Questions tagged [device-tree]
a Device Tree (DT) is a description of the hardware in a system
59
questions
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19 views
DTS for custom board with sc16is752
im trying to write DTS for my custom board, but still is smth wrong:
My hardware description on SPI0:
CS-gpios:
8 7 25 16 23
CS0 - SC16IS752 (IRQ 24)
CS1 - MCP2515
CS2 - RFID RC522 module
CS3 - RFID ...
2
votes
2answers
110 views
Re-configure SPI-CS as gpio while using SPI
I am on a raspberry pi 4. Using both SPI's with no need for either chip select. I'm running out of I/O and could really use those. Does anyone know if there is a way to repurpose the SPI chip selects ...
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0answers
35 views
Device Tree for Generic Output
I'm currently developing my first Pi Hat for a personal project. I've been exploring Device Trees and I'm quite liking the concept from the perspective that the userland code can address specific ...
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2answers
21 views
Location of .dtbs files - specifically uart0.dts and minimart-bt.dts
Does anyone know where I can find the precompiled .dtbs files - specifically uart0.dts and minimart-bt.dts?
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0answers
23 views
yocto build for HAT seeed voicecard hardware
I own a 4-Mic HAT ReSpeaker that I would like to install it on raspberrypi. The raspberrypi image is built using yocto, I can able to build the kernel module and dtbo, but dont know how to install it ...
1
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2answers
98 views
How can RpiZW interface three SPI ADS1248 ADC, one microSD adapter, and one Ethernet Adapter?
I'd like to connect multiple different SPI devices to a Raspberry Pi Zero W (at least 5), with a few specific requirements. The devices would be, if possible:
1x ENC28J60 Ethernet SPI adapter - this ...
0
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0answers
85 views
DS18B20 does not have a unique adress in /sys/bus/w1/devices
The problem:
I am trying to use a RW1820 (DS18B20), to display the temperature.
yet it does not show up in devices. Only w1_bus_master 1 appears.
Setup:
Raspberry Pi 4
1-Wire Temperature Sensor ...
0
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0answers
60 views
LAN_RUN device tree dt-blob.dts for LAN95XX
I have setup Compute Module 3+ with LAN9512 for ethernet port.
The only problem is the ethernet chip needs a pull_up for shutdown
I have connected GPIO31 to LAN_RESET in my circuit
I am trying to ...
0
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1answer
693 views
Device Tree configuration for I2S sound (MAX98357A)?
What needs to be done to run an I2S DAC/Amplifier board based on MAX98357A (datasheet) that appears to be a clone of this well-documented Adafruit product with the corresponding Device Tree overlay?
...
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48 views
Raspberry Pi 3 : how to find device number and card number with bluetooth
I'm trying to set up google assistant on my raspberry pi with this guide:
https://pimylifeup.com/raspberry-pi-google-assistant/comment-page-2/?unapproved=27549&moderation-hash=...
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0answers
29 views
Problem in initiating i2c driver module for bmp180 i2c based sensor at kernel level
For leaning purpose i am writing a i2c client kernel module for bmp180 pressure sensor.
My kernel code is ->
#include <linux/version.h>
#include <linux/module.h>
#include <linux/init....
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0answers
28 views
Need help with Compute Module 3 PCB development
I am designing a Compute Module 3 based PCB online on : Gumstix
I can download the CAD files and it automatically generates the device tree so it seemed convenient. I created a custom design and ...
1
vote
1answer
608 views
Error when connecting more than ten USB devices on Raspberry Pi 4 [duplicate]
What is the limit of USB devices in raspberry pi4?
We have an external USB hub with its power supply and 10 devices fall off with errors.
[Wed Mar 11 09:04:43 2020] usb 1-1.3.4-port1: Cannot enable. ...
0
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1answer
739 views
Re configuring GPIO pins for SPI protocol
GPIO pins 19,21,23,24,26,35,38,40 are dedicated for SPI protocol. Is it possible to use other GPIO pins for SPI? If yes, how do we do it?
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0answers
272 views
Applying dwc2.dtbo to bcm2711-rpi-4-b.dtb at build time triggering FDT_ERR_NOTFOUND
I'm trying to build a NixOS image for my Raspberry Pi 4b with the dwc2 device tree overlay applied.
Per advice from the #nixos-aarch64 IRC channel, doing this the Nix Way calls for configuring ...
0
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1answer
109 views
Trouble adding a gpio device to the device tree
I'm trying to connect an hx711 to GPIO23 and GPIO24 pins on an RPI3 A+, and I need to specify this in the device tree to have the hx711.ko driver be probed. I've been stuck on this problem for some ...
2
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1answer
54 views
Why DMA uses bus address rather than physical address?
Why DMA uses bus address rather than physical address?
And do we provide bus address or physical address in the device tree?
Where do we get to know these addresses that needs to be provided to the ...
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0answers
470 views
Creating a Device Tree Overlay for i2c device
I'm trying to create a Device Tree overlay for a i2c touch screen.
Things are a bit strange as the screen is a 16bit DPI so all usual i2c pins are consumed. I'm using a i2c-tiny-usb adapter to get an ...
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0answers
36 views
I2C client driver instantiation using Device Tree - probe did not get called
I am writing a sample and simple i2c driver in which I am trying to instantiate the
i2c client device using device tree overlay. I have got some DTE overlay sample which i have complied to .dtbo and ...
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0answers
197 views
Simple Sound Card with I2S - how do I switch frequencies?
I asked this a month ago, but didn't get an answer and so the thread was auto-deleted. It is becoming critical that this be solved, so I am reposting.
I have the simple sound card working with a ...
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0answers
86 views
Using waveshare LCD and SPI1 for LEDs
My problem is that I cant get SPI1 and the LCD screen to work at the same time.
Only SPI1 with the spi1-1cs overlay worked and only the waveshare35a overlay working, I tried to make my own overlay ...
1
vote
1answer
224 views
Can I run 2 device tree overlay at the same time?
I'm trying to monitor some 4-20mA current loops and 0-10V generators with a RPi 3. I found these modules which would do the job:
https://widgetlords.com/products/pi-spi-2a0-raspberry-pi-analog-output-...
2
votes
1answer
144 views
Building an old kernel is not possible because the arch/arm/boot/dts/overlays/ directory does not exist
I've been trying to build a kernel from the 4.14.85 version. I followed the instructions from the official documentation but instead of using the latest version you can find in the repository I ...
1
vote
1answer
781 views
Use internal pull up resistors with the gpio-keys module in the device-tree
I have an external board with some buttons that are attached to gpio 20 and 21 which connects these pins to ground when pressed:
simulate this circuit – Schematic created using CircuitLab
I'd ...
3
votes
1answer
1k views
How do I add an i2c device to the device tree?
I am trying to add an mpu 9250 to the device tree of my RPi 3 A+ so that my custom driver's probe function will be called. I have followed this documentation about the Raspberry Pi device tree and ...
0
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0answers
50 views
What could trigger the removal of the WiFi device?
I discovered this morning that wlan0 on my RPi vanished during the night (at 04:14:13 in the unaltered log below):
Dec 18 03:38:46 rpi1 wpa_supplicant[407]: wlan0: WPA: Group rekeying completed with ...
0
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2answers
1k views
gpio-shutdown doesn't seem to have an effect
We are trying to have the Pi shut down gracefully when power is removed. We have a battery connected so that it will have time to shut down. So far, our attempts to use gpio-shutdown have been ...
7
votes
4answers
7k views
Emulate Raspberry Pi zero W with Qemu failed due to missing dtb
I am trying to emulate a Raspberry Pi zero W with Qemu based on an image I used on a real Raspberry Pi zero W.
The command I am using is:
sudo qemu-system-arm \ ...
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0answers
432 views
Connecting RAW NAND through GPIO
I'm trying to define a device tree for connecting an external raw NAND using GPIO on RPI3.
I found that there are available drivers, and I found an example in the sources' "Documentation" directory
...
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1answer
505 views
How and from where is the ENC28J60 driver loaded?
I have a raspberry CM3 setup where I added an external eNet port so that I have internet connectivity. It is very similar to the break-out board setup such as this one which is also based on the ...
1
vote
2answers
5k views
Rpi3 is the hardware watchdog enabled by default
I have RaspberryPI's 3 (running both Jessie and Stretch) and tested on both
In order to enable the watchdog timer, In many posts I saw that add in the /boot/config.txt a line with:
dtparam=watchdog=...
2
votes
1answer
474 views
Change Device Tree to pullup pin at boot
I trie to add a LTC2954 to the raspberry pi zero w. I designed and produced a prototype pcb with an lipo management system for load and loadsharing. My problem is, that the KILL Pin of the LTC2954 has ...
0
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0answers
181 views
Difference between sound and audio nodes in RPi 3 device tree?
I looked a bit into the device tree of Raspbian 9 on Raspberry Pi 3, using:
dtc -I fs /proc/device-tree > myrpi-dev-tree.txt 2>&1
I've noticed there is a node called audio:
audio {
...
2
votes
0answers
218 views
Raspberry Pi remap DPI pins [closed]
I'm trying to hook up my Raspberry Pi a to custom display hat via the parallel display interface (GPIO Pins, not ribbon cable). The problem I'm facing is that the DPI pins are rather awkwardly placed ...
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0answers
148 views
Access more than two (2) slaves on spi0
Supposedly, there is a new driver that supports arbitrary GPIOs for SPI0 channel select, that is configurable via the device tree.
Everything I try only half works. The hard works. If I toggle the ...
2
votes
0answers
416 views
Accessing 3+ SD/MMC /dev/mmcblk devices
I've successfully followed some instructions for access 2 SD cards via SPI on a Raspberry Pi 3: https://ralimtek.com/Raspberry_Pi_Secondary_SD_Card/
How do I configure it to access more than 2 SD ...
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vote
0answers
138 views
In simultaneous use of SPI0 and DPI Mode 3 interfaces, can SPI0 CS0 be moved to a pin other than 8?
I am attempting to design a device using a Pi Zero which needs to connect to both an ENC18J60 SPI ethernet controller, and a VGA monitor via Mode 3 DPI and the Mincepi Pi Zero pi2vga schematic. While ...
3
votes
2answers
2k views
dtoverlay=gpio-poweroff not working on raspberry pi 3 B
Problem:
I have a Raspi 3B rev: a02082 (Q1 2016 3 Model B 1.2 1 GB (Mfg by Sony)) running raspbian jessie kernel 4.9.35-v7
I want to signal to a power management circuit that filesystems ...
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0answers
605 views
SPI doesn't work because of device tree
I have the same problem as this person:
SPI enabled in device tree, but I can't use it
I tried commenting in the original thread but the community rules don't allow me to comment because I don't ...
1
vote
1answer
3k views
How do i use DeviceTree to init GPIO to a set value?
Hello i've got a board connected to my raspberry pi 3 and according to the pin set on boot of the raspberry this shield reboot which is problematic. I need to be able to reset the board and control ...
3
votes
1answer
62 views
DeviceTree magic strings
I recently stumbled over the MagPi Essentials Camera. In chapter 7 "Flash photography using an LED" (p.41+), they show how to configure pin BCM17 to act as a flash for the official Raspberry Pi Camera....
2
votes
0answers
516 views
device tree and led blink
I am trying to create one led driver via device tree in Rpi 3
I had created the dtsi file
/dts-v1/;
/plugin/;
/ {
compatible = "brcm,bcm2837";
fragment@0 {
target = <&...
4
votes
1answer
5k views
SPI enabled in device tree, but I can't use it
I am trying to use SPI interface on Raspberry Pi 1 B (OS: Raspbian July 2017, kerenl 4.9.5). To do this, I am using wiringPi. I confirmed that wiringPi works via gpio readall
To load SPI:
gpio load ...
0
votes
2answers
1k views
How to use advanced GPIO functions via sysfs?
The GPIO ports can be accessed using sysfs interface located in /sys/class/gpio. However, I failed to found more detailed documentation, most of which only describes plain read/write operation.
What ...
3
votes
1answer
4k views
How to build my very own device tree (and if I need to)
Let me preface this by saying I don't know much about device trees. I do know a bit about ATAGs, since I'm working with this operating system that currently only uses ATAGs.
I'm modifying the ...
1
vote
1answer
568 views
apds 9960 on raspberry pi zero
I would like to use the apds9960 (light/gesture sensor) on rp0 - utilizing the kernel iio driver, which is already available, but there is no dt overlay yet. I guess I need to:
write the dts file
...
0
votes
1answer
3k views
Compile a dts file (dt overlay)
Hello folks maybe I have misunderstood something but I am not sure how to compile my dt overlay file with the etc command (!) I already know that I have to use the @ parameter .
The effect of ...
2
votes
1answer
3k views
How to use BMP280 SPI Kernel Module
I got a adafruit BME280 sensor board and I wired it to the raspberry pi zero via spi. According to the datasheet I can read sensor data from the device via the userspace spi interface. Everything ...
0
votes
1answer
2k views
Disable pull-up resistor on pps-gpio pin
I am using the pps-gpio dtoverlay. My /boot/config.txt has these lines:
# Expect the GPS 1PPS pin to be connected to GPIO3
dtoverlay=pps-gpio,gpiopin=3
Problem is, that the GPS Module (SkyTraq Venus)...
2
votes
1answer
6k views
Missing configuration options on raspi-config screen??? No SPI or Device Tree
Downloaded NOOBS onto my SD card and got my RPi3 up and running.
I'm trying to enable Device Tree and SPI via the advanced options bit on the raspi-config blue screen (so i can install my 3.5inch ...
