On Fri, Aug 11, 2017 at 9:37 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Fri, Aug 11, 2017 at 3:30 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote: >> Since "/firmware" does not have its own "compatible" property as it's >> just collection of nodes representing firmware interface, it's sub-nodes >> are not populated during system initialization. >> >> Currently different firmware drivers search the /firmware/ node and >> populate the sub-node devices selectively. Instead we can populate >> the /firmware/ node during init to avoid more drivers continuing to >> populate the devices selectively. >> >> This patch adds initcall to achieve the same. > > Hmm, I'm a bit skeptical whether representing anything under /firmware > as a platform device is a good idea. Having a more structured way to > probe those seems like a good idea, but maybe a different subsystem > would be more appropriate. > > I do realize that a 'platform_device' has become a rather generic abstraction > for almost anything, but at some point we might want to draw the line > of what is a platform_device. I guess the question how are they different? Most of what's under drivers/firmware/ are platform drivers. I think they are mostly either smc calls or mailbox interfaces. Would there be any advantage to creating an smc bus or mailbox bus? It's easier to convert from a platform driver to some new bus_type than convert from a non-driver if we decide to do that later. The other approach would be to do a whitelist of compatibles. That's what's being done for /reserved-memory (currently there's one (ramoops) and a 2nd is being added). Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
