/**************************************************************************** * drivers/sensors/adt7320.c * * 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "adt7320.h" #if defined(CONFIG_SPI) && defined(CONFIG_SENSORS_ADT7320) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #ifndef CONFIG_ADT7320_SPI_FREQUENCY # define CONFIG_ADT7320_SPI_FREQUENCY 1000000 #endif #define ADT7320_SPI_MODE (SPIDEV_MODE3) /* SPI Mode 3: CPOL=1,CPHA=1 */ /* Centigrade to Fahrenheit conversion: F = 9*C/5 + 32 */ #define B16_9DIV5 (9 * 65536 / 5) #define B16_32 (32 * 65536) /**************************************************************************** * Private ****************************************************************************/ struct adt7320_dev_s { FAR struct spi_dev_s *spi; /* Saved SPI driver instance */ int spidev; bool fahrenheit; /* true: temperature will be reported in * fahrenheit */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* SPI Helpers */ static void adt7320_write_reg16(FAR struct adt7320_dev_s *priv, uint8_t reg, uint16_t data); static uint16_t adt7320_read_reg16(FAR struct adt7320_dev_s *priv, uint8_t reg); static void adt7320_write_reg8(FAR struct adt7320_dev_s *priv, uint8_t reg, uint8_t data); static uint8_t adt7320_read_reg8(FAR struct adt7320_dev_s *priv, uint8_t reg); static int adt7320_readtemp(FAR struct adt7320_dev_s *priv, FAR b16_t *temp); /* Character driver methods */ static int adt7320_open(FAR struct file *filep); static int adt7320_close(FAR struct file *filep); static ssize_t adt7320_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static ssize_t adt7320_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); static int adt7320_ioctl(FAR struct file *filep, int cmd, unsigned long arg); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations g_adt7320fops = { adt7320_open, adt7320_close, adt7320_read, adt7320_write, NULL, adt7320_ioctl, NULL }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: adt7320_configspi * * Description: * Configure the SPI interface to match the serial interface specification * of the ADT7320. * ****************************************************************************/ static inline void adt7320_configspi(FAR struct spi_dev_s *spi) { /* Configure SPI for the ADT7320 */ SPI_SETMODE(spi, ADT7320_SPI_MODE); SPI_SETBITS(spi, 8); SPI_HWFEATURES(spi, 0); SPI_SETFREQUENCY(spi, CONFIG_ADT7320_SPI_FREQUENCY); } /**************************************************************************** * Name: adt7320_write_reg16 * * Description: * Write to a 16-bit register (ADT7320_TEMP_REG, ADT7320_TCRIT_REG, * ADT7320_THIGH_REG or ADT7320_TLOW_REG). * ****************************************************************************/ static void adt7320_write_reg16(FAR struct adt7320_dev_s *priv, uint8_t reg, const uint16_t data) { SPI_LOCK(priv->spi, true); adt7320_configspi(priv->spi); SPI_SELECT(priv->spi, priv->spidev, true); SPI_SEND(priv->spi, (reg & 0x07) << 3); SPI_SEND(priv->spi, data >> 8); SPI_SEND(priv->spi, data & 0xff); SPI_SELECT(priv->spi, priv->spidev, false); SPI_LOCK(priv->spi, false); } /**************************************************************************** * Name: adt7320_read_reg16 * * Description: * Read a 16-bit register (ADT7320_TEMP_REG, ADT7320_TCRIT_REG, * ADT7320_THIGH_REG or ADT7320_TLOW_REG). * ****************************************************************************/ static uint16_t adt7320_read_reg16(FAR struct adt7320_dev_s *priv, uint8_t reg) { uint8_t data[2]; SPI_LOCK(priv->spi, true); adt7320_configspi(priv->spi); SPI_SELECT(priv->spi, priv->spidev, true); SPI_SEND(priv->spi, ((reg & 0x07) << 3) | (1 << 6)); SPI_RECVBLOCK(priv->spi, data, 2); SPI_SELECT(priv->spi, priv->spidev, false); SPI_LOCK(priv->spi, false); return (data[0] << 8) | data[1]; } /**************************************************************************** * Name: adt7320_write_reg8 * * Description: * Write to a 8-bit register (ADT7320_STAT_REG, ADT7320_TCRIT_REG, * ADT7320_CONF_REG, ADT7320_ID_REG or ADT7320_THYST_REG). ****************************************************************************/ static void adt7320_write_reg8(FAR struct adt7320_dev_s *priv, uint8_t reg, const uint8_t data) { SPI_LOCK(priv->spi, true); adt7320_configspi(priv->spi); SPI_SELECT(priv->spi, priv->spidev, true); SPI_SEND(priv->spi, (reg & 0x07) << 3); SPI_SEND(priv->spi, data); SPI_SELECT(priv->spi, priv->spidev, false); SPI_LOCK(priv->spi, false); } /**************************************************************************** * Name: adt7320_read_reg8 * * Description: * Read a 8-bit register (ADT7320_STAT_REG, ADT7320_TCRIT_REG, * ADT7320_CONF_REG, ADT7320_ID_REG or ADT7320_THYST_REG). ****************************************************************************/ static uint8_t adt7320_read_reg8(FAR struct adt7320_dev_s *priv, uint8_t reg) { uint8_t data; SPI_LOCK(priv->spi, true); adt7320_configspi(priv->spi); SPI_SELECT(priv->spi, priv->spidev, true); SPI_SEND(priv->spi, ((reg & 0x07) << 3) | (1 << 6)); SPI_RECVBLOCK(priv->spi, &data, 1); SPI_SELECT(priv->spi, priv->spidev, false); SPI_LOCK(priv->spi, false); return data; } /**************************************************************************** * Name: adt7320_reset * * Description: * Reset the ADT7320, you should wait at least 500us before trying to * access the sensor again. * ****************************************************************************/ static void adt7320_reset(FAR struct adt7320_dev_s *priv) { SPI_LOCK(priv->spi, true); adt7320_configspi(priv->spi); SPI_SELECT(priv->spi, priv->spidev, true); SPI_SEND(priv->spi, 0xff); SPI_SEND(priv->spi, 0xff); SPI_SEND(priv->spi, 0xff); SPI_SEND(priv->spi, 0xff); SPI_SELECT(priv->spi, priv->spidev, false); SPI_LOCK(priv->spi, false); } /**************************************************************************** * Name: adt7320_readtemp * * Description: * Read the temperature register with special scaling (ADT7320_TEMP_REG). * ****************************************************************************/ static int adt7320_readtemp(FAR struct adt7320_dev_s *priv, FAR b16_t *temp) { b16_t temp16; int16_t temp_raw; /* Read the raw temperature data (b16_t) */ temp_raw = (int16_t)adt7320_read_reg16(priv, ADT7320_TEMP_REG) & 0xfff8; /* Convert from 9.7 bits to 16.16 bits */ temp16 = (int32_t)temp_raw << 9; add_sensor_randomness(temp16); sninfo("Centigrade: %08x\n", temp16); /* Was fahrenheit requested? */ if (priv->fahrenheit) { /* Centigrade to Fahrenheit conversion: F = 9*C/5 + 32 */ temp16 = b16mulb16(temp16, B16_9DIV5) + B16_32; sninfo("Fahrenheit: %08x\n", temp16); } *temp = temp16; return OK; } /**************************************************************************** * Name: adt7320_open * * Description: * This function is called whenever the ADT7320 device is opened. * ****************************************************************************/ static int adt7320_open(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct adt7320_dev_s *priv = inode->i_private; if (adt7320_read_reg8(priv, ADT7320_ID_REG) != ADT7320_ID) { return -ENODEV; } return OK; } /**************************************************************************** * Name: adt7320_close * * Description: * This routine is called when the ADT7320 device is closed. * ****************************************************************************/ static int adt7320_close(FAR struct file *filep) { return OK; } /**************************************************************************** * Name: adt7320_read ****************************************************************************/ static ssize_t adt7320_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { FAR struct inode *inode = filep->f_inode; FAR struct adt7320_dev_s *priv = inode->i_private; FAR b16_t *ptr; ssize_t nsamples; int i; int ret; /* How many samples were requested to get? */ nsamples = buflen / sizeof(b16_t); ptr = (FAR b16_t *)buffer; sninfo("buflen: %d nsamples: %d\n", buflen, nsamples); /* Get the requested number of samples */ for (i = 0; i < nsamples; i++) { b16_t temp = 0; /* Read the next b16_t temperature value */ ret = adt7320_readtemp(priv, &temp); if (ret < 0) { snerr("ERROR: adt7320_readtemp failed: %d\n", ret); return (ssize_t)ret; } /* Save the temperature value in the user buffer */ *ptr++ = temp; } return nsamples * sizeof(b16_t); } /**************************************************************************** * Name: adt7320_write ****************************************************************************/ static ssize_t adt7320_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { return -ENOSYS; } /**************************************************************************** * Name: adt7320_ioctl * * Description: * Supported IOCTLs: * * SNIOC_READSTAT: Read the status register, treat arg as an * uint8_t pointer. * * SNIOC_READCONF: Read the configuration register, treat arg as * an uint8_t pointer. * * SNIOC_WRITECONF: Write to the configuration register, treat arg * as an uint8_t value. * * SNIOC_FAHRENHEIT: Report samples in Fahrenheit, ignores arg. * * SNIOC_CENTIGRADE: Report samples in Celsius, ignores arg. * * SNIOC_READTCRIT: Read the critical temperature register, treat * arg as an b16_t pointer. * * SNIOC_WRITETCRIT: Write to the critical temperature register, * treat arg as an b16_t value. * * SNIOC_READTHYS: Read the hysteresis temperature register, treat * arg as an b16_t pointer. * * SNIOC_WRITETHYS: Write to the hysteresis temperature register, * treat arg as an b16_t value. * * SNIOC_READTLOW: Read the low temperature register, treat arg as * an b16_t pointer. * * SNIOC_WRITETLOW: Write to the low temperature register, treat * arg as an b16_t value. * * SNIOC_READTHIGH: Read the high temperature register, treat arg * as an b16_t pointer. * * SNIOC_WRITETHIGH: Write to the high temperature register, treat * arg as an b16_t value. * ****************************************************************************/ static int adt7320_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct adt7320_dev_s *priv = inode->i_private; int ret = OK; switch (cmd) { /* Read the status register. Arg: uint8_t* pointer */ case SNIOC_READSTAT: { FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg); DEBUGASSERT(ptr != NULL); *ptr = adt7320_read_reg8(priv, ADT7320_STAT_REG); } break; /* Read the configuration register. Arg: uint8_t* pointer */ case SNIOC_READCONF: { FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg); DEBUGASSERT(ptr != NULL); *ptr = adt7320_read_reg8(priv, ADT7320_CONF_REG); } break; /* Write to the configuration register. Arg: uint8_t value */ case SNIOC_WRITECONF: adt7320_write_reg8(priv, ADT7320_CONF_REG, (uint8_t)arg); break; /* Report samples in Fahrenheit */ case SNIOC_FAHRENHEIT: priv->fahrenheit = true; sninfo("Fahrenheit\n"); break; /* Report samples in Celsius */ case SNIOC_CENTIGRADE: priv->fahrenheit = false; sninfo("Celsius\n"); break; /* Read the critical temperature register. Arg: b16_t* pointer */ case SNIOC_READTCRIT: { FAR b16_t *ptr = (FAR b16_t *)((uintptr_t)arg); int16_t temp_raw; DEBUGASSERT(ptr != NULL); temp_raw = adt7320_read_reg16(priv, ADT7320_TCRIT_REG); *ptr = b8tob16(temp_raw << 1); } break; /* Write to the critical temperature register. Arg: b16_t value */ case SNIOC_WRITETCRIT: adt7320_write_reg16(priv, ADT7320_TCRIT_REG, b16tob8((b16_t)arg) >> 1); break; /* Read the hysteresis temperature register. Arg: b16_t* */ case SNIOC_READTHYS: { FAR b16_t *ptr = (FAR b16_t *)((uintptr_t)arg); uint8_t tmp; DEBUGASSERT(ptr != NULL); tmp = adt7320_read_reg8(priv, ADT7320_THYST_REG); *ptr = uitoub16(tmp); } break; /* Write to the hysteresis temperature register. Arg: b16_t value */ case SNIOC_WRITETHYS: adt7320_write_reg8(priv, ADT7320_THYST_REG, ub16toi((b16_t)arg)); break; /* Read the low temperature register. Arg: b16_t* pointer */ case SNIOC_READTLOW: { FAR b16_t *ptr = (FAR b16_t *)((uintptr_t)arg); int16_t temp_raw; DEBUGASSERT(ptr != NULL); temp_raw = adt7320_read_reg16(priv, ADT7320_TLOW_REG); *ptr = b8tob16(temp_raw << 1); } break; /* Write to the low temperature register. Arg: b16_t value */ case SNIOC_WRITETLOW: adt7320_write_reg16(priv, ADT7320_TLOW_REG, b16tob8((b16_t)arg) >> 1); break; /* Read the high temperature register. Arg: b16_t* pointer */ case SNIOC_READTHIGH: { FAR b16_t *ptr = (FAR b16_t *)((uintptr_t)arg); int16_t temp_raw; DEBUGASSERT(ptr != NULL); temp_raw = adt7320_read_reg16(priv, ADT7320_THIGH_REG); *ptr = b8tob16(temp_raw << 1); } break; /* Write to the high temperature register. Arg: b16_t value */ case SNIOC_WRITETHIGH: adt7320_write_reg16(priv, ADT7320_THIGH_REG, b16tob8((b16_t)arg) >> 1); break; default: sninfo("Unrecognized cmd: %d\n", cmd); ret = -ENOTTY; break; } return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: adt7320_register * * Description: * Register the ADT7320 character device as 'devpath' * * Input Parameters: * devpath - The full path to the driver to register. E.g., "/dev/temp0" * spi - An instance of the SPI bus to use to communicate with ADT7320 * spidev - The SPI device number used to select the correct CS line * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int adt7320_register(FAR const char *devpath, FAR struct spi_dev_s *spi, int spidev) { FAR struct adt7320_dev_s *priv; int ret; /* Sanity check */ DEBUGASSERT(spi != NULL); /* Initialize the ADT7320 device structure */ priv = kmm_malloc(sizeof(struct adt7320_dev_s)); if (priv == NULL) { snerr("ERROR: Failed to allocate instance\n"); return -ENOMEM; } priv->spi = spi; priv->spidev = spidev; priv->fahrenheit = false; /* Register the character driver */ ret = register_driver(devpath, &g_adt7320fops, 0666, priv); if (ret < 0) { snerr("ERROR: Failed to register driver: %d\n", ret); kmm_free(priv); } /* Reset the ADT7320 SPI interface */ adt7320_reset(priv); return ret; } #endif /* CONFIG_SPI && CONFIG_SENSORS_ADT7320 */