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, 39 insertions, 84 deletions

diff --git a/drivers/net/wireless/b43legacy/rfkill.c b/drivers/net/wireless/b43legacy/rfkill.c
index 4b0c7d27a51f..c6230a64505a 100644
--- a/drivers/net/wireless/b43legacy/rfkill.c
+++ b/drivers/net/wireless/b43legacy/rfkill.c
@@ -45,12 +45,11 @@ static bool b43legacy_is_hw_radio_enabled(struct b43legacy_wldev *dev)
 }
 
 /* The poll callback for the hardware button. */
-static void b43legacy_rfkill_poll(struct input_polled_dev *poll_dev)
+static void b43legacy_rfkill_poll(struct rfkill *rfkill, void *data)
 {
-	struct b43legacy_wldev *dev = poll_dev->private;
+	struct b43legacy_wldev *dev = data;
 	struct b43legacy_wl *wl = dev->wl;
 	bool enabled;
-	bool report_change = 0;
 
 	mutex_lock(&wl->mutex);
 	if (unlikely(b43legacy_status(dev) < B43legacy_STAT_INITIALIZED)) {
@@ -60,71 +59,64 @@ static void b43legacy_rfkill_poll(struct input_polled_dev *poll_dev)
 	enabled = b43legacy_is_hw_radio_enabled(dev);
 	if (unlikely(enabled != dev->radio_hw_enable)) {
 		dev->radio_hw_enable = enabled;
-		report_change = 1;
 		b43legacyinfo(wl, "Radio hardware status changed to %s\n",
 			enabled ? "ENABLED" : "DISABLED");
+		enabled = !rfkill_set_hw_state(rfkill, !enabled);
+		if (enabled != dev->phy.radio_on) {
+			if (enabled)
+				b43legacy_radio_turn_on(dev);
+			else
+				b43legacy_radio_turn_off(dev, 0);
+		}
 	}
 	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.
  * This is called without locking. */
-static int b43legacy_rfkill_soft_toggle(void *data, enum rfkill_state state)
+static int b43legacy_rfkill_soft_set(void *data, bool blocked)
 {
 	struct b43legacy_wldev *dev = data;
 	struct b43legacy_wl *wl = dev->wl;
-	int err = -EBUSY;
+	int ret = -EINVAL;
 
 	if (!wl->rfkill.registered)
-		return 0;
+		return -EINVAL;
 
 	mutex_lock(&wl->mutex);
 	if (b43legacy_status(dev) < B43legacy_STAT_INITIALIZED)
 		goto out_unlock;
-	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)
+
+	if (!dev->radio_hw_enable)
+		goto out_unlock;
+
+	if (!blocked != dev->phy.radio_on) {
+		if (!blocked)
 			b43legacy_radio_turn_on(dev);
-		break;
-	case RFKILL_STATE_SOFT_BLOCKED:
-		if (dev->phy.radio_on)
+		else
 			b43legacy_radio_turn_off(dev, 0);
-		break;
-	default:
-		b43legacywarn(wl, "Received unexpected rfkill state %d.\n",
-			      state);
-		break;
 	}
+	ret = 0;
 
 out_unlock:
 	mutex_unlock(&wl->mutex);
-
-	return err;
+	return ret;
 }
 
-char *b43legacy_rfkill_led_name(struct b43legacy_wldev *dev)
+const char *b43legacy_rfkill_led_name(struct b43legacy_wldev *dev)
 {
 	struct b43legacy_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 b43legacy_rfkill_ops = {
+	.set_block = b43legacy_rfkill_soft_set,
+	.poll = b43legacy_rfkill_poll,
+};
+
 void b43legacy_rfkill_init(struct b43legacy_wldev *dev)
 {
 	struct b43legacy_wl *wl = dev->wl;
@@ -133,60 +125,25 @@ void b43legacy_rfkill_init(struct b43legacy_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),
 		 "b43legacy-%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 = b43legacy_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 = b43legacy_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,
+				   &b43legacy_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
-	/* B43legacy RF-kill isn't useful without the rfkill-input subsystem.
-	 * Try to load the module. */
-	err = request_module("rfkill-input");
-	if (err)
-		b43legacywarn(wl, "Failed to load the rfkill-input module."
-			"The built-in radio LED will not work.\n");
-#endif /* CONFIG_RFKILL_INPUT */
-
-	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;
 	b43legacywarn(wl, "RF-kill button init failed\n");
 }
@@ -199,10 +156,8 @@ void b43legacy_rfkill_exit(struct b43legacy_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;
 }