agherzan / meta-raspberrypi

Yocto/OE BSP layer for the Raspberry Pi boards
https://www.yoctoproject.org/
MIT License
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linux: Enable Broadcom STB I2C bus driver #1385

Open eigendude opened 3 weeks ago

eigendude commented 3 weeks ago

- What I did

This PR enables the Broadcom STB I2C bus driver in the kernel config.

Without this change, when I enable the GPU on my Pi 4, my HDMI TFT display shows U-boot doing its thing then goes blank.

Enabling the STB I2C bus fixes the problem by letting Linux communicate through the Display Data Channel (DDC) to allow the TFT display to work.

- How I did it

I enabled the CONFIG_I2C_BRCMSTB option in vc4graphics.cfg to ensure proper support for the brcm,bcm2711-hdmi-i2c device node.

Without this configuration, the I2C bus associated with HDMI on Broadcom BCM2711-based systems may fail to probe, causing issues with HDMI communication and display initialization.

Additionally, this resolves potential deferred probe issues observed in the kernel logs, ensuring the correct initialization of the HDMI I2C bus.