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drivers: sensor: add driver for the LM77 temperature sensor

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Add sensor driver for the LM77 temperature sensor.

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>
This commit is contained in:
Henrik Brix Andersen 2021-07-14 14:23:59 +02:00 • committed by Christopher Friedt
commit eb616130d7
5 changed files with 473 additions and 0 deletions
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1
drivers/sensor/CMakeLists.txt
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@ -46,6 +46,7 @@ add_subdirectory_ifdef(CONFIG_LIS2DW12 lis2dw12)
add_subdirectory_ifdef(CONFIG_LIS2MDL lis2mdl)
add_subdirectory_ifdef(CONFIG_LIS3MDL lis3mdl)
add_subdirectory_ifdef(CONFIG_LM75 lm75)
add_subdirectory_ifdef(CONFIG_LM77 lm77)
add_subdirectory_ifdef(CONFIG_LPS22HB lps22hb)
add_subdirectory_ifdef(CONFIG_LPS22HH lps22hh)
add_subdirectory_ifdef(CONFIG_LPS25HB lps25hb)

2
drivers/sensor/Kconfig
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@ -130,6 +130,8 @@ source "drivers/sensor/lis3mdl/Kconfig"
source "drivers/sensor/lm75/Kconfig"
source "drivers/sensor/lm77/Kconfig"
source "drivers/sensor/lps22hb/Kconfig"
source "drivers/sensor/lps22hh/Kconfig"

5
drivers/sensor/lm77/CMakeLists.txt Normal file
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@ -0,0 +1,5 @@
# Copyright (c) 2021 Vestas Wind Systems A/S
# SPDX-License-Identifier: Apache-2.0
zephyr_library()
zephyr_library_sources(lm77.c)

39
drivers/sensor/lm77/Kconfig Normal file
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@ -0,0 +1,39 @@
# LM77 temperature sensor configuration
#
# Copyright (c) 2021 Vestas Wind Systems A/S
# SPDX-License-Identifier: Apache-2.0
menuconfig LM77
bool "LM77 Temperature Sensor"
default $(dt_compat_enabled,lm77)
depends on I2C
help
Enable driver for the LM77 digital temperature sensor with 2-wire
interface.
config LM77_TRIGGER
bool "Trigger support"
depends on LM77
default y
help
Enable trigger support for the LM77 digital temperature sensor.
Trigger events are based on the LM77 INT signal (configured for event
interrupt mode). After a trigger event the LM77 temperature must be
read in order to reset and rearm the trigger.
if LM77_TRIGGER
config LM77_TRIGGER_THREAD_STACK_SIZE
int "Stack size for the trigger workqueue thread"
default 512
help
Size of the stack used for the internal trigger workqueue thread.
config LM77_TRIGGER_THREAD_PRIO
int "Priority for the trigger workqueue thread"
default 0
help
Priority level for the internal trigger workqueue thread.
endif # LM77_TRIGGER

426
drivers/sensor/lm77/lm77.c Normal file
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@ -0,0 +1,426 @@
/*
* Copyright (c) 2021 Vestas Wind Systems A/S
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT lm77
#include <device.h>
#include <drivers/gpio.h>
#include <drivers/i2c.h>
#include <drivers/sensor.h>
#include <logging/log.h>
#include <sys/byteorder.h>
LOG_MODULE_REGISTER(lm77, CONFIG_SENSOR_LOG_LEVEL);
/*
* Only compile in trigger support if enabled in Kconfig and at least one
* enabled lm77 devicetree node has the int-gpios property.
*/
#define LM77_TRIGGER_SUPPORT_INST(inst) DT_INST_NODE_HAS_PROP(inst, int_gpios) ||
#define LM77_TRIGGER_SUPPORT \
(CONFIG_LM77_TRIGGER && (DT_INST_FOREACH_STATUS_OKAY(LM77_TRIGGER_SUPPORT_INST) 0))
/* LM77 registers */
#define LM77_REG_TEMP 0x00U
#define LM77_REG_CONFIG 0x01U
#define LM77_REG_THYST 0x02U
#define LM77_REG_TCRIT 0x03U
#define LM77_REG_TLOW 0x04U
#define LM77_REG_THIGH 0x05U
/* LM77 configuration register bits */
union lm77_reg_config {
uint8_t reg;
struct {
uint8_t shutdown : 1;
uint8_t int_mode : 1;
uint8_t tcrita_pol : 1;
uint8_t int_pol : 1;
uint8_t fault_queue : 1;
uint8_t reserved : 3;
} __packed;
};
struct lm77_config {
struct i2c_dt_spec i2c;
union lm77_reg_config config_dt;
#if LM77_TRIGGER_SUPPORT
struct gpio_dt_spec int_gpio;
#endif /* LM77_TRIGGER_SUPPORT */
};
struct lm77_data {
int16_t temp;
#if LM77_TRIGGER_SUPPORT
const struct device *dev;
struct k_work_q workq;
struct k_work work;
struct gpio_callback int_gpio_cb;
const struct sensor_trigger *trigger;
sensor_trigger_handler_t trigger_handler;
K_KERNEL_STACK_MEMBER(stack, CONFIG_LM77_TRIGGER_THREAD_STACK_SIZE);
#endif /* LM77_TRIGGER_SUPPORT */
};
static int lm77_write_config(const struct device *dev, uint8_t value)
{
const struct lm77_config *config = dev->config;
uint8_t buf[2] = { LM77_REG_CONFIG, value };
return i2c_write_dt(&config->i2c, buf, sizeof(buf));
}
static int lm77_read_temp(const struct device *dev, uint8_t reg, int16_t *value)
{
const struct lm77_config *config = dev->config;
uint8_t buf[2];
int err;
err = i2c_write_read_dt(&config->i2c, &reg, sizeof(reg), &buf, sizeof(buf));
if (err < 0) {
LOG_ERR("failed to read temperature register 0x%02x (err %d)", reg, err);
return err;
}
*value = sys_get_be16(buf);
return 0;
}
static int lm77_write_temp(const struct device *dev, uint8_t reg, int16_t value)
{
const struct lm77_config *config = dev->config;
uint8_t buf[3] = { reg, value >> 8, value };
return i2c_write_dt(&config->i2c, buf, sizeof(buf));
}
static void lm77_sensor_value_to_temp(const struct sensor_value *val, int16_t *temp)
{
/* Integer part in degrees Celsius (LSB = 0.5 degrees Celsius) */
*temp = val->val1 << 1;
/* Fractional part in micro degrees Celsius */
*temp += (val->val2 * 2) / 1000000;
/* Shift up to include "status" bits */
*temp <<= 3;
}
static void lm77_temp_to_sensor_value(int16_t temp, struct sensor_value *val)
{
/* Shift down to remove "status" bits (LSB = 0.5 degrees Celsius) */
temp = (temp >> 3) * 5;
/* Integer part in degrees Celsius */
val->val1 = temp / 10;
/* Fractional part in micro degrees Celsius */
val->val2 = temp % 10;
val->val2 *= 100000;
}
static int lm77_attr_set(const struct device *dev, enum sensor_channel chan,
enum sensor_attribute attr, const struct sensor_value *val)
{
int16_t temp = 0;
uint8_t reg;
int err;
__ASSERT_NO_MSG(val != NULL);
if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
switch (attr) {
case SENSOR_ATTR_LOWER_THRESH:
reg = LM77_REG_TLOW;
break;
case SENSOR_ATTR_UPPER_THRESH:
reg = LM77_REG_THIGH;
break;
case SENSOR_ATTR_ALERT:
reg = LM77_REG_TCRIT;
break;
case SENSOR_ATTR_HYSTERESIS:
reg = LM77_REG_THYST;
break;
default:
return -ENOTSUP;
}
lm77_sensor_value_to_temp(val, &temp);
err = lm77_write_temp(dev, reg, temp);
if (err < 0) {
LOG_ERR("failed to write register 0x%02x (err %d)", reg, err);
return err;
}
return 0;
}
static int lm77_attr_get(const struct device *dev, enum sensor_channel chan,
enum sensor_attribute attr, struct sensor_value *val)
{
int16_t temp;
uint8_t reg;
int err;
__ASSERT_NO_MSG(val != NULL);
if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
switch (attr) {
case SENSOR_ATTR_LOWER_THRESH:
reg = LM77_REG_TLOW;
break;
case SENSOR_ATTR_UPPER_THRESH:
reg = LM77_REG_THIGH;
break;
case SENSOR_ATTR_ALERT:
reg = LM77_REG_TCRIT;
break;
case SENSOR_ATTR_HYSTERESIS:
reg = LM77_REG_THYST;
break;
default:
return -ENOTSUP;
}
err = lm77_read_temp(dev, reg, &temp);
if (err < 0) {
LOG_ERR("failed to read register 0x%02x (err %d)", reg, err);
return err;
}
lm77_temp_to_sensor_value(temp, val);
return 0;
}
#if LM77_TRIGGER_SUPPORT
static int lm77_trigger_set(const struct device *dev, const struct sensor_trigger *trig,
sensor_trigger_handler_t handler)
{
const struct lm77_config *config = dev->config;
struct lm77_data *data = dev->data;
gpio_flags_t flags;
int err;
__ASSERT_NO_MSG(trig != NULL);
if (trig->type != SENSOR_TRIG_THRESHOLD || trig->chan != SENSOR_CHAN_AMBIENT_TEMP ||
config->int_gpio.port == NULL) {
return -ENOTSUP;
}
if (handler != NULL) {
flags = GPIO_INT_EDGE_TO_ACTIVE;
} else {
flags = GPIO_INT_DISABLE;
}
err = gpio_pin_interrupt_configure_dt(&config->int_gpio, flags);
if (err < 0) {
LOG_ERR("failed to configure INT GPIO IRQ (err %d)", err);
return err;
}
data->trigger = trig;
data->trigger_handler = handler;
return 0;
}
static void lm77_trigger_work_handler(struct k_work *item)
{
struct lm77_data *data = CONTAINER_OF(item, struct lm77_data, work);
sensor_trigger_handler_t handler = data->trigger_handler;
if (handler != NULL) {
handler(data->dev, (struct sensor_trigger *)data->trigger);
}
}
static void lm77_int_gpio_callback_handler(const struct device *port,
struct gpio_callback *cb,
gpio_port_pins_t pins)
{
struct lm77_data *data = CONTAINER_OF(cb, struct lm77_data, int_gpio_cb);
ARG_UNUSED(port);
ARG_UNUSED(pins);
k_work_submit_to_queue(&data->workq, &data->work);
}
#endif /* LM77_TRIGGER_SUPPORT */
static int lm77_sample_fetch(const struct device *dev, enum sensor_channel chan)
{
struct lm77_data *data = dev->data;
int16_t temp;
int err;
if (chan != SENSOR_CHAN_ALL && chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
err = lm77_read_temp(dev, LM77_REG_TEMP, &temp);
if (err < 0) {
LOG_ERR("failed to read temperature (err %d)", err);
return err;
}
data->temp = temp;
return 0;
}
static int lm77_channel_get(const struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct lm77_data *data = dev->data;
if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
lm77_temp_to_sensor_value(data->temp, val);
return 0;
}
static const struct sensor_driver_api lm77_driver_api = {
.attr_set = lm77_attr_set,
.attr_get = lm77_attr_get,
#if LM77_TRIGGER_SUPPORT
.trigger_set = lm77_trigger_set,
#endif /* LM77_TRIGGER_SUPPORT */
.sample_fetch = lm77_sample_fetch,
.channel_get = lm77_channel_get,
};
static int lm77_init(const struct device *dev)
{
const struct lm77_config *config = dev->config;
int err;
#if LM77_TRIGGER_SUPPORT
struct lm77_data *data = dev->data;
#endif /* LM77_TRIGGER_SUPPORT */
if (!device_is_ready(config->i2c.bus)) {
LOG_ERR("I2c bus not ready");
return -EINVAL;
}
err = lm77_write_config(dev, config->config_dt.reg);
if (err < 0) {
LOG_ERR("failed to write configuration (err %d)", err);
return err;
}
#if LM77_TRIGGER_SUPPORT
data->dev = dev;
k_work_queue_start(&data->workq, data->stack, K_THREAD_STACK_SIZEOF(data->stack),
CONFIG_LM77_TRIGGER_THREAD_PRIO, NULL);
k_thread_name_set(&data->workq.thread, "lm77_trigger");
k_work_init(&data->work, lm77_trigger_work_handler);
if (config->int_gpio.port != NULL) {
if (!device_is_ready(config->int_gpio.port)) {
LOG_ERR("INT GPIO not ready");
return -EINVAL;
}
err = gpio_pin_configure_dt(&config->int_gpio, GPIO_INPUT);
if (err < 0) {
LOG_ERR("failed to configure INT GPIO (err %d)", err);
return err;
}
gpio_init_callback(&data->int_gpio_cb, lm77_int_gpio_callback_handler,
BIT(config->int_gpio.pin));
err = gpio_add_callback(config->int_gpio.port, &data->int_gpio_cb);
if (err < 0) {
LOG_ERR("failed to add INT GPIO callback (err %d)", err);
return err;
}
}
#endif /* LM77_TRIGGER_SUPPORT */
return 0;
}
#ifdef CONFIG_PM_DEVICE
static int lm77_pm_control(const struct device *dev, enum pm_device_action action)
{
const struct lm77_config *config = dev->config;
union lm77_reg_config creg = config->config_dt;
int err;
switch (action) {
case PM_DEVICE_ACTION_SUSPEND:
creg.shutdown = 1;
break;
case PM_DEVICE_ACTION_RESUME:
creg.shutdown = 0;
break;
default:
return -ENOTSUP;
}
err = lm77_write_config(dev, creg.reg);
if (err < 0) {
LOG_ERR("failed to write configuration (err %d)", err);
return err;
}
return 0;
}
#endif /* CONFIG_PM_DEVICE */
#if LM77_TRIGGER_SUPPORT
#define LM77_INT_GPIO_INIT(n) .int_gpio = GPIO_DT_SPEC_INST_GET_OR(n, int_gpios, { 0 })
#else /* LM77_TRIGGER_SUPPORT */
#define LM77_INT_GPIO_INIT(n)
#endif /* ! LM77_TRIGGER_SUPPORT */
#ifdef CONFIG_PM_DEVICE
#define LM77_PM_CONTROL_FUNC lm77_pm_control
#else /* CONFIG_PM_DEVICE */
#define LM77_PM_CONTROL_FUNC NULL
#endif /* ! CONFIG_PM_DEVICE */
#define LM77_INIT(n) \
static struct lm77_data lm77_data_##n; \
\
static const struct lm77_config lm77_config_##n = { \
.i2c = I2C_DT_SPEC_INST_GET(n), \
.config_dt = { \
.shutdown = 0, \
.int_mode = DT_INST_NODE_HAS_PROP(n, int_gpios), \
.tcrita_pol = DT_INST_PROP(n, tcrita_inverted), \
.int_pol = DT_INST_PROP(n, int_inverted), \
.fault_queue = DT_INST_PROP(n, enable_fault_queue), \
.reserved = 0, \
}, \
LM77_INT_GPIO_INIT(n) \
}; \
\
DEVICE_DT_INST_DEFINE(n, lm77_init, \
LM77_PM_CONTROL_FUNC, \
&lm77_data_##n, \
&lm77_config_##n, POST_KERNEL, \
CONFIG_SENSOR_INIT_PRIORITY, \
&lm77_driver_api);
DT_INST_FOREACH_STATUS_OKAY(LM77_INIT)