For more info about the Surface MSI naming convention, see Deploy the latest firmware and drivers for Surface devices. If there's not an.msi file that corresponds to the build of Windows 10 you have installed, select the.msi file that's closest to (but still lower than) your build number. The output of lsusb -v will reveal that the device has a subsystem ID of: 0fe9:d501 Making it work Firmware. It requires the firmware file: dvb-usb-bluebird-01.fw Drivers. The following drivers are needed for this device: - lgdt330x.ko - dvb-usb.ko - dvb-usb-cxusb.ko External Links. DViCO product page. Input Output Audio Driver Controller is an application designed to help you view the input and output drivers of the sound cards you have installed on your computer. Since you can check both types. USB Driver Updates. Need USB Driver Downloads for Windows 10, Windows 8, Windows 7, Vista and XP?If you are having problems with your USB not working, read the article below to help fix your USB problems.USB issues often, but not always, relate to drivers problems.

Starting with Windows 10, release 1703, a USB Audio 2.0 driver is shipped with Windows. It is designed to support the USB Audio 2.0 device class. The driver is a WaveRT audio port class miniport. For more information about the USB Audio 2.0 device class, see https://www.usb.org/documents?search=&type%5B0%5D=55&items_per_page=50.

In Internet Explorer, click Tools, and then click Internet Options. On the Security tab, click the Trusted Sites icon. Click Sites and then add these website addresses one at a time to the list: You can only add one address at a time and you must click Add after each one.

The driver is named: usbaudio2.sys and the associated inf file is usbaudio2.inf.

The driver will identify in device manager as 'USB Audio Class 2 Device'. This name will be overwritten with a USB Product string, if it is available.

The driver is automatically enabled when a compatible device is attached to the system. However, if a third-party driver exists on the system or Windows Update, that driver will be installed and override the class driver.

Architecture

usbaudio2.sys fits within the wider architecture of Windows USB Audio as shown.

Related USB specifications

The following USB specifications define USB Audio and are referenced in this topic.

• USB-2 refers to the Universal Serial Bus Specification, Revision 2.0
• ADC-2 refers to the USB Device Class Definition for Audio Devices, Release 2.0.
• FMT-2 refers to the Audio Data Formats specification, Release 2.0.

The USB-IF is a special interest group that maintains the Official USB Specification, test specifications and tools.

Audio formats

The driver supports the formats listed below. An alternate setting which specifies another format defined in FMT-2, or an unknown format, will be ignored.

Type I formats (FMT-2 2.3.1):

• PCM Format with 8..32 bits per sample (FMT-2 2.3.1.7.1)
• PCM8 Format (FMT-2 2.3.1.7.2)
• IEEE_FLOAT Format (FMT-2 2.3.1.7.3)

Type III formats (FMT-2 2.3.3 and A.2.3):

• IEC61937_AC-3
• IEC61937_MPEG-2_AAC_ADTS
• IEC61937_DTS-I
• IEC61937_DTS-II
• IEC61937_DTS-III
• TYPE_III_WMA

Feature descriptions

This section describes the features of the USB Audio 2.0 driver.

Audio function topology

The driver supports all entity types defined in ADC-2 3.13.

Each Terminal Entity must have a valid clock connection in compatible USB Audio 2.0 hardware. The clock path may optionally include Clock Multiplier and Clock Selector units and must end in a Clock Source Entity.

The driver supports one single clock source only. If a device implements multiple clock source entities and a clock selector, then the driver will use the clock source that is selected by default and will not modify the clock selector’s position.

A Processing Unit (ADC-2 3.13.9) with more than one input pin is not supported.

An Extension Unit (ADC-2 3.13.10) with more than one input pin is not supported.

Cyclic paths in the topology are not allowed.

Audio streaming

The driver supports the following endpoint synchronization types (USB-2 5.12.4.1):

• Asynchronous IN and OUT
• Synchronous IN and OUT
• Adaptive IN and OUT

For the asynchronous OUT case the driver supports explicit feedback only. A feedback endpoint must be implemented in the respective alternate setting of the AS interface. The driver does not support implicit feedback.

There is currently limited support for devices using a shared clock for multiple endpoints.

For the Adaptive IN case the driver does not support a feedforward endpoint. If such an endpoint is present in the alternate setting, it will be ignored. The driver handles the Adaptive IN stream in the same way as an Asynchronous IN stream.

The size of isochronous packets created by the device must be within the limits specified in FMT-2.0 section 2.3.1.1. This means that the deviation of actual packet size from nominal size must not exceed +/- one audio slot (audio slot = channel count samples).

Descriptors

An audio function must implement exactly one AudioControl Interface Descriptor (ADC-2 4.7) and one or more AudioStreaming Interface Descriptors (ADC-2 4.9). A function with an audio control interface but no streaming interface is not supported.

The driver supports all descriptor types defined in ADC-2, section 4. The following subsections provide comments on some specific descriptor types.

Class-Specific AS interface descriptor

For details on this specification, refer to ADC-2 4.9.2.

An AS interface descriptor must start with alternate setting zero with no endpoint (no bandwidth consumption) and further alternate settings must be specified in ascending order in compatible USB Audio 2.0 hardware.

An alternate setting with a format that is not supported by the driver will be ignored.

Each non-zero alternate setting must specify an isochronous data endpoint, and optionally a feedback endpoint. A non-zero alternate setting without any endpoint is not supported.

The bTerminalLink field must refer to a Terminal Entity in the topology and its value must be identical in all alternate settings of an AS interface.

The bFormatType field in the AS interface descriptor must be identical to bFormatType specified in the Format Type Descriptor (FMT-2 2.3.1.6).

For Type I formats, exactly one bit must be set to one in the bmFormats field of the AS interface descriptor. Otherwise, the format will be ignored by the driver.

To save bus bandwidth, one AS interface can implement multiple alternate settings with the same format (in terms of bNrChannels and AS Format Type Descriptor) but different wMaxPacketSize values in the isochronous data endpoint descriptor. For a given sample rate, the driver selects the alternate setting with the smallest wMaxPacketSize that can fulfill the data rate requirements.

Type I format type descriptor

For details on this specification, refer to FMT-2 2.3.1.6.

The following restrictions apply:

Class-Specific AS isochronous audio data endpoint descriptor

For details on this specification, refer to ADC-2 4.10.1.2.

The MaxPacketsOnly flag in the bmAttributes field is not supported and will be ignored.

The fields bmControls, bLockDelayUnits and wLockDelay will be ignored.

Class requests and interrupt data messages

The driver supports a subset of the control requests defined in ADC-2, section 5.2, and supports interrupt data messages (ADC-2 6.1) for some controls. The following table shows the subset that is implemented in the driver.

Drivers Dvico Input Devices

Additional information on the controls and requests is available in the following subsections.

Clock source entity

For details on this specification, refer to ADC-2 5.2.5.1.

At a minimum, a Clock Source Entity must implement Sampling Frequency Control GET RANGE and GET CUR requests (ADC-2 5.2.5.1.1) in compatible USB Audio 2.0 hardware.

The Sampling Frequency Control GET RANGE request returns a list of subranges (ADC-2 5.2.1). Each subrange describes a discrete frequency, or a frequency range. A discrete sampling frequency must be expressed by setting MIN and MAX fields to the respective frequency and RES to zero. Individual subranges must not overlap. If a subrange overlaps a previous one, it will be ignored by the driver.

A Clock Source Entity which implements one single fixed frequency only does not need to implement Sampling Frequency Control SET CUR. It implements GET CUR which returns the fixed frequency, and it implements GET RANGE which reports one single discrete frequency.

Clock selector entity

For details on this specification, refer to ADC-2 5.2.5.2

The USB Audio 2.0 driver does not support clock selection. The driver uses the Clock Source Entity which is selected by default and never issues a Clock Selector Control SET CUR request. The Clock Selector Control GET CUR request (ADC-2 5.2.5.2.1) must be implemented in compatible USB Audio 2.0 hardware.

Feature unit

For details on this specification, refer to ADC-2 5.2.5.7.

The driver supports one single volume range only. If the Volume Control GET RANGE request returns more than one range, then subsequent ranges will be ignored.

The volume interval expressed by the MIN and MAX fields should be an integer multiple of the step size specified in the RES field.

If a feature unit implements single channel controls as well as a master control for Mute or Volume, then the driver uses the single channel controls and ignores the master control.

Additional Information for OEM and IHVs

OEMs and IHVs should test their existing and new devices against the supplied in-box driver.

There is not any specific partner customization that is associated with the in-box USB Audio 2.0 driver.

This INF file entry (provided in a update to Windows Release 1703), is used to identify that the in-box driver is a generic device driver.

The in-box driver registers for the following compatible IDs with usbaudio2.inf.

See the USB audio 2.0 specification for subclass types.

USB Audio 2.0 Devices with MIDI (subclass 0x03 above) will enumerate the MIDI function as a separate multi-function device with usbaudio.sys (USB Audio 1.0 driver) loaded.

The USB Audio 1.0 class driver registers this compatible ID with wdma_usb.inf.

And has these exclusions:

An arbitrary number of channels (greater than eight) are not supported in shared mode due to a limitation of the Windows audio stack.

IHV USB Audio 2.0 drivers and updates

For IHV provided third party driver USB Audio 2.0 drivers, those drivers will continue to be preferred for their devices over our in-box driver unless they update their driver to explicitly override this behavior and use the in-box driver.

Audio Jack Registry Descriptions

Starting in Windows 10 release 1703, IHVs that create USB Audio Class 2.0 devices having one or more jacks have the capability to describe these jacks to the in-box Audio Class 2.0 driver. The in-box driver uses the supplied jack information when handling the KSPROPERTY_JACK_DESCRIPTION for this device.

Jack information is stored in the registry in the device instance key (HW key).

The following describes the audio jack information settings in the registry:

<tid> = terminal ID (As defined in the descriptor)

<n> = Jack number (1 ~ n).

Convention for <tid> and <n> is:

• Base 10 (8, 9, 10 rather than 8, 9, a)
• No leading zeros
• n is 1-based (first jack is jack 1 rather than jack 0)

For example:

T1_NrJacks, T1_J2_ChannelMapping, T1_J2_ConnectorType

For additional audio jack information, see KSJACK_DESCRIPTION structure.

These registry values can be set in various ways:

• By using custom INFs which wrap the in-box INF for the purpose to set these values.

• Directly by the h/w device via a Microsoft OS Descriptors for USB devices (see example below). For more information about creating these descriptors, see Microsoft OS Descriptors for USB Devices.

Microsoft OS Descriptors for USB Example

The following Microsoft OS Descriptors for USB example contains the channel mapping and color for one jack. The example is for a non-composite device with single feature descriptor.

The IHV vendor should extend it to contain any other information for the jack description.

Troubleshooting

If the driver does not start, the system event log should be checked. The driver logs events which indicate the reason for the failure. Similarly, audio logs can be manually collected following the steps described in this blog entry. If the failure may indicate a driver problem, please report it using the Feedback Hub described below, and include the logs.

For information on how to read logs for the USB Audio 2.0 class driver using supplemental TMF files, see this blog entry. For general information on working with TMF files, see Displaying a Trace Log with a TMF File.

For information on 'Audio services not responding' error and USB audio device does not work in Windows 10 version 1703 see, USB Audio Not Playing

Feedback Hub

If you run into a problem with this driver, collect audio logs and then follow steps outlined in this blog entry to bring it to our attention via the Feedback Hub.

Driver development

This USB Audio 2.0 class driver was developed by Thesycon and is supported by Microsoft.

See also

1.1. The simplest example¶

Here comes a very simple example of an input device driver. The device hasjust one button and the button is accessible at i/o port BUTTON_PORT. Whenpressed or released a BUTTON_IRQ happens. The driver could look like:

1.2. What the example does¶

First it has to include the <linux/input.h> file, which interfaces to theinput subsystem. This provides all the definitions needed.

In the _init function, which is called either upon module load or whenbooting the kernel, it grabs the required resources (it should also checkfor the presence of the device).

Then it allocates a new input device structure with input_allocate_device()and sets up input bitfields. This way the device driver tells the otherparts of the input systems what it is - what events can be generated oraccepted by this input device. Our example device can only generate EV_KEYtype events, and from those only BTN_0 event code. Thus we only set thesetwo bits. We could have used:

Drivers Dvico Input Devices Definition

as well, but with more than single bits the first approach tends to beshorter.

Then the example driver registers the input device structure by calling:

This adds the button_dev structure to linked lists of the input driver andcalls device handler modules _connect functions to tell them a new inputdevice has appeared. input_register_device() may sleep and therefore mustnot be called from an interrupt or with a spinlock held.

While in use, the only used function of the driver is:

which upon every interrupt from the button checks its state and reports itvia the:

call to the input system. There is no need to check whether the interruptroutine isn’t reporting two same value events (press, press for example) tothe input system, because the input_report_* functions check thatthemselves.

Then there is the:

call to tell those who receive the events that we’ve sent a complete report.This doesn’t seem important in the one button case, but is quite importantfor for example mouse movement, where you don’t want the X and Y valuesto be interpreted separately, because that’d result in a different movement.

1.3. dev->open() and dev->close()¶

In case the driver has to repeatedly poll the device, because it doesn’thave an interrupt coming from it and the polling is too expensive to be doneall the time, or if the device uses a valuable resource (eg. interrupt), itcan use the open and close callback to know when it can stop polling orrelease the interrupt and when it must resume polling or grab the interruptagain. To do that, we would add this to our example driver:

Note that input core keeps track of number of users for the device andmakes sure that dev->open() is called only when the first user connectsto the device and that dev->close() is called when the very last userdisconnects. Calls to both callbacks are serialized.

The open() callback should return a 0 in case of success or any nonzero valuein case of failure. The close() callback (which is void) must always succeed.

1.4. Basic event types¶

The most simple event type is EV_KEY, which is used for keys and buttons.It’s reported to the input system via:

See uapi/linux/input-event-codes.h for the allowable values of code (from 0 toKEY_MAX). Value is interpreted as a truth value, ie any nonzero value means keypressed, zero value means key released. The input code generates events onlyin case the value is different from before.

In addition to EV_KEY, there are two more basic event types: EV_REL andEV_ABS. They are used for relative and absolute values supplied by thedevice. A relative value may be for example a mouse movement in the X axis.The mouse reports it as a relative difference from the last position,because it doesn’t have any absolute coordinate system to work in. Absoluteevents are namely for joysticks and digitizers - devices that do work in anabsolute coordinate systems.

Having the device report EV_REL buttons is as simple as with EV_KEY, simplyset the corresponding bits and call the:

function. Events are generated only for nonzero value.

However EV_ABS requires a little special care. Before callinginput_register_device, you have to fill additional fields in the input_devstruct for each absolute axis your device has. If our button device had alsothe ABS_X axis:

Or, you can just say:

This setting would be appropriate for a joystick X axis, with the minimum of0, maximum of 255 (which the joystick must be able to reach, no problem ifit sometimes reports more, but it must be able to always reach the min andmax values), with noise in the data up to +- 4, and with a center flatposition of size 8.

If you don’t need absfuzz and absflat, you can set them to zero, which meanthat the thing is precise and always returns to exactly the center position(if it has any).

1.5. BITS_TO_LONGS(), BIT_WORD(), BIT_MASK()¶

These three macros from bitops.h help some bitfield computations:

1.6. The id* and name fields¶

The dev->name should be set before registering the input device by the inputdevice driver. It’s a string like ‘Generic button device’ containing auser friendly name of the device.

The id* fields contain the bus ID (PCI, USB, ...), vendor ID and device IDof the device. The bus IDs are defined in input.h. The vendor and device idsare defined in pci_ids.h, usb_ids.h and similar include files. These fieldsshould be set by the input device driver before registering it.

The idtype field can be used for specific information for the input devicedriver.

The id and name fields can be passed to userland via the evdev interface.

1.7. The keycode, keycodemax, keycodesize fields¶

These three fields should be used by input devices that have dense keymaps.The keycode is an array used to map from scancodes to input system keycodes.The keycode max should contain the size of the array and keycodesize thesize of each entry in it (in bytes).

Userspace can query and alter current scancode to keycode mappings usingEVIOCGKEYCODE and EVIOCSKEYCODE ioctls on corresponding evdev interface.When a device has all 3 aforementioned fields filled in, the driver mayrely on kernel’s default implementation of setting and querying keycodemappings.

1.8. dev->getkeycode() and dev->setkeycode()¶

getkeycode() and setkeycode() callbacks allow drivers to override defaultkeycode/keycodesize/keycodemax mapping mechanism provided by input coreand implement sparse keycode maps.

1.9. Key autorepeat¶

... is simple. It is handled by the input.c module. Hardware autorepeat isnot used, because it’s not present in many devices and even where it ispresent, it is broken sometimes (at keyboards: Toshiba notebooks). To enableautorepeat for your device, just set EV_REP in dev->evbit. All will behandled by the input system.

1.10. Other event types, handling output events¶

The other event types up to now are:

• EV_LED - used for the keyboard LEDs.
• EV_SND - used for keyboard beeps.

They are very similar to for example key events, but they go in the otherdirection - from the system to the input device driver. If your input devicedriver can handle these events, it has to set the respective bits in evbit,and also the callback routine:

This callback routine can be called from an interrupt or a BH (although thatisn’t a rule), and thus must not sleep, and must not take too long to finish.