ata: ahci_mvebu: add suspend/resume support

This commit adds suspend/resume support to the ahci_mvebu driver. The
suspend hook doesn't do anything special despite calling the generic
ahci_platform_suspend_host() function. However, the resume hook has to
restore the MBus windows configuration, as well as the regret option.

Tested on Marvell Armada 388 GP.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/ahci_mvebu.c

@@ -62,6 +62,26 @@ static void ahci_mvebu_regret_option(struct ahci_host_priv *hpriv)
 	writel(0x80, hpriv->mmio + AHCI_VENDOR_SPECIFIC_0_DATA);
 }
 
+static int ahci_mvebu_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	return ahci_platform_suspend_host(&pdev->dev);
+}
+
+static int ahci_mvebu_resume(struct platform_device *pdev)
+{
+	struct ata_host *host = platform_get_drvdata(pdev);
+	struct ahci_host_priv *hpriv = host->private_data;
+	const struct mbus_dram_target_info *dram;
+
+	dram = mv_mbus_dram_info();
+	if (dram)
+		ahci_mvebu_mbus_config(hpriv, dram);
+
+	ahci_mvebu_regret_option(hpriv);
+
+	return ahci_platform_resume_host(&pdev->dev);
+}
+
 static const struct ata_port_info ahci_mvebu_port_info = {
 	.flags	   = AHCI_FLAG_COMMON,
 	.pio_mask  = ATA_PIO4,
@@ -120,6 +140,8 @@ MODULE_DEVICE_TABLE(of, ahci_mvebu_of_match);
 static struct platform_driver ahci_mvebu_driver = {
 	.probe = ahci_mvebu_probe,
 	.remove = ata_platform_remove_one,
+	.suspend = ahci_mvebu_suspend,
+	.resume = ahci_mvebu_resume,
 	.driver = {
 		.name = DRV_NAME,
 		.of_match_table = ahci_mvebu_of_match,