Since I upgraded my Raspberry Pi to the 3.18.8 K my 1-wire system is broken. Just went to 3.18.9 and same problem.
Its all about the new Device Tree stuff. I need to load kernel mods w1_gpio (and w1_therm). The default situation, that is out of the box config.txt, load apparently with out errors but are not functional. In particular, we cannot see /sys/bus/w1/devices/w1_bus_master1.
So, googling around, now need to tell system, via config.txt I want to use 1-wire. Cool, Arch's config.txt seems to have provided necessary config options, uncomment -
$this->bbcode_second_pass_code('', 'device_tree_overlay=w1-gpio-pullup
device_tree_param=gpiopin=4
device_tree_param=pullup=on
device_tree_param=extpullup=5')
and reboot. Now I do see /sys/bus/w1/devices/w1_bus_master1 but no files there representing the temp sensors I use. And, in dmesg I see -
$this->bbcode_second_pass_code('', '[ 8.869662] Driver for 1-wire Dallas network protocol.
[ 8.903004] w1-gpio onewire@0: gpio pin 4, external pullup pin 5, parasitic power 1
[ 8.942929] w1_add_master_device: set_pullup requires write_byte or touch_bit, disabling')
This really has nothing to do with the hardware I have connected, see same error message on another 'Pi with no hardware attached.
Any suggestions ?
David