4vl + usb + arm

4vl + usb + arm

[Paul Thomas]

Hello, is anyone using a USB v4l device on an arm processor?

thanks,
Paul

Re: 4vl + usb + arm

[Pete Eberlein]

On Tue, 2009-03-03 at 11:51 -0700, Paul Thomas wrote:
> Hello, is anyone using a USB v4l device on an arm processor?

While I haven't used a USB video device on an ARM board, I have tried
cross compiling the v4l sources for ARM.  Here's what I found:

The v4l/Makefile.media uses the host strip binary on the ARM .ko files,
which doesn't work.  It could use $(CROSS_COMPILE)strip instead.  I
worked around the problem using a strip soft-link to arm-eabi-strip in
my cross tools bin directory.

The v4l/firmware/Makefile assumes /lib/firmware, this could be
$(DESTDIR)/lib/firmware instead.

Here are the make commands I used to build the v4l tree:

PATH=/path/to/devkitARM/bin:$PATH make ARCH=arm CROSS_COMPILE=arm-eabi-
SRCDIR=/path/to/arm/kernel-src

PATH=/path/to/devkitARM/bin:$PATH make ARCH=arm CROSS_COMPILE=arm-eabi-
DESTDIR=/path/to/arm/sysroot install

I'd like to know if modules built this way work on actual hardware.

Regards.
-- 
Pete Eberlein
Sensoray Co., Inc.
Email: pete@sensoray.com
http://www.sensoray.com

Re: 4vl + usb + arm

[Paul Thomas]

On Tue, Mar 17, 2009 at 2:58 PM, Pete Eberlein <pete@sensoray.com> wrote:
> On Tue, 2009-03-03 at 11:51 -0700, Paul Thomas wrote:
>> Hello, is anyone using a USB v4l device on an arm processor?
>
> While I haven't used a USB video device on an ARM board, I have tried
> cross compiling the v4l sources for ARM.  Here's what I found:
>
> The v4l/Makefile.media uses the host strip binary on the ARM .ko files,
> which doesn't work.  It could use $(CROSS_COMPILE)strip instead.  I
> worked around the problem using a strip soft-link to arm-eabi-strip in
> my cross tools bin directory.
>
> The v4l/firmware/Makefile assumes /lib/firmware, this could be
> $(DESTDIR)/lib/firmware instead.
>
> Here are the make commands I used to build the v4l tree:
>
> PATH=/path/to/devkitARM/bin:$PATH make ARCH=arm CROSS_COMPILE=arm-eabi-
> SRCDIR=/path/to/arm/kernel-src
>
> PATH=/path/to/devkitARM/bin:$PATH make ARCH=arm CROSS_COMPILE=arm-eabi-
> DESTDIR=/path/to/arm/sysroot install
>
> I'd like to know if modules built this way work on actual hardware.
>
> Regards.
> --
> Pete Eberlein
> Sensoray Co., Inc.
> Email: pete@sensoray.com
> http://www.sensoray.com
>
>

Pete,

I've been able to get the v4l tree to compile fine. I use the "make
release DIR=" to set the kernel DIR then make with the normal ARCH=
and CROSS_COMPILE=, and this seems to work correctly. Since I posted
we've had some limited success getting v4l devices working with arm.
The main problem now seems to be that the processor we're using
(at91rm9200) doesn't have a high-speed USB host.

I've been talking with some of the folks at sensoray (Danil &
Konstantin) about getting the 2251 or 2255 to work on our arm board.

thanks,
Paul

Re: 4vl + usb + arm

[Devin Heitmueller]

On Tue, Mar 17, 2009 at 5:58 PM, Pete Eberlein <pete@sensoray.com> wrote:
> The v4l/Makefile.media uses the host strip binary on the ARM .ko files,
> which doesn't work.  It could use $(CROSS_COMPILE)strip instead.  I
> worked around the problem using a strip soft-link to arm-eabi-strip in
> my cross tools bin directory.

I ran into the issue with strip, and just worked around it by putting
the cross compiler's bin directory into the path.  If you have a patch
though that fixes it the "right" way, feel free to submit a patch.

> I'd like to know if modules built this way work on actual hardware.

Generally speaking, yes they do work.  I did some work with a couple
of different devices under ARM, and although there are bugs (which I
am preparing patches for), the drivers basically worked as expected.

Regards,

Devin

-- 
Devin J. Heitmueller
http://www.devinheitmueller.com
AIM: devinheitmueller