Re: [PATCH RFC V3.5] leds: trigger: Introduce an USB port trigger

From: Pavel Machek
Date: Mon Aug 29 2016 - 04:06:03 EST


Hi!

> >2) Having "ports" subdir with RW files, one per each existing physical port
> >In this situation we don't need "new_port" or "remove_port". If we
> >want port to be observable we just do:
> >echo 1 > 1-1
> >Implementing this solution needs reading more details from USB subsystem.
>
> The situation here is clear IMO - the number of USB ports in the system
> can change dynamically. I'm not sure if this can be handled easily with
> sysfs, where we usually expose an interface for known set of settings.
> struct attribute arrays are usually defined statically at the compile
> time and filled with the variables, that are created with DEVICE_ATTR
> macro.

sysfs already exposes current view of all usb devices. Just use it.

Pavel
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