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Date:   Wed, 26 Apr 2023 16:41:17 +0200
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Subject: Re: [PATCH 0/6] Initial Rust V4L2 support
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To:     Hans Petter Selasky <hps@selasky.org>,
        Daniel Almeida <daniel.almeida@collabora.com>,
        wedsonaf@gmail.com, ojeda@kernel.org, mchehab@kernel.org,
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From:   "Enrico Weigelt, metux IT consult" <lkml@metux.net>
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On 10.04.23 20:59, Hans Petter Selasky wrote:

> Adding a dependency to build the Rust compiler even to build one or two 
> V4L2 device drivers, would mean a lot to my small hselasky/webcamd 
> project. It already has to fetch a copy of the Linux kernel, and now has 
> to bootstrap Rust from stage0 to stageN.

Did it ever cross your mind, being a bit thankful that you can use our
Linux code for your BSD project ?

Linux kernel code was never meant to be used anywhere outside the Linux
kernel. It's cool to see that such things are possible, but that's
really out of scope here.

> I personally say no. It's like 
> XCode unfortunately. I download 100's of GBytes of upgrades to XCode, 
> and barely upload one millionth worth of code back to Apple. It's not 
> good. Software developers shouldn't have to download more stuff than 
> they upload?

Where does the connection to Xcode come from ?

> Why not move Linux-V4L2 drivers to user-space? 

Feel free to send patches.

>> The reality is that it isn't up to anyone to say who should or
>> shouldn't become
>> a kernel developer. The resources are out there for anyone to try, and
>> if
>> maintainers take in their patches, then that's the end of the story.
> The GPLv2 license should not be the only reason behind Linux developers 
> putting drivers in the kernel-space. I think moving more stuff to 
> user-space would benefit a greater purpose.

I don't recall any specific case for the license being the primary
reason for putting someting into the kernel instead of userland.

If you want userland v4l drivers: feel free to send patches. Those
should also be capable of directly passing around HW buffers between
separate devices (eg. fg -> codec -> display), which often is
performance critical in embedded devices.


--mtx

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Enrico Weigelt, metux IT consult
Free software and Linux embedded engineering
info@metux.net -- +49-151-27565287