From nobody Sun Feb 8 15:08:09 2026 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 C9610EB64DD for ; Tue, 4 Jul 2023 09:04:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231555AbjGDJEd (ORCPT ); Tue, 4 Jul 2023 05:04:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229598AbjGDJEb (ORCPT ); Tue, 4 Jul 2023 05:04:31 -0400 X-Greylist: delayed 963 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 04 Jul 2023 02:04:26 PDT Received: from smtp15.bhosted.nl (smtp15.bhosted.nl [IPv6:2a02:9e0:8000::26]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0E7A1A2 for ; Tue, 4 Jul 2023 02:04:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonic.nl; s=202111; h=content-transfer-encoding:mime-version:message-id:date:subject:cc:to:from: from; bh=ycfj2BCIyCgA8eLgIbquApDUyZU7DdA5ZV0cKZoxzg0=; b=SCuyFuvkuMBhO+TsaInCcf3f8BWugJAbXBCkSCbogZNtcMkJSn4pF/QKd2BDtaMweV2a0Hm/f6zpz f4AOoUnIlzhegCeadUgS33N+eC5KwhCcXTPvdouvnlQkVIT0AuoKBh7gQwr8eb0CdrJ4L8+XffO/D8 srJXxvfvam2XMX4fvJc/dDDqiaWQXAItEQSPuPx1kAHC3935asTr4wC4OyIwd5CyPHrr5sa+44/rSp UfjxmnfxkH+6iJ21SG5SzahvwvodFb+PFagxPUvJC1/bK23UibSJ5LZMhlne4NgMXQFbVECJ3qrzXZ /h6HT0xXVYA2/xjwMH6THK4AMmirlYw== X-MSG-ID: 86e0501c-1a47-11ee-a4fd-0050569d3a82 From: Roan van Dijk To: jic23@kernel.org Cc: lars@metafoo.de, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, roan@protonic.nl Subject: [PATCH] iio: chemical: scd4x: Add pressure compensation Date: Tue, 4 Jul 2023 10:47:06 +0200 Message-Id: <20230704084706.370637-1-roan@protonic.nl> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This patch adds pressure compensation to the scd4x driver. The pressure can be written to the sensor in hPa. The pressure will be compensated internally by the sensor. Signed-off-by: Roan van Dijk --- drivers/iio/chemical/scd4x.c | 41 +++++++++++++++++++++++++++++++++--- 1 file changed, 38 insertions(+), 3 deletions(-) diff --git a/drivers/iio/chemical/scd4x.c b/drivers/iio/chemical/scd4x.c index a4f22d926400..fe6b3f3f7186 100644 --- a/drivers/iio/chemical/scd4x.c +++ b/drivers/iio/chemical/scd4x.c @@ -36,6 +36,8 @@ #define SCD4X_WRITE_BUF_SIZE 5 #define SCD4X_FRC_MIN_PPM 0 #define SCD4X_FRC_MAX_PPM 2000 +#define SCD4X_AMB_PRESSURE_MIN 700 +#define SCD4X_AMB_PRESSURE_MAX 1200 #define SCD4X_READY_MASK 0x01 =20 /*Commands SCD4X*/ @@ -45,6 +47,8 @@ enum scd4x_cmd { CMD_STOP_MEAS =3D 0x3f86, CMD_SET_TEMP_OFFSET =3D 0x241d, CMD_GET_TEMP_OFFSET =3D 0x2318, + CMD_SET_AMB_PRESSURE =3D 0xe000, + CMD_GET_AMB_PRESSURE =3D 0xe000, CMD_FRC =3D 0x362f, CMD_SET_ASC =3D 0x2416, CMD_GET_ASC =3D 0x2313, @@ -373,7 +377,10 @@ static int scd4x_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_CALIBBIAS: mutex_lock(&state->lock); - ret =3D scd4x_read(state, CMD_GET_TEMP_OFFSET, &tmp, sizeof(tmp)); + if (chan->type =3D=3D IIO_TEMP) + ret =3D scd4x_read(state, CMD_GET_TEMP_OFFSET, &tmp, sizeof(tmp)); + else if (chan->type =3D=3D IIO_PRESSURE) + ret =3D scd4x_read(state, CMD_GET_AMB_PRESSURE, &tmp, sizeof(tmp)); mutex_unlock(&state->lock); if (ret) return ret; @@ -386,6 +393,25 @@ static int scd4x_read_raw(struct iio_dev *indio_dev, } } =20 +static const int scd4x_pressure_calibbias_available[] =3D { + SCD4X_AMB_PRESSURE_MIN, 1, SCD4X_AMB_PRESSURE_MAX, +}; + +static int scd4x_read_avail(struct iio_dev *indio_dev, struct iio_chan_spe= c const *chan, + const int **vals, int *type, int *length, long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_CALIBBIAS: + *vals =3D scd4x_pressure_calibbias_available; + *type =3D IIO_VAL_INT; + + return IIO_AVAIL_RANGE; + } + + return -EINVAL; +} + + static int scd4x_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec= const *chan, int val, int val2, long mask) { @@ -395,9 +421,11 @@ static int scd4x_write_raw(struct iio_dev *indio_dev, = struct iio_chan_spec const switch (mask) { case IIO_CHAN_INFO_CALIBBIAS: mutex_lock(&state->lock); - ret =3D scd4x_write(state, CMD_SET_TEMP_OFFSET, val); + if (chan->type =3D=3D IIO_TEMP) + ret =3D scd4x_write(state, CMD_SET_TEMP_OFFSET, val); + else if (chan->type =3D=3D IIO_PRESSURE) + ret =3D scd4x_write(state, CMD_SET_AMB_PRESSURE, val); mutex_unlock(&state->lock); - return ret; default: return -EINVAL; @@ -503,9 +531,16 @@ static const struct iio_info scd4x_info =3D { .attrs =3D &scd4x_attr_group, .read_raw =3D scd4x_read_raw, .write_raw =3D scd4x_write_raw, + .read_avail =3D scd4x_read_avail, }; =20 static const struct iio_chan_spec scd4x_channels[] =3D { + { + .type =3D IIO_PRESSURE, + .info_mask_separate =3D BIT(IIO_CHAN_INFO_CALIBBIAS), + .info_mask_separate_available =3D BIT(IIO_CHAN_INFO_CALIBBIAS), + .scan_index =3D -1, + }, { .type =3D IIO_CONCENTRATION, .channel2 =3D IIO_MOD_CO2, --=20 2.39.2