guides to board files -> device-tree and Android -> mainline?

guides to board files -> device-tree and Android -> mainline?

[Paul Wise]

Hi all,

Are there any guides for developers new to Linux for:

      * converting board files to device-tree
      * porting drivers and patches from Android to current mainline?

There are a lot of ARM mobile devices out there that aren't supported by
Linux mainline and having these guides available would really help
getting the usual Linux distros to support more mobile devices. Usually
the SoC is supported by mainline but the board is not, as is the case
for the device I have been trying to work on:

http://bonedaddy.net/pabs3/log/2012/12/03/debian-mobile/

-- 
bye,
pabs

http://bonedaddy.net/pabs3/
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guides to board files -> device-tree and Android -> mainline?

[Matthias Brugger]

Hi Paul,

2013/1/26 Paul Wise <pabs3@bonedaddy.net>:
> Hi all,
>
> Are there any guides for developers new to Linux for:
>
>       * converting board files to device-tree
>       * porting drivers and patches from Android to current mainline?

there are several parts of Android, which are not part of the mainline
kernel. Others are in staging. See
http://elinux.org/Android_Mainlining_Project for more details.

Regarding drivers for chips on your board, see the kernel
documentation about coding style
(http://lxr.free-electrons.com/source/Documentation/CodingStyle) and
submitting drivers
(http://lxr.free-electrons.com/source/Documentation/SubmittingDrivers),
submitting patches etc.

Beware to send the patches/drivers to the right mailing list (see the
MAINTAINERS file).

If you want to add the board itself and it is ARM based, then you have
to create a device tree file. I think the older board files are no
more accepted in the mainline kernel.

Hope that answered your question.
Cheers and happy hacking.
Matthias

>
> There are a lot of ARM mobile devices out there that aren't supported by
> Linux mainline and having these guides available would really help
> getting the usual Linux distros to support more mobile devices. Usually
> the SoC is supported by mainline but the board is not, as is the case
> for the device I have been trying to work on:
>
> http://bonedaddy.net/pabs3/log/2012/12/03/debian-mobile/
>
> --
> bye,
> pabs
>
> http://bonedaddy.net/pabs3/
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>



-- 
---
motzblog.wordpress.com

guides to board files -> device-tree and Android -> mainline?

[Paul Wise]

On Sat, 2013-01-26 at 16:13 +0100, Matthias Brugger wrote:

> there are several parts of Android....

Thanks for the pointers!

> If you want to add the board itself and it is ARM based, then you have
> to create a device tree file. I think the older board files are no
> more accepted in the mainline kernel.

I'm aware of that, my question was how do I convert existing board files
to device tree files? Is there an automated tool, or a guide for that?

-- 
bye,
pabs

http://bonedaddy.net/pabs3/
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guides to board files -> device-tree and Android -> mainline?

[Thomas Petazzoni]

Dear Paul Wise,

On Tue, 29 Jan 2013 09:43:28 +0800, Paul Wise wrote:

> > If you want to add the board itself and it is ARM based, then you have
> > to create a device tree file. I think the older board files are no
> > more accepted in the mainline kernel.
> 
> I'm aware of that, my question was how do I convert existing board files
> to device tree files? Is there an automated tool, or a guide for that?

No, there is no automated tool, because it is not possible to do that
automatically. The device drivers used by your board must have a Device
Tree binding, and writing the Device Tree source cannot directly be
done from the C board file. It requires human knowledge and
intervention.

Could you be more specific about the platform you would look to convert
to the Device Tree? Where is the existing source code?

Best regards,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

guides to board files -> device-tree and Android -> mainline?

[Paul Wise]

On Tue, 2013-01-29 at 15:51 +0100, Thomas Petazzoni wrote:

> No, there is no automated tool, because it is not possible to do that
> automatically. The device drivers used by your board must have a Device
> Tree binding, and writing the Device Tree source cannot directly be
> done from the C board file. It requires human knowledge and
> intervention.

I see, is there at least a guide for the conversion?

> Could you be more specific about the platform you would look to convert
> to the Device Tree? Where is the existing source code?

Many devices with an ARM SoC and or an Android kernel aren't fully
supported by mainline. The devices that I own in this situation are the
OpenMoko FreeRunner (gta02) and the Samsung Galaxy S (galaxysmtd).

gta02:
git://git.openmoko.org/git/kernel.git
git://github.com/shr-distribution/linux.git

galaxysmtd (and a bunch of other devices):
git://gitorious.org/replicant/kernel_samsung_aries.git

-- 
bye,
pabs

http://bonedaddy.net/pabs3/
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