/**************************************************************************** * drivers/sensors/lps25h.c * * Copyright (C) 2014-2017 Haltian Ltd. All rights reserved. * * 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 #include #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-Processor Definitions ****************************************************************************/ #ifdef CONFIG_DEBUG_LPS25H # define lps25h_dbg(x, ...) _info(x, ##__VA_ARGS__) #else # define lps25h_dbg(x, ...) sninfo(x, ##__VA_ARGS__) #endif #ifndef CONFIG_LPS25H_I2C_FREQUENCY # define CONFIG_LPS25H_I2C_FREQUENCY 400000 #endif #define LPS25H_PRESSURE_INTERNAL_DIVIDER 4096 /* 'AN4450 - Hardware and software guidelines for use of LPS25H pressure * sensors' - '6.2 One-shot mode conversion time estimation' gives estimates * for conversion times: * * Typical conversion time ≈ 62*(Pavg+Tavg) + 975 μs * ex: Tavg = 64; Pavg = 512; Typ. conversation time ≈ 36.7 ms (compatible with * ODT=25 Hz) * ex: Tavg = 32; Pavg = 128; Typ. conversation time ≈ 10.9 ms * The formula is accurate within +/- 3% at room temperature * * Set timeout to 2 * max.conversation time (2*36.7*1.03 = 76 ms). */ #define LPS25H_RETRY_TIMEOUT_MSECS 76 #define LPS25H_MAX_RETRIES 5 #define LPS25H_I2C_RETRIES 10 /* Registers */ #define LPS25H_REF_P_XL 0x08 #define LPS25H_REF_P_L 0x09 #define LPS25H_REF_P_H 0x0a #define LPS25H_WHO_AM_I 0x0f #define LPS25H_RES_CONF 0x10 #define LPS25H_CTRL_REG1 0x20 #define LPS25H_CTRL_REG2 0x21 #define LPS25H_CTRL_REG3 0x22 #define LPS25H_CTRL_REG4 0x23 #define LPS25H_INT_CFG 0x24 #define LPS25H_INT_SOURCE 0x25 #define LPS25H_STATUS_REG 0x27 #define LPS25H_PRESS_POUT_XL 0x28 #define LPS25H_PRESS_OUT_L 0x29 #define LPS25H_PRESS_OUT_H 0x2a #define LPS25H_TEMP_OUT_L 0x2b #define LPS25H_TEMP_OUT_H 0x2c #define LPS25H_FIFO_CTRL 0x2e #define LPS25H_FIFO_STATUS 0x2f #define LPS25H_THS_P_L 0x30 #define LPS25H_THS_P_H 0x31 #define LPS25H_RPDS_L 0x39 #define LPS25H_RPDS_H 0x3a /* Bits in registers */ #define LPS25H_AUTO_ZERO (1 << 2) #define LPS25H_BDU (1 << 2) #define LPS25H_DIFF_EN (1 << 3) #define LPS25H_FIFO_EN (1 << 6) #define LPS25H_WTM_EN (1 << 5) #define LPS25H_FIFO_MEAN_DEC (1 << 4) #define LPS25H_PD (1 << 7) #define LPS25H_ONE_SHOT (1 << 0) #define LPS25H_INT_H_L (1 << 7) #define LPS25H_PP_OD (1 << 6) /**************************************************************************** * Private Types ****************************************************************************/ struct lps25h_dev_s { struct i2c_master_s *i2c; uint8_t addr; bool irqenabled; volatile bool int_pending; sem_t devsem; sem_t waitsem; lps25h_config_t *config; }; enum LPS25H_RES_CONF_AVG_PRES { PRES_AVG_8 = 0, PRES_AVG_32, PRES_AVG_128, PRES_AVG_512 }; enum LPS25H_RES_CONF_AVG_TEMP { TEMP_AVG_8 = 0, TEMP_AVG_16, TEMP_AVG_32, TEMP_AVG_64 }; enum LPS25H_CTRL_REG1_ODR { CTRL_REG1_ODR_ONE_SHOT = 0, CTRL_REG1_ODR_1Hz, CTRL_REG1_ODR_7Hz, CTRL_REG1_ODR_12_5Hz, CTRL_REG1_ODR_25Hz }; enum LPS25H_CTRL_REG4_P1 { P1_DRDY = 0x1, P1_OVERRUN = 0x02, P1_WTM = 0x04, P1_EMPTY = 0x08 }; enum LPS25H_FIFO_CTRL_MODE { BYPASS_MODE = 0x0, FIFO_STOP_WHEN_FULL, STREAM_NEWEST_IN_FIFO, STREAM_DEASSERTED, BYPASS_DEASSERTED_STREAM, FIFO_MEAN = 0x06, BYPASS_DEASSERTED_FIFO }; enum LPS25H_FIFO_CTRL_WTM { SAMPLE_2 = 0x01, SAMPLE_4 = 0x03, SAMPLE_8 = 0x07, SAMPLE_16 = 0x0f, SAMPLE_32 = 0x1f }; enum LPS25H_INT_CFG_OP { PH_E = 0x1, PL_E = 0x2, LIR = 0x4 }; /************************************************************************************ * Private Function Prototypes ************************************************************************************/ static int lps25h_open(FAR struct file *filep); static int lps25h_close(FAR struct file *filep); static ssize_t lps25h_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static ssize_t lps25h_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); static int lps25h_ioctl(FAR struct file *filep, int cmd, unsigned long arg); static int lps25h_configure_dev(FAR struct lps25h_dev_s *dev); static int lps25h_read_pressure(FAR struct lps25h_dev_s *dev, FAR lps25h_pressure_data_t *pres); static int lps25h_read_temper(FAR struct lps25h_dev_s *dev, FAR lps25h_temper_data_t *temper); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations g_lps25hops = { lps25h_open, /* open */ lps25h_close, /* close */ lps25h_read, /* read */ lps25h_write, /* write */ NULL, /* seek */ lps25h_ioctl /* ioctl */ #ifndef CONFIG_DISABLE_POLL , NULL /* poll */ #endif #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS , NULL /* unlink */ #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ static int lps25h_do_transfer(FAR struct lps25h_dev_s *dev, FAR struct i2c_msg_s *msgv, size_t nmsg) { int ret = -EIO; int retries; for (retries = 0; retries < LPS25H_I2C_RETRIES; retries++) { ret = I2C_TRANSFER(dev->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 == LPS25H_I2C_RETRIES - 1) { break; } ret = I2C_RESET(dev->i2c); if (ret < 0) { lps25h_dbg("I2C_RESET failed: %d\n", ret); return ret; } #endif } } lps25h_dbg("xfer failed: %d\n", ret); return ret; } static int lps25h_write_reg8(struct lps25h_dev_s *dev, uint8_t reg_addr, const uint8_t value) { struct i2c_msg_s msgv[2] = { { .frequency = CONFIG_LPS25H_I2C_FREQUENCY, .addr = dev->addr, .flags = 0, .buffer = ®_addr, .length = 1 }, { .frequency = CONFIG_LPS25H_I2C_FREQUENCY, .addr = dev->addr, .flags = I2C_M_NOSTART, .buffer = (void *)&value, .length = 1 } }; return lps25h_do_transfer(dev, msgv, 2); } static int lps25h_read_reg8(FAR struct lps25h_dev_s *dev, FAR uint8_t *reg_addr, FAR uint8_t *value) { struct i2c_msg_s msgv[2] = { { .frequency = CONFIG_LPS25H_I2C_FREQUENCY, .addr = dev->addr, .flags = 0, .buffer = reg_addr, .length = 1 }, { .frequency = CONFIG_LPS25H_I2C_FREQUENCY, .addr = dev->addr, .flags = I2C_M_READ, .buffer = value, .length = 1 } }; return lps25h_do_transfer(dev, msgv, 2); } static int lps25h_power_on_off(FAR struct lps25h_dev_s *dev, bool on) { int ret; uint8_t value; value = on ? LPS25H_PD : 0; ret = lps25h_write_reg8(dev, LPS25H_CTRL_REG1, value); return ret; } static int lps25h_open(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct lps25h_dev_s *dev = inode->i_private; uint8_t value = 0; uint8_t addr = LPS25H_WHO_AM_I; int32_t ret; /* Get exclusive access */ do { ret = nxsem_wait(&dev->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); dev->config->set_power(dev->config, true); ret = lps25h_read_reg8(dev, &addr, &value); if (ret < 0) { lps25h_dbg("Cannot read device's ID\n"); dev->config->set_power(dev->config, false); goto out; } lps25h_dbg("WHO_AM_I: 0x%2x\n", value); dev->config->irq_enable(dev->config, true); dev->irqenabled = true; out: nxsem_post(&dev->devsem); return ret; } static int lps25h_close(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct lps25h_dev_s *dev = inode->i_private; int ret; /* Get exclusive access */ do { ret = nxsem_wait(&dev->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); dev->config->irq_enable(dev->config, false); dev->irqenabled = false; ret = lps25h_power_on_off(dev, false); dev->config->set_power(dev->config, false); lps25h_dbg("CLOSED\n"); nxsem_post(&dev->devsem); return ret; } static ssize_t lps25h_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { FAR struct inode *inode = filep->f_inode; FAR struct lps25h_dev_s *dev = inode->i_private; lps25h_pressure_data_t data; ssize_t length = 0; int ret; /* Get exclusive access */ do { ret = nxsem_wait(&dev->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); ret = lps25h_configure_dev(dev); if (ret < 0) { lps25h_dbg("cannot configure sensor: %d\n", ret); goto out; } ret = lps25h_read_pressure(dev, &data); if (ret < 0) { lps25h_dbg("cannot read data: %d\n", ret); } else { /* This interface is mainly intended for easy debugging in nsh. */ length = snprintf(buffer, buflen, "%u\n", data.pressure_Pa); if (length > buflen) { length = buflen; } } out: nxsem_post(&dev->devsem); return length; } static ssize_t lps25h_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { ssize_t length = 0; return length; } static void lps25h_notify(FAR struct lps25h_dev_s *dev) { DEBUGASSERT(dev != NULL); dev->int_pending = true; nxsem_post(&dev->waitsem); } static int lps25h_int_handler(int irq, FAR void *context, FAR void *arg) { FAR struct lps25h_dev_s *dev = (FAR struct lps25h_dev_s *)arg; DEBUGASSERT(dev != NULL); lps25h_notify(dev); lps25h_dbg("lps25h interrupt\n"); return OK; } static int lps25h_configure_dev(FAR struct lps25h_dev_s *dev) { int ret = 0; ret = lps25h_power_on_off(dev, false); if (ret < 0) { return ret; } /* Enable FIFO */ ret = lps25h_write_reg8(dev, LPS25H_CTRL_REG2, LPS25H_FIFO_EN); if (ret < 0) { return ret; } ret = lps25h_write_reg8(dev, LPS25H_FIFO_CTRL, (BYPASS_MODE << 5)); if (ret < 0) { return ret; } ret = lps25h_write_reg8(dev, LPS25H_CTRL_REG4, P1_DRDY); if (ret < 0) { return ret; } /* Write CTRL_REG1 to turn device on */ ret = lps25h_write_reg8(dev, LPS25H_CTRL_REG1, LPS25H_PD | (CTRL_REG1_ODR_1Hz << 4)); return ret; } static int lps25h_one_shot(FAR struct lps25h_dev_s *dev) { int ret = ERROR; int retries; struct timespec abstime; irqstate_t flags; if (!dev->irqenabled) { lps25h_dbg("IRQ disabled!\n"); } /* Retry one-shot measurement multiple times. */ for (retries = 0; retries < LPS25H_MAX_RETRIES; retries++) { /* Power off so we start from a known state. */ ret = lps25h_power_on_off(dev, false); if (ret < 0) { return ret; } /* Initiate a one shot mode measurement */ ret = lps25h_write_reg8(dev, LPS25H_CTRL_REG2, LPS25H_ONE_SHOT); if (ret < 0) { return ret; } /* Power on to start measurement. */ ret = lps25h_power_on_off(dev, true); if (ret < 0) { return ret; } (void)clock_gettime(CLOCK_REALTIME, &abstime); abstime.tv_sec += (LPS25H_RETRY_TIMEOUT_MSECS / 1000); abstime.tv_nsec += (LPS25H_RETRY_TIMEOUT_MSECS % 1000) * 1000 * 1000; while (abstime.tv_nsec >= (1000 * 1000 * 1000)) { abstime.tv_sec++; abstime.tv_nsec -= 1000 * 1000 * 1000; } while ((ret = nxsem_timedwait(&dev->waitsem, &abstime)) < 0) { if (ret == -EINTR) { continue; } else if (ret == -ETIMEDOUT) { uint8_t reg = LPS25H_CTRL_REG2; uint8_t value; /* In 'AN4450 - Hardware and software guidelines for use of * LPS25H pressure sensors' - '4.3 One-shot mode measurement * sequence', one-shot mode example is given where interrupt line * is not used, but CTRL_REG2 is polled until ONE_SHOT bit is * unset (as it is self-clearing). Check ONE_SHOT bit status here * to see if we just missed interrupt. */ ret = lps25h_read_reg8(dev, ®, &value); if (ret < 0) { break; } if ((value & LPS25H_ONE_SHOT) == 0) { /* One-shot completed. */ ret = OK; break; } } else { /* Some unknown mystery error */ DEBUGASSERT(false); return ret; } } if (ret == OK) { break; } lps25h_dbg("Retrying one-shot measurement: retries=%d\n", retries); } if (ret != OK) { return -ETIMEDOUT; } flags = enter_critical_section(); dev->int_pending = false; leave_critical_section(flags); return ret; } static int lps25h_read_pressure(FAR struct lps25h_dev_s *dev, FAR lps25h_pressure_data_t *pres) { int ret; uint8_t pres_addr_h = LPS25H_PRESS_OUT_H; uint8_t pres_addr_l = LPS25H_PRESS_OUT_L; uint8_t pres_addr_xl = LPS25H_PRESS_POUT_XL; uint8_t pres_value_h = 0; uint8_t pres_value_l = 0; uint8_t pres_value_xl = 0; int32_t pres_res = 0; ret = lps25h_one_shot(dev); if (ret < 0) { return ret; } ret = lps25h_read_reg8(dev, &pres_addr_h, &pres_value_h); if (ret < 0) { return ret; } ret = lps25h_read_reg8(dev, &pres_addr_l, &pres_value_l); if (ret < 0) { return ret; } ret = lps25h_read_reg8(dev, &pres_addr_xl, &pres_value_xl); if (ret < 0) { return ret; } pres_res = ((int32_t) pres_value_h << 16) | ((int16_t) pres_value_l << 8) | pres_value_xl; /* Add to entropy pool. */ add_sensor_randomness(pres_res); /* Convert to more usable format. */ pres->pressure_int_hP = pres_res / LPS25H_PRESSURE_INTERNAL_DIVIDER; pres->pressure_Pa = (uint64_t)pres_res * 100000 / LPS25H_PRESSURE_INTERNAL_DIVIDER; pres->raw_data = pres_res; lps25h_dbg("Pressure: %u Pa\n", pres->pressure_Pa); return ret; } static int lps25h_read_temper(FAR struct lps25h_dev_s *dev, FAR lps25h_temper_data_t *temper) { int ret; uint8_t temper_addr_h = LPS25H_TEMP_OUT_H; uint8_t temper_addr_l = LPS25H_TEMP_OUT_L; uint8_t temper_value_h = 0; uint8_t temper_value_l = 0; int32_t temper_res; int16_t raw_data; ret = lps25h_read_reg8(dev, &temper_addr_h, &temper_value_h); if (ret < 0) { return ret; } ret = lps25h_read_reg8(dev, &temper_addr_l, &temper_value_l); if (ret < 0) { return ret; } raw_data = (temper_value_h << 8) | temper_value_l; /* Add to entropy pool. */ add_sensor_randomness(raw_data); /* T(⁰C) = 42.5 + (raw / 480) * => * T(⁰C) * scale = (425 * 48 + raw) * scale / 480; */ temper_res = (425 * 48 + raw_data); temper_res *= LPS25H_TEMPER_DIVIDER; temper_res /= 480; temper->int_temper = temper_res; temper->raw_data = raw_data; lps25h_dbg("Temperature: %d\n", temper_res); return ret; } static int lps25h_who_am_i(struct lps25h_dev_s *dev, lps25h_who_am_i_data * who_am_i_data) { uint8_t who_addr = LPS25H_WHO_AM_I; return lps25h_read_reg8(dev, &who_addr, &who_am_i_data->who_am_i); } static int lps25h_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct lps25h_dev_s *dev = inode->i_private; int ret; /* Get exclusive access */ do { ret = nxsem_wait(&dev->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); switch (cmd) { case SNIOC_CFGR: ret = lps25h_configure_dev(dev); break; case SNIOC_PRESSURE_OUT: ret = lps25h_read_pressure(dev, (lps25h_pressure_data_t *) arg); break; case SNIOC_TEMPERATURE_OUT: /* NOTE: call SNIOC_PRESSURE_OUT before this one, * or results are bogus. */ ret = lps25h_read_temper(dev, (lps25h_temper_data_t *) arg); break; case SNIOC_SENSOR_OFF: ret = lps25h_power_on_off(dev, false); break; case SNIOC_GET_DEV_ID: ret = lps25h_who_am_i(dev, (lps25h_who_am_i_data *) arg); break; default: ret = -ENOTTY; break; } nxsem_post(&dev->devsem); return ret; } int lps25h_register(FAR const char *devpath, FAR struct i2c_master_s *i2c, uint8_t addr, FAR lps25h_config_t *config) { int ret = 0; FAR struct lps25h_dev_s *dev; dev = (struct lps25h_dev_s *)kmm_zalloc(sizeof(struct lps25h_dev_s)); if (!dev) { lps25h_dbg("Memory cannot be allocated for LPS25H sensor\n"); return -ENOMEM; } nxsem_init(&dev->devsem, 0, 1); nxsem_init(&dev->waitsem, 0, 0); dev->addr = addr; dev->i2c = i2c; dev->config = config; if (dev->config->irq_clear) { dev->config->irq_clear(dev->config); } ret = register_driver(devpath, &g_lps25hops, 0666, dev); lps25h_dbg("Registered with %d\n", ret); if (ret < 0) { kmm_free(dev); lps25h_dbg("Error occurred during the driver registering\n"); return ERROR; } dev->config->irq_attach(config, lps25h_int_handler, dev); dev->config->irq_enable(config, false); dev->irqenabled = false; return OK; }