neysx 05/05/03 17:37:35 Modified: xml/htdocs/doc/en usb-guide.xml Log: Improved coding style Added missing $Header$ Used <ul> instead of <p>1)....</p> Split long comments in <pre> No actual content change
Revision Changes Path 1.3 +178 -172 xml/htdocs/doc/en/usb-guide.xml file : http://www.gentoo.org/cgi-bin/viewcvs.cgi/xml/htdocs/doc/en/usb-guide.xml?rev=1.3&content-type=text/x-cvsweb-markup&cvsroot=gentoo plain: http://www.gentoo.org/cgi-bin/viewcvs.cgi/xml/htdocs/doc/en/usb-guide.xml?rev=1.3&content-type=text/plain&cvsroot=gentoo diff : http://www.gentoo.org/cgi-bin/viewcvs.cgi/xml/htdocs/doc/en/usb-guide.xml.diff?r1=1.2&r2=1.3&cvsroot=gentoo Index: usb-guide.xml =================================================================== RCS file: /var/cvsroot/gentoo/xml/htdocs/doc/en/usb-guide.xml,v retrieving revision 1.2 retrieving revision 1.3 diff -u -r1.2 -r1.3 --- usb-guide.xml 14 Apr 2005 10:34:20 -0000 1.2 +++ usb-guide.xml 3 May 2005 17:37:35 -0000 1.3 @@ -1,4 +1,5 @@ <?xml version='1.0' encoding="UTF-8"?> +<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/usb-guide.xml,v 1.3 2005/05/03 17:37:35 neysx Exp $ --> <!DOCTYPE guide SYSTEM "/dtd/guide.dtd"> @@ -18,8 +19,8 @@ <!-- See http://creativecommons.org/licenses/by-sa/2.0 --> <license/> -<version>1.1</version> -<date>2005-04-14</date> +<version>1.2</version> +<date>2005-05-03</date> <chapter> <title>Introduction</title> @@ -28,82 +29,79 @@ <body> <p> -USB stands for Universal Serial Bus and is basically an external interface -standard that enables communication between the computer and various other -peripherals. Some of the most commonly used USB devices today are keyboards, -mice, pen drives, digital cameras, external CD & DVD writers, printers etc. +USB stands for Universal Serial Bus and is basically an external interface +standard that enables communication between the computer and various other +peripherals. Some of the most commonly used USB devices today are keyboards, +mice, pen drives, digital cameras, external CD & DVD writers, printers etc. </p> <p> -There are currently two versions of USB in use, i.e. USB 1.1 and USB 2.0. -Since USB has always been backward compatible with its previous versions, -USB 2.0 is backwards compatible with USB 1.1. The latest USB devices are -typically USB 2.0 compatible. USB 2.0 supports a maximum data transmission -speed of 480 Mbps or 60 MBps and this is the major difference between the two -standards. Another advantage with USB is that the devices are all -<e>hot-pluggable</e>, which means that you do not have to restart your system +There are currently two versions of USB in use, i.e. USB 1.1 and USB 2.0. +Since USB has always been backward compatible with its previous versions, +USB 2.0 is backwards compatible with USB 1.1. The latest USB devices are +typically USB 2.0 compatible. USB 2.0 supports a maximum data transmission +speed of 480 Mbps or 60 MBps and this is the major difference between the two +standards. Another advantage with USB is that the devices are all +<e>hot-pluggable</e>, which means that you do not have to restart your system in order for you to be able to use these devices. </p> </body> </section> - <section> <title>A Technical Perspective</title> <body> <p> -Before we go onto the exact configuration options in the kernel, it would -be apt to look at USB in a little more detail. If you're in a hurry or want +Before we go onto the exact configuration options in the kernel, it would +be apt to look at USB in a little more detail. If you're in a hurry or want to skip this section, please go to <uri link="#kernel">Kernel Configuration</uri>. </p> <p> -A USB system has a host controller, hubs, a <e>root hub</e> amongst others -and can support up to 127 USB devices including the hubs. The host controller -is nothing but the hardware interface between the USB device and the -operating system. There are a couple of HCI (Host Controller Interface) -in use today and they are the OHCI (Open HCI) by Compaq, UHCI (Universal HCI) -and EHCI (Enhanced HCI), both from Intel. The OHCI/UHCI are the two industry +A USB system has a host controller, hubs, a <e>root hub</e> amongst others +and can support up to 127 USB devices including the hubs. The host controller +is nothing but the hardware interface between the USB device and the +operating system. There are a couple of HCI (Host Controller Interface) +in use today and they are the OHCI (Open HCI) by Compaq, UHCI (Universal HCI) +and EHCI (Enhanced HCI), both from Intel. The OHCI/UHCI are the two industry standard USB 1.1 interfaces whereas the EHCI is for USB 2.0. </p> <p> -The hardware vendor provides an interface for the programmer that allows -the system to interact with the hardware and this is called the HCD or Host -Controller Device. It is through this HCD that the device interacts with the +The hardware vendor provides an interface for the programmer that allows +the system to interact with the hardware and this is called the HCD or Host +Controller Device. It is through this HCD that the device interacts with the system software. The following diagram should make things easier to comprehend. </p> <pre caption="General USB Architecture"> -<comment>(Software consists of other components as well like the device driver, but - for the sake of simplicity, they are not shown)</comment> +<comment>(Software consists of other components as well like the device driver, but +for the sake of simplicity, they are not shown)</comment> - + ---- Hardware ---- + ---- Software ---- + + + ---- Hardware ---- + ---- Software ---- + | | | - | [USB Dev] -+-> {EHCI} -+---> ( EHCD ) | + | [USB Dev] -+-> {EHCI} -+---> ( EHCD ) | | | | | User | `-> {UHCI} -+---> ( UHCD ) | | | | + ---- Hardware ---- + ---- Software ---- + - </pre> - + <p> -A USB device can either use a custom driver or use one already present in -the system and this is based on the concept of a device <e>class</e>. This -means that if a device belongs to a certain <e>class</e>, then other devices -belonging to the same <e>class</e> can make use of the same device driver. -Some of these <e>classes</e> are the USB HID (Human Interface Devices) class -which covers input devices like keyboards and mice, the USB Mass Storage -devices class which covers devices like pen drives, digital cameras, audio -players etc and the USB CDC (Communication Devices Class) which essentially +A USB device can either use a custom driver or use one already present in +the system and this is based on the concept of a device <e>class</e>. This +means that if a device belongs to a certain <e>class</e>, then other devices +belonging to the same <e>class</e> can make use of the same device driver. +Some of these <e>classes</e> are the USB HID (Human Interface Devices) class +which covers input devices like keyboards and mice, the USB Mass Storage +devices class which covers devices like pen drives, digital cameras, audio +players etc and the USB CDC (Communication Devices Class) which essentially covers USB modems and similar devices. </p> </body> </section> - <section id="#lspci"> <title>What's on your machine?</title> <body> @@ -114,8 +112,8 @@ </p> <note> -The <c>lspci</c> tool is a part of the <c>sys-apps/pciutils</c> package. If -you do not have this installed, please <c>emerge pciutils</c>. Please note +The <c>lspci</c> tool is a part of the <c>sys-apps/pciutils</c> package. If +you do not have this installed, please <c>emerge pciutils</c>. Please note that you have to be root while running the <c>lspci</c> command. </note> @@ -134,8 +132,8 @@ </pre> <p> -So using the <c>lspci</c> command, we can find out if the system supports -USB 2.0. This is useful as we will be enabling the corresponding options in +So using the <c>lspci</c> command, we can find out if the system supports +USB 2.0. This is useful as we will be enabling the corresponding options in the kernel. </p> @@ -150,20 +148,21 @@ <body> <note> -Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless -you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a -2.6 kernel on <e>most</e> architectures. Please check your kernel version and +Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless +you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a +2.6 kernel on <e>most</e> architectures. Please check your kernel version and then proceed with the configuration accordingly. </note> <p> -First emerge the kernel sources of your choice. Here we'll use the -<c>gentoo-sources</c> For more information on the various kernel sources available on Portage, -please look up the <uri link="/doc/en/gentoo-kernel.xml">Gentoo Linux Kernel Guide</uri>. +First emerge the kernel sources of your choice. Here we'll use the +<c>gentoo-sources</c> For more information on the various kernel sources +available on Portage, please look up the <uri +link="/doc/en/gentoo-kernel.xml">Gentoo Linux Kernel Guide</uri>. </p> <pre caption="Getting the kernel sources"> -# <i> emerge gentoo-sources</i> +# <i>emerge gentoo-sources</i> </pre> <p> @@ -171,38 +170,37 @@ </p> <pre caption="Heading over to the source"> -# <i> cd /usr/src/linux</i> <<Truncated>> -- [email protected] mailing list
