From c546d49656143855093c7b7fde60866e6e23a69d Mon Sep 17 00:00:00 2001 From: Tomasz Duszynski 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 Tested-by: Andreas Brauchli Signed-off-by: Jonathan Cameron --- 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 --- /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. --- 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_sta 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 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, };