1wire DS18b20 on Rock64?

[mcerveny]

Has anyone got DS18b20 to work on rock64?

Yes. Step by step:

1. Hardware setup: I suppose pin12 is unusable (works only as input). Let's make following pin connection setup - rock64 pin1 (3.3V) = DS18B20 pin3 (VDD), rock64 pin7 (GPIO1_D4) = DS18B20 pin2 (DQ), rock64 pin9 (GND) = DS18B20 pin1 (GND) and pullup resistor 4k7 ohm between DS18B20 pin3 and DS18B20 pin2.
   
2. Prepare DTOVERLAY for "w1_gpio" driver association. Let's assume GPIO1_D4 == id 60, GPIO1_D4 == GPIO1 + bit 28.
   
   Code:

   $ cat > w1_pin60.dts << 'EOF' /dts-v1/; /plugin/; / { compatible = "pine64,rock64", "rockchip,rk3328"; fragment@0 { target-path = "/"; __overlay__ { w1: onewire@0 { compatible = "w1-gpio"; pinctrl-names = "default"; pinctrl-0 = <&w1_pins>; gpios = <&gpio1 28 0>; status = "okay"; }; }; }; fragment@1 { target = <&gpio1>; __overlay__ { w1_pins: w1_pins@0 { rockchip,pins = <1 28 0 &pcfg_pull_up>; }; }; }; }; EOF $ dtc -I dts -O dtb -@ w1_pin60.dts -o w1_pin60.dtbo $ ### ignore warnings
3. Successful load of DTOVERLAY depends on your device tree (DTB symbols must be included). Check DTB symbols if exists skip to step 5.
   
   Code:

   $ dtc /boot/dtbs/$(uname -r)/rockchip/rk3328-rock64.dtb -o - 2>/dev/null | grep __symbols__ __symbols__ { $ ### ^^^^ symbols included or not included if no output
4. Symbols are NOT present in latest stable 0.7.9 based on kernel 4.4.132-1075
   So you must rebuild rk3328-rock64.dtb with symbols.
   
   Code:

   $ uname -a Linux rock64 4.4.132-1075-rockchip-ayufan-ga83beded8524 #1 SMP Thu Jul 26 08:22:22 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux $ sudo bash # wget https://github.com/ayufan-rock64/linux-kernel/archive/4.4.132-1075-rockchip-ayufan.tar.gz # tar xzf 4.4.132-1075-rockchip-ayufan.tar.gz # cd linux-kernel-4.4.132-1075-rockchip-ayufan/ # export ARCH=arm64 # make rockchip_linux_defconfig # make DTC_FLAGS="-@" dtbs # mv /boot/dtbs/4.4.132-1075-rockchip-ayufan-ga83beded8524/rockchip/rk3328-rock64.dtb /boot/dtbs/4.4.132-1075-rockchip-ayufan-ga83beded8524/rockchip/rk3328-rock64.dtb_orig # cp arch/arm64/boot/dts/rockchip/rk3328-rock64.dtb /boot/dtbs/4.4.132-1075-rockchip-ayufan-ga83beded8524/rockchip/rk3328-rock64.dtb # reboot # ### after reboot check presented symbols
5. Load DTOVERLAY:
   
   Code:

   $ sudo bash # ### speedup minimum CPU frequency due to polling behavior of w1-gpio # echo 600000 > /sys/devices/system/cpu/cpufreq/policy0/scaling_min_freq # ### load DTOVERLAY # mkdir -p /sys/kernel/config/device-tree/overlays/w1 # cat w1_pin60.dtbo > /sys/kernel/config/device-tree/overlays/w1/dtbo # lsmod | grep w1 w1_gpio 16384 0 wire 32768 1 w1_gpio # find /sys/bus/w1/ /sys/bus/w1/ /sys/bus/w1/devices /sys/bus/w1/devices/w1_bus_master1 /sys/bus/w1/drivers /sys/bus/w1/drivers/w1_master_driver /sys/bus/w1/drivers/w1_master_driver/bind /sys/bus/w1/drivers/w1_master_driver/w1_bus_master1 /sys/bus/w1/drivers/w1_master_driver/uevent /sys/bus/w1/drivers/w1_master_driver/unbind /sys/bus/w1/drivers/w1_slave_driver /sys/bus/w1/drivers/w1_slave_driver/bind /sys/bus/w1/drivers/w1_slave_driver/uevent /sys/bus/w1/drivers/w1_slave_driver/unbind /sys/bus/w1/uevent /sys/bus/w1/drivers_probe /sys/bus/w1/drivers_autoprobe # ### autoprobe should discover sensor after few seconds # find /sys/bus/w1/ /sys/bus/w1/ /sys/bus/w1/devices /sys/bus/w1/devices/w1_bus_master1 /sys/bus/w1/devices/28-000000423711 /sys/bus/w1/drivers /sys/bus/w1/drivers/w1_master_driver /sys/bus/w1/drivers/w1_master_driver/bind /sys/bus/w1/drivers/w1_master_driver/w1_bus_master1 /sys/bus/w1/drivers/w1_master_driver/uevent /sys/bus/w1/drivers/w1_master_driver/unbind /sys/bus/w1/drivers/w1_slave_driver /sys/bus/w1/drivers/w1_slave_driver/bind /sys/bus/w1/drivers/w1_slave_driver/28-000000423711 /sys/bus/w1/drivers/w1_slave_driver/uevent /sys/bus/w1/drivers/w1_slave_driver/unbind /sys/bus/w1/uevent /sys/bus/w1/drivers_probe /sys/bus/w1/drivers_autoprobe # ### check w1 # grep '' /sys/bus/w1/devices/w1_bus_master1/w1_master_slave_count /sys/bus/w1/devices/w1_bus_master1/w1_master_slaves /sys/bus/w1/devices/w1_bus_master1/w1_master_slave_count:1 /sys/bus/w1/devices/w1_bus_master1/w1_master_slaves:28-000000423711 # ### thermal driver automatically loaded # lsmod | grep w1 w1_therm 16384 0 w1_gpio 16384 0 wire 32768 2 w1_gpio,w1_therm # ### read temperature # cat /sys/bus/w1/devices/*/w1_slave 6b 01 4b 46 7f ff 05 10 49 : crc=49 YES 6b 01 4b 46 7f ff 05 10 49 t=22687

Merry Xmas and buy me a Beer.