Re: [PATCH] RFC: platform driver registering via initcall tables

[Greg KH]

On Tue, Dec 17, 2019 at 11:22:19AM +0100, Enrico Weigelt, metux IT consult wrote:
> A large portion of platform drivers doesn't need their own init/exit
> functions. At source level, the boilerplate is already replaced by
> module_platform_driver() macro call, which creates this code under
> the hood. But in the binary, the code is still there.
> 
> This patch is an attempt to remove them it, by the same approach
> already used for the init functions: collect pointers to the driver
> structs in special sections, which are then processed by the init
> code which already calls the init function vectors. For each level,
> the structs are processed right after the init funcs, so we guarantee
> the existing order, and explicit inits always come before the automatic
> registering.

No, what is so "special" about platform drivers that they require this?

If anything, we should be moving _AWAY_ from platform drivers and use
real bus drivers instead.

> Downside of apprach: cluttering init code w/ a little bit knowledge
> about driver related stuff (calls to platform_driver_register(), etc).

Exactly, don't.

> For now, only implemented for the built-in case (modules still go the
> old route). The module case is a little bit trickier: either we have to
> extend the module header (and modpost tool) or do some dynamic symbol
> lookup.
> 
> This patch is just a PoC for further discussions, not ready for mainline.
> It also changes a few drivers, just for illustration. In case the general
> approach is accepted, it will be cleaned up and splitted.

Please no, I don't see why this is even needed.

greg k-h