rapdio/tsi721: Use PCI Express Capability accessors

Use PCI Express Capability access functions to simplify tsi721 driver.

[bhelgaas: use word (16-bit) accesses for PCI_EXP_DEVCTL, PCI_EXP_DEVCTL2]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alexandre Bounine <alexandre.bounine@idt.com>

drivers/rapidio/devices/tsi721.c

@@ -2212,9 +2212,8 @@ static int __devinit tsi721_probe(struct pci_dev *pdev,
 				  const struct pci_device_id *id)
 {
 	struct tsi721_device *priv;
-	int i, cap;
+	int i;
 	int err;
-	u32 regval;
 
 	priv = kzalloc(sizeof(struct tsi721_device), GFP_KERNEL);
 	if (priv == NULL) {
@@ -2320,20 +2319,16 @@ static int __devinit tsi721_probe(struct pci_dev *pdev,
 			dev_info(&pdev->dev, "Unable to set consistent DMA mask\n");
 	}
 
-	cap = pci_pcie_cap(pdev);
-	BUG_ON(cap == 0);
+	BUG_ON(!pci_is_pcie(pdev));
 
 	/* Clear "no snoop" and "relaxed ordering" bits, use default MRRS. */
-	pci_read_config_dword(pdev, cap + PCI_EXP_DEVCTL, &regval);
-	regval &= ~(PCI_EXP_DEVCTL_READRQ | PCI_EXP_DEVCTL_RELAX_EN |
-		    PCI_EXP_DEVCTL_NOSNOOP_EN);
-	regval |= 0x2 << MAX_READ_REQUEST_SZ_SHIFT;
-	pci_write_config_dword(pdev, cap + PCI_EXP_DEVCTL, regval);
+	pcie_capability_clear_and_set_word(pdev, PCI_EXP_DEVCTL,
+		PCI_EXP_DEVCTL_READRQ | PCI_EXP_DEVCTL_RELAX_EN |
+		PCI_EXP_DEVCTL_NOSNOOP_EN,
+		0x2 << MAX_READ_REQUEST_SZ_SHIFT);
 
 	/* Adjust PCIe completion timeout. */
-	pci_read_config_dword(pdev, cap + PCI_EXP_DEVCTL2, &regval);
-	regval &= ~(0x0f);
-	pci_write_config_dword(pdev, cap + PCI_EXP_DEVCTL2, regval | 0x2);
+	pcie_capability_clear_and_set_word(pdev, PCI_EXP_DEVCTL2, 0xf, 0x2);
 
 	/*
 	 * FIXUP: correct offsets of MSI-X tables in the MSI-X Capability Block