Claims:I/WE CLAIM:

1. An embedded controller chip having interfaces to wake itself up from a low power mode, the embedded controller chip comprising:
a first interface to couple to the platform controller chip, the first interface to receive a wake-up indication to wake up the embedded controller chip from a low power mode; and
a keyboard system controller (KSC) interface to couple to a matrix keyboard, the KSC interface to provide an indication to wake up the embedded controller chip from the low power mode.

2. The embedded controller chip of claim 1 comprises a low pin count (LPC) interface to couple to a platform controller chip.

3. The embedded controller chip of claim 2 comprises a second interface to communicate with a BIOS.

4. The embedded controller chip of claim 3, wherein the BIOS is to detect an operating system (OS) access request to the embedded controller chip.

5. The embedded controller chip of claim 4, wherein the BIOS is to defer the OS access request until the LPC interface is up and functional.

6. The embedded controller chip of claim 3 comprises a third interface to provide a GPIO interface for the wake-up indication.
, Description:BACKGROUND

Field

Embodiments may relate to communicating with an embedded controller (EC).

Background

An electronic device may operate in different states (or modes) such as a normal state and a sleep state. The use of different states (or modes) may be to conserve battery power.

BRIEF DESCRIPTION OF THE DRAWINGS

Arrangements and embodiments may be described in detail with reference to the following drawings in which like reference numerals refer to like elements and wherein:

FIG. 1 is a diagram of components of an electronic device according to an example embodiment;

FIG. 2 is a state diagram showing logical states, transition paths and events in between different states according to an example embodiment;

FIG. 3 is a flowchart showing operations for handling events that occur when transitioning from one state to another state according to an example embodiment;

FIG. 4 is a flowchart showing operations of a handler invoked by a change in state of a signal driven by an EC according to an example embodiment;

FIG. 5 is a flowchart showing operations of a handler that is invoked by operating system (OS) accesses to an EC according to an example embodiment.

DETAILED DESCRIPTION

In the following detailed description, like numerals and characters may be used to designate identical, corresponding and/or similar components in differing figure drawings. Further, in the detailed description to follow, example sizes/models/values/ ranges may be given although embodiments are not limited to the same. Where specific details are set forth in order to describe example embodiments, it should be apparent to one skilled in the art that embodiments may be practiced without these specific details.

An electronic device may operate in many different modes. One operating mode is a User Absent Mode (UAM). The user absent mode is a mode in which a system (or device) is up and running, but user interfaces (e.g. displays, input devices) are not in use. The user absent mode may be used rather than a sleep mode or a standby mode.

In order to support a user absent mode, an electronic device may need to stay in a user absent mode for a particular length of time, and still be usable. However, this may decrease power from a battery over time. This may mean that an electronic device may consume less than a prescribed amount over this time. The user absent mode may also be called a low power mode (LPM).