Patent Publication Number: US-2010115144-A1

Title: Wireless Switch State Using Controller Powered with System in Various Low-Powered States

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to controlling an internal wireless device and an external wireless device when a computer system is in various power states. More particularly, the present invention relates to powering the external wireless device included in an external slot device when the computer system is in a low power state in order to maintain communication with a mobile device. 
     2. Description of the Related Art 
     In an increasingly connected world, computing devices no longer power down completely. Instead, many computing devices enter low power states such as S2/3 (sleep modes) and S4 (hibernate mode). Other devices may be externally connected to a computing device through the computing device&#39;s ports or slots that receive power from the computing device. For example, a laptop computer may have an ExpressCard slot in which a user may insert an ExpressCard. In this example, the ExpressCard may include a wireless transceiver, such as a Bluetooth transceiver, that the computing device utilizes in order to wirelessly communicate with other devices. 
     SUMMARY 
     A computer system detects a power state change and determines that the power state change puts the computer system in a low power state. In turn, the computer system informs an external slot device to enable an external wireless device included in the external slot device. 
     The foregoing is a summary and thus contains, by necessity, simplifications, generalizations, and omissions of detail; consequently, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the present invention, as defined solely by the claims, will become apparent in the non-limiting detailed description set forth below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings, wherein: 
         FIG. 1  is a block diagram of a data processing system in which the methods described herein can be implemented; 
         FIG. 2  is a diagram showing a computer system powering an external slot device in a low power state; 
         FIG. 3  is a table showing various configurations of an internal wireless device and components included on an external slot device; 
         FIG. 4A  is a diagram showing a computer system communicating with a mobile device in a high power state through an internal wireless device; 
         FIG. 4B  is a diagram showing a computer system communicating with a mobile device in a low power state through an external slot device&#39;s external wireless device; 
         FIG. 5  is a high-level flowchart showing steps taken in configuring a computer system&#39;s internal wireless device and an external wireless device based upon the computer system&#39;s power state and wireless state; 
         FIG. 6  is a flowchart showing steps taken in configuring an internal wireless device and an external wireless device based upon a power state change; and 
         FIG. 7  is a flowchart showing steps taken in configuring an internal wireless device and an external wireless device based upon a wireless state change. 
     
    
    
     DETAILED DESCRIPTION 
     Certain specific details are set forth in the following description and figures to provide a thorough understanding of various embodiments of the invention. 
     Certain well-known details often associated with computing and software technology are not set forth in the following disclosure, however, to avoid unnecessarily obscuring the various embodiments of the invention. Further, those of ordinary skill in the relevant art will understand that they can practice other embodiments of the invention without one or more of the details described below. Finally, while various methods are described with reference to steps and sequences in the following disclosure, the description as such is for providing a clear implementation of embodiments of the invention, and the steps and sequences of steps should not be taken as required to practice this invention. Instead, the following is intended to provide a detailed description of an example of the invention and should not be taken to be limiting of the invention itself. Rather, any number of variations may fall within the scope of the invention, which is defined by the claims that follow the description. 
     The following detailed description will generally follow the summary of the invention, as set forth above, further explaining and expanding the definitions of the various aspects and embodiments of the invention as necessary. To this end, this detailed description first sets forth a computing environment in  FIG. 1  that is suitable to implement the software and/or hardware techniques associated with the invention. 
       FIG. 1  illustrates information handling system  100 , which is a simplified example of a computer system capable of performing the computing operations described herein. Information handling system  100  includes one or more processors  110  coupled to processor interface bus  112 . Processor interface bus  112  connects processors  110  to Northbridge  115 , which is also known as the Memory Controller Hub (MCH). Northbridge  115  connects to system memory  120  and provides a means for processor(s)  110  to access the system memory. Graphics controller  125  also connects to Northbridge  115 . In one embodiment, PCI Express bus  118  connects Northbridge  115  to graphics controller  125 . Graphics controller  125  connects to display device  130 , such as a computer monitor. 
     Northbridge  115  and Southbridge  135  connect to each other using bus  119 . In one embodiment, the bus is a Direct Media Interface (DMI) bus that transfers data at high speeds in each direction between Northbridge  115  and Southbridge  135 . In another embodiment, a Peripheral Component Interconnect (PCI) bus connects the Northbridge and the Southbridge. Southbridge  135 , also known as the I/O Controller Hub (ICH) is a chip that generally implements capabilities that operate at slower speeds than the capabilities provided by the Northbridge. Southbridge  135  typically provides various busses used to connect various components. These busses include, for example, PCI and PCI Express busses, an ISA bus, a System Management Bus (SMBus or SMB), and/or a Low Pin Count (LPC) bus. The LPC bus often connects low-bandwidth devices, such as boot ROM  196  and “legacy” I/O devices (using a “super I/O” chip). The “legacy” I/O devices ( 198 ) can include, for example, serial and parallel ports, keyboard, mouse, and/or a floppy disk controller. The LPC bus also connects Southbridge  135  to Trusted Platform Module (TPM)  195 . Other components often included in Southbridge  135  include a Direct Memory Access (DMA) controller, a Programmable Interrupt Controller (PIC), and a storage device controller, which connects Southbridge  135  to nonvolatile storage device  185 , such as a hard disk drive, using bus  184 . 
     ExpressCard  155  is a slot that connects hot-pluggable devices to the information handling system. ExpressCard  155  supports both PCI Express and USB connectivity as it connects to Southbridge  135  using both the Universal Serial Bus (USB) the PCI Express bus. Southbridge  135  includes USB Controller  140  that provides USB connectivity to devices that connect to the USB. These devices include webcam (camera)  150 , infrared (IR) receiver  148 , keyboard and trackpad  144 , and Bluetooth device  146 , which provides for wireless personal area networks (PANs). USB Controller  140  also provides USB connectivity to other miscellaneous USB connected devices  142 , such as a mouse, removable nonvolatile storage device  145 , modems, network cards, ISDN connectors, fax, printers, USB hubs, and many other types of USB connected devices. While removable nonvolatile storage device  145  is shown as a USB-connected device, removable nonvolatile storage device  145  could be connected using a different interface, such as a Firewire interface, etcetera. 
     Wireless Local Area Network (LAN) device  175  connects to Southbridge  135  via the PCI or PCI Express bus  172 . LAN device  175  typically implements one of the IEEE 802.11 standards of over-the-air modulation techniques that all use the same protocol to wireless communicate between information handling system  100  and another computer system or device. Optical storage device  190  connects to Southbridge  135  using Serial ATA (SATA) bus  188 . Serial ATA adapters and devices communicate over a high-speed serial link. The Serial ATA bus also connects Southbridge  135  to other forms of storage devices, such as hard disk drives. Audio circuitry  160 , such as a sound card, connects to Southbridge  135  via bus  158 . Audio circuitry  160  also provides functionality such as audio line-in and optical digital audio in port  162 , optical digital output and headphone jack  164 , internal speakers  166 , and internal microphone  168 . Ethernet controller  170  connects to Southbridge  135  using a bus, such as the PCI or PCI Express bus. Ethernet controller  170  connects information handling system  100  to a computer network, such as a Local Area Network (LAN), the Internet, and other public and private computer networks. 
     While  FIG. 1  shows one information handling system, an information handling system may take many forms. For example, an information handling system may take the form of a desktop, server, portable, laptop, notebook, or other form factor computer or data processing system. In addition, an information handling system may take other form factors such as a personal digital assistant (PDA), a gaming device, ATM machine, a portable telephone device, a communication device or other devices that include a processor and memory. 
     The Trusted Platform Module (TPM  195 ) shown in  FIG. 1  and described herein to provide security functions is but one example of a hardware security module (HSM). Therefore, the TPM described and claimed herein includes any type of HSM including, but not limited to, hardware security devices that conform to the Trusted Computing Groups (TCG) standard, and entitled “Trusted Platform Module (TPM) Specification Version 1.2.” 
       FIG. 2  is a diagram showing a computer system powering an external slot device in a low power state. Computer system  200 , such as a laptop computer, is capable of communicating with other wireless devices (e.g., mobile phones, printers, etc.) through a wireless network, such a Bluetooth network. Computer system  200  includes internal wireless device  250  and also includes a slot (e.g., ExpressCard slot, PCMCIA card slot, etc.) in which to insert external slot device  210 . The example shown in  FIG. 2  shows that external slot device  210  includes external processor  215  and external wireless device  220 . The invention described herein allows computer system  200  to utilize internal wireless device  250  during high power states and utilize external wireless device  220  during low power states (e.g., S 3 , S 4 , or S 5  states). Due to particular wireless standards, the invention described herein prohibits both internal wireless device  250  and external wireless device  220  to be enabled simultaneously. 
     When computer system  200  is in the high power state, input/output controller hub (ICH)  290  acts as a USB host and enables/disables internal wireless device  250  based upon software wireless state changes. For example, a user may enable or disable the computer system  200 &#39;s wireless state through a graphical user interface. When this occurs, ICH  290  sends wireless state change information to internal wireless device  250  and external processor  215  through a USB bus. Although computer system  200  is in a high power state, external processor  215  still logs the wireless state change for later use when computer system  200  enters a low power state. In one embodiment, computer system  200  may send the wireless state change indicator to external slot device  210  through other means, such as a hardwired signal. 
     Computer system  200  includes embedded controller  230 , which monitors wireless hardware switch  270  for wireless state changes. For example, computer system  200  may include a button that a user may depress in order to enable or disable the wireless state. Embedded controller  230  utilizes system management bus (SMBus)  275  to send wireless state change indicators information to external processor  215 . In turn, external processor  215  logs the wireless state change information and, when computer system is in a low power state, external processor  215  enables/disables external wireless device accordingly (see  FIG. 7  and corresponding text for further details). In one embodiment, computer system  200  may send the wireless state change indicator to external slot device  210  through other means, such as a hardwired signal. 
     Embedded controller  260  also controls power to internal wireless device  250  via power control  280  based upon computer system  200 &#39;s power state. In addition, embedded controller  230  informs power controller  260  as to computer system  200 &#39;s power state, such as a high power state or low power state. In turn, power controller  260  supplies power to external slot device  210  through power line  265  when computer system  200  is in the high power state and the low power state. When in the high power state, external processor  215  disables external wireless device  220  via power control  270  and logs wireless state change commands from embedded controller  230  and ICH  290 . When in the low power state, external processor  215  enables external wireless device  220  based upon computer system  200 &#39;s wireless state. 
       FIG. 3  is a table showing various configurations of an internal wireless device and components included on an external slot device. Table  300  includes rows  350  and  360 , which include an internal wireless device&#39;s state and an external device&#39;s state when a computer system is in either a high power state (row  350 ) or a low power state (row  360 ). 
     Row  350  shows that when the computer system is in a high power state, the internal wireless device&#39;s state is dependent upon the computer system&#39;s wireless state based upon hardware or software wireless control (column  320 ). Column  330  shows that the external device&#39;s processor is on in order to receive and log wireless state changes from the computer system. And, although the external device&#39;s processor is on, the external wireless device remains off in order to not conflict with the internal wireless device (column  340 ). 
     Row  360  shows that when the computer system is in a low power state, the internal device is turned off (column  320 ). Column  330  shows that the external device&#39;s processor remains on in the low power state, and column  340  shows that the external wireless device&#39;s state is dependent upon a wireless state prior to entering the low power state, and is also dependent upon the computer system&#39;s hardware wireless state control. For example, if a computer system&#39;s wireless state was enabled prior to entering the low power state, the external device&#39;s processor enables the external wireless device once the computer system enters the low power state. In this example, if a user depresses a wireless control switch to disable the wireless state, the external device&#39;s processor, in turn, disables the external wireless device. 
       FIG. 4A  is a diagram showing a computer system communicating with a mobile device in a high power state through an internal wireless device. Computer system  200  includes internal wireless device  250  and a slot that is adapted to receive external slot device  210 , which includes external processor  215  and external wireless device  220 . 
       FIG. 4A  shows that when computer system  200  is in a high power state, computer system  200  communicates with mobile device  410  through internal wireless device  250 . In order to ensure that external wireless device  220  does not interfere with these communications, external processor  215  turns off external wireless device  220  when computer system  200  is in the high power state. 
       FIG. 4B  is a diagram showing a computer system communicating with a mobile device in a low power state through an external slot device&#39;s external wireless device. When computer system  200  enters a low power state,  FIG. 4B  shows that computer system  200  communicates with mobile device  410  through external wireless device  220 . In order to ensure that internal wireless device  250  does not interfere with these communications, computer system  200  turns off internal wireless device  250  when computer system  200  is in the low power state. 
       FIG. 5  is a high-level flowchart showing steps taken in configuring a computer system&#39;s internal wireless device and an external wireless device based upon the computer system&#39;s power state and wireless state. A computer system communicates with a mobile device either through the computer system&#39;s internal wireless device or the computer system&#39;s external wireless device, such as an ExpressCard. In one embodiment, in order to adhere to particular wireless standards, the computer system ensures that both wireless devices are not enabled concurrently. Meaning, either the internal wireless device is enabled or the external wireless device is enabled, but both devices are not simultaneously enabled. 
     Processing commences at  500 , whereupon the computer system powers up in a high power state at step  510 . At step  520 , processing detects a wireless state, such as through a hardware wireless control (switch) or a software wireless control (e.g., user interface window). Processing configures the computer system&#39;s internal wireless device at step  525 , such as enabling an internal Bluetooth device. Processing, at step  530 , sends the detected wireless state to external slot device  210 . External slot device  210  is the same as that shown in  FIG. 2 , such as an ExpressCard. Since the computer system is currently in a high power state, a processor included in external slot device  210  logs the wireless state such that when the computer system enters a low power state, the processor may retrieve the logged wireless state and enable/disable the external slot device  210 &#39;s wireless device based upon the logged wireless state (see  FIG. 6  and corresponding text for further details). 
     Processing waits for a state change at step  540 , which may be a power state change (e.g., high power to low power) or a wireless state change (e.g., enabled to disabled). When processing detects a state change, a determination is made as to whether the state change was a power state change (decision  550 ). If the state change was a power state change, decision  550  branches to “Yes” branch  552  whereupon processing proceeds through a series of steps to communicate the state changes to external slot device  210  as well as configure the computer system&#39;s internal wireless device accordingly (pre-defined process block  555 , see  FIG. 6  and corresponding text for further details). 
     On the other hand, if the state change is not a power state change, decision  550  branches to “No” branch  558  whereupon a determination is made as to whether the state change is a wireless state change (decision  560 ). For example, a user may have depressed a wireless control switch to turn off the wireless device. If the state change is a wireless state change, decision  560  branches to “Yes” branch  562 , whereupon processing proceeds through a series of steps to communicate the wireless state changes to external slot device  210  as well as configure the computer system&#39;s internal wireless device accordingly (pre-defined process block  565 , see  FIG. 7  and corresponding text for further details). 
     A determination is made as to whether to continue monitoring the computer system&#39;s state changes (decision  570 ). If processing should continue monitoring state changes, decision  570  branches to “Yes” branch  572 , which loops back to continue monitoring state changes and performing actions accordingly. This looping continues until processing should terminate, such as when the computer system turns off, at which point decision  570  branches to “No” branch  578  and processing ends at  580 . 
       FIG. 6  is a flowchart showing steps taken in configuring an internal wireless device and an external wireless device based upon a power state change. 
     Processing detected a power state change in  FIG. 5 , such as a computer system transitioning from a high power state to a low power state (e.g., S 3 , S 4 , or S 5  state).  FIG. 6  shows steps taken in the computer system&#39;s embedded controller configuring an internal wireless device accordingly as well as an external slot device&#39;s processor configuring an external wireless device accordingly. 
     Embedded controller processing commences at  600 , whereupon the embedded controller informs the external slot device of the power state change at step  605 . External device processing commences at  650 , whereupon the external device receives the power state change at step  655 . 
     In one embodiment, the embedded controller sends a power state change indicator to the external slot device, which may be a software message or a hardwired signal. 
     At the embedded controller, the embedded controller determines whether the new power state is a low power state or a high power state (decision  610 ). If the new power state is a low power state, decision  610  branches to “Low Power” branch  618 , whereupon the embedded controller turns off the internal wireless device at step  615  and returns at  620 . 
     On the other hand, if the new power state is a high power state, decision  610  branches to “High Power” state  612 , whereupon processing retrieves a wireless state at step  625 . In one embodiment, the wireless state is dependent upon the combination of a hardware wireless control and a software wireless control. 
     A determination is made as to whether the wireless state is in a wireless enabled state or a wireless disabled state (decision  630 ). If the wireless state is in a wireless enabled state, decision  630  branches to “Yes” branch  632  whereupon processing enables the internal wireless device at step  635  and returns at  640 . On the other hand, if the wireless state is in a wireless disabled state, decision  630  branches to “No” branch  638 , thus keeping the internal wireless device disabled and returning at  640 . 
     At the external device, the external device determines whether the new power state is a low power state or a high power state (decision  660 ). If the new power state is a high power state, decision  660  branches to “High Power” branch  668 , whereupon the external device turns off the external wireless device at step  665  and ends at  670 . As can be seen, steps  615  and  665  ensure that both the internal wireless device and the external wireless device are not turned on at the same time. 
     On the other hand, if the new power state is a low power state, decision  660  branches to “Low Power” state  662 , whereupon processing retrieves a logged wireless state at step  675 . The external device logs the wireless state regardless of whether the computer system is in the low power state or the high power state in order for the external device to place the external wireless device in the correct wireless state when the computer system changes to the low power state (see  FIG. 7  and corresponding text for further details). 
     A determination is made as to whether the wireless state is in a wireless enabled state or a wireless disabled state (decision  680 ). If the wireless state is in a wireless enabled state, decision  680  branches to “Yes” branch  682  whereupon processing enables the external wireless device at step  685  and ends at  690 . On the other hand, if the wireless state is in a wireless disabled state, decision  680  branches to “No” branch  688 , thus keeping the external wireless device disabled. 
       FIG. 7  is a flowchart showing steps taken in configuring an internal wireless device and an external wireless device based upon a wireless state change. Processing detected a wireless state change in  FIG. 5 , such as transitioning from a wireless enabled state to a wireless disabled state.  FIG. 7  shows steps taken in the computer system&#39;s embedded controller configuring the internal wireless device accordingly as well as the external slot device&#39;s processor configuring the external wireless device accordingly. 
     Embedded controller processing commences at  700 , whereupon the embedded controller sends the wireless state change to the external device at step  705  and logs the new wireless state at step  710 . External device processing commences at  750 , whereupon the external device receives the wireless state change at step  755  and logs the new wireless state at step  760 . As can be seen, steps  705 - 710  and  755 - 760  occur regardless of the computer system&#39;s power state due to the fact that both the embedded controller and the external device are required to track the wireless state change in order to properly enable/disable their corresponding wireless device when a power state change occurs (see  FIG. 6  and corresponding text for further details). 
     At the embedded controller, a determination is made as to whether the power state is in a high power state or a low power state (decision  715 ). If the power state is in a low power state, decision  715  branches to “Low Power” branch  717  whereupon processing returns at  720  due to the fact that in a low power state, the internal wireless device is turned off. 
     On the other hand, if the power state is in a high power state, decision  715  branches to “High Power” branch  719 , whereupon a determination is made as to the new wireless state (decision  730 ). If the new wireless state is a wireless enabled state, decision  730  branches to “Enable” branch  738  whereupon processing turns on the internal wireless device at step  740  and returns at  745 . On the other hand, if the new wireless state is a wireless disabled state, decision  730  branches to “Disable” state  732 , whereupon processing turns off the internal device at step  735  and returns at  745 . 
     At the external device, a determination is made as to whether the power state is in a high power state or a low power state (decision  765 ). If the power state is in a high power state, decision  765  branches to “High Power” branch  767  whereupon processing ends at  770  due to the fact that in a high power state, the external wireless device is turned off. 
     On the other hand, if the power state is in a low power state, decision  765  branches to “Low Power” branch  769 , whereupon a determination is made as to the new wireless state (decision  780 ). If the new wireless state is a wireless enabled state, decision  780  branches to “Enable” branch  788  whereupon processing turns on the external wireless device at step  790  and ends at  795 . On the other hand, if the new wireless state is a wireless disabled state, decision  780  branches to “Disable” state  782 , whereupon processing turns off the internal device at step  785  and ends at  795 . 
     One of the preferred implementations of the invention is a client application, namely, a set of instructions (program code) or other functional descriptive material in a code module that may, for example, be resident in the random access memory of the computer. Until required by the computer, the set of instructions may be stored in another computer memory, for example, in a hard disk drive, or in a removable memory such as an optical disk (for eventual use in a CD ROM) or floppy disk (for eventual use in a floppy disk drive). Thus, the present invention may be implemented as a computer program product for use in a computer. In addition, although the various methods described are conveniently implemented in a general purpose computer selectively activated or reconfigured by software, one of ordinary skill in the art would also recognize that such methods may be carried out in hardware, in firmware, or in more specialized apparatus constructed to perform the required method steps. Functional descriptive material is information that imparts functionality to a machine. Functional descriptive material includes, but is not limited to, computer programs, instructions, rules, facts, definitions of computable functions, objects, and data structures. 
     While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, that changes and modifications may be made without departing from this invention and its broader aspects. Therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be understood by those with skill in the art that if a specific number of an introduced claim element is intended, such intent will be explicitly recited in the claim, and in the absence of such recitation no such limitation is present. For non-limiting example, as an aid to understanding, the following appended claims contain usage of the introductory phrases “at least one” and “one or more” to introduce claim elements. However, the use of such phrases should not be construed to imply that the introduction of a claim element by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim element to inventions containing only one such element, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an”; the same holds true for the use in the claims of definite articles.