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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A24DC433EF for ; Sat, 13 Nov 2021 16:24:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 62336610F7 for ; Sat, 13 Nov 2021 16:24:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236022AbhKMQ0z (ORCPT ); Sat, 13 Nov 2021 11:26:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:49512 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235980AbhKMQ0z (ORCPT ); Sat, 13 Nov 2021 11:26:55 -0500 Received: from jic23-huawei (cpc108967-cmbg20-2-0-cust86.5-4.cable.virginm.net [81.101.6.87]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3302961077; Sat, 13 Nov 2021 16:24:01 +0000 (UTC) Date: Sat, 13 Nov 2021 16:28:47 +0000 From: Jonathan Cameron To: Lars-Peter Clausen Cc: Michael Hennerich , Nuno Sa , Manuel Stahl , linux-iio@vger.kernel.org Subject: Re: [PATCH 2/2] iio: ad7768-1: Call iio_trigger_notify_done() on error Message-ID: <20211113162847.3f1eb11d@jic23-huawei> In-Reply-To: <20211101144055.13858-2-lars@metafoo.de> References: <20211101144055.13858-1-lars@metafoo.de> <20211101144055.13858-2-lars@metafoo.de> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Mon, 1 Nov 2021 15:40:55 +0100 Lars-Peter Clausen wrote: > IIO trigger handlers must call iio_trigger_notify_done() when done. This > must be done even when an error occurred. Otherwise the trigger will be > seen as busy indefinitely and the trigger handler will never be called > again. > > The ad7768-1 driver neglects to call iio_trigger_notify_done() when there > is an error reading the converter data. Fix this by making sure that > iio_trigger_notify_done() is included in the error exit path. > > Fixes: a5f8c7da3dbe ("iio: adc: Add AD7768-1 ADC basic support") > Signed-off-by: Lars-Peter Clausen Hi Lars, I've always meant to have a hard think about what we 'should' do in the event of an error in one of these trigger handlers. Definitely don't want to get stuck so these patches make sense, but I'd also at somepoint like to explore if we should stop the device capture and do something like poison the kfifo output so that we know it was broken. Anyhow, a discussion for another day. Applied these two to the fixes-togreg branch of iio.git and marked for stable. Thanks, Jonathan > --- > drivers/iio/adc/ad7768-1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c > index 2c5c8a3672b2..aa42ba759fa1 100644 > --- a/drivers/iio/adc/ad7768-1.c > +++ b/drivers/iio/adc/ad7768-1.c > @@ -480,8 +480,8 @@ static irqreturn_t ad7768_trigger_handler(int irq, void *p) > iio_push_to_buffers_with_timestamp(indio_dev, &st->data.scan, > iio_get_time_ns(indio_dev)); > > - iio_trigger_notify_done(indio_dev->trig); > err_unlock: > + iio_trigger_notify_done(indio_dev->trig); > mutex_unlock(&st->lock); > > return IRQ_HANDLED;