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drivers: sensor: Add PM support to LM75 digital temperature sensor

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Add support for device power management. When the sensor
is not powered, the fetch function will fail. When the
sensor is not connected to a power domain, it will behave
as usual.

Signed-off-by: Albert Jakieła <aja@semihalf.com>
This commit is contained in:
Albert Jakieła 2023-08-01 12:58:05 +00:00 • committed by Maureen Helm
commit dd4ef7d2b5
1 changed files with 52 additions and 7 deletions
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59
drivers/sensor/lm75/lm75.c
View file

@ -10,6 +10,8 @@
#include <zephyr/devicetree.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/pm/device.h>
#include <zephyr/pm/device_runtime.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(LM75, CONFIG_SENSOR_LOG_LEVEL);
@ -62,14 +64,26 @@ static int lm75_sample_fetch(const struct device *dev,
{
struct lm75_data *data = dev->data;
const struct lm75_config *cfg = dev->config;
enum pm_device_state pm_state;
int ret;
(void)pm_device_state_get(dev, &pm_state);
if (pm_state != PM_DEVICE_STATE_ACTIVE) {
ret = -EIO;
return ret;
}
switch (chan) {
case SENSOR_CHAN_ALL:
case SENSOR_CHAN_AMBIENT_TEMP:
return lm75_fetch_temp(cfg, data);
ret = lm75_fetch_temp(cfg, data);
break;
default:
return -ENOTSUP;
ret = -ENOTSUP;
break;
}
return ret;
}
static int lm75_channel_get(const struct device *dev,
@ -96,21 +110,52 @@ static const struct sensor_driver_api lm75_driver_api = {
int lm75_init(const struct device *dev)
{
const struct lm75_config *cfg = dev->config;
int ret = 0;
if (device_is_ready(cfg->i2c.bus)) {
return 0;
if (!device_is_ready(cfg->i2c.bus)) {
LOG_ERR("I2C dev not ready");
return -ENODEV;
}
LOG_ERR("I2C dev not ready");
return -ENODEV;
#ifdef CONFIG_PM_DEVICE_RUNTIME
pm_device_init_suspended(dev);
ret = pm_device_runtime_enable(dev);
if (ret < 0 && ret != -ENOTSUP) {
LOG_ERR("Failed to enable runtime power management");
return ret;
}
#endif
return ret;
}
#ifdef CONFIG_PM_DEVICE
static int lm75_pm_action(const struct device *dev, enum pm_device_action action)
{
switch (action) {
case PM_DEVICE_ACTION_TURN_ON:
case PM_DEVICE_ACTION_RESUME:
case PM_DEVICE_ACTION_TURN_OFF:
case PM_DEVICE_ACTION_SUSPEND:
break;
default:
return -ENOTSUP;
}
return 0;
}
#endif
#define LM75_INST(inst) \
static struct lm75_data lm75_data_##inst; \
static const struct lm75_config lm75_config_##inst = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
}; \
SENSOR_DEVICE_DT_INST_DEFINE(inst, lm75_init, NULL, &lm75_data_##inst, \
PM_DEVICE_DT_INST_DEFINE(inst, lm75_pm_action); \
SENSOR_DEVICE_DT_INST_DEFINE(inst, lm75_init, PM_DEVICE_DT_INST_GET(inst), &lm75_data_##inst, \
&lm75_config_##inst, POST_KERNEL, \
CONFIG_SENSOR_INIT_PRIORITY, &lm75_driver_api);