A20-CAN - Revision history

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

2021-06-10T08:04:39Z

‎Enabling A20-CAN in Olimage Linux

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

2021-06-10T08:01:19Z

‎Enabling A20-CAN in Olimage Linux

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

2021-06-10T07:56:49Z

‎Enabling A20-CAN in Olimage Linux

LubOlimex at 07:56, 10 June 2021

2021-06-10T07:56:10Z

LubOlimex at 11:52, 18 July 2018

2018-07-18T11:52:12Z

Olimex at 06:46, 24 May 2016

2016-05-24T06:46:35Z

Olimex: Created page with "File:A20-CAN.jpeg A20-CAN features: compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB connects to GPIO3 connector *allow CAN ne..."

2016-05-24T06:39:47Z

Created page with "File:A20-CAN.jpeg A20-CAN features: *compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB *connects to GPIO3 connector *allow CAN ne..."

New page

[[File:A20-CAN.jpeg]]

A20-CAN features:
*compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB
*connects to GPIO3 connector
*allow CAN networking of A20 boards running Linux
*Power LED
*PCB dimensions: 60x30mm

== Building Linux with CAN support ==
=== Get sources ===

Download kernel tree from:
git clone https://github.com/linux-sunxi/linux-sunxi.git

=== For Linux-Sunxi kernel (3.4) ===
The can driver is not in the kernel tree.
This is done with the following steps:

Download the can driver:
clone https://github.com/btolfa/sunxi-can-driver.git

Copy file to kernel tree:
cp -v sunxi-can-driver/sun7i_can.* linux-sunxi/drivers/net/can

Add Kconfig selection:
vi linux-sunxi/drivers/net/can/Kconfig

Add the following:
config CAN_SUN7I
tristate "Sun7i CAN bus controller"
default n
help
This is the Sun7i CAN BUS driver for android system by peter chen.

Modify Makefile:
vi linux-sunxi/drivers/net/can/Makefile

Add:
obj-$(CONFIG_CAN_SUN7I) += sun7i_can.o

'''NOTE:''' The example build is with default sun7i_defconfig. You can use your own.
Now you device tree is ready for build. However the new module is not selected.

Modify kernel:
cd linux-sunxi
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 sun7i_defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 menuconfig

Select from:
[*] Networking support --->
<*> CAN bus subsystem support --->
<*> CAN Device Drivers --->
[M] Sun7i CAN bus controller

Save current configuration and build:
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 uImage modules

Modify can section of script.bin file:
[can_para]
can_used = 1
can_tx = port:PH20<4><default><default><default>
can_rx = port:PH21<4><default><default><default>

Copy kernel and modules to SD-CARD and boot the system.

=== For Mainline kernel ===

In the mainline kernel there is support for CAN bus. However we need to
declare that it's gonna be used.

First of all checkout __sunxi_next__ branch:
cd linux-sunxi
git checkout -b sunxi-next origin/sunxi-next

Select __sunxi_defconfig__:
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 sunxi_defconfig

'''NOTE:''' By default can module is build as part of the kernel.
<br/>
'''NOTE:''' In the example we are gonna use A20-OLinuxIno-MICRO, but all other
A20 based boards can be used.
<br/>
'''NOTE:''' See device-tree binding in:
/compile/A20/linux-sunxi/Documentation/devicetree/bindings/net/can/sun4i_can.txt

Modify common device-tree sources:
vi arch/arm/boot/dts/sun7i-a20.dtsi

Append at line 1216:
can0_pins_a: can0@0 {
allwinner,pins = "PH20","PH21";
allwinner,function = "can";
allwinner,drive = <0>;
allwinner,pull = <0>;
};

Append at line 1442:
can0: can@01c2bc00 {
compatible = "allwinner,sun4i-a10-can";
reg = <0x01c2bc00 0x400>;
interrupts = <0 26 4>;
clocks = <&apb1_gates 4>;
status = "disabled";
};

Open arch/arm/boot/dts/sun7i-a20-olinuxino-micro.dts:
vi arch/arm/boot/dts/sun7i-a20-olinuxino-micro.dts

Append at the bottom:
&can0 {
pinctrl-names = "default";
pinctrl-0 = <&can0_pins_a>;
status = "okay";
};

Build everything needed:
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 zImage dtbs modules

Copy kernel, module and dtb to sd-card

=== CAN bus usage ===
Now when everything is ready we need to start using the CAN bus.

You should see __can0__ device with ifconfig:
ifconfig -a

can0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
NOARP MTU:16 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:51

If you don't make sure that module is loaded:
modprobe sun7i_can

Get some tools:
apt-get install can-utils

Configure can bus
ip link set can0 down
ip link set can0 type can bitrate 100000 triple-sampling on loopback off
ip link set can0 up

Now CAN is set to 100kbps. Connect to some you other can devices.

Send simple message:
cansend can0 5A1#A5

For more infomation about can-utils usage:
http://www.armadeus.com/wiki/index.php?title=CAN_bus_Linux_driver

[[Main_Page]]

← Older revision		Revision as of 08:04, 10 June 2021
Line 26:		Line 26:

	Navigate to <Ok> with "tab" key and save changes with "enter" key. Reboot when prompted.		Navigate to <Ok> with "tab" key and save changes with "enter" key. Reboot when prompted.
		+
		+	When done refer further below to [https://www.olimex.com/wiki/A20-CAN#CAN_bus_usage CAN bus usage]

	== Building Linux with CAN support ==		== Building Linux with CAN support ==

← Older revision		Revision as of 08:01, 10 June 2021
Line 20:		Line 20:

	[*] sun7i-a20-can.dtbo Enable CAN controller		[*] sun7i-a20-can.dtbo Enable CAN controller
		+
		+	sun7i-a20-can-pa.dtbo sets pins "PA16", "PA17"
		+
		+	sun7i-a20-can.dtbo sets pins "PH20", "PH21"

	Navigate to <Ok> with "tab" key and save changes with "enter" key. Reboot when prompted.		Navigate to <Ok> with "tab" key and save changes with "enter" key. Reboot when prompted.

@@ Line 13: / Line 13: @@
 Run the built-in script:
-olinuxino-overlay
+  olinuxino-overlay
 Navigate down and enable with "space" key either "sun7i-a20-can-pa.dtbo" or "sun7i-a20-can.dtbo" depending on which port the A20-CAN is connected:
-[ ] sun7i-a20-can-pa.dtbo             Enable CAN controller on PA
+  [ ] sun7i-a20-can-pa.dtbo             Enable CAN controller on PA
 [*] sun7i-a20-can.dtbo                Enable CAN controller
 Navigate to <Ok> with "tab" key and save changes with "enter" key. Reboot when prompted.

@@ Line 7: / Line 7: @@
 *Power LED
 *PCB dimensions: 60x30mm
 == Building Linux with CAN support ==

@@ Line 1: / Line 1: @@
 [[File:A20-CAN.jpeg]]
-[https://www.olimex.com/Products/OLinuXino/Accessories/A20-CAN/ A20-CAN] is CAN driver board for A20 Allwinner SOCs. A20-CAN features are:
+[https://www.olimex.com/Products/OLinuXino/A20/A20-CAN/open-source-hardware A20-CAN] is CAN driver board for A20 Allwinner SOCs. A20-CAN features are:
 *compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB
 *connects to GPIO3 connector

A20-CAN - Revision history

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

LubOlimex: /* Enabling A20-CAN in Olimage Linux */

LubOlimex at 07:56, 10 June 2021

LubOlimex at 11:52, 18 July 2018

Olimex at 06:46, 24 May 2016

Olimex: Created page with "File:A20-CAN.jpeg A20-CAN features: *compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB *connects to GPIO3 connector *allow CAN ne..."

Olimex: Created page with "File:A20-CAN.jpeg A20-CAN features: compatible with A20-OLinuXino-LIME, A20-OLinuXino-LIME2, A20-OLinuXino-MICRO, A20-SOM-EVB connects to GPIO3 connector *allow CAN ne..."