Strange USB behavior

Strange USB behavior

[Chris Tapp]

I'm running on a platform using the Vortex86DX SoC which includes a  
CM119 USB audio interface.

I've got a kernel configuration that recognizes and initializes this  
ok (dmesg reports it as an ALSA device). However, this is only the  
case if I also have a USB storage device connected when it boots!

1) The audio works if I boot the kernel from the USB device;
2) The audio works if I boot from the system SD card and any USB  
storage device is connected (it's not booting from this accidentally);
3) The audio does not work if I boot from the SD card without a USB  
storage device.

Can anyone give me an idea where I should start looking to try and  
understand what's going on here?

Kernel is a modified 'common-pc' 2.6.34 wrs that has been built using  
Yocto 0.9.

Chris Tapp

opensource@keylevel.com
www.keylevel.com

Re: Strange USB behavior

[Chris Tapp]

On 18 Aug 2011, at 09:19, Chris Tapp wrote:

> I'm running on a platform using the Vortex86DX SoC which includes a  
> CM119 USB audio interface.
>
> I've got a kernel configuration that recognizes and initializes this  
> ok (dmesg reports it as an ALSA device). However, this is only the  
> case if I also have a USB storage device connected when it boots!
>
> 1) The audio works if I boot the kernel from the USB device;
> 2) The audio works if I boot from the system SD card and any USB  
> storage device is connected (it's not booting from this accidentally);
> 3) The audio does not work if I boot from the SD card without a USB  
> storage device.
>
> Can anyone give me an idea where I should start looking to try and  
> understand what's going on here?
>
> Kernel is a modified 'common-pc' 2.6.34 wrs that has been built  
> using Yocto 0.9.

Looks like this is just a kernel load order issue.

The USB storage device seems to cause the sound device to initialise  
earlier in the boot so it's ready when ALSA loads. Without it, it's  
not loaded before ALSA, so a 'No sound card' message is produced in  
the log - but there is one once the system is up.

Chris Tapp

opensource@keylevel.com
www.keylevel.com

Re: Strange USB behavior

[Bruce Ashfield]

On 11-08-18 3:36 PM, Chris Tapp wrote:
> On 18 Aug 2011, at 09:19, Chris Tapp wrote:
>
>> I'm running on a platform using the Vortex86DX SoC which includes a
>> CM119 USB audio interface.
>>
>> I've got a kernel configuration that recognizes and initializes this
>> ok (dmesg reports it as an ALSA device). However, this is only the
>> case if I also have a USB storage device connected when it boots!
>>
>> 1) The audio works if I boot the kernel from the USB device;
>> 2) The audio works if I boot from the system SD card and any USB
>> storage device is connected (it's not booting from this accidentally);
>> 3) The audio does not work if I boot from the SD card without a USB
>> storage device.
>>
>> Can anyone give me an idea where I should start looking to try and
>> understand what's going on here?
>>
>> Kernel is a modified 'common-pc' 2.6.34 wrs that has been built using
>> Yocto 0.9.
>
> Looks like this is just a kernel load order issue.
>
> The USB storage device seems to cause the sound device to initialise
> earlier in the boot so it's ready when ALSA loads. Without it, it's not
> loaded before ALSA, so a 'No sound card' message is produced in the log
> - but there is one once the system is up.

Aha. We've seen similar things here over the years. At least
this doesn't sound like it caused too much pain.

Cheers,

Bruce

>
> Chris Tapp
>
> opensource@keylevel.com
> www.keylevel.com
>
>
>
> _______________________________________________
> yocto mailing list
> yocto@yoctoproject.org
> https://lists.yoctoproject.org/listinfo/yocto

Re: Strange USB behavior

[Darren Hart]

On 08/18/2011 12:36 PM, Chris Tapp wrote:
> On 18 Aug 2011, at 09:19, Chris Tapp wrote:
> 
>> I'm running on a platform using the Vortex86DX SoC which includes a  
>> CM119 USB audio interface.
>>
>> I've got a kernel configuration that recognizes and initializes this  
>> ok (dmesg reports it as an ALSA device). However, this is only the  
>> case if I also have a USB storage device connected when it boots!
>>
>> 1) The audio works if I boot the kernel from the USB device;
>> 2) The audio works if I boot from the system SD card and any USB  
>> storage device is connected (it's not booting from this accidentally);
>> 3) The audio does not work if I boot from the SD card without a USB  
>> storage device.
>>
>> Can anyone give me an idea where I should start looking to try and  
>> understand what's going on here?
>>
>> Kernel is a modified 'common-pc' 2.6.34 wrs that has been built  
>> using Yocto 0.9.
> 
> Looks like this is just a kernel load order issue.
> 
> The USB storage device seems to cause the sound device to initialise  
> earlier in the boot so it's ready when ALSA loads. Without it, it's  
> not loaded before ALSA, so a 'No sound card' message is produced in  
> the log - but there is one once the system is up.
> 

I asked Sarah Sharp if she had any thoughts, she responded in part:

One thing I might suspect is a problem with the host controller going
into suspend.  I think 2.6.34 didn't have support for USB suspend for
mass storage devices, so booting with a mass storage device would keep
the USB host controller from going into suspend.  This would also be
true of mice, since they did support suspend in 2.6.34, but it was
disabled by default.

Does it help if he disables USB device suspend in the kernel config?

--
Darren

> Chris Tapp
> 
> opensource@keylevel.com
> www.keylevel.com
> 
> 
> 
> _______________________________________________
> yocto mailing list
> yocto@yoctoproject.org
> https://lists.yoctoproject.org/listinfo/yocto

-- 
Darren Hart
Intel Open Source Technology Center
Yocto Project - Linux Kernel

Re: Strange USB behavior

[Chris Tapp]

On 18 Aug 2011, at 22:06, Darren Hart wrote:

> I asked Sarah Sharp if she had any thoughts, she responded in part:
>
> One thing I might suspect is a problem with the host controller going
> into suspend.  I think 2.6.34 didn't have support for USB suspend for
> mass storage devices, so booting with a mass storage device would keep
> the USB host controller from going into suspend.  This would also be
> true of mice, since they did support suspend in 2.6.34, but it was
> disabled by default.
>
> Does it help if he disables USB device suspend in the kernel config?

I'll give it a try (will be a while as I've moved to the 5.0.1 release  
and the build has just started!).

Thanks for the suggestion :-)

Chris Tapp

opensource@keylevel.com
www.keylevel.com

strange usb behavior

[Jaap de Jong]

Hi All!

I'm observing some strange usb behavior.
I have a board with an onboard ftdi usb chip acting as 2 rs232 ports.
And I have on the same board an external usb device with again a ftdi 
chip on board, this time acting as a single rs485 port.

    Build Configuration:
    BB_VERSION        = "1.8.18"
    METADATA_BRANCH   = "release-2010.12"
    METADATA_REVISION = "dec3967"
    TARGET_ARCH       = "arm"
    TARGET_OS         = "linux-gnueabi"
    MACHINE           = "at91sam9263ek-special"
    DISTRO            = "angstrom"
    DISTRO_VERSION    = "2010.7-test-20101210"
    TARGET_FPU        = "soft"

So when I boot with the external device in the connector the internal 
and external devices are detected as expected.

     [    1.280000] usb 1-1: new full speed USB device using at91_ohci 
and address 2
     [    1.460000] usb 1-1: configuration #1 chosen from 1 choice
     [    1.470000] ftdi_sio 1-1:1.0: FTDI USB Serial Device converter 
detected
     [    1.470000] usb 1-1: Detected FT2232C
     [    1.480000] usb 1-1: Number of endpoints 2
     [    1.480000] usb 1-1: Endpoint 1 MaxPacketSize 64
     [    1.490000] usb 1-1: Endpoint 2 MaxPacketSize 64
     [    1.490000] usb 1-1: Setting MaxPacketSize 64
     [    1.500000] usb 1-1: FTDI USB Serial Device converter now 
attached to ttyUSB0
     [    1.510000] ftdi_sio 1-1:1.1: FTDI USB Serial Device converter 
detected
     [    1.510000] usb 1-1: Detected FT2232C
     [    1.520000] usb 1-1: Number of endpoints 2
     [    1.520000] usb 1-1: Endpoint 1 MaxPacketSize 64
     [    1.530000] usb 1-1: Endpoint 2 MaxPacketSize 64
     [    1.530000] usb 1-1: Setting MaxPacketSize 64
     [    1.540000] usb 1-1: FTDI USB Serial Device converter now 
attached to ttyUSB1
     [    1.680000] usb 1-2: new full speed USB device using at91_ohci 
and address 3
     [    1.860000] usb 1-2: configuration #1 chosen from 1 choice
     [    1.870000] ftdi_sio 1-2:1.0: FTDI USB Serial Device converter 
detected
     [    1.880000] usb 1-2: Detected FT232RL
     [    1.880000] usb 1-2: Number of endpoints 2
     [    1.890000] usb 1-2: Endpoint 1 MaxPacketSize 64
     [    1.890000] usb 1-2: Endpoint 2 MaxPacketSize 64
     [    1.900000] usb 1-2: Setting MaxPacketSize 64
     [    1.900000] usb 1-2: FTDI USB Serial Device converter now 
attached to ttyUSB2


But if I look at the /dev directory ttyUSB2 is missing!

     # ls -l /dev/ttyU*
         crw-rw----    1 root     dialout  188,   0 Jan  1  1970 
/dev/ttyUSB0
         crw-rw----    1 root     dialout  188,   1 Jan  1  1970 
/dev/ttyUSB1

     # lsusb
         Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
         Bus 001 Device 002: ID 0403:6010 Future Technology Devices 
International, Ltd FT2232C Dual USB-UART/FIFO IC
         Bus 001 Device 003: ID 0403:6001 Future Technology Devices 
International, Ltd FT232 USB-Serial (UART) IC

So, why is ttyUSB2 gone and are ttyUSB[01] still available??

If I then remove (mark the second line!)

     [  103.600000] usb 1-2: USB disconnect, address 3
     [  103.610000] ftdi_sio ttyUSB2: FTDI USB Serial Device converter 
now disconnected from ttyUSB2
     [  103.630000] ftdi_sio 1-2:1.0: device disconnected

and re-enter the external device life is OK!

     [  140.020000] usb 1-2: new full speed USB device using at91_ohci 
and address 4
     [  140.200000] usb 1-2: configuration #1 chosen from 1 choice
     [  140.230000] ftdi_sio 1-2:1.0: FTDI USB Serial Device converter 
detected
     [  140.250000] usb 1-2: Detected FT232RL
     [  140.250000] usb 1-2: Number of endpoints 2
     [  140.250000] usb 1-2: Endpoint 1 MaxPacketSize 64
     [  140.260000] usb 1-2: Endpoint 2 MaxPacketSize 64
     [  140.260000] usb 1-2: Setting MaxPacketSize 64
     [  140.270000] usb 1-2: FTDI USB Serial Device converter now 
attached to ttyUSB2

     # ls -l /dev/ttyU*
         crw-rw----    1 root     dialout  188,   0 Jan  1  1970 
/dev/ttyUSB0
         crw-rw----    1 root     dialout  188,   1 Jan  1  1970 
/dev/ttyUSB1
         crw-rw----    1 root     dialout  188,   2 Dec 10 02:18 
/dev/ttyUSB2

     # lsusb
         Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
         Bus 001 Device 002: ID 0403:6010 Future Technology Devices 
International, Ltd FT2232C Dual USB-UART/FIFO IC
         Bus 001 Device 004: ID 0403:6001 Future Technology Devices 
International, Ltd FT232 USB-Serial (UART) IC

Any ideas??

Thanks!
Jaap