Re: i2c working on BeagleBone?

[Lwazi Dube <lwazeh%gmail.com@localhost>]

On Sun, 2 Apr 2023 at 21:02, Lwazi Dube <lwazeh%gmail.com@localhost> wrote:
>
> On Sun, 2 Apr 2023 at 06:05, Chris <sekiya%netbsd.org@localhost> wrote:
> >
> > On Sun, Apr 02, 2023 at 11:27:28AM +0200, Radoslaw Kujawa wrote:
> >
> > > I am positive it worked before FDT changes. I remember playing around with various sensors and even testing newly written I2C drivers with the original white BB.
> >
> > Thanks for the confirmation; now I have a better idea what I'm dealing with.
> > What version were you working with, so that I can better bisect the code?
> >
> I just downloaded, built and tried an 8.2 kernel (on BB white). It
> does not detect iic1 until I add this:
> tiiic1        at obio1 addr 0x4802A000 size 0x1000 intr 71
>
> The ti_iic driver silently fails to configure the I2C1 pads. It should
> be looking for "SPI0_CS0" and "SPI0_D1" but is searching for
> "I2C1_SCL" and "I2C1_SDA" instead.
> I will try to fix this and do more testing, but I think it never
> worked unmodified on 8.2. The device tree came in version 9 (See:
> https://netbsd.org/releases/formal-9/NetBSD-9.0.html).
>
> -Lwazi

After fixing the pad configuration in ti_iic.c, I can use ioctl, in an
application, to read the id on an attached sensor.
8.x kernels are probably work if the bootloader configures the i2c pins.