Got Permission denied error message when issuing flash_eraseall on mtd1 partition

[Ian Phan]

Hello,
 
I am new to Linux development and I try to get JFFS2 mounted on the 5 MB (mtd1) partition of the on-board 8 MB NOR flash on the Freescale MPC8349EMDS. When the linux kernel (2.6.14.7-selinux1-WR1.4aq_cgl) comes up, I can see the 4 mtd partitions.  I can see these partitions using cat /proc/mtd and ls /dev/mtd*.  I even able to issue flash_info /dev/mtd1 command.  However, when I issue flash_eraseall /dev/mtd1, I got the following error: "flash_erase: /dev/mtd1: Permission denied" as shown below.
 
Can anyone tell me why I am getting this error?
 
Thanks, 
Ian

======================================================================
 
# cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00020000 00020000 "HRCW"
mtd1: 00500000 00020000 "JFFS2"
mtd2: 00100000 00020000 "Kernel"
mtd3: 00100000 00020000 "U-Boot"
#
 
# ls -lLat /dev/mtd*
brw-rw-r--    1 root     root      31,   3 Apr 18  2007 /dev/mtdblock3
brw-rw-r--    1 root     root      31,   2 Apr 18  2007 /dev/mtdblock2
brw-rw-r--    1 root     root      31,   1 Apr 18  2007 /dev/mtdblock1
brw-rw-r--    1 root     root      31,   0 Apr 18  2007 /dev/mtdblock0
crw-rw-r--    1 root     root      90,   3 Apr 18  2007 /dev/mtd3
crw-rw-r--    1 root     root      90,   2 Apr 18  2007 /dev/mtd2
crw-rw-r--    1 root     root      90,   1 Apr 18  2007 /dev/mtd1
crw-rw-r--    1 root     root      90,   0 Apr 18  2007 /dev/mtd0 #
 
# flash_info /dev/mtd1
MTD_open
MTD_ioctl
Device /dev/mtd1MTD_close
 has 0 erase regions
#
 
# flash_eraseall /dev/mtd1
MTD_open
flash_eraseall: /dev/mtd1: Permission denied
#
 
# whoami
root
#
 
# uname -r
2.6.14.7-selinux1-WR1.4aq_cgl