Date: Sat, 5 Jan 2019 11:58:08 -0800 From: Oleksandr Tymoshenko <gonzo@bluezbox.com> To: Per Hedeland <per@hedeland.org> Cc: freebsd-arm@freebsd.org Subject: Re: i2c on RPi Zero? Message-ID: <20190105195808.GA53872@bluezbox.com> In-Reply-To: <dc9441e2-9858-989e-a135-3ae37de0925b@hedeland.org> References: <229e0d36-a07b-8551-9613-0bf5748352e7@hedeland.org> <dc9441e2-9858-989e-a135-3ae37de0925b@hedeland.org>
next in thread | previous in thread | raw e-mail | index | archive | help
Per Hedeland (per@hedeland.org) wrote:
> I did a bit more testing on the Zero to see if the FreeBSD version
> mattered:
>
> FreeBSD-12.0-STABLE-arm-armv6-RPI-B-20190103-r342709.img - still no
> luck.
>
> FreeBSD-11.2-STABLE-arm-armv6-RPI-B-20190103-r342709.img - works!
> (I.e. dmesg reports as below and /dev/iic{0,1} get created - I haven't
> tested actual usage beyond having 'i2c -s' report "no devices found".)
>
> I guess that the i2c support hasn't been removed intentionally,
> i.e. this seems to be a regression - or is there some additional
> config etc required to enable it with FreeBSD-12? The iic and iicbus
> drivers appear to be built into the kernel in both 11 and 12.
>
> (I haven't tested FreeBSD-12 on the Pi B, but I would guess that the
> result will be the same as on the Zero, since it seems the hardware is
> the same.)
There was a transition in device tree files between 11 and 12.
bcm2708-rpi-0-w.dtb has i2c nodes but they're disabled by default.
Try editing config.txt on FAT partition and adding following line:
dtparam=i2c
This should make boot firmware to enable device nodes in the device
tree blob during the boot.
--
gonzo
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20190105195808.GA53872>