From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: Re: properties to describe a rotary encoder Date: Fri, 16 Oct 2015 12:09:21 +0200 Message-ID: <5620CCD1.8030509@zonque.org> References: <20151016095951.GA6533@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20151016095951.GA6533-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org List-Id: devicetree@vger.kernel.org Hi, On 10/16/2015 11:59 AM, Uwe Kleine-K=C3=B6nig wrote: > there is already a driver for rotary encoders described in > Documentation/devicetree/bindings/input/rotary-encoder.txt. This howe= ver > is not suitable to describe the device I have here for two reasons: >=20 > First the driver can only make use of 2 gpio lines, while the device > here has 4 lines, How does the phase diagram of that device look like, on what edges is the system supposed to trigger? > so I have 16 sectors instead of only 4. And the What's a 'sector'? > second difference is that my encoder has a detend for each sector whi= le > the driver only supports "half-period" and "full-period" (default) mo= de. > These names really only make sense for the 2 line case and mean the > encoder has detends in 2 or 1 sector respectively. >=20 > So I'm thinking about how to generalize the description to allow to a= dd > support for "my" device. >=20 > For the added gpio lines it's easy, that's just allowing more than tw= o > gpios for the "gpios" property. Doesn't the number of GPIOs already give enough information to implemen= t proper support? Maybe there's no need for any other properties here. > Currently there is a property "rotary-encoder,steps" that describes t= he > number of detends in a full turnaround. So if we stick to "steps" to > describe detends, maybe something like "sectors-per-step" (with a > default of 4) would be needed to describe what "half-period" is now. > Does this make sense? Maybe someone has a better suggestion? I'm not sure what a sector is supposed to refer to, but the number of steps per 360=C2=B0 is something that can vary for both 2-line and 4-li= ne versions of a rotary encoder. So isn't that unrelated? Thanks, Daniel -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html