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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=unavailable 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 ABDA2C433E2 for ; Sun, 14 Jun 2020 12:13:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 781C62078A for ; Sun, 14 Jun 2020 12:13:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592136826; bh=Q5ykgQR1tu/wM3H9z7SgWdHDplTslPSXjz07ZPp0iLs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=M6g6Sj+w2pJVld0klL9ZVDuu6DQMQ01OBCaVgKGDXWMwWfsgPZBPaTyZ7gzgAA/VQ gc6xbmvgd3FPUCt5y3QaNhKMM2LoKDt+kjH0FtHnJXFYMgabGW2OycKhtg4ZfR6aef jWJQdw9o6UY59h2TaWSOM40/8O9qojyaGDEBpu10= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726859AbgFNMNn (ORCPT ); Sun, 14 Jun 2020 08:13:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:54066 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725815AbgFNMNm (ORCPT ); Sun, 14 Jun 2020 08:13:42 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (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 5B99920747; Sun, 14 Jun 2020 12:13:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592136819; bh=Q5ykgQR1tu/wM3H9z7SgWdHDplTslPSXjz07ZPp0iLs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OuCYcoyl+yRNqosL3iHQ0Od/WKExLKmvdYVBwWG6UmHSKe6l6qIKRSRs52FdO2G65 EtZbWMx0A/JBEyHVDypoflW5LQTByAQBJdEyRHXSJnHo7FfiQeUlXDjUfw6G2Quw1P /vVwk1MOkya4rwfNJRJmmivuXLzJ7f7ax/tiKX9k= Date: Sun, 14 Jun 2020 13:13:34 +0100 From: Jonathan Cameron To: Tomasz Duszynski Cc: , , , , , Subject: Re: [PATCH v4 1/4] iio: chemical: scd30: add core driver Message-ID: <20200614131334.63e65ac2@archlinux> In-Reply-To: <20200607115948.GA11496@arch> References: <20200603084441.33952-1-tomasz.duszynski@octakon.com> <20200603084441.33952-2-tomasz.duszynski@octakon.com> <20200606160652.4ea4cc15@archlinux> <20200607115948.GA11496@arch> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Sun, 7 Jun 2020 13:59:48 +0200 Tomasz Duszynski wrote: > On Sat, Jun 06, 2020 at 04:06:52PM +0100, Jonathan Cameron wrote: > > On Wed, 3 Jun 2020 10:44:38 +0200 > > Tomasz Duszynski wrote: > > > > > Add Sensirion SCD30 carbon dioxide core driver. > > > > > > Signed-off-by: Tomasz Duszynski > > > > Hi Tomasz, > > > > One trivial suggestion on loosening a little what counts > > as 'enabled' for the calibration enable. > > > > Otherwise, the ABI for providing the pressure seems odd > > (I missed this previously). It doesn't make sense to provide > > a calibscale for pressure. This is an actual pressure value. > > > > Hi Jonathan, > > Well it does make sense to some extent. If you dig into theory > behind compensation it turns out that you compensate co2 > measurement by scaling it by a reciprocal of a given pressure. Interesting. Kind of makes sense. > > So it seems to match calibscale definition except measured pressure > is not exposed to us directly. > > But if the output channel is preferred then fine. I think that would still be the best plan because a random user won't understand why it would be calibscale. They will think they are writing a 'value' of pressure rather than something to do with scale. Jonathan > > > What we have done for similar cases in the past is to take the > > slightly wide interpretation of output channels. In some sense > > this is about telling the sensor what the value 'should' be > > so I would just use an output pressure channel to provide this > > control. Its a bit odd, but without an explosion in complex > > channel descriptions we haven't come up with a better option yet. > > > > However its also weird enough I'd suggest taking the unusual > > step of documenting it even though it is sort of standard ABI. > > > > Fair enough. > > > Thanks, > > > > Jonathan > > > > > --- > > > Documentation/ABI/testing/sysfs-bus-iio-scd30 | 34 + > > > MAINTAINERS | 6 + > > > drivers/iio/chemical/Kconfig | 11 + > > > drivers/iio/chemical/Makefile | 1 + > > > drivers/iio/chemical/scd30.h | 78 ++ > > > drivers/iio/chemical/scd30_core.c | 761 ++++++++++++++++++ > > > 6 files changed, 891 insertions(+) > > > create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-scd30 > > > create mode 100644 drivers/iio/chemical/scd30.h > > > create mode 100644 drivers/iio/chemical/scd30_core.c > > > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-iio-scd30 b/Documentation/ABI/testing/sysfs-bus-iio-scd30 > > > new file mode 100644 > > > index 000000000000..b9712f390bec > > > --- /dev/null > > > +++ b/Documentation/ABI/testing/sysfs-bus-iio-scd30 > > > @@ -0,0 +1,34 @@ > > > +What: /sys/bus/iio/devices/iio:deviceX/calibration_auto_enable > > > +Date: June 2020 > > > +KernelVersion: 5.8 > > > +Contact: linux-iio@vger.kernel.org > > > +Description: > > > + Contaminants build-up in the measurement chamber or optical > > > + elements deterioration leads to sensor drift. > > > + > > > + One can compensate for sensor drift by using automatic self > > > + calibration procedure (asc). > > > + > > > + Writing 1 or 0 to this attribute will respectively activate or > > > + deactivate asc. > > > + > > > + Upon reading current asc status is returned. > > > + > > > +What: /sys/bus/iio/devices/iio:deviceX/calibration_forced_value > > > +Date: June 2020 > > > +KernelVersion: 5.8 > > > +Contact: linux-iio@vger.kernel.org > > > +Description: > > > + Contaminants build-up in the measurement chamber or optical > > > + elements deterioration leads to sensor drift. > > > + > > > + One can compensate for sensor drift by using forced > > > + recalibration (frc). This is useful in case there's known > > > + co2 reference available nearby the sensor. > > > + > > > + Picking value from the range [400 1 2000] and writing it to the > > > + sensor will set frc. > > > + > > > + Upon reading current frc value is returned. Note that after > > > + power cycling default value (i.e 400) is returned even though > > > + internally sensor had recalibrated itself. > > > diff --git a/MAINTAINERS b/MAINTAINERS > > > index 60ed2963efaa..41a509cca6f1 100644 > > > --- a/MAINTAINERS > > > +++ b/MAINTAINERS > > > @@ -15137,6 +15137,12 @@ S: Maintained > > > F: drivers/misc/phantom.c > > > F: include/uapi/linux/phantom.h > > > > > > +SENSIRION SCD30 CARBON DIOXIDE SENSOR DRIVER > > > +M: Tomasz Duszynski > > > +S: Maintained > > > +F: drivers/iio/chemical/scd30.h > > > +F: drivers/iio/chemical/scd30_core.c > > > + > > > SENSIRION SPS30 AIR POLLUTION SENSOR DRIVER > > > M: Tomasz Duszynski > > > S: Maintained > > > diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig > > > index 7f21afd73b1c..99e852b67e55 100644 > > > --- a/drivers/iio/chemical/Kconfig > > > +++ b/drivers/iio/chemical/Kconfig > > > @@ -85,6 +85,17 @@ config PMS7003 > > > To compile this driver as a module, choose M here: the module will > > > be called pms7003. > > > > > > +config SCD30_CORE > > > + tristate "SCD30 carbon dioxide sensor driver" > > > + select IIO_BUFFER > > > + select IIO_TRIGGERED_BUFFER > > > + help > > > + Say Y here to build support for the Sensirion SCD30 sensor with carbon > > > + dioxide, relative humidity and temperature sensing capabilities. > > > + > > > + To compile this driver as a module, choose M here: the module will > > > + be called scd30_core. > > > + > > > config SENSIRION_SGP30 > > > tristate "Sensirion SGPxx gas sensors" > > > depends on I2C > > > diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile > > > index aba4167db745..c9804b041ecd 100644 > > > --- a/drivers/iio/chemical/Makefile > > > +++ b/drivers/iio/chemical/Makefile > > > @@ -12,6 +12,7 @@ obj-$(CONFIG_BME680_SPI) += bme680_spi.o > > > obj-$(CONFIG_CCS811) += ccs811.o > > > obj-$(CONFIG_IAQCORE) += ams-iaq-core.o > > > obj-$(CONFIG_PMS7003) += pms7003.o > > > +obj-$(CONFIG_SCD30_CORE) += scd30_core.o > > > obj-$(CONFIG_SENSIRION_SGP30) += sgp30.o > > > obj-$(CONFIG_SPS30) += sps30.o > > > obj-$(CONFIG_VZ89X) += vz89x.o > > > diff --git a/drivers/iio/chemical/scd30.h b/drivers/iio/chemical/scd30.h > > > new file mode 100644 > > > index 000000000000..f60127bfe0f4 > > > --- /dev/null > > > +++ b/drivers/iio/chemical/scd30.h > > > @@ -0,0 +1,78 @@ > > > +/* SPDX-License-Identifier: GPL-2.0 */ > > > +#ifndef _SCD30_H > > > +#define _SCD30_H > > > + > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > + > > > +struct scd30_state; > > > + > > > +enum scd30_cmd { > > > + /* start continuous measurement with pressure compensation */ > > > + CMD_START_MEAS, > > > + /* stop continuous measurement */ > > > + CMD_STOP_MEAS, > > > + /* set/get measurement interval */ > > > + CMD_MEAS_INTERVAL, > > > + /* check whether new measurement is ready */ > > > + CMD_MEAS_READY, > > > + /* get measurement */ > > > + CMD_READ_MEAS, > > > + /* turn on/off automatic self calibration */ > > > + CMD_ASC, > > > + /* set/get forced recalibration value */ > > > + CMD_FRC, > > > + /* set/get temperature offset */ > > > + CMD_TEMP_OFFSET, > > > + /* get firmware version */ > > > + CMD_FW_VERSION, > > > + /* reset sensor */ > > > + CMD_RESET, > > > + /* > > > + * Command for altitude compensation was omitted intentionally because > > > + * the same can be achieved by means of CMD_START_MEAS which takes > > > + * pressure above the sea level as an argument. > > > + */ > > > +}; > > > + > > > +#define SCD30_MEAS_COUNT 3 > > > + > > > +typedef int (*scd30_command_t)(struct scd30_state *state, enum scd30_cmd cmd, u16 arg, > > > + void *response, int size); > > > + > > > +struct scd30_state { > > > + /* serialize access to the device */ > > > + struct mutex lock; > > > + struct device *dev; > > > + struct regulator *vdd; > > > + struct completion meas_ready; > > > + /* > > > + * priv pointer is solely for serdev driver private data. We keep it > > > + * here because driver_data inside dev has been already used for iio and > > > + * struct serdev_device doesn't have one. > > > + */ > > > + void *priv; > > > + int irq; > > > + /* > > > + * no way to retrieve current ambient pressure compensation value from > > > + * the sensor so keep one around > > > + */ > > > + u16 pressure_comp; > > > + u16 meas_interval; > > > + int meas[SCD30_MEAS_COUNT]; > > > + > > > + scd30_command_t command; > > > +}; > > > + > > > +int scd30_suspend(struct device *dev); > > > +int scd30_resume(struct device *dev); > > > + > > > +static __maybe_unused SIMPLE_DEV_PM_OPS(scd30_pm_ops, scd30_suspend, scd30_resume); > > > + > > > +int scd30_probe(struct device *dev, int irq, const char *name, void *priv, scd30_command_t command); > > > + > > > +#endif > > > diff --git a/drivers/iio/chemical/scd30_core.c b/drivers/iio/chemical/scd30_core.c > > > new file mode 100644 > > > index 000000000000..cf640a00f7ec > > > --- /dev/null > > > +++ b/drivers/iio/chemical/scd30_core.c > > > @@ -0,0 +1,761 @@ > > > +// SPDX-License-Identifier: GPL-2.0 > > > +/* > > > + * Sensirion SCD30 carbon dioxide sensor core driver > > > + * > > > + * Copyright (c) 2020 Tomasz Duszynski > > > + */ > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > + > > > +#include "scd30.h" > > > + > > > +#define SCD30_PRESSURE_COMP_MIN_MBAR 700 > > > +#define SCD30_PRESSURE_COMP_MAX_MBAR 1400 > > > +#define SCD30_PRESSURE_COMP_DEFAULT 1013 > > > +#define SCD30_MEAS_INTERVAL_MIN_S 2 > > > +#define SCD30_MEAS_INTERVAL_MAX_S 1800 > > > +#define SCD30_MEAS_INTERVAL_DEFAULT SCD30_MEAS_INTERVAL_MIN_S > > > +#define SCD30_FRC_MIN_PPM 400 > > > +#define SCD30_FRC_MAX_PPM 2000 > > > +#define SCD30_TEMP_OFFSET_MAX 655360 > > > +#define SCD30_EXTRA_TIMEOUT_PER_S 250 > > > + > > > +enum { > > > + SCD30_CONC, > > > + SCD30_TEMP, > > > + SCD30_HR, > > > +}; > > > + > > > +static int scd30_command_write(struct scd30_state *state, enum scd30_cmd cmd, u16 arg) > > > +{ > > > + return state->command(state, cmd, arg, NULL, 0); > > > +} > > > + > > > +static int scd30_command_read(struct scd30_state *state, enum scd30_cmd cmd, u16 *val) > > > +{ > > > + __be16 tmp; > > > + int ret; > > > + > > > + ret = state->command(state, cmd, 0, &tmp, sizeof(tmp)); > > > + *val = be16_to_cpup(&tmp); > > > + > > > + return ret; > > > +} > > > + > > > +static int scd30_reset(struct scd30_state *state) > > > +{ > > > + int ret; > > > + u16 val; > > > + > > > + ret = scd30_command_write(state, CMD_RESET, 0); > > > + if (ret) > > > + return ret; > > > + > > > + /* sensor boots up within 2 secs */ > > > + msleep(2000); > > > + /* > > > + * Power-on-reset causes sensor to produce some glitch on i2c bus and > > > + * some controllers end up in error state. Try to recover by placing > > > + * any data on the bus. > > > + */ > > > + scd30_command_read(state, CMD_MEAS_READY, &val); > > > + > > > + return 0; > > > +} > > > + > > > +/* simplified float to fixed point conversion with a scaling factor of 0.01 */ > > > +static int scd30_float_to_fp(int float32) > > > +{ > > > + int fraction, shift, > > > + mantissa = float32 & GENMASK(22, 0), > > > + sign = float32 & BIT(31) ? -1 : 1, > > > + exp = (float32 & ~BIT(31)) >> 23; > > > + > > > + /* special case 0 */ > > > + if (!exp && !mantissa) > > > + return 0; > > > + > > > + exp -= 127; > > > + if (exp < 0) { > > > + exp = -exp; > > > + /* return values ranging from 1 to 99 */ > > > + return sign * ((((BIT(23) + mantissa) * 100) >> 23) >> exp); > > > + } > > > + > > > + /* return values starting at 100 */ > > > + shift = 23 - exp; > > > + float32 = BIT(exp) + (mantissa >> shift); > > > + fraction = mantissa & GENMASK(shift - 1, 0); > > > + > > > + return sign * (float32 * 100 + ((fraction * 100) >> shift)); > > > +} > > > + > > > +static int scd30_read_meas(struct scd30_state *state) > > > +{ > > > + int i, ret; > > > + > > > + ret = state->command(state, CMD_READ_MEAS, 0, state->meas, sizeof(state->meas)); > > > + if (ret) > > > + return ret; > > > + > > > + be32_to_cpu_array(state->meas, state->meas, ARRAY_SIZE(state->meas)); > > > + > > > + for (i = 0; i < ARRAY_SIZE(state->meas); i++) > > > + state->meas[i] = scd30_float_to_fp(state->meas[i]); > > > + > > > + /* > > > + * co2 is left unprocessed while temperature and humidity are scaled > > > + * to milli deg C and milli percent respectively. > > > + */ > > > + state->meas[SCD30_TEMP] *= 10; > > > + state->meas[SCD30_HR] *= 10; > > > + > > > + return 0; > > > +} > > > + > > > +static int scd30_wait_meas_irq(struct scd30_state *state) > > > +{ > > > + int ret, timeout; > > > + > > > + reinit_completion(&state->meas_ready); > > > + enable_irq(state->irq); > > > + timeout = msecs_to_jiffies(state->meas_interval * (1000 + SCD30_EXTRA_TIMEOUT_PER_S)); > > > + ret = wait_for_completion_interruptible_timeout(&state->meas_ready, timeout); > > > + if (ret > 0) > > > + ret = 0; > > > + else if (!ret) > > > + ret = -ETIMEDOUT; > > > + > > > + disable_irq(state->irq); > > > + > > > + return ret; > > > +} > > > + > > > +static int scd30_wait_meas_poll(struct scd30_state *state) > > > +{ > > > + int timeout = state->meas_interval * SCD30_EXTRA_TIMEOUT_PER_S, tries = 5; > > > + > > > + do { > > > + int ret; > > > + u16 val; > > > + > > > + ret = scd30_command_read(state, CMD_MEAS_READY, &val); > > > + if (ret) > > > + return -EIO; > > > + > > > + /* new measurement available */ > > > + if (val) > > > + break; > > > + > > > + msleep_interruptible(timeout); > > > + } while (--tries); > > > + > > > + return tries ? 0 : -ETIMEDOUT; > > > +} > > > + > > > +static int scd30_read_poll(struct scd30_state *state) > > > +{ > > > + int ret; > > > + > > > + ret = scd30_wait_meas_poll(state); > > > + if (ret) > > > + return ret; > > > + > > > + return scd30_read_meas(state); > > > +} > > > + > > > +static int scd30_read(struct scd30_state *state) > > > +{ > > > + if (state->irq > 0) > > > + return scd30_wait_meas_irq(state); > > > + > > > + return scd30_read_poll(state); > > > +} > > > + > > > +static int scd30_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, > > > + int *val, int *val2, long mask) > > > +{ > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret = -EINVAL; > > > + u16 tmp; > > > + > > > + mutex_lock(&state->lock); > > > + switch (mask) { > > > + case IIO_CHAN_INFO_RAW: > > > + case IIO_CHAN_INFO_PROCESSED: > > > + ret = iio_device_claim_direct_mode(indio_dev); > > > + if (ret) > > > + break; > > > + > > > + ret = scd30_read(state); > > > + if (ret) { > > > + iio_device_release_direct_mode(indio_dev); > > > + break; > > > + } > > > + > > > + *val = state->meas[chan->address]; > > > + iio_device_release_direct_mode(indio_dev); > > > + ret = IIO_VAL_INT; > > > + break; > > > + case IIO_CHAN_INFO_SCALE: > > > + *val = 0; > > > + *val2 = 1; > > > + ret = IIO_VAL_INT_PLUS_MICRO; > > > + break; > > > + case IIO_CHAN_INFO_SAMP_FREQ: > > > + ret = scd30_command_read(state, CMD_MEAS_INTERVAL, &tmp); > > > + if (ret) > > > + break; > > > + > > > + *val = 0; > > > + *val2 = 1000000000 / tmp; > > > + ret = IIO_VAL_INT_PLUS_NANO; > > > + break; > > > + case IIO_CHAN_INFO_CALIBSCALE: > > > + *val = state->pressure_comp / 10; > > > + *val2 = (state->pressure_comp % 10) * 100000; > > > + ret = IIO_VAL_INT_PLUS_MICRO; > > > + break; > > > + case IIO_CHAN_INFO_CALIBBIAS: > > > + ret = scd30_command_read(state, CMD_TEMP_OFFSET, &tmp); > > > + if (ret) > > > + break; > > > + > > > + *val = tmp; > > > + ret = IIO_VAL_INT; > > > + break; > > > + } > > > + mutex_unlock(&state->lock); > > > + > > > + return ret; > > > +} > > > + > > > +static int scd30_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, > > > + int val, int val2, long mask) > > > +{ > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret = -EINVAL; > > > + > > > + mutex_lock(&state->lock); > > > + switch (mask) { > > > + case IIO_CHAN_INFO_SAMP_FREQ: > > > + if (val) > > > + break; > > > + > > > + val = 1000000000 / val2; > > > + if (val < SCD30_MEAS_INTERVAL_MIN_S || val > SCD30_MEAS_INTERVAL_MAX_S) > > > + break; > > > + > > > + ret = scd30_command_write(state, CMD_MEAS_INTERVAL, val); > > > + if (ret) > > > + break; > > > + > > > + state->meas_interval = val; > > > + break; > > > + case IIO_CHAN_INFO_CALIBSCALE: > > > + val = (val * 1000000 + val2) / 100000; > > > + if (val < SCD30_PRESSURE_COMP_MIN_MBAR || val > SCD30_PRESSURE_COMP_MAX_MBAR) > > > + break; > > > + > > > + ret = scd30_command_write(state, CMD_START_MEAS, val); > > > + if (ret) > > > + break; > > > + > > > + state->pressure_comp = val; > > > + break; > > > + case IIO_CHAN_INFO_CALIBBIAS: > > > + if (val < 0 || val > SCD30_TEMP_OFFSET_MAX) > > > + break; > > > + /* > > > + * Manufacturer does not explicitly specify min/max sensible > > > + * values hence check is omitted for simplicity. > > > + */ > > > + ret = scd30_command_write(state, CMD_TEMP_OFFSET / 10, val); > > > + } > > > + mutex_unlock(&state->lock); > > > + > > > + return ret; > > > +} > > > + > > > +static int scd30_write_raw_get_fmt(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, > > > + long mask) > > > +{ > > > + switch (mask) { > > > + case IIO_CHAN_INFO_SAMP_FREQ: > > > + return IIO_VAL_INT_PLUS_NANO; > > > + case IIO_CHAN_INFO_CALIBSCALE: > > > + return IIO_VAL_INT_PLUS_MICRO; > > > + case IIO_CHAN_INFO_CALIBBIAS: > > > + return IIO_VAL_INT; > > > + } > > > + > > > + return -EINVAL; > > > +} > > > + > > > +static const int scd30_pressure_calibscale_available[] = { > > > + SCD30_PRESSURE_COMP_MIN_MBAR / 10, 0, > > > + 0, 100000, > > > + SCD30_PRESSURE_COMP_MAX_MBAR / 10, 0, > > > +}; > > > + > > > +static const int scd30_temp_calibbias_available[] = { > > > + 0, 10, SCD30_TEMP_OFFSET_MAX, > > > +}; > > > + > > > +static int scd30_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, > > > + const int **vals, int *type, int *length, long mask) > > > +{ > > > + switch (mask) { > > > + case IIO_CHAN_INFO_CALIBSCALE: > > > + *vals = scd30_pressure_calibscale_available; > > > + *type = IIO_VAL_INT_PLUS_MICRO; > > > + > > > + return IIO_AVAIL_RANGE; > > > + case IIO_CHAN_INFO_CALIBBIAS: > > > + *vals = scd30_temp_calibbias_available; > > > + *type = IIO_VAL_INT; > > > + > > > + return IIO_AVAIL_RANGE; > > > + } > > > + > > > + return -EINVAL; > > > +} > > > + > > > +static ssize_t sampling_frequency_available_show(struct device *dev, struct device_attribute *attr, > > > + char *buf) > > > +{ > > > + int i = SCD30_MEAS_INTERVAL_MIN_S; > > > + ssize_t len = 0; > > > + > > > + do { > > > + len += scnprintf(buf + len, PAGE_SIZE - len, "0.%09u ", 1000000000 / i); > > > + /* > > > + * Not all values fit PAGE_SIZE buffer hence print every 6th > > > + * (each frequency differs by 6s in time domain from the > > > + * adjacent). Unlisted but valid ones are still accepted. > > > + */ > > > + i += 6; > > > + } while (i <= SCD30_MEAS_INTERVAL_MAX_S); > > > + > > > + buf[len - 1] = '\n'; > > > + > > > + return len; > > > +} > > > + > > > +static ssize_t calibration_auto_enable_show(struct device *dev, struct device_attribute *attr, > > > + char *buf) > > > +{ > > > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + u16 val; > > > + > > > + mutex_lock(&state->lock); > > > + ret = scd30_command_read(state, CMD_ASC, &val); > > > + mutex_unlock(&state->lock); > > > + > > > + return ret ?: sprintf(buf, "%d\n", val); > > > +} > > > + > > > +static ssize_t calibration_auto_enable_store(struct device *dev, struct device_attribute *attr, > > > + const char *buf, size_t len) > > > +{ > > > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + u16 val; > > > + > > > + ret = kstrtou16(buf, 0, &val); > > > > For enable controls like this we have a magic kstrtobool which > > is a bit more flexible in what it allows > > > > https://elixir.bootlin.com/linux/latest/source/lib/kstrtox.c#L332 > > > > Matter of preference I guess, but okay. > > > > + if (ret) > > > + return ret; > > > + > > > + mutex_lock(&state->lock); > > > + ret = scd30_command_write(state, CMD_ASC, !!val); > > > + mutex_unlock(&state->lock); > > > + > > > + return ret ?: len; > > > +} > > > + > > > +static ssize_t calibration_forced_value_show(struct device *dev, struct device_attribute *attr, > > > + char *buf) > > > +{ > > > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + u16 val; > > > + > > > + mutex_lock(&state->lock); > > > + ret = scd30_command_read(state, CMD_FRC, &val); > > > + mutex_unlock(&state->lock); > > > + > > > + return ret ?: sprintf(buf, "%d\n", val); > > > +} > > > + > > > +static ssize_t calibration_forced_value_store(struct device *dev, struct device_attribute *attr, > > > + const char *buf, size_t len) > > > +{ > > > + struct iio_dev *indio_dev = dev_to_iio_dev(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + u16 val; > > > + > > > + ret = kstrtou16(buf, 0, &val); > > > + if (ret) > > > + return ret; > > > + > > > + if (val < SCD30_FRC_MIN_PPM || val > SCD30_FRC_MAX_PPM) > > > + return -EINVAL; > > > + > > > + mutex_lock(&state->lock); > > > + ret = scd30_command_write(state, CMD_FRC, val); > > > + mutex_unlock(&state->lock); > > > + > > > + return ret ?: len; > > > +} > > > + > > > +static IIO_DEVICE_ATTR_RO(sampling_frequency_available, 0); > > > +static IIO_DEVICE_ATTR_RW(calibration_auto_enable, 0); > > > +static IIO_DEVICE_ATTR_RW(calibration_forced_value, 0); > > > + > > > +static struct attribute *scd30_attrs[] = { > > > + &iio_dev_attr_sampling_frequency_available.dev_attr.attr, > > > + &iio_dev_attr_calibration_auto_enable.dev_attr.attr, > > > + &iio_dev_attr_calibration_forced_value.dev_attr.attr, > > > + NULL > > > +}; > > > + > > > +static const struct attribute_group scd30_attr_group = { > > > + .attrs = scd30_attrs, > > > +}; > > > + > > > +static const struct iio_info scd30_info = { > > > + .attrs = &scd30_attr_group, > > > + .read_raw = scd30_read_raw, > > > + .write_raw = scd30_write_raw, > > > + .write_raw_get_fmt = scd30_write_raw_get_fmt, > > > + .read_avail = scd30_read_avail, > > > +}; > > > + > > > +#define SCD30_CHAN_SCAN_TYPE(_sign, _realbits) .scan_type = { \ > > > + .sign = _sign, \ > > > + .realbits = _realbits, \ > > > + .storagebits = 32, \ > > > + .endianness = IIO_CPU, \ > > > +} > > > + > > > +static const struct iio_chan_spec scd30_channels[] = { > > > + { > > > + .type = IIO_PRESSURE, > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBSCALE), > > > + .info_mask_separate_available = BIT(IIO_CHAN_INFO_CALIBSCALE), > > > > I missed this before, but using pressure calib scale to allow you input the > > current pressure in millibar seems odd... > > > > Unit is kPa actually. > > > For similar cases we've use a magic output channel and just used > > the raw attr to provide the control. In some sense we are setting > > the sensors idea of what the value is (obviously it doesn't then > > actually change the pressure).. > > > > Even with this it's also odd enough I'd suggest documenting this particular > > bit of ABI. > > > > > + .scan_index = -1, > > > + }, > > > + { > > > + .type = IIO_CONCENTRATION, > > > + .channel2 = IIO_MOD_CO2, > > > + .address = SCD30_CONC, > > > + .scan_index = SCD30_CONC, > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > > > + BIT(IIO_CHAN_INFO_SCALE), > > > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), > > > + .modified = 1, > > > + > > > + SCD30_CHAN_SCAN_TYPE('u', 20), > > > + }, > > > + { > > > + .type = IIO_TEMP, > > > + .address = SCD30_TEMP, > > > + .scan_index = SCD30_TEMP, > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | > > > + BIT(IIO_CHAN_INFO_CALIBBIAS), > > > + .info_mask_separate_available = BIT(IIO_CHAN_INFO_CALIBBIAS), > > > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), > > > + > > > + SCD30_CHAN_SCAN_TYPE('s', 18), > > > + }, > > > + { > > > + .type = IIO_HUMIDITYRELATIVE, > > > + .address = SCD30_HR, > > > + .scan_index = SCD30_HR, > > > + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), > > > + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), > > > + > > > + SCD30_CHAN_SCAN_TYPE('u', 17), > > > + }, > > > + IIO_CHAN_SOFT_TIMESTAMP(3), > > > +}; > > > + > > > +int __maybe_unused scd30_suspend(struct device *dev) > > > +{ > > > + struct iio_dev *indio_dev = dev_get_drvdata(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + > > > + ret = scd30_command_write(state, CMD_STOP_MEAS, 0); > > > + if (ret) > > > + return ret; > > > + > > > + return regulator_disable(state->vdd); > > > +} > > > +EXPORT_SYMBOL(scd30_suspend); > > > + > > > +int __maybe_unused scd30_resume(struct device *dev) > > > +{ > > > + struct iio_dev *indio_dev = dev_get_drvdata(dev); > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + > > > + ret = regulator_enable(state->vdd); > > > + if (ret) > > > + return ret; > > > + > > > + return scd30_command_write(state, CMD_START_MEAS, state->pressure_comp); > > > +} > > > +EXPORT_SYMBOL(scd30_resume); > > > + > > > +static void scd30_stop_meas(void *data) > > > +{ > > > + struct scd30_state *state = data; > > > + > > > + scd30_command_write(state, CMD_STOP_MEAS, 0); > > > +} > > > + > > > +static void scd30_disable_regulator(void *data) > > > +{ > > > + struct scd30_state *state = data; > > > + > > > + regulator_disable(state->vdd); > > > +} > > > + > > > +static irqreturn_t scd30_irq_handler(int irq, void *priv) > > > +{ > > > + struct iio_dev *indio_dev = priv; > > > + > > > + if (iio_buffer_enabled(indio_dev)) { > > > + iio_trigger_poll(indio_dev->trig); > > > + > > > + return IRQ_HANDLED; > > > + } > > > + > > > + return IRQ_WAKE_THREAD; > > > +} > > > + > > > +static irqreturn_t scd30_irq_thread_handler(int irq, void *priv) > > > +{ > > > + struct iio_dev *indio_dev = priv; > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + int ret; > > > + > > > + ret = scd30_read_meas(state); > > > + if (ret) > > > + goto out; > > > + > > > + complete_all(&state->meas_ready); > > > +out: > > > + return IRQ_HANDLED; > > > +} > > > + > > > +static irqreturn_t scd30_trigger_handler(int irq, void *p) > > > +{ > > > + struct iio_poll_func *pf = p; > > > + struct iio_dev *indio_dev = pf->indio_dev; > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + struct { > > > + int data[SCD30_MEAS_COUNT]; > > > + s64 ts __aligned(8); > > > + } scan = { 0, }; > > > + int ret; > > > + > > > + mutex_lock(&state->lock); > > > + if (!iio_trigger_using_own(indio_dev)) > > > + ret = scd30_read_poll(state); > > > + else > > > + ret = scd30_read_meas(state); > > > + memcpy(scan.data, state->meas, sizeof(state->meas)); > > > + mutex_unlock(&state->lock); > > > + if (ret) > > > + goto out; > > > + > > > + iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev)); > > > +out: > > > + iio_trigger_notify_done(indio_dev->trig); > > > + return IRQ_HANDLED; > > > +} > > > + > > > +static int scd30_set_trigger_state(struct iio_trigger *trig, bool state) > > > +{ > > > + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); > > > + struct scd30_state *st = iio_priv(indio_dev); > > > + > > > + if (state) > > > + enable_irq(st->irq); > > > + else > > > + disable_irq(st->irq); > > > + > > > + return 0; > > > +} > > > + > > > +static const struct iio_trigger_ops scd30_trigger_ops = { > > > + .set_trigger_state = scd30_set_trigger_state, > > > + .validate_device = iio_trigger_validate_own_device, > > > +}; > > > + > > > +static int scd30_setup_trigger(struct iio_dev *indio_dev) > > > +{ > > > + struct scd30_state *state = iio_priv(indio_dev); > > > + struct device *dev = indio_dev->dev.parent; > > > + struct iio_trigger *trig; > > > + int ret; > > > + > > > + trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, indio_dev->id); > > > + if (!trig) { > > > + dev_err(dev, "failed to allocate trigger\n"); > > > + return -ENOMEM; > > > + } > > > + > > > + trig->dev.parent = dev; > > > + trig->ops = &scd30_trigger_ops; > > > + iio_trigger_set_drvdata(trig, indio_dev); > > > + > > > + ret = devm_iio_trigger_register(dev, trig); > > > + if (ret) > > > + return ret; > > > + > > > + indio_dev->trig = iio_trigger_get(trig); > > > + > > > + ret = devm_request_threaded_irq(dev, state->irq, scd30_irq_handler, > > > + scd30_irq_thread_handler, IRQF_TRIGGER_HIGH | IRQF_ONESHOT, > > > + indio_dev->name, indio_dev); > > > + if (ret) > > > + dev_err(dev, "failed to request irq\n"); > > > + > > > + /* > > > + * Interrupt is enabled just before taking a fresh measurement > > > + * and disabled afterwards. This means we need to disable it here > > > + * to keep calls to enable/disable balanced. > > > + */ > > > + disable_irq(state->irq); > > > + > > > + return ret; > > > +} > > > + > > > +int scd30_probe(struct device *dev, int irq, const char *name, void *priv, > > > + scd30_command_t command) > > > +{ > > > + static const unsigned long scd30_scan_masks[] = { 0x07, 0x00 }; > > > + struct scd30_state *state; > > > + struct iio_dev *indio_dev; > > > + int ret; > > > + u16 val; > > > + > > > + indio_dev = devm_iio_device_alloc(dev, sizeof(*state)); > > > + if (!indio_dev) > > > + return -ENOMEM; > > > + > > > + state = iio_priv(indio_dev); > > > + state->dev = dev; > > > + state->priv = priv; > > > + state->irq = irq; > > > + state->pressure_comp = SCD30_PRESSURE_COMP_DEFAULT; > > > + state->meas_interval = SCD30_MEAS_INTERVAL_DEFAULT; > > > + state->command = command; > > > + mutex_init(&state->lock); > > > + init_completion(&state->meas_ready); > > > + > > > + dev_set_drvdata(dev, indio_dev); > > > + > > > + indio_dev->dev.parent = dev; > > > + indio_dev->info = &scd30_info; > > > + indio_dev->name = name; > > > + indio_dev->channels = scd30_channels; > > > + indio_dev->num_channels = ARRAY_SIZE(scd30_channels); > > > + indio_dev->modes = INDIO_DIRECT_MODE; > > > + indio_dev->available_scan_masks = scd30_scan_masks; > > > + > > > + state->vdd = devm_regulator_get(dev, "vdd"); > > > + if (IS_ERR(state->vdd)) { > > > + if (PTR_ERR(state->vdd) == -EPROBE_DEFER) > > > + return -EPROBE_DEFER; > > > + > > > + dev_err(dev, "failed to get regulator\n"); > > > + return PTR_ERR(state->vdd); > > > + } > > > + > > > + ret = regulator_enable(state->vdd); > > > + if (ret) > > > + return ret; > > > + > > > + ret = devm_add_action_or_reset(dev, scd30_disable_regulator, state); > > > + if (ret) > > > + return ret; > > > + > > > + ret = scd30_reset(state); > > > + if (ret) { > > > + dev_err(dev, "failed to reset device: %d\n", ret); > > > + return ret; > > > + } > > > + > > > + if (state->irq > 0) { > > > + ret = scd30_setup_trigger(indio_dev); > > > + if (ret) { > > > + dev_err(dev, "failed to setup trigger: %d\n", ret); > > > + return ret; > > > + } > > > + } > > > + > > > + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd30_trigger_handler, NULL); > > > + if (ret) > > > + return ret; > > > + > > > + ret = scd30_command_read(state, CMD_FW_VERSION, &val); > > > + if (ret) { > > > + dev_err(dev, "failed to read firmware version: %d\n", ret); > > > + return ret; > > > + } > > > + dev_info(dev, "firmware version: %d.%d\n", val >> 8, (char)val); > > > + > > > + ret = scd30_command_write(state, CMD_MEAS_INTERVAL, state->meas_interval); > > > + if (ret) { > > > + dev_err(dev, "failed to set measurement interval: %d\n", ret); > > > + return ret; > > > + } > > > + > > > + ret = scd30_command_write(state, CMD_START_MEAS, state->pressure_comp); > > > + if (ret) { > > > + dev_err(dev, "failed to start measurement: %d\n", ret); > > > + return ret; > > > + } > > > + > > > + ret = devm_add_action_or_reset(dev, scd30_stop_meas, state); > > > + if (ret) > > > + return ret; > > > + > > > + return devm_iio_device_register(dev, indio_dev); > > > +} > > > +EXPORT_SYMBOL(scd30_probe); > > > + > > > +MODULE_AUTHOR("Tomasz Duszynski "); > > > +MODULE_DESCRIPTION("Sensirion SCD30 carbon dioxide sensor core driver"); > > > +MODULE_LICENSE("GPL v2"); > >