From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6CB4C432BE for ; Thu, 2 Sep 2021 12:25:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B32A1610CC for ; Thu, 2 Sep 2021 12:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344467AbhIBM0e convert rfc822-to-8bit (ORCPT ); Thu, 2 Sep 2021 08:26:34 -0400 Received: from relay6-d.mail.gandi.net ([217.70.183.198]:35481 "EHLO relay6-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344436AbhIBM0c (ORCPT ); Thu, 2 Sep 2021 08:26:32 -0400 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id 2ED24C0002; Thu, 2 Sep 2021 12:25:32 +0000 (UTC) Date: Thu, 2 Sep 2021 14:25:26 +0200 From: Miquel Raynal To: "Sa, Nuno" Cc: Jonathan Cameron , Lars-Peter Clausen , Thomas Petazzoni , "linux-iio@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 15/16] iio: adc: max1027: Support software triggers Message-ID: <20210902142526.55fca207@xps13> In-Reply-To: References: <20210818111139.330636-1-miquel.raynal@bootlin.com> <20210818111139.330636-16-miquel.raynal@bootlin.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.7 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Nuno, "Sa, Nuno" wrote on Fri, 20 Aug 2021 07:58:25 +0000: > > -----Original Message----- > > From: Miquel Raynal > > Sent: Wednesday, August 18, 2021 1:12 PM > > To: Jonathan Cameron ; Lars-Peter Clausen > > > > Cc: Thomas Petazzoni ; linux- > > iio@vger.kernel.org; linux-kernel@vger.kernel.org; Miquel Raynal > > > > Subject: [PATCH 15/16] iio: adc: max1027: Support software triggers > > > > [External] > > > > Now that max1027_trigger_handler() has been freed from handling > > hardware > > triggers EOC situations, we can use it for what it has been designed in > > the first place: trigger software originated conversions. In other > > words, when userspace initiates a conversion with a sysfs trigger or a > > hrtimer trigger, we must do all configuration steps, ie: > > 1- Configuring the trigger > > 2- Configuring the channels to scan > > 3- Starting the conversion (actually done automatically by step 2 in > > this case) > > 4- Waiting for the conversion to end > > 5- Retrieving the data from the ADC > > 6- Push the data to the IIO core and notify it > > > > Add the missing steps to this helper and drop the trigger verification > > hook otherwise software triggers would simply not be accepted at all. > > > > Signed-off-by: Miquel Raynal > > --- > > drivers/iio/adc/max1027.c | 26 ++++++++++++++------------ > > 1 file changed, 14 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c > > index 8c5995ae59f2..bb437e43adaf 100644 > > --- a/drivers/iio/adc/max1027.c > > +++ b/drivers/iio/adc/max1027.c > > @@ -413,17 +413,6 @@ static int max1027_debugfs_reg_access(struct > > iio_dev *indio_dev, > > return spi_write(st->spi, val, 1); > > } > > > > -static int max1027_validate_trigger(struct iio_dev *indio_dev, > > - struct iio_trigger *trig) > > -{ > > - struct max1027_state *st = iio_priv(indio_dev); > > - > > - if (st->trig != trig) > > - return -EINVAL; > > - > > - return 0; > > -} > > - > > static int max1027_set_cnvst_trigger_state(struct iio_trigger *trig, > > bool state) > > { > > struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); > > @@ -512,7 +501,21 @@ static irqreturn_t max1027_trigger_handler(int > > irq, void *private) > > > > pr_debug("%s(irq=%d, private=0x%p)\n", __func__, irq, > > private); > > > > + ret = max1027_configure_trigger(indio_dev); > > + if (ret) > > + goto out; > > + > > + ret = max1027_configure_chans_to_scan(indio_dev); > > + if (ret) > > + goto out; > > + > > + ret = max1027_wait_eoc(indio_dev); > > + if (ret) > > + goto out; > > + > > ret = max1027_read_scan(indio_dev); > > There's something that I'm not getting... How are we checking that > we have software triggers? This API is called only if the device > allocates it's own trigger which will happen if there's a spi IRQ. > > I'm probably missing something as this series is fairly big but the way > I would do it is (in the probe): > > - always call 'devm_iio_triggered_buffer_setup()' function and properly use > buffer ops [1] (for example, you can use 'validate_scan_mask()' to setup the > channels to read); > - only allocate a trigger if an IRQ is present in which case, we assume HW > triggering is supported. I think these are the exact steps that are enforced in the next patch, I can squash them if you wish but I think it makes sense to have it in two steps. Thanks, Miquèl