On 12/17/19 10:08 PM, Uwe Kleine-König wrote: > On Tue, Dec 17, 2019 at 09:27:13PM +0100, Jacek Anaszewski wrote: >> On 12/17/19 6:21 PM, Greg Kroah-Hartman wrote: >>> On Tue, Dec 17, 2019 at 05:23:13PM +0100, Uwe Kleine-König wrote: >>>> On Tue, Dec 17, 2019 at 04:27:24PM +0100, Greg Kroah-Hartman wrote: >>>>> On Tue, Dec 17, 2019 at 04:07:36PM +0100, Uwe Kleine-König wrote: >>>>>> Usage is as follows: >>>>>> >>>>>> myled=ledname >>>>>> tty=ttyS0 >>>>>> >>>>>> echo tty > /sys/class/leds/$myled/trigger >>>>>> cat /sys/class/tty/$tty/dev > /sys/class/leds/$myled/dev >>>>> >>>>> Is this the correct instructions? Aren't you looking for a major/minor >>>>> number instead in your sysfs file? >>>> >>>> This is correct, yes, at least it works as intended on my machine. >>>> >>>> /sys/class/tty/$tty/dev produces $major:$minor and that's what the >>>> led-trigger consumes. >>> >>> Ugh, nevermind, I totally read that wrong, I was thinking "echo" instead >>> of cat. My fault, what you wrote is correct. Should that be documented >>> somewhere in a Documentation/ABI/ file so that people know how to use >>> this new sysfs file? How are led triggers documented? >> >> LED triggers have their corresponding entries in Documentation/ABI. >> >> Uwe, you already did that for netdev trigger: >> >> Documentation/ABI/testing/sysfs-class-led-trigger-netdev >> >> It would be nice to have one for this too. >> >> There are also less formal docs in Documentation/leds, e.g.: >> >> Documentation/leds/ledtrig-usbport.rst > > I'd put into Documentation/ABI/testing/sysfs-class-led-trigger-tty: > > What: /sys/class/leds/<led>/dev > Date: Dec 2019 > KernelVersion: 5.6 > Contact: linux-leds@xxxxxxxxxxxxxxx > Description: > Specifies $major:$minor of the triggering tty Yes, that should be fine. -- Best regards, Jacek Anaszewski
