state(rfkill, blocked))
+                ath_radio_disable(sc);
+        else
+                ath_radio_enable(sc);
 }
 
 /* Init s/w rfkill */
 static int ath_init_sw_rfkill(struct ath_softc *sc)
 {
-        sc->rf_kill.rfkill = rfkill_allocate(wiphy_dev(sc->hw->wiphy),
-                                             RFKILL_TYPE_WLAN);
+        sc->rf_kill.ops.set_block = ath_rfkill_set_block;
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
+                sc->rf_kill.ops.poll = ath_rfkill_poll_state;
+
+        snprintf(sc->rf_kill.rfkill_name, sizeof(sc->rf_kill.rfkill_name),
+                "ath9k-%s::rfkill", wiphy_name(sc->hw->wiphy));
+
+        sc->rf_kill.rfkill = rfkill_alloc(sc->rf_kill.rfkill_name,
+                                          wiphy_dev(sc->hw->wiphy),
+                                          RFKILL_TYPE_WLAN,
+                                          &sc->rf_kill.ops, sc);
         if (!sc->rf_kill.rfkill) {
                 DPRINTF(sc, ATH_DBG_FATAL, "Failed to allocate rfkill\n");
                 return -ENOMEM;
         }
 
-        snprintf(sc->rf_kill.rfkill_name, sizeof(sc->rf_kill.rfkill_name),
-                "ath9k-%s::rfkill", wiphy_name(sc->hw->wiphy));
-        sc->rf_kill.rfkill->name = sc->rf_kill.rfkill_name;
-        sc->rf_kill.rfkill->data = sc;
-        sc->rf_kill.rfkill->toggle_radio = ath_sw_toggle_radio;
-        sc->rf_kill.rfkill->state = RFKILL_STATE_UNBLOCKED;
-
         return 0;
 }
 
 /* Deinitialize rfkill */
 static void ath_deinit_rfkill(struct ath_softc *sc)
 {
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                cancel_delayed_work_sync(&sc->rf_kill.rfkill_poll);
-
         if (sc->sc_flags & SC_OP_RFKILL_REGISTERED) {
                 rfkill_unregister(sc->rf_kill.rfkill);
+                rfkill_destroy(sc->rf_kill.rfkill);
                 sc->sc_flags &= ~SC_OP_RFKILL_REGISTERED;
-                sc->rf_kill.rfkill = NULL;
         }
 }
 
 static int ath_start_rfkill_poll(struct ath_softc *sc)
 {
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                queue_delayed_work(sc->hw->workqueue,
-                                   &sc->rf_kill.rfkill_poll, 0);
-
         if (!(sc->sc_flags & SC_OP_RFKILL_REGISTERED)) {
                 if (rfkill_register(sc->rf_kill.rfkill)) {
                         DPRINTF(sc, ATH_DBG_FATAL,
                                 "Unable to register rfkill\n");
-                        rfkill_free(sc->rf_kill.rfkill);
+                        rfkill_destroy(sc->rf_kill.rfkill);
 
                         /* Deinitialize the device */
                         ath_cleanup(sc);
@@ -1678,10 +1627,6 @@ int ath_attach(u16 devid, struct ath_softc *sc)
                 goto error_attach;
 
 #if defined(CONFIG_RFKILL) || defined(CONFIG_RFKILL_MODULE)
-        /* Initialze h/w Rfkill */
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                INIT_DELAYED_WORK(&sc->rf_kill.rfkill_poll, ath_rfkill_poll);
-
         /* Initialize s/w rfkill */
         error = ath_init_sw_rfkill(sc);
         if (error)
@@ -2214,10 +2159,8 @@ static void ath9k_stop(struct ieee80211_hw *hw)
         } else
                 sc->rx.rxlink = NULL;
 
-#if defined(CONFIG_RFKILL) || defined(CONFIG_RFKILL_MODULE)
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                cancel_delayed_work_sync(&sc->rf_kill.rfkill_poll);
-#endif
+        rfkill_pause_polling(sc->rf_kill.rfkill);
+
         /* disable HAL and put h/w to sleep */
         ath9k_hw_disable(sc->sc_ah);
         ath9k_hw_configpcipowersave(sc->sc_ah, 1);
diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c
index 168411d322a2..ccdf20a2e9be 100644
--- a/drivers/net/wireless/ath/ath9k/pci.c
+++ b/drivers/net/wireless/ath/ath9k/pci.c
@@ -227,11 +227,6 @@ static int ath_pci_suspend(struct pci_dev *pdev, pm_message_t state)
 
         ath9k_hw_set_gpio(sc->sc_ah, ATH_LED_PIN, 1);
 
-#if defined(CONFIG_RFKILL) || defined(CONFIG_RFKILL_MODULE)
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                cancel_delayed_work_sync(&sc->rf_kill.rfkill_poll);
-#endif
-
         pci_save_state(pdev);
         pci_disable_device(pdev);
         pci_set_power_state(pdev, PCI_D3hot);
@@ -256,16 +251,6 @@ static int ath_pci_resume(struct pci_dev *pdev)
                             AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
         ath9k_hw_set_gpio(sc->sc_ah, ATH_LED_PIN, 1);
 
-#if defined(CONFIG_RFKILL) || defined(CONFIG_RFKILL_MODULE)
-        /*
-         * check the h/w rfkill state on resume
-         * and start the rfkill poll timer
-         */
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_RFSILENT)
-                queue_delayed_work(sc->hw->workqueue,
-                                   &sc->rf_kill.rfkill_poll, 0);
-#endif
-
         return 0;
 }