OpenWrt Forum Archive

I using Kamikaze 8.09.1 on IXDPG425 board.

I compiled the package gpioctl_1.0-1_armeb.ipk and try to use it,
but actually NOT have /dev/gpio node created.
Why ?

root@OpenWrt:/# cat /proc/devices
Character devices:
1 mem
2 pty
3 ttyp
4 ttyS
5 /dev/tty
5 /dev/console
5 /dev/ptmx
10 misc
89 i2c
90 mtd
108 ppp
128 ptm
136 pts
254 rtc

Block devices:
259 blkext
31 mtdblock
root@OpenWrt:/#

Also, I try to use GPIO SYSFS interface:

root@OpenWrt:/# cd /sys/class/gpio/
root@OpenWrt:/sys/class/gpio# ls
export gpiochip0 unexport
root@OpenWrt:/sys/class/gpio# echo 12 > export
root@OpenWrt:/sys/class/gpio# ls
export gpio12 gpiochip0 unexport
root@OpenWrt:/sys/class/gpio# cd gpio12
root@OpenWrt:/sys/devices/virtual/gpio/gpio12# ls
direction subsystem uevent value
root@OpenWrt:/sys/devices/virtual/gpio/gpio12# echo out > direction
root@OpenWrt:/sys/devices/virtual/gpio/gpio12# cat direction
out

Any attempt to read/write value causes a kernel oops.

root@OpenWrt:/sys/devices/virtual/gpio/gpio12# echo 1 > value
Unable to handle kernel paging request at virtual address aaaaaad6
pgd = c787c000
[aaaaaad6] *pgd=00000000
Internal error: Oops: f3 [#1]
Modules linked in: nf_nat_tftp nf_conntrack_tftp nf_nat_irc nf_conntrack_irc nf_
nat_ftp nf_conntrack_ftp ipt_MASQUERADE iptable_nat nf_nat xt_NOTRACK iptable_ra
w xt_state nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack ipt_REJECT xt_TCPMSS ip
t_LOG xt_multiport xt_mac xt_limit iptable_mangle iptable_filter ip_tables xt_tc
pudp x_tables ppp_async ppp_generic slhc crc_ccitt
CPU: 0 Not tainted (2.6.28.10 #8)
pc : [<c0107fb0>] lr : [<c0028a04>] psr: a0000013
sp : c7a9deb0 ip : aaaaaaaa fp : c7a9dec4
r10: c7aec7f8 r9 : c7a9df78 r8 : c021e818
r7 : 00000002 r6 : 00000002 r5 : c7839000 r4 : c02181f4
r3 : c02347e0 r2 : 0000000c r1 : 0000000c r0 : 01921770
Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 000039ff Table: 0787c000 DAC: 00000015
Process ash (pid: 1258, stack limit = 0xc7a9c268)
Stack: (0xc7a9deb0 to 0xc7a9e000)
dea0: c7a9df14 0000000c c7a9ded4 c7a9dec8
dec0: c0028a04 c0107f94 c7a9deec c7a9ded8 c0106be0 c00289ac c40f0720 c0234870
dee0: c7a9df14 c7a9def0 c0107bec c0106bb0 4009f814 00000001 c7addd88 00000002
df00: c7aec7e0 c7adbc68 c7a9df24 c7a9df18 c01239cc c0107b60 c7a9df54 c7a9df28
df20: c00bbeb4 c01239b4 00000007 c7a99dc0 00000002 4009f814 c7a9df78 c001ff64
df40: c7a9c000 00000001 c7a9df74 c7a9df58 c007fbf8 c00bbd88 c7a99dc0 fffffff7
df60: 00000000 00000000 c7a9dfa4 c7a9df78 c008004c c007fb50 00000000 00000000
df80: c008b4a8 00000000 4009d320 00000002 00000002 00000004 00000000 c7a9dfa8
dfa0: c001fde0 c0080014 4009d320 00000002 00000001 4009f814 00000002 4006ac64
dfc0: 4009d320 00000002 00000002 00000004 00000002 00075284 00000001 00000000
dfe0: 000735ec beda4728 4006a328 40053f10 20000010 00000001 8a882aaa 0a90220a
Backtrace:
Function entered at [<c0107f88>] from [<c0028a04>]
r4:0000000c
Function entered at [<c00289a0>] from [<c0106be0>]
Function entered at [<c0106ba4>] from [<c0107bec>]
r4:c0234870
Function entered at [<c0107b54>] from [<c01239cc>]
r7:c7adbc68 r6:c7aec7e0 r5:00000002 r4:c7addd88
Function entered at [<c01239a8>] from [<c00bbeb4>]
Function entered at [<c00bbd7c>] from [<c007fbf8>]
Function entered at [<c007fb44>] from [<c008004c>]
r7:00000000 r6:00000000 r5:fffffff7 r4:c7a99dc0
Function entered at [<c0080008>] from [<c001fde0>]
r7:00000004 r6:00000002 r5:00000002 r4:4009d320
Code: e0000394 e59f301c e1a02001 e790c003 (e59c102c)
---[ end trace 45b95cc01572dcb7 ]---

Please press Enter to activate this console.

Any suggestion?

Solved!

I added the following change

Index: linux-2.6.28.10/arch/arm/mach-ixp4xx/coyote-setup.c
===================================================================
--- linux-2.6.28.10.orig/arch/arm/mach-ixp4xx/coyote-setup.c
+++ linux-2.6.28.10/arch/arm/mach-ixp4xx/coyote-setup.c
@@ -98,12 +98,29 @@ static struct platform_device ixdpg425_e
     }
 };
 
+static struct resource ixdpg425_gpio_resources[] = {
+    {
+        .name = "gpio",
+        .start  = IXDPG425_GPIO_MASK,
+        .end    = IXDPG425_GPIO_MASK,
+        .flags  = 0,
+    },
+};
+
+static struct platform_device ixdpg425_gpio = {
+    .name         = "GPIODEV",
+    .id         = -1,
+    .num_resources  = ARRAY_SIZE(ixdpg425_gpio_resources),
+    .resource       = ixdpg425_gpio_resources,
+};
+
 
 static struct platform_device *coyote_devices[] __initdata = {
     &coyote_flash,
     &coyote_uart,
     &ixdpg425_eth[0],
     &ixdpg425_eth[1],
+    &ixdpg425_gpio,
 };
 
 static void __init coyote_init(void)
Index: linux-2.6.28.10/arch/arm/mach-ixp4xx/include/mach/coyote.h
===================================================================
--- linux-2.6.28.10.orig/arch/arm/mach-ixp4xx/include/mach/coyote.h
+++ linux-2.6.28.10/arch/arm/mach-ixp4xx/include/mach/coyote.h
@@ -31,3 +31,16 @@
 #define    COYOTE_IDE_CTRL_PORT    0xFFFE10FC
 #define    COYOTE_IDE_ERROR_PORT    0xFFFE10E2
 
+/* gpio mask used by platform device */
+/* +---------------------------------------------------+
+ * | GPIO | Direction |            Function            |
+ * +------+-----------+--------------------------------+
+ * |   2  |    Out    |  SPI Clock                     |
+ * |   3  |    Out    |  SPI Data In (Data to Slic)    |
+ * |   4  |    In     |  SPI Data Out (Data from Slic) |
+ * |   5  |    Out    |  SPI Chip Select               |
+ * |  11  |    In     |  Slic Interrupt                |
+ * |  13  |    Out    |  Slic Reset                    |
+ * +---------------------------------------------------+
+ */
+#define IXDPG425_GPIO_MASK (1 << 2) | (1 << 3) | (1 << 4) | (1 << 5) | (1 << 11) | (1 << 13)

Access to the GPIOs has only purpose of slic debug.
Thanks to all