Add support for the Sensirion SHT4x temperature and humidity sensor family.
This driver implements `read`, `write`, `open`, `close` and `ioctl` interfaces to the SHT4X temperature and humidity sensor on an I2C bus. The read implementation is that of a character driver for easy debugging, while `ioctl` provides an interface to the sensor's raw data collection and heating functionality.
This commit is contained in:
Matteo Golin
Alan Carvalho de Assis
parent
8c2dd0152c
commit
1fba2ec0df
@ -68,6 +68,11 @@
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#include "rp2040_bmp280.h"
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#endif
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#ifdef CONFIG_SENSORS_SHT4X
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#include <nuttx/sensors/sht4x.h>
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#include "rp2040_i2c.h"
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#endif
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#ifdef CONFIG_SENSORS_MAX6675
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#include <nuttx/sensors/max6675.h>
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#include "rp2040_max6675.h"
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@ -491,6 +496,18 @@ int rp2040_common_bringup(void)
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}
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#endif
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#ifdef CONFIG_SENSORS_SHT4X
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/* Try to register SHT4X device as /dev/sht4x0 at I2C0. */
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ret = sht4x_register("/dev/sht4x0", rp2040_i2cbus_initialize(0),
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CONFIG_SHT4X_I2C_ADDR);
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if (ret < 0)
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{
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syslog(LOG_ERR, "ERROR: couldn't initialize SHT4x: %d\n", ret);
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}
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#endif
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#ifdef CONFIG_VIDEO_FB
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ret = fb_register(0, 0);
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if (ret < 0)
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@ -264,6 +264,10 @@ if(CONFIG_SENSORS)
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list(APPEND SRCS sht3x.c)
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endif()
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if(CONFIG_SENSORS_SHT4X)
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list(APPEND SRCS sht4x.c)
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endif()
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if(CONFIG_SENSORS_SPS30)
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list(APPEND SRCS sps30.c)
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endif()
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@ -1499,6 +1499,54 @@ config SHT3X_DEBUG
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endif # SENSORS_SHT3X
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config SENSORS_SHT4X
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bool "Sensirion SHT4x temperature and humidity sensor"
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default n
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select I2C
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---help---
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Enable driver support for the Sensirion SHT4x temperature
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and humidity sensors.
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if SENSORS_SHT4X
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config SHT4X_I2C_FREQUENCY
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int "SHT4X I2C frequency"
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default 400000
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range 1 400000
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config SHT4X_I2C_ADDR
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hex "SHT4X I2C address"
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default 0x44
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range 0x44 0x46
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---help---
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Enables debug features for the SHT4X
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config SHT4X_FAHRENHEIT
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bool "SHT4X use Fahrenheit"
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default n
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---help---
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Configures read outputs of the SHT4X to be in Fahrenheit. Default uses Celsius.
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config SHT4X_LIMIT_HUMIDITY
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bool "SHT4X limit humidity between 0-100%"
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default y
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---help---
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Limits humidity calculations to be between 0-100 percent. Uncropped boundaries may be beneficial in some cases, see datasheet section 4.6.
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config SHT4X_CRC_LOOKUP
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bool "SHT4X use CRC lookup"
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default n
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---help---
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Configures the SHT4X to do CRC checks with a lookup table. Default uses a bitwise CRC calculation.
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config SHT4X_DEBUG
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bool "SHT4X debug support"
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default n
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---help---
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Enables debug features for the SHT4X
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endif # SENSORS_SHT4X
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config SENSORS_SPS30
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bool "Sensirion SPS30 particulate matter sensor"
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default n
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@ -277,6 +277,10 @@ ifeq ($(CONFIG_SENSORS_SHT3X),y)
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CSRCS += sht3x.c
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endif
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ifeq ($(CONFIG_SENSORS_SHT4X),y)
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CSRCS += sht4x.c
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endif
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ifeq ($(CONFIG_SENSORS_SPS30),y)
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CSRCS += sps30.c
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endif
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855
drivers/sensors/sht4x.c
Normal file
855
drivers/sensors/sht4x.c
Normal file
@ -0,0 +1,855 @@
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/****************************************************************************
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* drivers/sensors/sht4x.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <debug.h>
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#include <nuttx/clock.h>
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#include <nuttx/config.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/i2c/i2c_master.h>
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#include <nuttx/kmalloc.h>
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#include <nuttx/mutex.h>
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#include <nuttx/random.h>
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#include <nuttx/sensors/sht4x.h>
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#include <stdio.h>
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#include <unistd.h>
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#if defined(CONFIG_I2C) && defined(CONFIG_SENSORS_SHT4X)
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/****************************************************************************
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* Pre-processor Definitions
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****************************************************************************/
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#ifdef CONFIG_SHT4X_DEBUG
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#define sht4x_dbg(x, ...) _info(x, ##__VA_ARGS__)
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#endif
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#if defined(CONFIG_SHT4X_FAHRENHEIT)
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#define SHT4X_TEMP_UNIT "F"
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#else
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#define SHT4X_TEMP_UNIT "C"
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#endif // defined(CONFIG_SHT4X_FAHRENHEIT)
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#ifndef CONFIG_SHT4X_I2C_FREQUENCY
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#define CONFIG_SHT4X_I2C_FREQUENCY 400000
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#endif // CONFIG_SHT4X_I2C_FREQUENCY
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#define SHT4X_CRC_INIT 0xFF /* Initial value of the calculated CRC. */
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#define SHT4X_CRC_POLY 0x31 /* CRC calculation polynomial. */
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#define SHT4X_SOFT_RESET 0x94 /* Soft reset command. */
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#define SHT4X_READ_SERIAL 0x89 /* Read serial number command. */
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#define SHT4X_READ_LOW_PREC 0xE0 /* Low precision read temp & humidity. */
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#define SHT4X_READ_MED_PREC 0xF6 /* Med precision read temp & humidity. */
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#define SHT4X_READ_HIGH_PREC 0xFD /* High precision read temp & humidity. */
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#define SHT4X_HEAT_200_1 0x39 /* Activate heater with 200mW for 1s. */
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#define SHT4X_HEAT_200_P1 0x32 /* Activate heater with 200mW for 0.1s. */
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#define SHT4X_HEAT_110_1 0x2F /* Activate heater with 110mW for 1s. */
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#define SHT4X_HEAT_110_P1 0x24 /* Activate heater with 110mW for 0.1s. */
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#define SHT4X_HEAT_20_1 0x1E /* Activate heater with 20mW for 1s. */
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#define SHT4X_HEAT_20_P1 0x15 /* Activate heater with 20mW for 0.1s. */
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/****************************************************************************
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* Private
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****************************************************************************/
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struct sht4x_dev_s
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{
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FAR struct i2c_master_s *i2c; /* I2C interface. */
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uint8_t addr; /* I2C address. */
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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bool unlinked; /* True, driver has been unlinked. */
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#endif // CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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struct timespec last_heat; /* Last time heater was active. */
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enum sht4x_precision_e precision; /* The precision for read operations. */
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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int16_t crefs; /* Number of open references. */
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#endif // CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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mutex_t devlock;
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};
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/* Easy unpacking of serial number from I2C packet. */
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union sht4x_serialno_t
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{
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uint32_t full; /* Full serial number. */
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struct
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{
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uint16_t msb; /* Most significant 2 bytes. */
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uint16_t lsb; /* Least significant 2 bytes. */
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} halves;
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};
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/****************************************************************************
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* Private Data
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****************************************************************************/
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/* Commands for reading at different precisions */
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static const uint8_t g_precision_read[] =
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{
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[SHT4X_PREC_LOW] = SHT4X_READ_LOW_PREC,
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[SHT4X_PREC_MED] = SHT4X_READ_MED_PREC,
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[SHT4X_PREC_HIGH] = SHT4X_READ_HIGH_PREC,
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};
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#ifdef CONFIG_SHT4X_CRC_LOOKUP
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/* CRC lookup table. */
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static const uint8_t g_crc_lookup[] =
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{
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0x0, 0x31, 0x62, 0x53, 0xc4, 0xf5, 0xa6, 0x97, 0xb9, 0x88, 0xdb,
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0xea, 0x7d, 0x4c, 0x1f, 0x2e, 0x43, 0x72, 0x21, 0x10, 0x87, 0xb6,
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0xe5, 0xd4, 0xfa, 0xcb, 0x98, 0xa9, 0x3e, 0xf, 0x5c, 0x6d, 0x86,
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0xb7, 0xe4, 0xd5, 0x42, 0x73, 0x20, 0x11, 0x3f, 0xe, 0x5d, 0x6c,
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0xfb, 0xca, 0x99, 0xa8, 0xc5, 0xf4, 0xa7, 0x96, 0x1, 0x30, 0x63,
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0x52, 0x7c, 0x4d, 0x1e, 0x2f, 0xb8, 0x89, 0xda, 0xeb, 0x3d, 0xc,
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0x5f, 0x6e, 0xf9, 0xc8, 0x9b, 0xaa, 0x84, 0xb5, 0xe6, 0xd7, 0x40,
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0x71, 0x22, 0x13, 0x7e, 0x4f, 0x1c, 0x2d, 0xba, 0x8b, 0xd8, 0xe9,
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0xc7, 0xf6, 0xa5, 0x94, 0x3, 0x32, 0x61, 0x50, 0xbb, 0x8a, 0xd9,
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0xe8, 0x7f, 0x4e, 0x1d, 0x2c, 0x2, 0x33, 0x60, 0x51, 0xc6, 0xf7,
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0xa4, 0x95, 0xf8, 0xc9, 0x9a, 0xab, 0x3c, 0xd, 0x5e, 0x6f, 0x41,
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0x70, 0x23, 0x12, 0x85, 0xb4, 0xe7, 0xd6, 0x7a, 0x4b, 0x18, 0x29,
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0xbe, 0x8f, 0xdc, 0xed, 0xc3, 0xf2, 0xa1, 0x90, 0x7, 0x36, 0x65,
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0x54, 0x39, 0x8, 0x5b, 0x6a, 0xfd, 0xcc, 0x9f, 0xae, 0x80, 0xb1,
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0xe2, 0xd3, 0x44, 0x75, 0x26, 0x17, 0xfc, 0xcd, 0x9e, 0xaf, 0x38,
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0x9, 0x5a, 0x6b, 0x45, 0x74, 0x27, 0x16, 0x81, 0xb0, 0xe3, 0xd2,
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0xbf, 0x8e, 0xdd, 0xec, 0x7b, 0x4a, 0x19, 0x28, 0x6, 0x37, 0x64,
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0x55, 0xc2, 0xf3, 0xa0, 0x91, 0x47, 0x76, 0x25, 0x14, 0x83, 0xb2,
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0xe1, 0xd0, 0xfe, 0xcf, 0x9c, 0xad, 0x3a, 0xb, 0x58, 0x69, 0x4,
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0x35, 0x66, 0x57, 0xc0, 0xf1, 0xa2, 0x93, 0xbd, 0x8c, 0xdf, 0xee,
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0x79, 0x48, 0x1b, 0x2a, 0xc1, 0xf0, 0xa3, 0x92, 0x5, 0x34, 0x67,
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0x56, 0x78, 0x49, 0x1a, 0x2b, 0xbc, 0x8d, 0xde, 0xef, 0x82, 0xb3,
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0xe0, 0xd1, 0x46, 0x77, 0x24, 0x15, 0x3b, 0xa, 0x59, 0x68, 0xff,
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0xce, 0x9d, 0xac,
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}
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#endif // CONFIG_SHT4X_CRC_LOOKUP
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/* Measurement times for the various precisions, in microseconds. */
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static const uint16_t g_measurement_times[] =
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{
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[SHT4X_PREC_LOW] = 1600,
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[SHT4X_PREC_MED] = 4500,
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[SHT4X_PREC_HIGH] = 8300,
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};
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/* Commands for the various heating options. */
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static const uint8_t g_heat_cmds[] =
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{
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[SHT4X_HEATER_200MW_1] = SHT4X_HEAT_200_1,
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[SHT4X_HEATER_200MW_01] = SHT4X_HEAT_200_P1,
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[SHT4X_HEATER_110MW_1] = SHT4X_HEAT_110_1,
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[SHT4X_HEATER_110MW_01] = SHT4X_HEAT_110_P1,
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[SHT4X_HEATER_20MW_1] = SHT4X_HEAT_20_1,
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[SHT4X_HEATER_20MW_01] = SHT4X_HEAT_20_P1,
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};
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/* Timeouts for the various heating options in microseconds. */
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static const uint32_t g_heat_times[] =
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{
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[SHT4X_HEATER_200MW_1] = 1000000, [SHT4X_HEATER_200MW_01] = 100000,
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[SHT4X_HEATER_110MW_1] = 1000000, [SHT4X_HEATER_110MW_01] = 100000,
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[SHT4X_HEATER_20MW_1] = 1000000, [SHT4X_HEATER_20MW_01] = 100000,
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};
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/****************************************************************************
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* Private Function Prototypes
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****************************************************************************/
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static int sht4x_open(FAR struct file *filep);
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static int sht4x_close(FAR struct file *filep);
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static ssize_t sht4x_write(FAR struct file *filep, FAR const char *buffer,
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size_t buflen);
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static ssize_t sht4x_read(FAR struct file *filep, FAR char *buffer,
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size_t buflen);
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static int sht4x_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
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static int sht4x_unlink(FAR struct inode *inode);
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/****************************************************************************
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* Private Data
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****************************************************************************/
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static const struct file_operations g_sht4xfops =
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{
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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.open = sht4x_open,
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.close = sht4x_close,
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#else
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.open = NULL,
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.close = NULL,
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#endif
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.read = sht4x_read,
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.write = sht4x_write,
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.seek = NULL,
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.ioctl = sht4x_ioctl,
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.mmap = NULL,
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.truncate = NULL,
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.poll = NULL,
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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.unlink = sht4x_unlink,
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#endif
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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#ifdef CONFIG_SHT4X_CRC_LOOKUP
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/****************************************************************************
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* Name: sht4x_crc_lookup
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*
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* Description:
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* Perform a CRC calculation using the lookup table.
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*
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****************************************************************************/
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uint8_t sht4x_crc_lookup(const uint8_t *buf, uint8_t nbytes)
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{
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uint8_t crc = SHT4X_CRC_INIT;
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for (uint8_t byte = 0; byte < nbytes; byte++)
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{
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crc = g_crc_lookup[crc ^ buf[byte]];
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}
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return crc;
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}
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#endif
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/****************************************************************************
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* Name: sht4x_crc_bitwise
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*
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* Description:
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* Perform a CRC calculation using the bitwise calculation.
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*
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****************************************************************************/
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uint8_t sht4x_crc_bitwise(const uint8_t *buf, uint8_t nbytes)
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{
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uint8_t crc = SHT4X_CRC_INIT;
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for (uint8_t byte = 0; byte < nbytes; byte++)
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{
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crc ^= buf[byte];
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for (uint8_t bit = 0; bit < 8; bit++)
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{
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if (crc & 0x80)
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{
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/* Discard the highest bit (implicit XOR), then divide by the
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* polynomial.
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*/
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crc <<= 1;
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crc ^= SHT4X_CRC_POLY;
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}
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else
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{
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/* Continue until the highest bit is set. */
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crc <<= 1;
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}
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}
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}
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return crc;
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}
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/****************************************************************************
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* Name: sht4x_crc
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*
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* Description:
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* Perform a CRC calculation on the data to check for validity.
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* The `buf` param must be a data buffer that ends with its own 8 bit CRC.
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* The `nbytes` param is the length of the data including the 8 bit CRC.
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*
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****************************************************************************/
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static int sht4x_crc(const uint8_t *buf, uint8_t nbytes)
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{
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#ifdef CONFIG_SHT4X_CRC_LOOKUP
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if (sht4x_crc_lookup(buf, nbytes) != 0)
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{
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return -EBADMSG;
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}
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#else
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if (sht4x_crc_bitwise(buf, nbytes) != 0)
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{
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return -EBADMSG;
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}
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#endif
|
||||
return 0;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_cmd
|
||||
*
|
||||
* Description:
|
||||
* I2C access helper for sending commands to the SHT4x which receive data
|
||||
* in response.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
static int sht4x_cmd(FAR struct sht4x_dev_s *priv, uint8_t command,
|
||||
uint32_t timeout, uint16_t *data1, uint16_t *data2)
|
||||
{
|
||||
struct i2c_msg_s cmd;
|
||||
struct i2c_msg_s read_data;
|
||||
int err;
|
||||
|
||||
/* 2 byte data, 1 byte CRC, 2 byte data, 1 byte CRC. */
|
||||
|
||||
uint8_t combined_data[6];
|
||||
|
||||
cmd.frequency = CONFIG_SHT4X_I2C_FREQUENCY;
|
||||
cmd.addr = priv->addr;
|
||||
cmd.flags = 0;
|
||||
cmd.buffer = &command;
|
||||
cmd.length = sizeof(command);
|
||||
|
||||
/* Trigger measurement. */
|
||||
|
||||
err = I2C_TRANSFER(priv->i2c, &cmd, 1);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Wait for measurement to complete. Serial number command does not require
|
||||
* wait time.
|
||||
*/
|
||||
|
||||
if (timeout > 0)
|
||||
{
|
||||
usleep(timeout);
|
||||
}
|
||||
|
||||
read_data.frequency = CONFIG_SHT4X_I2C_FREQUENCY;
|
||||
read_data.addr = priv->addr;
|
||||
read_data.flags = I2C_M_READ;
|
||||
read_data.buffer = combined_data;
|
||||
read_data.length = sizeof(combined_data);
|
||||
|
||||
err = I2C_TRANSFER(priv->i2c, &read_data, 1);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Check CRC for first data packet */
|
||||
|
||||
err = sht4x_crc(combined_data, 3);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Check CRC for second data packet */
|
||||
|
||||
err = sht4x_crc(combined_data + 3, 3);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
*data1 = (uint16_t)(combined_data[0] << 8) | combined_data[1];
|
||||
*data2 = (uint16_t)(combined_data[3] << 8) | combined_data[4];
|
||||
return err;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_reset
|
||||
*
|
||||
* Description:
|
||||
* Perform a soft reset of the sensor. WARNING: Sensor is not available
|
||||
* until 1ms after this command is sent.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
static int sht4x_reset(FAR struct sht4x_dev_s *priv)
|
||||
{
|
||||
struct i2c_msg_s msg[1];
|
||||
uint8_t reset_cmd = SHT4X_SOFT_RESET;
|
||||
|
||||
msg[0].frequency = CONFIG_SHT4X_I2C_FREQUENCY;
|
||||
msg[0].addr = priv->addr;
|
||||
msg[0].flags = 0;
|
||||
msg[0].buffer = &reset_cmd;
|
||||
msg[0].length = sizeof(reset_cmd);
|
||||
|
||||
return I2C_TRANSFER(priv->i2c, msg, 1);
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_calc_temp
|
||||
*
|
||||
* Description:
|
||||
* Calculate the temperature from the SHT4X raw data.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
static int32_t sht4x_calc_temp(uint16_t temp)
|
||||
{
|
||||
#ifdef CONFIG_SHT4X_FAHRENHEIT
|
||||
/* Millidegrees Fahrenheit */
|
||||
|
||||
return -49000 + 315 * ((temp * 1000) / 65535);
|
||||
#else
|
||||
return -45000 + 175 * ((temp * 1000) / 65535); /* Millidegrees Celsius */
|
||||
#endif // CONFIG_SHT4X_FAHRENHEIT
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_calc_hum
|
||||
*
|
||||
* Description:
|
||||
* Calculate the humidity from the SHT4X raw data.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
static int16_t sht4x_calc_hum(uint16_t humidity)
|
||||
{
|
||||
int16_t hum = -600 + 125 * ((humidity * 100) / 65535); /* 0.01 %RH */
|
||||
#ifdef CONFIG_SHT4X_LIMIT_HUMIDITY
|
||||
|
||||
/* Limit values of humidity, since values outside of 0-100 are invalid. */
|
||||
|
||||
if (hum < 0)
|
||||
{
|
||||
hum = 0;
|
||||
}
|
||||
else if (hum > 10000)
|
||||
{
|
||||
hum = 10000;
|
||||
}
|
||||
|
||||
#endif // CONFIG_SHT4X_LIMIT_HUMIDITY
|
||||
return hum;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* 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: sht4x_open
|
||||
*
|
||||
* Description:
|
||||
* This function is called whenever the SHT4X device is opened.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
||||
static int sht4x_open(FAR struct file *filep)
|
||||
{
|
||||
FAR struct inode *inode = filep->f_inode;
|
||||
FAR struct sht4x_dev_s *priv = inode->i_private;
|
||||
int err;
|
||||
|
||||
err = nxmutex_lock(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Increment the count of open references on the driver */
|
||||
|
||||
priv->crefs++;
|
||||
DEBUGASSERT(priv->crefs > 0);
|
||||
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_close
|
||||
*
|
||||
* Description:
|
||||
* This routine is called when the SHT4X device is closed.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
||||
static int sht4x_close(FAR struct file *filep)
|
||||
{
|
||||
FAR struct inode *inode = filep->f_inode;
|
||||
FAR struct sht4x_dev_s *priv = inode->i_private;
|
||||
int err;
|
||||
|
||||
err = nxmutex_lock(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* 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)
|
||||
{
|
||||
nxmutex_destroy(&priv->devlock);
|
||||
kmm_free(priv);
|
||||
return 0;
|
||||
}
|
||||
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_read
|
||||
*
|
||||
* Description:
|
||||
* Character driver interface to sensor for debugging.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
static ssize_t sht4x_read(FAR struct file *filep, FAR char *buffer,
|
||||
size_t buflen)
|
||||
{
|
||||
FAR struct inode *inode = filep->f_inode;
|
||||
FAR struct sht4x_dev_s *priv = inode->i_private;
|
||||
ssize_t length = 0;
|
||||
struct sht4x_raw_data_s raw_data;
|
||||
struct sht4x_conv_data_s data;
|
||||
int err;
|
||||
|
||||
/* If file position is non-zero, then we're at the end of file. */
|
||||
|
||||
if (filep->f_pos > 0) return 0;
|
||||
|
||||
/* Get exclusive access */
|
||||
|
||||
err = nxmutex_lock(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
||||
if (priv->unlinked)
|
||||
{
|
||||
/* Do not allow operations on unlinked sensors. This allows
|
||||
* sensor use on hot swappable I2C bus.
|
||||
*/
|
||||
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
err = sht4x_cmd(priv, g_precision_read[priv->precision],
|
||||
g_measurement_times[priv->precision], &raw_data.raw_temp,
|
||||
&raw_data.raw_hum);
|
||||
if (err < 0)
|
||||
{
|
||||
#ifdef CONFIG_SHT4X_DEBUG
|
||||
sht4x_dbg("Could not read device: %d\n", err);
|
||||
#endif // CONFIG_SHT4X_DEBUG
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Convert to proper units. */
|
||||
|
||||
data.temp = sht4x_calc_temp(raw_data.raw_temp);
|
||||
data.hum = sht4x_calc_hum(raw_data.raw_hum);
|
||||
|
||||
length = snprintf(buffer, buflen, "%ld m" SHT4X_TEMP_UNIT ", %d %%RH\n",
|
||||
data.temp, data.hum / 100);
|
||||
if (length > buflen) length = buflen;
|
||||
|
||||
filep->f_pos += length;
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return length;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_write
|
||||
*
|
||||
* Description:
|
||||
* Not implemented.
|
||||
****************************************************************************/
|
||||
|
||||
static ssize_t sht4x_write(FAR struct file *filep, FAR const char *buffer,
|
||||
size_t buflen)
|
||||
{
|
||||
return -ENOSYS;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_ioctl
|
||||
****************************************************************************/
|
||||
|
||||
static int sht4x_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
|
||||
{
|
||||
FAR struct inode *inode = filep->f_inode;
|
||||
FAR struct sht4x_dev_s *priv = inode->i_private;
|
||||
int err;
|
||||
|
||||
err = nxmutex_lock(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
||||
if (priv->unlinked)
|
||||
{
|
||||
/* Do not allow operations on unlinked sensors. This allows
|
||||
* sensor use on hot swappable I2C bus.
|
||||
*/
|
||||
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return -ENODEV;
|
||||
}
|
||||
#endif
|
||||
|
||||
switch (cmd)
|
||||
{
|
||||
case SNIOC_RESET:
|
||||
err = sht4x_reset(priv);
|
||||
break;
|
||||
|
||||
case SNIOC_WHO_AM_I:
|
||||
{
|
||||
union sht4x_serialno_t serialno;
|
||||
err = sht4x_cmd(priv, SHT4X_READ_SERIAL, 10, &serialno.halves.msb,
|
||||
&serialno.halves.lsb);
|
||||
*((uint32_t *)(arg)) = serialno.full;
|
||||
}
|
||||
break;
|
||||
|
||||
case SNIOC_READ_RAW_DATA:
|
||||
err = sht4x_cmd(priv, g_precision_read[priv->precision],
|
||||
g_measurement_times[priv->precision],
|
||||
&((struct sht4x_raw_data_s *)(arg))->raw_temp,
|
||||
&((struct sht4x_raw_data_s *)(arg))->raw_hum);
|
||||
break;
|
||||
|
||||
case SNIOC_MEASURE:
|
||||
case SNIOC_READ_CONVERT_DATA:
|
||||
{
|
||||
uint16_t raw_t;
|
||||
uint16_t raw_h;
|
||||
|
||||
err = sht4x_cmd(priv, g_precision_read[priv->precision],
|
||||
g_measurement_times[priv->precision],
|
||||
&raw_t, &raw_h);
|
||||
((struct sht4x_conv_data_s *)(arg))->temp = sht4x_calc_temp(raw_t);
|
||||
((struct sht4x_conv_data_s *)(arg))->hum = sht4x_calc_hum(raw_h);
|
||||
}
|
||||
break;
|
||||
|
||||
case SNIOC_HEAT:
|
||||
{
|
||||
struct timespec now;
|
||||
clock_systime_timespec(&now);
|
||||
|
||||
/* Check if it has been one second since the last heat command. */
|
||||
|
||||
if (!has_time_passed(now, priv->last_heat, 1))
|
||||
{
|
||||
err = -EAGAIN; /* Signal to try again in some time. */
|
||||
break;
|
||||
}
|
||||
|
||||
/* Caller must pass heater option in the temperature argument. */
|
||||
|
||||
uint16_t raw_t = ((struct sht4x_conv_data_s *)(arg))->temp;
|
||||
uint16_t raw_h;
|
||||
|
||||
err = sht4x_cmd(priv, g_heat_cmds[raw_t], g_heat_times[raw_t],
|
||||
&raw_t, &raw_h);
|
||||
((struct sht4x_conv_data_s *)(arg))->temp = sht4x_calc_temp(raw_t);
|
||||
((struct sht4x_conv_data_s *)(arg))->hum = sht4x_calc_hum(raw_h);
|
||||
clock_systime_timespec(&priv->last_heat); /* Update last heat time. */
|
||||
}
|
||||
break;
|
||||
|
||||
case SNIOC_CONFIGURE:
|
||||
|
||||
/* Caller must pass precision option as argument. */
|
||||
|
||||
priv->precision = arg;
|
||||
#ifdef CONFIG_SHT4X_DEBUG
|
||||
sht4x_dbg("Precision set to %d\n", priv->precision);
|
||||
#endif // CONFIG_SHT4X_DEBUG
|
||||
|
||||
break;
|
||||
|
||||
default:
|
||||
err = -EINVAL;
|
||||
break;
|
||||
}
|
||||
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return err;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_unlink
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
|
||||
static int sht4x_unlink(FAR struct inode *inode)
|
||||
{
|
||||
FAR struct sht4x_dev_s *priv;
|
||||
int err;
|
||||
|
||||
DEBUGASSERT(inode->i_private != NULL);
|
||||
priv = inode->i_private;
|
||||
|
||||
err = nxmutex_lock(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Are there open references to the driver data structure? */
|
||||
|
||||
if (priv->crefs <= 0)
|
||||
{
|
||||
nxmutex_destroy(&priv->devlock);
|
||||
kmm_free(priv);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* No. Just mark the driver as unlinked and free the resources when
|
||||
* the last client closes their reference to the driver.
|
||||
*/
|
||||
|
||||
priv->unlinked = true;
|
||||
nxmutex_unlock(&priv->devlock);
|
||||
return OK;
|
||||
}
|
||||
#endif
|
||||
|
||||
/****************************************************************************
|
||||
* Public Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_register
|
||||
*
|
||||
* Description:
|
||||
* Register the SHT4X character device as 'devpath'
|
||||
*
|
||||
* Input Parameters:
|
||||
* devpath - The full path to the driver to register. E.g., "/dev/temp0"
|
||||
* i2c - An instance of the I2C interface to use to communicate with
|
||||
* the SHT4X
|
||||
* addr - The I2C address of the SHT4X. The I2C address is one of 0x44,
|
||||
*0x45 and 0x46.
|
||||
*
|
||||
* Returned Value:
|
||||
* Zero (OK) on success; a negated errno value on failure.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int sht4x_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
|
||||
uint8_t addr)
|
||||
{
|
||||
FAR struct sht4x_dev_s *priv;
|
||||
int err;
|
||||
|
||||
DEBUGASSERT(i2c != NULL);
|
||||
DEBUGASSERT(addr == 0x44 || addr == 0x45 || addr == 0x46);
|
||||
|
||||
/* Initialize the device structure */
|
||||
|
||||
priv = kmm_zalloc(sizeof(struct sht4x_dev_s));
|
||||
if (priv == NULL)
|
||||
{
|
||||
snerr("ERROR: Failed to allocate instance.\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
priv->i2c = i2c;
|
||||
priv->addr = addr;
|
||||
priv->precision = SHT4X_PREC_HIGH;
|
||||
err = clock_systime_timespec(&priv->last_heat);
|
||||
|
||||
if (err < 0)
|
||||
{
|
||||
snerr("ERROR: Failed to get timespec: %d\n", err);
|
||||
kmm_free(priv);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Allow heat immediately after registration since in theory the sensor has
|
||||
* never had its heater activated yet.
|
||||
*/
|
||||
|
||||
priv->last_heat.tv_sec -= 1;
|
||||
|
||||
err = nxmutex_init(&priv->devlock);
|
||||
if (err < 0)
|
||||
{
|
||||
snerr("ERROR: Failed to register SHT4X driver: %d\n", err);
|
||||
kmm_free(priv);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Register the character driver */
|
||||
|
||||
err = register_driver(devpath, &g_sht4xfops, 0666, priv);
|
||||
if (err < 0)
|
||||
{
|
||||
snerr("ERROR: Failed to register SHT4X driver: %d\n", err);
|
||||
nxmutex_destroy(&priv->devlock);
|
||||
kmm_free(priv);
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_I2C && CONFIG_SENSORS_SHT4X */
|
||||
@ -406,4 +406,11 @@
|
||||
|
||||
#define SNIOC_ENABLE_FIFO _SNIOC(0x009A)
|
||||
|
||||
/* Command: SNIOC_HEAT
|
||||
* Description: Turn on the heater.
|
||||
* Argument: Heater configuration.
|
||||
*/
|
||||
|
||||
#define SNIOC_HEAT _SNIOC(0x009B)
|
||||
|
||||
#endif /* __INCLUDE_NUTTX_SENSORS_IOCTL_H */
|
||||
|
||||
94
include/nuttx/sensors/sht4x.h
Normal file
94
include/nuttx/sensors/sht4x.h
Normal file
@ -0,0 +1,94 @@
|
||||
/****************************************************************************
|
||||
* include/nuttx/sensors/sht4x.h
|
||||
*
|
||||
* Licensed to the Apache Software Foundation (ASF) under one or more
|
||||
* contributor license agreements. See the NOTICE file distributed with
|
||||
* this work for additional information regarding copyright ownership. The
|
||||
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
||||
* "License"); you may not use this file except in compliance with the
|
||||
* License. You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
||||
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
||||
* License for the specific language governing permissions and limitations
|
||||
* under the License.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef __INCLUDE_NUTTX_SENSORS_SHT4X_H
|
||||
#define __INCLUDE_NUTTX_SENSORS_SHT4X_H
|
||||
|
||||
/****************************************************************************
|
||||
* Included Files
|
||||
****************************************************************************/
|
||||
|
||||
#include <nuttx/sensors/ioctl.h>
|
||||
|
||||
/****************************************************************************
|
||||
* Public Types
|
||||
****************************************************************************/
|
||||
|
||||
struct i2c_master_s; /* Forward reference */
|
||||
|
||||
struct sht4x_conv_data_s
|
||||
{
|
||||
int32_t temp; /* Millidegrees Celsius or Fahrenheit (depending on config) */
|
||||
int16_t hum; /* Percentage relative humidity in units of 0.01 %RH */
|
||||
};
|
||||
|
||||
struct sht4x_raw_data_s
|
||||
{
|
||||
uint16_t raw_temp;
|
||||
uint16_t raw_hum;
|
||||
};
|
||||
|
||||
/* Precision for reading. */
|
||||
|
||||
enum sht4x_precision_e
|
||||
{
|
||||
SHT4X_PREC_LOW = 0, /* Low precision. */
|
||||
SHT4X_PREC_MED = 1, /* Medium precision. */
|
||||
SHT4X_PREC_HIGH = 2, /* High precision. */
|
||||
};
|
||||
|
||||
/* Durations and power for heating. */
|
||||
|
||||
enum sht4x_heater_e
|
||||
{
|
||||
SHT4X_HEATER_200MW_1 = 0, /* Activate heater with 200mW for 1s. */
|
||||
SHT4X_HEATER_200MW_01 = 1, /* Activate heater with 200mW for 0.1s. */
|
||||
SHT4X_HEATER_110MW_1 = 2, /* Activate heater with 110mW for 1s. */
|
||||
SHT4X_HEATER_110MW_01 = 3, /* Activate heater with 110mW for 0.1s. */
|
||||
SHT4X_HEATER_20MW_1 = 4, /* Activate heater with 20mW for 1s. */
|
||||
SHT4X_HEATER_20MW_01 = 5, /* Activate heater with 20mW for 0.1s. */
|
||||
};
|
||||
|
||||
/****************************************************************************
|
||||
* Public Function Prototypes
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sht4x_register
|
||||
*
|
||||
* Description:
|
||||
* Register the SHT4X character device as 'devpath'
|
||||
*
|
||||
* Input Parameters:
|
||||
* devpath - The full path to the driver to register. E.g., "/dev/temp0"
|
||||
* i2c - An instance of the I2C interface to use to communicate with
|
||||
* the SHT4X
|
||||
* addr - The I2C address of the SHT4X. The I2C address is one of 0x44,
|
||||
* 0x45 and 0x46.
|
||||
*
|
||||
* Returned Value:
|
||||
* Zero (OK) on success; a negated errno value on failure.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int sht4x_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
|
||||
uint8_t addr);
|
||||
|
||||
#endif /* __INCLUDE_NUTTX_SENSORS_SHT4X_H */
|
||||
Loading…
Reference in New Issue
Block a user