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authorPetr Štetiar <ynezz@true.cz>2020-02-23 22:50:22 +0100
committerPetr Štetiar <ynezz@true.cz>2020-03-08 15:10:55 +0100
commitaae4d85647f27ca64d2012501636e41d5a8ab42a (patch)
treee49c8d7e536d23d510bd121e532e57eb4a4116ef /target/linux
parentea1823a8673a3f10aca418ca64b765f5c5a6e58f (diff)
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kernel: add kernel module for Sensirion SPS30 PMS
Adds into 4.19 backported kernel module from 5.1 for Sensirion SPS30 particulate matter sensor, for kernel 5.4 backported dependency fix. Signed-off-by: Petr Štetiar <ynezz@true.cz>
Diffstat (limited to 'target/linux')
-rw-r--r--target/linux/generic/backport-4.19/499-v4.22-iio-add-IIO_MASSCONCENTRATION-channel-type.patch144
-rw-r--r--target/linux/generic/backport-4.19/500-v5.1-iio-chemical-add-support-for-Sensirion-SPS30-sensor.patch461
-rw-r--r--target/linux/generic/backport-4.19/501-v5.1-iio-chemical-sps30-add-support-for-self-cleaning.patch105
-rw-r--r--target/linux/generic/backport-4.19/502-v5.1-iio-chemical-sps30-allow-changing-self-cleaning-peri.patch297
-rw-r--r--target/linux/generic/backport-4.19/503-v5.1-iio-chemical-sps30-remove-printk-format-specifier.patch27
-rw-r--r--target/linux/generic/backport-4.19/504-v5.1-iio-chemical-sps30-fix-a-loop-timeout-test.patch28
-rw-r--r--target/linux/generic/backport-4.19/505-v5.1-iio-chemical-sps30-Supress-some-switch-fallthrough-w.patch36
-rw-r--r--target/linux/generic/backport-4.19/506-v5.1-iio-chemical-sps30-Explicity-truncate-constant-by-ma.patch33
-rw-r--r--target/linux/generic/backport-4.19/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch32
-rw-r--r--target/linux/generic/backport-5.4/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch32
10 files changed, 1195 insertions, 0 deletions
diff --git a/target/linux/generic/backport-4.19/499-v4.22-iio-add-IIO_MASSCONCENTRATION-channel-type.patch b/target/linux/generic/backport-4.19/499-v4.22-iio-add-IIO_MASSCONCENTRATION-channel-type.patch
new file mode 100644
index 0000000000..c214495f03
--- /dev/null
+++ b/target/linux/generic/backport-4.19/499-v4.22-iio-add-IIO_MASSCONCENTRATION-channel-type.patch
@@ -0,0 +1,144 @@
+From 17abc9ec68b73ddeb262a507a62421016b9c54d5 Mon Sep 17 00:00:00 2001
+From: Tomasz Duszynski <tduszyns@gmail.com>
+Date: Fri, 14 Dec 2018 19:28:01 +0100
+Subject: [PATCH] iio: add IIO_MASSCONCENTRATION channel type
+
+Measuring particulate matter in ug / m3 (micro-grams per cubic meter)
+is de facto standard. Existing air quality sensors usually follow
+this convention and are capable of returning measurements using
+this unit.
+
+IIO currently does not offer suitable channel type for this
+type of measurements hence this patch adds this.
+
+In addition, extra modifiers are introduced used for distinguishing
+between fine pm1, pm2p5 and coarse pm4, pm10 particle measurements, i.e
+IIO_MOD_PM1, IIO_MOD_PM25 and IIO_MOD_PM4, IIO_MOD_PM10.
+
+pmX consists of particles with aerodynamic diameter less or equal to
+X micrometers.
+
+Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
+Acked-by: Matt Ranostay <matt.ranostay@konsulko.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ Documentation/ABI/testing/sysfs-bus-iio | 17 ++++++++++++++++-
+ drivers/iio/industrialio-core.c | 5 +++++
+ include/uapi/linux/iio/types.h | 5 +++++
+ tools/iio/iio_event_monitor.c | 10 ++++++++++
+ 4 files changed, 36 insertions(+), 1 deletion(-)
+
+diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
+index 8127a08e366d..67fd88bf7910 100644
+--- a/Documentation/ABI/testing/sysfs-bus-iio
++++ b/Documentation/ABI/testing/sysfs-bus-iio
+@@ -1684,4 +1684,19 @@ KernelVersion: 4.18
+ Contact: linux-iio@vger.kernel.org
+ Description:
+ Raw (unscaled) phase difference reading from channel Y
+- that can be processed to radians.
+\ No newline at end of file
++ that can be processed to radians.
++
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm1_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm1_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm2p5_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm2p5_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm4_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm4_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm10_input
++What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm10_input
++KernelVersion: 4.22
++Contact: linux-iio@vger.kernel.org
++Description:
++ Mass concentration reading of particulate matter in ug / m3.
++ pmX consists of particles with aerodynamic diameter less or
++ equal to X micrometers.
+diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
+index 4f5cd9f60870..4700fd5d8c90 100644
+--- a/drivers/iio/industrialio-core.c
++++ b/drivers/iio/industrialio-core.c
+@@ -87,6 +87,7 @@ static const char * const iio_chan_type_name_spec[] = {
+ [IIO_GRAVITY] = "gravity",
+ [IIO_POSITIONRELATIVE] = "positionrelative",
+ [IIO_PHASE] = "phase",
++ [IIO_MASSCONCENTRATION] = "massconcentration",
+ };
+
+ static const char * const iio_modifier_names[] = {
+@@ -127,6 +128,10 @@ static const char * const iio_modifier_names[] = {
+ [IIO_MOD_Q] = "q",
+ [IIO_MOD_CO2] = "co2",
+ [IIO_MOD_VOC] = "voc",
++ [IIO_MOD_PM1] = "pm1",
++ [IIO_MOD_PM2P5] = "pm2p5",
++ [IIO_MOD_PM4] = "pm4",
++ [IIO_MOD_PM10] = "pm10",
+ };
+
+ /* relies on pairs of these shared then separate */
+diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
+index 92baabc103ac..c59adac24b1c 100644
+--- a/include/uapi/linux/iio/types.h
++++ b/include/uapi/linux/iio/types.h
+@@ -46,6 +46,7 @@ enum iio_chan_type {
+ IIO_GRAVITY,
+ IIO_POSITIONRELATIVE,
+ IIO_PHASE,
++ IIO_MASSCONCENTRATION,
+ };
+
+ enum iio_modifier {
+@@ -87,6 +88,10 @@ enum iio_modifier {
+ IIO_MOD_VOC,
+ IIO_MOD_LIGHT_UV,
+ IIO_MOD_LIGHT_DUV,
++ IIO_MOD_PM1,
++ IIO_MOD_PM2P5,
++ IIO_MOD_PM4,
++ IIO_MOD_PM10,
+ };
+
+ enum iio_event_type {
+diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
+index ac2de6b7e89f..f6b8003fbe3c 100644
+--- a/tools/iio/iio_event_monitor.c
++++ b/tools/iio/iio_event_monitor.c
+@@ -60,6 +60,7 @@ static const char * const iio_chan_type_name_spec[] = {
+ [IIO_GRAVITY] = "gravity",
+ [IIO_POSITIONRELATIVE] = "positionrelative",
+ [IIO_PHASE] = "phase",
++ [IIO_MASSCONCENTRATION] = "massconcentration",
+ };
+
+ static const char * const iio_ev_type_text[] = {
+@@ -115,6 +116,10 @@ static const char * const iio_modifier_names[] = {
+ [IIO_MOD_Q] = "q",
+ [IIO_MOD_CO2] = "co2",
+ [IIO_MOD_VOC] = "voc",
++ [IIO_MOD_PM1] = "pm1",
++ [IIO_MOD_PM2P5] = "pm2p5",
++ [IIO_MOD_PM4] = "pm4",
++ [IIO_MOD_PM10] = "pm10",
+ };
+
+ static bool event_is_known(struct iio_event_data *event)
+@@ -156,6 +161,7 @@ static bool event_is_known(struct iio_event_data *event)
+ case IIO_GRAVITY:
+ case IIO_POSITIONRELATIVE:
+ case IIO_PHASE:
++ case IIO_MASSCONCENTRATION:
+ break;
+ default:
+ return false;
+@@ -200,6 +206,10 @@ static bool event_is_known(struct iio_event_data *event)
+ case IIO_MOD_Q:
+ case IIO_MOD_CO2:
+ case IIO_MOD_VOC:
++ case IIO_MOD_PM1:
++ case IIO_MOD_PM2P5:
++ case IIO_MOD_PM4:
++ case IIO_MOD_PM10:
+ break;
+ default:
+ return false;
diff --git a/target/linux/generic/backport-4.19/500-v5.1-iio-chemical-add-support-for-Sensirion-SPS30-sensor.patch b/target/linux/generic/backport-4.19/500-v5.1-iio-chemical-add-support-for-Sensirion-SPS30-sensor.patch
new file mode 100644
index 0000000000..73210b8e0e
--- /dev/null
+++ b/target/linux/generic/backport-4.19/500-v5.1-iio-chemical-add-support-for-Sensirion-SPS30-sensor.patch
@@ -0,0 +1,461 @@
+From 232e0f6ddeaee104d64675fe7d0cc142cf955f35 Mon Sep 17 00:00:00 2001
+From: Tomasz Duszynski <tduszyns@gmail.com>
+Date: Fri, 14 Dec 2018 19:28:02 +0100
+Subject: [PATCH] iio: chemical: add support for Sensirion SPS30 sensor
+
+Add support for Sensirion SPS30 particulate matter sensor.
+
+Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ drivers/iio/chemical/Kconfig | 11 +
+ drivers/iio/chemical/Makefile | 1 +
+ drivers/iio/chemical/sps30.c | 407 ++++++++++++++++++++++++++++++++++
+ 3 files changed, 419 insertions(+)
+ create mode 100644 drivers/iio/chemical/sps30.c
+
+diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
+index b8e005be4f87..57832b4360e9 100644
+--- a/drivers/iio/chemical/Kconfig
++++ b/drivers/iio/chemical/Kconfig
+@@ -61,6 +61,17 @@ config IAQCORE
+ iAQ-Core Continuous/Pulsed VOC (Volatile Organic Compounds)
+ sensors
+
++config SPS30
++ tristate "SPS30 particulate matter sensor"
++ depends on I2C
++ select CRC8
++ help
++ Say Y here to build support for the Sensirion SPS30 particulate
++ matter sensor.
++
++ To compile this driver as a module, choose M here: the module will
++ be called sps30.
++
+ config VZ89X
+ tristate "SGX Sensortech MiCS VZ89X VOC sensor"
+ depends on I2C
+diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
+index 2f4c4ba4d781..9f42f4252151 100644
+--- a/drivers/iio/chemical/Makefile
++++ b/drivers/iio/chemical/Makefile
+@@ -9,4 +9,5 @@ obj-$(CONFIG_BME680_I2C) += bme680_i2c.o
+ obj-$(CONFIG_BME680_SPI) += bme680_spi.o
+ obj-$(CONFIG_CCS811) += ccs811.o
+ obj-$(CONFIG_IAQCORE) += ams-iaq-core.o
++obj-$(CONFIG_SPS30) += sps30.o
+ obj-$(CONFIG_VZ89X) += vz89x.o
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+new file mode 100644
+index 000000000000..fa3cd409b90b
+--- /dev/null
++++ b/drivers/iio/chemical/sps30.c
+@@ -0,0 +1,407 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Sensirion SPS30 particulate matter sensor driver
++ *
++ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
++ *
++ * I2C slave address: 0x69
++ *
++ * TODO:
++ * - support for turning on fan cleaning
++ * - support for reading/setting auto cleaning interval
++ */
++
++#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
++
++#include <asm/unaligned.h>
++#include <linux/crc8.h>
++#include <linux/delay.h>
++#include <linux/i2c.h>
++#include <linux/iio/buffer.h>
++#include <linux/iio/iio.h>
++#include <linux/iio/sysfs.h>
++#include <linux/iio/trigger_consumer.h>
++#include <linux/iio/triggered_buffer.h>
++#include <linux/module.h>
++
++#define SPS30_CRC8_POLYNOMIAL 0x31
++/* max number of bytes needed to store PM measurements or serial string */
++#define SPS30_MAX_READ_SIZE 48
++/* sensor measures reliably up to 3000 ug / m3 */
++#define SPS30_MAX_PM 3000
++
++/* SPS30 commands */
++#define SPS30_START_MEAS 0x0010
++#define SPS30_STOP_MEAS 0x0104
++#define SPS30_RESET 0xd304
++#define SPS30_READ_DATA_READY_FLAG 0x0202
++#define SPS30_READ_DATA 0x0300
++#define SPS30_READ_SERIAL 0xd033
++
++enum {
++ PM1,
++ PM2P5,
++ PM4,
++ PM10,
++};
++
++struct sps30_state {
++ struct i2c_client *client;
++ /*
++ * Guards against concurrent access to sensor registers.
++ * Must be held whenever sequence of commands is to be executed.
++ */
++ struct mutex lock;
++};
++
++DECLARE_CRC8_TABLE(sps30_crc8_table);
++
++static int sps30_write_then_read(struct sps30_state *state, u8 *txbuf,
++ int txsize, u8 *rxbuf, int rxsize)
++{
++ int ret;
++
++ /*
++ * Sensor does not support repeated start so instead of
++ * sending two i2c messages in a row we just send one by one.
++ */
++ ret = i2c_master_send(state->client, txbuf, txsize);
++ if (ret != txsize)
++ return ret < 0 ? ret : -EIO;
++
++ if (!rxbuf)
++ return 0;
++
++ ret = i2c_master_recv(state->client, rxbuf, rxsize);
++ if (ret != rxsize)
++ return ret < 0 ? ret : -EIO;
++
++ return 0;
++}
++
++static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
++{
++ /*
++ * Internally sensor stores measurements in a following manner:
++ *
++ * PM1: upper two bytes, crc8, lower two bytes, crc8
++ * PM2P5: upper two bytes, crc8, lower two bytes, crc8
++ * PM4: upper two bytes, crc8, lower two bytes, crc8
++ * PM10: upper two bytes, crc8, lower two bytes, crc8
++ *
++ * What follows next are number concentration measurements and
++ * typical particle size measurement which we omit.
++ */
++ u8 buf[SPS30_MAX_READ_SIZE] = { cmd >> 8, cmd };
++ int i, ret = 0;
++
++ switch (cmd) {
++ case SPS30_START_MEAS:
++ buf[2] = 0x03;
++ buf[3] = 0x00;
++ buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
++ ret = sps30_write_then_read(state, buf, 5, NULL, 0);
++ break;
++ case SPS30_STOP_MEAS:
++ case SPS30_RESET:
++ ret = sps30_write_then_read(state, buf, 2, NULL, 0);
++ break;
++ case SPS30_READ_DATA_READY_FLAG:
++ case SPS30_READ_DATA:
++ case SPS30_READ_SERIAL:
++ /* every two data bytes are checksummed */
++ size += size / 2;
++ ret = sps30_write_then_read(state, buf, 2, buf, size);
++ break;
++ }
++
++ if (ret)
++ return ret;
++
++ /* validate received data and strip off crc bytes */
++ for (i = 0; i < size; i += 3) {
++ u8 crc = crc8(sps30_crc8_table, &buf[i], 2, CRC8_INIT_VALUE);
++
++ if (crc != buf[i + 2]) {
++ dev_err(&state->client->dev,
++ "data integrity check failed\n");
++ return -EIO;
++ }
++
++ *data++ = buf[i];
++ *data++ = buf[i + 1];
++ }
++
++ return 0;
++}
++
++static s32 sps30_float_to_int_clamped(const u8 *fp)
++{
++ int val = get_unaligned_be32(fp);
++ int mantissa = val & GENMASK(22, 0);
++ /* this is fine since passed float is always non-negative */
++ int exp = val >> 23;
++ int fraction, shift;
++
++ /* special case 0 */
++ if (!exp && !mantissa)
++ return 0;
++
++ exp -= 127;
++ if (exp < 0) {
++ /* return values ranging from 1 to 99 */
++ return ((((1 << 23) + mantissa) * 100) >> 23) >> (-exp);
++ }
++
++ /* return values ranging from 100 to 300000 */
++ shift = 23 - exp;
++ val = (1 << exp) + (mantissa >> shift);
++ if (val >= SPS30_MAX_PM)
++ return SPS30_MAX_PM * 100;
++
++ fraction = mantissa & GENMASK(shift - 1, 0);
++
++ return val * 100 + ((fraction * 100) >> shift);
++}
++
++static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)
++{
++ int i, ret, tries = 5;
++ u8 tmp[16];
++
++ while (tries--) {
++ ret = sps30_do_cmd(state, SPS30_READ_DATA_READY_FLAG, tmp, 2);
++ if (ret)
++ return -EIO;
++
++ /* new measurements ready to be read */
++ if (tmp[1] == 1)
++ break;
++
++ msleep_interruptible(300);
++ }
++
++ if (!tries)
++ return -ETIMEDOUT;
++
++ ret = sps30_do_cmd(state, SPS30_READ_DATA, tmp, sizeof(int) * size);
++ if (ret)
++ return ret;
++
++ for (i = 0; i < size; i++)
++ data[i] = sps30_float_to_int_clamped(&tmp[4 * i]);
++
++ return 0;
++}
++
++static irqreturn_t sps30_trigger_handler(int irq, void *p)
++{
++ struct iio_poll_func *pf = p;
++ struct iio_dev *indio_dev = pf->indio_dev;
++ struct sps30_state *state = iio_priv(indio_dev);
++ int ret;
++ s32 data[4 + 2]; /* PM1, PM2P5, PM4, PM10, timestamp */
++
++ mutex_lock(&state->lock);
++ ret = sps30_do_meas(state, data, 4);
++ mutex_unlock(&state->lock);
++ if (ret)
++ goto err;
++
++ iio_push_to_buffers_with_timestamp(indio_dev, data,
++ iio_get_time_ns(indio_dev));
++err:
++ iio_trigger_notify_done(indio_dev->trig);
++
++ return IRQ_HANDLED;
++}
++
++static int sps30_read_raw(struct iio_dev *indio_dev,
++ struct iio_chan_spec const *chan,
++ int *val, int *val2, long mask)
++{
++ struct sps30_state *state = iio_priv(indio_dev);
++ int data[4], ret = -EINVAL;
++
++ switch (mask) {
++ case IIO_CHAN_INFO_PROCESSED:
++ switch (chan->type) {
++ case IIO_MASSCONCENTRATION:
++ mutex_lock(&state->lock);
++ /* read up to the number of bytes actually needed */
++ switch (chan->channel2) {
++ case IIO_MOD_PM1:
++ ret = sps30_do_meas(state, data, 1);
++ break;
++ case IIO_MOD_PM2P5:
++ ret = sps30_do_meas(state, data, 2);
++ break;
++ case IIO_MOD_PM4:
++ ret = sps30_do_meas(state, data, 3);
++ break;
++ case IIO_MOD_PM10:
++ ret = sps30_do_meas(state, data, 4);
++ break;
++ }
++ mutex_unlock(&state->lock);
++ if (ret)
++ return ret;
++
++ *val = data[chan->address] / 100;
++ *val2 = (data[chan->address] % 100) * 10000;
++
++ return IIO_VAL_INT_PLUS_MICRO;
++ default:
++ return -EINVAL;
++ }
++ case IIO_CHAN_INFO_SCALE:
++ switch (chan->type) {
++ case IIO_MASSCONCENTRATION:
++ switch (chan->channel2) {
++ case IIO_MOD_PM1:
++ case IIO_MOD_PM2P5:
++ case IIO_MOD_PM4:
++ case IIO_MOD_PM10:
++ *val = 0;
++ *val2 = 10000;
++
++ return IIO_VAL_INT_PLUS_MICRO;
++ }
++ default:
++ return -EINVAL;
++ }
++ }
++
++ return -EINVAL;
++}
++
++static const struct iio_info sps30_info = {
++ .read_raw = sps30_read_raw,
++};
++
++#define SPS30_CHAN(_index, _mod) { \
++ .type = IIO_MASSCONCENTRATION, \
++ .modified = 1, \
++ .channel2 = IIO_MOD_ ## _mod, \
++ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
++ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
++ .address = _mod, \
++ .scan_index = _index, \
++ .scan_type = { \
++ .sign = 'u', \
++ .realbits = 19, \
++ .storagebits = 32, \
++ .endianness = IIO_CPU, \
++ }, \
++}
++
++static const struct iio_chan_spec sps30_channels[] = {
++ SPS30_CHAN(0, PM1),
++ SPS30_CHAN(1, PM2P5),
++ SPS30_CHAN(2, PM4),
++ SPS30_CHAN(3, PM10),
++ IIO_CHAN_SOFT_TIMESTAMP(4),
++};
++
++static void sps30_stop_meas(void *data)
++{
++ struct sps30_state *state = data;
++
++ sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
++}
++
++static const unsigned long sps30_scan_masks[] = { 0x0f, 0x00 };
++
++static int sps30_probe(struct i2c_client *client)
++{
++ struct iio_dev *indio_dev;
++ struct sps30_state *state;
++ u8 buf[32];
++ int ret;
++
++ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
++ return -EOPNOTSUPP;
++
++ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*state));
++ if (!indio_dev)
++ return -ENOMEM;
++
++ state = iio_priv(indio_dev);
++ i2c_set_clientdata(client, indio_dev);
++ state->client = client;
++ indio_dev->dev.parent = &client->dev;
++ indio_dev->info = &sps30_info;
++ indio_dev->name = client->name;
++ indio_dev->channels = sps30_channels;
++ indio_dev->num_channels = ARRAY_SIZE(sps30_channels);
++ indio_dev->modes = INDIO_DIRECT_MODE;
++ indio_dev->available_scan_masks = sps30_scan_masks;
++
++ mutex_init(&state->lock);
++ crc8_populate_msb(sps30_crc8_table, SPS30_CRC8_POLYNOMIAL);
++
++ ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);
++ if (ret) {
++ dev_err(&client->dev, "failed to reset device\n");
++ return ret;
++ }
++ msleep(300);
++ /*
++ * Power-on-reset causes sensor to produce some glitch on i2c bus and
++ * some controllers end up in error state. Recover simply by placing
++ * some data on the bus, for example STOP_MEAS command, which
++ * is NOP in this case.
++ */
++ sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
++
++ ret = sps30_do_cmd(state, SPS30_READ_SERIAL, buf, sizeof(buf));
++ if (ret) {
++ dev_err(&client->dev, "failed to read serial number\n");
++ return ret;
++ }
++ /* returned serial number is already NUL terminated */
++ dev_info(&client->dev, "serial number: %s\n", buf);
++
++ ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);
++ if (ret) {
++ dev_err(&client->dev, "failed to start measurement\n");
++ return ret;
++ }
++
++ ret = devm_add_action_or_reset(&client->dev, sps30_stop_meas, state);
++ if (ret)
++ return ret;
++
++ ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
++ sps30_trigger_handler, NULL);
++ if (ret)
++ return ret;
++
++ return devm_iio_device_register(&client->dev, indio_dev);
++}
++
++static const struct i2c_device_id sps30_id[] = {
++ { "sps30" },
++ { }
++};
++MODULE_DEVICE_TABLE(i2c, sps30_id);
++
++static const struct of_device_id sps30_of_match[] = {
++ { .compatible = "sensirion,sps30" },
++ { }
++};
++MODULE_DEVICE_TABLE(of, sps30_of_match);
++
++static struct i2c_driver sps30_driver = {
++ .driver = {
++ .name = "sps30",
++ .of_match_table = sps30_of_match,
++ },
++ .id_table = sps30_id,
++ .probe_new = sps30_probe,
++};
++module_i2c_driver(sps30_driver);
++
++MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
++MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor driver");
++MODULE_LICENSE("GPL v2");
diff --git a/target/linux/generic/backport-4.19/501-v5.1-iio-chemical-sps30-add-support-for-self-cleaning.patch b/target/linux/generic/backport-4.19/501-v5.1-iio-chemical-sps30-add-support-for-self-cleaning.patch
new file mode 100644
index 0000000000..9e4b9c2d43
--- /dev/null
+++ b/target/linux/generic/backport-4.19/501-v5.1-iio-chemical-sps30-add-support-for-self-cleaning.patch
@@ -0,0 +1,105 @@
+From c546d49656143855093c7b7fde60866e6e23a69d Mon Sep 17 00:00:00 2001
+From: Tomasz Duszynski <tduszyns@gmail.com>
+Date: Tue, 18 Dec 2018 21:28:09 +0100
+Subject: [PATCH] iio: chemical: sps30: add support for self cleaning
+
+Self cleaning is especially useful in cases where sensor undergoes
+frequent power on/off cycles. In such scenarios it is recommended to
+turn self cleaning at least once per week in order to maintain reliable
+measurements.
+
+Self cleaning is activated by writing 1 to a dedicated attribute.
+Internal fan accelerates to its maximum speed and keeps spinning
+for about 10 seconds blowing out accumulated dust.
+
+Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
+Tested-by: Andreas Brauchli <andreas.brauchli@sensirion.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ Documentation/ABI/testing/sysfs-bus-iio-sps30 | 8 +++++
+ drivers/iio/chemical/sps30.c | 35 ++++++++++++++++++-
+ 2 files changed, 42 insertions(+), 1 deletion(-)
+ create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-sps30
+
+diff --git a/Documentation/ABI/testing/sysfs-bus-iio-sps30 b/Documentation/ABI/testing/sysfs-bus-iio-sps30
+new file mode 100644
+index 000000000000..e7ce2c57635e
+--- /dev/null
++++ b/Documentation/ABI/testing/sysfs-bus-iio-sps30
+@@ -0,0 +1,8 @@
++What: /sys/bus/iio/devices/iio:deviceX/start_cleaning
++Date: December 2018
++KernelVersion: 4.22
++Contact: linux-iio@vger.kernel.org
++Description:
++ Writing 1 starts sensor self cleaning. Internal fan accelerates
++ to its maximum speed and keeps spinning for about 10 seconds in
++ order to blow out accumulated dust.
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index fa3cd409b90b..f3b4390c8f5c 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -7,7 +7,6 @@
+ * I2C slave address: 0x69
+ *
+ * TODO:
+- * - support for turning on fan cleaning
+ * - support for reading/setting auto cleaning interval
+ */
+
+@@ -37,6 +36,7 @@
+ #define SPS30_READ_DATA_READY_FLAG 0x0202
+ #define SPS30_READ_DATA 0x0300
+ #define SPS30_READ_SERIAL 0xd033
++#define SPS30_START_FAN_CLEANING 0x5607
+
+ enum {
+ PM1,
+@@ -104,6 +104,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+ break;
+ case SPS30_STOP_MEAS:
+ case SPS30_RESET:
++ case SPS30_START_FAN_CLEANING:
+ ret = sps30_write_then_read(state, buf, 2, NULL, 0);
+ break;
+ case SPS30_READ_DATA_READY_FLAG:
+@@ -275,7 +276,39 @@ static int sps30_read_raw(struct iio_dev *indio_dev,
+ return -EINVAL;
+ }
+
++static ssize_t start_cleaning_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 sps30_state *state = iio_priv(indio_dev);
++ int val, ret;
++
++ if (kstrtoint(buf, 0, &val) || val != 1)
++ return -EINVAL;
++
++ mutex_lock(&state->lock);
++ ret = sps30_do_cmd(state, SPS30_START_FAN_CLEANING, NULL, 0);
++ mutex_unlock(&state->lock);
++ if (ret)
++ return ret;
++
++ return len;
++}
++
++static IIO_DEVICE_ATTR_WO(start_cleaning, 0);
++
++static struct attribute *sps30_attrs[] = {
++ &iio_dev_attr_start_cleaning.dev_attr.attr,
++ NULL
++};
++
++static const struct attribute_group sps30_attr_group = {
++ .attrs = sps30_attrs,
++};
++
+ static const struct iio_info sps30_info = {
++ .attrs = &sps30_attr_group,
+ .read_raw = sps30_read_raw,
+ };
+
diff --git a/target/linux/generic/backport-4.19/502-v5.1-iio-chemical-sps30-allow-changing-self-cleaning-peri.patch b/target/linux/generic/backport-4.19/502-v5.1-iio-chemical-sps30-allow-changing-self-cleaning-peri.patch
new file mode 100644
index 0000000000..ca3e23b8fc
--- /dev/null
+++ b/target/linux/generic/backport-4.19/502-v5.1-iio-chemical-sps30-allow-changing-self-cleaning-peri.patch
@@ -0,0 +1,297 @@
+From 62129a0849d27cc94ced832bcf9dcde283dcbe08 Mon Sep 17 00:00:00 2001
+From: Tomasz Duszynski <tduszyns@gmail.com>
+Date: Tue, 15 Jan 2019 20:00:06 +0100
+Subject: [PATCH] iio: chemical: sps30: allow changing self cleaning period
+
+Sensor can periodically trigger self cleaning. Period can be changed by
+writing a new value to a dedicated attribute. Upon attribute read
+current period gets returned.
+
+Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ Documentation/ABI/testing/sysfs-bus-iio-sps30 | 20 +++
+ drivers/iio/chemical/sps30.c | 143 +++++++++++++++---
+ 2 files changed, 145 insertions(+), 18 deletions(-)
+
+diff --git a/Documentation/ABI/testing/sysfs-bus-iio-sps30 b/Documentation/ABI/testing/sysfs-bus-iio-sps30
+index e7ce2c57635e..143df8e89d08 100644
+--- a/Documentation/ABI/testing/sysfs-bus-iio-sps30
++++ b/Documentation/ABI/testing/sysfs-bus-iio-sps30
+@@ -6,3 +6,23 @@ Description:
+ Writing 1 starts sensor self cleaning. Internal fan accelerates
+ to its maximum speed and keeps spinning for about 10 seconds in
+ order to blow out accumulated dust.
++
++What: /sys/bus/iio/devices/iio:deviceX/cleaning_period
++Date: January 2019
++KernelVersion: 5.1
++Contact: linux-iio@vger.kernel.org
++Description:
++ Sensor is capable of triggering self cleaning periodically.
++ Period can be changed by writing a new value here. Upon reading
++ the current one is returned. Units are seconds.
++
++ Writing 0 disables periodical self cleaning entirely.
++
++What: /sys/bus/iio/devices/iio:deviceX/cleaning_period_available
++Date: January 2019
++KernelVersion: 5.1
++Contact: linux-iio@vger.kernel.org
++Description:
++ The range of available values in seconds represented as the
++ minimum value, the step and the maximum value, all enclosed in
++ square brackets.
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index f3b4390c8f5c..376fac41ecb5 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -5,9 +5,6 @@
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ * I2C slave address: 0x69
+- *
+- * TODO:
+- * - support for reading/setting auto cleaning interval
+ */
+
+ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+@@ -21,6 +18,7 @@
+ #include <linux/iio/sysfs.h>
+ #include <linux/iio/trigger_consumer.h>
+ #include <linux/iio/triggered_buffer.h>
++#include <linux/kernel.h>
+ #include <linux/module.h>
+
+ #define SPS30_CRC8_POLYNOMIAL 0x31
+@@ -28,6 +26,9 @@
+ #define SPS30_MAX_READ_SIZE 48
+ /* sensor measures reliably up to 3000 ug / m3 */
+ #define SPS30_MAX_PM 3000
++/* minimum and maximum self cleaning periods in seconds */
++#define SPS30_AUTO_CLEANING_PERIOD_MIN 0
++#define SPS30_AUTO_CLEANING_PERIOD_MAX 604800
+
+ /* SPS30 commands */
+ #define SPS30_START_MEAS 0x0010
+@@ -37,6 +38,9 @@
+ #define SPS30_READ_DATA 0x0300
+ #define SPS30_READ_SERIAL 0xd033
+ #define SPS30_START_FAN_CLEANING 0x5607
++#define SPS30_AUTO_CLEANING_PERIOD 0x8004
++/* not a sensor command per se, used only to distinguish write from read */
++#define SPS30_READ_AUTO_CLEANING_PERIOD 0x8005
+
+ enum {
+ PM1,
+@@ -45,6 +49,11 @@ enum {
+ PM10,
+ };
+
++enum {
++ RESET,
++ MEASURING,
++};
++
+ struct sps30_state {
+ struct i2c_client *client;
+ /*
+@@ -52,6 +61,7 @@ struct sps30_state {
+ * Must be held whenever sequence of commands is to be executed.
+ */
+ struct mutex lock;
++ int state;
+ };
+
+ DECLARE_CRC8_TABLE(sps30_crc8_table);
+@@ -107,6 +117,9 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+ case SPS30_START_FAN_CLEANING:
+ ret = sps30_write_then_read(state, buf, 2, NULL, 0);
+ break;
++ case SPS30_READ_AUTO_CLEANING_PERIOD:
++ buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;
++ buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD;
+ case SPS30_READ_DATA_READY_FLAG:
+ case SPS30_READ_DATA:
+ case SPS30_READ_SERIAL:
+@@ -114,6 +127,15 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+ size += size / 2;
+ ret = sps30_write_then_read(state, buf, 2, buf, size);
+ break;
++ case SPS30_AUTO_CLEANING_PERIOD:
++ buf[2] = data[0];
++ buf[3] = data[1];
++ buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
++ buf[5] = data[2];
++ buf[6] = data[3];
++ buf[7] = crc8(sps30_crc8_table, &buf[5], 2, CRC8_INIT_VALUE);
++ ret = sps30_write_then_read(state, buf, 8, NULL, 0);
++ break;
+ }
+
+ if (ret)
+@@ -170,6 +192,14 @@ static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)
+ int i, ret, tries = 5;
+ u8 tmp[16];
+
++ if (state->state == RESET) {
++ ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);
++ if (ret)
++ return ret;
++
++ state->state = MEASURING;
++ }
++
+ while (tries--) {
+ ret = sps30_do_cmd(state, SPS30_READ_DATA_READY_FLAG, tmp, 2);
+ if (ret)
+@@ -276,6 +306,24 @@ static int sps30_read_raw(struct iio_dev *indio_dev,
+ return -EINVAL;
+ }
+
++static int sps30_do_cmd_reset(struct sps30_state *state)
++{
++ int ret;
++
++ ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);
++ msleep(300);
++ /*
++ * Power-on-reset causes sensor to produce some glitch on i2c bus and
++ * some controllers end up in error state. Recover simply by placing
++ * some data on the bus, for example STOP_MEAS command, which
++ * is NOP in this case.
++ */
++ sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
++ state->state = RESET;
++
++ return ret;
++}
++
+ static ssize_t start_cleaning_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+@@ -296,10 +344,82 @@ static ssize_t start_cleaning_store(struct device *dev,
+ return len;
+ }
+
++static ssize_t cleaning_period_show(struct device *dev,
++ struct device_attribute *attr,
++ char *buf)
++{
++ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
++ struct sps30_state *state = iio_priv(indio_dev);
++ u8 tmp[4];
++ int ret;
++
++ mutex_lock(&state->lock);
++ ret = sps30_do_cmd(state, SPS30_READ_AUTO_CLEANING_PERIOD, tmp, 4);
++ mutex_unlock(&state->lock);
++ if (ret)
++ return ret;
++
++ return sprintf(buf, "%d\n", get_unaligned_be32(tmp));
++}
++
++static ssize_t cleaning_period_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 sps30_state *state = iio_priv(indio_dev);
++ int val, ret;
++ u8 tmp[4];
++
++ if (kstrtoint(buf, 0, &val))
++ return -EINVAL;
++
++ if ((val < SPS30_AUTO_CLEANING_PERIOD_MIN) ||
++ (val > SPS30_AUTO_CLEANING_PERIOD_MAX))
++ return -EINVAL;
++
++ put_unaligned_be32(val, tmp);
++
++ mutex_lock(&state->lock);
++ ret = sps30_do_cmd(state, SPS30_AUTO_CLEANING_PERIOD, tmp, 0);
++ if (ret) {
++ mutex_unlock(&state->lock);
++ return ret;
++ }
++
++ msleep(20);
++
++ /*
++ * sensor requires reset in order to return up to date self cleaning
++ * period
++ */
++ ret = sps30_do_cmd_reset(state);
++ if (ret)
++ dev_warn(dev,
++ "period changed but reads will return the old value\n");
++
++ mutex_unlock(&state->lock);
++
++ return len;
++}
++
++static ssize_t cleaning_period_available_show(struct device *dev,
++ struct device_attribute *attr,
++ char *buf)
++{
++ return snprintf(buf, PAGE_SIZE, "[%d %d %d]\n",
++ SPS30_AUTO_CLEANING_PERIOD_MIN, 1,
++ SPS30_AUTO_CLEANING_PERIOD_MAX);
++}
++
+ static IIO_DEVICE_ATTR_WO(start_cleaning, 0);
++static IIO_DEVICE_ATTR_RW(cleaning_period, 0);
++static IIO_DEVICE_ATTR_RO(cleaning_period_available, 0);
+
+ static struct attribute *sps30_attrs[] = {
+ &iio_dev_attr_start_cleaning.dev_attr.attr,
++ &iio_dev_attr_cleaning_period.dev_attr.attr,
++ &iio_dev_attr_cleaning_period_available.dev_attr.attr,
+ NULL
+ };
+
+@@ -362,6 +482,7 @@ static int sps30_probe(struct i2c_client *client)
+ state = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
+ state->client = client;
++ state->state = RESET;
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &sps30_info;
+ indio_dev->name = client->name;
+@@ -373,19 +494,11 @@ static int sps30_probe(struct i2c_client *client)
+ mutex_init(&state->lock);
+ crc8_populate_msb(sps30_crc8_table, SPS30_CRC8_POLYNOMIAL);
+
+- ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);
++ ret = sps30_do_cmd_reset(state);
+ if (ret) {
+ dev_err(&client->dev, "failed to reset device\n");
+ return ret;
+ }
+- msleep(300);
+- /*
+- * Power-on-reset causes sensor to produce some glitch on i2c bus and
+- * some controllers end up in error state. Recover simply by placing
+- * some data on the bus, for example STOP_MEAS command, which
+- * is NOP in this case.
+- */
+- sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
+
+ ret = sps30_do_cmd(state, SPS30_READ_SERIAL, buf, sizeof(buf));
+ if (ret) {
+@@ -395,12 +508,6 @@ static int sps30_probe(struct i2c_client *client)
+ /* returned serial number is already NUL terminated */
+ dev_info(&client->dev, "serial number: %s\n", buf);
+
+- ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);
+- if (ret) {
+- dev_err(&client->dev, "failed to start measurement\n");
+- return ret;
+- }
+-
+ ret = devm_add_action_or_reset(&client->dev, sps30_stop_meas, state);
+ if (ret)
+ return ret;
diff --git a/target/linux/generic/backport-4.19/503-v5.1-iio-chemical-sps30-remove-printk-format-specifier.patch b/target/linux/generic/backport-4.19/503-v5.1-iio-chemical-sps30-remove-printk-format-specifier.patch
new file mode 100644
index 0000000000..8cdd0a718d
--- /dev/null
+++ b/target/linux/generic/backport-4.19/503-v5.1-iio-chemical-sps30-remove-printk-format-specifier.patch
@@ -0,0 +1,27 @@
+From 3fa30bf7004bb8069826ef85487f4753666a73da Mon Sep 17 00:00:00 2001
+From: Tomasz Duszynski <tduszyns@gmail.com>
+Date: Sat, 2 Feb 2019 10:00:03 +0100
+Subject: [PATCH] iio: chemical: sps30: remove printk format specifier
+
+pr_fmt is used by printk wrappers. There are not any in the driver
+code so remove the format specifier.
+
+Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ drivers/iio/chemical/sps30.c | 2 --
+ 1 file changed, 2 deletions(-)
+
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index 376fac41ecb5..e03a28a67146 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -7,8 +7,6 @@
+ * I2C slave address: 0x69
+ */
+
+-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+-
+ #include <asm/unaligned.h>
+ #include <linux/crc8.h>
+ #include <linux/delay.h>
diff --git a/target/linux/generic/backport-4.19/504-v5.1-iio-chemical-sps30-fix-a-loop-timeout-test.patch b/target/linux/generic/backport-4.19/504-v5.1-iio-chemical-sps30-fix-a-loop-timeout-test.patch
new file mode 100644
index 0000000000..e0fcdc2ce2
--- /dev/null
+++ b/target/linux/generic/backport-4.19/504-v5.1-iio-chemical-sps30-fix-a-loop-timeout-test.patch
@@ -0,0 +1,28 @@
+From 905889b4a34c753a538015f0b2cdaa0c9e3a4fd5 Mon Sep 17 00:00:00 2001
+From: Dan Carpenter <dan.carpenter@oracle.com>
+Date: Sat, 9 Feb 2019 12:03:52 +0300
+Subject: [PATCH] iio: chemical: sps30: fix a loop timeout test
+
+The "while (tries--) {" loop is a postop so it exits with "tries" set
+to -1.
+
+Fixes: 232e0f6ddeae ("iio: chemical: add support for Sensirion SPS30 sensor")
+Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+---
+ drivers/iio/chemical/sps30.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index e03a28a67146..375df5060ed5 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -210,7 +210,7 @@ static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)
+ msleep_interruptible(300);
+ }
+
+- if (!tries)
++ if (tries == -1)
+ return -ETIMEDOUT;
+
+ ret = sps30_do_cmd(state, SPS30_READ_DATA, tmp, sizeof(int) * size);
diff --git a/target/linux/generic/backport-4.19/505-v5.1-iio-chemical-sps30-Supress-some-switch-fallthrough-w.patch b/target/linux/generic/backport-4.19/505-v5.1-iio-chemical-sps30-Supress-some-switch-fallthrough-w.patch
new file mode 100644
index 0000000000..a1c0b3ddca
--- /dev/null
+++ b/target/linux/generic/backport-4.19/505-v5.1-iio-chemical-sps30-Supress-some-switch-fallthrough-w.patch
@@ -0,0 +1,36 @@
+From 59b9bb0abca9efe47207301dbaf0d1beee2bd0f7 Mon Sep 17 00:00:00 2001
+From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+Date: Sat, 9 Feb 2019 19:32:58 +0000
+Subject: [PATCH] iio:chemical:sps30 Supress some switch fallthrough warnings.
+
+Fixes warnings reported on linux-next but marking one path
+and adding an explicit return in the other.
+
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+Cc: Andreas Brauchli <a.brauchli@elementarea.net>
+Acked-by: Tomasz Duszynski <tduszyns@gmail.com>
+---
+ drivers/iio/chemical/sps30.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index 375df5060ed5..edbb956e81e8 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -118,6 +118,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+ case SPS30_READ_AUTO_CLEANING_PERIOD:
+ buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;
+ buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD;
++ /* fall through */
+ case SPS30_READ_DATA_READY_FLAG:
+ case SPS30_READ_DATA:
+ case SPS30_READ_SERIAL:
+@@ -295,6 +296,8 @@ static int sps30_read_raw(struct iio_dev *indio_dev,
+ *val2 = 10000;
+
+ return IIO_VAL_INT_PLUS_MICRO;
++ default:
++ return -EINVAL;
+ }
+ default:
+ return -EINVAL;
diff --git a/target/linux/generic/backport-4.19/506-v5.1-iio-chemical-sps30-Explicity-truncate-constant-by-ma.patch b/target/linux/generic/backport-4.19/506-v5.1-iio-chemical-sps30-Explicity-truncate-constant-by-ma.patch
new file mode 100644
index 0000000000..6b31483070
--- /dev/null
+++ b/target/linux/generic/backport-4.19/506-v5.1-iio-chemical-sps30-Explicity-truncate-constant-by-ma.patch
@@ -0,0 +1,33 @@
+From 78b75ab3f8c9dfac563b81105a1b838ec37a940e Mon Sep 17 00:00:00 2001
+From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+Date: Sun, 13 Oct 2019 10:55:15 +0100
+Subject: [PATCH] iio: chemical: sps30: Explicity truncate constant by masking
+
+When breaking up a constant to write to two 8 bit registers
+it isn't obvious to sparse that it was intentional.
+
+CHECK drivers/iio/chemical/sps30.c
+drivers/iio/chemical/sps30.c:120:30: warning: cast truncates bits from constant value (8004 becomes 4)
+
+So in the interests of minimising noisy warnings, let us add
+a mask.
+
+Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+Acked-by: Tomasz Duszynski <tduszyns@gmail.com>
+---
+ drivers/iio/chemical/sps30.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
+index edbb956e81e8..acb9f8ecbb3d 100644
+--- a/drivers/iio/chemical/sps30.c
++++ b/drivers/iio/chemical/sps30.c
+@@ -117,7 +117,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
+ break;
+ case SPS30_READ_AUTO_CLEANING_PERIOD:
+ buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;
+- buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD;
++ buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff);
+ /* fall through */
+ case SPS30_READ_DATA_READY_FLAG:
+ case SPS30_READ_DATA:
diff --git a/target/linux/generic/backport-4.19/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch b/target/linux/generic/backport-4.19/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch
new file mode 100644
index 0000000000..a2b274f75e
--- /dev/null
+++ b/target/linux/generic/backport-4.19/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch
@@ -0,0 +1,32 @@
+From 61338e27e2eef3bfcd3df5c39cec5b9dc10ba25c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20=C5=A0tetiar?= <ynezz@true.cz>
+Date: Sun, 23 Feb 2020 22:08:25 +0100
+Subject: [PATCH] iio: chemical: sps30: fix missing triggered buffer dependency
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+SPS30 uses triggered buffer, but the dependency is not specified in the
+Kconfig file. Fix this by selecting IIO_BUFFER and IIO_TRIGGERED_BUFFER
+config symbols.
+
+Cc: stable@vger.kernel.org
+Fixes: 232e0f6ddeae ("iio: chemical: add support for Sensirion SPS30 sensor")
+Signed-off-by: Petr Štetiar <ynezz@true.cz>
+---
+ drivers/iio/chemical/Kconfig | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
+index 0b91de4df8f4..a7e65a59bf42 100644
+--- a/drivers/iio/chemical/Kconfig
++++ b/drivers/iio/chemical/Kconfig
+@@ -91,6 +91,8 @@ config SPS30
+ tristate "SPS30 particulate matter sensor"
+ depends on I2C
+ select CRC8
++ select IIO_BUFFER
++ select IIO_TRIGGERED_BUFFER
+ help
+ Say Y here to build support for the Sensirion SPS30 particulate
+ matter sensor.
diff --git a/target/linux/generic/backport-5.4/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch b/target/linux/generic/backport-5.4/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch
new file mode 100644
index 0000000000..a2b274f75e
--- /dev/null
+++ b/target/linux/generic/backport-5.4/507-v5.6-iio-chemical-sps30-fix-missing-triggered-buffer-depe.patch
@@ -0,0 +1,32 @@
+From 61338e27e2eef3bfcd3df5c39cec5b9dc10ba25c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20=C5=A0tetiar?= <ynezz@true.cz>
+Date: Sun, 23 Feb 2020 22:08:25 +0100
+Subject: [PATCH] iio: chemical: sps30: fix missing triggered buffer dependency
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+SPS30 uses triggered buffer, but the dependency is not specified in the
+Kconfig file. Fix this by selecting IIO_BUFFER and IIO_TRIGGERED_BUFFER
+config symbols.
+
+Cc: stable@vger.kernel.org
+Fixes: 232e0f6ddeae ("iio: chemical: add support for Sensirion SPS30 sensor")
+Signed-off-by: Petr Štetiar <ynezz@true.cz>
+---
+ drivers/iio/chemical/Kconfig | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
+index 0b91de4df8f4..a7e65a59bf42 100644
+--- a/drivers/iio/chemical/Kconfig
++++ b/drivers/iio/chemical/Kconfig
+@@ -91,6 +91,8 @@ config SPS30
+ tristate "SPS30 particulate matter sensor"
+ depends on I2C
+ select CRC8
++ select IIO_BUFFER
++ select IIO_TRIGGERED_BUFFER
+ help
+ Say Y here to build support for the Sensirion SPS30 particulate
+ matter sensor.