Melec Multifunction Devices Driver

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  1. Melec Multifunction Devices Driver
  2. Melec Multifunction Devices Driver Wireless
  3. Melec Multifunction Devices Driver Updater
  4. Melec Multifunction Devices Driver Scanner

December 17, 2020

This article was contributed by Marta Rybczyńska

Gestetner supply a number of driver alternatives with their high-end printers, copiers, and multifunction devices (e.g. DSc338), usually including PCL5 and Postscript. PaperCut Software has tested recent releases of the Postscript and PCL drivers and found these are compatible. Multifunction USB Network Server, 1-port Network USB Hub, NAS, Print Server, USB 2.0, RJ45. The all-in-one Solution: Integrated Print Server, NAS and Network USB Hub. Several network users can access one USB device (printer, scanner, hard drive, and so on) LAN port achieves transfer rates of up to 100 Mbps; NAS storage media can be used as.

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

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.

Melec Multifunction Devices Driver

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.

Melec Multifunction Devices DriverDevicesThe 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
KernelAuxiliary bus
KernelDevice drivers/Support APIs
GuestArticlesRybczynska, Marta
Melec multifunction devices driver touchpad
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Summary :

It’s easy to find you need a WIA driver to use this device error on any PCs, for instance, Windows 10, Windows 8 and Windows 7. Once it occurs, your driver scanner will go into trouble and you are not allowed to scan the documents as usual. In order to help Windows users get rid of such scanner driver error, I’d like to introduce the solutions to it.

Melec Multifunction Devices Driver Wireless

Error: You Need a WIA Driver to Use This Device

Windows WIA Scan

The scanners or printers of different brands are used when you try to scan a document. Yet, you may fail to use your scanner on Windows operating systems and see the error:

You need a WIA driver to use this device. Please install it from the installation CD or manufacturer’s website and try again.

You may be able to print normally, but cannot scan sometimes; you may also find it’s impossible to discover the working printer/scanner in devices and printer settings. Don’t be worried too much when you encounter such scanner driver error since it can be solved easily by following methods.

If you’re worrying about the data safety, MiniTool is your good choice.

Before showing you the exact steps to fix you need a WIA driver scanner error, I’d like to tell you the definition of WIA driver.

What Is a WIA Driver

The term WIA stands for Windows Image Acquisition, the proprietary Microsoft driver model and application programming interface. WIA driver refers to the scanner driver. If you receive the You need a WIA driver to use this device error because your scanner won’t scan, please check the WIA service, uninstall or update the driver.

Once you come across the WIA driver missing error, it means that the WIA driver on Windows 10 or other systems gets into trouble; the WIA driver for scanner may become old or fail to be compatible with the system.

You’d better backup your disk in case of any unexpected problems. If accidents really happen and you need to recover lost data from your PC running Windows 10, please read this page:

You are in dire need of a piece of powerful data recovery software for Windows 10 when encountering data loss problems unexpectedly.

How to Fix WIA Driver Error Windows 10

  1. Check WIA service: open Services -> find Windows Image Acquisition (WIA) service -> change its Startup type to Automatic.
  2. Uninstall WIA driver: open Windows Device Manager -> find imaging devices -> right click on your scanner device -> choose Uninstall device.
  3. Update WIA driver manually: go to the official website -> download the latest drivers -> install them on PC.

There are the specific steps to help you fix Windows WIA scan error.

Method 1: check the Windows Image Acquisition (WIA) service.

  1. Right click on the Start button in the lower left corner.
  2. Choose Run from the context menu.
  3. Type services.msc into the text box and hit Enter.
  4. Find Windows Image Acquisition (WIA) from the list and double click on it.
  5. Select Automatic from the drop-down menu after Startup type.
  6. Click Start (if the service is running at present, you may click Stop at first; then, click Start to restart the service).
  7. Click Apply at the bottom right to confirm the changes.

Method 2: uninstall the WIA Driver.

  1. Repeat step 1 mentioned in the previous method.
  2. Choose Device Manager from the menu.
  3. Find Imaging devices from the list and expand it. (If you can't find this item, please try to show it by clicking View tab > selecting Show hidden devices.)
  4. Confirm which your scanner device is and right click on it.
  5. Select Uninstall device option.
  6. Click on the Uninstall button in the prompt window to confirm.
  7. Restart your computer. (The WIA driver download is not needed since Windows will scan all the devices and reinstall the WIA driver for you automatically.)

Method 3: update the WIA driver manually.

  1. Visit the manufacturer’s website of your scanner.
  2. Look for the latest scanner drivers and firmware.
  3. Download them by yourself.
  4. Finish the steps to install the correct scanner drivers and update firmware carefully.

For users who want to finish updating the WIA driver for scanner automatically, they should resort to Driver Booster.

Melec Multifunction Devices Driver Updater

In addition, you can make use of the Troubleshooter in Windows to detect and fix problems autocratically.

Melec Multifunction Devices Driver Scanner

That’s how to fix You need a WIA driver to use this device in different ways easily. If you discover that error on your computer, please remember to follow above methods ASAP!