Who calls the probe() of driver

Long story short: the probe() function of the driver is called as a result of calling the register_driver for that specific bus. More precisely, it's called by the probe() of that bus_type structure. In your case: i2c_bus_type.

Here's the call chain in your I2C case:

  • i2c_register_driver
  • driver_register
  • bus_add_driver
  • driver_attach
  • __driver_attach (for your device)
  • driver_probe_device
  • really_probe
  • i2c_device_probe (this is what dev->bus->probe is for an i2c driver)
  • your_probe_function

I have prepared a graph that traces platform drive's probe function. You are working with I2C driver which AFAIK is a platform driver. I hope this helps you to trace the issue.

enter image description here

Also, look into following link to see the discussion on kernelnewbies.

https://www.mail-archive.com/kernelnewbies%40kernelnewbies.org/msg12423.html

Tags:

Linux Kernel

Linux Device Driver

Recent Posts