Re: [PATCH v3 1/2] ARM: dts: imx51-eukrea-mbimxsd51-baseboard: Add CAN support

[Alexander Shiyan]

Tue, 6 May 2014 09:56:37 -0300 от Fabio Estevam <fabio.estevam at freescale.com>:
> Add support for CAN based on a MPC2515 connected to ECSPI1.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Changes since v2:
> - None
> Changes since v1:
> - Use active low for spi chipselect
> - Remove unused GPIOs for CAN
> 
>  .../boot/dts/imx51-eukrea-mbimxsd51-baseboard.dts  | 28 ++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/imx51-eukrea-mbimxsd51-baseboard.dts b/arch/arm/boot/dts/imx51-eukrea-mbimxsd51-baseboard.dts
> index 8b1098e..c8ad934 100644
> --- a/arch/arm/boot/dts/imx51-eukrea-mbimxsd51-baseboard.dts
> +++ b/arch/arm/boot/dts/imx51-eukrea-mbimxsd51-baseboard.dts
> @@ -86,6 +86,23 @@
>  	status = "okay";
>  };
>  
> +&ecspi1 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_ecspi1>;
> +	fsl,spi-num-chipselects = <1>;
> +	cs-gpios = <&gpio4 24 GPIO_ACTIVE_LOW>;
> +	status = "okay";
> +
> +	can0: can at 0 {
> +		compatible = "microchip,mcp2515";
> +		reg = <0>;
> +		clocks = <&clks IMX5_CLK_OSC>;

I would recommend using a separate fixed clock for this, if not actually OSC
frequency is used. Eric?

> +		spi-max-frequency = <1000000>;
> +		interrupt-parent = <&gpio1>;
> +		interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
> +	};
> +};
> +
>  &i2c1 {
>  	tlv320aic23: codec at 1a {
>  		compatible = "ti,tlv320aic23";
> @@ -104,6 +121,17 @@
>  			>;
>  		};
>  
> +		pinctrl_ecspi1: ecspi1grp {
> +			fsl,pins = <
> +				MX51_PAD_CSPI1_MISO__ECSPI1_MISO	0x185
> +				MX51_PAD_CSPI1_MOSI__ECSPI1_MOSI	0x185
> +				MX51_PAD_CSPI1_SCLK__ECSPI1_SCLK	0x185
> +				MX51_PAD_CSPI1_SS0__GPIO4_24		0x80000000 	/* CS0 */
> +				MX51_PAD_CSI2_PIXCLK__GPIO4_15		0x80000000	/* nReset */
> +				MX51_PAD_GPIO1_1__GPIO1_1		0x80000000	/* IRQ */
> +			>;

eCSPI should be a separate group, ie without nReset and IRQ.

nReset is means nothing here. You should add a fixed regulator
for this pin and use it as "vdd-supply" for CAN chip. (Active high).

---