On Sun, Jul 08, 2018 at 02:31:49AM +0200, Javier Martinez Canillas wrote: > Hi Greg, > > On 07/07/2018 05:59 PM, Greg Kroah-Hartman wrote: > > On Thu, Jun 28, 2018 at 12:06:56AM +0200, Javier Martinez Canillas wrote: > >> With Device Trees (DT), the dependencies of the devices are defined in the > >> DT, then the drivers parse that information to lookup the needed resources > >> that have as dependencies. > >> > >> Since drivers and devices are registered in a non-deterministic way, it is > >> possible that a device that is a dependency has not been registered yet by > >> the time that is looked up. > >> > >> In this case the driver that requires this dependency cannot probe and has > >> to defer it. So the driver core adds it to a list of deferred devices that > >> is iterated again every time that a new driver is probed successfully. > >> > >> For debugging purposes it may be useful to know what are the devices whose > >> probe function was deferred. Add a debugfs entry showing that information. > >> > >> $ cat /sys/kernel/debug/devices_deferred > >> 48070000.i2c:twl@48:bci > >> musb-hdrc.0.auto > >> omapdrm.0 > >> > >> This information could be obtained partially by enabling debugging, but it > >> means that the kernel log has to be parsed and the probe deferral balanced > >> with the successes. This can be error probe and has to be done in a ad-hoc > >> manner by everyone who needs to debug these kind of issues. > >> > >> Since the information is already known by the kernel, just show it to make > >> it easier to debug. > >> > >> Signed-off-by: Javier Martinez Canillas <[email protected]> > >> Reviewed-by: Mark Brown <[email protected]> > > > > This doesn't apply to my tree anymore :( > > > > I see, I made sure that it applied on top of linux-next. > > > Can you rebase and resend? > > > > I guess you want me to rebase on top of your driver-core-next branch. I think > that linux-next should pull that branch instead of the driver-core-linus one: > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/Next/Trees#n29
Both are in linux-next, it just takes a day or so for the driver-core-next branch to get merged in. thanks, greg k-h
