Patch(2.4.2): isapnp detect fix (wrong checksum)

Patch(2.4.2): isapnp detect fix (wrong checksum)

[Gunther Mayer]

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Hi,
this fix lets linux detect cards which don't
have a correct checksum.

These are probably common, it seems isapnptools _silently_
fixes this up !

Please apply if you like, comments welcome.

Regards, Gunther

--- linux/drivers/pnp/isapnp.c-2.4.2-orig       Fri Mar 16 09:08:47 2001
+++ linux/drivers/pnp/isapnp.c  Fri Mar 16 09:21:45 2001
@@ -993,10 +993,15 @@
                        header[4], header[5], header[6], header[7], header[8]);
                printk("checksum = 0x%x\n", checksum);
 #endif
-               if (checksum == 0x00 || checksum != header[8])  /* not valid CSN */
+               /* Don't be strict on the checksum, here !
+                   e.g. 'SCM SwapBox Plug and Play' has header[8]==0 (should be: b7)*/
+               if (header[8] == 0)
+                       ;
+               else if (checksum == 0x00 || checksum != header[8])     /* not valid CSN */
                        continue;
                if ((card = isapnp_alloc(sizeof(struct pci_bus))) == NULL)
                        continue;
+
                card->number = csn;
                card->vendor = (header[1] << 8) | header[0];
                card->device = (header[3] << 8) | header[2];

[-- Attachment #2: gmdiff-242-isapnp-checksum-swapbox --]
[-- Type: application/octet-stream, Size: 774 bytes --]

--- linux/drivers/pnp/isapnp.c-2.4.2-orig	Fri Mar 16 09:08:47 2001
+++ linux/drivers/pnp/isapnp.c	Fri Mar 16 09:21:45 2001
@@ -993,10 +993,15 @@
 			header[4], header[5], header[6], header[7], header[8]);
 		printk("checksum = 0x%x\n", checksum);
 #endif
-		if (checksum == 0x00 || checksum != header[8])	/* not valid CSN */
+		/* Don't be strict on the checksum, here !
+                   e.g. 'SCM SwapBox Plug and Play' has header[8]==0 (should be: b7)*/
+		if (header[8] == 0)
+			;
+		else if (checksum == 0x00 || checksum != header[8])	/* not valid CSN */
 			continue;
 		if ((card = isapnp_alloc(sizeof(struct pci_bus))) == NULL)
 			continue;
+
 		card->number = csn;
 		card->vendor = (header[1] << 8) | header[0];
 		card->device = (header[3] << 8) | header[2];