libata: clean up SFF init mess

The intention of using port_mask in SFF init helpers was to eventually
support exoctic configurations such as combination of legacy and
native port on the same controller.  This never became actually
necessary and the related code always has been subtly broken one way
or the other.  Now that new init model is in place, there is no reason
to make common helpers capable of handling all corner cases.  Exotic
cases can simply dealt within LLDs as necessary.

This patch removes port_mask handling in SFF init helpers.  SFF init
helpers don't take n_ports argument and interpret it into port_mask
anymore.  All information is carried via port_info.  n_ports argument
is dropped and always two ports are allocated.  LLD can tell SFF to
skip certain port by marking it dummy.  Note that SFF code has been
treating unuvailable ports this way for a long time until recent
breakage fix from Linus and is consistent with how other drivers
handle with unavailable ports.

This fixes 1-port legacy host handling still broken after the recent
native mode fix and simplifies SFF init logic.  The following changes
are made...

* ata_pci_init_native_host() and ata_init_legacy_host() both now try
  to initialized whatever they can and mark failed ports dummy.  They
  return 0 if any port is successfully initialized.

* ata_pci_prepare_native_host() and ata_pci_init_one() now doesn't
  take n_ports argument.  All info should be specified via port_info
  array.  Always two ports are allocated.

* ata_pci_init_bmdma() exported to be used by LLDs in exotic cases.

* port_info handling in all LLDs are standardized - all port_info
  arrays are const stack variable named ppi.  Unless the second port
  is different from the first, its port_info is specified as NULL
  (tells libata that it's identical to the last non-NULL port_info).

* pata_hpt37x/hpt3x2n: don't modify static variable directly.  Make an
  on-stack copy instead as ata_piix does.

* pata_uli: It has 4 ports instead of 2.  Don't use
  ata_pci_prepare_native_host().  Allocate the host explicitly and use
  init helpers.  It's simple enough.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 6 insertions, 7 deletions

diff --git a/drivers/ata/pata_hpt3x2n.c b/drivers/ata/pata_hpt3x2n.c
index ea1037d..f25154a 100644
--- a/drivers/ata/pata_hpt3x2n.c
+++ b/drivers/ata/pata_hpt3x2n.c
@@ -488,7 +488,7 @@ static int hpt3x2n_pci_clock(struct pci_dev *pdev)
 static int hpt3x2n_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	/* HPT372N and friends - UDMA133 */
-	static struct ata_port_info info = {
+	static const struct ata_port_info info = {
 		.sht = &hpt3x2n_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
 		.pio_mask = 0x1f,
@@ -496,8 +496,8 @@ static int hpt3x2n_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 		.udma_mask = 0x7f,
 		.port_ops = &hpt3x2n_port_ops
 	};
-	struct ata_port_info *port_info[2];
-	struct ata_port_info *port = &info;
+	struct ata_port_info port = info;
+	const struct ata_port_info *ppi[] = { &port, NULL };
 
 	u8 irqmask;
 	u32 class_rev;
@@ -585,9 +585,9 @@ static int hpt3x2n_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 
 	/* Set our private data up. We only need a few flags so we use
 	   it directly */
-	port->private_data = NULL;
+	port.private_data = NULL;
 	if (pci_mhz > 60) {
-		port->private_data = (void *)PCI66;
+		port.private_data = (void *)PCI66;
 		/*
 		 * On  HPT371N, if ATA clock is 66 MHz we must set bit 2 in
 		 * the MISC. register to stretch the UltraDMA Tss timing.
@@ -598,8 +598,7 @@ static int hpt3x2n_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 	}
 
 	/* Now kick off ATA set up */
-	port_info[0] = port_info[1] = port;
-	return ata_pci_init_one(dev, port_info, 2);
+	return ata_pci_init_one(dev, ppi);
 }
 
 static const struct pci_device_id hpt3x2n[] = {