1 files changed, 44 insertions, 54 deletions

diff --git a/Documentation/DocBook/usb.tmpl b/Documentation/DocBook/usb.tmpl
index 320af25de3a2..8a28f76b9359 100644
--- a/Documentation/DocBook/usb.tmpl
+++ b/Documentation/DocBook/usb.tmpl
@@ -43,59 +43,52 @@
 
     <para>A Universal Serial Bus (USB) is used to connect a host,
     such as a PC or workstation, to a number of peripheral
-    devices.  USB uses a tree structure, with the host at the
+    devices.  USB uses a tree structure, with the host as the
     root (the system's master), hubs as interior nodes, and
-    peripheral devices as leaves (and slaves).
+    peripherals as leaves (and slaves).
     Modern PCs support several such trees of USB devices, usually
     one USB 2.0 tree (480 Mbit/sec each) with
     a few USB 1.1 trees (12 Mbit/sec each) that are used when you
     connect a USB 1.1 device directly to the machine's "root hub".
     </para>
 
-    <para>That master/slave asymmetry was designed in part for
-    ease of use.  It is not physically possible to assemble
-    (legal) USB cables incorrectly:  all upstream "to-the-host"
-    connectors are the rectangular type, matching the sockets on
-    root hubs, and the downstream type are the squarish type
-    (or they are built in to the peripheral).
-    Software doesn't need to deal with distributed autoconfiguration
-    since the pre-designated master node manages all that.
-    At the electrical level, bus protocol overhead is reduced by
-    eliminating arbitration and moving scheduling into host software.
+    <para>That master/slave asymmetry was designed-in for a number of
+    reasons, one being ease of use.  It is not physically possible to
+    assemble (legal) USB cables incorrectly:  all upstream "to the host"
+    connectors are the rectangular type (matching the sockets on
+    root hubs), and all downstream connectors are the squarish type
+    (or they are built into the peripheral).
+    Also, the host software doesn't need to deal with distributed
+    auto-configuration since the pre-designated master node manages all that.
+    And finally, at the electrical level, bus protocol overhead is reduced by
+    eliminating arbitration and moving scheduling into the host software.
     </para>
 
-    <para>USB 1.0 was announced in January 1996, and was revised
+    <para>USB 1.0 was announced in January 1996 and was revised
     as USB 1.1 (with improvements in hub specification and
     support for interrupt-out transfers) in September 1998.
-    USB 2.0 was released in April 2000, including high speed
-    transfers and transaction translating hubs (used for USB 1.1
+    USB 2.0 was released in April 2000, adding high-speed
+    transfers and transaction-translating hubs (used for USB 1.1
     and 1.0 backward compatibility).
     </para>
 
-    <para>USB support was added to Linux early in the 2.2 kernel series
-    shortly before the 2.3 development forked off.  Updates
-    from 2.3 were regularly folded back into 2.2 releases, bringing
-    new features such as <filename>/sbin/hotplug</filename> support,
-    more drivers, and more robustness.
-    The 2.5 kernel series continued such improvements, and also
-    worked on USB 2.0 support,
-    higher performance,
-    better consistency between host controller drivers,
-    API simplification (to make bugs less likely),
-    and providing internal "kerneldoc" documentation.
+    <para>Kernel developers added USB support to Linux early in the 2.2 kernel
+    series, shortly before 2.3 development forked.  Updates from 2.3 were
+    regularly folded back into 2.2 releases, which improved reliability and
+    brought <filename>/sbin/hotplug</filename> support as well more drivers.
+    Such improvements were continued in the 2.5 kernel series, where they added
+    USB 2.0 support, improved performance, and made the host controller drivers
+    (HCDs) more consistent.  They also simplified the API (to make bugs less
+    likely) and added internal "kerneldoc" documentation.
     </para>
 
     <para>Linux can run inside USB devices as well as on
     the hosts that control the devices.
-    Because the Linux 2.x USB support evolved to support mass market
-    platforms such as Apple Macintosh or PC-compatible systems,
-    it didn't address design concerns for those types of USB systems.
-    So it can't be used inside mass-market PDAs, or other peripherals.
-    USB device drivers running inside those Linux peripherals
+    But USB device drivers running inside those peripherals
     don't do the same things as the ones running inside hosts,
-    and so they've been given a different name:
-    they're called <emphasis>gadget drivers</emphasis>.
-    This document does not present gadget drivers.
+    so they've been given a different name:
+    <emphasis>gadget drivers</emphasis>.
+    This document does not cover gadget drivers.
     </para>
 
     </chapter>
@@ -103,17 +96,14 @@
 <chapter id="host">
     <title>USB Host-Side API Model</title>
 
-    <para>Within the kernel,
-    host-side drivers for USB devices talk to the "usbcore" APIs.
-    There are two types of public "usbcore" APIs, targetted at two different
-    layers of USB driver.  Those are
-    <emphasis>general purpose</emphasis> drivers, exposed through
-    driver frameworks such as block, character, or network devices;
-    and drivers that are <emphasis>part of the core</emphasis>,
-    which are involved in managing a USB bus.
-    Such core drivers include the <emphasis>hub</emphasis> driver,
-    which manages trees of USB devices, and several different kinds
-    of <emphasis>host controller driver (HCD)</emphasis>,
+    <para>Host-side drivers for USB devices talk to the "usbcore" APIs.
+    There are two.  One is intended for
+    <emphasis>general-purpose</emphasis> drivers (exposed through
+    driver frameworks), and the other is for drivers that are
+    <emphasis>part of the core</emphasis>.
+    Such core drivers include the <emphasis>hub</emphasis> driver
+    (which manages trees of USB devices) and several different kinds
+    of <emphasis>host controller drivers</emphasis>,
     which control individual busses.
     </para>
 
@@ -122,21 +112,21 @@
      
     <itemizedlist>
 
-        <listitem><para>USB supports four kinds of data transfer
-        (control, bulk, interrupt, and isochronous).  Two transfer
-        types use bandwidth as it's available (control and bulk),
-        while the other two types of transfer (interrupt and isochronous)
+        <listitem><para>USB supports four kinds of data transfers
+        (control, bulk, interrupt, and isochronous).  Two of them (control
+        and bulk) use bandwidth as it's available,
+        while the other two (interrupt and isochronous)
         are scheduled to provide guaranteed bandwidth.
         </para></listitem>
 
         <listitem><para>The device description model includes one or more
         "configurations" per device, only one of which is active at a time.
-        Devices that are capable of high speed operation must also support
-        full speed configurations, along with a way to ask about the
-        "other speed" configurations that might be used.
+        Devices that are capable of high-speed operation must also support
+        full-speed configurations, along with a way to ask about the
+        "other speed" configurations which might be used.
         </para></listitem>
 
-        <listitem><para>Configurations have one or more "interface", each
+        <listitem><para>Configurations have one or more "interfaces", each
         of which may have "alternate settings".  Interfaces may be
         standardized by USB "Class" specifications, or may be specific to
         a vendor or device.</para>
@@ -162,7 +152,7 @@
         </para></listitem>
 
         <listitem><para>The Linux USB API supports synchronous calls for
-        control and bulk messaging.
+        control and bulk messages.
         It also supports asynchnous calls for all kinds of data transfer,
         using request structures called "URBs" (USB Request Blocks).
         </para></listitem>