Re: USB Audio libusb [Development (General)]

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DizzyOfCRN

Re: USB Audio libusb

#12

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If I recall it correctly or at firts place even understood it correctly, then there seems to be 2 types of isoc transfers that can be used by Poseidon. One is just the normal isoc transfer and the other is realtime implementation of isoc transfer. Don't know for sure what the difference is. Setting up the isoc transfer pipe might differ on those two and the driver code might be different.

For isoc transfer there needs to be a scheduler that makes sure no isoc transfers are dropped and that they happen at the right time. It all goes difficult as the device making use of the isoc transfer may be at any point on the device tree. One needs to calculate the usb bandwidth etc. and base the scheduler on that and other factors.

Poseidon controls the driver and device tree and it provides an API to communicate with the usb devices. Poseidon really doesn't care much about what sort of transfer pipe is opened or used, it only provides the means to do so and forwards the iorequests to the correct driver. Poseidon code is the higher level code for usb communication and drivers are ofcourse the lower level one.

Posted on: 2018/3/17 17:48

ncafferkey

Re: USB Audio libusb

#11

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Quote:

wawa wrote:
Quote:

ncafferkey wrote:
[quote]although I'm not sure if any of those solutions already have a driver with isochronous support.

does aros poseidon implement that? if not amiga doesnt have it as well, but if implemented at least aros68k might take advantage of it.

I read a long time ago that one of the non-PCI m68k USB interfaces had it (maybe the Subway), so I assume Poseidon supports it, and Dizzy seems to confirm that.

Posted on: 2018/3/17 16:58

DizzyOfCRN

Re: USB Audio libusb

#10

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Quote:

nikolaos wrote:
As we can use usb to get connected to internet it would also be cool for connection to usb audio devices to get sound.

A cross-platform library that gives apps easy access to USB devices.
Synchronous API and iso transfer with libusb 1.0

From what I understand iso transfers is what we need to make that work. How hard would it be to get this working with AROS.

https://sourceforge.net/p/libusb/mailman/message/22765031/

If someone interested maybe could come up with some price for the work to do it?

Libusb is just a wrapper to allow userland programs on Linux to communicate with the kernel usb. Libusb provides similar API as Poseidon.

There is already a hosted libusb driver for Aros. It was ment to ease usb native development for Aros. Much easier to debug on hosted than on native Aros system.

Aros only needs drivers with isoc transfers. I at some point enabled the isoc transfers on the hosted libusb driver, but I couldn't find anything to test it so it has been disabled on the driver.

Posted on: 2018/3/17 15:49

wawa

Re: USB Audio libusb

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Quote:

ncafferkey wrote:
Not OS4 people.

whoever runs "os4 classic" can use (and is well advised) poseidon usb stack instead of default syrion afair.

Quote:

OS3 people with PCI bridgeboards could potentially have a use for it

there are a number of amiga usb expansions with poseidon driver that dont rely on pci. the problem is that aros poseidon api has been extended (some field in some structure ive been told) so that aros usb device compiled for m68k might not work on genuine amiga out of the box. however people tested aros68k poseidon working with their expansions on amiga, i still would have to confirm this.
otherwise it shouldnt be a major issue to ifdef the incompatibility for m68k target, once its located.

Quote:

although I'm not sure if any of those solutions already have a driver with isochronous support.

does aros poseidon implement that? if not amiga doesnt have it as well, but if implemented at least aros68k might take advantage of it.

Posted on: 2018/3/17 10:56

ncafferkey

Re: USB Audio libusb

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Quote:

nikolaos wrote:

You think Amiga people might have use for this to or will it only work with Poseidon, Trident?

Not OS4 people. OS3 people with PCI bridgeboards could potentially have a use for it, although I'm not sure if any of those solutions already have a driver with isochronous support.

Posted on: 2018/3/16 19:01

sabbate

Re: USB Audio libusb

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I would say excellent, thank you :)

Posted on: 2018/3/14 16:34

https://www.actionaid.org/
https://www.jamendo.com/artist/511270/salvatore-abbate

nikolaos

Re: USB Audio libusb

Home away from home

Ntromans: Exactly :)

Neil: That is great news :) We talk in 3 months and you name a price and I will collect.

You think Amiga people might have use for this to or will it only work with Poseidon, Trident?

Posted on: 2018/3/13 22:51

www.aspireos.com

ntromans

Re: USB Audio libusb

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Quote:

ncafferkey wrote:
Ask me again in two or three months time. I'm planning to do some work on USB, so I might be able to fit that in.

That would be fantastic. I've always though one of the biggest issues with running AROS on a laptop has been the challenge of finding a supported audio chipset; having USB audio to fall back on would rmake a real difference there.

Cheers,
Nigel.

Posted on: 2018/3/13 18:07