Some parts that stood out to me: > A phone camera is not a single device. On Qualcomm SoCs, the capture path is a chain: > The bus register base moved from 0xa00 to 0x1800, and encapsulating that offset shift accounted for most of the work. > It gated the AHB register bus used by the whole camera complex, including the CCI. Without it, register accesses silently returned zero. > With the wrong numbering, CSIPHY programmed a lane mask with lane 0 missing, and the PHY never locked. > This was the main bug. Frames arrived at the right rate and size, and buf_done fired, but every pixel was zero. [...] The data path delivered frame timing, but not pixel data. > Changing the register value from PLAIN64 (0xa) to 0x0 turned the all-zero frames into real images: the maximum pixel value was 255, the full colour-bar pattern appeared, and the violations stopped.
Sorry if not, but it seems like so much uses AI nowadays.