RPI4 with HyperPixel 4 observations and a segfault

[Musiker]

Hi all,
Just started working with the sensor and RPI4 where I have a https://learn.pimoroni.com/article/getting-started-with-hyperpixel-4 (no touch) mounted and thus have to use the I2C routed through the Pixel4 (Its enumerated as dev/i2c-22 on my system)
So I just want to share my experience for others working on similar platform..

Got the Sensor working using the linux driver on Raspberry Pi OS 11 (bullseye) 64 bit
Two issues I had to solve before I got any picture:

1. I had to comment out I2C_M_NOSTART in line 60 of functions/MLX90640_LINUX_I2C_Driver.cpp - With the I2C_M_NOSTART - The i2c did not setup reads and I only got 0xFFFF's.
2. Then when I run a sample code I just get a "Segmentation fault" I root caused it to MLX90640_BadPixelsCorrection where the pix variable is incremented beyond the 5 that is available in the pixels[5] pointer given as input.. I made a hack where I just break the while loop if pix > 4