[PATCH v4 13/14] ata: ahci: add FLUSH EXT and STANDBY IMMEDIATE support during shutdown

Some AHCI controllers require ATA FLUSH EXT and STANDBY IMMEDIATE to be
issued before poweroff to ensure data integrity and proper device
shutdown. This patch introduces ahci_port_shutdown(), which sends these
commands using ahci_ata_nodata().

Signed-off-by: Luca Lauro <[email protected]>
---
 drivers/ata/ahci.c | 46 +++++-----------------------------------------
 1 file changed, 5 insertions(+), 41 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index c78d1953e4..9ac34b15fe 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -49,6 +49,11 @@
 #define ahci_debug(ahci, fmt, arg...) \
 	dev_dbg(ahci->dev, fmt, ##arg)
 
+#define ATA_CMD_FLUSH_EXT 0xEA
+#define ATA_CMD_STANDBYNOW1 0xE0
+
+static LIST_HEAD(ahci_devices);
+
 static const struct pci_device_id ahci_pci_tbl[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_MARVELL_EXT, 0x9170) },
 	{ 0, }
@@ -691,47 +696,6 @@ static void ahci_port_shutdown(struct ahci_port *port)
 		ahci_port_info(port, "STANDBY IMMEDIATE failed\n");
 }
 
-/* Full poweroff sequence */
-static void ahci_poweroff(struct poweroff_handler *handler, unsigned long flags)
-{
-	struct ahci_device *ahci;
-	int i, n_ports;
-
-	list_for_each_entry(ahci, &ahci_devices, list) {
-
-		if (!ahci->mmio_base)
-			continue;
-
-		/* FLUSH + STANDBY on all active ports */
-		n_ports = max_t(int, ahci->n_ports, fls(ahci->port_map));
-
-		for (i = 0; i < n_ports; i++) {
-			struct ahci_port *port = &ahci->ports[i];
-
-			if (!(ahci->port_map & (1 << i)))
-				continue;
-
-			ahci_port_shutdown(port);
-		}
-
-		/* (optional) shutsown controller after commands
-		* ahci_shutdown_host(ahci);
-		*/
-	}
-}
-
-static struct poweroff_handler ahci_po_handler = {
-	.poweroff = ahci_poweroff,
-	.priority = 200,   /* higher than gpio-poweroff */
-};
-
-static int ahci_register_poweroff(void)
-{
-	poweroff_handler_register(&ahci_po_handler);
-	return 0;
-}
-postcore_initcall(ahci_register_poweroff);
-
 static __maybe_unused struct of_device_id ahci_dt_ids[] = {
 	{
 		.compatible = "calxeda,hb-ahci",

-- 
2.47.3