On Wed, May 13, 2015 at 07:50:34PM +0200, Maxime Ripard wrote: > Hi Greg, > > On Wed, May 13, 2015 at 08:37:40AM -0700, Greg Kroah-Hartman wrote: > > On Wed, May 13, 2015 at 12:26:04PM +0100, Mark Brown wrote: > > > On Tue, May 12, 2015 at 10:33:24PM +0200, Maxime Ripard wrote: > > > > > > > While this is nicer than the DT solution because of its accurate > > > > hardware > > > > representation, it's still not perfect because you might not have > > > > access to the > > > > DT, or you might be driving a completely generic device (such as a > > > > microcontroller) that might be used for something else in a different > > > > context/board. > > > > > > Greg, you're copied on this because this seems to be a generic problem > > > that should perhaps be solved at a driver model level - having a way to > > > bind userspace access to devices that we don't otherwise have a driver > > > for. The subsystem could specify the UIO driver to use when no other > > > driver is available. > > > > That doesn't really work. I've been talking to the ACPI people about > > this, and the problem is "don't otherwise have a driver for" is an > > impossible thing to prove, as you never know when a driver is going to > > be loaded from userspace. > > > > You can easily bind drivers to devices today from userspace, why not > > just use the built-in functionality you have today if you "know" that > > there is no driver for this hardware. > > What we're really after here is that we want to have an spidev > instance when we don't even have a device.
That's crazy, just create a device, things do not work without one. > And since SPI isn't really doing any kind of hotplug, the only > situation that might be problematic is if we have the DT overlays > registering new devices. I have no idea what this all is, sorry, patches would be good if you want to get your idea across. Maybe it was sent early in this thread, but I can't seem to find one... greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
