2009-01-08 06:18:53     Audio IO error Issue on BF527

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2009-01-08 06:18:53     Audio IO error Issue on BF527

Vasanth Nayak (INDIA)

Message: 67622   


Hi All,


           Iam trying to get the audio up and running on the BF527 EZkit.Am using 2008R1.5 toolchain and kernel.


I have set the switches related to audio with the following configuration



SW4 - OFF ON OFF OFF (MIC Gain Switch )



SW8 - ON OFF OFF ON  (Mic/HP LPBK Audio Mode switch)



SW17 -  ON ON (SPORT0A ENBL switch)



SW19 - OFF ON OFF ON (SPI/TWI switch)

SW20 - ON ON ON ON (SPORT0A ENBL switch)


And i get this in the boot-time message


i2c-bfin-twi i2c-bfin-twi.0: Blackfin BF5xx on-chip I2C TWI Contoller Driver, Version 1.8, regs_base@ffc01400

Advancmd Linux Sound Architecture Driver Version 1.0.12rc1 (Thu$Jun 22 13:55:50 2006 UTC).

ASoC version 0.13.1

dma rx:3 tx:4, err irq:15, regs:ffc00800

ssm2602 Audio Codec 0.1<6>dma_alloc_init: dma_page @ 0x00657000 - 256 pages at 0x01f00000

asoc: SSM2602 <-> bf5xx-i2s-0 mapping ok

ALSA device list:

  #0: bf5xx_ssm2602 (SSM2602)


But when i run tone function, i get this error (errno = 5 stands for IO error i think


root:~> tone -r

TONE: generating ramp wave at 1000 Hz...

ERROR: write(/dev/dsp) failed, errno=5


Any ideas what could be wrong. ?


One more question is


1) How would i change the volume programatically ? Do i use /dev/mixer ? where can i find the doc on ioctl's or any other info on mixer ?





2009-01-09 04:18:01     Re: Audio IO error Issue on BF527

Cliff Cai (CHINA)

Message: 67691   


1.I followed your settings and it worked for me.Would you please check  if the switchs are pushed to the  correct position?


2.You can refer to .../uclinux-dist/user/vplay/mixer.c for oss-based controls or ../uclinux-dist/user/blkfin-apps/alsa-utils/amixer


/amixer.c for alsa-based controls.








2009-01-09 07:50:21     Re: Audio IO error Issue on BF527

Vasanth Nayak (INDIA)

Message: 67716   


Hi Cai,


                  Found the issue. It was actually the issue with the I2C address (selectable between 0x1a and 0x1b during kernel configuration). I had to change the i2c address to 0x1b to make it work.




Thanks for the help on the mixer side. will look into the vplay source.