- Alsa-devel - mailman.alsa-project.org

[alsa-devel] dmix does not mix small files??
by Prabhu Sivaraja 03 May '07

03 May '07

Hi, I've been stuck on this dmix problem for the past week and have tried everything under the sun. Please any help or comment is much appreciated. Thanks a lot. Background info. ----------------------- In my ALSA driver I have thread that keeps track of hw_ptr(dmix) appl_ptr(for all other cases) and copies the incoming data from kernal buffer into device circular buffer(which is monitored by the device). I allocate 64KB kernal buffer in my module_init function . (See allocation below) snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, snd_dma_continuous_data(GFP_KERNEL), 64*1024 , 64*1024); So I monitor this kernal buffer and copy data from this to my device circular buffer which is also 64KB. My period size is defined as 32KB. (See below) substream->runtime->hw.period_bytes_min = 1024*32; substream->runtime->hw.period_bytes_max = 1024*32; substream->runtime->hw.periods_min = 2; substream->runtime->hw.periods_max = 2; My asound.conf file pcm.mix { type dmix ipc_key 1024 slave { pcm "hw:0,0" rate 48000 } } pcm.!default { type plug slave.pcm "mix" } Everything was working fine until I noticed something weird. When I am playing a long wav file by invoking aplay and then try and play another small wav file simultaneously, the second file never gets mixed if the file is less than 64KB(my buffer size). If the second file is larger than 64KB then the second file gets mixed with the first one as it should since I am using dmix plugin. So in order to debug this I tried to decrease my period_size = 4KB but when I do this my hw_ptr never moves. My question. 1. Why do you think a file smaller than 64KB does not get mixed. (Obviously it has something to do with my buffer size but I dont get why?) 2. When I decrease my period_size to 4KB while keeping my buffer size at 64KB, why doesnt my hw_ptr move? 3. How else would I debug this? Thanks in advance. I would really appreciate any help. Regards Prabhu.

2 2

[alsa-devel] alsa test function?
by Ashlesha Shintre 03 May '07

03 May '07

Hi, Is there a test program for alsa, that gives a report on whether alsa is working correct with the underlying hardware or just does elementary testing of alsa on a system? Thanks, Ashlesha.

1 0

[alsa-devel] 1.0.14rc4 release
by Jaroslav Kysela 03 May '07

03 May '07

Hello all, 1.0.14rc4 packages are available for download on http://www.alsa-project.org . The full changelog can be obtained here: http://www.alsa-project.org/changes/v1-0-14rc3--v1-0-14rc4.txt . Jaroslav ----- Jaroslav Kysela <perex(a)suse.cz> Linux Kernel Sound Maintainer ALSA Project, SUSE Labs

1 0

[alsa-devel] Add support for new HP DV series laptops
by Tobin Davis 03 May '07

03 May '07

This patch adds support for 3 new HP laptops to the Conexant "Venice" driver. Signed off by Tobin Davis <tdavis(a)dsl-only.net>

2 1

[alsa-devel] ALSA TImers
by Nobin Mathew 03 May '07

03 May '07

Hi, I am new to ALSA. Can any body explain me the use of timers in ALSA, timers like the one in pcm_timer.c Thanks in advance Nobin Mathew

2 1

Re: [alsa-devel] Support for SAM9407?
by Ash Willis 03 May '07

03 May '07

Hi Pieter, > Are you interested in joining the FFADO project? (short into: FFADO = > new FreeBoB = drivers for FireWire Audio Interfaces / www.ffado.org). > I have absolutely zero experience in firewire audio and firewire in general to be honest, but the project does sound interesting. > To be frank/direct here, I think that ALSA is better 'completed' with > FFADO support than with driver support for obsolete cards. But of course > I'm a little biased here :). Be as Frank as you want, I totally agree with you :) The thing is, I have limited time and experience (I have written one ALSA driver). Although supporting older hardware doesn't bring a whole lot to the project, it does provide me with a training ground so I can be of greater use in the future. I can work at my own pace on an area that nobody else will be working on. I can improve my skills without stepping on other people's toes. Your project sounds interesting but I don't feel I have the knowledge to keep up on a project like this. This is why I'm messing around with this stuff, so that I can do some 'real work' some day soon ;) regards, Ash =

2 1

[alsa-devel] alsa driver api
by Michel Benoit 03 May '07

03 May '07

Hi Does anyone have some code examples that show how to send pcm samples directly to an alsa driver. I'm (still) having trouble building/using alsa-lib and I want to make sure that my driver works correctly. If I understand correctly it is possible to send sound samples using the alsa driver api only (no alsa-lib). All I want to do for now is send a fixed sine wave to the driver. I saw some code snippets that seemed to do just that in a recent email on this list but it would help a lot if I could have a look at the complete application. Thanks, Michel

2 1

[alsa-devel] Newb wants to fix snd_cs46xx driver
by chris＠idlelion.net 03 May '07

03 May '07

There's been a bug on this chip's driver for at least four years. https://bugtrack.alsa-project.org/alsa-bug/view.php?id=305 There are two ThinkPad 600X's in my home that have the problem. The chip is also in the ThinkPad A20m, A20p, A21m, A21p, A22m, A22p, T20, T21 and T22... and probably other brands as well. In the 600X, it happens to be paired with a CS4297A... hey, should I just try to get Linux to use that? (I use Fedora BTW.) How would I try to do that? Or... better still... how would I get either the '97A driver installed automatically by soundcard detection, or failing that, actually fix the driver? (I am a software developer who has written machine code for fun.) Thanks, Chris

1 0

[alsa-devel] Support for SAM9407?
by Ash Willis 02 May '07

02 May '07

Hi, I've just been digging around for information on the old Dream SAM9407 chip. What's the current support status in ALSA for this chip? I know some work was done on producing drivers for cards based on this chip and I know there were plans to port the efforts to ALSA. Did that ever happen? It doesn't seem so. Was there a specific reason why it wasn't ported in the end? In the interest of making ALSA that bit more complete as well as trying to improve my skills, I've been looking around for some older hardware that I can write drivers for. This chip seems like a good candidate considering the cards haven't quite disappeared into oblivion :) I was looking into the possiblity of porting the remaining kernel OSS drivers to ALSA...but I can't even find any test hardware because they're so rare. Ash Willis =

3 2

Re: [alsa-devel] alsa driver api
by Ciaccia 02 May '07

02 May '07

Hi Michel, Maybe you are referring to my post. I always use alsa-lib to send data to the driver, I think it is the easiest way and preferred way. Months ago I wanted to do the same (i.e. send data to the alsa-driver without alsa-lib) but then I understood this was not the right way. I'm not saying you cannot or should not try that, but from my experience (I spent a lot of time) it's not going to work. The problem I had was that my system did not support shared objects, nor -ldl, so I could not user the "standard" alsa-lib (which usually require pthread, dl, an *.so). Then Takashi gave me a patch for that, and now I'm an happy "static" alsa-lib user. Maybe one of the gurus (Takashi?) will give you some tips, but I think you really need a good reason for that. Good luck, sorry for not helping you Andrea ----- Original Message ---- From: Michel Benoit <murpme(a)gmail.com> To: ciacciax(a)yahoo.com; alsa-devel(a)alsa-project.org Sent: Wednesday, May 2, 2007 7:40:29 PM Subject: alsa driver api Hi Does anyone have some code examples that show how to send pcm samples directly to an alsa driver. I'm (still) having trouble building/using alsa-lib and I want to make sure that my driver works correctly. If I understand correctly it is possible to send sound samples using the alsa driver api only (no alsa-lib). All I want to do for now is send a fixed sine wave to the driver. I saw some code snippets that seemed to do just that in a recent email on this list but it would help a lot if I could have a look at the complete application. Thanks, Michel __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

1 0