Fu-.

I want to use Pin #7(GPIOB0) as 1-wire like a RaspberryPi. Drivers(wire,w1-gpio,w1-therm) are loaded. But, Pin #7 does not appear to be working correctly. I modified a little on rk3399-tinker_board_2.dts like this: / { : (SNIPPED) : w1 { compatible = "w1-gpio"; pinctrl-names = "default"; pinctrl-0 = <&w1_pin>; gpios = <&gpio0 RK_PB0 GPIO_ACTIVE_HIGH>; status = "okay"; }; }; &pinctrl { pinctrl-0 = <&gpio_init &test_clkout2 &w1_pin>; : (SNIPPED) : w1pin { w1_pin: w1-pin { rockchip,pins = <RK_GPIO0 RK_PB0 RK_FUNC_3 &pcfg_pull_up>; }; }; }; --- dmesg says, [ 5.245994] Driver for 1-wire Dallas network protocol. No devices detected. gpio readall says Pin#7(GPIO 8) is GPIOB0, NOT CLKOUT. Does anyone know a better way? Regards,

After further investigation, it seems that GPIO#15 (gpio2c_4) is correctly set to pull-down GPIO mode. read GRF_GPIO2C_IOMUX: io -4 -r 0xff77e008 ff77e008: 00000000 bits 9:8 is 2'b00 = GPIO read GRF_GPIO2C_P: io -4 -r 0xff77e048 ff77e048: 0000fd3f bits 9:8 is 2'b01 = weak 0(pull down) Nevertheless, once the input changes from Low->High and the High input is nothing, GPIO#15 continues to stay High. Is there something else I should be setting? From these conditions, it does not seem to be a problem with wiringPi. Is this not a problem with RK3399, but a specification of Tinker2S?

> 4. GPIO #15 (wiring Pi #3) pulled down <-> up switch How to do this?

Hmm... The value remains latched even when the input of GPIO#84 is manipulated directly (once Low->High and then High input is turned off, the value remains High).

I found and wrote into /boot/config.txt; gpio=84=ip,pd but this doesn't make any sense. I did notice one odd thing. Looking directly at GPIO#15 (pin No.84), the value seems to be changing correctly with no input (but I had to change active_low to 1 as follows). # echo 84 > /sys/class/gpio/export # cd /sys/class/gpio/export/gpio84 # cat active_low 0 # echo 1 > active_low # cat value 0 Also, # cat/sys/kernel/debug/pinctrl/pinctrl/pinmux-pins 　　　: pin 84 (gpio2-20): (MUX UNCLAIMED) gpio2:84 　　　: It doesn't look like the multiplexer is selecting a GPIO. Does wiringPi correctly select Func_1(gpio2_c[4])?

Thanks Joe, Result is this: --- linaro@linaro-alip:~$ gpio readall +-----+-----+---------+------+---+--Tinker--+---+------+---------+-----+-----+ | CPU | wPi | Name | Mode | V | Physical | V | Mode | Name | wPi | CPU | +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+ | | | 3.3v | | | 1 || 2 | | | 5v | | | | 73 | 8 | GPIO2B1 | IN | 1 | 3 || 4 | | | 5v | | | | 74 | 9 | GPIO2B2 | IN | 1 | 5 || 6 | | | 0v | | | | 8 | 7 | GPIO0B0 | IN | 0 | 7 || 8 | 1 | IN | GPIO2C1 | 15 | 81 | | | | 0v | | | 9 || 10 | 1 | IN | GPIO2C0 | 16 | 80 | | 83 | 0 | GPIO2C3 | IN | 1 | 11 || 12 | 0 | IN | GPIO3D0 | 1 | 120 | | 85 | 2 | GPIO2C5 | IN | 0 | 13 || 14 | | | 0v | | | | 84 | 3 | GPIO2C4 | IN | 1 | 15 || 16 | 0 | IN | GPIO2C6 | 4 | 86 | | | | 3.3v | | | 17 || 18 | 0 | IN | GPIO2C7 | 5 | 87 | | 40 | 12 | GPIO1B0 | IN | 1 | 19 || 20 | | | 0v | | | | 39 | 13 | GPIO1A7 | IN | 1 | 21 || 22 | 0 | IN | GPIO3D4 | 6 | 124 | | 41 | 14 | GPIO1B1 | IN | 1 | 23 || 24 | 1 | IN | GPIO1B2 | 10 | 42 | | | | 0v | | | 25 || 26 | 0 | IN | GPIO0A6 | 11 | 6 | | 71 | 30 | GPIO2A7 | IN | 1 | 27 || 28 | 1 | IN | GPIO2B0 | 31 | 72 | | 126 | 21 | GPIO3D6 | IN | 0 | 29 || 30 | | | 0v | | | | 125 | 22 | GPIO3D5 | IN | 0 | 31 || 32 | 0 | IN | GPIO4C2 | 26 | 146 | | 150 | 23 | GPIO4C6 | OUT | 1 | 33 || 34 | | | 0v | | | | 121 | 24 | GPIO3D1 | IN | 0 | 35 || 36 | 1 | IN | GPIO2C2 | 27 | 82 | | 149 | 25 | GPIO4C5 | IN | 0 | 37 || 38 | 0 | IN | GPIO3D3 | 28 | 123 | | | | 0v | | | 39 || 40 | 0 | IN | GPIO3D7 | 29 | 127 | +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+ | CPU | wPi | Name | Mode | V | Physical | V | Mode | Name | wPi | CPU | +-----+-----+---------+------+---+--Tinker--+---+------+---------+-----+-----+ Even though there is no input to GPIO#15, it is high.

Thanks Joe, I tried your sample, but I still have problems. A High is input to GPIO#15 once, and the original value is maintained even when the input is released. I want GPIO#15 to go Low when the input is released. Any solution?

I wrote and test this dts; ----- /dts-v1/; /plugin/; / { compatible = "rockchip,rk3399"; /* disable spi5 */ fragment@0 { target = <&spi5>; __overlay__ { status = "okay"; spi5 { status = "disabled"; }; }; }; fragment@1 { target-path = "/"; __overlay__ { gpio15 { compatible = "gpio2"; pinctrl-names = "default"; pinctrl-0 = <&gpio_pins>; gpios = <&gpio2 20 0>; status = "okay"; }; }; }; fragment@2 { target = <&gpio2>; __overlay__ { gpio_pins: gpio_pins { rockchip,pins = <2 20 0 &pcfg_pull_down>; }; }; }; }; ----- However, this did not work. It still behaves as if it is latching.

Hi, I want to use wiringPi on Tinker2S. I'm trying to use GPIO Pin#15 (wiring Pi Pin#3) as a pull-down input, but after a bit of research, it seems to be acting like it's latching. Once the Input goes High, the input does not drop to Low after that. Is there a good solution?