ahci_platform: add suspend & resume support

index 45edba9..b8ffc02 100644
@@ -202,11 +202,63 @@ static int __devexit ahci_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int ahci_suspend(struct device *dev)
+{
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	void __iomem *mmio = hpriv->mmio;
+	u32 ctl;
+
+	/* AHCI spec rev1.1 section 8.3.3:
+	 * Software must disable interrupts prior to requesting a
+	 * transition of the HBA to D3 state.
+	 */
+	ctl = readl(mmio + HOST_CTL);
+	ctl &= ~HOST_IRQ_EN;
+	writel(ctl, mmio + HOST_CTL);
+	readl(mmio + HOST_CTL); /* flush */
+
+	return ata_host_suspend(host, PMSG_SUSPEND);
+}
+
+static int ahci_resume(struct device *dev)
+{
+	struct ahci_platform_data *pdata = dev_get_platdata(dev);
+	struct ata_host *host = dev_get_drvdata(dev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	int rc;
+
+	if (pdata && pdata->init) {
+		rc = pdata->init(dev, hpriv->mmio);
+		if (rc)
+			return rc;
+	}
+
+	rc = ahci_reset_controller(host);
+	if (rc)
+		return rc;
+
+	ahci_init_controller(host);
+	ata_host_resume(host);
+
+	return 0;
+}
+
+static const struct dev_pm_ops ahci_pm_ops = {
+	.suspend	= ahci_suspend,
+	.resume		= ahci_resume,
+};
+#endif
+
 static struct platform_driver ahci_driver = {
 	.remove = __devexit_p(ahci_remove),
 	.driver = {
 		.name = "ahci",
 		.owner = THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm	= &ahci_pm_ops,
+#endif
 	},
 	.id_table	= ahci_devtype,
 };