【zephyr】PM 电源管理

1. CONFIG配置总开关

CONFIG_SYS_POWER_MANAGEMENT=y
CONFIG_DEVICE_POWER_MANAGEMENT=y
CONFIG_DEVICE_IDLE_PM=y

2. 设备注册API接口

设备

/**
 * @brief Device PM info
 *
 * @param dev pointer to device structure
 * @param lock lock to synchronize the get/put operations
 * @param enable device pm enable flag
 * @param usage device usage count
 * @param fsm_state device idle internal power state
 * @param event event object to listen to the sync request events
 * @param signal signal to notify the Async API callers
 */
struct device_pm {
	struct device *dev;
	struct k_sem lock;
	bool enable;
	atomic_t usage;
	atomic_t fsm_state;
	struct k_work work;
	struct k_poll_event event;
	struct k_poll_signal signal;
};

/**
 * @brief Static device information (In ROM) Per driver instance
 *
 * @param name name of the device
 * @param init init function for the driver
 * @param config_info address of driver instance config information
 */
struct device_config {
	const char *name;
	int (*init)(struct device *device);
#ifdef CONFIG_DEVICE_POWER_MANAGEMENT
	int (*device_pm_control)(struct device *device, u32_t command,
				 void *context, device_pm_cb cb, void *arg);
	struct device_pm *pm;
#endif
	const void *config_info;
};

/**
 * @brief Runtime device structure (In memory) Per driver instance
 * @param device_config Build time config information
 * @param driver_api pointer to structure containing the API functions for
 * the device type. This pointer is filled in by the driver at init time.
 * @param driver_data driver instance data. For driver use only
 */
struct device {
	struct device_config *config;
	const void *driver_api;
	void *driver_data;
#if defined(__x86_64) && __SIZEOF_POINTER__ == 4
	/* The x32 ABI hits an edge case.  This is a 12 byte struct,
	 * but the x86_64 linker will pack them only in units of 8
	 * bytes, leading to alignment problems when iterating over
	 * the link-time array.
	 */
	void *padding;
#endif
};

API 接口定义

#define DEVICE_DEFINE(dev_name, drv_name, init_fn, pm_control_fn,	  \
		      data, cfg_info, level, prio, api)			  \
	static struct device_pm _CONCAT(__pm_, dev_name) __used           \
							= {               \
		.usage = ATOMIC_INIT(0),                                  \
		.lock = _K_SEM_INITIALIZER(                               \
				_CONCAT(__pm_, dev_name).lock, 1, 1),     \
		.signal = K_POLL_SIGNAL_INITIALIZER(                      \
				_CONCAT(__pm_, dev_name).signal),         \
		.event = K_POLL_EVENT_INITIALIZER(K_POLL_TYPE_SIGNAL,     \
				K_POLL_MODE_NOTIFY_ONLY,                  \