ide: move legacy ISA/VLB ports handling to ide-legacy.c (v2)

* Move legacy ISA/VLB ports handling from ide-probe.c to ide-legacy.c.

* Add CONFIG_IDE_LEGACY config option to be selected by host drivers
  needing ide-legacy.c.

v2:
Fix CONFIG_IDE_LEGACY not being defined in Kconfig.
(from Takashi Iwai <tiwai@suse.de>)

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-legacy.c b/drivers/ide/ide-legacy.c
new file mode 100644
index 0000000..8c5dcbf
--- /dev/null
+++ b/drivers/ide/ide-legacy.c
@@ -0,0 +1,58 @@
+#include <linux/kernel.h>
+#include <linux/ide.h>
+
+static void ide_legacy_init_one(hw_regs_t **hws, hw_regs_t *hw,
+				u8 port_no, const struct ide_port_info *d,
+				unsigned long config)
+{
+	unsigned long base, ctl;
+	int irq;
+
+	if (port_no == 0) {
+		base = 0x1f0;
+		ctl  = 0x3f6;
+		irq  = 14;
+	} else {
+		base = 0x170;
+		ctl  = 0x376;
+		irq  = 15;
+	}
+
+	if (!request_region(base, 8, d->name)) {
+		printk(KERN_ERR "%s: I/O resource 0x%lX-0x%lX not free.\n",
+				d->name, base, base + 7);
+		return;
+	}
+
+	if (!request_region(ctl, 1, d->name)) {
+		printk(KERN_ERR "%s: I/O resource 0x%lX not free.\n",
+				d->name, ctl);
+		release_region(base, 8);
+		return;
+	}
+
+	ide_std_init_ports(hw, base, ctl);
+	hw->irq = irq;
+	hw->chipset = d->chipset;
+	hw->config = config;
+
+	hws[port_no] = hw;
+}
+
+int ide_legacy_device_add(const struct ide_port_info *d, unsigned long config)
+{
+	hw_regs_t hw[2], *hws[] = { NULL, NULL, NULL, NULL };
+
+	memset(&hw, 0, sizeof(hw));
+
+	if ((d->host_flags & IDE_HFLAG_QD_2ND_PORT) == 0)
+		ide_legacy_init_one(hws, &hw[0], 0, d, config);
+	ide_legacy_init_one(hws, &hw[1], 1, d, config);
+
+	if (hws[0] == NULL && hws[1] == NULL &&
+	    (d->host_flags & IDE_HFLAG_SINGLE))
+		return -ENOENT;
+
+	return ide_host_add(d, hws, NULL);
+}
+EXPORT_SYMBOL_GPL(ide_legacy_device_add);