From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: Re: Usb audio - unsuported sampling rates Date: Tue, 10 Jul 2012 08:53:54 +0200 Message-ID: <4FFBD182.9040503@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bk0-f51.google.com (mail-bk0-f51.google.com [209.85.214.51]) by alsa0.perex.cz (Postfix) with ESMTP id 5F13924538 for ; Tue, 10 Jul 2012 08:53:58 +0200 (CEST) Received: by bkcjk13 with SMTP id jk13so3407177bkc.38 for ; Mon, 09 Jul 2012 23:53:58 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org Cc: gordon.dilan@gmail.com List-Id: alsa-devel@alsa-project.org Hi, On 10.07.2012 07:25, Gordon Dilan wrote: > I'm using an usb mic which(according to it's producer should support up to > 48kHz sampling rate). The problem is ALSA allows me to use only 16 kHz for > this device. I do not want to resample the data, I want to sample it at > 48kHz in order to be able to record some high pitch sounds 18-20kHz. > > I would want to try to do any modifications necessary in order to try > support 48kHz, but I'm not sure where to start. [...] > Some more information: > lsusb > Bus 001 Device 007: ID 1415:2000 Nam Tai E&E Products Ltd. or OmniVision > Technologies, Inc. Sony Playstation Eye > > lsusb -t Please also provide the output of 'lsusb -v'. > /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci_hcd/2p, 480M > |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/6p, 480M > |__ Port 2: Dev 7, If 0, Class=vend., Driver=ov534, 480M > |__ Port 2: Dev 7, If 1, Class=audio, Driver=snd-usb-audio, 480M > |__ Port 2: Dev 7, If 2, Class=audio, Driver=snd-usb-audio, 480M > > > At the moment I'm looking inside ALSA's source code to try to see from > where this limitation of 16000kHz for my device appears, but I have to > admit that I'm kind of lost. > Any pointers on what direction should I go to try make my desired rate > supported would be greatly appreciated! The device is queried for its supported sample rates during probe using class-specific commands. If it doesn't return all rates that are actually supported, we need to add a quirk and override this list. The list of known sample rates is included in /proc/asound/card1/stream0. What does that show for you? Daniel