From owner-freebsd-questions@freebsd.org Sat Jul 25 03:37:48 2015 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id AC8D99AA7BA for ; Sat, 25 Jul 2015 03:37:48 +0000 (UTC) (envelope-from ps06756@gmail.com) Received: from mail-lb0-x230.google.com (mail-lb0-x230.google.com [IPv6:2a00:1450:4010:c04::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3869D166E for ; Sat, 25 Jul 2015 03:37:48 +0000 (UTC) (envelope-from ps06756@gmail.com) Received: by lbbzr7 with SMTP id zr7so25358513lbb.1 for ; Fri, 24 Jul 2015 20:37:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to:content-type; bh=eLU/HAi5tDKsWdG5B1106PCFn3MU6+ZslI2w8Sh/qRM=; b=MwIL9OPw2i7l25mw/S698h9/HZZgYnRF8c2Q5P0qEOJ4m2G60F0BCPZWjWBL+k0Ods Rc6Ou24FdM7902whWgpRsMiJTTYGqccyziPRK5FOj5HysF0dYFChp+ju0/vWgk2B4FHM LHOnNdIft08BSpKDmkTk8GPQsWciGcuP65ye90GAeg08Vxv1/NJQ7OTerckt+3DQi/Ml MzoY837Ma0b0Vdt3ZY47Re6M96/kwYfNkWI+KoqzwhAFNdd2jQCZuNLKy890IgTtmoos /c1Fz2eJukZDP6arxMX8hPISMMwu0K/ewe5FJLrD44nsD+4gN+HwiiYcdL7E9eZl6m1g Di1g== X-Received: by 10.152.5.36 with SMTP id p4mr3656359lap.102.1437795465998; Fri, 24 Jul 2015 20:37:45 -0700 (PDT) MIME-Version: 1.0 Received: by 10.25.87.194 with HTTP; Fri, 24 Jul 2015 20:37:26 -0700 (PDT) From: Pratik Singhal Date: Sat, 25 Jul 2015 09:07:26 +0530 Message-ID: Subject: FreeBSD Ac97 interface To: FreeBSD Questions Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 25 Jul 2015 03:37:48 -0000 Hello all, I am writing the driver for AC'97 controller present in Allwinner A10 SoC as a part of my Google summer of code Project. I have understood the theoretical aspects of AC'97 and know "what" to code, but I am unable to understand , how to interface the code with FreeBSD kernel. For ex, when making changes in the mmc driver, it was very clear that the high-level file sys/dev/mmc/mmc.c will call the methods defined in our implementation of mmc driver, In the case of AC'97, what all files should I look at ? I have so far looked at sys/dev/sound/pcm/ directory, but can't seem to understand much there. Also,how does FreeBSD control the AC-link , which will be used to control various parameters related to AC'97 codec I/O ? I am new to working with sound at this low level, so there might be some trivial things which I may have missed. Any help would be very valuable for timely completion of project. Thanks, Pratik Singhal