Questions tagged [device-tree]
The device-tree tag has no usage guidance.
2
votes
1answer
24 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
24 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
67 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
votes
0answers
23 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
votes
2answers
240 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 ...
3
votes
2answers
1k 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 \ ...
0
votes
0answers
171 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
...
1
vote
1answer
140 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
2k 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
147 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
votes
0answers
97 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
126 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 ...
0
votes
0answers
74 views
DTS Overlays Makefile
I'm going to add a new entry in the Makefile.
The suggested syntax for that entry is
dtbo-$(RPI_DT_OVERLAYS) +=
.
Looking at the list already loaded in Makefile I see a different syntax:
dtbo-$(...
1
vote
0answers
74 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
272 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 ...
1
vote
0answers
79 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 ...
1
vote
1answer
861 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 ...
0
votes
0answers
310 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
1k 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
48 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
318 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
3k 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
572 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
1k 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 ...
0
votes
1answer
411 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
2k 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 ...
3
votes
1answer
2k 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
796 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
4k 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 ...
0
votes
1answer
796 views
How to detect a device tree overlay at run time?
What is the best way to check at run time if a device tree overlay is loaded?
I've found info about checking individual GPIO pin status, and info about how to load the overlay (via config.txt), but I'...
0
votes
2answers
4k views
how to enable spi1? / pi 3 and two rc522 RFID readers
Is it possible to connect two RC522 readers with one RaspberryPi 3?
As far as I know I should just choose different CS pins for them (Add more than 2 SPI slaves).
I have following connections:
1st ...
1
vote
2answers
403 views
Raspberry pi HAT device-tree
I'm currently developping a Raspberry pi HAT. The Raspberry pi HAT must contain a EEPROM with several information in it. This information will be read at boot time in order to configure the Raspberry ...
0
votes
1answer
268 views
device tree and spi controller file
why is the file spi_bcm2708.c is not present inside the path linux/drivers/spi and while inside the boot partition of pi the bcm2708-rpi-version.dts file is only present.how come kernal use the ...
2
votes
1answer
771 views
i2c on a rpi-basic-image created with yocto
I'm attempting to get the i2c bus to work from a raspberry pi image created from yocto. I have looked at other peoples solutions but they are all o do with raspbian or some other flavour of os.
My /...
-1
votes
0answers
132 views
Restoring Wi-Fi while keeping device tree disabled
Although it's advised to keep it enabled, it was the only way for me to get an NFC board working but just like this forum thread states, disabling the device tree makes the wlan interface disappear.
...
1
vote
1answer
1k views
unable to install 1-wire temperature sensor
I am trying to figure out why I cannot get temperature sensors working connected to my RPi2. I have followed almost every possible guide on the internets without luck and the answers* provided here ...
5
votes
5answers
4k views
DS18B20 w1-gpio Device Tree gpiopin NOT = 4
I have a HAT which blocks GPIO4 so I cannot use the default pin for the temperature sensor, but I just cannot get it to work on another pin!
I just get lots of 00- instead of 28- in /sys/bus/w1/...
1
vote
0answers
377 views
Setup gpio 23 as shutdown & startup
Followed this tutorial & have included my device tree config below. I've configured my pull up resistor for my button to function properly once my app is running, but I'm curious; is there a way ...
2
votes
1answer
4k views
How to use i2c_gpio with Raspberry Pi?
I would like to use the i2c_gpio software i2c kernel module because the broadcom hardware i2c does not support I2C_M_NOSTART. How do I do this?
I think that in order to do it I need to take the ...
