amd_flash: validate the bus address before we read/write it

git-svn-id: https://urjtag.svn.sourceforge.net/svnroot/urjtag/trunk@1860 b68d4a1b-bc3d-0410-92ed-d4ac073336b7

urjtag/ChangeLog

@@ -1,3 +1,8 @@
+2010-09-28  Mike Frysinger  <vapier@gentoo.org>
+
+  * src/flash/amd_flash.c (urj_flash_amd_detect): Move the bus address range
+    checks up to before we actually attempt to read/write the bus.
+
 2010-09-27  Mike Frysinger  <vapier@gentoo.org>
 
   * data/analog/bf533/bf533: Drop brackets from ADDR and DATA signals to match

urjtag/src/flash/amd_flash.c

@@ -101,6 +101,12 @@ urj_flash_amd_detect (urj_bus_t *bus, uint32_t adr,
         return URJ_STATUS_FAIL;
     }
 
+    (*cfi_array)->bus = bus;
+    (*cfi_array)->address = adr;
+    if (URJ_BUS_AREA (bus, adr, &area) != URJ_STATUS_OK)
+        // retain error state
+        return URJ_STATUS_FAIL;
+
     URJ_BUS_WRITE (bus, adr + 0x0, 0xf0);
     URJ_BUS_WRITE (bus, adr + 0x555, 0xaa);
     URJ_BUS_WRITE (bus, adr + 0x2AA, 0x55);
@@ -129,11 +135,6 @@ urj_flash_amd_detect (urj_bus_t *bus, uint32_t adr,
         break;
     }
 
-    (*cfi_array)->bus = bus;
-    (*cfi_array)->address = adr;
-    if (URJ_BUS_AREA (bus, adr, &area) != URJ_STATUS_OK)
-        // retain error status
-        return URJ_STATUS_FAIL;              /* bus width detection failed */
     unsigned int bw = area.width;
     int ba, i;
     if (bw != 8 && bw != 16 && bw != 32)