From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Andrey Liakhovets" Subject: Re: [Openchrome-users] via epia boards sound quality Date: Sun, 20 Aug 2006 12:02:39 +0400 Message-ID: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="_===171768144====cgp.dol.ru===_" Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@lists.sourceforge.net Errors-To: alsa-devel-bounces@lists.sourceforge.net To: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org This is a multi-part MIME message --_===171768144====cgp.dol.ru===_ Content-Type: text/plain; charset="KOI8-R" Content-Transfer-Encoding: quoted-printable James Courtier-Dutton wrote: > Andrey Liakhovets wrote: >> >> In short, the attached 1-line patch against alsa 1.0.11 solves the pro= blem >> >> If necessary, I can give more details or upload them on our ftp. >> >> Andrey Liakhovets > > > Would you be able to provide 2 things? > > 1) Please add a "Signed-off-by:" entry. > 2) Do you have the VT1616A datasheet? > > I can find the VT1616 datasheet online, but not the VT1616A. > > James No, I have only the VT1616 datasheet. Below I repeat the references, info and patch with my Signed-off-by. http://wiki.openchrome.org/pipermail/openchrome-users/2006-May/001193.htm= l http://wiki.openchrome.org/pipermail/openchrome-users/2006-May/001199.htm= l http://wiki.openchrome.org/pipermail/openchrome-users/2006-May/001247.htm= l http://wiki.openchrome.org/pipermail/openchrome-users/2006-July/001456.ht= ml 1) in our lab, we failed in getting bad sound on a running system, despite a long and intensive heating; 2) we have succeded in reproducing the problem at the system start (with = a probability of about 2/3) with a pre-cooled sound codec chip; 3) we have succeded in reproducing the problem on the system running Linu= x by cutting analog power supply from the codec, cooling the codec = and reattaching analog power; 4) on wire, the problem looks like undervoltage of codec analog power (2V or less instead of 5V): meanwhile the codec tries to consume about 200mA (instead of <40mA), and the voltage regulator chip be= gins (from 100mA) reducing the voltage; 5) analysis of the situation with WinXP shows that the WinXP sound driver= loading brings the codec analog voltage (and sound) to norm, and this sta= te is tolerant to actions described under (3); 6) analysis of the WinXP sound driver loading allowed us to detect that v= ery bit, the set of which normalizes the codec's analog power consumption; 7) a check with Linux has confirmed this. The attached 1-line patch against alsa 1.0.11 solves the problem (for our VIA EPIA SP8000). Signed-off-by: Andrey Liakhovets --_===171768144====cgp.dol.ru===_ Content-Type: application/octet-stream Content-Disposition: attachment; filename="alsa-kernel-1.0.11-rover-ac97-vt1617a.patch" Content-Transfer-Encoding: base64 ZGlmZiAtTmF1ciBhL3BjaS9hYzk3L2FjOTdfcGF0Y2guYyBiL3BjaS9hYzk3L2FjOTdfcGF0 Y2guYwotLS0gYS9wY2kvYWM5Ny9hYzk3X3BhdGNoLmMJMjAwNi0wNC0xMiAwMDo0Njo0NyAr MDQwMAorKysgYi9wY2kvYWM5Ny9hYzk3X3BhdGNoLmMJMjAwNi0wNy0yNiAxMDoxNTo1OCAr MDQwMApAQCAtMjc0Miw2ICsyNzQyLDcgQEAKICAqLwogaW50IHBhdGNoX3Z0MTYxN2Eoc3Ry dWN0IHNuZF9hYzk3ICogYWM5NykKIHsKKwlzbmRfYWM5N193cml0ZV9jYWNoZShhYzk3LCAw eDVjLCAweDIwKTsJLyogYnJpbmcgYW5hbG9nIHBvd2VyIGNvbnN1bXB0aW9uIHRvIG5vcm1h bCwgbGlrZSBXaW5YUCBkcml2ZXIgZm9yIEVQSUEgU1AgKi8KIAlhYzk3LT5leHRfaWQgfD0g QUM5N19FSV9TUERJRjsJLyogZm9yY2UgdGhlIGRldGVjdGlvbiBvZiBzcGRpZiAqLwogCWFj OTctPnJhdGVzW0FDOTdfUkFURVNfU1BESUZdID0gU05EUlZfUENNX1JBVEVfNDQxMDAgfCBT TkRSVl9QQ01fUkFURV80ODAwMDsKIAlyZXR1cm4gMDsK --_===171768144====cgp.dol.ru===_ Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 --_===171768144====cgp.dol.ru===_ Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Alsa-devel mailing list Alsa-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/alsa-devel --_===171768144====cgp.dol.ru===_--