| Message ID | 20190113100912.29665-1-tduszyns@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3] iio: chemical: sps30: allow changing self cleaning period | expand |
On Sun, Jan 13, 2019 at 11:09:12AM +0100, Tomasz Duszynski wrote: > 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> > --- > v3: > * add info about used units to attribute docs > > v2: > * return available values formated as a range > * tweak naming a little (interval -> period) > > 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..fe5f6309191b 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; Should this be || instead of &&? Jeremy > + > + 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; > -- > 2.20.1 >
On Mon, Jan 14, 2019 at 05:15:39PM -0700, Jeremy Fertic wrote: > On Sun, Jan 13, 2019 at 11:09:12AM +0100, Tomasz Duszynski wrote: > > 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> > > --- > > v3: > > * add info about used units to attribute docs > > > > v2: > > * return available values formated as a range > > * tweak naming a little (interval -> period) > > > > 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..fe5f6309191b 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; > > Should this be || instead of &&? > Definitely. Thanks for catching this. > Jeremy > > > + > > + 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; > > -- > > 2.20.1 > >
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..fe5f6309191b 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;
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> --- v3: * add info about used units to attribute docs v2: * return available values formated as a range * tweak naming a little (interval -> period) Documentation/ABI/testing/sysfs-bus-iio-sps30 | 20 +++ drivers/iio/chemical/sps30.c | 143 +++++++++++++++--- 2 files changed, 145 insertions(+), 18 deletions(-) -- 2.20.1