From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from metis.extern.pengutronix.de (metis.extern.pengutronix.de [83.236.181.26]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id ABE82DE14D for ; Tue, 15 Apr 2008 18:23:33 +1000 (EST) Received: from themisto.extern.pengutronix.de ([83.236.181.29] helo=localhost) by metis.extern.pengutronix.de with esmtp (Exim 4.63) (envelope-from ) id 1Jlg8M-00045a-Lo for linuxppc-dev@ozlabs.org; Tue, 15 Apr 2008 10:03:24 +0200 From: Juergen Beisert To: linuxppc-dev@ozlabs.org Date: Tue, 15 Apr 2008 10:03:17 +0200 References: <47FDEF9B.5000506@semihalf.com> <47FF135E.2060003@246tnt.com> In-Reply-To: <47FF135E.2060003@246tnt.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-Id: <200804151003.17865.jbe@pengutronix.de> Subject: Re: State of the MPC5200 PSC AC97 driver List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Friday 11 April 2008 09:29, Sylvain Munaut wrote: > > Last year you have posted a MPC5200 PSC AC97 driver patch > > "[PATCH 9/9] sound: Add support for Freescale MPC5200 AC97 interface." > > > > with the following comment: > >> Not quite a clean driver, but it get things done (well, mostly). > >> Only included to be able to test functionalityi/usage of > >> the BestComm driver. > > Yes ... and it still applies. > > > There are various FIXMEs and commented out code here and there. > > Could you elaborate a bit on the overall state of the driver's > > functionality, > > which areas need improvement and attention? > > It's a minimum boiler plate. > I filled the function at the minimum to get some sound output and being > able to hear music coming out of it :) > I also completely skipped the 5200 (not B) support ... > > At first there was no DMA at all (full software copy). I added some > simple DMA later just to prove it could work and how to use the API. > > I just wrote it to get some sound, prove the interface could work under > linux and to show how to use DMA. I had hoped someone else would finish > it ... (yeah, I know ... big mistake). > > > Seems that you mainly tested BestComm with this driver, what was the > > overall > > BestComm performance, any issues here? Did you use any specific test > > setup involving some dedicated application, etc.? > > My test was listening to Gorrillaz "Feel Good inc" using mplayer ... > > > Did anyone else tried it and/or has a updated version or can share > > experience? > > At the time several other people tried it and it worked ... unless you > did lots of harddrive IO and then it crumbled ... Currently it fails to play anything with an external Wolfson WM9712 connect= ed=20 to it. It seems the current AC97 reset sequence switches the WM9712 into=20 testmode due to SDATA_OUT and Sync are not held low while the reset is=20 active. Any idea to solve this? Switching both signals to GPIO and force th= em=20 to low level while reset is active? How to cover PSC1 and PSC2 with differe= nt=20 GPIOs for this case? Juergen =2D-=20 Dipl.-Ing. Juergen Beisert | http://www.pengutronix.de =A0Pengutronix - Linux Solutions for Science and Industry =A0 Handelsregister: Amtsgericht Hildesheim, HRA 2686 =A0 =A0 =A0 Vertretung Sued/Muenchen, Germany Phone: +49-8766-939 228 | Fax: +49-5121-206917-9