running in the EFI boot services environment, to perform data transactions over \r
a USB bus. In addition, it provides an abstraction for the root hub of the USB bus.\r
\r
- Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>\r
+ Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution. The full text of the license may be found at\r
/**\r
Submits isochronous transfer to an isochronous endpoint of a USB device.\r
\r
+ This function is used to submit isochronous transfer to a target endpoint of a USB device. \r
+ The target endpoint is specified by DeviceAddressand EndpointAddress. Isochronous transfers are \r
+ used when working with isochronous date. It provides periodic, continuous communication between \r
+ the host and a device. Isochronous transfers can beused only by full-speed, high-speed, and \r
+ super-speed devices.\r
+\r
+ High-speed isochronous transfers can be performed using multiple data buffers. The number of \r
+ buffers that are actually prepared for the transfer is specified by DataBuffersNumber. For\r
+ full-speed isochronous transfers this value is ignored.\r
+\r
+ Data represents a list of pointers to the data buffers. For full-speed isochronous transfers\r
+ only the data pointed by Data[0]shall be used. For high-speed isochronous transfers and for\r
+ the split transactions depending on DataLengththere several data buffers canbe used. For the\r
+ high-speed isochronous transfers the total number of buffers must not exceed EFI_USB_MAX_ISO_BUFFER_NUM. \r
+\r
+ For split transactions performed on full-speed device by high-speed host controller the total\r
+ number of buffers is limited to EFI_USB_MAX_ISO_BUFFER_NUM1.\r
+ If the isochronous transfer is successful, then EFI_SUCCESSis returned. The isochronous transfer \r
+ is designed to be completed within one USB frame time, if it cannot be completed, EFI_TIMEOUT\r
+ is returned. If an error other than timeout occurs during the USB transfer, then EFI_DEVICE_ERROR\r
+ is returned and the detailed status code will be returned in TransferResult.\r
+\r
+ EFI_INVALID_PARAMETERis returned if one of the following conditionsis satisfied:\r
+ - Data is NULL. \r
+ - DataLength is 0.\r
+ - DeviceSpeed is not one of the supported values listed above.\r
+ - MaximumPacketLength is invalid. MaximumPacketLength must be 1023 or less for full-speed devices,\r
+ and 1024 or less for high-speed and super-speed devices.\r
+ - TransferResult is NULL.\r
+\r
@param This A pointer to the EFI_USB2_HC_PROTOCOL instance.\r
@param DeviceAddress Represents the address of the target device on the USB.\r
@param EndPointAddress The combination of an endpoint number and an endpoint direction of the\r
target USB device.\r
- @param DeviceSpeed Indicates device speed.\r
+ @param DeviceSpeed Indicates device speed. The supported values are EFI_USB_SPEED_FULL, \r
+ EFI_USB_SPEED_HIGH, or EFI_USB_SPEED_SUPER.\r
@param MaximumPacketLength Indicates the maximum packet size the target endpoint is capable of\r
sending or receiving.\r
@param DataBuffersNumber Number of data buffers prepared for the transfer.\r
/**\r
Submits nonblocking isochronous transfer to an isochronous endpoint of a USB device.\r
\r
+ This is an asynchronous type of USB isochronous transfer. If the caller submits a USB\r
+ isochronous transfer request through this function, this function will return immediately.\r
+\r
+ When the isochronous transfer completes, the IsochronousCallbackfunction will be triggered,\r
+ the caller can know the transfer results. If the transfer is successful, the caller can get\r
+ the data received or sent in this callback function.\r
+\r
+ The target endpoint is specified by DeviceAddressand EndpointAddress. Isochronous transfers\r
+ are used when working with isochronous date. It provides periodic, continuous communication\r
+ between the host and a device. Isochronous transfers can be used only by full-speed, high-speed,\r
+ and super-speed devices.\r
+\r
+ High-speed isochronous transfers can be performed using multiple data buffers. The number of \r
+ buffers that are actually prepared for the transfer is specified by DataBuffersNumber. For\r
+ full-speed isochronous transfers this value is ignored.\r
+\r
+ Data represents a list of pointers to the data buffers. For full-speed isochronous transfers\r
+ only the data pointed by Data[0] shall be used. For high-speed isochronous transfers and for\r
+ the split transactions depending on DataLength there several data buffers can be used. For\r
+ the high-speed isochronous transfers the total number of buffers must not exceed EFI_USB_MAX_ISO_BUFFER_NUM.\r
+\r
+ For split transactions performed on full-speed device by high-speed host controller the total\r
+ number of buffers is limited to EFI_USB_MAX_ISO_BUFFER_NUM1.\r
+\r
+ EFI_INVALID_PARAMETER is returned if one of the following conditionsis satisfied:\r
+ - Data is NULL. \r
+ - DataLength is 0.\r
+ - DeviceSpeed is not one of the supported values listed above.\r
+ - MaximumPacketLength is invalid. MaximumPacketLength must be 1023 or less for full-speed \r
+ devices and 1024 or less for high-speed and super-speed devices.\r
+\r
@param This A pointer to the EFI_USB2_HC_PROTOCOL instance.\r
@param DeviceAddress Represents the address of the target device on the USB.\r
@param EndPointAddress The combination of an endpoint number and an endpoint direction of the\r
target USB device.\r
- @param DeviceSpeed Indicates device speed.\r
+ @param DeviceSpeed Indicates device speed. The supported values are EFI_USB_SPEED_FULL, \r
+ EFI_USB_SPEED_HIGH, or EFI_USB_SPEED_SUPER.\r
@param MaximumPacketLength Indicates the maximum packet size the target endpoint is capable of\r
sending or receiving.\r
@param DataBuffersNumber Number of data buffers prepared for the transfer.\r
projects / mirror_edk2.git / blobdiff