iwlwifi: fix problem when rf_killswitch change during suspend/resume

After we delay device initialization until interface up, there are more
conditions for the hardware rf_kill switch states during suspend and
resume. For example, before suspend we can have interface up or down,
rf_kill enable or disable; before resume we can have rf_kill enable or
disable. So there are totally 2^3 = 8 conditions to handle. This patch
addressed this problem and makes sure every condition works correctly.

This patch also merges the device suspend and resume handlers with the
mac_start and mac_stop code since they are basically doing the same
thing.

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 44 insertions, 89 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl4965-base.c b/drivers/net/wireless/iwlwifi/iwl4965-base.c
index 98f09e6e9f8c..811e41b7f664 100644
--- a/drivers/net/wireless/iwlwifi/iwl4965-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl4965-base.c
@@ -6761,7 +6761,6 @@ static void iwl4965_down(struct iwl4965_priv *priv)
 static int __iwl4965_up(struct iwl4965_priv *priv)
 {
         int rc, i;
-        u32 hw_rf_kill = 0;
 
         if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
                 IWL_WARNING("Exit pending; will not bring the NIC up\n");
@@ -6771,7 +6770,19 @@ static int __iwl4965_up(struct iwl4965_priv *priv)
         if (test_bit(STATUS_RF_KILL_SW, &priv->status)) {
                 IWL_WARNING("Radio disabled by SW RF kill (module "
                             "parameter)\n");
-                return 0;
+                return -ENODEV;
+        }
+
+        /* If platform's RF_KILL switch is NOT set to KILL */
+        if (iwl4965_read32(priv, CSR_GP_CNTRL) &
+                                CSR_GP_CNTRL_REG_FLAG_HW_RF_KILL_SW)
+                clear_bit(STATUS_RF_KILL_HW, &priv->status);
+        else {
+                set_bit(STATUS_RF_KILL_HW, &priv->status);
+                if (!test_bit(STATUS_IN_SUSPEND, &priv->status)) {
+                        IWL_WARNING("Radio disabled by HW RF Kill switch\n");
+                        return -ENODEV;
+                }
         }
 
         if (!priv->ucode_data_backup.v_addr || !priv->ucode_data.v_addr) {
@@ -6806,17 +6817,9 @@ static int __iwl4965_up(struct iwl4965_priv *priv)
         memcpy(priv->ucode_data_backup.v_addr, priv->ucode_data.v_addr,
                priv->ucode_data.len);
 
-        /* If platform's RF_KILL switch is set to KILL,
-         * wait for BIT_INT_RF_KILL interrupt before loading uCode
-         * and getting things started */
-        if (!(iwl4965_read32(priv, CSR_GP_CNTRL) &
-                                CSR_GP_CNTRL_REG_FLAG_HW_RF_KILL_SW))
-                hw_rf_kill = 1;
-
-        if (test_bit(STATUS_RF_KILL_HW, &priv->status) || hw_rf_kill) {
-                IWL_WARNING("Radio disabled by HW RF Kill switch\n");
+        /* We return success when we resume from suspend and rf_kill is on. */
+        if (test_bit(STATUS_RF_KILL_HW, &priv->status))
                 return 0;
-        }
 
         for (i = 0; i < MAX_HW_RESTARTS; i++) {
 
@@ -7379,12 +7382,18 @@ static int iwl4965_mac_start(struct ieee80211_hw *hw)
                 }
         }
 
-        IWL_DEBUG_INFO("Start UP work.\n");
-        __iwl4965_up(priv);
+        ret = __iwl4965_up(priv);
 
-        priv->is_open = 1;
         mutex_unlock(&priv->mutex);
 
+        if (ret)
+                goto out_release_irq;
+
+        IWL_DEBUG_INFO("Start UP work done.\n");
+
+        if (test_bit(STATUS_IN_SUSPEND, &priv->status))
+                return 0;
+
         /* Wait for START_ALIVE from ucode. Otherwise callbacks from
          * mac80211 will not be run successfully. */
         ret = wait_event_interruptible_timeout(priv->wait_command_queue,
@@ -7399,6 +7408,7 @@ static int iwl4965_mac_start(struct ieee80211_hw *hw)
                 }
         }
 
+        priv->is_open = 1;
         IWL_DEBUG_MAC80211("leave\n");
         return 0;
 
@@ -7406,6 +7416,9 @@ out_release_irq:
         free_irq(priv->pci_dev->irq, priv);
 out_disable_msi:
         pci_disable_msi(priv->pci_dev);
+        pci_disable_device(priv->pci_dev);
+        priv->is_open = 0;
+        IWL_DEBUG_MAC80211("leave - failed\n");
         return ret;
 }
 
@@ -7415,12 +7428,17 @@ static void iwl4965_mac_stop(struct ieee80211_hw *hw)
 
         IWL_DEBUG_MAC80211("enter\n");
 
-        /* stop mac, cancel any scan request and clear
-         * RXON_FILTER_ASSOC_MSK BIT
-         */
+        if (!priv->is_open) {
+                IWL_DEBUG_MAC80211("leave - skip\n");
+                return;
+        }
+
         priv->is_open = 0;
 
         if (iwl4965_is_ready_rf(priv)) {
+                /* stop mac, cancel any scan request and clear
+                 * RXON_FILTER_ASSOC_MSK BIT
+                 */
                 mutex_lock(&priv->mutex);
                 iwl4965_scan_cancel_timeout(priv, 100);
                 cancel_delayed_work(&priv->post_associate);
@@ -8152,7 +8170,6 @@ static void iwl4965_mac_reset_tsf(struct ieee80211_hw *hw)
         mutex_unlock(&priv->mutex);
 
         IWL_DEBUG_MAC80211("leave\n");
-
 }
 
 static int iwl4965_mac_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
@@ -9327,89 +9344,27 @@ static int iwl4965_pci_suspend(struct pci_dev *pdev, pm_message_t state)
 {
         struct iwl4965_priv *priv = pci_get_drvdata(pdev);
 
-        set_bit(STATUS_IN_SUSPEND, &priv->status);
-
-        /* Take down the device; powers it off, etc. */
-        iwl4965_down(priv);
-
-        if (priv->mac80211_registered)
-                ieee80211_stop_queues(priv->hw);
+        if (priv->is_open) {
+                set_bit(STATUS_IN_SUSPEND, &priv->status);
+                iwl4965_mac_stop(priv->hw);
+                priv->is_open = 1;
+        }
 
-        pci_save_state(pdev);
-        pci_disable_device(pdev);
         pci_set_power_state(pdev, PCI_D3hot);
 
         return 0;
 }
 
-static void iwl4965_resume(struct iwl4965_priv *priv)
-{
-        unsigned long flags;
-
-        /* The following it a temporary work around due to the
-         * suspend / resume not fully initializing the NIC correctly.
-         * Without all of the following, resume will not attempt to take
-         * down the NIC (it shouldn't really need to) and will just try
-         * and bring the NIC back up.  However that fails during the
-         * ucode verification process.  This then causes iwl4965_down to be
-         * called *after* iwl4965_hw_nic_init() has succeeded -- which
-         * then lets the next init sequence succeed.  So, we've
-         * replicated all of that NIC init code here... */
-
-        iwl4965_write32(priv, CSR_INT, 0xFFFFFFFF);
-
-        iwl4965_hw_nic_init(priv);
-
-        iwl4965_write32(priv, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
-        iwl4965_write32(priv, CSR_UCODE_DRV_GP1_CLR,
-                    CSR_UCODE_DRV_GP1_BIT_CMD_BLOCKED);
-        iwl4965_write32(priv, CSR_INT, 0xFFFFFFFF);
-        iwl4965_write32(priv, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
-        iwl4965_write32(priv, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
-
-        /* tell the device to stop sending interrupts */
-        iwl4965_disable_interrupts(priv);
-
-        spin_lock_irqsave(&priv->lock, flags);
-        iwl4965_clear_bit(priv, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
-
-        if (!iwl4965_grab_nic_access(priv)) {
-                iwl4965_write_prph(priv, APMG_CLK_DIS_REG,
-                                APMG_CLK_VAL_DMA_CLK_RQT);
-                iwl4965_release_nic_access(priv);
-        }
-        spin_unlock_irqrestore(&priv->lock, flags);
-
-        udelay(5);
-
-        iwl4965_hw_nic_reset(priv);
-
-        /* Bring the device back up */
-        clear_bit(STATUS_IN_SUSPEND, &priv->status);
-        queue_work(priv->workqueue, &priv->up);
-}
-
 static int iwl4965_pci_resume(struct pci_dev *pdev)
 {
         struct iwl4965_priv *priv = pci_get_drvdata(pdev);
-        int err;
-
-        printk(KERN_INFO "Coming out of suspend...\n");
 
         pci_set_power_state(pdev, PCI_D0);
-        err = pci_enable_device(pdev);
-        pci_restore_state(pdev);
 
-        /*
-         * Suspend/Resume resets the PCI configuration space, so we have to
-         * re-disable the RETRY_TIMEOUT register (0x41) to keep PCI Tx retries
-         * from interfering with C3 CPU state. pci_restore_state won't help
-         * here since it only restores the first 64 bytes pci config header.
-         */
-        pci_write_config_byte(pdev, 0x41, 0x00);
-
-        iwl4965_resume(priv);
+        if (priv->is_open)
+                iwl4965_mac_start(priv->hw);
 
+        clear_bit(STATUS_IN_SUSPEND, &priv->status);
         return 0;
 }