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Date: Thu, 16 Sep 2004 11:49:09 +0100
From: David Vrabel <dvrabel@arcom.com>
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Subject: [patch] Only probe for device combinations that fit in map's
	bankwidth.
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Hi,

Recent MTD changed how chip probing is done and it now probes for chips 
of all bus widths.  On my board (IXP425 with 16-bit AMD AM29LV128 flash) 
probing for 8-bit wide devices cannot work because 8-bit writes/reads to 
16-bit devices aren't allowed (they cause data aborts). So...

Make genprobe_new_chip() only probe for combinations that fit in the 
map's bankwidth.

Index: linux-2.6-armbe/drivers/mtd/chips/gen_probe.c
===================================================================
--- linux-2.6-armbe.orig/drivers/mtd/chips/gen_probe.c	2004-09-15 
17:06:44.000000000 +0100
+++ linux-2.6-armbe/drivers/mtd/chips/gen_probe.c	2004-09-16 
11:37:15.000000000 +0100
@@ -172,8 +172,9 @@
  		for (type = 0; type < 3; type++) {
  			cfi->device_type = 1<<type;

-			if (cp->probe_chip(map, 0, NULL, cfi))
-				return 1;
+			if (cfi->device_type * cfi->interleave == map_bankwidth(map))
+				if (cp->probe_chip(map, 0, NULL, cfi))
+					return 1;
  		}
  	}
  	return 0;

David Vrabel
-- 
David Vrabel, Design Engineer

Arcom, Clifton Road           Tel: +44 (0)1223 411200 ext. 3233
Cambridge CB1 7EA, UK         Web: http://www.arcom.com/