SPINEL_PROP_HOST_POWER_STATE value

Host Power State Format: 'C` Describes the current power state of the host. This property is used by the host to inform the NCP when it has changed power states. The NCP can then use this state to determine which properties need asynchronous updates. Enumeration `spinel_host_power_state_t` defines the valid values (`SPINEL_HOST_POWER_STATE_*`): `HOST_POWER_STATE_OFFLINE`: Host is physically powered off and cannot be woken by the NCP. All asynchronous commands are squelched. `HOST_POWER_STATE_DEEP_SLEEP`: The host is in a low power state where it can be woken by the NCP but will potentially require more than two seconds to become fully responsive. The NCP MUST avoid sending unnecessary property updates, such as child table updates or non-critical messages on the debug stream. If the NCP needs to wake the host for traffic, the NCP MUST first take action to wake the host. Once the NCP signals to the host that it should wake up, the NCP MUST wait for some activity from the host (indicating that it is fully awake) before sending frames. `HOST_POWER_STATE_RESERVED`: This value MUST NOT be set by the host. If received by the NCP, the NCP SHOULD consider this as a synonym of `HOST_POWER_STATE_DEEP_SLEEP`. `HOST_POWER_STATE_LOW_POWER`: The host is in a low power state where it can be immediately woken by the NCP. The NCP SHOULD avoid sending unnecessary property updates, such as child table updates or non-critical messages on the debug stream. `HOST_POWER_STATE_ONLINE`: The host is awake and responsive. No special filtering is performed by the NCP on asynchronous updates. All other values are RESERVED. They MUST NOT be set by the host. If received by the NCP, the NCP SHOULD consider the value as a synonym of `HOST_POWER_STATE_LOW_POWER`. After setting this power state, any further commands from the host to the NCP will cause `HOST_POWER_STATE` to automatically revert to `HOST_POWER_STATE_ONLINE`. When the host is entering a low-power state, it should wait for the response from the NCP acknowledging the command (with `CMD_VALUE_IS`). Once that acknowledgment is received the host may enter the low-power state. If the NCP has the `CAP_UNSOL_UPDATE_FILTER` capability, any unsolicited property updates masked by `PROP_UNSOL_UPDATE_FILTER` should be honored while the host indicates it is in a low-power state. After resuming to the `HOST_POWER_STATE_ONLINE` state, the value of `PROP_UNSOL_UPDATE_FILTER` MUST be unchanged from the value assigned prior to the host indicating it was entering a low-power state.