Raspberry Pi Compute Module 3 / I2S / HifiBerry DAC (solved)

Eteif

January 30, 2017 12:45

None

Hi, I've used a Raspberry Pi Compute Module 1 with the HifiBerry DAC.
Now I replaced the module 1 with the Raspberry Pi Compute Module 3.
Unfortunately, I now no longer have a signal at the I2S.
I hope you can help me.

Date Votes

12 comments

Eteif January 30, 2017 12:46

aplay -l

**** Liste der Hardware-Geräte (PLAYBACK) ****
Karte 0: sndrpihifiberry [snd_rpi_hifiberry_dac], Gerät 0: HifiBerry DAC HiFi pcm5102a-hifi-0 []
  Sub-Geräte: 0/1
  Sub-Gerät #0: subdevice #0

Eteif January 30, 2017 13:08

uname -a

Linux 4.4.45-v7+ #954 SMP Fri Jan 27 19:06:40 GMT 2017 armv7l GNU/Linux


cat /boot/config.txt

disable_overscan=1
start_file=start_x.elf
fixup_file=fixup_x.dat
dtoverlay=hifiberry-dac
boot_delay=2
disable_splash=1


cat /etc/asound.conf

pcm.!default  {
 type hw
 card 0
 device 0
}
ctl.!default {
 type hw
 card 0
 device 0
}



lsmod

Module                  Size  Used by
xt_state                1293  1
iptable_mangle          1454  0
iptable_nat             1725  0
sg                     18319  0
nf_conntrack_ipv4      12912  2
nf_defrag_ipv4          1428  1 nf_conntrack_ipv4
sr_mod                 13220  0
nf_nat_ipv4             4992  1 iptable_nat
nf_nat                 12375  1 nf_nat_ipv4
cdrom                  27410  1 sr_mod
nf_conntrack           77460  4 nf_nat,xt_state,nf_nat_ipv4,nf_conntrack_ipv4
ipv6                  347556  49
iptable_filter          1409  1
ip_tables              11445  3 iptable_filter,iptable_mangle,iptable_nat
x_tables               13165  4 ip_tables,xt_state,iptable_filter,iptable_mangle
evdev                  11396  1
snd_soc_hifiberry_dac     2511  2
snd_soc_bcm2835_i2s     6354  2
bcm2835_wdt             3225  0
bcm2835_gpiomem         3040  0
snd_soc_pcm5102a        1763  1
snd_soc_core          125949  3 snd_soc_bcm2835_i2s,snd_soc_hifiberry_dac,snd_soc_pcm5102a
snd_pcm_dmaengine       3391  1 snd_soc_core
snd_pcm                75762  4 snd_soc_core,snd_soc_hifiberry_dac,snd_pcm_dmaengine
snd_seq                53119  0
snd_seq_device          3621  1 snd_seq
snd_timer              19288  2 snd_pcm,snd_seq
snd                    51908  8 snd_soc_core,snd_timer,snd_pcm,snd_seq,snd_seq_device
uio_pdrv_genirq         3164  0
uio                     8000  1 uio_pdrv_genirq

Edited by Eteif January 30, 2017 13:54

Eteif January 30, 2017 13:54

cat /boot/cmdline.txt

dwc_otg.lpm_enable=0 root=/dev/mmcblk0p2 rootfstype=ext4 noatime console=tty9 logo.nologo quiet rootwait loglevel=1 sdhci-bcm2708.enable_llm=1 dwc_otg.microframe_schedule=1 dwc_otg.fiq_fix_enable=0 dwc_otg.fiq_split_enable=0

0

HiFiBerry team January 31, 2017 08:30

Hi,

most likely a kernel patch is needed to enable the correct GPIOs. I recommend reporting this to the kernel developers:

https://github.com/raspberrypi/linux/issues

Best regards,
Daniel

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Eteif January 31, 2017 08:57


Thank you.

The Solution:

Edit the dt-blob.bin

sudo apt-get install device-tree-compiler

wget https://github.com/raspberrypi/firmware/raw/master/extra/dt-blob.dts

nano dt-blob.dts

go to pins_cm3 section and ad

            pin@p15 { function = "uart0";  termination = "pull_up"; drive_strength_mA = < 8 >; }; // RX uart0
//--------------------------------------------------------------------------------------------------------------       
            
                pin@p28 {
                        function = "pcm";
                        termination = "no_pulling";
                        drive_strength_mA = < 10 >; // pcm/i2s
                };

                pin@p29 {
                        function = "pcm";
                        termination = "no_pulling";
                        drive_strength_mA = < 10 >; // pcm/i2s
                };

                pin@p30 {
                        function = "pcm";
                        termination = "no_pulling";
                        drive_strength_mA = < 10 >; // pcm/i2s
                };

                pin@p31 {
                        function = "pcm";
                        termination = "no_pulling";
                        drive_strength_mA = < 10 >; // pcm/i2s
                };
                
//-------------------------------------------------------------------------------------------------------------- 
            pin@p46 { function = "input";   termination = "pull_up";    }; // SMPS_SCL


save the file

and convert to dt-blob.bin

sudo dtc -I dts -O dtb -o /boot/dt-blob.bin dt-blob.dts


be shure not to blacklist in /etc/modprobe.d/*

blacklist i2c-bcm2708
blacklist snd-soc-pcm512x
blacklist snd-soc-wm8804

reboot

0

AXM June 19, 2017 12:01

Hi,

Quite useful post.

I am also planning to use CM3 with HiFiBerry DAC+ Pro. I know that I have to connect GPIO28, 29,30,31 to the DAC+. I am a little bit confused about the i2c pins. I plan to connect it to GPIO0 (SDA) and GPIO(1). Is it correct?

Thanks

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0

HiFiBerry team June 19, 2017 12:03

Yes, you also need to connect I2C. However, I2C is GPIO2 and GPIO3.

Best regards,
Daniel

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0

AXM June 19, 2017 12:15

We have two I2Cs in CM. GPIO0 (SDA0) and GPIO1 (SCL0) & GPIO2 (SDA1) and GPIO3 (SCL1). So can I not use GPIO0 and GPIO1 for DAC+?

Thanks

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0

HiFiBerry team June 19, 2017 12:17

No you can't, except if you patch and re-compile the Linux kernel.

Best regards,
Daniel

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0

AXM June 19, 2017 12:22

Okay thanks.

But I think I can use GPIO18,19,20,21 for I2S, right?

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0

HiFiBerry team June 20, 2017 07:08

Yes, these are the GPIOs for I2S.

Best regards,
Daniel

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0

AXM June 20, 2017 08:55

okay thanks a lot

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