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>

2 files changed, 30 insertions, 44 deletions

diff --git a/drivers/net/wireless/iwlwifi/Kconfig b/drivers/net/wireless/iwlwifi/Kconfig
index 8304f6406a1..6fe259fcfb8 100644
--- a/drivers/net/wireless/iwlwifi/Kconfig
+++ b/drivers/net/wireless/iwlwifi/Kconfig
@@ -5,15 +5,14 @@ config IWLWIFI
 	select FW_LOADER
 	select MAC80211_LEDS if IWLWIFI_LEDS
 	select LEDS_CLASS if IWLWIFI_LEDS
-	select RFKILL if IWLWIFI_RFKILL
 
 config IWLWIFI_LEDS
 	bool "Enable LED support in iwlagn and iwl3945 drivers"
 	depends on IWLWIFI
 
 config IWLWIFI_RFKILL
-	bool "Enable RF kill support in iwlagn and iwl3945 drivers"
-	depends on IWLWIFI
+	def_bool y
+	depends on IWLWIFI && RFKILL
 
 config IWLWIFI_SPECTRUM_MEASUREMENT
 	bool "Enable Spectrum Measurement in iwlagn driver"
diff --git a/drivers/net/wireless/iwlwifi/iwl-rfkill.c b/drivers/net/wireless/iwlwifi/iwl-rfkill.c
index 65605ad44e4..13149936fd2 100644
--- a/drivers/net/wireless/iwlwifi/iwl-rfkill.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rfkill.c
@@ -36,42 +36,37 @@
 #include "iwl-core.h"
 
 /* software rf-kill from user */
-static int iwl_rfkill_soft_rf_kill(void *data, enum rfkill_state state)
+static int iwl_rfkill_soft_rf_kill(void *data, bool blocked)
 {
 	struct iwl_priv *priv = data;
-	int err = 0;
 
 	if (!priv->rfkill)
-		return 0;
+		return -EINVAL;
 
 	if (test_bit(STATUS_EXIT_PENDING, &priv->status))
 		return 0;
 
-	IWL_DEBUG_RF_KILL(priv, "we received soft RFKILL set to state %d\n", state);
+	IWL_DEBUG_RF_KILL(priv, "received soft RFKILL: block=%d\n", blocked);
+
 	mutex_lock(&priv->mutex);
 
-	switch (state) {
-	case RFKILL_STATE_UNBLOCKED:
-		if (iwl_is_rfkill_hw(priv)) {
-			err = -EBUSY;
-			goto out_unlock;
-		}
+	if (iwl_is_rfkill_hw(priv))
+		goto out_unlock;
+
+	if (!blocked)
 		iwl_radio_kill_sw_enable_radio(priv);
-		break;
-	case RFKILL_STATE_SOFT_BLOCKED:
+	else
 		iwl_radio_kill_sw_disable_radio(priv);
-		break;
-	default:
-		IWL_WARN(priv, "we received unexpected RFKILL state %d\n",
-			state);
-		break;
-	}
+
 out_unlock:
 	mutex_unlock(&priv->mutex);
-
-	return err;
+	return 0;
 }
 
+static const struct rfkill_ops iwl_rfkill_ops = {
+	.set_block = iwl_rfkill_soft_rf_kill,
+};
+
 int iwl_rfkill_init(struct iwl_priv *priv)
 {
 	struct device *device = wiphy_dev(priv->hw->wiphy);
@@ -80,21 +75,16 @@ int iwl_rfkill_init(struct iwl_priv *priv)
 	BUG_ON(device == NULL);
 
 	IWL_DEBUG_RF_KILL(priv, "Initializing RFKILL.\n");
-	priv->rfkill = rfkill_allocate(device, RFKILL_TYPE_WLAN);
+	priv->rfkill = rfkill_alloc(priv->cfg->name,
+				    device,
+				    RFKILL_TYPE_WLAN,
+				    &iwl_rfkill_ops, priv);
 	if (!priv->rfkill) {
 		IWL_ERR(priv, "Unable to allocate RFKILL device.\n");
 		ret = -ENOMEM;
 		goto error;
 	}
 
-	priv->rfkill->name = priv->cfg->name;
-	priv->rfkill->data = priv;
-	priv->rfkill->state = RFKILL_STATE_UNBLOCKED;
-	priv->rfkill->toggle_radio = iwl_rfkill_soft_rf_kill;
-
-	priv->rfkill->dev.class->suspend = NULL;
-	priv->rfkill->dev.class->resume = NULL;
-
 	ret = rfkill_register(priv->rfkill);
 	if (ret) {
 		IWL_ERR(priv, "Unable to register RFKILL: %d\n", ret);
@@ -102,11 +92,10 @@ int iwl_rfkill_init(struct iwl_priv *priv)
 	}
 
 	IWL_DEBUG_RF_KILL(priv, "RFKILL initialization complete.\n");
-	return ret;
+	return 0;
 
 free_rfkill:
-	if (priv->rfkill != NULL)
-		rfkill_free(priv->rfkill);
+	rfkill_destroy(priv->rfkill);
 	priv->rfkill = NULL;
 
 error:
@@ -118,8 +107,10 @@ EXPORT_SYMBOL(iwl_rfkill_init);
 void iwl_rfkill_unregister(struct iwl_priv *priv)
 {
 
-	if (priv->rfkill)
+	if (priv->rfkill) {
 		rfkill_unregister(priv->rfkill);
+		rfkill_destroy(priv->rfkill);
+	}
 
 	priv->rfkill = NULL;
 }
@@ -131,14 +122,10 @@ void iwl_rfkill_set_hw_state(struct iwl_priv *priv)
 	if (!priv->rfkill)
 		return;
 
-	if (iwl_is_rfkill_hw(priv)) {
-		rfkill_force_state(priv->rfkill, RFKILL_STATE_HARD_BLOCKED);
-		return;
-	}
-
-	if (!iwl_is_rfkill_sw(priv))
-		rfkill_force_state(priv->rfkill, RFKILL_STATE_UNBLOCKED);
+	if (rfkill_set_hw_state(priv->rfkill,
+				!!iwl_is_rfkill_hw(priv)))
+		iwl_radio_kill_sw_disable_radio(priv);
 	else
-		rfkill_force_state(priv->rfkill, RFKILL_STATE_SOFT_BLOCKED);
+		iwl_radio_kill_sw_enable_radio(priv);
 }
 EXPORT_SYMBOL(iwl_rfkill_set_hw_state);