drivers/at30tse75x: add device driver for AT30TSE75x temperature sensor

Makefile.dep

@@ -425,6 +425,10 @@ ifneq (,$(filter ltc4150,$(USEMODULE)))
     USEMODULE += xtimer
 endif
 
+ifneq (,$(filter at30tse75x,$(USEMODULE)))
+  USEMODULE += xtimer
+endif
+
 ifneq (,$(filter pthread,$(USEMODULE)))
     USEMODULE += xtimer
     USEMODULE += vtimer

drivers/at30tse75x/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

drivers/at30tse75x/at30tse75x.c

@@ -0,0 +1,317 @@
+/*
+ * Copyright (C) Daniel Krebs
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @file
+ * @brief       Driver for the AT30TSE75x temperature sensor with serial EEPROM
+ *
+ * @author      Daniel Krebs <github@daniel-krebs.net>
+ */
+
+
+#include "periph/i2c.h"
+#include "xtimer.h"
+
+#include "at30tse75x.h"
+
+#define ENABLE_DEBUG (0)
+#include "debug.h"
+
+static inline float temperature_to_float(uint16_t temp)
+{
+    /* Integer part is 8-bit signed */
+    int8_t temp_int = (temp & AT30TSE75X_INTEGER_MASK) >>
+                        AT30TSE75X_INTEGER_SHIFT;
+    /* Fractional part is multiple of 0.0625 */
+    uint8_t frac_multiplier = (temp & AT30TSE75X_FRACTIONAL_MASK) >>
+                        AT30TSE75X_FRACTIONAL_SHIFT;
+
+    return temp_int + (frac_multiplier * AT30TSE75X_FRACTIONAL_BASE);
+}
+
+static int at30tse75x_get_register(at30tse75x_t* dev, uint8_t reg, uint16_t* data)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_read_regs(dev->i2c, dev->addr, reg, (char*) data, 2) <= 0) {
+        DEBUG("[at30tse75x] Can't read register 0x%x\n", reg);
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+
+    return 0;
+}
+
+static int at30tse75x_set_register(at30tse75x_t* dev, uint8_t reg, uint16_t* data)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_write_regs(dev->i2c, dev->addr, reg, (char*) data, 2) <= 0) {
+        DEBUG("[at30tse75x] Can't write to register 0x%x\n", reg);
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+
+    return 0;
+}
+
+static int at30tse75x_reset(at30tse75x_t* dev)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_write_byte(dev->i2c, 0x00, AT30TSE75X_CMD__GENERAL_CALL_RESET) != 1) {
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+    /* Wait for reset to complete */
+    xtimer_usleep(500);
+    return 0;
+}
+
+int at30tse75x_get_config(at30tse75x_t* dev, uint8_t* data)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_read_reg(dev->i2c, dev->addr, AT30TSE75X_REG__CONFIG, (char*) data) <= 0) {
+        DEBUG("[at30tse75x] Can't read CONFIG register\n");
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+
+    return 0;
+}
+
+int at30tse75x_set_config(at30tse75x_t* dev, uint8_t data)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_write_reg(dev->i2c, dev->addr, AT30TSE75X_REG__CONFIG, (char) data) <= 0) {
+        DEBUG("[at30tse75x] Can't write to CONFIG register\n");
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+
+    return 0;
+}
+
+int at30tse75x_set_resolution(at30tse75x_t* dev, at30tse75x_resolution_t resolution)
+{
+    uint8_t config;
+
+    if(resolution < AT30TSE75X_RESOLUTION_9BIT ||
+       resolution > AT30TSE75X_RESOLUTION_12BIT) {
+        return -2;
+    }
+
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    config &= ~(AT30TSE75X_CONFIG__RESOLUTION_MASK);
+    config |= resolution << AT30TSE75X_CONFIG__RESOLUTION_SHIFT;
+
+    if(at30tse75x_set_config(dev, config) != 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int at30tse75x_set_mode(at30tse75x_t* dev, at30tse75x_mode_t mode)
+{
+    uint8_t config;
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    switch(mode) {
+    case AT30TSE75X_MODE_ONE_SHOT:
+        config |= AT30TSE75X_CONFIG__SHUTDOWN_BIT;
+        /* Don't touch alarm mode */
+        break;
+    case AT30TSE75X_MODE_COMPARATOR:
+        config &= ~(AT30TSE75X_CONFIG__SHUTDOWN_BIT);
+        config &= ~(AT30TSE75X_CONFIG__ALARM_MODE_BIT);
+        break;
+    case AT30TSE75X_MODE_INTERRUPT:
+        config &= ~(AT30TSE75X_CONFIG__SHUTDOWN_BIT);
+        config |= AT30TSE75X_CONFIG__ALARM_MODE_BIT;
+        break;
+    default:
+        return -2;
+    }
+
+    if(at30tse75x_set_config(dev, config) != 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int at30tse75x_set_alarm_polarity(at30tse75x_t* dev, at30tse75x_alarm_polatity_t polarity)
+{
+    uint8_t config;
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    switch(polarity) {
+    case AT30TSE75X_ALARM_ACTIVE_HIGH:
+        config |= AT30TSE75X_CONFIG__ALERT_POL_BIT;
+        break;
+    case AT30TSE75X_ALARM_ACTIVE_LOW:
+        config &= ~(AT30TSE75X_CONFIG__ALERT_POL_BIT);
+        break;
+    default:
+        return -2;
+    }
+
+    if(at30tse75x_set_config(dev, config) != 0) {
+            return -1;
+        }
+
+    return 0;
+}
+
+int at30tse75x_set_fault_tolerance(at30tse75x_t* dev, at30tse75x_fault_tolerance_t tolerance)
+{
+    if(tolerance < AT30TSE75X_ALARM_AFTER_1 ||
+       tolerance > AT30TSE75X_ALARM_AFTER_6) {
+        return -2;
+    }
+
+    uint8_t config;
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    config &= ~(AT30TSE75X_CONFIG__FTQ_MASK);
+    config |= tolerance << AT30TSE75X_CONFIG__FTQ_SHIFT;
+
+    if(at30tse75x_set_config(dev, config) != 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int at30tse75x_set_limit_low(at30tse75x_t* dev, int8_t t_low)
+{
+    uint16_t tmp = (t_low << 8) | (0x00);
+    return at30tse75x_set_register(dev, AT30TSE75X_REG__LIMIT_LOW, &tmp);
+}
+
+int at30tse75x_set_limit_high(at30tse75x_t* dev, int8_t t_high)
+{
+    uint16_t tmp = (t_high << 8) | (0x00);
+    return at30tse75x_set_register(dev, AT30TSE75X_REG__LIMIT_HIGH, &tmp);
+}
+
+int at30tse75x_save_config(at30tse75x_t* dev)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_write_byte(dev->i2c, dev->addr, AT30TSE75X_CMD__SAVE_TO_NVRAM) != 1) {
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+    /* Wait for copy to complete */
+    xtimer_usleep(5000);
+    return 0;
+}
+
+int at30tse75x_restore_config(at30tse75x_t* dev)
+{
+    i2c_acquire(dev->i2c);
+    xtimer_spin(AT30TSE75X_BUS_FREE_TIME_US);
+    if(i2c_write_byte(dev->i2c, dev->addr, AT30TSE75X_CMD__RESTORE_FROM_NVRAM) != 1) {
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+    /* Wait for copy to complete */
+    xtimer_usleep(200);
+    return 0;
+}
+
+int at30tse75x_get_temperature(at30tse75x_t* dev, float* temperature)
+{
+    uint16_t tmp;
+    uint8_t config;
+
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    /* If sensor is shutdown trigger One-Shot mode*/
+    if(config & AT30TSE75X_CONFIG__SHUTDOWN_BIT) {
+
+        config |= AT30TSE75X_CONFIG__OS_BIT;
+        if(at30tse75x_set_config(dev, config) != 0) {
+            return -1;
+        }
+
+        /* Use resolution to calculate conversion time */
+         uint8_t resolution = (config & AT30TSE75X_CONFIG__RESOLUTION_MASK) >>
+                                   AT30TSE75X_CONFIG__RESOLUTION_SHIFT;
+
+        /* Wait until conversion is finished */
+        xtimer_usleep((uint32_t)(25000 << resolution));
+    }
+
+    /* Read temperature */
+    if(at30tse75x_get_register(dev, AT30TSE75X_REG__TEMPERATURE, &tmp) != 0) {
+        return -1;
+    }
+
+    /* Convert fixed point to float */
+    *temperature = temperature_to_float(tmp);
+
+    return 0;
+}
+
+int at30tse75x_init(at30tse75x_t* dev, i2c_t i2c, i2c_speed_t speed, uint8_t addr)
+{
+    uint8_t config;
+
+    dev->i2c = i2c;
+
+    if( (addr < 0x48) || (addr > 0x4f) ) {
+        DEBUG("[at30tse75x] Invalid address\n");
+        return -2;
+    }
+    dev->addr = addr;
+
+    i2c_acquire(dev->i2c);
+    if(i2c_init_master(dev->i2c, speed) != 0) {
+        DEBUG("[at30tse75x] Can't initialize I2C master\n");
+        i2c_release(dev->i2c);
+        return -1;
+    }
+    i2c_release(dev->i2c);
+
+    /* Reset the device */
+    if(at30tse75x_reset(dev) != 0) {
+        return -1;
+    }
+
+    /* Poll the device, fail if unavailable */
+    if(at30tse75x_get_config(dev, &config) != 0) {
+        return -1;
+    }
+
+    DEBUG("[at30tse75x] Config: 0x%x\n", config);
+
+    return 0;
+}