Hi!
I’m trying to forward port some stuff to latest uboot and kernel. Part of it relies on Dallas 1Wire. But I can’t seem to get devices to appear on the bus. Here’s what I’ve done
Ensure have the latest overlays
$ git clone https://github.com/BeagleBoard/bb.org-overlays.git
$ cd bb.overlays
$ ./install.sh
$cat /boot/uEnv
uname_r=4.19.25-ti-r16
enable_uboot_overlays=1
disable_uboot_overlay_emmc=1
disable_uboot_overlay_video=1
disable_uboot_overlay_audio=1
disable_uboot_overlay_wireless=1
disable_uboot_overlay_adc=1
enable_uboot_cape_universal=1
uboot_overlay_addr0=/lib/firmware/BB-W1-P9.12-00A0.dtbo
cmdline=coherent_pool=1M
During boot, everything seems good:
[ 2.781427] Driver for 1-wire Dallas network protocol.
The /sys/bus directory is structured right:
$ ls /sys/bus/w1/
devices drivers drivers_autoprobe drivers_probe uevent
But there’s nothing under devices:
$ ls -la /sys/bus/w1/devices/
total 0
drwxr-xr-x 2 root root 0 Mar 28 13:15 .
drwxr-xr-x 4 root root 0 Jan 1 2000 …
lrwxrwxrwx 1 root root 0 Mar 28 13:15 w1_bus_master1 → …/…/…/devices/w1_bus_master1
I’m confident that my test sensor I have attached is working, as it is correctly being addressed by an Arduino board when I connect it to that (by taking the jumper pins off the BBB and onto the Arduino).
ROM = XX XX XX XX XX XX XX
Chip = DS18B20
Data = 1 3F 1 4B 46 7F FF C 10 F3 CRC=F3
Temperature = 19.94 Celsius, 67.89 Fahrenheit
If someone could confirm that they are currently on 4.19 and can test P9_12 for 1wire and that it is indeed working for them (or not!) it’d be appreciated (I discovered my difficulties back on 4.14 and thought maybe I should try a later kernel…). I’m getting to my wits end here. About the only thing I’ve not fully looked up is whether the 4.7k resistor is needed on the BBB, but from my testing neither works anyway so erm… help please?
Cheers,
Pete.