[linux-dvb] Multiple em28xx devices

[linux-dvb] Multiple em28xx devices

[rvf16]

Hello.

I am trying to use two Terratec Cinergy Hybrid T USB XS FM tuners, at 
the same time, on the same system.
Both work great when used solely.
When used simultaneously the second one gives the following error :

v4l2: unable to open '/dev/video1': No space left on device

I am using the em28xx-new-b2e841c05e94 driver from 
http://mcentral.de/hg/~mrec/em28xx-new on a Fedora 6 system.
I have opened this topic in the em28xx mailing list 
http://mcentral.de/pipermail/em28xx/ but it seems it is not maintained 
any more.

According to comments on relevant problems (the following is for spca5xx 
driver for cameras with same problem) :
-----------------------
When other USB devices are present on the same host controller bus as 
the camera, the bandwidth requirements of the spca5xx driver are not 
being met, with some hardware configurations.
The spca5xx driver is asking for more bandwidth than is available which 
results in these error messages.
-----------------------

We are, under these circumstances, advised to either insert the device 
in another USB socket or even install a PCI card with extra USB sockets 
so that the device ends up in different bus.
I tried to insert the second device in another usb socket but it always 
ends up at the same bus with the first one :

#lsusb
Bus 005 Device 014: ID 0ccd:0072 TerraTec Electronic GmbH
Bus 005 Device 015: ID 0ccd:0072 TerraTec Electronic GmbH
Bus 005 Device 001: ID 0000:0000 Bus 002 Device 006: ID 046d:c50e 
Logitech, Inc. MX-1000 Cordless Mouse Receiver
Bus 002 Device 001: ID 0000:0000 Bus 004 Device 001: ID 0000:0000 Bus 
003 Device 001: ID 0000:0000 Bus 001 Device 001: ID 0000:0000
which happens to a lot of people from what i have seen.

As this is a laptop with 4 USB sockets :

# lspci | grep USB
00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI 
#1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI 
#2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI 
#3 (rev 01)
00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI 
#4 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI 
Controller (rev 01)

i cannot install a PCI card with extra USB sockets so there goes 
workaround number two.

In spca5xx case a developer patched the driver so that the bandwidth was 
throttled in such a way that two devices used simultaneously would never 
exceed maximum.

Can that be done with em28xx?
If not, is there any other workaround to this problem?

Thank you.
Regards.



_______________________________________________
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For V4L/DVB development, please use instead linux-media@vger.kernel.org
linux-dvb@linuxtv.org
http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb

Re: [linux-dvb] Multiple em28xx devices

[Douglas Schilling Landgraf]

Hello rvf16,

On Thu, 09 Apr 2009 17:05:36 +0300
rvf16 <rvf16@yahoo.gr> wrote:

> Hello.
> 
> I am trying to use two Terratec Cinergy Hybrid T USB XS FM tuners, at 
> the same time, on the same system.
> Both work great when used solely.
> When used simultaneously the second one gives the following error :
> 
> v4l2: unable to open '/dev/video1': No space left on device
> 
> I am using the em28xx-new-b2e841c05e94 driver from 
> http://mcentral.de/hg/~mrec/em28xx-new on a Fedora 6 system.
> I have opened this topic in the em28xx mailing list 
> http://mcentral.de/pipermail/em28xx/ but it seems it is not
> maintained any more.
> 
> According to comments on relevant problems (the following is for
> spca5xx driver for cameras with same problem) :
> -----------------------
> When other USB devices are present on the same host controller bus as 
> the camera, the bandwidth requirements of the spca5xx driver are not 
> being met, with some hardware configurations.
> The spca5xx driver is asking for more bandwidth than is available
> which results in these error messages.
> -----------------------
> 
> We are, under these circumstances, advised to either insert the
> device in another USB socket or even install a PCI card with extra
> USB sockets so that the device ends up in different bus.
> I tried to insert the second device in another usb socket but it
> always ends up at the same bus with the first one :
> 
> #lsusb
> Bus 005 Device 014: ID 0ccd:0072 TerraTec Electronic GmbH
> Bus 005 Device 015: ID 0ccd:0072 TerraTec Electronic GmbH
> Bus 005 Device 001: ID 0000:0000 Bus 002 Device 006: ID 046d:c50e 
> Logitech, Inc. MX-1000 Cordless Mouse Receiver
> Bus 002 Device 001: ID 0000:0000 Bus 004 Device 001: ID 0000:0000 Bus 
> 003 Device 001: ID 0000:0000 Bus 001 Device 001: ID 0000:0000
> which happens to a lot of people from what i have seen.
> 
> As this is a laptop with 4 USB sockets :
> 
> # lspci | grep USB
> 00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB
> UHCI #1 (rev 01)
> 00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB
> UHCI #2 (rev 01)
> 00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB
> UHCI #3 (rev 01)
> 00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB
> UHCI #4 (rev 01)
> 00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2
> EHCI Controller (rev 01)
> 
> i cannot install a PCI card with extra USB sockets so there goes 
> workaround number two.
> 
> In spca5xx case a developer patched the driver so that the bandwidth
> was throttled in such a way that two devices used simultaneously
> would never exceed maximum.
> 
> Can that be done with em28xx?
> If not, is there any other workaround to this problem?

Please use upstream repository, we do not support sources from
http://mcentral.de/hg/~mrec/em28xx-new this is a parallel project.

For additional info how to download upstream tree see:
http://www.linuxtv.org/wiki/index.php/How_to_Obtain%2C_Build_and_Install_V4L-DVB_Device_Drivers

Cheers,
Douglas

Re: [linux-dvb] Multiple em28xx devices

[Devin Heitmueller]

On Thu, Apr 9, 2009 at 10:14 AM, Douglas Schilling Landgraf
> Please use upstream repository, we do not support sources from
> http://mcentral.de/hg/~mrec/em28xx-new this is a parallel project.
>
> For additional info how to download upstream tree see:
> http://www.linuxtv.org/wiki/index.php/How_to_Obtain%2C_Build_and_Install_V4L-DVB_Device_Drivers
>
> Cheers,
> Douglas

Douglas,

Unless he is willing to do without dvb support, he's not going to be
able to use the upstream em28xx driver with the Terratec XS.  I've got
a device being mailed to me, at which point I will be able to get the
dvb support working.

Devin

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

Re: [linux-dvb] Multiple em28xx devices

[Douglas Schilling Landgraf]

Hello Devin,

On Thu, 9 Apr 2009 10:20:33 -0400
Devin Heitmueller <devin.heitmueller@gmail.com> wrote:

> On Thu, Apr 9, 2009 at 10:14 AM, Douglas Schilling Landgraf
> > Please use upstream repository, we do not support sources from
> > http://mcentral.de/hg/~mrec/em28xx-new this is a parallel project.
> >
> > For additional info how to download upstream tree see:
> > http://www.linuxtv.org/wiki/index.php/How_to_Obtain%2C_Build_and_Install_V4L-DVB_Device_Drivers
> >
> > Cheers,
> > Douglas
> 
> Douglas,
> 
> Unless he is willing to do without dvb support, he's not going to be
> able to use the upstream em28xx driver with the Terratec XS.  

The idea behind that email is to inform that we do not support any
parallel project. 

> I've got
> a device being mailed to me, at which point I will be able to get the
> dvb support working.

Great, good news!

Cheers,
Douglas

Re: [linux-dvb] Multiple em28xx devices

[Markus Rechberger]

On Thu, Apr 9, 2009 at 4:05 PM, rvf16 <rvf16@yahoo.gr> wrote:
> Hello.
>
> I am trying to use two Terratec Cinergy Hybrid T USB XS FM tuners, at
> the same time, on the same system.
> Both work great when used solely.
> When used simultaneously the second one gives the following error :
>
> v4l2: unable to open '/dev/video1': No space left on device
>
> I am using the em28xx-new-b2e841c05e94 driver from
> http://mcentral.de/hg/~mrec/em28xx-new on a Fedora 6 system.
> I have opened this topic in the em28xx mailing list
> http://mcentral.de/pipermail/em28xx/ but it seems it is not maintained
> any more.
>

hmm I'll check this there has been an update of the mailsystem on that
box recently.

> According to comments on relevant problems (the following is for spca5xx
> driver for cameras with same problem) :
> -----------------------
> When other USB devices are present on the same host controller bus as
> the camera, the bandwidth requirements of the spca5xx driver are not
> being met, with some hardware configurations.
> The spca5xx driver is asking for more bandwidth than is available which
> results in these error messages.
> -----------------------
>
> We are, under these circumstances, advised to either insert the device
> in another USB socket or even install a PCI card with extra USB sockets
> so that the device ends up in different bus.
> I tried to insert the second device in another usb socket but it always
> ends up at the same bus with the first one :
>
> #lsusb
> Bus 005 Device 014: ID 0ccd:0072 TerraTec Electronic GmbH
> Bus 005 Device 015: ID 0ccd:0072 TerraTec Electronic GmbH
> Bus 005 Device 001: ID 0000:0000 Bus 002 Device 006: ID 046d:c50e
> Logitech, Inc. MX-1000 Cordless Mouse Receiver
> Bus 002 Device 001: ID 0000:0000 Bus 004 Device 001: ID 0000:0000 Bus
> 003 Device 001: ID 0000:0000 Bus 001 Device 001: ID 0000:0000
> which happens to a lot of people from what i have seen.
>
> As this is a laptop with 4 USB sockets :
>
> # lspci | grep USB
> 00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
> #1 (rev 01)
> 00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
> #2 (rev 01)
> 00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
> #3 (rev 01)
> 00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
> #4 (rev 01)
> 00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI
> Controller (rev 01)
>
> i cannot install a PCI card with extra USB sockets so there goes
> workaround number two.
>

you can simply try to load the em28xx with alt=3

modprobe em28xx alt=3

as long as the bus is not fully utilized this should work fine!
remember you only have 480 mbit; analog TV at least requires up to 170
mbit for 1 device.

cheers,
Markus
> In spca5xx case a developer patched the driver so that the bandwidth was
> throttled in such a way that two devices used simultaneously would never
> exceed maximum.
>
> Can that be done with em28xx?
> If not, is there any other workaround to this problem?
>
> Thank you.
> Regards.
>
>
>
> _______________________________________________
> linux-dvb users mailing list
> For V4L/DVB development, please use instead linux-media@vger.kernel.org
> linux-dvb@linuxtv.org
> http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
>