1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
index 6a196c27b0aa..875429728021 100644
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -1444,6 +1444,54 @@ static int ide_sysfs_register_port(ide_hwif_t *hwif)
         return rc;
 }
 
+/**
+ *      ide_find_port_slot      -       find free ide_hwifs[] slot
+ *      @d: IDE port info
+ *
+ *      Return the new hwif.  If we are out of free slots return NULL.
+ */
+
+ide_hwif_t *ide_find_port_slot(const struct ide_port_info *d)
+{
+        ide_hwif_t *hwif;
+        int i;
+        u8 bootable = (d && (d->host_flags & IDE_HFLAG_NON_BOOTABLE)) ? 0 : 1;
+
+        /*
+         * Claim an unassigned slot.
+         *
+         * Give preference to claiming other slots before claiming ide0/ide1,
+         * just in case there's another interface yet-to-be-scanned
+         * which uses ports 0x1f0/0x170 (the ide0/ide1 defaults).
+         *
+         * Unless there is a bootable card that does not use the standard
+         * ports 0x1f0/0x170 (the ide0/ide1 defaults).
+         */
+        if (bootable) {
+                i = (d && (d->host_flags & IDE_HFLAG_QD_2ND_PORT)) ? 1 : 0;
+
+                for (; i < MAX_HWIFS; i++) {
+                        hwif = &ide_hwifs[i];
+                        if (hwif->chipset == ide_unknown)
+                                return hwif;
+                }
+        } else {
+                for (i = 2; i < MAX_HWIFS; i++) {
+                        hwif = &ide_hwifs[i];
+                        if (hwif->chipset == ide_unknown)
+                                return hwif;
+                }
+                for (i = 0; i < 2 && i < MAX_HWIFS; i++) {
+                        hwif = &ide_hwifs[i];
+                        if (hwif->chipset == ide_unknown)
+                                return hwif;
+                }
+        }
+
+        return NULL;
+}
+EXPORT_SYMBOL_GPL(ide_find_port_slot);
+
 int ide_device_add_all(u8 *idx, const struct ide_port_info *d)
 {
         ide_hwif_t *hwif, *mate = NULL;