Which peripheral chip is used the Banana Pi M2 Berry?

[Kovács Gábor]

Hello,

 

In a GOLANG based, RPi 3B+ project I am using the https://github.com/stianeikeland/go-rpio package to read the state of the GPIO-s. I am planning to set up some Banana Pi M2 Berries with the same software. The package - as it was expected - doesn't work with the M2 Berry. I could adapt the package for the Berry, but I don't know which peripheral chip is used in it. Does anyone know which peripheral chip is used in the Berry? (The schematic diagram on BPI's page is useless).

 

Thanks,

 

G.

[kerel]

Hi!

 

Most consistent interface to GPIO across different devices is probably the sysfs gpio interface (yes, deprecated, but very widely used).

 

sinovoip published a patched fork of Wiring Pi for all their Banana Pi products: BPI-WiringPi2 (deep link to: pin mappings for the m2u).

Wiring Pi is built around the sysfs gpio interface.

 

A usage guide was published here: https://forum.banana-pi.org/t/how-to-get-working-wiringpi-on-raspbian/3696

An additional step for armbian users might be needed: https://forum.banana-pi.org/t/banana-pi-bpi-m2-ultra-m2u-wiringpi-gpio-demo/3027/10

 

Then, using e.g. the go-wiringpi bindings you should be able to use the M2berry GPIOs in golang.

 

I did not try any of the steps above but hope that at least some of it will help you.

Let us know of your results!

 

Sincerely,

kerel

 

PS: New userspace applications are supposed to use the character device GPIO, see https://lloydrochester.com/post/hardware/libgpiod-intro-rpi/

Go library: https://github.com/warthog618/gpiod

 

I can confirm that there are 288 lines exposed via this new interface:

 

root@m2berry:~# gpiodetect 
gpiochip0 [1c20800.pinctrl] (288 lines)

 

 

Device Tree:

Spoiler

root@m2berry:~# dtc -I fs -O dts /sys/firmware/devicetree/base > /tmp/mydts
root@m2berry:~# cat /tmp/mydts
[...]
	pinctrl@1c20800 {
			vcc-pf-supply = <0x15>;
			compatible = "allwinner,sun8i-r40-pinctrl";
			clocks = <0x02 0x4f 0x21 0x22 0x00>;
			vcc-pe-supply = <0x26>;
			clock-names = "apb\0hosc\0losc";
			gpio-controller;
			vcc-pd-supply = <0x15>;
			#interrupt-cells = <0x03>;
			interrupts = <0x00 0x1c 0x04>;
			vcc-pc-supply = <0x15>;
			phandle = <0x16>;
			reg = <0x1c20800 0x400>;
			#gpio-cells = <0x03>;
			pinctrl-0 = <0x24>;
			vcc-pa-supply = <0x25>;
			vcc-pg-supply = <0x19>;
			pinctrl-names = "default";
			interrupt-controller;

			can-ph-pins {
				pins = "PH20\0PH21";
				function = "can";
			};

			mmc1-pg-pins {
				pins = "PG0\0PG1\0PG2\0PG3\0PG4\0PG5";
				drive-strength = <0x1e>;
				phandle = <0x17>;
				function = "mmc1";
				bias-pull-up;
			};

			uart3-rts-cts-pg-pins {
				pins = "PG8\0PG9";
				phandle = <0x2c>;
				function = "uart3";
			};

			i2c4-pins {
				pins = "PI2\0PI3";
				phandle = <0x32>;
				function = "i2c4";
			};

			can-pa-pins {
				pins = "PA16\0PA17";
				function = "can";
			};

			mmc2-pins {
				pins = "PC5\0PC6\0PC7\0PC8\0PC9\0PC10\0PC11\0PC12\0PC13\0PC14\0PC15\0PC24";
				drive-strength = <0x1e>;
				phandle = <0x1b>;
				function = "mmc2";
				bias-pull-up;
			};

			i2c3-pins {
				pins = "PI0\0PI1";
				phandle = <0x31>;
				function = "i2c3";
			};

			i2c2-pins {
				pins = "PB20\0PB21";
				phandle = <0x30>;
				function = "i2c2";
			};

			mmc0-pins {
				pins = "PF0\0PF1\0PF2\0PF3\0PF4\0PF5";
				drive-strength = <0x1e>;
				phandle = <0x14>;
				function = "mmc0";
				bias-pull-up;
			};

			gmac-rgmii-pins {
				pins = "PA0\0PA1\0PA2\0PA3\0PA4\0PA5\0PA6\0PA7\0PA8\0PA10\0PA11\0PA12\0PA13\0PA15\0PA16";
				drive-strength = <0x28>;
				phandle = <0x33>;
				function = "gmac";
			};

			i2c1-pins {
				pins = "PB18\0PB19";
				phandle = <0x2f>;
				function = "i2c1";
			};

			clk-out-a-pin {
				pins = "PI12";
				phandle = <0x24>;
				function = "clk_out_a";
			};

			i2c0-pins {
				pins = "PB0\0PB1";
				phandle = <0x2d>;
				function = "i2c0";
			};

			uart0-pb-pins {
				pins = "PB22\0PB23";
				phandle = <0x2a>;
				function = "uart0";
			};

			ir1-pins {
				pins = "PB23";
				phandle = <0x28>;
				function = "ir1";
			};

			uart3-pg-pins {
				pins = "PG6\0PG7";
				phandle = <0x2b>;
				function = "uart3";
			};

			mmc3-pins {
				pins = "PI4\0PI5\0PI6\0PI7\0PI8\0PI9";
				drive-strength = <0x1e>;
				phandle = <0x1c>;
				function = "mmc3";
				bias-pull-up;
			};

			ir0-pins {
				pins = "PB4";
				phandle = <0x27>;
				function = "ir0";
			};
		};