On Mar 5, 2021, at 9:55 AM, Piotr Barszczewski <piotr@1am.pl> wrote:

Hello,

I'm writing an application for nrf52832 based board ADC + voltage divider functionalty as in the great nRF battery example https://docs.zephyrproject.org/latest/samples/boards/nrf/battery/README.html. I'm adapting it to support multiple vbatt nodes from DTS and while on the code layer it's quite simple I'm struggling with the DTS.

My board dts file contains this part:

#include <nordic/nrf52832_qfaa.dtsi>
/ {
model = "vendor my_board";
compatible = nordic,nrf52832-qfaa","nordic,nrf52832";
// ...
vbatt {
vbatt_lipo: vbatt0 {
compatible = "voltage-divider";
io-channels = <&adc 6>; /* P0.30 = AIN6 */
output-ohms = <3300000>;
full-ohms = <(3300000 + 4700000)>;
status = "okay";
};
vbatt_cr: vbatt1 {
compatible = "voltage-divider";
io-channels = <&adc 1>; /* P0.03 = AIN1 */
output-ohms = <3300000>;
full-ohms = <(3300000 + 4700000)>;
status = "okay";
};
};
// ...
};

The devicetree snippet seems ok

/* Existence and alternate IDs: */
#define DT_N_S_vbatt_S_vbatt0_EXISTS 1
#define DT_N_INST_0_voltage_divider DT_N_S_vbatt_S_vbatt0
#define DT_N_NODELABEL_vbatt_lipo DT_N_S_vbatt_S_vbatt0

except for the DT_N_S_vbatt_S_vbatt0 which is not defined anywhere and as a result I'm getting:

That looks normal.

zephyr/include/devicetree.h:73:17: error: 'DT_N_S_vbatt_S_vbatt_lipo' undeclared here (not in a function); did you mean 'DT_N_S_vbatt_S_vbatt_lipo_ORD'?

What does the code you are building look like?

What else should I do to make my own DTS node be usable in the source file? I'm following the docs, referencing it by #define VBATT_LIPO DT_PATH(vbatt, vbatt_lipo) which is in line with the guides and docs but the DT_N_S_* is missing and I don't have a clue on how could I fix this.
Did anyone experience this before and could point me to where I could find a solution? Been trying for days now without result.

I think the .dts you have looks reasonable, my guess is the issue is more on the code usage side.

Your define of VBATT_LIPO will give you a node reference which by its self is not useful. Its useful only w/regards to the macros in include/devicetree.h

If you can share a snip of what the code looks like will probably be easier to see what might be the issue.

- k