• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 98 subscribers
  • Views 557 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

AM5728 i2c read error

AM5728: AM5728 i2c read error

Gowtham BN83
Prodigy 40 points

Part Number: AM5728
Other Parts Discussed in Thread: TMP108, TMP102

Hi, I am facing exactly the same issue with the I2C2 bus on our custom board. We have connected a small temperature sensor - TMP108 on this particular bus. When I try to read the address of the sensor, am not getting any value.

But when I try the same from an external I2C analyzer (AARDVARK), I am able to communicate to the temperature sensor successfully & read its address. Appreciate your quick response on this.

Regards,

Gowtham

  • 0
    TI__Guru**** 393215 points
    Please post the Linux version you use, I2C pinmux and device tree settings.
  • 0 in reply to Biser Gatchev-XID
    Prodigy 40 points
    Thanks Biser, pls find the details here:

    Linux Version-4.4


    Pinmux & Device tree settings as below

    i2c2_pins_default: i2c2_pins_default {
    pinctrl-single,pins = <
    0x408 (PIN_INPUT_PULLUP | MUX_MODE0) /* gpmc_a0.i2c4_scl */
    0x40c (PIN_INPUT_PULLUP | MUX_MODE0) /* gpmc_a1.i2c4_sda */
    >;
    };

    i2c2_pins_sleep: i2c2_pins_sleep {
    pinctrl-single,pins = <
    0x408 (PIN_INPUT | MUX_MODE15)
    0x40c (PIN_INPUT | MUX_MODE15)
    >;
    };

    &i2c2 {
    status = "okay";
    pinctrl-names = "default";
    pinctrl-0 = <&i2c2_pins_default>;
    pinctrl-1 = <&i2c2_pins_sleep>;
    clock-frequency = <400000>;

    Regards,
    Gowtham
  • 0 in reply to Gowtham BN83
    TI__Guru**** 170625 points
    Gowtham,

    AM572x TI EVM comes with TMP102 temperature sensor, see below e2e threads for details how to use it:

    e2e.ti.com/.../743037

    If you need to use TMP108 sensor, you can check how TMP102 is enabled in kernel and reuse the same approach. Check below pointers:

    linux-4.x/arch/arm/boot/dts/am57xx-beagle-x15-common.dtsi

    linux-4.x/arch/arm/configs/tisdk_am57xx-evm_defconfig

    linux-4.x/Documentation/devicetree/bindings/hwmon/tmp108.txt
    linux-4.x/Documentation/hwmon/tmp108

    Regards,
    Pavel
  • 0 in reply to Pavel Botev
    TI__Guru**** 170625 points
    If you have no more questions related to the subject, please close/verify/resolve this thread.

    Regards,
    Pavel