Template:USBIntroductionPage

Description

This template have USB introduction and Acronyms & definitions.

Parameters

This template takes 1 parameter

• The Mnemonic that specifies SoC type. The existing Mnemnoics are
  • DM8148/DM813X/DM811X
  • AM335X

Example

To use this template simply add the following line to your wiki page. Change the mnemonic according to the desired SoC. This example is for the AM335x SoC.

{{USBIntroductionPage|TI811x}}

Here's how it will look in your wiki page:

Introduction

The TI811x USBSS consists of two instance of mentor usb controller (musb controller). Each controller supports USB2.0 standards supporting HS/FS/LS speed. Each musb controller uses CPPI4.1 (Communication programming port interface 4.1 compliance) based DMA controller to transfer of data to/from between the external memory and endpoint FIFO. There are 15 Tx/Rx endpoints for each controller and each Tx/Rx endpoint uses dedicated Tx/Rx CPPI4.1 DMA channel for transfer of data. The endpoint-0 used for control transfer. For more information please refer to Technical reference manual at here

References

• The USB2.0 specification standard at USB 2.0 spec
• Refer corresponding TI811x Technical Reference Manual at here
• Refer approved usb class specification documents here

Acronyms & Definitions

USB Driver: Acronyms

Acronym	Definition
USB	Universal Serial Bus
OTG	On The Go
HS/FS/LS	Highspeed/Fullspeed/LowSpeed
UAC	USB Audio Class
UVC	USB Video Class
HID	Human Interface Devices
CDC	Communication Device Class
RNDIS	Remote Network Device Interface Specification
DTM	Driver Test Manager
CPPI	Communication programming port interface
USBSS	USB subsystem

Software Architecture

Mentor graphics usb otg controller driver (or MUSB driver)

The MUSB driver is implemented on top of Mentor controller IP which supports all the speeds (High, Full and Low). TI811x USBOTG subsytem uses CPPI 4.1 DMA for all the transfers. The musb driver confirms to linux usb framework support both in PIO/DMA mode of operation. The musb host controller driver (HCD) binds the controller hardware and linux usb core stack. The musb device/gadget controller driver binds the controller hardware and specific gadget driver (filestorage, cdc/rndis etc).

Linux USB Stack Architecture

As shown in the figure, linux usb stack is an layered architecture, musb controller being the lowest layer, the musb host/device controller driver binds the musb controller hardware to linux usb stack frame work. The CPPI4.1 DMA controller driver is responsible for transmission/reception of packets over the musb endpoints.

Features

• The Mentor USB driver can be built as module or built-in to kernel
• Support both PIO and DMA mode (The DMA mode not applicable for control endpoint)
• Support two instances musb controller in host mode (both usb0 and usb1 controller in host mode).
• Support USB gadget/device mode only (In this gadget only mode, only USB0 controller can be configured as Gadget and USB1 cannot be configured as gadget mode)
• Dual role support : Concurrent usage of one port as USB host and other port as USB device (refer USB Userguide for details)