How do I send a reset signal on pin 6 under linux using sysfs?
If you are referring to pin 6 on the 40 pin gpio connector, you don’t.
That pin is an INPUT pin. If you short it to GND, it will cause the SoC to go into reset.
If you are referring to pin 6 of the CSI camera connector, that will be configured in DTS and managed by the camera driver.
So ultimately, the answer to your question is “you don’t”.
Got it. So I hook up pin25 (GPIOB_24 => gpio 56) to pin 6, I could reset the device via sysfs by writing 1 to gpio 56.
But I can’t seem to get the other GPIO pins to work. pin 28, GPIO_A22 does not seem to correspond to gpio 22. Writing 1 to gpio 22 does not light up the LED I placed on that pin.