v4.19.13 snapshot.
diff --git a/drivers/pnp/isapnp/compat.c b/drivers/pnp/isapnp/compat.c
new file mode 100644
index 0000000..6c845b6
--- /dev/null
+++ b/drivers/pnp/isapnp/compat.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * compat.c - A series of functions to make it easier to convert drivers that use
+ * the old isapnp APIs. If possible use the new APIs instead.
+ *
+ * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
+ */
+
+#include <linux/module.h>
+#include <linux/isapnp.h>
+#include <linux/string.h>
+
+static void pnp_convert_id(char *buf, unsigned short vendor,
+ unsigned short device)
+{
+ sprintf(buf, "%c%c%c%x%x%x%x",
+ 'A' + ((vendor >> 2) & 0x3f) - 1,
+ 'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
+ 'A' + ((vendor >> 8) & 0x1f) - 1,
+ (device >> 4) & 0x0f, device & 0x0f,
+ (device >> 12) & 0x0f, (device >> 8) & 0x0f);
+}
+
+struct pnp_card *pnp_find_card(unsigned short vendor, unsigned short device,
+ struct pnp_card *from)
+{
+ char id[8];
+ char any[8];
+ struct list_head *list;
+
+ pnp_convert_id(id, vendor, device);
+ pnp_convert_id(any, ISAPNP_ANY_ID, ISAPNP_ANY_ID);
+
+ list = from ? from->global_list.next : pnp_cards.next;
+
+ while (list != &pnp_cards) {
+ struct pnp_card *card = global_to_pnp_card(list);
+
+ if (compare_pnp_id(card->id, id) || (memcmp(id, any, 7) == 0))
+ return card;
+ list = list->next;
+ }
+ return NULL;
+}
+
+struct pnp_dev *pnp_find_dev(struct pnp_card *card, unsigned short vendor,
+ unsigned short function, struct pnp_dev *from)
+{
+ char id[8];
+ char any[8];
+
+ pnp_convert_id(id, vendor, function);
+ pnp_convert_id(any, ISAPNP_ANY_ID, ISAPNP_ANY_ID);
+ if (card == NULL) { /* look for a logical device from all cards */
+ struct list_head *list;
+
+ list = pnp_global.next;
+ if (from)
+ list = from->global_list.next;
+
+ while (list != &pnp_global) {
+ struct pnp_dev *dev = global_to_pnp_dev(list);
+
+ if (compare_pnp_id(dev->id, id) ||
+ (memcmp(id, any, 7) == 0))
+ return dev;
+ list = list->next;
+ }
+ } else {
+ struct list_head *list;
+
+ list = card->devices.next;
+ if (from) {
+ list = from->card_list.next;
+ if (from->card != card) /* something is wrong */
+ return NULL;
+ }
+ while (list != &card->devices) {
+ struct pnp_dev *dev = card_to_pnp_dev(list);
+
+ if (compare_pnp_id(dev->id, id))
+ return dev;
+ list = list->next;
+ }
+ }
+ return NULL;
+}
+
+EXPORT_SYMBOL(pnp_find_card);
+EXPORT_SYMBOL(pnp_find_dev);