Enable 1-wire in DeviceTree for iMX6 DualLite

[mrtex]

Hello,

im trying to enable 1-wire support to read out a DS18B20 Temperature Sensor.

The following were added in the .dtsi:

onewire {

compatible = "w1-gpio";

gpios = <&gpio1 21 GPIO_ACTIVE_HIGH>;

linux,open-drain;

pinctrl-names = "default";

pinctrl-0 = <&pinctrl_onewire>;

status = "okay";

};

pinctrl_onewire: onewire {

fsl,pins = <

MX6QDL_PAD_SD1_DAT3__GPIO1_IO21 0x1b0b1

>;

};

Kernel Modules are loaded.

I just getting messages like this:

[ 11.088682] w1_master_driver w1_bus_master1: w1_search: max_slave_count 64 reached, will continue next search.

[ 58.514767] w1_master_driver w1_bus_master1: Family 0 for 00.800000000000.8c is not registered.

[ 117.844374] w1_master_driver w1_bus_master1: Family 0 for 00.400000000000.46 is not registered.

[ 165.214311] w1_master_driver w1_bus_master1: Family 0 for 00.c00000000000.ca is not registered.

[ 236.484191] w1_master_driver w1_bus_master1: Family 0 for 00.200000000000.23 is not registered.

[ 295.805318] w1_master_driver w1_bus_master1: Family 0 for 00.a00000000000.af is not registered.

I have already tried different things but nothing helped. Im sure that i connected the correct Pin and the Sensor is also correct wired. Of course with a 4K7 resistor.

Does anyone have a suggestion?

I'm not sure about the 0x1b0b1 descriptor or using MX6QDL_PAD_SD1_DAT3__GPIO1_IO21 instead of MX6QDL_PAD_SD1_DAT3__SD1_DATA3

Thank you in advice

[igorpadykov · Accepted solution]

Hi Christian

for open drain register IOMUXC_SW_PAD_CTL_PAD_SD3_DATA3

should set bit 11, ODE=1 this corresponds to 0x1a8b1 descriptor.

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[mrtex]

Hi Igor,

that doesn't work so far but i figured out that 0x4001b8b1 will work. That's the same value wich is be used for i2c in the DeviceTree.

Thank you very much for your help. =)