From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [RFC] ASoC: sgtl5000: Remove cache support Date: Sun, 5 May 2013 11:15:15 +0100 Message-ID: <20130505101515.GT4945@sirena.org.uk> References: <1367610549-25542-1-git-send-email-festevam@gmail.com> <20130503223613.GR4945@sirena.org.uk> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============2704569826442262808==" Return-path: Received: from cassiel.sirena.org.uk (cassiel.sirena.org.uk [80.68.93.111]) by alsa0.perex.cz (Postfix) with ESMTP id B5472261A55 for ; Sun, 5 May 2013 12:15:34 +0200 (CEST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Fabio Estevam Cc: Fabio Estevam , alsa-devel@alsa-project.org, matt@genesi-usa.com, eric.nelson@boundarydevices.com, troy.kisky@boundarydevices.com, zengzm.kernel@gmail.com List-Id: alsa-devel@alsa-project.org --===============2704569826442262808== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="vru7fAags9pVPvn5" Content-Disposition: inline --vru7fAags9pVPvn5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Sat, May 04, 2013 at 05:25:45PM -0300, Fabio Estevam wrote: > I see this commit from Freescale kernel that workarounds exactly the same issue: > http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/commit/sound/soc/codecs/sgtl5000.c?h=imx_3.0.35_1.1.0&id=2f7d47e760725d33f6b2eb01024b800d64ff8944 > It seems that caching is broking with this codec. This is nonsensical. Clearly there's something about the use of the cache that is interacting poorly with the device but we've no idea what it is. Simply having a copy of the register map in the host memory is not going to do anything to the device, there must be some other issue at work. > If this is true, should we go with the proposal of this RFC patch? We should understand what the issue is. Looking at the commit above it's not removing the cache at all, it's both attempting to work around an issue with the cache not handling the register step size properly (this looks like it's just a bug in the current driver) and reordering some of the startup around the regulator (the comment says it's open coding cache_bypass but it's also moving blocks of code around). --vru7fAags9pVPvn5 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iQIcBAEBAgAGBQJRhjEqAAoJELSic+t+oim92CgP/3lfIzxJLzWM7vBVtOH2YGv6 k9szePKV+0D0ZpEzqd1mZVJo204s8tYX7UykIuZJ8iTzwMuXUCO9nYohu84Xd2F+ daHtS9p+Ip7JtG9oX47IcDGGUN5ZPAWrayvCRwxr/xW99zw6Odae2izfTZkNqTx6 lKyVA1eT9XR9dzh5xsV8F8LYUMZMlbHDXDs2sEWcwYLTosZYdso5gpPpcjcgJSxq 8dOnyeOEJQcWJvS8PRFrxw4hBqTOwk4/F32nN46qIDWuDfGe60a1wITp3xMxDqwK nlUvFaFZQGh1sVD/ikEDgWu5v2IuoPs1pz6vOfUvOEbD2Atj/BsiuEKggQeESyJc JWLWH3sqEKwmHoPD5ORF3sSr+Kk8xCo5UBMaEOL8Yf6u7PHCDrdO3uZZg9et7R2f aCa36L4KH1nFsIQzWuMFVElKaTu9I9w4xHUCPfOPWhks/FTfknyiGEdz71qdI2lH Z7ggJB8Ex8NVP5S6R1HGrkxFDFeNbCn1xMkeEi3xB1yEDstxdb9t934qOJpa/V0S 2QUQzMj5HnJtKm2uU3qQpUYtLentePVm+noZVfUmijogkPUubTVvzrxA0XYOMBym FZ2Ra+0nO8OXc/CYC6yvabwSjk+HIvbKAwQNv7gM5/9HV8D2rDkpxb9yZ2x9K+79 /GL1HFNCqhjqqeQmco8K =eIvL -----END PGP SIGNATURE----- --vru7fAags9pVPvn5-- --===============2704569826442262808== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============2704569826442262808==--