FAT32: fix support for superfloppy-format (PBR)

"Superfloppy" format (in U-Boot called PBR) did not work for FAT32 as
the file system type string is at a different location. Add support
for FAT32.

Signed-off-by: Wolfgang Denk <wd@denx.de>

disk/part_dos.c

@@ -77,8 +77,10 @@ static int test_block_type(unsigned char *buffer)
 	    (buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) {
 		return (-1);
 	} /* no DOS Signature at all */
-	if(strncmp((char *)&buffer[DOS_PBR_FSTYPE_OFFSET],"FAT",3)==0)
+	if (strncmp((char *)&buffer[DOS_PBR_FSTYPE_OFFSET],"FAT",3)==0 ||
+	    strncmp((char *)&buffer[DOS_PBR32_FSTYPE_OFFSET],"FAT32",5)==0) {
 		return DOS_PBR; /* is PBR */
+	}
 	return DOS_MBR;	    /* Is MBR */
 }
 

disk/part_dos.h

@@ -28,13 +28,14 @@
 #ifdef CONFIG_ISO_PARTITION
 /* Make the buffers bigger if ISO partition support is enabled -- CD-ROMS
    have 2048 byte blocks */
-#define DEFAULT_SECTOR_SIZE   2048
+#define DEFAULT_SECTOR_SIZE	2048
 #else
 #define DEFAULT_SECTOR_SIZE	512
 #endif
 #define DOS_PART_TBL_OFFSET	0x1be
 #define DOS_PART_MAGIC_OFFSET	0x1fe
 #define DOS_PBR_FSTYPE_OFFSET	0x36
+#define DOS_PBR32_FSTYPE_OFFSET	0x52
 #define DOS_PBR_MEDIA_TYPE_OFFSET	0x15
 #define DOS_MBR	0
 #define DOS_PBR	1

fs/fat/fat.c

@@ -50,6 +50,7 @@ static int cur_part = 1;
 #define DOS_PART_TBL_OFFSET	0x1be
 #define DOS_PART_MAGIC_OFFSET	0x1fe
 #define DOS_FS_TYPE_OFFSET	0x36
+#define DOS_FS32_TYPE_OFFSET	0x52
 
 int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
 {
@@ -94,7 +95,8 @@ fat_register_device(block_dev_desc_t *dev_desc, int part_no)
 	if (!get_partition_info (dev_desc, part_no, &info)) {
 		part_offset = info.start;
 		cur_part = part_no;
-	} else if (!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3)) {
+	} else if (strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3)==0 ||
+		   strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET],"FAT32",5)==0) {
 		/* ok, we assume we are on a PBR only */
 		cur_part = 1;
 		part_offset = 0;
@@ -105,7 +107,8 @@ fat_register_device(block_dev_desc_t *dev_desc, int part_no)
 	}
 
 #else
-	if (!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
+	if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
+	    (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 		/* ok, we assume we are on a PBR only */
 		cur_part = 1;
 		part_offset = 0;