Use PiSound on C2 with Mainline Kernel

[federico]

Armbianmonitor:

http://ix.io/1z0U

Hi All,

I'm tring to make Ocroid C2 working with PiSound shield.

https://github.com/BlokasLabs/pisound/tree/master/pisound-module

 

I've compiled the module, an I'm able to install it properly.

I've changed the DTS in this way

--- pisound-overlay.dts	2019-01-22 23:28:59.460427794 +0000
+++ pisound-overlay_odroid.dts	2019-01-23 01:48:20.198204778 +0000
@@ -20,10 +20,9 @@
 /dts-v1/;
 /plugin/;
 
-#include <dt-bindings/gpio/gpio.h>
-
+#include "/usr/src/linux-headers-4.19.15-meson64/include/dt-bindings/gpio/gpio.h"
 / {
-	compatible = "brcm,bcm2708";
+	compatible = "amlogic,meson-gxbb";
 
 	fragment@0 {
 		target = <&spi0>;

 

I've followed guide line here

https://docs.armbian.com/User-Guide_Allwinner_overlays/
https://wiki.odroid.com/odroid-c2/application_note/gpio/spi#c2
https://forum.armbian.com/topic/8353-use-gpio-on-c2-with-mainline-kernel/

 

but still getting trouble.

 

Do you've any tips? It spi0 the proper target to use? Do I need to displable something in C2 dts?

 

thanks

Federico

[TonyMac32]

Kernel 4.19 has a software spi0 and spidev, but honestly I'm not sure of the rest of the requirements for that board, odds are the I2S isn't going to line up.  

 

https://docs.google.com/spreadsheets/d/1dJq7MM1_zA5HtXywDMZ9HMKyPaNgGmkxnuz3wYuk4s8/edit?usp=sharing

[federico]

Thanks for share the document Tony.

The pinout of pisound are referenced here https://blokas.io/pisound/docs/Specs/

 

meanwhile I've tried to upgrade the i2s driver name inside the pisound kernel module with the one used by odroid c2 but still no luck.

diff --git a/pisound-module/pisound.c b/pisound-module/pisound.c
index ab9ea1f..538fca6 100644
--- a/pisound-module/pisound.c
+++ b/pisound-module/pisound.c
@@ -939,9 +940,9 @@ static struct snd_soc_dai_link pisnd_dai[] = {
        {
                .name           = "pisound",
                .stream_name    = "pisound",
-               .cpu_dai_name   = "bcm2708-i2s.0",
+               .cpu_dai_name   = "aml-i2s-dai.0",
+               .platform_name  = "aml-i2s.0",
                .codec_dai_name = "snd-soc-dummy-dai",
-               .platform_name  = "bcm2708-i2s.0",
                .codec_name     = "snd-soc-dummy",
                .dai_fmt        =
                        SND_SOC_DAIFMT_I2S |

 

[TonyMac32]

The issue here is, there is a pin compatibility problem from what I can see.  The C2 has the 40-pin header wired physically differently in terms of I2S.  The "Le Potato" board looks to have the right pins in the right place, as does the Tinker Board, and the Tritium series.  I'm sure there are others, but I haven't gotten into all of the GPIO's yet, the document I shared is for my own use, but I'm happy to share it.  It doesn't have anything special in it, other than having all the baords in one place, in theory, so you don't have to scour the internet and figure out the various vendor formats to document it.  And I go through the datasheets and look at alternate functions of the GPIO.