2009-06-24 08:55:22     alsa mmap doesn't work in 2008R1.5 on bf527

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2009-06-24 08:55:22     alsa mmap doesn't work in 2008R1.5 on bf527

Stefan Wanja (GERMANY)

Message: 76239   

 

Hello,

 

 

 

I am trying to use the ssm2602 codec on the bf527 ezKit with mmap. I have configured it in the kernel and it builds fine. After starting I try arecord --mmap which fails with this output:

 

root:/usr/share/alsa/cards> arecord --mmap

Recording WAVE 'stdin' : Unsigned 8 bit, Rate 8000 Hz, Mono

ALSA lib ../../../alsa-lib-1.0.12/src/pcm/pcm_mmap.c:370:(snd_pcm_mmap) mmap failed: No such device

arecord: set_params:965: Unable to install hw params:

ACCESS:  MMAP_INTERLEAVED

FORMAT:  U8

SUBFORMAT:  STD

SAMPLE_BITS: 8

FRAME_BITS: 8

CHANNELS: 1

RATE: 8000

PERIOD_TIME: (85312 85313)

PERIOD_SIZE: (682 683)

PERIOD_BYTES: (682 683)

PERIODS: (3 5)

BUFFER_TIME: 341250

BUFFER_SIZE: 2730

BUFFER_BYTES: 2730

TICK_TIME: 4000

root:/usr/share/alsa/cards>

 

 

With strace I see the following:

 

open("/dev/aloadC30", O_RDONLY)         = -1 ENOENT (No such file or directory)

open("/dev/snd/controlC31", O_RDONLY)   = -1 ENOENT (No such file or directory)

open("/dev/aloadC31", O_RDONLY)         = -1 ENOENT (No such file or directory)

open("/dev/snd/controlC0", O_RDONLY)    = 3

close(3)                                = 0

stat("/usr/share/alsa/alsa.conf", {st_mode=S_IFREG|0644, st_size=7701, ...}) = 0

open("/dev/snd/controlC0", O_RDONLY)    = 3

close(3)                                = 0

open("/dev/snd/controlC0", O_RDWR)      = 3

ioctl(3, USBDEVFS_CONTROL, 0x65f4d4)    = 0

ioctl(3, UI_DEV_CREATE, 0x65f49c)       = 0

close(3)                                = 0

open("/dev/snd/controlC0", O_RDWR)      = 3

ioctl(3, USBDEVFS_CONTROL, 0x65f7ec)    = 0

ioctl(3, 0x40045532, 0x65f814)          = 0

open("/dev/snd/pcmC0D0c", O_RDWR|O_NONBLOCK) = 4

close(3)                                = 0

ioctl(4, AGPIOC_ACQUIRE or APM_IOC_STANDBY, 0x65f640) = 0

fcntl(4, F_GETFL)                       = 0x802 (flags O_RDWR|O_NONBLOCK)

ioctl(4, AGPIOC_INFO, 0x65f7ec)         = 0

ioctl(4, AGPIOC_RELEASE or APM_IOC_SUSPEND, 0x65f7e4) = 0

mmap2(NULL, 4096, PROT_READ, MAP_SHARED, 4, 0xfff80000) = -1 ENODEV (No such device)

ioctl(4, 0xc0844123, 0x65f760)          = 0

fcntl(4, F_GETFL)                       = 0x802 (flags O_RDWR|O_NONBLOCK)

fcntl(4, F_SETFL, O_RDWR)               = 0

ioctl(4, AGPIOC_ACQUIRE or APM_IOC_STANDBY, 0x65fc60) = 0

rt_sigaction(SIGINT, {0x3bfcc88, [INT], SA_RESTART}, {SIG_DFL}, 8) = 0

rt_sigaction(SIGTERM, {0x3bfcc88, [TERM], SA_RESTART}, {SIG_DFL}, 8) = 0

rt_sigaction(SIGABRT, {0x3bfcc88, [ABRT], SA_RESTART}, {SIG_DFL}, 8) = 0

write(2, "Recording", 9Recording)                = 9

write(2, " ", 1 )                        = 1

write(2, "WAVE", 4WAVE)                     = 4

write(2, " \'", 2 ')                      = 2

write(2, "stdin", 5stdin)                    = 5

write(2, "\' : ", 4' : )                    = 4

write(2, "Unsigned 8 bit", 14Unsigned 8 bit)          = 14

write(2, ", ", 2, )                       = 2

write(2, "Rate ", 5Rate )                    = 5

write(2, "8000", 48000)                     = 4

write(2, " Hz, ", 5 Hz, )                    = 5

write(2, "Mono", 4Mono)                     = 4

write(2, "\n", 1)                       = 1

ioctl(4, 0xc25c4110, 0x65d5a8)          = 0

ioctl(4, 0xc25c4110, 0x65d5a8)          = 0

ioctl(4, 0xc25c4110, 0x65d5a8)          = 0

ioctl(4, 0xc25c4110, 0x65d2e4)          = 0

ioctl(4, 0xc25c4110, 0x65d2e4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65d2d4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65d028)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65cdd4)          = 0

ioctl(4, 0xc25c4110, 0x65d4cc)          = 0

ioctl(4, 0xc25c4110, 0x65d4cc)          = 0

ioctl(4, 0xc25c4110, 0x65d490)          = 0

ioctl(4, 0xc25c4110, 0x65d490)          = 0

ioctl(4, 0xc25c4110, 0x65d4bc)          = 0

ioctl(4, 0xc25c4110, 0x65ceb8)          = 0

ioctl(4, 0xc25c4110, 0x65ceb8)          = 0

ioctl(4, 0xc25c4110, 0x65ce08)          = 0

ioctl(4, 0xc25c4110, 0x65ce08)          = 0

ioctl(4, 0xc25c4110, 0x65cdcc)          = 0

ioctl(4, 0xc25c4110, 0x65cdf0)          = 0

ioctl(4, 0xc25c4111, 0x65cdf0)          = 0

ioctl(4, 0xc0844123, 0x67dc74)          = 0

ioctl(4, 0xc0684113, 0x65cd60)          = 0

ioctl(4, 0x80104132, 0x65ccb4)          = 0

ioctl(4, 0x80104132, 0x65ccb4)          = 0

write(2, "ALSA lib ", 9ALSA lib )                = 9

write(2, "../../../alsa-lib-1.0.12/src/pcm"..., 43../../../alsa-lib-1.0.12/src/pcm/pcm_mmap.c) = 43

write(2, ":", 1:)                        = 1

write(2, "370", 3370)                      = 3

write(2, ":(", 2:()                       = 2

write(2, "snd_pcm_mmap", 12snd_pcm_mmap)            = 12

write(2, ") ", 2) )                       = 2

write(2, "mmap failed", 11mmap failed)             = 11

write(2, ": ", 2: )                       = 2

write(2, "No such device", 14No such device)          = 14

write(2, "\n", 1)                       = 1

...

_exit(1)                                = ?

Process 163 detached

root:/usr/share/alsa/cards> strace arecord --mmap

 

Mybootlog looks like that:

 

U-Boot 1.1.6 (ADI-2008R1.5) (Apr 14 2009 - 16:55:58)

 

CPU:   ADSP bf527-0.0 (Detected Rev: 0.0)

Board: ADI BF527 EZ-Kit board

       Support:   blackfin.uclinux.org/

Clock: VCO: 525 MHz, Core: 525 MHz, System: 131 MHz

RAM:   64 MB

Flash:  4 MB

In:    serial

Out:   serial

Err:   serial

Net:   Blackfin EMAC

MAC:   00:E0:22:FE:BC:04

Hit any key to stop autoboot:  0

## Booting image at 01000000 ...

   Image Name:   Linux-2.6.22.19-ADI-2008R1.5-svn

   Created:      2009-06-23  20:19:20 UTC

   Image Type:   Blackfin Linux Kernel Image (gzip compressed)

   Data Size:    976569 Bytes = 953.7 kB

   Load Address: 00001000

   Entry Point:  0019a000

   Verifying Checksum ... OK

   Uncompressing Kernel Image ... OK

Starting Kernel at = 19a000

Linux version 2.6.22.19-ADI-2008R1.5-svn6845 (user@debby) (gcc version 4.1.2 (ADI svn)) #30 Tue Jun 23 22:19:04 CEST 2009

early printk enabled on early_BFuart0

Hardware Trace Active and Enabled

Blackfin support (C) 2004-2007 Analog Devices, Inc.

Compiled for ADSP-BF527 Rev 0.0

Warning: Unsupported Chip Revision ADSP-BF527 Rev 0.0 detected

Blackfin Linux support by   blackfin.uclinux.org/

Processor Speed: 525 MHz core clock and 131 MHz System Clock

Board Memory: 64MB

Kernel Managed Memory: 64MB

Memory map:

  text      = 0x00001000-0x0012b8b0

  rodata    = 0x0012c000-0x00185328

  data      = 0x00186000-0x0019a000

    stack   = 0x00186000-0x00188000

  init      = 0x0019a000-0x001b4000

  bss       = 0x001b4000-0x001c3db0

  available = 0x001c3db0-0x03eff000

  DMA Zone  = 0x03f00000-0x04000000

NOMPU: setting up cplb tables for global access

Instruction Cache Enabled

Data Cache Enabled (write-through)

Built 1 zonelists.  Total pages: 16002

Kernel command line: root=/dev/mtdblock2 rw rootfstype=jffs2 earlyprintk=serial,uart1,57600 console=tty0 console=ttyBF0,57600

Configuring Blackfin Priority Driven Interrupts

PID hash table entries: 256 (order: 8, 1024 bytes)

console handover: boot [early_BFuart0] -> real [ttyBF0]

Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)

Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)

Memory available: 62124k/65536k RAM, (104k init code, 1194k kernel code, 505k data, 1024k dma, 584k reserved)

Blackfin Scratchpad data SRAM: 4 KB

Blackfin Data A SRAM: 16 KB (15 KB free)

Blackfin Data B SRAM: 16 KB (16 KB free)

Blackfin Instruction SRAM: 48 KB (40 KB free)

Security Framework v1.0.0 initialized

Mount-cache hash table entries: 512

NET: Registered protocol family 16

Blackfin GPIO Controller

Blackfin DMA Controller

stamp_init(): registering device resources

Generic PHY: Registered new driver

NET: Registered protocol family 2

IP route cache hash table entries: 1024 (order: 0, 4096 bytes)

TCP established hash table entries: 2048 (order: 2, 16384 bytes)

TCP bind hash table entries: 2048 (order: 1, 8192 bytes)

TCP: Hash tables configured (established 2048 bind 2048)

TCP reno registered

JFFS2 version 2.2. (NAND) © 2001-2006 Red Hat, Inc.

io scheduler noop registered

io scheduler anticipatory registered (default)

io scheduler cfq registered

bfin-otp: initialized

bfin-wdt: initialized: timeout=20 sec (nowayout=0)

Serial: Blackfin serial driver

bfin-uart.1: ttyBF0 at MMIO 0xffc02000 (irq = 31) is a BFIN-UART

RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize

bfin_mac_mdio: probed

bfin_mac: attached PHY driver [Generic PHY] (mii_bus:phy_addr=0:01, irq=-1, mdc_clk=2500000Hz(mdc_div=25)@sclk=131MHz)

bfin_mac: Version 1.1, Blackfin BF53[67] BF527 on-chip Ethernet MAC driver

physmap platform flash device: 00400000 at 20000000

physmap-flash.0: Found 1 x16 devices at 0x0 in 16-bit bank

Amd/Fujitsu Extended Query Table at 0x0040

number of CFI chips: 1

cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness.

RedBoot partition parsing not available

Using physmap partition information

Creating 3 MTD partitions on "physmap-flash.0":

0x00000000-0x00030000 : "Bootloader"

0x00030000-0x00130000 : "Kernel"

0x00130000-0x00400000 : "RootFS"

bfin-spi bfin-spi.0: Blackfin BF5xx on-chip SPI Contoller Driver, Version 1.0, regs_base@ffc00500, dma channel@7

rtc-bfin rtc-bfin: rtc core: registered rtc-bfin as rtc0

i2c /dev entries driver

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

Advanced 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 @ 0x03eb3000 - 256 pages at 0x03f00000

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

ALSA device list:

  #0: bf5xx_ssm2602 (SSM2602)

TCP cubic registered

NET: Registered protocol family 1

NET: Registered protocol family 17

rtc-bfin rtc-bfin: setting the system clock to 1970-01-01 04:40:19 (16819)

VFS: Mounted root (jffs2 filesystem).

Freeing unused kernel memory: 104k freed

                           _____________________________________

        a8888b.           / Welcome to the uClinux distribution \

       d888888b.         /       _     _                         \

       8P"YP"Y88        /       | |   |_|            __  __ (TM)  |

       8|o||o|88  _____/        | |    _ ____  _   _ \ \/ /       |

       8'    .88       \        | |   | |  _ \| | | | \  /        |

       8`._.' Y8.       \       | |__ | | | | | |_| | /  \        |

      d/      `8b.       \      \____||_|_| |_|\____|/_/\_\       |

     dP   .    Y8b.       \   For embedded processors including   |

    d8:'  "  `::88b        \    the Analog Devices Blackfin      /

   d8"         'Y88b        \___________________________________/

  :8P    '      :888

   8a.   :     _a88P         For further information, check out:

._/"Yaa_:   .| 88P|            -   blackfin.uclinux.org/

\    YP"    `| 8P  `.          -   docs.blackfin.uclinux.org/

/     \.___.d|    .'           -   www.uclinux.org/

`--..__)8888P`._.'  jgs/a:f    -   www.analog.com/blackfin

 

Have a lot of fun...

 

 

BusyBox v1.4.1 (2009-06-07 11:44:39 CEST) Built-in shell (msh)

Enter 'help' for a list of built-in commands.

 

My /dev looks like that:

 

 

root:/> ls -lisaR /dev

/dev:

     38    0 drwxr-xr-x    4 root     root            0 Jan  1 04:40 .

      1    0 drwxr-xr-x   15 root     root            0 Jan  1 00:00 ..

    317    0 crw-------    1 root     root       5,   1 Jan  1 04:40 console

    348    0 crw-rw----    1 root     root       1,   7 Jan  1 02:22 full

    343    0 crw-rw----    1 root     root      89,   0 Jan  1 02:22 i2c-0

    349    0 crw-rw----    1 root     root       1,   2 Jan  1 02:22 kmem

    345    0 crw-rw----    1 root     root       1,  11 Jan  1 02:22 kmsg

    373    0 srw-rw-rw-    1 root     root            0 Jan  1 04:40 log

    350    0 crw-rw----    1 root     root       1,   1 Jan  1 02:22 mem

    321    0 brw-rw----    1 root     root      31,   0 Jan  1 02:22 mtdblock0

    320    0 brw-rw----    1 root     root      31,   1 Jan  1 02:22 mtdblock1

    318    0 brw-rw----    1 root     root      31,   2 Jan  1 02:22 mtdblock2

    315    0 crw-rw-rw-    1 root     root       1,   3 Jun  7  2009 null

    344    0 crw-rw----    1 root     root     253,   0 Jan  1 02:22 otp

    354    0 crw-rw----    1 root     root       5,   2 Jan  1 02:22 ptmx

      1    0 drwxr-xr-x    2 root     root            0 Jan  1  2007 pts

    337    0 brw-rw----    1 root     root       1,   0 Jan  1 02:22 ram0

    336    0 brw-rw----    1 root     root       1,   1 Jan  1 02:22 ram1

    327    0 brw-rw----    1 root     root       1,  10 Jan  1 02:22 ram10

    326    0 brw-rw----    1 root     root       1,  11 Jan  1 02:22 ram11

    325    0 brw-rw----    1 root     root       1,  12 Jan  1 02:22 ram12

    324    0 brw-rw----    1 root     root       1,  13 Jan  1 02:22 ram13

    323    0 brw-rw----    1 root     root       1,  14 Jan  1 02:22 ram14

    322    0 brw-rw----    1 root     root       1,  15 Jan  1 02:22 ram15

    335    0 brw-rw----    1 root     root       1,   2 Jan  1 02:22 ram2

    334    0 brw-rw----    1 root     root       1,   3 Jan  1 02:22 ram3

    333    0 brw-rw----    1 root     root       1,   4 Jan  1 02:22 ram4

    332    0 brw-rw----    1 root     root       1,   5 Jan  1 02:22 ram5

    331    0 brw-rw----    1 root     root       1,   6 Jan  1 02:22 ram6

    330    0 brw-rw----    1 root     root       1,   7 Jan  1 02:22 ram7

    329    0 brw-rw----    1 root     root       1,   8 Jan  1 02:22 ram8

    328    0 brw-rw----    1 root     root       1,   9 Jan  1 02:22 ram9

    347    0 crw-rw----    1 root     root       1,   8 Jan  1 02:22 random

    319    0 lrwxrwxrwx    1 root     root            9 Jan  1 02:22 root -> mtdblock2

    351    0 crw-rw----    1 root     root     254,   0 Jan  1 02:22 rtc0

    338    0 drw-r--r--    2 root     root            0 Jan  1 02:22 snd

    355    0 crw-rw----    1 root     root       5,   0 Jan  1 02:22 tty

    353    0 crw-rw----    1 root     root     204,  64 Jan  1 02:22 ttyBF0

    346    0 crw-rw----    1 root     root       1,   9 Jan  1 02:22 urandom

    352    0 crw-rw----    1 root     root      10, 130 Jan  1 02:22 watchdog

    316    0 crw-rw-rw-    1 root     root       1,   5 Jun  7  2009 zero

 

/dev/pts:

      1    0 drwxr-xr-x    2 root     root            0 Jan  1  2007 .

     38    0 drwxr-xr-x    4 root     root            0 Jan  1 04:40 ..

 

/dev/snd:

    338    0 drw-r--r--    2 root     root            0 Jan  1 02:22 .

     38    0 drwxr-xr-x    4 root     root            0 Jan  1 04:40 ..

    339    0 crwxrwxrwx    1 root     root     116,   0 Jan  1 02:22 controlC0

    340    0 crwxrwxrwx    1 root     root     116,  24 Jan  1 02:22 pcmC0D0c

    341    0 crwxrwxrwx    1 root     root     116,  16 Jan  1 02:22 pcmC0D0p

    342    0 crwxrwxrwx    1 root     root     116,  33 Jan  1 02:22 timer

root:/>

 

My Kernel config relating Sound is as follows:

 

#

# Sound

#

CONFIG_SOUND=y

 

#

# Advanced Linux Sound Architecture

#

CONFIG_SND=y

CONFIG_SND_TIMER=y

CONFIG_SND_PCM=y

# CONFIG_SND_SEQUENCER is not set

# CONFIG_SND_MIXER_OSS is not set

# CONFIG_SND_PCM_OSS is not set

# CONFIG_SND_DYNAMIC_MINORS is not set

# CONFIG_SND_SUPPORT_OLD_API is not set

CONFIG_SND_VERBOSE_PROCFS=y

CONFIG_SND_VERBOSE_PRINTK=y

CONFIG_SND_DEBUG=y

CONFIG_SND_DEBUG_DETECT=y

CONFIG_SND_PCM_XRUN_DEBUG=y

 

#

# Generic devices

#

# CONFIG_SND_DUMMY is not set

# CONFIG_SND_MTPAV is not set

# CONFIG_SND_SERIAL_U16550 is not set

# CONFIG_SND_MPU401 is not set

 

#

# ALSA Blackfin devices

#

# CONFIG_SND_BLACKFIN_AD1836 is not set

# CONFIG_SND_BFIN_AD73311 is not set

# CONFIG_SND_BFIN_AD73322 is not set

 

#

# System on Chip audio support

#

CONFIG_SND_SOC=y

CONFIG_SND_BF5XX_SOC=y

CONFIG_SND_MMAP_SUPPORT=y

CONFIG_SND_BF5XX_SOC_I2S=y

CONFIG_SND_BF5XX_SOC_SSM2602=y

CONFIG_SND_BF5XX_SOC_SSM2602_ADDR=0x1b

# CONFIG_SND_BF5XX_SOC_BF5xx is not set

CONFIG_SND_BF5XX_SPORT_NUM=0

# CONFIG_SND_BF5XX_HAVE_COLD_RESET is not set

CONFIG_SND_SOC_SSM2602=y

 

#

# Open Sound System

#

# CONFIG_SOUND_PRIME is not set

 

When I don't use mmap the sound is working. Does anyone have to hint for me how to solve this?

QuoteReplyEditDelete

 

 

2009-06-24 09:00:43     Re: alsa mmap doesn't work in 2008R1.5 on bf527

Mike Frysinger (UNITED STATES)

Message: 76240   

 

the mmap() code was implemented for the AD1980 only.  if you want to use it with other codecs, you'll probably have to write your own alsa card configuration file.  look in lib/alsa-lib/Makefile and the referenced files.

 

QuoteReplyEditDelete

 

 

2009-06-24 09:18:31     Re: alsa mmap doesn't work in 2008R1.5 on bf527

Stefan Wanja (GERMANY)

Message: 76241   

 

Do you mean by writing my own /usr/share/alsa/alsa.conf file I can get it working? Or do I have to edit some configuration in the source code and rebuild it to make it work?

 

The ssm2602 kernel module itself has support for mmap, is that right?

QuoteReplyEditDelete

 

 

2009-06-24 10:10:25     Re: alsa mmap doesn't work in 2008R1.5 on bf527

Stefan Wanja (GERMANY)

Message: 76251   

 

I'm confused. As I have understood this so far, implementing mmap is not codec specific. It depends only the sport and dma implementation which is shared by some codecs? And the implementation in 2008R1.5 seems to include mmap. That is the kernel part of it. Does alsa-lib and it's config files have anything to do with mmap (codec specific)?

QuoteReplyEditDelete

 

 

2009-06-24 23:37:22     Re: alsa mmap doesn't work in 2008R1.5 on bf527

Cliff Cai (CHINA)

Message: 76286   

 

Try 2009R1 ,it supports mmap for ssm2602.

 

 

 

Cliff

QuoteReplyEditDelete

 

 

2009-06-30 06:59:37     Re: alsa mmap doesn't work in 2008R1.5 on bf527

Stefan Wanja (GERMANY)

Message: 76518   

 

Hey Cliff,

 

thanks for your response. I've been working with the trunk version recently and there it was working, right. What I am interested in is, what is the important change that happened from 2008 to 2009? When I look at the kernel sound driver files the changes seem to be not very complex. Was there an important change in alsa lib? I'm asking because we want to develop a new driver for the codecs we are using. Could you give me some advice or point me to some?

 

Kind regards,

 

Stefan

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