Hi Arnd, On Wed, 31 Aug 2011 18:49:37 +0200, Arnd Bergmann wrote: > On Monday 29 August 2011, Luciano Coelho wrote: > > From: Randy Dunlap <rdunlap@xxxxxxxxxxxx> > > > > Combine MFD_SUPPORT (which only enabled the remainder of the MFD > > menu) and MFD_CORE. This allows other drivers to select MFD_CORE > > without needing to also select MFD_SUPPORT, which fixes some > > kconfig unmet dependency warnings. Modeled after I2C kconfig. > > > > [Forward-ported to 3.1-rc4. This fixes a warning when some drivers, > > such as RADIO_WL1273, are selected, but MFD_SUPPORT is not. -- Luca] > > > > Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxx> > > Reported-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> > > Cc: Jean Delvare <khali@xxxxxxxxxxxx> > > Cc: Tony Lindgren <tony@xxxxxxxxxxx> > > Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> > > Signed-off-by: Luciano Coelho <coelho@xxxxxx> > > --- > > > > I guess this should fix the problem. I've simple forward-ported > > Randy's patch to the latest mainline kernel. I don't know via which > > tree this should go in, though. > > > > NOTE: I have not tested this very thoroughly. But at least > > omap2plus stuff seems to work okay with this change. MFD_SUPPORT is > > also selected by a couple of "tile" platforms defconfigs, but I guess > > the Kconfig system should take care of it. > > Doing this is a good idea, but incidentally I have just spent some time > with the same problem and ended up with a solution that I like better, > which is removing CONFIG_MFD_SUPPORT altogether. > > The point is that there is no use enabling MFD_CORE if you don't also > enable any of the specific drivers. Same holds for pretty much every subsystem, right? > MFD_SUPPORT was added as a 'menuconfig' > before we had Kconfig warn about broken dependencies, so everything was > fine. Since Kconfig now issues the warnings, I think it would be better > to just turn the MFD menu into a plain 'menu' and remove all the > 'depends on MFD_SUPPORT' and 'select MFD_SUPPORT' lines from the other > Kconfig files. This would make it impossible to turn off all MFD drivers at once. I think this is considered a feature, at least I find it very convenient to be able to "kill" a subsystem completely. And in the past few years many subsystems were turned from menu to menuconfig for this reason. But maybe MFD is a special case here. Anyway, if you want your patch to be applied, you'll have to send it for review first, as at this point all we have is Luciano's proposal. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html