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/arm/rapide.c b/drivers/ide/arm/rapide.c
index a45c2f6..11f3307 100644
--- a/drivers/ide/arm/rapide.c
+++ b/drivers/ide/arm/rapide.c
@@ -32,11 +32,10 @@
 static int __devinit
 rapide_probe(struct expansion_card *ec, const struct ecard_id *id)
 {
-	ide_hwif_t *hwif;
 	void __iomem *base;
+	struct ide_host *host;
 	int ret;
 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
-	u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
 
 	ret = ecard_request_resources(ec);
 	if (ret)
@@ -53,17 +52,15 @@
 	hw.chipset = ide_generic;
 	hw.dev = &ec->dev;
 
-	hwif = ide_find_port();
-	if (hwif == NULL) {
+	host = ide_host_alloc(&rapide_port_info, hws);
+	if (host == NULL) {
 		ret = -ENOENT;
 		goto release;
 	}
 
-	idx[0] = hwif->index;
+	ide_host_register(host, &rapide_port_info, hws);
 
-	ide_device_add(idx, &rapide_port_info, hws);
-
-	ecard_set_drvdata(ec, hwif);
+	ecard_set_drvdata(ec, host);
 	goto out;
 
  release:
@@ -74,11 +71,11 @@
 
 static void __devexit rapide_remove(struct expansion_card *ec)
 {
-	ide_hwif_t *hwif = ecard_get_drvdata(ec);
+	struct ide_host *host = ecard_get_drvdata(ec);
 
 	ecard_set_drvdata(ec, NULL);
 
-	ide_unregister(hwif);
+	ide_host_remove(host);
 
 	ecard_release_resources(ec);
 }