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Do you have an old pair of PC speakers, or an old Hi-Fi, that you would like to convert into a pair of Bluetooth® speakers to play music from your phone? A Raspberry Pi can be easily used as an audio bridge between a Bluetooth® device and an analog speaker system, to make this possible. In this quick guide, I will show you how to set up the software on a Pi, using PipeWire, to achieve this. In my

Over the past 18 months, we have been on a roller-coaster ride developing futex2, a new set of system calls. As part of this prolonged effort, the futex_waitv() syscall has now successfully landed in Linux 5.16. A followup of the initial futex syscall, this new interface aims to overcome long term issues that have been limiting the way applications use the Linux kernel. But what exactly is futex?

After six months of reverse-engineering, the new Arm “Valhall” GPUs (Mali-G57, Mali-G78) are getting free and open source Panfrost drivers. With a new compiler, driver patches, and some kernel hacking, these new GPUs are almost ready for upstream. In 2021, there were no Valhall devices running mainline Linux. While a lack of devices poses an obvious obstacle to device driver development, there is

Modern USB gadget on Linux & how to integrate it with systemd (Part 1) tl;dr: Automate your gadget creation. A look at how to implement USB gadget devices on Linux machines which have the necessary UDC hardware, automate the manual configfs process via declarative gadget "schemes", and use systemd for gadget composition at boot time. The big picture In order to understand what is a USB gadget we n

Linux 5.2 was released over one year ago and with it, a new feature was added to support optimized case-insensitive file name lookups in the Ext4 filesystem - the first of native Linux filesystems to do it. Now, one year after this quite controversial feature was made available, Collabora and others keep building on top of it to make it more and more useful for system developers and end users. The

In the early days of VR on Linux, when plugging in an HMD into a system completely unaware of what it was, the display was initialized as generic desktop display and the window manager extended the desktop to it. This was obviously undesirable, but you were still able to see cropped and perspectively incorrect desktop windows on your HMD. Only the bravest of us were keen enough to find the cursor

Interested in learning more about low-level specifics of the eBPF stack? Read on as we take a deep dive, from its VM mechanisms and tools, to running traces on remote, resource-constrained embedded devices. Note: These blog posts will be focusing on eBPF so for our purpuses BPF and eBPF are the same thing and can be used interchangeably. The name/acronym deasn't mean much anymore because the proje

In the beginning, Android did not really have a graphics stack. It was just pushing frames directly to framebuffers and hoping for the best, the approach worked for quite some time. However, over time, the usecases became more and more complex and a new graphics stack was necessary. About 6 years ago the Android team conducted a lot of research and quickly realized that the mainline kernel was far

For the last month or so, I've been playing with a new project during my work at Collabora, and as I've already briefly talked about at XDC 2018, it's about time to talk about it to a wider audience. What is Zink? Zink is an OpenGL implementation on top of Vulkan. Or to be a bit more specific, Zink is a Mesa Gallium driver that leverages the existing OpenGL implementation in Mesa to provide hardwa

Dynamic profilers are tools to collect data statistics about applications while they are running, with minimal intrusion on the application being observed. The kind of data that can be collected by profilers varies deeply, depending on the requirements of the user. For instance, one may be interested in the amount of memory used by a specific application, or maybe the number of cycles the program