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Core modules, Host stack, Device stack – Philips ISP1362 User Manual

Page 7

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Philips Semiconductors

ISP1362 Linux Stack User’s Guide

UM10012-_2

© Koninklijke Philips Electronics N.V. 2003. All rights reserved.

User’s Guide

Rev. 1.2—July 2003

7 of 34

2.3. Core

Modules

2.3.1. Host

Stack

The host stack consists of the Host Controller Driver (HCD) module. The driver is used for data transfer on the
USB bus for the connected devices. This driver can work in parallel with other HCDs

(OHCI HCD, UHCI HCD,

EHCI HCD)

present in the kernel. This is a kernel module and the Linux OS has support for USB, connected USB

device class drivers and suitable applications.

Figure 2-1: ISP1362 Linux Stack Architecture

2.3.2. Device

Stack

The device stack consists of the Device Controller Driver (DCD), the USB protocol driver, and the mass storage
class driver. The DCD is responsible for data transfer over the USB bus. The USB protocol driver responds to the
standard USB protocol requests. The mass storage class driver adds the mass storage functionality to the USB
device, and responds to the mass storage class commands and protocol. The mass storage needs to interface with
the physical mass storage device to perform its operations, and the physical disk is customer platform-specific and

ISP1362 Hardware Access Layer Driver

Mass Storage bridge

Mass Storage disk

emulation

OTG Mass storage demo/

OTG tools

Linux File System

Linux operating system

Linux kernel

ISP1362 Hardware

Mass Storage class driver

USB protocol driver

Device Controller Driver

USB core

USB class drivers

basic device drivers

OTG driver

Host Controller Driver

ISP1362 stack core modules

ISP1362 application modules

Linux kernel drivers

ISP1362 porting modules