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

From: RafaÅ MiÅecki
Date: Wed Aug 24 2016 - 05:27:35 EST


On 24 August 2016 at 11:21, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Wed, Aug 24, 2016 at 12:03:29AM +0200, RafaÅ MiÅecki wrote:
>> From: RafaÅ MiÅecki <rafal@xxxxxxxxxx>
>>
>> This commit adds a new trigger responsible for turning on LED when USB
>> device gets connected to the specified USB port. This can can useful for
>> various home routers that have USB port(s) and a proper LED telling user
>> a device is connected.
>>
>> The trigger gets its documentation file but basically it just requires
>> specifying USB port in a Linux format (e.g. echo 1-1 > new_port).
>>
>> During work on this trigger there was a plan to add DT bindings for it,
>> but there wasn't an agreement on the format yet. This can be worked on
>> later, a sysfs interface is needed anyway for platforms not using DT.
>>
>> Signed-off-by: RafaÅ MiÅecki <rafal@xxxxxxxxxx>
>> ---
>> V2: Trying to add DT support, idea postponed as it will take more time
>> to discuss the bindings.
>> V3: Fix typos in commit and Documentation (thanks Jacek!)
>> Use "ports" sysfs file for adding and removing USB ports (thx Jacek)
>> Check if there is USB device connected after adding new USB port
>> Fix memory leak or two
>>
>> Felipe: I'd like to ask for your Ack before having this patch pushed.
>> ---
>> Documentation/leds/ledtrig-usbport.txt | 49 +++++++
>> drivers/leds/trigger/Kconfig | 8 ++
>> drivers/leds/trigger/Makefile | 1 +
>> drivers/leds/trigger/ledtrig-usbport.c | 253 +++++++++++++++++++++++++++++++++
>> 4 files changed, 311 insertions(+)
>> create mode 100644 Documentation/leds/ledtrig-usbport.txt
>> create mode 100644 drivers/leds/trigger/ledtrig-usbport.c
>
> You are adding sysfs files without adding a Documentation/ABI/ entry,
> please never do that.

This is the way all LED triggers are documented, I just blindly
assumed it's OK. Could you be a bit more helpful and help me to
understand further steps? Should I drop
Documentation/leds/ledtrig-usbport.txt and add proper entry in
Documentation/ABI/testing? Or should I keep both files? What about
current sysfs of other triggers? Should they be moved/documented in
ABI?

--
RafaÅ