Creative X-Fi USB 5.1 Driver

Creative X-Fi USB 5.1 Driver

[Mandar Joshi]

Hello,
   I walked through the code for snd-usb-audio and have a fair idea about the structure of the driver. I also
went through the "writing-an-alsa-driver" article on http://www.alsa-project.org
   Here is the stuff I've done so far http://mndar.phpnet.us/usbxfi/ .The link contains the "lsusb -v" output for the Creative USB X-Fi 5.1 . 
The xfi-0.0.0.0.tar.bz2 has the basic structure of an alsa driver (copied from the caiaq usb driver). It presently just loads the module when the card is connected.
Output in /var/log/messages
-------------------------------------------
Jan 30 10:46:29 mandar Found Creative USB X-Fi 5.1!!
Jan 30 10:46:29 mandar 0 041e:3042
Jan 30 10:46:29 mandar Found Creative USB X-Fi 5.1!!
Jan 30 10:46:29 mandar 0 041e:3042
Jan 30 10:46:29 mandar Found Creative USB X-Fi 5.1!!
Jan 30 10:46:29 mandar 0 041e:3042
Jan 30 10:46:29 mandar usbcore: registered new interface driver snd-usb-xfi
--------------------------------------------------------------------------------
As you can see, the probe is being called 3 times. Can someone please go through the source and let me know if I'm headed in the right direction?
I'm a newbie to alsa driver development and would really appreciate any input from you guys.
Also, please have a look the creative.txt file in the link. Its the 'lsusb -v' output for the card. How exactly do I interpret and use this information?

Regards
Mandar Joshi

Creative X-Fi USB 5.1 Driver

[Mandar Joshi]

Hello,

I used SniffUSB to capture the packets sent to the usb X-fi. I've uploaded it here http://mndar.phpnet.us/usbxfi/
I'm not very sure how to interpret the log. By looking at the log, can we tell if it conforms to the USB Audio spec?

Regards
Mandar Joshi
________________________________
Have you been here yet ? http://mndar.phpnet.us

Creative X-Fi USB 5.1 Driver

[Mandar Joshi]

Hello,

I was reading the USB Audio Specs from http://www.usb.org/developers/devclass_docs
The document talks about Effect Unit Descriptors and few other descriptors.There is no mention of such descriptors in the 'lsusb -v' output for the USB X-Fi 5.1
Does this mean thet the X-Fi,Crystalizer features of the USB X-Fi are implemented purely in software?
Here is a link to the lsusb output http://mndar.phpnet.us/usbxfi/files/creative.txt

The document "Audio20 final.pdf" also mentions that bDeviceClass, bDeviceSubClass and bDeviceProtocol should have values 0xEF, 0x02, and 0x01 respectively but in the 'lsusb -v' output all three values are 0. Any idea why it is so?

Regards
Mandar Joshi

Creative X-Fi USB 5.1 Driver

[Mandar Joshi]

>>Does this mean thet the X-Fi,Crystalizer features of the USB X-Fi are implemented purely in software?
I think this might be the case. 
I started SniffUSB under WindowsXP and tried changing the settings using 
the audio console software provided by Creative. 

When changing the Speaker selection (2.1/4.1/5.1), data is sent over usb to the device.
However, when I try to change the settings for the X-Fi Crystalizer or EAX or CMSS-3D or Graphic Equalizer
nothing gets sent to the device but the audio output does change and I am able to hear the corresponding effects.

And as mentioned in my previous post, the lsusb output doesn't show any effect descriptors or feature units

If this is in fact true that all the xtreme fidelity(X-Fi) stuff is happening in software alone, my purchase has been 
a total waste!! Does anybody on this list have a USB X-Fi 5.1 that they can use to verify my observations?

BTW, the mailing list seems to be creating separate threads for every post I make even though 
the subject line is the same. What am I missing? I'm using Yahoo Mail.

Regards
Mandar Joshi

Re: Creative X-Fi USB 5.1 Driver

[Lee Revell]

On Wed, Feb 4, 2009 at 11:57 AM, Mandar Joshi <emailmandar@yahoo.com> wrote:
>>>Does this mean thet the X-Fi,Crystalizer features of the USB X-Fi are implemented purely in software?
> I think this might be the case.
> I started SniffUSB under WindowsXP and tried changing the settings using
> the audio console software provided by Creative.
>
> When changing the Speaker selection (2.1/4.1/5.1), data is sent over usb to the device.
> However, when I try to change the settings for the X-Fi Crystalizer or EAX or CMSS-3D or Graphic Equalizer
> nothing gets sent to the device but the audio output does change and I am able to hear the corresponding effects.
>
> And as mentioned in my previous post, the lsusb output doesn't show any effect descriptors or feature units
>
> If this is in fact true that all the xtreme fidelity(X-Fi) stuff is happening in software alone, my purchase has been
> a total waste!! Does anybody on this list have a USB X-Fi 5.1 that they can use to verify my observations?

Yes, all the effects are done in software.  Even on many PCI cards
Creative implements the effects in the Windows driver.

Lee