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- To get started, right-click the Synaptics or ELAN touchpad device under the “Mice and other pointing devices” category in Device Manager, and then select the “Update driver” command. Click the “Browse my computer for driver software” option.
- Go to Device Manager (right click on My Computer, choose Manage and then find Device Manager in the left panel), or right click on Start Menu for Windows 10 and select Device Manager 3.
- Download Multifunction Device for Windows to modem driver. Download Multifunction Device for Windows to modem driver. Join or Sign In. Sign in to add and modify your software.
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December 17, 2020
This article was contributed by Marta Rybczyńska
Device drivers usually live within a single kernel subsystem. Sometimes,however, developers need to handle functionalities outside of this model.Consider, for example, a network interface card (NIC) exposing both Ethernet andRDMA functionalities. There is one hardware block, but two drivers for thetwo functions. Those drivers need to work within their respectivesubsystems, but they must also share access to the same hardware. There isno standard way in current kernels to connect those drivers together, sodevelopers invent ad-hoc methods to handle the interaction betweenthem. Recently, Dave Ertman posteda patch set introducing a new type of a bus, called the 'auxiliary bus', toaddress this problem.
Complex devices
Linux already includes a number of drivers for multi-functiondevices. One of the ways to support them is the Multi-FunctionDevices (MFD) subsystem. It handles independent devices 'glued'together into one hardware block which may contain some sharedresources. MFD allows access to device registers either directly, or usinga common bus. In this second case, it conveniently multiplexes accesses onInter-Integrated Circuit(I2C) or SerialPeripheral Interface (SPI) buses. As the MFD sub-devices are separate,MFD drivers do not share a common state.
The devices Ertman addresses do not fit well into the MFD model.Devices using the auxiliary bus provide subsets of the capabilities of asingle hardware device. They do not expose separate register sets for eachfunction; thus they cannot be described by devicetrees or discovered byACPI. Their drivers need to share access to the hardware. Events concerning allsub-functionalities (like power management) need to be properly handled byall drivers. These devices will often be specialized processors runningfirmware and communicating with the host system (and the Linux drivers) bymessaging. The available functions may not be known in advance, and thusmust be discovered at run time.
The documentationpatch in the auxiliary bus series cites a number of examples. The SoundOpen Firmware (SOF) driver interacts with a single device exposinginterfaces like HDMI output, microphones, speakers, testing, and debughooks. NICs implementing both Ethernet and RDMA may need a driversupporting a common part of the functionalities, and then the specificEthernet and RDMA drivers can implement specific parts on top of that.
Current kernels do not have a generic way to describe dependenciesbetween drivers for this kind of device. A solution to the problem could beto have a way to attach secondary drivers to the primaryone; this is exactly what the auxiliary bus implements.
Auxiliary devices and drivers
The patch set introduces two main concepts: The 'auxiliary device' and'auxiliary driver'. These implement the relationship between the main andthe secondary drivers. The main driver maintains the device state, allocating and managing all shared data. It also unregisters all secondarydrivers when shutting down. Secondary drivers, instead, handle theinteractions with the specific subsystem they are implementing a devicefor.
Each main driver may expose a number of functionalities (devices) forsecondary drivers. Only one secondary driver can attach to each of thosefunctionalities.
The main driver creates an auxiliary device, represented by structauxiliary_device:
The combination of name and id must be unique; thecomplete device name is a combination of the module name and those twofields, connected by dots (.). That yields a result likemodname.device_name.id.
The developer embeds this structure in the device structure ofthe main driver, with all shared data necessary for the communicationbetween the main driver and secondary drivers. They may also addsupplementary callbacks.
The sequence to initialize the main driver contains two steps. The firstone is to call auxiliary_device_init():
It verifies the arguments and returns anerror code if need be; in such case the initialization of the deviceshould be aborted.If the first call succeeds, the second step is to call the macroauxiliary_device_add() with the initialized device; this willset up the device name and register the deviceitself.
The unregistration procedure also has two steps, consisting of calls toauxiliary_device_uninit() (necessary from the point whenauxiliary_device_init() has succeeded) andauxiliary_device_delete(). Those functions have the followingprototypes:
This two-step approach was implemented inresponse to comments on earlier versions of the patch set. It allows the driver to allocate itsown data between auxiliary_device_init() andauxiliary_device_add() with a possibility to free it correctly inthe case of a failure.
The secondary devices, which will connect to the main driver,are represented by struct auxiliary_driver:
This structure includes a number of callbacks to manage thedevice's life cycle, and the id_table containing names of thedevices the driver can bind with. All callbacks receive pointers to theparent's auxiliary_device, allowing access to the shareddata.
The secondary devices are set up with auxiliary_driver_register():
This function requires the probe() callback and theid_table to be filled in. When successful, it causes aprobe() callback call for any matching devices. The secondarydevices can access the shared data using container_of() and theauxiliary_device structure.
When unregistering a driver, the developer should callauxiliary_driver_unregister():
First users
Together with the auxiliary bus implementation, Ertman postedchanges to the SOF driver. The modified driver uses thisinfrastructure to implementa test driver, and aprobes driver, allowing the creation of a new virtual audio device thatcan tap into the pipeline and allow listening in at any point.
Another user can be found in the networking subsystem; Leon Romanovskyposteda conversion of the mlx5 driver to use the auxiliary bus. The updateddriver creates network, VDPA, and RDMAdrivers for one physical device. Those changes allowthe removal of a bunch of custom driver code. Parav Pandit followed upby using this functionality to implement device sub-functions.
The patch set has come to its fourth iteration in its current form, andwitnessed a number of earlier ones under the names of ancillaryand virtualbus.The development of the auxiliary bus patch set took time, and it createddependencies in other work. This caused a fair amount of pressure to get itupstream, and that led to some pushing on thelist. In an attempt to push things forward, Dan Williams repostedthe patch set, stating that 'it looks good to me and several otherstakeholders'. After a review from GregKroah-Hartman, the auxiliary bus code was merged into the mainline for the5.11 kernel release.| Index entries for this article | |
|---|---|
| Kernel | Auxiliary bus |
| Kernel | Device drivers/Support APIs |
| GuestArticles | Rybczynska, Marta |
(Log in to post comments) Universal Devices ISY Driver for ELAN
- Description
- Supported Models
- Intrinsic Connected
What does this driver do?
This Universal Devices ISY Driver for ELAN allows an Elan system to communicate with a Universal Devices ISY bridge via Ethernet for lighting control.
Features:
- Switch, Dimming & Fan: Where supported this driver allows for switch, dimming and Fan control. 4 position (3 speed and off) fan controllers are treated as dimmer devices – 0 is off, 1-33 is speed 1, 34-66 is speed 2 and 67-100 is speed 3
- Scenes: Auto populates scenes that are setup
- Auto Discovery: The driver will find all compatible lighting devices on the bridge.
- Official manufacturer endorsed driver
- Driver uses Intrinsic(Athena) technology for key free licensing, update alerts and enhanced support
Current version number: 20.12.4
Our Universal Devices ISY Driver for ELAN is compatible with:
- ISY994i
- ISY994i compatible devices including lighting and fans
The Intrinsic difference
Our drivers are all developed in-house, in the UK so you can be sure of the highest reliability and responsiveness when updates are required. We never use open source code or code libraries. All of our drivers are thoroughly tested in-house as well as externally through our Beta Programme before being offered on our website.
Support
All of our drivers/modules are supported free of charge through our Online Support system. We offer comprehensive support for all of our software that requires the purchase of a license key for as long as they are listed on the Intrinsic Dev website. If it’s your first time installing a driver or if you believe there is a technical problem simply submit a ticket via our Online Support system.
Enhanced support
We also offer Enhanced Remote Support for each control platform. This support is charged in 30 minute intervals where we are pleased to advise on anything that falls outside of standard driver queries, including, but not limited to, driver installation, wider system integration/programming, general training and system design.
License
All of our software is available to download free of charge but will require licensing to function. Unless specifically noted only one license is required per controller/processor. You can run as many devices as required up to the limit supported by your chosen control platform.
Easy setup
All of our drivers/modules come with comprehensive Integration Notes to ensure the easiest possible set up of our software. Many also have Installation Tutorial videos to further assist you. Please ensure you refer to these resources each time you install a new driver/module.
Drivers Elan Multifunction Devices Wireless
Feedback
If you have any suggestions on new features or changes you would like to see to a driver/module then please let us know via our Online Support system.
Multifunction Devices Reviews
Trackback URLhttps://www.intrinsicdev.com/downloads/universal-devices-isy-driver-for-elan/trackback/