iwlwifi: workaround interrupt handling no some platforms

This patch adds workaround for an interrupt related hardware bug on
some platforms.  (Apparently these platforms boot-up w/ INTX_DISABLED
set. -- JWL)

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 061ffba9c884c017c00970bc2a148fd3d6dc0602..c0b73c4d6f44d05c44adea2799e6152e5c099599 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -2602,6 +2602,7 @@ static int iwl4965_mac_start(struct ieee80211_hw *hw)
 {
        struct iwl_priv *priv = hw->priv;
        int ret;
+       u16 pci_cmd;
 
        IWL_DEBUG_MAC80211("enter\n");
 
@@ -2612,6 +2613,13 @@ static int iwl4965_mac_start(struct ieee80211_hw *hw)
        pci_restore_state(priv->pci_dev);
        pci_enable_msi(priv->pci_dev);
 
+       /* enable interrupts if needed: hw bug w/a */
+       pci_read_config_word(priv->pci_dev, PCI_COMMAND, &pci_cmd);
+       if (pci_cmd & PCI_COMMAND_INTX_DISABLE) {
+               pci_cmd &= ~PCI_COMMAND_INTX_DISABLE;
+               pci_write_config_word(priv->pci_dev, PCI_COMMAND, pci_cmd);
+       }
+
        ret = request_irq(priv->pci_dev->irq, iwl4965_isr, IRQF_SHARED,
                          DRV_NAME, priv);
        if (ret) {