Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757579AbbEEUks (ORCPT ); Tue, 5 May 2015 16:40:48 -0400 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:57477 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751537AbbEEUkn (ORCPT ); Tue, 5 May 2015 16:40:43 -0400 User-Agent: K-9 Mail for Android In-Reply-To: <5547CE60.5000300@metafoo.de> References: <1430736604-22119-1-git-send-email-daniel.baluta@intel.com> <1430736604-22119-4-git-send-email-daniel.baluta@intel.com> <5547CE60.5000300@metafoo.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Subject: Re: [PATCH v5 3/4] iio: trigger: Introduce IIO hrtimer based trigger From: Jonathan Cameron Date: Tue, 05 May 2015 14:51:05 +0100 To: Lars-Peter Clausen , Daniel Baluta CC: jlbec@evilplan.org, knaack.h@gmx.de, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, octavian.purdila@intel.com, pebolle@tiscali.nl, patrick.porlan@intel.com, adriana.reus@intel.com, constantin.musca@intel.com, marten@intuitiveaerial.com Message-ID: <0944C1CC-6F9C-49C5-8195-994413B68680@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2335 Lines: 80 On 4 May 2015 20:54:08 GMT+01:00, Lars-Peter Clausen wrote: >On 05/04/2015 12:50 PM, Daniel Baluta wrote: >[...] >> +IIO_HRTIMER_INFO_ATTR(sampling_frequency, S_IRUGO | S_IWUSR, >> + iio_hrtimer_info_show_sampling_frequency, >> + iio_hrtimer_info_store_sampling_frequency); > >I wonder if the sampling frequency should be configurable the regular >IIO >API, just like any other IIO device. But things like min/max sampling >frequency should be configured in configfs. Would have to be in the trigger dir rather than device... Makes sense to put it there. Limits on it here seem like a sensible idea. > >[...] >> +#endif /* CONFIGFS_FS */ >> + >[...] >> +static struct iio_sw_trigger *iio_trig_hrtimer_probe(const char >*name) >> +{ >[...] >> +#ifdef CONFIG_CONFIGFS_FS >> + config_group_init_type_name(&trig_info->swt.group, name, >> + &iio_hrtimer_type); >> +#endif > >This should probably have a helper function in the sw trigger core, >that >gets stubbed out when CONFIG_FS is disabled. Otherwise we'll see the >same >#ifdef in every software trigger driver. >[...] >> +} >> + >> +static int iio_trig_hrtimer_remove(struct iio_sw_trigger *swt) >> +{ >> + struct iio_hrtimer_info *trig_info; >> + >> + trig_info = iio_trigger_get_drvdata(swt->trigger); >> + >> + hrtimer_cancel(&trig_info->timer); >> + >> + iio_trigger_unregister(swt->trigger); >> + iio_trigger_free(swt->trigger); > >There is a bit of a race condition here. hrtimer_cancel() should be >called >between unregister and free, otherwise it might be re-armed before it >is >unregistered. > >> + kfree(trig_info); >> + >> + return 0; >> +} >> + >> +struct iio_sw_trigger_ops iio_trig_hrtimer_ops = { > >const > >> + .probe = iio_trig_hrtimer_probe, >> + .remove = iio_trig_hrtimer_remove, >> +}; >[...] > >-- >To unsubscribe from this list: send the line "unsubscribe linux-iio" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html -- Sent from my Android device with K-9 Mail. Please excuse my brevity. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/