Hi,
Please follow below mentioned steps to enable the CAN interface on i.MX6Q SABRESD board.
- Populate R662 Register to stabilize CANH and CANL output signals.
- Pin connection of CAN interface with i.MX6Q Processor is shown as below.
- CAN_TX:
- CAN_TX signal is connected between i.MX6Q Processor and CAN transceiver pin 1.
- CAN_TX pin is GPIO_7 of P5 port of i.MX6Q Processor.
- CAN_TX pin is defined as MX6QDL_PAD_GPIO_7__FLEXCAN1_TX Macro in i.MX6Q SABRESD Board DTS.
- CAN_RX:
- CAN_RX signal is connected between i.MX6Q Processor and CAN transceiver pin 4.
- CAN_RX pin is GPIO_8 of P5 port of i.MX6Q Processor.
- CAN_RX pin is defined as MX6QDL_PAD_GPIO_8__FLEXCAN1_RX Macro in i.MX6Q SABRESD Board DTS.
- CANL_STBY:
- CAN_STBY signal is connected between i.MX6Q Processor and CAN transceiver pin 8.
- CAN_STBY pin is GPIO_19 of P5 port of i.MX6Q Processor.
- CAN_STBY pin is defined as MX6QDL_PAD_GPIO_19__GPIO4_IO05 Macro in Macro in i.MX6Q SABRESD Board DTS.
- Apply following changes in i.MX6Q SABRESD kernel source DTS file.
| CAN interface Patch |
|---|
| --- a/arch/arm/boot/dts/imx6qdl-sabresd.dtsi +++ b/arch/arm/boot/dts/imx6qdl-sabresd.dtsi @@ -137,6 +137,19 @@ gpio = <&gpio6 14 0>; enable-active-high; }; + + reg_can_xcvr: regulator@6 { + + compatible = "regulator-fixed"; + reg = <5>; + regulator-name = "CAN XCVR"; + regulator-min-microvolt = <3300000>; + regulator-max-microvolt = <3300000>; + pinctrl-names = "default"; + gpio = <&gpio4 5 GPIO_ACTIVE_HIGH>; + enable-active-low; + }; + }; gpio-keys { @@ -608,6 +621,14 @@ interrupt-parent = <&gpio3>; interrupts = <16 1>; }; + + max7310_b: gpio@32 { + compatible = "maxim,max7310"; + reg = <0x32>; + gpio-controller; + #gpio-cells = <2>; + }; + }; &iomuxc { @@ -700,6 +721,16 @@ >; }; + + pinctrl_flexcan1: flexcan1grp { + fsl,pins = < + MX6QDL_PAD_GPIO_7__FLEXCAN1_TX 0x1b0b0 + MX6QDL_PAD_GPIO_8__FLEXCAN1_RX 0x1b0b0 + MX6QDL_PAD_GPIO_19__GPIO4_IO05 0x1b0b0 + >; + }; + + pinctrl_gpio_keys: gpio_keysgrp { fsl,pins = < MX6QDL_PAD_EIM_D29__GPIO3_IO29 0x1b0b0 @@ -1064,3 +1095,11 @@ fsl,wdog_b; status = "okay"; }; + +&can1 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_flexcan1>; + xceiver-supply = <®_can_xcvr>; + status = "okay"; /* pin conflict with fec */ +}; |
After applying these modification, run following commands on i.MX6Q SABRESD Board terminal,
$ ip link set can0 up
$ ip link set can0 type can bitrate 500000
$ cansend can0 123#DEADBEEF
The CAN bus data captured in CAN analyzer between CANH (pin-7) and GND (pin-2) is shown as below:
Regards,
Shivani.
