From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753922AbbKXJpj (ORCPT ); Tue, 24 Nov 2015 04:45:39 -0500 Received: from smtp-out-194.synserver.de ([212.40.185.194]:1105 "EHLO smtp-out-188.synserver.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753583AbbKXJpf (ORCPT ); Tue, 24 Nov 2015 04:45:35 -0500 X-SynServer-TrustedSrc: 1 X-SynServer-AuthUser: lars@metafoo.de X-SynServer-PPID: 6263 Message-ID: <565431BB.2020904@metafoo.de> Date: Tue, 24 Nov 2015 10:45:31 +0100 From: Lars-Peter Clausen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.8.0 MIME-Version: 1.0 To: Martin Kepplinger , Jonathan Cameron , knaack.h@gmx.de, pmeerw@pmeerw.net, christoph.muellner@theobroma-systems.com, mfuzzey@parkeon.com CC: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Martin Kepplinger Subject: Re: [PATCH 1/3] iio: mma8452: add freefall detection for Freescale's accelerometers References: <1447267094-2248-1-git-send-email-martink@posteo.de> <5647778E.3090106@kernel.org> <56478136.3040200@posteo.de> <5647857D.5050902@kernel.org> <564B7F02.4020709@posteo.de> <5653F3A1.6010905@posteo.de> In-Reply-To: <5653F3A1.6010905@posteo.de> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/24/2015 06:20 AM, Martin Kepplinger wrote: > Am 2015-11-17 um 20:24 schrieb Martin Kepplinger: >> Am 2015-11-14 um 20:03 schrieb Jonathan Cameron: >>> On 14/11/15 18:45, Martin Kepplinger wrote: >>>> Am 2015-11-14 um 19:03 schrieb Jonathan Cameron: >>>>> On 11/11/15 18:38, Martin Kepplinger wrote: >>>>>> This adds freefall event detection to the supported devices. It adds >>>>>> the in_accel_x&y&z_mag_falling_en iio event attribute, which activates >>>>>> freefall mode. >>>>>> >>>>>> In freefall mode, the current acceleration values of all activated axis >>>>>> are added and if the *sum* falls *under* the threshold specified >>>>>> (in_accel_mag_falling_value), the appropriate IIO event code >>>>>> is generated. >>>>>> >>>>>> By enabling freefall mode (in_accel_x&y&z_mag_falling_en) >>>>>> all 3 axis are enabled too as this describes a classic freefall >>>>>> detection. Of course the user is free to disable one or more directions. >>>>>> >>>>>> The values of rising and falling versions of various sysfs files are >>>>>> shared, which is compliant to the IIO specification. >>>>>> >>>>>> This is what the sysfs "events" directory for these devices looks >>>>>> like after this change: >>>>>> >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_mag_falling_period >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_mag_falling_value >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_mag_rising_period >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_mag_rising_value >>>>>> -r--r--r-- 4096 Oct 23 08:45 in_accel_scale >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_x&y&z_mag_falling_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_x_mag_falling_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_x_mag_rising_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_y_mag_falling_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_y_mag_rising_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_z_mag_falling_en >>>>>> -rw-r--r-- 4096 Oct 23 08:45 in_accel_z_mag_rising_en >>>>>> >>>>>> Signed-off-by: Martin Kepplinger >>>>>> Signed-off-by: Christoph Muellner >>>>> Looks pretty good to me (other than obviously the bits Lars already >>>>> picked up on!) >>>>> >>>>> My only real comment was that you could do the rest of the combined >>>>> possibilities whilst you are here (if you want to!) You've >>>>> picked the mostly obviously useful one though so maybe leave it >>>>> at that. >>>> >>>> I'm not sure what you mean. There is only in_accel_x&y&z_mag_falling_en >>>> documented. So my guess was to have this to enable freefall mode, taking >>>> into account the currently enabled falling axis >>>> (in_accel_x_mag_falling_en, ...). >>> Sure, but the set of modifiers allows for >>> in_accel_x&y_mag_falling_* etc and they aren't documented in this particular >>> form simply because no driver has used them yet ;) >>> >> >> >> >> I don't see how to do it in iio_event_spec only. Could you point me in >> the right direction, could well be I overlook something... >> >> I *can* add a channel for freefall purposes, something like: >> >> static const struct iio_chan_spec mma8653_channels[] = { >> MMA8652_CHANNEL(IIO_MOD_X, idx_axis_x, 10), >> MMA8652_CHANNEL(IIO_MOD_Y, idx_axis_y, 10), >> MMA8652_CHANNEL(IIO_MOD_Z, idx_axis_z, 10), >> MMA8652_CHANNEL(IIO_MOD_X_AND_Y_AND_Z, idx_axis_xyz, 10), >> IIO_CHAN_SOFT_TIMESTAMP(idx_timestamp), >> }; >> >> >> just as an example, but then of course I get more than just events: In >> the device-directory: >> >> in_accel_x&y&z_calibbias >> in_accel_x&y&z_raw >> in_accel_x_calibbias >> in_accel_x_raw >> in_accel_y_calibbias >> in_accel_y_raw >> in_accel_z_calibbias >> in_accel_z_raw >> >> >> calibbias and raw are not (really) available for x&y&z. I could >> calculate a "raw" value, but calibbias doesn't make sense here. ...But >> again, maybe I'm on the wrong path!! >> >> thanks a lot! >> >> martin >> > > Would this be the way to go? And just not support the generated file > that don't apply? The calibbias and raw properties are added because the MMA8652_CHANNEL() macro defines them. If you don't use that macro and don't set any of the info masks for your x&y&z channel, but instead set the the event spec you get a channel that only has events. - Lars