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/legacy/buddha.c b/drivers/ide/legacy/buddha.c
index c61bc6a..2625667 100644
--- a/drivers/ide/legacy/buddha.c
+++ b/drivers/ide/legacy/buddha.c
@@ -150,18 +150,15 @@
 
 static int __init buddha_init(void)
 {
-	ide_hwif_t *hwif;
-	int i;
-
 	struct zorro_dev *z = NULL;
+	struct ide_host *host;
 	u_long buddha_board = 0;
 	BuddhaType type;
-	int buddha_num_hwifs;
+	int buddha_num_hwifs, i;
 
 	while ((z = zorro_find_device(ZORRO_WILDCARD, z))) {
 		unsigned long board;
 		hw_regs_t hw[MAX_NUM_HWIFS], *hws[] = { NULL, NULL, NULL, NULL };
-		u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
 
 		if (z->id == ZORRO_PROD_INDIVIDUAL_COMPUTERS_BUDDHA) {
 			buddha_num_hwifs = BUDDHA_NUM_HWIFS;
@@ -226,16 +223,12 @@
 			buddha_setup_ports(&hw[i], base, ctl, irq_port,
 					   ack_intr);
 
-			hwif = ide_find_port();
-			if (hwif) {
-				hwif->chipset = ide_generic;
-
-				hws[i] = &hw[i];
-				idx[i] = hwif->index;
-			}
+			hws[i] = &hw[i];
 		}
 
-		ide_device_add(idx, NULL, hws);
+		host = ide_host_alloc(NULL, hws);
+		if (host)
+			ide_host_register(host, NULL, hws);
 	}
 
 	return 0;