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>
diff --git a/drivers/ata/pata_via.c b/drivers/ata/pata_via.c
index 3740644..e4c71f7 100644
--- a/drivers/ata/pata_via.c
+++ b/drivers/ata/pata_via.c
@@ -421,7 +421,7 @@
 static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	/* Early VIA without UDMA support */
-	static struct ata_port_info via_mwdma_info = {
+	static const struct ata_port_info via_mwdma_info = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -429,7 +429,7 @@
 		.port_ops = &via_port_ops
 	};
 	/* Ditto with IRQ masking required */
-	static struct ata_port_info via_mwdma_info_borked = {
+	static const struct ata_port_info via_mwdma_info_borked = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -437,7 +437,7 @@
 		.port_ops = &via_port_ops_noirq,
 	};
 	/* VIA UDMA 33 devices (and borked 66) */
-	static struct ata_port_info via_udma33_info = {
+	static const struct ata_port_info via_udma33_info = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -446,7 +446,7 @@
 		.port_ops = &via_port_ops
 	};
 	/* VIA UDMA 66 devices */
-	static struct ata_port_info via_udma66_info = {
+	static const struct ata_port_info via_udma66_info = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -455,7 +455,7 @@
 		.port_ops = &via_port_ops
 	};
 	/* VIA UDMA 100 devices */
-	static struct ata_port_info via_udma100_info = {
+	static const struct ata_port_info via_udma100_info = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -464,7 +464,7 @@
 		.port_ops = &via_port_ops
 	};
 	/* UDMA133 with bad AST (All current 133) */
-	static struct ata_port_info via_udma133_info = {
+	static const struct ata_port_info via_udma133_info = {
 		.sht = &via_sht,
 		.flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
 		.pio_mask = 0x1f,
@@ -472,7 +472,8 @@
 		.udma_mask = 0x7f,	/* FIXME: should check north bridge */
 		.port_ops = &via_port_ops
 	};
-	struct ata_port_info *port_info[2], *type;
+	struct ata_port_info type;
+	const struct ata_port_info *ppi[] = { &type, NULL };
 	struct pci_dev *isa = NULL;
 	const struct via_isa_bridge *config;
 	static int printed_version;
@@ -517,25 +518,25 @@
 	switch(config->flags & VIA_UDMA) {
 		case VIA_UDMA_NONE:
 			if (config->flags & VIA_NO_UNMASK)
-				type = &via_mwdma_info_borked;
+				type = via_mwdma_info_borked;
 			else
-				type = &via_mwdma_info;
+				type = via_mwdma_info;
 			break;
 		case VIA_UDMA_33:
-			type = &via_udma33_info;
+			type = via_udma33_info;
 			break;
 		case VIA_UDMA_66:
-			type = &via_udma66_info;
+			type = via_udma66_info;
 			/* The 66 MHz devices require we enable the clock */
 			pci_read_config_dword(pdev, 0x50, &timing);
 			timing |= 0x80008;
 			pci_write_config_dword(pdev, 0x50, timing);
 			break;
 		case VIA_UDMA_100:
-			type = &via_udma100_info;
+			type = via_udma100_info;
 			break;
 		case VIA_UDMA_133:
-			type = &via_udma133_info;
+			type = via_udma133_info;
 			break;
 		default:
 			WARN_ON(1);
@@ -550,10 +551,9 @@
 	}
 
 	/* We have established the device type, now fire it up */
-	type->private_data = (void *)config;
+	type.private_data = (void *)config;
 
-	port_info[0] = port_info[1] = type;
-	return ata_pci_init_one(pdev, port_info, 2);
+	return ata_pci_init_one(pdev, ppi);
 }
 
 #ifdef CONFIG_PM