From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932121AbWCJDWu (ORCPT ); Thu, 9 Mar 2006 22:22:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932133AbWCJDWu (ORCPT ); Thu, 9 Mar 2006 22:22:50 -0500 Received: from mustang.oldcity.dca.net ([216.158.38.3]:36587 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S932121AbWCJDWu (ORCPT ); Thu, 9 Mar 2006 22:22:50 -0500 Subject: Re: How can I link the kernel with libgcc ? From: Lee Revell To: Carlos Munoz Cc: Valdis.Kletnieks@vt.edu, linux-kernel@vger.kernel.org, alsa-devel In-Reply-To: <4410EC0D.3090303@kenati.com> References: <4410D9F0.6010707@kenati.com> <200603100145.k2A1jMem005323@turing-police.cc.vt.edu> <1141956362.13319.105.camel@mindpipe> <4410EC0D.3090303@kenati.com> Content-Type: text/plain Date: Thu, 09 Mar 2006 22:22:41 -0500 Message-Id: <1141960963.13319.116.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.5.92 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org (added alsa-devel to cc:) On Thu, 2006-03-09 at 19:01 -0800, Carlos Munoz wrote: > >Audio drivers should never have to directly manipulate the samples - > >they just manage the DMA buffers and interrupts and wake up the process > >at the right time. Mixing, routing, volume control, DSP go in > >userspace. > > Unfortunately, the driver needs to populate several coefficient tables > for the hardware to perform silence suppression and other advance > features. The values for these tables are calculated using log10 > operations. I don't see a clean way to push these operations to user > space without the need for custom applications that build the tables and > pass them to the driver. Unless you can do it with fixed point math, or use a static table, you might have to do just that, with a sysfs interface. For example the emu10k1 driver uses an ioctl interface to upload code to the built in (floating point) DSP. But new ioctls are frowned upon... Lee