> I also thought I’d message the vendor and ask them if they could share any specifications or docs regarding their protocol. To my surprise, Nanoleaf tech support responded to me within 4 hours, with a full description of the protocol that’s used both by the Desk Dock as well as their RGB strips.
How cool is that? Too many vendors still think that they have valuable intellectual property in such relative trivialities. And that handing out the specs freely helps their competitors more than themselves.
I almost had that experience with one of the popular PC liquid cooling hardware vendors around 10 years ago.
I emailed them saying I'd be interested in developing drivers for their hardware for Linux as I was a happy customer and was immediately put in touch with one of the managers and their engineering team.
Made quite a bit of progress before the whole thing was shut down because one of their component vendors threatened them saying it'd be a breach of their contract with them.
Apparently that vendor sold a "datacenter" (non consumer) version of that hardware for which they charged a hefty license fee for the management software (which was Linux compatible).
Jokes on them, someone reverse engineered the whole thing with a USB analyzer years later and published it XD. (not me)
Yeah that part of the article put a big smile on my face.
I did the same thing back in college, when I was in a lab. We wanted to do some research on Wi-Fi signals, and I happened to own a bunch of Wi-Fi adaptors produced by SomeSmallTech Co. Ltd., which featured relatively new Atheros chips and didn't have Linux drivers at the time.
So I sent an email to the company's public email address, asking for some datasheets, "for science". To my disappointment, presumably a PR person replied that they "don't have a company policy to collaborate with academic research". (But they did send a quick reply, kudos to that.)
Funnily enough, years later I ended up working for said company. Naturally, when I first logged into the company network, I searched for the datasheets I asked for. There were "classified" watermarks all over the PDFs :)
It's not the IP, it's sadly how people react. Some folks will be appreciative of help, credit to them. Others will immediately get back how they tried it, it didn't work and now they need you to rewrite everything, or do their project for them, or redesign your product to match what they want it to be. And if you politely refuse, it quickly escalates to threats of trashing your business through every channel, and other things.
So, the safest thing to do is not give details at all, or "leak" them like another reply in this thread mentions.
This has to put them in the top 0.01% of companies that make consumer electronics.
I can think of only a few companies that bother to publish any details... And most of them are focused on industrial customers where it isn't unreasonable to need certain protocol details for integration or even just compliance with certain regulatory systems.
Maybe things are changing?
I have noticed that some of the LED light controllers you see on AliExpress are leaning in to open firmware standards. 5 years ago, you bought the controller and had to flash your own firmware. Now, there's an option at checkout to select an open source firmware. Some even have a USB port built in for flashing!
I wish more vendors would put "Linux support" on the package. Or maybe "Unofficially supported in Linux" or "Linux community support" if they don't want to get their fingers burned.
Maybe this kind of thing should be enforced in the GPL (as many devices use Linux under the hood).
IME, Linux support is often mentioned on the package these days. But you still need to look it up anyway because it's often a vendor source dump for a particular kernel version. Such drivers are often not that good. Notable exception: my Brother printer-scanner-copier has been working fine with its vendor-provided user space driver for ~10 years now. I think it has not been updated for most of that time. It contains 32 bit binaries!
I have a solar inveter from a company, aparticular German brand. I wanted to use home assistant with it so I needed rs232 data.. tried the support and they asked me to sign an NDA.
Okay, cool. I did with a fake name, address and everything and they sent a file..
Turns out the file is available online.
Facepalm pro Max.
So my question is, what kind of "IP" is in a data sheet that needs protection ? And this isnt even some secret product but a generic solar product sold by millions.
They have asked to the legal team who basically don't know shit about what us do and who will always take the most conservative approach possible. So you'll get either: no answer, a "NO" answer or an "NDA" answer.
But it also makes me a little bit sad. The original parallel port and even ISA interface seemed so simple by comparison, with less layers of abstraction. Just run a wire, and write to a port.
I remember when I was a kid, I found a breakout board in an electronics store's random clearance parts bin, with an ISA header on an edge. On a whim I took it home and wire-wrapped a 7-segment LED onto it. Power and ground were easy. Each segment was hooked to a data line, through a simple buffer IC. I cheated and used only a minimal number of address lines to feed the enable port (guessing through a simple AND gate or something). I was amazed when I wrote to that address and it worked the first time!
I look at a protocol like USB, with hundreds of pages, and instead of that curious excitement and enablement I felt back then, I feel a bit overwhelmed.
USB is designed to solve a complex, but necessary problem.
1. Hot-plug.
2. High speeds with long cables of dubious quality.
3. Multiplexing multiple devices on a single wire with hubs.
4. Reliable transmission on lower layer, so higher level protocols don't need to worry about it.
5. Multiple speeds with negotiation.
6. Newer USB standards support multiple power voltages with negotiation.
All that said, old USB protocols like USB 1.1 is not that hard. You don't need those hundreds of pages, only a subset of them. There are some tutorials in the Internets which will help you to understand everything, from wire signalling to application interface. Don't use USB reference as a learning source. These days ChatGPT probably will guide you over every layer. Just stick with old standards, they are simpler and plenty of devices use them.
With enough persistence and some fast enough MCU you should be able to bit-bang USB 1.1 LS (1.5 Mbps) and write some simple USB device. That will require to implement all layers of USB and I'm pretty sure it's not impossible task.
> The original parallel port and even ISA interface seemed so simple by comparison, with less layers of abstraction. Just run a wire, and write to a port.
All those layers of abstraction is likely what allows us to hook up a single wire to our laptops and get multiple very fast ports from the docking station along with power and display output.
I sometimes think about this, starting from scratch with a computer hardware and software stack that disallowed all of the layers of abstraction that have built up over the decades.
Yeah many of the abstractions help with performance but maybe there's value giving up much of that performance in exchange for simplicity.
For toy tinkering, to replicate something like the old ability to just write a byte to an IO memory location and have it appear on the pins of a parallel port, you could design a simple USB peripheral that did similar. Give it a set of DIP switches to pick a number (4 for 0-f, more would probably be overkill but feel free) and have the driver present something like /proc/simpleio/device<num>/in and /proc/simpleio/device<num>/out/pin<num> for reading & writing¹. If you use the same set of pins for in and out, /proc/simpleio/device<num>/config to state which direction each is expected to work, and perhaps set voltage options (probably per device, per pin sounds overkill for this). Release the full design and let people make their own, sell pre-made boards and cases and/or let others do that (or just the boards and have people 3D-print their own cases). Devices could have as many pins as the maker likes.
That would only cover the real basics: reading/writing the hi/low status of pins. Other things people might want is analogue voltage control/read (for many sensors) or pulse control (for controlling servos and such). Things like that could be mapped into the /proc/simpleio/device<num>/{in|out}/pin<num> files. Perhaps for setting/reading multiple pins at a time perhaps have something like /proc/simpleio/device<num>/{in|out}/allpins. You could expand the feature in many ways, though TBH beyond the simple hi/low thing people are probably better off getting an rPi or microcontroller and using all the available devices and plans there are out there already for their IO pins and using something newer.
--------
[1] Not sure what you'd do for Windows, I'd be inclined to release a Linux driver and let the Windows community worry about one for their platform.
Serial ports still exist today. Even in desktop computers (though usually in weird underpowered ones designed for industrial applications and such). Even the most GAMING of motherboards have headers ready for one or even more serial ports to mess with. All you need is a cable and a card to slot into a PCIe bracket!
USB itself, at least the 1.1 protocol that's still used for some devices today, isn't all that complicated in itself: https://youtu.be/wdgULBpRoXk
Many if the complicated parts here, like device identifiers, are the things you'd need to manually configure if you were to use a serial port. Those hundreds of pages are similar to the hundreds of device types, vendors, and models that Windows would list when you clicked "add new hardware" back in Windows 98. When push comes to shove, you're just sending energy pulses down wires, there's just a chip in there that helps collect pulses so you don't need to manage the timing manually.
It’s a userspace USB HID driver in rust, which is honestly more interesting/applicable to me than a kernel driver, which is what I thought it meant from the title.
I really enjoyed the way this post was written, i.e. it includes the code, how it was run, the false paths, etc. You almost get to live through the author's journey and how he figured out just enough to get something working.
Upon reading the title I thought this was going to be about how easy it is to write or modify a Linux driver when using a LLM even if you know nothing about the subject.
No LLM needed. Kernel driver code for simple things is usually copy-paste-modify. Find something that works with an HID interrupt based device, and modify that. If you want a /sys led, copy from that. It's only if you try to push to mainline you need to worry about understanding it, but they'd probably smell LLM trash from miles away.
I enjoyed this post, but I'm eager to hear what the next step would be for a real "production" userspace driver. Are these typically just daemons that are configured to run at start up? And then some configuration GUI communicates with it over a socket or something?
You could certainly do that, and it would make a ton of sense if there's both no standard software API for communicating with that type of device, and it's important that multiple pieces of software that communicate with the device are able to run at the same time (or you want to avoid repeating work when starting software multiple times). ADB (Android Debug Bridge) takes this approach.
If there is an applicable standard software API (either multiplatform like a filesystem, or a special one exposed by the OS kernel [1] ), the driver probably belongs in the Linux kernel (or in the form of a Windows driver on that platform). My understanding is that GPU APIs are an exception on Linux, and are implemented in userspace by a piece of software called MESA. You could also use the daemon approach in this case if you don't want to bother with getting a driver added to the kernel.
For a more niche device where exclusive access is acceptable and every piece of software would need to add special support for this specific type of device anyway, it's a lot simpler to distribute the driver as a library that software authors can include in their program. If there are several devices that work similarly but communicate differently, you could have one library that either includes multiple drivers, or exposes a common interface that other libraries can implement.
A downside of any approach for USB devices on Linux that isn't a kernel driver is that one or more udev rules will need to be added (as the article described). This also applies when using a device that uses a supported USB protocol, but has different IDs than the ones listed in the kernel driver.
[1] More devices fall into this category than you might expect. For example, Linux has an API for communicating with CAN devices called SocketCAN, so if you're writing a driver for a CAN device that connects via USB and exposes the full CAN bus over USB (maybe something that goes in or connects to a car), you should write a kernel driver that converts data between SocketCAN and whatever USB protocol is being used (assuming one doesn't already exist, a lot of USB CAN devices use protocols that already have drivers in the kernel). SocketCAN only exposes the raw data extracted from the CAN frames, so if you want to expose an easy way to control a particular CAN device, that belongs in a userspace library that uses the SocketCAN API under the hood.
Typically production userspace drivers run as daemons (often systemd services) with udev rules to detect device connections, exposing control via D-Bus, sockets, or a custom API that GUI applications consume.
Readit News
How cool is that? Too many vendors still think that they have valuable intellectual property in such relative trivialities. And that handing out the specs freely helps their competitors more than themselves.
I emailed them saying I'd be interested in developing drivers for their hardware for Linux as I was a happy customer and was immediately put in touch with one of the managers and their engineering team.
Made quite a bit of progress before the whole thing was shut down because one of their component vendors threatened them saying it'd be a breach of their contract with them.
Apparently that vendor sold a "datacenter" (non consumer) version of that hardware for which they charged a hefty license fee for the management software (which was Linux compatible).
Jokes on them, someone reverse engineered the whole thing with a USB analyzer years later and published it XD. (not me)
I did the same thing back in college, when I was in a lab. We wanted to do some research on Wi-Fi signals, and I happened to own a bunch of Wi-Fi adaptors produced by SomeSmallTech Co. Ltd., which featured relatively new Atheros chips and didn't have Linux drivers at the time.
So I sent an email to the company's public email address, asking for some datasheets, "for science". To my disappointment, presumably a PR person replied that they "don't have a company policy to collaborate with academic research". (But they did send a quick reply, kudos to that.)
Funnily enough, years later I ended up working for said company. Naturally, when I first logged into the company network, I searched for the datasheets I asked for. There were "classified" watermarks all over the PDFs :)
Strangely they all have a tacit policy to build their products at least partly on the results of academic research.
So, the safest thing to do is not give details at all, or "leak" them like another reply in this thread mentions.
I can think of only a few companies that bother to publish any details... And most of them are focused on industrial customers where it isn't unreasonable to need certain protocol details for integration or even just compliance with certain regulatory systems.
Maybe things are changing?
I have noticed that some of the LED light controllers you see on AliExpress are leaning in to open firmware standards. 5 years ago, you bought the controller and had to flash your own firmware. Now, there's an option at checkout to select an open source firmware. Some even have a USB port built in for flashing!
Maybe this kind of thing should be enforced in the GPL (as many devices use Linux under the hood).
Okay, cool. I did with a fake name, address and everything and they sent a file..
Turns out the file is available online.
Facepalm pro Max.
So my question is, what kind of "IP" is in a data sheet that needs protection ? And this isnt even some secret product but a generic solar product sold by millions.
Rs-232 protocol ? Really ?
But it also makes me a little bit sad. The original parallel port and even ISA interface seemed so simple by comparison, with less layers of abstraction. Just run a wire, and write to a port.
I remember when I was a kid, I found a breakout board in an electronics store's random clearance parts bin, with an ISA header on an edge. On a whim I took it home and wire-wrapped a 7-segment LED onto it. Power and ground were easy. Each segment was hooked to a data line, through a simple buffer IC. I cheated and used only a minimal number of address lines to feed the enable port (guessing through a simple AND gate or something). I was amazed when I wrote to that address and it worked the first time!
I look at a protocol like USB, with hundreds of pages, and instead of that curious excitement and enablement I felt back then, I feel a bit overwhelmed.
1. Hot-plug.
2. High speeds with long cables of dubious quality.
3. Multiplexing multiple devices on a single wire with hubs.
4. Reliable transmission on lower layer, so higher level protocols don't need to worry about it.
5. Multiple speeds with negotiation.
6. Newer USB standards support multiple power voltages with negotiation.
All that said, old USB protocols like USB 1.1 is not that hard. You don't need those hundreds of pages, only a subset of them. There are some tutorials in the Internets which will help you to understand everything, from wire signalling to application interface. Don't use USB reference as a learning source. These days ChatGPT probably will guide you over every layer. Just stick with old standards, they are simpler and plenty of devices use them.
With enough persistence and some fast enough MCU you should be able to bit-bang USB 1.1 LS (1.5 Mbps) and write some simple USB device. That will require to implement all layers of USB and I'm pretty sure it's not impossible task.
All those layers of abstraction is likely what allows us to hook up a single wire to our laptops and get multiple very fast ports from the docking station along with power and display output.
You get some, you lose some.
Yeah many of the abstractions help with performance but maybe there's value giving up much of that performance in exchange for simplicity.
That would only cover the real basics: reading/writing the hi/low status of pins. Other things people might want is analogue voltage control/read (for many sensors) or pulse control (for controlling servos and such). Things like that could be mapped into the /proc/simpleio/device<num>/{in|out}/pin<num> files. Perhaps for setting/reading multiple pins at a time perhaps have something like /proc/simpleio/device<num>/{in|out}/allpins. You could expand the feature in many ways, though TBH beyond the simple hi/low thing people are probably better off getting an rPi or microcontroller and using all the available devices and plans there are out there already for their IO pins and using something newer.
--------
[1] Not sure what you'd do for Windows, I'd be inclined to release a Linux driver and let the Windows community worry about one for their platform.
USB itself, at least the 1.1 protocol that's still used for some devices today, isn't all that complicated in itself: https://youtu.be/wdgULBpRoXk
Many if the complicated parts here, like device identifiers, are the things you'd need to manually configure if you were to use a serial port. Those hundreds of pages are similar to the hundreds of device types, vendors, and models that Windows would list when you clicked "add new hardware" back in Windows 98. When push comes to shove, you're just sending energy pulses down wires, there's just a chip in there that helps collect pulses so you don't need to manage the timing manually.
Deleted Comment
If there is an applicable standard software API (either multiplatform like a filesystem, or a special one exposed by the OS kernel [1] ), the driver probably belongs in the Linux kernel (or in the form of a Windows driver on that platform). My understanding is that GPU APIs are an exception on Linux, and are implemented in userspace by a piece of software called MESA. You could also use the daemon approach in this case if you don't want to bother with getting a driver added to the kernel.
For a more niche device where exclusive access is acceptable and every piece of software would need to add special support for this specific type of device anyway, it's a lot simpler to distribute the driver as a library that software authors can include in their program. If there are several devices that work similarly but communicate differently, you could have one library that either includes multiple drivers, or exposes a common interface that other libraries can implement.
A downside of any approach for USB devices on Linux that isn't a kernel driver is that one or more udev rules will need to be added (as the article described). This also applies when using a device that uses a supported USB protocol, but has different IDs than the ones listed in the kernel driver.
[1] More devices fall into this category than you might expect. For example, Linux has an API for communicating with CAN devices called SocketCAN, so if you're writing a driver for a CAN device that connects via USB and exposes the full CAN bus over USB (maybe something that goes in or connects to a car), you should write a kernel driver that converts data between SocketCAN and whatever USB protocol is being used (assuming one doesn't already exist, a lot of USB CAN devices use protocols that already have drivers in the kernel). SocketCAN only exposes the raw data extracted from the CAN frames, so if you want to expose an easy way to control a particular CAN device, that belongs in a userspace library that uses the SocketCAN API under the hood.
I understood that reference
With questionable grammar: [https://rajiv256.github.io//projects/ouros/](link)