choppy audio on ARM

choppy audio on ARM

[Rafael Seste]

Hi all,

A couple of months ago I sent a email about a problem with the
bluetooth audio on a ARM platform. I have a choppy audio on the
incoming stream. I still didn't solve this problem but I found a setup
that this problem doesn't happens.

My ARM device has only one USB port, so I always connect the BT dongle
in this port. Last week I bought a USB hub and plug it into the usb
and the BT dongle in the hub. Miraculously this problem disappeared. I
removed the hub and tried again and the problem returns.

Does anybody has any clue why the USB hub "fixed" this choppy audio???
Does it use a different USB drivers?

tks in advance

-- 
Rafael S. Seste

Re: choppy audio on ARM

[Douglas Lopes Pereira]

Hi,

On Fri, Sep 4, 2009 at 1:42 PM, Rafael Seste <rseste@gmail.com> wrote:
>
> Hi all,
>
> A couple of months ago I sent a email about a problem with the
> bluetooth audio on a ARM platform. I have a choppy audio on the
> incoming stream. I still didn't solve this problem but I found a setup
> that this problem doesn't happens.
>
> My ARM device has only one USB port, so I always connect the BT dongle
> in this port. Last week I bought a USB hub and plug it into the usb
> and the BT dongle in the hub. Miraculously this problem disappeared. I
> removed the hub and tried again and the problem returns.
>
> Does anybody has any clue why the USB hub "fixed" this choppy audio???
> Does it use a different USB drivers?
>
> tks in advance
>
> --
> Rafael S. Seste
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

does anyone has more information on that?

I have the same scenario here. Same kernel modules loaded but audio
only works if my bluetooth dongle is connected on my external
self-powered USB Hub.

Check out dmesg output:

- Connecting bluetooth dongle over USB Hub:

usb 1-1: new high speed USB device using orion-ehci and address 19
usb 1-1: configuration #1 chosen from 1 choice
hub 1-1:1.0: USB hub found
hub 1-1:1.0: 4 ports detected
usb 1-1.3: new full speed USB device using orion-ehci and address 20
usb 1-1.3: configuration #1 chosen from 1 choice

- Connecting bluetooth directly on Sheeva Plug:

usb 1-1: new full speed USB device using orion-ehci and address 14
usb 1-1: configuration #1 chosen from 1 choice

The only difference is the high device speed device which is my USB Hub.

Can anyone help me to understand what is happening?

Thanks,
Douglas

Re: choppy audio on ARM

[Brad Midgley]

Douglas

> - Connecting bluetooth dongle over USB Hub:
>
> usb 1-1: new high speed USB device using orion-ehci and address 19
> usb 1-1: configuration #1 chosen from 1 choice
> hub 1-1:1.0: USB hub found
> hub 1-1:1.0: 4 ports detected
> usb 1-1.3: new full speed USB device using orion-ehci and address 20
> usb 1-1.3: configuration #1 chosen from 1 choice
>
> - Connecting bluetooth directly on Sheeva Plug:
>
> usb 1-1: new full speed USB device using orion-ehci and address 14
> usb 1-1: configuration #1 chosen from 1 choice

"lsusb" in both cases should shed more light on the topology and where
full speed links creep in.

-- 
Brad Midgley

Re: choppy audio on ARM

[Douglas Lopes Pereira]

Hi Brad,

On Mon, Sep 14, 2009 at 5:47 PM, Brad Midgley <bmidgley@gmail.com> wrote:
> Douglas
>
>> - Connecting bluetooth dongle over USB Hub:
>>
>> usb 1-1: new high speed USB device using orion-ehci and address 19
>> usb 1-1: configuration #1 chosen from 1 choice
>> hub 1-1:1.0: USB hub found
>> hub 1-1:1.0: 4 ports detected
>> usb 1-1.3: new full speed USB device using orion-ehci and address 20
>> usb 1-1.3: configuration #1 chosen from 1 choice
>>
>> - Connecting bluetooth directly on Sheeva Plug:
>>
>> usb 1-1: new full speed USB device using orion-ehci and address 14
>> usb 1-1: configuration #1 chosen from 1 choice
>
> "lsusb" in both cases should shed more light on the topology and where
> full speed links creep in.
>
> --
> Brad Midgley
>

Could you elaborate a little bit more on that?

Thank you.

Re: choppy audio on ARM

[Douglas Lopes Pereira]

Hi Brad

On Tue, Sep 15, 2009 at 2:00 PM, Brad Midgley <bmidgley@gmail.com> wrote:
> Douglas,
>
> run "lsusb" from a shell after the adapters are all connected.
>
> Brad
>
> On Tue, Sep 15, 2009 at 7:14 AM, Douglas Lopes Pereira
> <douglaslopespereira@gmail.com> wrote:
>> Hi Brad,
>>
>> On Mon, Sep 14, 2009 at 5:47 PM, Brad Midgley <bmidgley@gmail.com> wrote:
>>> Douglas
>>>
>>>> - Connecting bluetooth dongle over USB Hub:
>>>>
>>>> usb 1-1: new high speed USB device using orion-ehci and address 19
>>>> usb 1-1: configuration #1 chosen from 1 choice
>>>> hub 1-1:1.0: USB hub found
>>>> hub 1-1:1.0: 4 ports detected
>>>> usb 1-1.3: new full speed USB device using orion-ehci and address 20
>>>> usb 1-1.3: configuration #1 chosen from 1 choice
>>>>
>>>> - Connecting bluetooth directly on Sheeva Plug:
>>>>
>>>> usb 1-1: new full speed USB device using orion-ehci and address 14
>>>> usb 1-1: configuration #1 chosen from 1 choice
>>>
>>> "lsusb" in both cases should shed more light on the topology and where
>>> full speed links creep in.
>>>
>>> --
>>> Brad Midgley
>>>
>>
>> Could you elaborate a little bit more on that?
>>
>> Thank you.
>>
>
>
>
> --
> Brad Midgley
>

This is the output from lsusb. No interesting information in my point of view:

- Connecting bluetooth directly on Sheeva Plug:

Bus 001 Device 014: ID 0a12:0001 Cambridge Silicon Radio, Ltd
Bluetooth Dongle (HCI mode)
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

- Connecting bluetooth dongle over USB Hub:

Bus 001 Device 008: ID 0a12:0001 Cambridge Silicon Radio, Ltd
Bluetooth Dongle (HCI mode)
Bus 001 Device 002: ID 05e3:0606 Genesys Logic, Inc. USB 2.0 Hub /
D-Link DUB-H4 USB 2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Can you or someone else cite differences between EHCI driver handling
the usb dongle over the usb hub or directly connected?

Thank you for your patience and attention.

Douglas