nuttx/drivers/sensors/sps30.c

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/****************************************************************************
* drivers/sensors/sps30.c
* Driver for the Sensirion SPS30 particulate matter sensor
*
* Copyright (C) 2019 Haltian Ltd. All rights reserved.
* Author: Jussi Kivilinna <jussi.kivilinna@haltian.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <time.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/signal.h>
#include <nuttx/fs/fs.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/sensors/sps30.h>
#include <nuttx/random.h>
#if defined(CONFIG_SENSORS_SPS30)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_SPS30_DEBUG
# define sps30_dbg(x, ...) _info(x, ##__VA_ARGS__)
#else
# define sps30_dbg(x, ...) sninfo(x, ##__VA_ARGS__)
#endif
#ifndef CONFIG_SPS30_I2C_FREQUENCY
# define CONFIG_SPS30_I2C_FREQUENCY 100000
#endif
#define SPS30_MEASUREMENT_INTERVAL 1 /* one second, fixed in hw */
#define SPS30_MEASUREMENT_MODE 0x0300
#define SPS30_I2C_RETRIES 3
/* SPS30 command words */
#define SPS30_CMD_START_MEASUREMENT 0x0010
#define SPS30_CMD_STOP_MEASUREMENT 0x0104
#define SPS30_CMD_GET_DATA_READY 0x0202
#define SPS30_CMD_READ_MEASUREMENT 0x0300
#define SPS30_CMD_SET_AUTO_CLEANING_INTERVAL 0x8004
#define SPS30_CMD_START_FAN_CLEANING 0x5607
#define SPS30_CMD_READ_ARTICLE_CODE 0xd025
#define SPS30_CMD_READ_SERIAL_NUMBER 0xd033
#define SPS30_CMD_SOFT_RESET 0xd304
/****************************************************************************
* Private
****************************************************************************/
struct sps30_dev_s
{
#ifdef CONFIG_SPS30_I2C
FAR struct i2c_master_s *i2c; /* I2C interface */
uint8_t addr; /* I2C address */
#endif
bool valid; /* If cached readings are valid */
bool started; /* If continuous measurement is enabled */
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
bool unlinked; /* True, driver has been unlinked */
#endif
struct timespec last_update; /* Last time when sensor was read */
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
int16_t crefs; /* Number of open references */
#endif
sem_t devsem;
/* Cached sensor values */
struct sps30_conv_data_s data;
};
struct sps30_word_s
{
uint8_t data[2];
uint8_t crc;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* IO Helpers */
#ifdef CONFIG_SPS30_I2C
static int sps30_do_transfer(FAR struct i2c_master_s *i2c,
FAR struct i2c_msg_s *msgv,
size_t nmsg);
#endif
static int sps30_write_cmd(FAR struct sps30_dev_s *priv, uint16_t cmd,
FAR struct sps30_word_s *params,
unsigned int num_params);
static int sps30_read_cmd(FAR struct sps30_dev_s *priv, uint16_t cmd,
FAR struct sps30_word_s *words,
unsigned int num_words);
/* Data conversion */
static uint8_t sps30_crc_word(uint16_t word);
static void sps30_set_command_param(FAR struct sps30_word_s *param,
uint16_t value);
static int sps30_check_data_crc(FAR const struct sps30_word_s *words,
unsigned int num_words);
static uint16_t sps30_data_word_to_uint16(FAR const struct sps30_word_s *word);
static float sps30_data_words_to_float(FAR const struct sps30_word_s words[2]);
/* Driver features */
static int sps30_read_values(FAR struct sps30_dev_s *priv,
FAR struct sps30_conv_data_s *out, bool wait);
static int sps30_configure(FAR struct sps30_dev_s *priv, bool start);
static int sps30_read_dev_info(FAR struct sps30_dev_s *priv, uint16_t cmd,
char *out, size_t outlen);
/* Character driver methods */
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
static int sps30_open(FAR struct file *filep);
static int sps30_close(FAR struct file *filep);
#endif
static ssize_t sps30_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t sps30_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
static int sps30_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
static int sps30_unlink(FAR struct inode *inode);
#endif
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_sps30fops =
{
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
sps30_open, /* open */
sps30_close, /* close */
#else
NULL, /* open */
NULL, /* close */
#endif
sps30_read, /* read */
sps30_write, /* write */
NULL, /* seek */
sps30_ioctl, /* ioctl */
NULL /* poll */
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
, sps30_unlink /* unlink */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sps30_do_transfer
****************************************************************************/
#ifdef CONFIG_SPS30_I2C
static int sps30_do_transfer(FAR struct i2c_master_s *i2c,
FAR struct i2c_msg_s *msgv,
size_t nmsg)
{
int ret = -EIO;
int retries;
for (retries = 0; retries < SPS30_I2C_RETRIES; retries++)
{
ret = I2C_TRANSFER(i2c, msgv, nmsg);
if (ret >= 0)
{
return 0;
}
else
{
/* Some error. Try to reset I2C bus and keep trying. */
#ifdef CONFIG_I2C_RESET
if (retries == SPS30_I2C_RETRIES - 1)
{
break;
}
ret = I2C_RESET(i2c);
if (ret < 0)
{
sps30_dbg("I2C_RESET failed: %d\n", ret);
return ret;
}
#endif
}
}
sps30_dbg("xfer failed: %d\n", ret);
return ret;
}
#endif
/****************************************************************************
* Name: sps30_write_cmd
****************************************************************************/
static int sps30_write_cmd(FAR struct sps30_dev_s *priv, uint16_t cmd,
FAR struct sps30_word_s *params,
unsigned int num_params)
{
#ifdef CONFIG_SPS30_I2C
struct i2c_msg_s msg[2];
uint8_t cmd_buf[2];
int ret;
cmd_buf[0] = cmd >> 8;
cmd_buf[1] = cmd >> 0;
msg[0].frequency = CONFIG_SPS30_I2C_FREQUENCY;
msg[0].addr = priv->addr;
msg[0].flags = 0;
msg[0].buffer = cmd_buf;
msg[0].length = 2;
if (num_params)
{
msg[1].frequency = CONFIG_SPS30_I2C_FREQUENCY;
msg[1].addr = priv->addr;
msg[1].flags = I2C_M_NOSTART;
msg[1].buffer = (FAR uint8_t *)params;
msg[1].length = num_params * sizeof(*params);
}
ret = sps30_do_transfer(priv->i2c, msg, (num_params) ? 2 : 1);
sps30_dbg("cmd: 0x%04X num_params: %d ret: %d\n",
cmd, num_params, ret);
return (ret >= 0) ? OK : ret;
#else
/* UART mode not implemented yet. */
return -ENODEV;
#endif
}
/****************************************************************************
* Name: sps30_read_words
****************************************************************************/
static int sps30_read_cmd(FAR struct sps30_dev_s *priv, uint16_t cmd,
FAR struct sps30_word_s *words,
unsigned int num_words)
{
#ifdef CONFIG_SPS30_I2C
struct i2c_msg_s msg[1];
uint8_t addr_buf[2];
int ret;
addr_buf[0] = cmd >> 8;
addr_buf[1] = cmd >> 0;
msg[0].frequency = CONFIG_SPS30_I2C_FREQUENCY;
msg[0].addr = priv->addr;
msg[0].flags = 0;
msg[0].buffer = addr_buf;
msg[0].length = 2;
ret = sps30_do_transfer(priv->i2c, msg, 1);
sps30_dbg("cmd: 0x%04X ret: %d\n", cmd, ret);
if (ret < 0)
{
return ret;
}
msg[0].frequency = CONFIG_SPS30_I2C_FREQUENCY;
msg[0].addr = priv->addr;
msg[0].flags = I2C_M_READ;
msg[0].buffer = (FAR uint8_t *)words;
msg[0].length = num_words * sizeof(*words);
ret = sps30_do_transfer(priv->i2c, msg, 1);
sps30_dbg("read cmd: 0x%04X num_params: %d ret: %d\n",
cmd, num_words, ret);
return (ret >= 0) ? OK : ret;
#else
/* UART mode not implemented yet. */
return -ENODEV;
#endif
}
/****************************************************************************
* Name: sps30_crc_word
****************************************************************************/
static uint8_t sps30_crc_word(uint16_t word)
{
static const uint8_t crc_table[16] =
{
0x00, 0x31, 0x62, 0x53, 0xc4, 0xf5, 0xa6, 0x97,
0xb9, 0x88, 0xdb, 0xea, 0x7d, 0x4c, 0x1f, 0x2e
};
uint8_t crc = 0xff;
crc ^= word >> 8;
crc = (crc << 4) ^ crc_table[crc >> 4];
crc = (crc << 4) ^ crc_table[crc >> 4];
crc ^= word >> 0;
crc = (crc << 4) ^ crc_table[crc >> 4];
crc = (crc << 4) ^ crc_table[crc >> 4];
return crc;
}
/****************************************************************************
* Name: sps30_set_command_param
****************************************************************************/
static void sps30_set_command_param(FAR struct sps30_word_s *param,
uint16_t value)
{
param->data[0] = value >> 8;
param->data[1] = value >> 0;
param->crc = sps30_crc_word(value);
}
/****************************************************************************
* Name: sps30_data_words_to_float
****************************************************************************/
static float sps30_data_words_to_float(FAR const struct sps30_word_s words[2])
{
uint8_t data[4];
float value;
data[3] = words[0].data[0];
data[2] = words[0].data[1];
data[1] = words[1].data[0];
data[0] = words[1].data[1];
memcpy(&value, data, 4);
return value;
}
/****************************************************************************
* Name: sps30_data_word_to_uint16
****************************************************************************/
static uint16_t sps30_data_word_to_uint16(FAR const struct sps30_word_s *word)
{
return (word[0].data[0] << 8) | (word[0].data[1]);
}
/****************************************************************************
* Name: sps30_crc_word
****************************************************************************/
static int sps30_check_data_crc(FAR const struct sps30_word_s *words,
unsigned int num_words)
{
while (num_words)
{
if (sps30_crc_word(sps30_data_word_to_uint16(words)) != words->crc)
{
return -1;
}
num_words--;
words++;
}
return 0;
}
/****************************************************************************
* Name: sps30_softreset
*
* Description:
* Reset the SPS30 sensor. This takes less than 2000 ms.
*
****************************************************************************/
static int sps30_softreset(FAR struct sps30_dev_s *priv)
{
int ret;
ret = sps30_write_cmd(priv, SPS30_CMD_SOFT_RESET, NULL, 0);
if (ret < 0)
{
return ret;
}
return 0;
}
/****************************************************************************
* Name: has_time_passed
*
* Description:
* Return true if curr >= start + secs_since_start
*
****************************************************************************/
static bool has_time_passed(struct timespec curr,
struct timespec start,
unsigned int secs_since_start)
{
if ((long)((start.tv_sec + secs_since_start) - curr.tv_sec) == 0)
{
return start.tv_nsec <= curr.tv_nsec;
}
return (long)((start.tv_sec + secs_since_start) - curr.tv_sec) <= 0;
}
/****************************************************************************
* Name: sps30_read_values
****************************************************************************/
static int sps30_read_values(FAR struct sps30_dev_s *priv,
FAR struct sps30_conv_data_s *out, bool wait)
{
struct sps30_word_s data[20];
struct timespec ts;
int ret;
clock_gettime(CLOCK_REALTIME, &ts);
if (wait || !priv->valid ||
has_time_passed(ts, priv->last_update, SPS30_MEASUREMENT_INTERVAL))
{
while (1)
{
/* Wait data to be ready. */
ret = sps30_read_cmd(priv, SPS30_CMD_GET_DATA_READY, data, 1);
if (ret < 0)
{
sps30_dbg("ERROR: sps30_read_cmd failed: %d\n", ret);
return ret;
}
if (sps30_check_data_crc(data, 1) < 0)
{
sps30_dbg("ERROR: sps30_read_words crc failed\n");
ret = -EIO;
return ret;
}
if (sps30_data_word_to_uint16(data) != 0x0001)
{
if (!wait)
{
sps30_dbg("ERROR: data not ready\n");
ret = -EAGAIN;
return ret;
}
ret = nxsig_usleep(500 * 1000);
if (ret == -EINTR)
{
return ret;
}
}
else
{
break;
}
}
/* Read the raw data */
ret = sps30_read_cmd(priv, SPS30_CMD_READ_MEASUREMENT, data, 20);
if (ret < 0)
{
sps30_dbg("ERROR: sps30_read_cmd failed: %d\n", ret);
return ret;
}
if (sps30_check_data_crc(data, 20) < 0)
{
sps30_dbg("ERROR: sps30_read_words crc failed\n");
ret = -EIO;
return ret;
}
add_sensor_randomness(((data[0].crc ^ data[1].crc) << 0) ^
((data[2].crc ^ data[3].crc) << 8) ^
((data[4].crc ^ data[5].crc) << 16) ^
((data[6].crc ^ data[7].crc) << 24) ^
((data[8].crc ^ data[9].crc) << 0) ^
((data[10].crc ^ data[11].crc) << 8) ^
((data[12].crc ^ data[13].crc) << 16) ^
((data[14].crc ^ data[15].crc) << 24) ^
((data[16].crc ^ data[17].crc) << 0) ^
((data[18].crc ^ data[19].crc) << 8));
priv->data.mass_concenration_pm1_0 =
sps30_data_words_to_float(data + 0);
priv->data.mass_concenration_pm2_5 =
sps30_data_words_to_float(data + 2);
priv->data.mass_concenration_pm4_0 =
sps30_data_words_to_float(data + 4);
priv->data.mass_concenration_pm10 =
sps30_data_words_to_float(data + 6);
priv->data.number_concenration_pm0_5 =
sps30_data_words_to_float(data + 8);
priv->data.number_concenration_pm1_0 =
sps30_data_words_to_float(data + 10);
priv->data.number_concenration_pm2_5 =
sps30_data_words_to_float(data + 12);
priv->data.number_concenration_pm4_0 =
sps30_data_words_to_float(data + 14);
priv->data.number_concenration_pm10 =
sps30_data_words_to_float(data + 16);
priv->data.typical_particle_size =
sps30_data_words_to_float(data + 18);
priv->last_update = ts;
priv->valid = true;
/* Wait data to be ready. */
ret = sps30_read_cmd(priv, SPS30_CMD_GET_DATA_READY, data, 1);
if (ret < 0)
{
sps30_dbg("ERROR: sps30_read_cmd failed: %d\n", ret);
}
}
*out = priv->data;
return OK;
}
/****************************************************************************
* Name: sps30_read_dev_info
****************************************************************************/
static int sps30_read_dev_info(FAR struct sps30_dev_s *priv, uint16_t cmd,
char *out, size_t outlen)
{
struct sps30_word_s buf[16];
int ret;
ret = sps30_read_cmd(priv, cmd, buf, 16);
if (ret < 0)
{
sps30_dbg("ERROR: sps30_read_cmd failed: %d\n", ret);
return ret;
}
if (sps30_check_data_crc(buf, 16) < 0)
{
sps30_dbg("ERROR: sps30_read_words crc failed\n");
ret = -EIO;
return ret;
}
ret = 0;
while (outlen && ret < 32)
{
*out = buf[ret / 2].data[ret % 2];
ret++;
out++;
outlen--;
}
if (outlen)
{
*out = '\0';
}
return ret;
}
/****************************************************************************
* Name: sps30_configure
****************************************************************************/
static int sps30_configure(FAR struct sps30_dev_s *priv, bool start)
{
struct sps30_word_s param;
int ret;
if (!start)
{
/* Stop measurements. */
ret = sps30_write_cmd(priv, SPS30_CMD_STOP_MEASUREMENT, &param, 1);
if (ret >= 0)
{
priv->started = false;
}
}
else
{
/* Start measurements (and set pressure compensation). */
sps30_set_command_param(&param, SPS30_MEASUREMENT_MODE);
ret = sps30_write_cmd(priv, SPS30_CMD_START_MEASUREMENT, &param, 1);
if (ret >= 0)
{
priv->started = true;
}
}
return ret;
}
/****************************************************************************
* Name: sps30_open
*
* Description:
* This function is called whenever the SPS30x device is opened.
*
****************************************************************************/
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
static int sps30_open(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct sps30_dev_s *priv = inode->i_private;
union
{
uint32_t u32[8];
char c[32];
} code, sn;
int ret;
/* Get exclusive access */
do
{
ret = nxsem_wait(&priv->devsem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
/* Increment the count of open references on the driver */
priv->crefs++;
DEBUGASSERT(priv->crefs > 0);
if (priv->crefs == 1)
{
/* Read device information. */
ret = sps30_read_dev_info(priv, SPS30_CMD_READ_ARTICLE_CODE, code.c,
sizeof(code.c));
if (ret >= 0)
{
ret = sps30_read_dev_info(priv, SPS30_CMD_READ_SERIAL_NUMBER, sn.c,
sizeof(sn.c));
if (ret >= 0)
{
static int once;
if (!once)
{
once = 1;
up_rngaddentropy(RND_SRC_SENSOR, code.u32,
(strlen(code.c) + 3) / 4);
up_rngaddentropy(RND_SRC_SENSOR, sn.u32,
(strlen(sn.c) + 3) / 4);
}
sps30_dbg("article code: \"%.*s\"\n", 32, code.c);
sps30_dbg("serial number: \"%.*s\"\n", 32, sn.c);
/* Start sensor. */
ret = sps30_configure(priv, true);
}
}
}
if (ret < 0)
{
priv->crefs--;
}
nxsem_post(&priv->devsem);
return ret;
}
#endif
/****************************************************************************
* Name: sps30_close
*
* Description:
* This routine is called when the SPS30 device is closed.
*
****************************************************************************/
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
static int sps30_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct sps30_dev_s *priv = inode->i_private;
int ret;
/* Get exclusive access */
do
{
ret = nxsem_wait(&priv->devsem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
/* Decrement the count of open references on the driver */
DEBUGASSERT(priv->crefs > 0);
priv->crefs--;
/* If the count has decremented to zero and the driver has been unlinked,
* then free memory now.
*/
if (priv->crefs <= 0 && priv->unlinked)
{
nxsem_destroy(&priv->devsem);
kmm_free(priv);
return OK;
}
nxsem_post(&priv->devsem);
return OK;
}
#endif
/****************************************************************************
* Name: sps30_read
****************************************************************************/
static ssize_t sps30_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR struct sps30_dev_s *priv = inode->i_private;
ssize_t length = 0;
struct sps30_conv_data_s data;
unsigned int data100[10];
int ret;
/* Get exclusive access */
do
{
ret = nxsem_wait(&priv->devsem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
if (priv->unlinked)
{
/* Do not allow operations on unlinked sensors. This allows
* sensor use on hot swappable I2C bus.
*/
nxsem_post(&priv->devsem);
return -ENODEV;
}
#endif
if (!priv->started)
{
return -ENODATA;
}
ret = sps30_read_values(priv, &data, !(filep->f_oflags & O_NONBLOCK));
if (ret < 0)
{
sps30_dbg("cannot read data: %d\n", ret);
}
else
{
/* This interface is mainly intended for easy debugging in nsh. */
data100[0] = abs(data.mass_concenration_pm1_0 * 100);
data100[1] = abs(data.mass_concenration_pm2_5 * 100);
data100[2] = abs(data.mass_concenration_pm4_0 * 100);
data100[3] = abs(data.mass_concenration_pm10 * 100);
data100[4] = abs(data.number_concenration_pm0_5 * 100);
data100[5] = abs(data.number_concenration_pm1_0 * 100);
data100[6] = abs(data.number_concenration_pm2_5 * 100);
data100[7] = abs(data.number_concenration_pm4_0 * 100);
data100[8] = abs(data.number_concenration_pm10 * 100);
data100[9] = abs(data.typical_particle_size * 100);
length = snprintf(buffer, buflen,
"%u.%02u %u.%02u %u.%02u %u.%02u %u.%02u "
"%u.%02u %u.%02u %u.%02u %u.%02u %u.%02u\n",
data100[0] / 100, data100[0] % 100,
data100[1] / 100, data100[1] % 100,
data100[2] / 100, data100[2] % 100,
data100[3] / 100, data100[3] % 100,
data100[4] / 100, data100[4] % 100,
data100[5] / 100, data100[5] % 100,
data100[6] / 100, data100[6] % 100,
data100[7] / 100, data100[7] % 100,
data100[8] / 100, data100[8] % 100,
data100[9] / 100, data100[9] % 100);
if (length > buflen)
{
length = buflen;
}
}
nxsem_post(&priv->devsem);
return length;
}
/****************************************************************************
* Name: sps30_write
****************************************************************************/
static ssize_t sps30_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
return -ENOSYS;
}
/****************************************************************************
* Name: sps30_ioctl
****************************************************************************/
static int sps30_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode = filep->f_inode;
FAR struct sps30_dev_s *priv = inode->i_private;
struct sps30_word_s param;
int ret;
/* Get exclusive access */
do
{
ret = nxsem_wait(&priv->devsem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
if (priv->unlinked)
{
/* Do not allow operations on unlinked sensors. This allows
* sensor use on hot swappable I2C bus.
*/
nxsem_post(&priv->devsem);
return -ENODEV;
}
#endif
switch (cmd)
{
/* Soft reset the SPS30, Arg: None */
case SNIOC_RESET:
{
ret = sps30_softreset(priv);
sps30_dbg("softreset ret: %d\n", ret);
sps30_configure(priv, priv->started);
}
break;
/* Start background measurement, Arg: None */
case SNIOC_START:
{
/* Start measurements (and set pressure compensation). */
sps30_set_command_param(&param, SPS30_MEASUREMENT_MODE);
ret = sps30_write_cmd(priv, SPS30_CMD_START_MEASUREMENT, &param, 1);
if (ret >= 0)
{
priv->started = true;
}
}
break;
/* Stop background measurement, Arg: None */
case SNIOC_STOP:
{
/* Stop measurements. */
ret = sps30_write_cmd(priv, SPS30_CMD_STOP_MEASUREMENT, NULL, 0);
if (ret >= 0)
{
priv->started = false;
}
}
break;
/* Set fan auto cleaning interval measurement interval, Arg: uint32_t */
case SNIOC_SET_CLEAN_INTERVAL:
{
if (arg != (uint32_t)arg)
{
ret = -EINVAL;
break;
}
if (arg > 0 && arg < 15)
{
arg = 15;
}
sps30_set_command_param(&param, arg);
ret = sps30_write_cmd(priv, SPS30_CMD_SET_AUTO_CLEANING_INTERVAL,
&param, 1);
}
break;
/* Start fan cleaning, Arg: None */
case SNIOC_START_FAN_CLEANING:
{
if (!priv->started)
{
ret = -EBUSY;
break;
}
ret = sps30_write_cmd(priv, SPS30_CMD_START_FAN_CLEANING, NULL, 0);
}
break;
/* Read sensor data, Arg: struct sps30_conv_data_s *data */
case SNIOC_READ_CONVERT_DATA:
{
FAR struct sps30_conv_data_s *data =
(FAR struct sps30_conv_data_s *)arg;
ret = sps30_read_values(priv, data, false);
if (ret < 0)
{
sps30_dbg("cannot read data: %d\n", ret);
}
}
break;
default:
sps30_dbg("Unrecognized cmd: %d\n", cmd);
ret = -ENOTTY;
break;
}
nxsem_post(&priv->devsem);
return ret;
}
/****************************************************************************
* Name: sps30_unlink
****************************************************************************/
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
static int sps30_unlink(FAR struct inode *inode)
{
FAR struct sps30_dev_s *priv;
int ret;
DEBUGASSERT(inode != NULL && inode->i_private != NULL);
priv = (FAR struct sps30_dev_s *)inode->i_private;
/* Get exclusive access */
do
{
ret = nxsem_wait(&priv->devsem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
/* Are there open references to the driver data structure? */
if (priv->crefs <= 0)
{
nxsem_destroy(&priv->devsem);
kmm_free(priv);
return OK;
}
/* No... just mark the driver as unlinked and free the resources when
* the last client closes their reference to the driver.
*/
priv->unlinked = true;
nxsem_post(&priv->devsem);
return ret;
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
#ifdef CONFIG_SPS30_I2C
/****************************************************************************
* Name: sps30_register_i2c
*
* Description:
* Register the SPS30 character device as 'devpath'
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/particle0"
* i2c - An instance of the I2C interface to use to communicate with
* the SPS30
* addr - The I2C address of the SPS30. The I2C address of SPS30 is
* always 0x69.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int sps30_register_i2c(FAR const char *devpath, FAR struct i2c_master_s *i2c,
uint8_t addr)
{
FAR struct sps30_dev_s *priv;
int ret;
DEBUGASSERT(i2c != NULL);
DEBUGASSERT(addr == CONFIG_SPS30_ADDR);
DEBUGASSERT(sps30_crc_word(0xbeef) == 0x92);
/* Initialize the device structure */
priv = (FAR struct sps30_dev_s *)kmm_zalloc(sizeof(struct sps30_dev_s));
if (priv == NULL)
{
sps30_dbg("ERROR: Failed to allocate instance\n");
return -ENOMEM;
}
priv->i2c = i2c;
priv->addr = addr;
priv->started = false;
nxsem_init(&priv->devsem, 0, 1);
/* Register the character driver */
ret = register_driver(devpath, &g_sps30fops, 0666, priv);
if (ret < 0)
{
sps30_dbg("ERROR: Failed to register driver: %d\n", ret);
kmm_free(priv);
}
return ret;
}
#endif /* CONFIG_SPS30_I2C */
#endif /* CONFIG_SENSORS_SPS30 */