linux/drivers/usb
Enrico Scholz 3f02a957d5 usb: ISP1760: improve pre-fetch timing
ISP1760 requires a delay of 90ns between programming the address and
reading the data.  Current driver solves this by a mdelay(1) which is
very heavy weighted and slow.  This patch applies the workaround from
the ISP1760 FAQ by using two different banks for PTD and payload data
and using a common wait for them.  This wait is done by an additional
ISP1760 access (whose timing constraints guarantee the 90ns delay).
This improves speed when reading from an USB stick from:

  $ time dd if=/dev/sda of=/dev/zero bs=65536 count=1638
  real    1m 15.43s
  user    0m 0.44s
  sys     0m 39.46s

to

  $ time dd if=/dev/sda of=/dev/zero bs=65536 count=1638
  real    0m 18.53s
  user    0m 0.16s
  sys     0m 12.97s

[bigeasy@linutronix.de: fixed comment formating, moved define into
   header file, obey 80 char rule]

Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-13 17:32:53 -07:00
..
atm USB: cxacru: Fix printk format flag in error message 2008-08-13 17:32:52 -07:00
c67x00 usb/c67x00 endianness annotations 2008-06-04 08:06:01 -07:00
class tty: rework break handling 2008-07-22 13:03:28 -07:00
core USB: fix interface unregistration logic 2008-08-13 17:32:50 -07:00
gadget USB: serial gadget: rx path data loss fixes 2008-08-13 17:32:53 -07:00
host usb: ISP1760: improve pre-fetch timing 2008-08-13 17:32:53 -07:00
image usb: replace remaining __PRETTY_FUNCTION__ occurrences 2008-04-24 21:16:48 -07:00
misc usb: auerswald: remove driver (obsolete) 2008-08-13 17:32:47 -07:00
mon SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
serial USB Serial Sierra: TRU-Install feature update 2008-08-13 17:32:51 -07:00
storage USB: usb-storage Motorola Phone Razr v3xx US_FL_FIX_CAPACITY patch 2008-08-13 17:32:52 -07:00
Kconfig USB: Move usb/mon/ up to misc options in Kconfig 2008-08-13 17:32:50 -07:00
Makefile USB: add Cypress c67x00 OTG controller HCD driver 2008-05-02 10:25:57 -07:00
README USB: fix directory references in usb/README 2007-11-28 13:58:34 -08:00
usb-skeleton.c USB: remove unnecessary type casting of urb->context 2008-04-24 21:16:55 -07:00

README

To understand all the Linux-USB framework, you'll use these resources:

    * This source code.  This is necessarily an evolving work, and
      includes kerneldoc that should help you get a current overview.
      ("make pdfdocs", and then look at "usb.pdf" for host side and
      "gadget.pdf" for peripheral side.)  Also, Documentation/usb has
      more information.

    * The USB 2.0 specification (from www.usb.org), with supplements
      such as those for USB OTG and the various device classes.
      The USB specification has a good overview chapter, and USB
      peripherals conform to the widely known "Chapter 9".

    * Chip specifications for USB controllers.  Examples include
      host controllers (on PCs, servers, and more); peripheral
      controllers (in devices with Linux firmware, like printers or
      cell phones); and hard-wired peripherals like Ethernet adapters.

    * Specifications for other protocols implemented by USB peripheral
      functions.  Some are vendor-specific; others are vendor-neutral
      but just standardized outside of the www.usb.org team.

Here is a list of what each subdirectory here is, and what is contained in
them.

core/		- This is for the core USB host code, including the
		  usbfs files and the hub class driver ("khubd").

host/		- This is for USB host controller drivers.  This
		  includes UHCI, OHCI, EHCI, and others that might
		  be used with more specialized "embedded" systems.

gadget/		- This is for USB peripheral controller drivers and
		  the various gadget drivers which talk to them.


Individual USB driver directories.  A new driver should be added to the
first subdirectory in the list below that it fits into.

image/		- This is for still image drivers, like scanners or
		  digital cameras.
../input/	- This is for any driver that uses the input subsystem,
		  like keyboard, mice, touchscreens, tablets, etc.
../media/	- This is for multimedia drivers, like video cameras,
		  radios, and any other drivers that talk to the v4l
		  subsystem.
../net/		- This is for network drivers.
serial/		- This is for USB to serial drivers.
storage/	- This is for USB mass-storage drivers.
class/		- This is for all USB device drivers that do not fit
		  into any of the above categories, and work for a range
		  of USB Class specified devices. 
misc/		- This is for all USB device drivers that do not fit
		  into any of the above categories.