kernel_optimize_test/drivers/usb
David Brownell c1dca562be usb gadget: split out serial core
This abstracts the "gadget serial" driver TTY glue into a separate
component, cleaning it up and disentangling it from connection state.

It also changed some behaviors for the better:

  - Stops using "experimental" major #127, and switches over to
    having the TTY layer allocate the dev_t numbers.
    
  - Provides /sys/class/tty/ttyGS* nodes, thus mdev/udev support.
    (Note "mdev" hotplug bug in Busybox v1.7.2: /dev/ttyGS0 will
    be a *block* device without CONFIG_SYSFS_DEPRECATED_V2.)

  - The tty nodes no longer reject opens when there's no host.
    Now they can support normal getty configs in /etc/inttab...

  - Now implements RX throttling.  When the line discipline says
    it doesn't want any more data, only packets in flight will be
    delivered (currently, max 1K/8K at full/high speeds) until it
    unthrottles the data.

  - Supports low_latency.  This is a good policy for all USB serial
    adapters, since it eliminates scheduler overhead on RX paths.

This also includes much cleanup including better comments, fixing
memory leaks and other bugs (including some locking fixes), messaging
cleanup, and an interface audit and tightening.  This added up to a
significant object code shrinkage, on the order of 20% (!) depending
on CPU and compiler.

A separate patch actually kicks in this new code, using the functions
declared in this new header, and removes the previous glue.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:15:59 -07:00
..
atm cxacru: treat firmware data as const 2008-07-10 14:26:14 +01:00
c67x00 usb/c67x00 endianness annotations 2008-06-04 08:06:01 -07:00
class USB: fix cdc-acm resume() 2008-07-03 18:20:36 -07:00
core USB: remove CVS keywords 2008-07-21 15:15:55 -07:00
gadget usb gadget: split out serial core 2008-07-21 15:15:59 -07:00
host USB: isp1760-hcd.c: make 2 functions static 2008-07-21 15:15:54 -07:00
image usb: replace remaining __PRETTY_FUNCTION__ occurrences 2008-04-24 21:16:48 -07:00
misc USB: remove CVS keywords 2008-07-21 15:15:55 -07:00
mon USB Monitor: BKL pushdown 2008-06-20 14:05:53 -06:00
serial USB: remove CVS keywords 2008-07-21 15:15:55 -07:00
storage USB: remove CVS keywords 2008-07-21 15:15:55 -07:00
Kconfig USB: add support for SuperH OHCI 2008-02-01 14:35:03 -08:00
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

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.