iic

[Elwood Downey]

Hello all!

Trying IIC on RPi 4b 4GB, no joy yet. Looking for ideas. So far:

   - bus seems to be present based on dmesg and /dev/iic0 (see below)
   - device is BME280 <https://www.adafruit.com/product/2652> env sensor at
   IIC address 0x77.
   - wiki page here <https://wiki.freebsd.org/arm/Raspberry%20Pi> suggests
   it should work.
   - The table says "OK (brcm BSC)" but not sure what that extra bit means.
   - Tried all the kernels mentioned on that page with no luck so decided
   on some 13-BETAs, still no luck.
   - Device is known to work on the same hardware running Raspbian 10
   "buster".
   - tried the I2CRDWR-only test program here
   <https://vzaigrin.wordpress.com/2014/04/28/working-with-i2c-in-freebsd-on-raspberry-pi/>
   but that does not find my device either

Suggestions welcome!

adTHANKSvance

Elwood Downey
Tucson AZ


freebsd at generic:~ % dmesg | grep iic
iichb0: <BCM2708/2835 BSC controller> mem 0x7e804000-0x7e804fff irq 26 on
simplebus0
iicbus0: <OFW I2C bus> on iichb0
iic0: <I2C generic I/O> on iicbus0

freebsd at generic:~ % uname -a
FreeBSD generic 13.0-BETA2 FreeBSD 13.0-BETA2 #0
releng/13.0-n244498-6461715f1ae: Fri Feb 12 06:21:00 UTC 2021
root at releng1.nyi.freebsd.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC
 arm64

freebsd at generic:~ % ls -l /dev/iic0
crw-------  1 root  wheel  0x45 Feb 12 07:01 /dev/iic0

freebsd at generic:~ % sudo i2c -s
Hardware may not support START/STOP scanning; trying less-reliable read
method.
Scanning I2C devices on /dev/iic0: <none found>