On Mon, May 25, 2015 at 02:40:10PM +0300, Heikki Krogerus wrote: > Hi, > > > Why do we even need that? If you take patch that makes ulpi_init a > > subsys_initcall you won't have this problem, and no additional weird > > hacks and errors will be needed > > Using subsys_initcall will work around the problem for now, but I > would not make the assumption that there will never be ulpi phy > drivers and ulpi interface drivers that don't use subsys_initcall > themselves. By checking the old phy drivers at drivers/usb/phy/, at > least so far it hasn't been uncommon for them to use subsys_initcall. > > I would much prefer to have a proper fix for this issue instead of > just working around it, but we need to use subsys_initcall in any > case. > > > >> > + /* Was the bus registered successfully? */ > > >> > + if (!ulpi_bus.p) > > >> > + return -ENODEV; > > >> > > >> Ick, no, don't go mucking around in the bus internals like this, that's > > >> not ok. You should either "know" the bus is registered, or something is > > >> really wrong with the design here. > > > can't we use a variable which can be initialized to 1 in ulpi_init() if > > > the bus registers successfully and later check that? > > Just a note. We should also be aware if the bus registration failed or > if it just hasn't been loaded yet. > > If we used a variable like that, I guess it could initially have the > value -EAGAIN. If bus_register returns error, we store -ENODEV to it. > If bus_register succeeds we store 0 to it. I don't know if we can just > store the return value from bus_register to it. > > In ulpi_register_driver and ulpi_register_interface we can then just > return it if it has a value other then 0. > > But couldn't we add a helper function to drivers/base/bus.c that the > bus drivers can use to at least check was the bus already loaded or > not? It looks like there are a couple of bus drivers that use the > struct bus member "p" to check that. > > Greg, what do you think? I think your design is wrong if you need to worry about this :) If there are other bus drivers that do this, I'll go fix them up, pointers to those files would be appreciated. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
