Hello Dramesh,
I confirm that the I2S4 pinmux configuration is set correctly :
Bank: 1 Reg: 0x70003144 Val: 0x00000044 → dap4_fs_pj4
Bank: 1 Reg: 0x70003148 Val: 0x00000054 → dap4_din_pj5
Bank: 1 Reg: 0x7000314c Val: 0x00000044 → dap4_dout_pj6
Bank: 1 Reg: 0x70003150 Val: 0x00000044 → dap4_sclk_pj7
We resolved our problem. The jetson nano produces now clocks (FSYNC and BCLK) and I2S is working.
We finally get to make the i2S work by modifying register values in U-Boot, as described in this post (Audio I2S on 40 Pin Connector - #17 by jonathanh).
We try now to configure correctly the device tree to avoid manually entering the U-Boot each time we boot up.
We modified the pinmux file “tegra210-porg-pinmux-p3448-0000-b00.dtsi” and now it’s OK for these registers:
# mw 0x70003144 0x6044
# mw 0x70003148 0x6044
# mw 0x7000314c 0x6044
# mw 0x70003150 0x6044
But for the last register GPIO_CNF (0x6000d204), it keep always the value 0xF0 and we have to modify it manually.
We found a temporary solution by changing the U-Boot environment variable “bootcmd” :
setenv bootcmd 'mw 0x6000d204 0; run distro_bootcmd'
saveenv
This solution doesn’t seem very good for me.
Without recompiling the u-boot, is there another solution to change the register value? (Using device tree for example)
Thank you in advance.
Best regards,
Dorian LE RENARD.