From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: ALSA Driver for ARM Date: Wed, 30 Mar 2005 16:52:42 +0200 Message-ID: References: <42480A24.5070602@fetron.de> <4249C91C.9000000@t-online.de> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: <4249C91C.9000000@t-online.de> Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: T-Online Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Tue, 29 Mar 2005 23:31:08 +0200, T-Online wrote: > > Hi, > > I have a new hint, but the problem is not solved. > > > I want to programm an driver for the Cirrus CS42516 and the ARM9 CPU > > EP93xx also from Cirrus. > > > > I think, there are several errors: > > > > - when I start aplay, I receive a buffer. A dump to this memory region > > show only zeros. > > > I have written some characters into the DMA Memory Area (with a Hardware > Debugger) when the driver is started, but aplay is not started. After I > start aplay, all my characters are overwritten with Zero. > > Which function in ALSA is responsible for filling the DMA Buffer ? If it's not mmap mode, it must be through SNDRV_PCM_IOCTL_WRITEI_FRAMES ioctl (note that alsa-lib doesn't use write syscall). i.e. snd_pcm_lib_write() -> snd_pcm_lib_writei() -> snd_pcm_lib_write_transfer() -> copy_from_user() Takashi > > - after the complete buffer is transmitted (but not the complete > > file), I receive an underrun from ALSA > > > > - I never detect a mmap function call. > > > > > > Thanks, > > Klaus > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/alsa-devel > ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click