ide: add struct ide_host (take 3)

* Add struct ide_host which keeps pointers to host's ports.

* Add ide_host_alloc[_all]() and ide_host_remove() helpers.

* Pass 'struct ide_host *host' instead of 'u8 *idx' to
  ide_device_add[_all]() and rename it to ide_host_register[_all]().

* Convert host drivers and core code to use struct ide_host.

* Remove no longer needed ide_find_port().

* Make ide_find_port_slot() static.

* Unexport ide_unregister().

v2:
* Add missing 'struct ide_host *host' to macide.c.

v3:
* Fix build problem in pmac.c (s/ide_alloc_host/ide_host_alloc/)
  (Noticed by Stephen Rothwell).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-pnp.c b/drivers/ide/ide-pnp.c
index 89cd5cb..4458ca6 100644
--- a/drivers/ide/ide-pnp.c
+++ b/drivers/ide/ide-pnp.c
@@ -29,7 +29,7 @@
 
 static int idepnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
 {
-	ide_hwif_t *hwif;
+	struct ide_host *host;
 	unsigned long base, ctl;
 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
 
@@ -59,14 +59,11 @@
 	hw.irq = pnp_irq(dev, 0);
 	hw.chipset = ide_generic;
 
-	hwif = ide_find_port();
-	if (hwif) {
-		u8 index = hwif->index;
-		u8 idx[4] = { index, 0xff, 0xff, 0xff };
+	host = ide_host_alloc(NULL, hws);
+	if (host) {
+		pnp_set_drvdata(dev, host);
 
-		pnp_set_drvdata(dev, hwif);
-
-		ide_device_add(idx, NULL, hws);
+		ide_host_register(host, NULL, hws);
 
 		return 0;
 	}
@@ -79,9 +76,9 @@
 
 static void idepnp_remove(struct pnp_dev *dev)
 {
-	ide_hwif_t *hwif = pnp_get_drvdata(dev);
+	struct ide_host *host = pnp_get_drvdata(dev);
 
-	ide_unregister(hwif);
+	ide_host_remove(host);
 
 	release_region(pnp_port_start(dev, 1), 1);
 	release_region(pnp_port_start(dev, 0), 8);