Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [RFC PATCHv2 1/4] drivers/otp: add initial support for OTP memory | Date | Mon, 28 Mar 2011 15:11:00 +0200 |
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On Saturday 26 March 2011, Greg KH wrote: > On Sat, Mar 26, 2011 at 12:25:03PM +0100, Arnd Bergmann wrote: > > On Saturday 26 March 2011 00:28:47 Greg KH wrote: > > > > > Yes, that is how it used to be, but then it turns out that both of them > > > are really just "subsystems" as far as it all goes. They are just ways > > > that devices are bound to drivers in a logical manner. We have patches > > > floating around that get rid of both busses and classes to merge them > > > together, which is the end goal here. I know Kay has posted detailed > > > reasons for why this all is on lkml in the past, and had working code > > > about 5 years ago, it's just been slow going... > > > > How will that work? I suppose we can't really change the directory > > structure anyway, so to users it will still look like it does today, > > even if the kernel just uses the same code for bus and class internally. > > Yes. But we can have symlinks instead of "real" /sys/class and > /sys/bus directories like we do for /sys/block today. All of the major > tools that use sysfs work properly with a /sys/subsystem/ setup today > thanks to Kay's efforts.
I see. The migration from /sys/bus to /sys/subsystem plus symlinks makes sense, but I still think that having symlinks that make sense would be better than having symlinks that are purely there for historical reasons.
One major flaw I see with registering abstract subsystems as a bus is that a bus connected to the concept of a device_driver, and there is a list of drivers with their respective devices in /sys/bus/*/drivers, which would always be empty in this case. Similarly, the /sys/bus/*/devices/*/driver symlinks for these subsystems would point to drivers on other buses, unlike the respective symlinks for real buses.
Arnd
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