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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E646C77B7C for ; Sun, 28 May 2023 17:16:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229580AbjE1RQ6 (ORCPT ); Sun, 28 May 2023 13:16:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229448AbjE1RQ5 (ORCPT ); Sun, 28 May 2023 13:16:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 449F1B1; Sun, 28 May 2023 10:16:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D4C4360D41; Sun, 28 May 2023 17:16:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8EB12C433EF; Sun, 28 May 2023 17:16:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685294215; bh=YjPMJglYziMf65WnCe3v/F6xmPWGu2CM6tFPiWOwMdM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=EKRLHW3q/j9L49ezWa6jrqYs14FpKHUBwPyZR/0vr9g0xC2PS+r663M0BjwzdIiUG mtB0+6N3uHaTPuLVX0KLveNcBkkIxQn9GGqamqu34zGFbl8tTue8iGbVWZEwLbz1Lz NSyF4joAxDpoWYmPEe9s95NKrZMwMFteLm3uMMGnL30+fa1zV4eRgkUWRv95HCMqFb CE7A/OMeHuOW2wxGUpSjcaIF+DMwL/i29Q7y/2fkozA2yYSV99JO5BbY6a1FrYiBK6 3BqIUtTKlI5lczrfW6ghM+m1E8U1t37E7tJUFCOGB4ithC4bW8XAwz4TixEfTd+zVR 2er2nkabmHjQw== Date: Sun, 28 May 2023 18:33:13 +0100 From: Jonathan Cameron To: Herve Codina Cc: Liam Girdwood , Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Lars-Peter Clausen , Jaroslav Kysela , Takashi Iwai , Kuninori Morimoto , alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Christophe Leroy , Thomas Petazzoni Subject: Re: [PATCH v2 5/9] iio: inkern: Add a helper to query an available minimum raw value Message-ID: <20230528183313.44d7cbf5@jic23-huawei> In-Reply-To: <20230523151223.109551-6-herve.codina@bootlin.com> References: <20230523151223.109551-1-herve.codina@bootlin.com> <20230523151223.109551-6-herve.codina@bootlin.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; 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: devicetree@vger.kernel.org On Tue, 23 May 2023 17:12:19 +0200 Herve Codina wrote: > A helper, iio_read_max_channel_raw() exists to read the available > maximum raw value of a channel but nothing similar exists to read the > available minimum raw value. > > This new helper, iio_read_min_channel_raw(), fills the hole and can be > used for reading the available minimum raw value of a channel. > It is fully based on the existing iio_read_max_channel_raw(). > > Signed-off-by: Herve Codina Acked-by: Jonathan Cameron > --- > drivers/iio/inkern.c | 70 ++++++++++++++++++++++++++++++++++++ > include/linux/iio/consumer.h | 12 +++++++ > 2 files changed, 82 insertions(+) > > diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c > index f738db9a0c04..07b26ff8a334 100644 > --- a/drivers/iio/inkern.c > +++ b/drivers/iio/inkern.c > @@ -915,6 +915,76 @@ int iio_read_max_channel_raw(struct iio_channel *chan, int *val) > } > EXPORT_SYMBOL_GPL(iio_read_max_channel_raw); > > +static int iio_channel_read_min(struct iio_channel *chan, > + int *val, int *val2, int *type, > + enum iio_chan_info_enum info) > +{ > + int unused; > + const int *vals; > + int length; > + int ret; > + > + if (!val2) > + val2 = &unused; > + > + ret = iio_channel_read_avail(chan, &vals, type, &length, info); > + if (ret < 0) > + return ret; > + > + switch (ret) { > + case IIO_AVAIL_RANGE: > + switch (*type) { > + case IIO_VAL_INT: > + *val = vals[0]; > + break; > + default: > + *val = vals[0]; > + *val2 = vals[1]; > + } > + return 0; > + > + case IIO_AVAIL_LIST: > + if (length <= 0) > + return -EINVAL; > + switch (*type) { > + case IIO_VAL_INT: > + *val = vals[--length]; > + while (length) { > + if (vals[--length] < *val) > + *val = vals[length]; > + } > + break; > + default: > + /* FIXME: learn about min for other iio values */ > + return -EINVAL; > + } > + return 0; > + > + default: > + return -EINVAL; > + } > +} > + > +int iio_read_min_channel_raw(struct iio_channel *chan, int *val) > +{ > + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev); > + int ret; > + int type; > + > + mutex_lock(&iio_dev_opaque->info_exist_lock); > + if (!chan->indio_dev->info) { > + ret = -ENODEV; > + goto err_unlock; > + } > + > + ret = iio_channel_read_min(chan, val, NULL, &type, IIO_CHAN_INFO_RAW); > +err_unlock: > + mutex_unlock(&iio_dev_opaque->info_exist_lock); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(iio_read_min_channel_raw); > + > int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type) > { > struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev); > diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h > index f536820b9cf2..e9910b41d48e 100644 > --- a/include/linux/iio/consumer.h > +++ b/include/linux/iio/consumer.h > @@ -301,6 +301,18 @@ int iio_write_channel_raw(struct iio_channel *chan, int val); > */ > int iio_read_max_channel_raw(struct iio_channel *chan, int *val); > > +/** > + * iio_read_min_channel_raw() - read minimum available raw value from a given > + * channel, i.e. the minimum possible value. > + * @chan: The channel being queried. > + * @val: Value read back. > + * > + * Note, if standard units are required, raw reads from iio channels > + * need the offset (default 0) and scale (default 1) to be applied > + * as (raw + offset) * scale. > + */ > +int iio_read_min_channel_raw(struct iio_channel *chan, int *val); > + > /** > * iio_read_avail_channel_raw() - read available raw values from a given channel > * @chan: The channel being queried.