DCAN on beaglebone

Hi Dal,

Happy New Year.

I have the same problem with DCAN so I'm curious if you have found a solution.

Did you try to build DCAN as a module and with verbose debug enabled?

Did dmesg tell something? I just get this:

[    0.938135] CAN device driver interface
[    0.942129] CAN bus driver for Bosch D_CAN controller 1.0

.

.

[    1.179602] can: raw protocol (rev 20090105)
[    1.184062] can: broadcast manager protocol (rev 20090105 t)

According to http://processors.wiki.ti.com/index.php/AM335x-PSP_04.06.00.03_Release_Notes DCAN should be supported.

Thanks

/Benny

Hi Dal/Benny,

DCAN was tested on AM335X EVM but not on BeagleBone.

Basic pointers:-

1. Check the pin_mux settings are proper

2. Check the driver configuration is proper

http://processors.wiki.ti.com/index.php/Sitara_DCAN_Driver_Guide#Linux_Driver_Configuration

3. Follow user guide for basic usage

http://processors.wiki.ti.com/index.php/Sitara_DCAN_Driver_Guide#Driver_Usage

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi,

Got it working now with the following changes to the kernel source in LINUXEZSDK-AM335X 05.03.02.00 http://www.ti.com/tool/linuxezsdk-sitara

--- mux33xx.c.org       2011-12-01 22:57:39.000000000 +0100
+++ mux33xx.c   2012-01-08 22:30:35.352610949 +0100
@@ -315,10 +315,10 @@
                "uart0_txd", "spi1_cs1", "d_can0_rx", NULL,
                NULL, NULL, NULL, NULL),
        _AM33XX_MUXENTRY(UART1_CTSN, 0,
-               "uart1_ctsn", NULL, NULL, NULL,
+               "uart1_ctsn", NULL, "d_can0_tx", NULL,
                "spi1_cs0", NULL, NULL, NULL),
        _AM33XX_MUXENTRY(UART1_RTSN, 0,
-               "uart1_rtsn", NULL, NULL, NULL,
+               "uart1_rtsn", NULL, "d_can0_rx", NULL,
                "spi1_cs1", NULL, NULL, NULL),
        _AM33XX_MUXENTRY(UART1_RXD, 0,
                "uart1_rxd", "mmc1_sdwp", NULL, NULL,

--- board-am335xevm.c.org       2011-12-01 22:57:39.000000000 +0100
+++ board-am335xevm.c   2012-01-08 22:05:21.696664621 +0100
@@ -586,6 +586,12 @@
        {NULL, 0},
 };

+static struct pinmux_config d_can_bbs_pin_mux[] = {
+       {"uart1_ctsn.d_can0_tx", OMAP_MUX_MODE2 | AM33XX_PULL_ENBL},
+       {"uart1_rtsn.d_can0_rx", OMAP_MUX_MODE2 | AM33XX_PIN_INPUT_PULLUP},
+       {NULL, 0},
+};
+
 /*
 * @pin_mux - single module pin-mux structure which defines pin-mux
 *                      details for all its pins.
@@ -1239,6 +1245,11 @@
                        am33xx_d_can_init(1);
                }
                break;
+       case LOW_COST_EVM:
+               setup_pin_mux(d_can_bbs_pin_mux);
+               /* Instance Zero */
+               am33xx_d_can_init(0);
+               break;
        default:
                break;
        }
@@ -1438,6 +1449,7 @@
        {usb0_init,     DEV_ON_BASEBOARD, PROFILE_NONE},
        {usb1_init,     DEV_ON_BASEBOARD, PROFILE_NONE},
        {mmc0_init,     DEV_ON_BASEBOARD, PROFILE_NONE},
+       {d_can_init,    DEV_ON_BASEBOARD, PROFILE_NONE},
        {NULL, 0, 0},
 };

CAN tranceiver is mounted on expansion header P9.19 and P9.20

To bring the CAN interface up read http://processors.wiki.ti.com/index.php/Sitara_DCAN_Driver_Guide#Quick_Steps

Thanks

Benny

Hi Anil,

Should it be possible to use DCAN0 and DCAN1 at the same time?

I can use them one at a time, but get this error if I try to use them simultaneous.

[    0.848393] ------------[ cut here ]------------
[    0.853276] WARNING: at fs/sysfs/dir.c:455 sysfs_add_one+0xa4/0xb4()
[    0.859895] sysfs: cannot create duplicate filename '/devices/platform/d_can'

--

--

Should the init be done in another way than this?

/* Instance Zero */

am33xx_d_can_init(0);
/* Instance One */
am33xx_d_can_init(1);

Thanks

Benny

Hi Benny,

I am not sure about BeagleBone but on AM335x EVM DCAN1 is supported.

Check the schematics for any interdependency.

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

I can use them one at a time so nothing wrong with using DCAN1seen from HW. The problem is that I can't call both 

am33xx_d_can_init(0);

am33xx_d_can_init(1);

the second time I make the am33xx_d_can_init I get the error you can see in my previous post.

BR

Benny

Hi Anil,

Thanks for the help. The change of id to 0 / 1 solved the problem.

Should I report the problem somewhere so the id will be changed or do you do that?

BR

Benny

Sorry, but I don't have any "Verify Answer" button anywhere.

BR

Benny

Hi Benny,

    I modify the software link you, but it's not working on my beaglebone,see my test log:

root@am335x-evm:~# canconfig can0 bitrate 100000 ctrlmode triple-sampling on loopback on
can0 bitrate: 100000, sample-point: 0.875
can0 ctrlmode: loopback[ON], listen-only[OFF], tripple-sampling[ON],one-shot[OFF], berr-reporting[OFF]
root@am335x-evm:~# canconfig can0 start
[   51.096203] d_can d_can: can0: setting CAN BT = 0x1c0e
can0 state: ERROR-ACTIVE
root@am335x-evm:~# cansequence can0
interface = can0, family = 29, type = 3, proto = 1
write: No buffer space available
root@am335x-evm:~# cat /proc/net/can/stats

       42 transmitted frames (TXF)
        3 received frames (RXF)
        0 matched frames (RXMF)

        0 % total match ratio (RXMR)
        0 frames/s total tx rate (TXR)
        0 frames/s total rx rate (RXR)

        0 % current match ratio (CRXMR)
        0 frames/s current tx rate (CTXR)
        0 frames/s current rx rate (CRXR)

        0 % max match ratio (MRXMR)
       42 frames/s max tx rate (MTXR)
        3 frames/s max rx rate (MRXR)

        0 current receive list entries (CRCV)
        0 maximum receive list entries (MRCV)

can you help me?

Hi Tony,

To bring can0 up I use:

ip link set can0 type can bitrate 250000 triple-sampling on

ip link set can0 up

To send (example):

cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 0x77 0x88

To receive (example):

candump can0

which will give me something like:

root@am335x-evm:~# candump
interface = can0, family = 29, type = 3, proto = 1
<0x010> [8] 11 22 33 44 55 66 77 88

Hope that helps

BR

Benny

Hi Benny,

    Thank for you help, I also try the way to test like you before, but i can't get any CAN signal but 3.3V all the time on DCAN0_TX(P9.20 on BeagleBone),log as below:

am335x-evm login: root
root@am335x-evm:~# ip link set can0 type can bitrate 250000 triple-sampling on
root@am335x-evm:~# ip link set can0 up
[   38.435476] d_can d_can: can0: setting CAN BT = 0x1c05
root@am335x-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 0x77 0x88
interface = can0, family = 29, type = 3, proto = 1

    Do i miss anything?

BR

Tony

Hi Benny,

    Thanks for you help, I also try the way to test like you, but i can't get any CAN signal but 3.3V all the time on DCAN0_TX(P9.20 on BeagleBone),log as below:

am335x-evm login: root
root@am335x-evm:~# ip link set can0 type can bitrate 250000 triple-sampling on
root@am335x-evm:~# ip link set can0 up
[   38.435476] d_can d_can: can0: setting CAN BT = 0x1c05
root@am335x-evm:~# cansend can0 -i 0x10 0x11 0x22 0x33 0x44 0x55 0x66 0x77 0x88
interface = can0, family = 29, type = 3, proto = 1

    Do i miss anything?

BR

Tony

Hi Tony,

I have one question here

root@am335x-evm:~# cansequence can0
interface = can0, family = 29, type = 3, proto = 1
write: No buffer space available

Are you seeing this issue after transferring some packets? Better use cansequence in polling mode so that you will not see this issue.

root@am335x-evm:~# cansequence can0 -p

Some pointers:-

1. We have to use two boards for using the DCAN driver.

2. First try with lower bitrates let's say 50000 (50KBPS)

3. Follow the DCAN user guide http://processors.wiki.ti.com/index.php/DCAN_Driver_Guide

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi Anil,

    I have solve the problem of DCAN, and i found two key point may be the bug of the DCAN control that causes the problem:

1、If i don't connect any transceiver hardware, the DCAN do not Automatic Retransmission the frame(that is why i didn't found signal on CAN0_TX)

2、when initialization, event though the IE0、IE1and EIE of DCAN CTL is Disabled, the  interrupt of DCAN can occur.

Hi,

Someone asked me about the changes that were required to make both DCAN0 and 1 available.

Below is a patch for SDK 05.03.03 (PSP 04.06.00.03)

/Benny

**********************************************************

Date: Sat, 24 Mar 2012 12:41:25 +0100
Subject: [PATCH] CAN0 (DCAN0_RX P9.19, DCAN0_TX P9.20) and CAN1 (DCAN1_RX
 P9.24, DCAN1_TX P9.26) is working

---
 arch/arm/mach-omap2/board-am335xevm.c |   21 +++++++++++++++++++++
 arch/arm/mach-omap2/devices.c         |    4 ++--
 arch/arm/mach-omap2/mux33xx.c         |    8 ++++----
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-omap2/board-am335xevm.c b/arch/arm/mach-omap2/board-am335xevm.c
index 4e4286a..923bf7d 100644
--- a/arch/arm/mach-omap2/board-am335xevm.c
+++ b/arch/arm/mach-omap2/board-am335xevm.c
@@ -586,6 +586,18 @@ static struct pinmux_config d_can_ia_pin_mux[] = {
 	{NULL, 0},
 };
 
+static struct pinmux_config d_can0_bbs_pin_mux[] = {
+       {"uart1_ctsn.d_can0_tx", OMAP_MUX_MODE2 | AM33XX_PULL_ENBL},
+       {"uart1_rtsn.d_can0_rx", OMAP_MUX_MODE2 | AM33XX_PIN_INPUT_PULLUP},
+       {NULL, 0},
+};
+
+static struct pinmux_config d_can1_bbs_pin_mux[] = {
+       {"uart1_rxd.d_can1_tx", OMAP_MUX_MODE2 | AM33XX_PULL_ENBL},
+       {"uart1_txd.d_can1_rx", OMAP_MUX_MODE2 | AM33XX_PIN_INPUT_PULLUP},
+       {NULL, 0},
+};
+
 /*
 * @pin_mux - single module pin-mux structure which defines pin-mux
 *			details for all its pins.
@@ -1239,6 +1251,14 @@ static void d_can_init(int evm_id, int profile)
 			am33xx_d_can_init(1);
 		}
 		break;
+	case LOW_COST_EVM:
+		/* Instance Zero */
+		setup_pin_mux(d_can0_bbs_pin_mux);
+		am33xx_d_can_init(0);
+		/* Instance One */
+		setup_pin_mux(d_can1_bbs_pin_mux);
+		am33xx_d_can_init(1);
+		break;
 	default:
 		break;
 	}
@@ -1438,6 +1458,7 @@ static struct evm_dev_cfg beaglebone_dev_cfg[] = {
 	{usb0_init,	DEV_ON_BASEBOARD, PROFILE_NONE},
 	{usb1_init,	DEV_ON_BASEBOARD, PROFILE_NONE},
 	{mmc0_init,	DEV_ON_BASEBOARD, PROFILE_NONE},
+	{d_can_init,	DEV_ON_BASEBOARD, PROFILE_NONE},
 	{NULL, 0, 0},
 };
 
diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c
index 6edc9b5..d03bc71 100644
--- a/arch/arm/mach-omap2/devices.c
+++ b/arch/arm/mach-omap2/devices.c
@@ -1379,7 +1379,7 @@ static struct platform_device am33xx_d_can0_device = {
 		.platform_data = &am33xx_evm_d_can0_pdata,
 	},
 	.name		= "d_can",
-	.id		= -1,
+	.id		= 0,
 	.num_resources	= ARRAY_SIZE(am33xx_d_can0_resources),
 	.resource	= am33xx_d_can0_resources,
 };
@@ -1421,7 +1421,7 @@ static struct platform_device am33xx_d_can1_device = {
 		.platform_data = &am33xx_evm_d_can1_pdata,
 	},
 	.name		= "d_can",
-	.id		= -1,
+	.id		= 1,
 	.num_resources	= ARRAY_SIZE(am33xx_d_can1_resources),
 	.resource	= am33xx_d_can1_resources,
 };
diff --git a/arch/arm/mach-omap2/mux33xx.c b/arch/arm/mach-omap2/mux33xx.c
index a7e120f..c6644f4 100644
--- a/arch/arm/mach-omap2/mux33xx.c
+++ b/arch/arm/mach-omap2/mux33xx.c
@@ -315,16 +315,16 @@ static struct omap_mux __initdata am33xx_muxmodes[] = {
 		"uart0_txd", "spi1_cs1", "d_can0_rx", NULL,
 		NULL, NULL, NULL, NULL),
 	_AM33XX_MUXENTRY(UART1_CTSN, 0,
-		"uart1_ctsn", NULL, NULL, NULL,
+		"uart1_ctsn", NULL, "d_can0_tx", NULL,
 		"spi1_cs0", NULL, NULL, NULL),
 	_AM33XX_MUXENTRY(UART1_RTSN, 0,
-		"uart1_rtsn", NULL, NULL, NULL,
+		"uart1_rtsn", NULL, "d_can0_rx", NULL,
 		"spi1_cs1", NULL, NULL, NULL),
 	_AM33XX_MUXENTRY(UART1_RXD, 0,
-		"uart1_rxd", "mmc1_sdwp", NULL, NULL,
+		"uart1_rxd", "mmc1_sdwp", "d_can1_tx", NULL,
 		NULL, "pr1_uart0_rxd_mux1", NULL, NULL),
 	_AM33XX_MUXENTRY(UART1_TXD, 0,
-		"uart1_txd", "mmc2_sdwp", NULL, NULL,
+		"uart1_txd", "mmc2_sdwp", "d_can1_rx", NULL,
 		NULL, "pr1_uart0_txd_mux1", NULL, NULL),
 	_AM33XX_MUXENTRY(I2C0_SDA, 0,
 		"i2c0_sda", NULL, NULL, NULL,
-- 
1.7.5.4

Hi AnilKumar,

Where set the mode register of   AM335X ?

I want to  make   DCAN1   work,  but  I  can't  find  conf_<module>_<pin> Register  in the kernel. I need to set  the pin of DCAN work in mode2.

How to set the work mode and where is the document?

I use linux-3.1.0-psp04.06.00.03.sdk ,the hardware is beaglebone!

Hi  Benny,

I am a new user of beaglebone ,I want  to develop DCAN of beaglebone ..I use" linux-3.1.0-psp04.06.00.03.sdk",

but how to set the register work in mode2,where is the register document?

Hi Zerong,

Apply above patch on top of PSP release and it will work.

Benny tried two DCAN instances and it was working.

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

H i Anil,

Thanks for your help ,my dcan is drove up . But I can't find  any "Verify Answer" button .

Now ,I have a nother trouble:

I short the rx and tx of can1.No external transceiver.

root@am335x-evm:~# canconfig can1 bitrate 100000 ctrlmode triple-sampling on loopback on
can1 bitrate: 100000, sample-point: 0.875
can1 ctrlmode: loopback[ON], listen-only[OFF], tripple-sampling[ON],one-shot[OFF], berr-reporting[OFF]
root@am335x-evm:~# canconfig can1 start
[ 2445.703423] d_can d_can.1: can1: setting CAN BT = 0x1c0e
can1 state: ERROR-ACTIVE
root@am335x-evm:~# cat /proc/net/can/stats

       44 transmitted frames (TXF)
        3 received frames (RXF)
        0 matched frames (RXMF)

        0 % total match ratio (RXMR)
        0 frames/s total tx rate (TXR)
        0 frames/s total rx rate (RXR)

        0 % current match ratio (CRXMR)
        0 frames/s current tx rate (CTXR)
        0 frames/s current rx rate (CRXR)

        0 % max match ratio (MRXMR)
       42 frames/s max tx rate (MTXR)
        3 frames/s max rx rate (MRXR)

        0 current receive list entries (CRCV)
        1 maximum receive list entries (MRCV)

Thanks!Looking forward to your help！

Hi Benny,

 How to connect the hardware when you test?

Do you use two boards, do you need  transceiver？

Are you execute cansend on one board  ,and  execute  candump on another  board  ?

Thanks!Looking forward to your help！

Hi Zerong,

If you are testing the loopback mode then you have to do both (candump and cansend) in the same console. Or you can do ssh and use both consoles for send & receive

$ candump can0 &

$ cansend can0 -i 9 0x1 0x2 0x3 0x4 0x5 0x6 0x7 0x8

Regards

AnilKumar

Hi Zerong,

The first test I did was with tranceivers on one board and then connect them. I used the setup as Anil explained using ssh to have two (or more) terminals to run candump and cansend.

BR

Benny

Hi Anil,

1、 When I am testing the loopback mode, I short the rx and tx of can1, no  transceiver. I do the both (candump and cansend) in the same console.

But  have below troubles:

root@am335x-evm:~# canconfig can1 bitrate 50000 ctrlmode triple-sampling on loop

back on

can1 bitrate: 50000, sample-point: 0.875

can1 ctrlmode: loopback[ON], listen-only[OFF], tripple-sampling[ON],one-shot[OFF], berr-reporting[OFF]

root@am335x-evm:~# canconfig can1 start

[ 1668.895032] d_can d_can.1: can1: setting CAN BT = 0x1c1d

can1 state: ERROR-ACTIVE   ( why ??)

root@am335x-evm:~# cansequence can1

interface = can1, family = 29, type = 3, proto = 1

write: No buffer space available

root@am335x-evm:~# cansequence can0 -p

interface = can0, family = 29, type = 3, proto = 1

……(have nothing)

root@am335x-evm:~# candump can1  (I can't receive anything  )

According  to AM335x TRM 23.3.1.3.2 Loopback Mode : we should set  bit LBack in the test register to one. How to set ,I don't know where is the register?  

Do we need to set register of DCAN when communicate, I can't  set anything .

Please help me ! Thank you !

Zerong,

ERROR-ACTIVE says that bus is in working mode. you can look at enum can_state in "include/linux/can/netlink.h" file to know more details of the ERROR states.

Are you porting two d_can instances at a time?

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi Anil,

Thanks for your help ,my dcan is working rightly.

Now I want to find the C source code of   test app (cansend 、 candump、cansequence ), but I can't find in the kernel package and rootfs package.

Do you have and provide to me ? or Where can  I get them ?

Thanks!Looking forward to your help！

Do you mean can-utils: http://gitorious.org/linux-can/can-utils

See this resource for further SocketCAN related info: https://plus.google.com/u/0/117660856159215855502

Yegor

Hi Zerong,

You can refer this section

http://processors.wiki.ti.com/index.php/AM335X_DCAN_Driver_Guide#CAN_Utilities

Regards

AnilKumar

Hi,

Can anyone help me , how to test the CAN controller in loop-back mode in Am335x. So that i can check whether my transmitted and received data ( through CAN interface vcan0 ) are same using candump. 

With Regards,

Priya.

Hi tony,

We are also facing the same problem as you said in previous post. We are also not getting CAN signal but 3.3V all the time DCAN0_TX(P9.20 on beaglebone) , but when we do software loopback using CAN utilities , it is able to transmit and receive data which is also confirmed in cat /proc/net/dev . so with this, we hope canutils are configured properly . Did you change any kernel source code other than from the below link : 

http://e2e.ti.com/support/dsp/sitara_arm174_microprocessors/f/791/t/154560.aspx?pi69795=2 

Hope you can help us !

Thanks ,

Dhiv.

Hi Tony

Can you please guide us on how your problem was solved?

We have the same issue of no transmission in CAN0_TX lines. We have connected CAN transceivers SN54HVD230 on CAN port.

Thanks and regards

Rajam

The issue was with the transceiver connection. Issue is resolved and able to communicate between CAN0 and CAN1 interfaces of the board. 

Thanks and regards

Rajam

Hi all

We want to share our experience on CAN interface bring up and testing in Linux using Beaglebone board with the forum.

Please find the PPT (d_can_on_Beaglebone.pptx) prepared by our team on this. 

Thanks and regards

Rajam

Hi Benny,

I am try to do it like you,add code, rebuild kernel, start the board, I can find can.0 in /sys/devices/platform/omap/ but can't find it in /dev/

Do I miss something?

Thanks.

Can you see can0 if you execute "ifconfig -a"?

After that you can activate it using iproute2 utility. See kernel's documentation Documentation/networking/can.txt and this script http://gitorious.org/linux-can/can-misc/blobs/master/etc/can_if for details.

SocketCAN wiki: http://elinux.org/CAN_Bus

Hi Z,

Yes as rfc2217 writes you have to bring the interfaces up.

It might help to read the powerpoint (d_can_on_Beaglebone.pptx)  from Rajam (posted just before your post). I have not checked it,but it seems to describe all the steps you have to do.

BR

Benny

Hi Benny,

Thanks for you reply, I am already fix it, there was something wrong with this function d_can_hw_raminit.

Regards.

When I bring board up, I need to mknod for can0:

mknod /dev/can0 c 91 0

After this command, it work:-)

Hi Tony,

Could you  please explain me  clearly. Even i am also not able to see signal provided muxing done properly when i tried for loop back in Test mode(When Sample point At Tx pin is enabled in Test Register).

Regards

Bhimesh.

Hi Rajam,

Could please explain me what was issue with trans receiver in board.

Regards,

Bhimesh.

Hi Bhimesh, 

I am answering based on referring to the records we have -- since it is quite sometime that we had done the testing. 

We had initially identified pin 1 wrongly in the transceiver IC and had done the connection. 

After identifying the correct pin 1 and reworking the connections correctly, we were able to see the activity in the Tx pin. 

Hope this helps, 

Thanks and regards

Rajam