Platform drivers and DTs

Platform drivers also work with DTs. It is the recommended way to deal with platform devices nowadays, and there is no need to touch board files anymore, or even to recompile the kernel when a device's property changes. If you remember, in the previous chapter we discussed OF match style, which is a matching mechanism based on DTs. Let's see in the following section how it works.

OF match style

OF match style is the first matching mechanism performed by the platform core in order to match devices with their drivers. It uses a device tree's compatible property to match the device entry in of_match_table, which is a field of the struct driver substructure. Each device node has a compatible property, which is a string or a list of strings. Any platform driver that declares one of the strings listed in the compatible property will trigger a match and will see its probe function executed.

A DT match entry is described in the kernel as an instance of the struct of_device_id...