[alsa-devel] SAIF configuration on imx28

[George Stefan]

2012/8/23 George Stefan <stefan.george87 at gmail.com>

>
>
> 2012/8/23 Dong Aisheng <b29396 at freescale.com>
>
>> On Thu, Aug 23, 2012 at 03:13:11PM +0800, George Stefan wrote:
>> >    2012/8/23 Dong Aisheng <b29396 at freescale.com>
>> >
>> >      On Thu, Aug 23, 2012 at 02:41:30PM +0800, George Stefan wrote:
>> >      ...
>> >      >    /*set the saif clk mux, saif0/saif1 both use saif0 clk*/
>> >      >    __raw_writel(BF_DIGCTL_CTRL_SAIF_CLKMUX_SEL(0x0),
>>   \
>> >      Should this be 0x2 if both saif0 and saif1 are using saif0 clk?
>> >      >    IO_ADDRESS(DIGCTL_PHYS_ADDR) + HW_DIGCTL_CTRL);
>> >      >    Using this configuration i am not able to receive IRQs from
>> DMA and
>> >      i
>> >      >    think the reason
>> >      >    is that SAIF is not receiving the CLK.
>> >      >    What do you think?
>> >      >    Thanks,
>> >      >    George.
>> >
>> >      Regards
>> >      Dong Aisheng
>> >
>> >    Yes, it should be 0x2 if they are using saif0 clk. but it they are
>> using
>> >    the CLK from an external device
>> >    which is master, i think that they should use an independent clock.
>> >    "In slave clocking mode, the SAIF configures the BITCLK and LRCLK
>> pins as
>> >    inputs, and
>> >    the off-chip codec is responsible for driving both clocks to the
>> >    SAIF"(imx28 reference manual)
>> >    0x0 - DIRECT - SAIF0 clock pins selected for SAIF0 input clocks, and
>> SAIF1
>> >    clock pins selected for
>> >    SAIF1 input clocks.
>> >    Am i interpreting this in the wrong way?
>> Your understand is right if all are working on slave mode.
>> But be noted that the current driver in mainline only supports master
>> mode,
>> mainly due to playback can not work on slave mode(see spec) while capture
>> can.
>> If all are in slave mode, that means the playback may not work.
>> You should make sure if your requirements really wants that.
>> And if you want to run in slave mode, you need change the mainline driver
>> to support it.
>>
>> Regards
>> Dong Aisheng
>>
>> The problem in using SAIF as master, is that in slave mode the modem uses
> short frame sync(SND_SOC_DAIFMT_DSP_A),
> which is not supported in the current driver.
>
>
I have added support for SND_SOC_DAIFMT_DSP_A
    case SND_SOC_DAIFMT_DSP_A:
                scr &= ~BM_SAIF_CTRL_DELAY;
                scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
                scr |= BM_SAIF_CTRL_JUSTIFY;
                scr |= BM_SAIF_CTRL_BITCLK_EDGE;

}
The clock is set at 256 KHZ:
 /* set the SAIF system clock as output */
        snd_soc_dai_set_sysclk(cpu_dai, IMX_SSP_SYS_CLK, 2560000,
SND_SOC_CLOCK_OUT);

I test record with:
arecord -d 5 -f S16_LE -r 8000 -c 2 1.wav

Dump for 1.wav
exdump -C 1.wav
00000000  52 49 46 46 24 71 02 00  57 41 56 45 66 6d 74 20
 |RIFF$q..WAVEfmt |
00000010  10 00 00 00 01 00 02 00  40 1f 00 00 00 7d 00 00
 |........ at ....}..|
00000020  04 00 10 00 64 61 74 61  00 71 02 00 00 00 00 00
 |....data.q......|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
 |................|
*
00004b90  00 00 00 18 00 00 30 00  00 00 00 00 00 00 00 00
 |......0.........|
00004ba0  00 07 00 00 1c 00 00 00  02 00 00 00 00 00 00 03
 |................|
00004bb0  e0 41 7c 78 07 10 c1 84  f0 e0 1e 3c 83 0f f0 c1
 |.A|x.......<....|
00004bc0  3c 78 0f 03 c1 83 f8 f0  1f 3c 83 07 f0 e1 3e 78
 |<x.......<....>x|
00004bd0  07 1f e1 83 78 f0 1f 3e  c3 07 f0 e0 3e 7c 07 0f
 |....x..>....>|..|
00004be0  e0 c3 7c f0 0f 3e c1 87  f8 e0 1e 7c 87 0f e0 c1
 |..|..>.....|....|
00004bf0  7c f8 0f 1e c1 83 f8 f0  1f 3c 83 0f f0 c1 3c f8
 ||........<....<.|
00004c00  07 1f e1 83 78 f0 1f 3e  83 07 f0 e1 3e 78 07 0f
 |....x..>....>x..|
00004c10  e0 c3 7c f0 0f 3e c3 07  f0 e0 3e 7c 87 0f e0 c1
 |..|..>....>|....|
00004c20  fc f9 0f 1e c3 87 fc f0  1f fe f3 0f f0 c1 ff fb
 |................|
00004c30  ff df c1 83 ff f0 ff ff  e7 07 ff e1 3e ff ff 1f
 |............>...|
00004c40  ff 83 fe ff ff 3f cf f7  ff ff bf ff ff ff ff ff
 |.....?..........|
00004c50  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
 |................|
*
00027120