Re: Orange pi support for i2c

[Tobias Nygren <tnn%NetBSD.org@localhost>]

On Sat, 07 Aug 2021 21:54:40 +0000
Dave Tyson <dtyson%anduin.org.uk@localhost> wrote:

> The Banana pi seems to work OK with i2c with light testing, but I would really 
> like a more 'lightweight' platform like the Orange pi zero or Orange pi one. 
> Under a recent current both these boot up OK, but there doesn't appear to be 
> any support for i2c - how hard would that be to add?

Already supported -- but you need to enable the i2c nodes in the device tree
with a dtb overlay. It will be something like below. You'll have to consult
the data sheet to see if any of the respective i2c controller's pins are used
for conflicting purposes.

--- sys/arch/arm/dts/sun8i-h3-orangepi-one.dts  30 Nov 2017 21:39:35 -0000      1.3
+++ sys/arch/arm/dts/sun8i-h3-orangepi-one.dts  7 Aug 2021 21:47:46 -0000
@@ -29,3 +29,12 @@
 #include "../../../external/gpl2/dts/dist/arch/arm/boot/dts/sun8i-h3-orangepi-one.dts"
 #include "sun8i-h3.dtsi"

+&i2c0 {
+        status = "okay";
+};
+&i2c1 {
+        status = "okay";
+};
+&i2c2 {
+        status = "okay";
+};