Can't read from gpio

[kruenheck]

Trying to read button 3 on the npm1300-ek, which is gpio 1 according to the schematic. The following #defines represent the gpio related registers on the npm1300:

#define GPIOS_MSB         0x06                     // GPIO registers MSB=0x600, individual registers below are added to this 

#define GPIO_MODE1      0x01                     // mode for gpio one (pin)

#define GPIO_STATUS_LOWER    0x1e       // gpio status (all five pins)

I verified that gpio 1 is set to an input using the following:

uint8_t regsy[] = {GPIOS_MSB, GPIO_MODE1};                            

ret = i2c_write_read_dt(&dev_i2c_pmic, regsy, 2, &valRead, 1); 

valRead came back zero indicating to me that the pin is an input

But when I press the button and read the inputs with the following:

uint8_t regsy[] = {GPIOS_MSB, GPIO_STATUS_LOWER};                            

ret = i2c_write_read_dt(&dev_i2c_pmic, regsy, 2, &valRead, 1); 

valRead comes back zero, indicating that the button hasn't affected the pin (it's also zero when the button isn't pressed)

Note that I can perform a write/read to an adc register and get the correct value back, so i2c should be working.

What am I missing?

[Vidar Berg]

Hello,

I did not get around to testing this today, but we have a sample demonstrating how you can use the Zephyr GPIO driver API with the PMIC here: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/pmic/native/npm13xx_one_button/README.html. Have you tried this already? 

The PMIC GPIO driver/shim can be found here: https://github.com/nrfconnect/sdk-zephyr/blob/main/drivers/gpio/gpio_npm13xx.c 

Best regards,

Vidar

[kruenheck]

Vidar,

I don't know what I'm supposed to do with a PMIC GPIO driver/shim.

I tried the npm13xx_one_button sample, but I'm not seeing the callback event (I put a printk() in

event_callback()).

I'm not testing the battery at this point, just trying to see a button, so I didn't set any of the jumpers mentioned in the readMe. But I did make the following connections:

SDA	P0.26
SCL	P0.27
GPIO3	P0.04
VDDIO	VDD
GND	GND

Without adding the npm1300.overlay or the Extra CMake argument, I see "PMIC device ok" (but no call back). However, when I add either the overlay or the cmake argument, I get "Error: led device is not ready"

I'm not sure where to go from here

[Vidar Berg]

Hi,

Please try the modified version of this sample that I’ve included below. The zip also includes the changes I made (a diff), screenshot of build configuration and expected log output, and the hex file from my build.

npm13xx_two_button.zip

Note: it seems that sometimes after power up, you have to press Button 3 on the DK first before it can detect any GPIO events from the PMIC. I’ll discuss this issue with the developers.

[kruenheck]

Vidar,

Thank you for the effort you put into this, but I can't seem to build what you sent me. In npm1300.overlay, I needed to change 

#include <dt-bindings/regulator/npm13xx.h>

to 
#include <dt-bindings/regulator/npm1300.h>

But now I'm getting another error in npm1300.overlay. Here's the output:

-- west build: generating a build system
Loading Zephyr default modules (Zephyr base).
-- Application: C:/myNordic/fromDevZone/npm13xx_two_button
-- CMake version: 3.21.0
-- Found Python3: C:/ncs/toolchains/0b393f9e1b/opt/bin/python.exe (found suitable version "3.12.4", minimum required is "3.10") found components: Interpreter
-- Cache files will be written to: C:/ncs/v3.0.2/zephyr/.cache
-- Zephyr version: 4.0.99 (C:/ncs/v3.0.2/zephyr)
-- Found west (found suitable version "1.2.0", minimum required is "0.14.0")
-- Board: nrf52833dk, qualifiers: nrf52833
-- Found host-tools: zephyr 0.17.0 (C:/ncs/toolchains/0b393f9e1b/opt/zephyr-sdk)
-- Found toolchain: zephyr 0.17.0 (C:/ncs/toolchains/0b393f9e1b/opt/zephyr-sdk)
-- Found Dtc: C:/ncs/toolchains/0b393f9e1b/opt/bin/dtc.exe (found suitable version "1.4.7", minimum required is "1.4.6")
-- Found BOARD.dts: C:/ncs/v3.0.2/zephyr/boards/nordic/nrf52833dk/nrf52833dk_nrf52833.dts
-- Found devicetree overlay: npm1300.overlay
devicetree error: ./npm1300.overlay:10 (column 1): parse error: undefined node label 'npm1300_ek_ldo1'
CMake Error at C:/ncs/v3.0.2/zephyr/cmake/modules/dts.cmake:305 (execute_process):
execute_process failed command indexes:

1: "Child return code: 1"

Call Stack (most recent call first):
C:/ncs/v3.0.2/zephyr/cmake/modules/zephyr_default.cmake:133 (include)
C:/ncs/v3.0.2/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:66 (include)
C:/ncs/v3.0.2/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:92 (include_boilerplate)
CMakeLists.txt:8 (find_package)

-- Configuring incomplete, errors occurred!
←[91mFATAL ERROR: command exited with status 1: 'C:\ncs\toolchains\0b393f9e1b\opt\bin\cmake.EXE' -DWEST_PYTHON=C:/ncs/toolchains/0b393f9e1b/opt/bin/python.exe '-Bc:\myNordic\fromDevZone\npm13xx_two_bu
tton\build' -GNinja -DBOARD=nrf52833dk/nrf52833 -DEXTRA_DTC_OVERLAY_FILE=npm1300.overlay '-Sc:\myNordic\fromDevZone\npm13xx_two_button'
←[0m
* The terminal process terminated with exit code: 1.
* Terminal will be reused by tasks, press any key to close it.

Thank you

[Vidar Berg]

Sorry, I forgot to specify that I was testing against nrf connect sdk version 3.1.x and there looks to be some naming changes between these 2 sdk releases. Are you able to try with this SDK version too? I can also backport my changes if needed. 

[kruenheck]

Vidar,

I upgraded to 3.1.1 and the code builds. It also runs but not very well. When it boots up, it says: Button state (PMIC GPIO2): pressed. I'm surprised by GPIO2 because I'm connected to GPIO3 on the pmic. Also, your screenshot says 'released' on bootup while mine says 'pressed'.

In addition, I have the following issues:

1. I see 'led device not ready' errors quite frequently. The fix seems to be power-cycling the pmic. I haven't put a scope on the i2c lines, but they should be ok because my other apps work.

2. It takes a long time between button presses and any activity in the software. Sometimes I get nothing, and other times I'll get 'Short press' after many seconds (like half a minute). 

3. I never see 'switched 4 pressed'. It always says 'Short press', no matter how long I press the button.

Any ideas as to what's going on?

Thank you

[Vidar Berg]

Hi,

I discussed this issue with one of the developers who pointed out the importance of following the connections outlined in the Wiring section. The jumper placements must be the same as the default placement except for the one on P18 as highlighted below. 

Another issue is that I had not enabled the internal pull-up on GPIO2. This can be fixed in the npm1300.overlay:

&npm1300_ek_buttons {
	pmic_button2: pmic_button_2 {
        gpios = < &npm1300_ek_gpio 2 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
	    label = "Pmic button switch 2";
		zephyr,code = <INPUT_KEY_2>;
	};
};

We will look into adding a picture of the EK with the correct jumper placements for this sample.

Best regards,

Vidar

[kruenheck]

It works now, thank you very much!