How to manually control the Camera_GPIO pins on the CM4 to maintain a high voltage level?

[wupanhao]

We have developed a product based on the CM4 and CM5, modifying the CSI camera interface to a mini HDMI format. We want to dynamically load the corresponding camera driver after the user plugs in the camera. This has been achieved on the CM5 by enabling the camera power [GPIO34] and reading the corresponding I2C bus device information. However, on the CM4, the Camera_GPIO pin is automatically controlled by the system driver, which doesn't meet our needs. We would like to know how to manually control the Camera_GPIO pin [pin 97] on the CM4 or configure it to remain enabled. Any method that allows for dynamic loading of the camera driver would be helpful (on the standard Raspberry Pi OS, the camera driver will never load successfully after an initial failure).

[6by9]

Both CM4 and CM5 use the normal regulator framework to control the camera GPIO, using nodes cam1_reg and cam0_reg.
In the case of CM4 those are the same node as they share a single GPIO.

I'm going to guess that you've used dtparam=cam0_reg=0 to disable cam0_reg on CM5 and hence free GPIO 34 for general use.

The same should work on CM4, but note that the camera GPIO is on gpiochip1 line 5, not on the main SoC. (gpioinfo would tell you that, and lists what, if anything, has claimed the GPIO)