voxl_spi_init, failed to open /dev/spidev device: No such file or directory.

[admin]

Hi @이광철 ,

We defaulted this interface to SPI starting in SDK 1.1.2.

VOXL 2 Mini Linux User Guide

ModalAI technical documentation for VOXL and VOXL 2 Companion Computers for PX4 and ArduPilot Obstacle Avoidance and GPS-denied navigation, assembled in the USA

ModalAI Technical Docs (docs.modalai.com)

VOXL 2/VOXL2 Mini System Image

ModalAI technical documentation for VOXL and VOXL 2 Companion Computers for PX4 and ArduPilot Obstacle Avoidance and GPS-denied navigation, assembled in the USA

ModalAI Technical Docs (docs.modalai.com)

It can be converted back to SPI with a kernel change and rebuild if you are able to try that.
https://docs.modalai.com/voxl2-kernel-build-guide/

Enable:
https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/blob/qrb5165-ubun1.0-14.1a/recipes-kernel/linux-msm/files/dts/m0104/m0104-modalai-qupv3.dtsi?ref_type=heads#L93
Disable:
https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/blob/qrb5165-ubun1.0-14.1a/recipes-kernel/linux-msm/files/dts/m0104/m0104-modalai-qupv3.dtsi?ref_type=heads#L98

[이광철]

@admin

Do I need to change the kernel to use spi14 using the voxl_spi_init function?
or
Is this possible using voxl2_SDK_1.1.1?

Thanks

[Alex Kushleyev]

@이광철 yes, you have to to switch the kernel. you can try using the old kernel from sdk 1.1.1. You can test it before flashing permanently : https://docs.modalai.com/voxl2-kernel-build-guide/#test . I dont see any significant changes in 1.1.2 that may affect you, but you should test before overwriting your kernel

[이광철]

@Alex-Kushleyev

Hi.
I rebuilt the kernel referring to your advice.

The modified contents are as follows.
modify file: build_mount/lu.um.1.2.1/apps_proc/poky/meta-voxl2-bsp/recipes-kernel/linux-msm/files/dts/m0104/m0104-modalai-qupv3.dtsi

/* M0104 - J10 - GPIO 40-44 */
&qupv3_se14_spi {
status = "ok";
};

/* M0104 - J10 JST connector */
&qupv3_se14_2uart {
status = "ok";
};

./qrb5165-clean.sh
./qrb5165-build.sh -m M0104

After building the kernel, ttyMSM0 was created in /dev.
However, spidev14.0 is still not found.

ls /dev/spidev*
spidev0.0 spidev3.0

I'm looking forward to your advice.
Thanks.

[Alex Kushleyev]

@이광철 , you need to disable uart:

/* M0104 - J10 JST connector */
&qupv3_se14_2uart {
status = "disabled";
};

[이광철]

@Alex-Kushleyev

First of all thank you for your advice.
build_mount/lu.um.1.2.1/apps_proc/poky/meta-voxl2-bsp/recipes-kernel/linux-msm/files/dts/m0104/m0104-modalai-qupv3.dtsi

/* M0104 - J10 - GPIO 40-44 */
&qupv3_se14_spi {
status = "ok";
};

/* M0104 - J10 JST connector */
&qupv3_se14_2uart {
status = "disabled";
};

Modified as above.

After building the kernel, the contents of /dev are as follows.
Why doesn't spidev14.0 exist?
What am I doing wrong?

voxl2-mini:/dev$ ls spidev*
spidev0.0 spidev3.0

voxl2-mini:/dev$ ls tty*
tty tty10 tty13 tty16 tty19 tty21 tty24 tty27 tty3 tty32 tty35 tty38 tty40 tty43 tty46 tty49 tty51 tty54 tty57 tty6 tty62 tty8 ttyprintk
tty0 tty11 tty14 tty17 tty2 tty22 tty25 tty28 tty30 tty33 tty36 tty39 tty41 tty44 tty47 tty5 tty52 tty55 tty58 tty60 tty63 tty9
tty1 tty12 tty15 tty18 tty20 tty23 tty26 tty29 tty31 tty34 tty37 tty4 tty42 tty45 tty48 tty50 tty53 tty56 tty59 tty61 tty7 ttyMSM0

[Alex Kushleyev]

@이광철 , just to double check.. after building the kernel, did you install it to voxl2 mini?

If all else fails, you can test (without overwriting) the kernel from SDK 1.1.1 like this :

voxl2-mini_SDK_1.1.1/system-image$ adb reboot bootloader
voxl2-mini_SDK_1.1.1/system-image$ fastboot boot qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot.img' (17552 KB)                      OKAY [  0.509s]
Booting                                            OKAY [  0.033s]
Finished. Total time: 0.553s

then adb into the device and check spi port in /dev/

[이광철]

@Alex-Kushleyev

just to double check.. after building the kernel, did you install it to voxl2 mini?
Yes
I built the kernel and installed it on voxl2-mini.
The process is as follows.
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb reboot bootloader
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot flash boot_a qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot_a' (20088 KB) OKAY [ 0.458s]
Writing 'boot_a' OKAY [ 0.026s]
Finished. Total time: 0.637s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot flash boot_b qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot_b' (20088 KB) OKAY [ 0.463s]
Writing 'boot_b' OKAY [ 0.032s]
Finished. Total time: 0.654s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot reboot
Rebooting OKAY [ 0.001s]
Finished. Total time: 0.006s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb wait-for-device
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb shell
▂▂▂▂▂▂▂▂▂▂▂▂▂
▂▄▆▆██▛▀▀▀▀▀▀▀▀▜████▆▆▄▂
███╗ ███╗ ██████╗ ██████╗ █████╗ ██╗ ▗▆████▀▔ ▔▔▀▀▀▀▚▄
████╗ ████║██╔═══██╗██╔══██╗██╔══██╗██║ ▗▟████▀ ▗██▖ ▐█ ▝▀▆▄▄▄
██╔████╔██║██║ ██║██║ ██║███████║██║ ▟████▀ ▗█▘▝█▖ ▐█ ▜█▀█▄
██║╚██╔╝██║██║ ██║██║ ██║██╔══██║██║ █▌ ▐█▌ ▗█▘ ▝█▖ ▐█ ▐▄ ▄█
██║ ╚═╝ ██║╚██████╔╝██████╔╝██║ ██║███████╗ ▀████ ▗█▘ ▝█▖ ▐█ ▂▄███▀
╚═╝ ╚═╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝╚══════╝ ▀▀██▄▄ ▂▆███▀
▀▀██▄▄ ▀▀▆▄▄▄▄▆██▀▀▀▘

---

system-image: 1.7.1-M0104-14.1a-perf-nightly-20231025
kernel: #1 SMP PREEMPT Wed Mar 27 02:44:30 UTC 2024 4.19.125

hw version: M0104

voxl-suite: 1.1.2

no current network connection

[이광철]

@Alex-Kushleyev

I downloaded voxl2-mini_SDK_1.1.1.tar.gz from https://developer.modalai.com/asset/eula-download/141

It was tested as follows.
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb reboot bootloader
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot boot qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot.img' (17548 KB) OKAY [ 0.382s]
Booting OKAY [ 0.034s]
Finished. Total time: 0.471s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb shell

                                                     ▂▂▂▂▂▂▂▂▂▂▂▂▂
                                                ▂▄▆▆██▛▀▀▀▀▀▀▀▀▜████▆▆▄▂

███╗ ███╗ ██████╗ ██████╗ █████╗ ██╗ ▗▆████▀▔ ▔▔▀▀▀▀▚▄
████╗ ████║██╔═══██╗██╔══██╗██╔══██╗██║ ▗▟████▀ ▗██▖ ▐█ ▝▀▆▄▄▄
██╔████╔██║██║ ██║██║ ██║███████║██║ ▟████▀ ▗█▘▝█▖ ▐█ ▜█▀█▄
██║╚██╔╝██║██║ ██║██║ ██║██╔══██║██║ █▌ ▐█▌ ▗█▘ ▝█▖ ▐█ ▐▄ ▄█
██║ ╚═╝ ██║╚██████╔╝██████╔╝██║ ██║███████╗ ▀████ ▗█▘ ▝█▖ ▐█ ▂▄███▀
╚═╝ ╚═╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝╚══════╝ ▀▀██▄▄ ▂▆███▀
▀▀██▄▄ ▀▀▆▄▄▄▄▆██▀▀▀▘

---

system-image: 1.7.1-M0104-14.1a-perf-nightly-20231025
kernel: #1 SMP PREEMPT Thu Oct 26 04:23:26 UTC 2023 4.19.125

hw version: M0104

voxl-suite: 1.1.2

no current network connection

spidev14.0 still does not exist.
There is something strange.
Why voxl-suite: 1.1.2?
voxl-suite: 1.1.1 Isn't that correct?

[Alex Kushleyev]

@이광철 , if you update just the kernel (or boot using a temporary one), the rest of the file system is unaffected, so voxl suite will remain the same. You can look at the kernel build dates to see the difference (it is also printed when you start adb shell).

I am not sure why spi is not showing up, will need to ask @admin

[Alex Kushleyev]

Maybe the change spi ->uart was actually made before sdk 1.1.1. We will need to double check that.

[Alex Kushleyev]

I confirmed that kernel from SDK 1.1.1 does not have the spi mapped. So i tried the kernel from SDK 1.0.0 and it does. In this case my board has SDK 1.1.1 installed, but i am booting into kernel from SDK 1.0.0.

voxl2/builds/voxl2-mini_SDK_1.0.0/system-image$ adb reboot bootloader
voxl2/builds/voxl2-mini_SDK_1.0.0/system-image$ fastboot boot qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot.img' (17552 KB)                      OKAY [  0.508s]
Booting                                            OKAY [  0.034s]
Finished. Total time: 0.573s

...
adb shell

system-image: 1.7.1-M0104-14.1a-perf-nightly-20231025
kernel:       #1 SMP PREEMPT Fri May 19 22:53:15 UTC 2023 4.19.125
--------------------------------------------------------------------------------
hw version:   M0104
--------------------------------------------------------------------------------
voxl-suite:   1.1.1
--------------------------------------------------------------------------------
no current network connection
--------------------------------------------------------------------------------


voxl2-mini:/$ ls /dev/spidev*
/dev/spidev0.0  /dev/spidev11.0  /dev/spidev14.0  /dev/spidev3.0

Now, i am not sure why your manual kernel build did not work. if you still cannot get it to work, let us know, we can build it with spi enabled and test it for you.

[이광철]

@Alex-Kushleyev

I downloaded voxl2-mini_SDK_1.0.0.tar.gz from https://developer.modalai.com/asset/eula-download/127

It was tested as follows.

C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb reboot bootloader
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot flash boot_a qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot_a' (17552 KB) OKAY [ 0.399s]
Writing 'boot_a' OKAY [ 0.023s]
Finished. Total time: 0.565s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot flash boot_b qti-ubuntu-robotics-image-m0104-boot.img
Sending 'boot_b' (17552 KB) OKAY [ 0.397s]
Writing 'boot_b' OKAY [ 0.019s]
Finished. Total time: 0.561s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>fastboot reboot
Rebooting OKAY [ 0.000s]
Finished. Total time: 0.005s
C:\Users\User\Desktop\OpenSDP\platform-tools_r33.0.3-windows\platform-tools>adb shell

system-image: 1.7.1-M0104-14.1a-perf-nightly-20231025
kernel: #1 SMP PREEMPT Fri May 19 22:53:15 UTC 2023 4.19.125

hw version: M0104

voxl-suite: 1.1.2

no current network connection

voxl2-mini:/dev$ ls spi*
spidev0.0 spidev11.0 spidev14.0 spidev3.0

OK!
The spidev14.0 file exists.

I tested it as below:
voxl2-mini:/dev$ qrb5165io-spi-test -d 0
failed to ping icm42688p IMU

voxl2-mini:/dev$ qrb5165io-spi-test -d 11
failed to ping icm42688p IMU

voxl2-mini:/dev$ qrb5165io-spi-test -d 3
[INFO] success! ICM42688 Detected

voxl2-mini:/dev$ qrb5165io-spi-test -d 14

There is no response to the qrb5165io-spi-test -d 14 command.
is this right?
Is spidev14.0 not working?

[Alex Kushleyev]

@이광철 , do you have anything connected to spidev14.0 ? You need a device connected to the spi port.

If you look at the source code for this test app, it simply tries to ping a specific IMU device, which happens to be installed on board on SPI3 (ICM42688 IMU) : https://gitlab.com/voxl-public/voxl-sdk/core-libs/libqrb5165-io/-/blob/master/apps/examples/qrb5165io-spi-test.c

So, you should connect your desired device to J10 and modify the example to communicate with your device.

Also, based on this documentation, https://docs.modalai.com/voxl2-mini-connectors/#j10-pin-out-spi-mode-gpio_67--low-kernel-rebuild-required-to-use, you need to set the GPIO before using:

voxl-gpio -w 67 1

I hope that helps

[Alex Kushleyev]

Another quick tip for testing SPI stuff. I found this useful:

spidev-test/spidev_test.c at master · rm-hull/spidev-test

Contribute to rm-hull/spidev-test development by creating an account on GitHub.

GitHub (github.com)

You can download this file to VOXL2, build it using

gcc -O2 spidev_test.c -o spidev_test

and then you can actually query the IMU on spi 3:

voxl2-mini:~$ ./spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
RX | 00 00 00 47 ...

and from here we know that 0x47 is actually the value WHOAMI register of ICM42688 IMU

The data i am sending to the device is 4 bytes used to query the imu, as done here . the value 0xF5 = 0x75 | 0x80 which tells the IMU to send back the value of register 0x75

[이광철]

@Alex-Kushleyev

I will connect my spi device and let you know the results after testing.
Thanks for your help.

[이광철]

@Alex-Kushleyev

Hi.

I tested it by connecting my spi device to j10.
This spi device is working normally in voxl2.
My program for testing also operates normally with this spi device in voxl2.
However, when I test the spi device and test program on voxl mini, there is no response to the voxl_spi_write function.

Also, the test below is the same as before.
voxl2-mini:/dev$ qrb5165io-spi-test -d 14
There is no response to the qrb5165io-spi-test -d 14 command.

I need your help and thanks in advance.

[이광철]

@Alex-Kushleyev

I tested according to your advice.
This is the result of testing on my mini.

voxl2-mini:~$ cd /usr/bin
voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
can't send spi message: Invalid argument
Aborted

[이광철]

@이광철

Alex-Kushleyev sorry.

voxl2-mini:~$ cd /usr/bin
voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
can't send spi message: Invalid argument
Aborted

This test was my mistake.

Below are the final test results.
voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
RX | 00 00 00 47 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ | ...G

[Alex Kushleyev]

@이광철 ,

Please note that qrb5165io-spi-test -d 14 is a test app that just tries to detect a specific IMU on the SPI port. If the specific IMU is not connected, the test will not be successful.

Are you able to read any data from your SPI sensor (using spidev_test -D /dev/spidev14.0 ... ? Can you share what your sensor is? You should look in the documentation of your sensor and it will tell you how to communicate with it. SPI protocol for reading / writing is specific to the device.

Also, don't forget about the gpio setting that needs to be made before using SPI 14 (voxl-gpio -w 67 1). this needs to be run after each reboot.

Alex