Re: [PATCH v6 3/4] HID: playstation: add DualSense player LEDs support.

From: Marek Behun <marek.behun@nic.cz>
To: Roderick Colenbrander <roderick@gaikai.com>
Cc: Jiri Kosina <jikos@kernel.org>,
	"open list:HID CORE LAYER" <linux-input@vger.kernel.org>,
	linux-leds@vger.kernel.org,
	Benjamin Tissoires <benjamin.tissoires@redhat.com>,
	Pavel Machek <pavel@ucw.cz>,
	Roderick Colenbrander <roderick.colenbrander@sony.com>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>
Subject: Re: [PATCH v6 3/4] HID: playstation: add DualSense player LEDs support.
Date: Tue, 16 Feb 2021 03:37:44 +0100	[thread overview]
Message-ID: <20210216033744.123b9acd@nic.cz> (raw)
In-Reply-To: <CANndSKke4zGn2T6jC4xYtguAjixZ7n5Rf9SSY3knEhvwJ1cLyQ@mail.gmail.com>

On Mon, 15 Feb 2021 17:11:14 -0800
Roderick Colenbrander <roderick@gaikai.com> wrote:

> On Mon, Feb 15, 2021 at 4:33 PM Marek Behun <marek.behun@nic.cz> wrote:
> >
> > On Mon, 15 Feb 2021 15:00:30 -0800
> > Roderick Colenbrander <roderick@gaikai.com> wrote:
> >  
> > > What is the desired naming for these player LEDs? There is not an
> > > officially designed function based on DT bindings. So far they used
> > > "playstation::mac::ledX". When changing the naming scheme towards
> > > "hid" and removing MAC, they would be: "hid%d::led1" etcetera.  
> >
> > Hi,
> >
> > there is one more thing I forgot to mention in the LED name schema:
> >   devicename:color:function-functionEnumerator
> >
> > So LED core can for example compose a names in the format:
> >   switch0:green:lan-1
> >   switch0:green:lan-2
> >   switch0:green:lan-3
> >   switch0:green:lan-4
> >
> > In your case I think the most appropriate name would be something like
> >   hid0:color:indicator-1
> >   hid0:color:indicator-2
> >   ...  
> 
> I am trying to think if indicator is clear enough. Currently devices
> use a mixture of names, which is obviously bad (wiimote uses p1-p4 at
> the end, sony uses sony1-4 for DualShock 3, hid-nintendo uses
> player1-4). I would at least like new drivers to standardize. In
> particular in Android frameworks we have a need to map these LEDs back
> to the Java InputDevice. Finding the LEDs has been quite painful so
> far.

Thinking about it more, function "player" should theoretically be
reasonable. Maybe we should try sending a patch for review, adding this
funciton to include/dt-bindings/leds/common.h, and see what others
think of it...

> If this is what is decided, I guess we should update the Linux gamepad
> document at some point as well.
> 
> > Are these LEDs of different colors which are impossible to determine?
> > The string "hid%d::led1" you mention above does not indicate color.  
> 
> The DualSense LEDs are all white (at least so far?). On controllers
> from other brands I have seen them be red or green. So could indeed
> use: "hid%d:white".

Yes, a constant for white color is defined in headers.

> > Marek  
> 
> Thanks,
> Roderick