Jetson Nano u-boot device tree altering or I2C in C using

Robotics & Edge Computing Jetson & Embedded Systems Jetson Nano
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Good afternoon, Nvidia! I tried to understand where is u-boot dts file but I failed. When I building u-boot it appears that tegra210-p3450-0000.dtb appearing from nowhere. I have to alter I2C implementation but I cannot. Somewhat Linux can see more devices on I2C then u-boot and I have to fix this.
Or I should be able to use I2C from coding in u-boot. I tried to define CONFIG_SYS_I2C=y to be able to use I2C from in u-boot coding but I cannot because your building system ignores exact config. How I understood you redefining this with CONFIG_SYS_I2C_TEGRA=y but CONFIG_SYS_I2C=y providing headers and ability to programming in u-boot using this and you redefined config is not providing this - only command so I cannot use i2s in C code in u-boot.

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Hi ATAineri,

Are you using the devkit or custom board for Jetson Nano?
What’s your Jetpack version in use?

How did you perform this?

Do you want to use I2C or I2S?

Please also share the full flash log for further check.

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Hi! I added CONFIG_SYS_I2C=y in defconfig but it is not pass through to .config. I already saw something like this in your kernel and it was the problem that this config conflicted with you driver and it was undefined.
I already workarounded this problem by means of u-boot scripting. The problem that I don’t see my I2C devices was that I2C1 in u-boot was not the same I2C1 from Jetson module and not the same I2C1 from Linux. All of this I2C1 is a different things and it mixed me up. My I2C1 was not defined at all - I described it in DTS and now everything is working fine.

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But if it is possible - I want to be able to use I2C from U-BOOT sources if you could help me

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Please use the following command in U-boot for I2C.

# i2c dev 3
# i2c probe
Valid chip addresses: 50 57
# i2c md 0x50 0x00.1 0x100
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Yes, but it is already in u-boot, but I want to use it not in u-boot shell but in u-boot sources. That’s why I wanted CONFIG_SYS_I2C=y

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You could refer to mxc_i2c.c for details.

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Everything is static here - it is not for using in another c file, it’s only for using in u-boot shell with the command

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