mwifiex: enable MSI interrupt support in pcie

Newer pcie devices (8897 onwards) support MSI. This
patch enables it.

Signed-off-by: Avinash Patil <[e-mail]>
Signed-off-by: Amitkumar Karwar <[e-mail]>
Signed-off-by: Kalle Valo <[e-mail]>

drivers/net/wireless/marvell/mwifiex/pcie.c

···
 	kfree(card);
 }
 
+static int mwifiex_pcie_request_irq(struct mwifiex_adapter *adapter)
+{
+	int ret;
+	struct pcie_service_card *card = adapter->card;
+	struct pci_dev *pdev = card->dev;
+
+	if (pci_enable_msi(pdev) != 0)
+		pci_disable_msi(pdev);
+	else
+		card->msi_enable = 1;
+
+	mwifiex_dbg(adapter, INFO, "msi_enable = %d\n", card->msi_enable);
+
+	ret = request_irq(pdev->irq, mwifiex_pcie_interrupt, IRQF_SHARED,
+			  "MRVL_PCIE", pdev);
+	if (ret) {
+		pr_err("request_irq failed: ret=%d\n", ret);
+		adapter->card = NULL;
+		return -1;
+	}
+
+	return 0;
+}
+
 /*
  * This function registers the PCIE device.
  *
···
  */
 static int mwifiex_register_dev(struct mwifiex_adapter *adapter)
 {
-	int ret;
 	struct pcie_service_card *card = adapter->card;
 	struct pci_dev *pdev = card->dev;
 
 	/* save adapter pointer in card */
 	card->adapter = adapter;
 
-	ret = request_irq(pdev->irq, mwifiex_pcie_interrupt, IRQF_SHARED,
-			  "MRVL_PCIE", pdev);
-	if (ret) {
-		mwifiex_dbg(adapter, ERROR,
-			    "request_irq failed: ret=%d\n", ret);
-		adapter->card = NULL;
+	if (mwifiex_pcie_request_irq(adapter))
 		return -1;
-	}
 
 	adapter->dev = &pdev->dev;
 	adapter->tx_buf_size = card->pcie.tx_buf_size;

drivers/net/wireless/marvell/mwifiex/pcie.h

···
 	dma_addr_t sleep_cookie_pbase;
 	void __iomem *pci_mmap;
 	void __iomem *pci_mmap1;
+	int msi_enable;
 };
 
 static inline int