[libata] sata_vsc: support PCI MSI

Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/sata_vsc.c

@@ -94,8 +94,14 @@ enum {
 			      VSC_SATA_INT_ERROR_P    | VSC_SATA_INT_ERROR_R | \
 			      VSC_SATA_INT_ERROR_E    | VSC_SATA_INT_ERROR_M | \
 			      VSC_SATA_INT_PHY_CHANGE),
+
+	/* Host private flags (hp_flags) */
+	VSC_SATA_HP_FLAG_MSI    = (1 << 0),
 };
 
+struct vsc_sata_host_priv {
+	u32	hp_flags;
+};
 
 #define is_vsc_sata_int_err(port_idx, int_status) \
 	 (int_status & (VSC_SATA_INT_ERROR << (8 * port_idx)))
@@ -118,6 +124,20 @@ static void vsc_sata_scr_write (struct ata_port *ap, unsigned int sc_reg,
 }
 
 
+static void vsc_sata_host_stop(struct ata_host_set *host_set)
+{
+	struct vsc_sata_host_priv *hpriv = host_set->private_data;
+	struct pci_dev *pdev = to_pci_dev(host_set->dev);
+
+	if (hpriv->hp_flags & VSC_SATA_HP_FLAG_MSI)
+		pci_disable_msi(pdev);
+	else
+		pci_intx(pdev, 0);
+	kfree (hpriv);
+	ata_pci_host_stop(host_set);
+}
+
+
 static void vsc_intr_mask_update(struct ata_port *ap, u8 ctl)
 {
 	void __iomem *mask_addr;
@@ -312,7 +332,7 @@ static const struct ata_port_operations vsc_sata_ops = {
 	.scr_write		= vsc_sata_scr_write,
 	.port_start		= ata_port_start,
 	.port_stop		= ata_port_stop,
-	.host_stop		= ata_pci_host_stop,
+	.host_stop		= vsc_sata_host_stop,
 };
 
 static void __devinit vsc_sata_setup_port(struct ata_ioports *port, unsigned long base)
@@ -341,6 +361,7 @@ static int __devinit vsc_sata_init_one (struct pci_dev *pdev, const struct pci_d
 {
 	static int printed_version;
 	struct ata_probe_ent *probe_ent = NULL;
+	struct vsc_sata_host_priv *hpriv;
 	unsigned long base;
 	int pci_dev_busy = 0;
 	void __iomem *mmio_base;
@@ -382,6 +403,7 @@ static int __devinit vsc_sata_init_one (struct pci_dev *pdev, const struct pci_d
 		rc = -ENOMEM;
 		goto err_out_regions;
 	}
+
 	memset(probe_ent, 0, sizeof(*probe_ent));
 	probe_ent->dev = pci_dev_to_dev(pdev);
 	INIT_LIST_HEAD(&probe_ent->node);
@@ -393,19 +415,33 @@ static int __devinit vsc_sata_init_one (struct pci_dev *pdev, const struct pci_d
 	}
 	base = (unsigned long) mmio_base;
 
+	hpriv = kmalloc(sizeof(*hpriv), GFP_KERNEL);
+	if (!hpriv) {
+		rc = -ENOMEM;
+		goto err_out_iounmap;
+	}
+	memset(hpriv, 0, sizeof(*hpriv));
+
 	/*
 	 * Due to a bug in the chip, the default cache line size can't be used
 	 */
 	pci_write_config_byte(pdev, PCI_CACHE_LINE_SIZE, 0x80);
 
+	if (pci_enable_msi(pdev) == 0) {
+		hpriv->hp_flags |= VSC_SATA_HP_FLAG_MSI;
+		pci_intx(pdev, 0);
+	}
+	else
+		probe_ent->irq_flags = IRQF_SHARED;
+
 	probe_ent->sht = &vsc_sata_sht;
 	probe_ent->port_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
 				ATA_FLAG_MMIO;
 	probe_ent->port_ops = &vsc_sata_ops;
 	probe_ent->n_ports = 4;
 	probe_ent->irq = pdev->irq;
-	probe_ent->irq_flags = IRQF_SHARED;
 	probe_ent->mmio_base = mmio_base;
+	probe_ent->private_data = hpriv;
 
 	/* We don't care much about the PIO/UDMA masks, but the core won't like us
 	 * if we don't fill these
@@ -432,10 +468,12 @@ static int __devinit vsc_sata_init_one (struct pci_dev *pdev, const struct pci_d
 
 	/* FIXME: check ata_device_add return value */
 	ata_device_add(probe_ent);
-	kfree(probe_ent);
 
+	kfree(probe_ent);
 	return 0;
 
+err_out_iounmap:
+	pci_iounmap(pdev, mmio_base);
 err_out_free_ent:
 	kfree(probe_ent);
 err_out_regions: