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>

1 files changed, 34 insertions, 89 deletions

diff --git a/drivers/net/wireless/b43/rfkill.c b/drivers/net/wireless/b43/rfkill.c
index 9e1d00bc24d3..96047843cd56 100644
--- a/drivers/net/wireless/b43/rfkill.c
+++ b/drivers/net/wireless/b43/rfkill.c
@@ -45,12 +45,11 @@ static bool b43_is_hw_radio_enabled(struct b43_wldev *dev)
 }
 
 /* The poll callback for the hardware button. */
-static void b43_rfkill_poll(struct input_polled_dev *poll_dev)
+static void b43_rfkill_poll(struct rfkill *rfkill, void *data)
 {
-        struct b43_wldev *dev = poll_dev->private;
+        struct b43_wldev *dev = data;
         struct b43_wl *wl = dev->wl;
         bool enabled;
-        bool report_change = 0;
 
         mutex_lock(&wl->mutex);
         if (unlikely(b43_status(dev) < B43_STAT_INITIALIZED)) {
@@ -60,68 +59,55 @@ static void b43_rfkill_poll(struct input_polled_dev *poll_dev)
         enabled = b43_is_hw_radio_enabled(dev);
         if (unlikely(enabled != dev->radio_hw_enable)) {
                 dev->radio_hw_enable = enabled;
-                report_change = 1;
                 b43info(wl, "Radio hardware status changed to %s\n",
                         enabled ? "ENABLED" : "DISABLED");
+                enabled = !rfkill_set_hw_state(rfkill, !enabled);
+                if (enabled != dev->phy.radio_on)
+                        b43_software_rfkill(dev, !enabled);
         }
         mutex_unlock(&wl->mutex);
-
-        /* send the radio switch event to the system - note both a key press
-         * and a release are required */
-        if (unlikely(report_change)) {
-                input_report_key(poll_dev->input, KEY_WLAN, 1);
-                input_report_key(poll_dev->input, KEY_WLAN, 0);
-        }
 }
 
 /* Called when the RFKILL toggled in software. */
-static int b43_rfkill_soft_toggle(void *data, enum rfkill_state state)
+static int b43_rfkill_soft_set(void *data, bool blocked)
 {
         struct b43_wldev *dev = data;
         struct b43_wl *wl = dev->wl;
-        int err = -EBUSY;
+        int err = -EINVAL;
 
-        if (!wl->rfkill.registered)
-                return 0;
+        if (WARN_ON(!wl->rfkill.registered))
+                return -EINVAL;
 
         mutex_lock(&wl->mutex);
+
         if (b43_status(dev) < B43_STAT_INITIALIZED)
                 goto out_unlock;
+
+        if (!dev->radio_hw_enable)
+                goto out_unlock;
+
+        if (!blocked != dev->phy.radio_on)
+                b43_software_rfkill(dev, blocked);
         err = 0;
-        switch (state) {
-        case RFKILL_STATE_UNBLOCKED:
-                if (!dev->radio_hw_enable) {
-                        /* No luck. We can't toggle the hardware RF-kill
-                         * button from software. */
-                        err = -EBUSY;
-                        goto out_unlock;
-                }
-                if (!dev->phy.radio_on)
-                        b43_software_rfkill(dev, state);
-                break;
-        case RFKILL_STATE_SOFT_BLOCKED:
-                if (dev->phy.radio_on)
-                        b43_software_rfkill(dev, state);
-                break;
-        default:
-                b43warn(wl, "Received unexpected rfkill state %d.\n", state);
-                break;
-        }
 out_unlock:
         mutex_unlock(&wl->mutex);
-
         return err;
 }
 
-char *b43_rfkill_led_name(struct b43_wldev *dev)
+const char *b43_rfkill_led_name(struct b43_wldev *dev)
 {
         struct b43_rfkill *rfk = &(dev->wl->rfkill);
 
         if (!rfk->registered)
                 return NULL;
-        return rfkill_get_led_name(rfk->rfkill);
+        return rfkill_get_led_trigger_name(rfk->rfkill);
 }
 
+static const struct rfkill_ops b43_rfkill_ops = {
+        .set_block = b43_rfkill_soft_set,
+        .poll = b43_rfkill_poll,
+};
+
 void b43_rfkill_init(struct b43_wldev *dev)
 {
         struct b43_wl *wl = dev->wl;
@@ -130,65 +116,26 @@ void b43_rfkill_init(struct b43_wldev *dev)
 
         rfk->registered = 0;
 
-        rfk->rfkill = rfkill_allocate(dev->dev->dev, RFKILL_TYPE_WLAN);
-        if (!rfk->rfkill)
-                goto out_error;
         snprintf(rfk->name, sizeof(rfk->name),
                  "b43-%s", wiphy_name(wl->hw->wiphy));
-        rfk->rfkill->name = rfk->name;
-        rfk->rfkill->state = RFKILL_STATE_UNBLOCKED;
-        rfk->rfkill->data = dev;
-        rfk->rfkill->toggle_radio = b43_rfkill_soft_toggle;
-
-        rfk->poll_dev = input_allocate_polled_device();
-        if (!rfk->poll_dev) {
-                rfkill_free(rfk->rfkill);
-                goto err_freed_rfk;
-        }
-
-        rfk->poll_dev->private = dev;
-        rfk->poll_dev->poll = b43_rfkill_poll;
-        rfk->poll_dev->poll_interval = 1000; /* msecs */
 
-        rfk->poll_dev->input->name = rfk->name;
-        rfk->poll_dev->input->id.bustype = BUS_HOST;
-        rfk->poll_dev->input->id.vendor = dev->dev->bus->boardinfo.vendor;
-        rfk->poll_dev->input->evbit[0] = BIT(EV_KEY);
-        set_bit(KEY_WLAN, rfk->poll_dev->input->keybit);
+        rfk->rfkill = rfkill_alloc(rfk->name,
+                                   dev->dev->dev,
+                                   RFKILL_TYPE_WLAN,
+                                   &b43_rfkill_ops, dev);
+        if (!rfk->rfkill)
+                goto out_error;
 
         err = rfkill_register(rfk->rfkill);
         if (err)
-                goto err_free_polldev;
-
-#ifdef CONFIG_RFKILL_INPUT_MODULE
-        /* B43 RF-kill isn't useful without the rfkill-input subsystem.
-         * Try to load the module. */
-        err = request_module("rfkill-input");
-        if (err)
-                b43warn(wl, "Failed to load the rfkill-input module. "
-                        "The built-in radio LED will not work.\n");
-#endif /* CONFIG_RFKILL_INPUT */
-
-#if !defined(CONFIG_RFKILL_INPUT) && !defined(CONFIG_RFKILL_INPUT_MODULE)
-        b43warn(wl, "The rfkill-input subsystem is not available. "
-                "The built-in radio LED will not work.\n");
-#endif
-
-        err = input_register_polled_device(rfk->poll_dev);
-        if (err)
-                goto err_unreg_rfk;
+                goto err_free;
 
         rfk->registered = 1;
 
         return;
-err_unreg_rfk:
-        rfkill_unregister(rfk->rfkill);
-err_free_polldev:
-        input_free_polled_device(rfk->poll_dev);
-        rfk->poll_dev = NULL;
-err_freed_rfk:
-        rfk->rfkill = NULL;
-out_error:
+ err_free:
+        rfkill_destroy(rfk->rfkill);
+ out_error:
         rfk->registered = 0;
         b43warn(wl, "RF-kill button init failed\n");
 }
@@ -201,9 +148,7 @@ void b43_rfkill_exit(struct b43_wldev *dev)
                 return;
         rfk->registered = 0;
 
-        input_unregister_polled_device(rfk->poll_dev);
         rfkill_unregister(rfk->rfkill);
-        input_free_polled_device(rfk->poll_dev);
-        rfk->poll_dev = NULL;
+        rfkill_destroy(rfk->rfkill);
         rfk->rfkill = NULL;
 }