This driver is only for one device id, and the option driver should be
used instead for it.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Acked-by: NPete Zaitcev <zaitcev@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

mark this array as const because it is read-only
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Mark the tables as const so that they end up in .rodata
section and don't cacheline share with things that get
written to.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Cc: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1102) clarifies two points in the USB Gadget kerneldoc:

	Request completion callbacks are always made with interrupts
	disabled;

	Device controllers may not support STALLing the status stage
	of a control transfer after the data stage is over.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

General cleanup on ir-usb module. Introduced
a common header that could be used also on
usb gadget framework.

Lot's of cleanups and now using macros from the header
file.
Signed-off-by: NFelipe Balbi <me@felipebalbi.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch fixes some performance bugs observed with some workloads
when unlinking EHCI queue header (QH) descriptors from the async ring
(control/bulk schedule).

The mechanism intended to defer unlinking an empty QH (so there is no
penalty in common cases where it's quickly reused) was not working as
intended.  Sometimes the unlink was scheduled:

 - too quickly ... which can be a *strong* negative effect, since
   that QH becomes unavailable for immediate re-use;

 - too slowly ... wasting DMA cycles, usually a minor issue except
   for increased bus contention and power usage;

Plus there was an extreme case of "too slowly":  a logical error in the
IAA watchdog-timer conversion meant that sometimes the unlink never
got scheduled.

The fix replaces a simple counter with a timestamp derived from the
controller's 8 KHz microframe counter, and adjusts the timer usage
for some issues associated with HZ being less than 8K.

(Based on a patch originally by Alan Stern, and good troubleshooting
from  Leonid.)
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Leonid <leonidv11@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We can't allow hubs on the 7th tier as they would allow
devices on the 8th tier.
Signed-off-by: NFelipe Balbi <felipe.balbi@nokia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If we do rmmod ohci_hcd while an application is doing something, the
following may happen:

- a control URB completes (in finish_urb) and the ohci's endpoint is
  set into ED_UNLINK in ed_deschedule
- same URB is (re)submitted because of the open/close loop or other
  such application behaviour
- rmmod sets the state to HC_STATE_QUESCING
- finish_unlinks happens at next SOF; normally it would set ed into
  ED_IDLE and immediately call ed_schedule (since URB had extra TDs
  queued), which sets it into ED_OPER. But the check in ed_schedule
  makes it fail with -EAGAIN (which is ignored)
- from now on we have a dead URB stuck; it cannot even be unlinked
  because the ed status is not ED_OPER, and thus start_ed_unlink is
  not invoked.

This patch removes the check. In 2.6.25, all callers check for
__ACTIVE bit before invoking ed_schedule, which is more appropriate.

Alan Stern and David Brownell approved of this (cautiously).
Signed-off-by: NPete Zaitcev <zaitcev@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

As RMK pointed out,  considering the fact that the _only_ platform with
a PXA and SA1111 is the Lubbock, and that SA1111 DMA doesn't work there,
(i.e. the SA1111 OHCI doesn't work there) the SA1111 OHCI driver should
really be made SA11x0 specific.
Signed-off-by: NEric Miao <eric.miao@marvell.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Looks like usb_put_hcd was missing. Also, make an always-zero function
return void.
Signed-off-by: NPete Zaitcev <zaitcev@yahoo.com>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

i is used only as a for-loop index no need to declare another.
drivers/usb/atm/speedtch.c:832:7: warning: symbol 'i' shadows an earlier one
drivers/usb/atm/speedtch.c:766:6: originally declared here
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The get/set 2101_config helpers take an unsigned int rather than an
int.  It is safe to change these in each case and may even produce
better code as it will be an unsigned divide rather than a signed
divide in places.  All other manipulation was setting/masking bits
which will not be affected by the sign change.

Fixes the following sparse warnings:
drivers/usb/serial/cp2101.c:378:44: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:378:44:    expected unsigned int *data
drivers/usb/serial/cp2101.c:378:44:    got int *<noident>
drivers/usb/serial/cp2101.c:388:40: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:388:40:    expected unsigned int *data
drivers/usb/serial/cp2101.c:388:40:    got int *<noident>
drivers/usb/serial/cp2101.c:413:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:413:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:413:42:    got int *<noident>
drivers/usb/serial/cp2101.c:421:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:421:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:421:42:    got int *<noident>
drivers/usb/serial/cp2101.c:444:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:444:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:444:42:    got int *<noident>
drivers/usb/serial/cp2101.c:451:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:451:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:451:42:    got int *<noident>
drivers/usb/serial/cp2101.c:458:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:458:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:458:42:    got int *<noident>
drivers/usb/serial/cp2101.c:471:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:471:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:471:42:    got int *<noident>
drivers/usb/serial/cp2101.c:481:42: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:481:42:    expected unsigned int *data
drivers/usb/serial/cp2101.c:481:42:    got int *<noident>
drivers/usb/serial/cp2101.c:561:41: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:561:41:    expected unsigned int *data
drivers/usb/serial/cp2101.c:561:41:    got int *<noident>
drivers/usb/serial/cp2101.c:591:45: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:591:45:    expected unsigned int *data
drivers/usb/serial/cp2101.c:591:45:    got int *<noident>
drivers/usb/serial/cp2101.c:597:41: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:597:41:    expected unsigned int *data
drivers/usb/serial/cp2101.c:597:41:    got int *<noident>
drivers/usb/serial/cp2101.c:608:45: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:608:45:    expected unsigned int *data
drivers/usb/serial/cp2101.c:608:45:    got int *<noident>
drivers/usb/serial/cp2101.c:614:41: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:614:41:    expected unsigned int *data
drivers/usb/serial/cp2101.c:614:41:    got int *<noident>
drivers/usb/serial/cp2101.c:623:45: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:623:45:    expected unsigned int *data
drivers/usb/serial/cp2101.c:623:45:    got int *<noident>
drivers/usb/serial/cp2101.c:680:50: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:680:50:    expected unsigned int *data
drivers/usb/serial/cp2101.c:680:50:    got int *<noident>
drivers/usb/serial/cp2101.c:690:43: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:690:43:    expected unsigned int *data
drivers/usb/serial/cp2101.c:690:43:    got int *<noident>
drivers/usb/serial/cp2101.c:715:41: warning: incorrect type in argument 3 (different signedness)
drivers/usb/serial/cp2101.c:715:41:    expected unsigned int *data
drivers/usb/serial/cp2101.c:715:41:    got int *<noident>
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is another case where the lock_kernel appears to be unneccessary and
could be removed with a bit more investigative work
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The BKL is actually probably not needed as the mutex seems sufficient. If
so then a further patch to drop it would be a good followup.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Also fix the unknown ioctl return code
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

I'm pretty sure the mutex is sufficient for all locking but will come
back to that later if the USB folks don't beat me to it. For now get rid
of the old BKL ioctl method and wrap the ioctl handler
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

I'm pretty sure this can be eliminated however I couldn't prove (or find)
what stopped the device vanishing mid IOCTL_GET_HARD_VERSION. Perhaps a
USB wizard could double check that and see if the lock_kernel can go
entirely.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

ftdi has one ioctl, which is buggy and for debugging. Kill it off
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This keeps the gadget ioctl method wrapped but pushes the BKL down into
the gadget code so we can use unlocked_ioctl().
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Building on the previous patches which took code from this driver and
pakaged it in more-reusable network "function" components, this patch
gets rid of the original code and uses those components instead.

As seen with the other gadget driver conversions, the resulting code
is much easier to understand and (presumably) work with.  In this case
that's especially true, since the Ethernet gadget had grown to handle
three (!) different Ethernet-over-USB protocols.  This modularization
should make it much easier to add a fourth option for the newish CDC
"Ethernet Emulation Model" (or EEM).

Lightly tested, primarily at full speed.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is a simple example of a composite gadget, combining two
Communications Class Device (CDC) functions:  ECM and ACM.

This provides a clear example of how the composite gadget framework
is intended to work.  It's surprising that MS-Windows (or at least,
XP and previous) won't "just work" with something this simple...

One /proc/bus/usb/devices listing looks like:

  T:  Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 46 Spd=480 MxCh= 0
  D:  Ver= 2.00 Cls=02(comm.) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
  P:  Vendor=0525 ProdID=a4aa Rev= 3.01
  S:  Manufacturer=Linux 2.6.26-rc6-pnut with net2280
  S:  Product=CDC Composite Gadget
  C:* #Ifs= 4 Cfg#= 1 Atr=c0 MxPwr=  2mA
  I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=cdc_ether
  E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=32ms
  I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether
  I:* If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether
  E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  I:* If#= 2 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=cdc_acm
  E:  Ad=86(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
  I:* If#= 3 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_acm
  E:  Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  E:  Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

Not all USB peripheral controller hardware can support this driver.
All the highspeed-capable peripheral controllers with drivers now in
the mainline kernel seem to support this, as does omap_udc.  But
many full speed controllers don't have enough endpoints, or (as with
the PXA controllers) don't support altsettings.

Lightly tested.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is a RNDIS function driver, extracted from the all-in-one
Ethernet gadget driver.

Lightly tested ... there seems to be a pre-existing problem when
talking to Windows XP SP2, not quite sure what's up with that yet.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is a "CDC Ethernet" (ECM) function driver, extracted from the
all-in-one Ethernet gadget driver.

This is a good example of how to implement interface altsettings.
In fact it's currently the only such example in the gadget stack,
pending addition of OBEX support.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is a simple "CDC Subset" (and MCCI "SAFE") function driver, extracted
from the all-in-one Ethernet gadget driver.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Abstract the peripheral side Ethernet-over-USB link layer code from
the all-in-one Ethernet gadget driver into a component that can be
called by various functions, so the various flavors can be split
apart and selectively reused.

A notable difference from the approach taken with the serial link
layer code (beyond talking to NET not TTY) is that because of the
initialization requirements, this only supports one network link.
(And one set of Ethernet link addresses.)

That is, each configuration may have only one instance of a network
function.  This doesn't change behavior; the current code has that
same restriction.  If you want multiple logical links, that can
easily be done using network layer tools.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some cleanup to the RNDIS code:

 - Minor bugfix:  rndis_unit() is supposed to put the link into the
   RNDIS_UNINITIALIZED state, which does not mean "unused".  There's
   a separate method to stop using the link.  (Bug doesn't affect
   anything right now because of how the code is used.)

 - Reduce coupling between RNDIS code and its user(s), in preparation
   for updates in that code:

    * Decouple RNDIS_RESPONSE_AVAILABLE notifications from net_device
      by passing just a void* handle.  (Also, remove the unused return
      value of the notification callback.)
    * When it needs a copy of net_device stats, just ask for it

 - Remove unused/untested code backing various never-used OIDs:

    * RNDIS_PM, RNDIS_WAKEUP ... "should" get implemented, but the
      relevant docs were unclear, ambguous, and incomplete.  Someone
      with access to the Hidden Gospels (maybe in the EU?) might be
      able to figure out what this should do.
    * RNDIS_OPTIONAL_STATS ... as the name suggests, optional.  Never
      implemented in part because not all the semantics were clear.
    * OID_GEN_RNDIS_CONFIG_PARAMETER, which has been #if 0 forever.

 - A few small whitespace fixes

Plus switch the VERBOSE symbol over to the newer VERBOSE_DEBUG style.

There should be no functional changes because of this patch; it's a
net source code shrink (because of the dead/unused code removal) and
a small object code shrink (a couple hundred bytes on ARMv5).
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This switches the serial gadget over to using the new "function"
versions of the serial port interfacing code.  The remaining code
in the main source file is quite small...
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Split out the generic serial support into a "function driver".  This
closely mimics the ACM support, but with a MUCH simpler control model.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Split out CDC ACM parts of "gadget serial" to a "function driver".
Some key structural differences from the previous ACM support, shared
with with the generic serial function (next patch):

 - As a function driver, it can be combined with other functions.
   One gadget configuration could offer both serial and network
   links, as an example.

 - One serial port can be exposed in multiple configurations;
   the /dev/ttyGS0 node could be exposed regardless of which
   config the host selected.

 - One configuration can expose multiple serial ports, such as
   ttyGS0, ttyGS1, ttyGS2, and ttyGS3.

This code should be a lot easier to understand than the previous
all-in-one-big-file version of the driver.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Update Gadget Zero to use the more modular versions of the loopback
and source/sink configuration drivers which build on the new gadget
framework code.

The core code is a LOT simpler, and it should be much easier now to
understand how the parts fit together.  The conversion is an overall
source shrink in terms of this gadget, since it uses more midlayer
support.  However, it's an overall increase in object size because
there's less sharing between the two configurations (improves code
clarity) and because the midlayer is a bit more functional than this
driver actually needs.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This splits the gadget zero "loopback" configuration into a standalone
"configuration driver", building on the composite gadget framework code.
It doesn't yet pull the original code out of gadget zero or update how
that driver is built.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This splits the gadget zero "source/sink" configuration into a standalone
"configuration driver", building on the composite gadget framework code.
It doesn't yet pull the original code out of gadget zero or update how
that driver is built.

Neither this, nor its sibling "loopback" configuration, is a function
driver that can be combined with other functions.  (The host "usbtest"
driver wouldn't know how to deal with that!)  However the code becomes
simpler because of this conversion, so it's a net win.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add <linux/usb/composite.h> interfaces for composite gadget drivers, and
basic implementation support behind it:

  - struct usb_function ... groups one or more interfaces into a function
    managed as one unit within a configuration, to which it's added by
    usb_add_function().

  - struct usb_configuration ... groups one or more such functions into
    a configuration managed as one unit by a driver, to which it's added
    by usb_add_config().  These operate at either high or full/low speeds
    and at a given bMaxPower.

  - struct usb_composite_driver ... groups one or more such configurations
    into a gadget driver, which may be registered or unregistered.

  - struct usb_composite_dev ... a usb_composite_driver manages this; it
    wraps the usb_gadget exposed by the controller driver.

This also includes some basic kerneldoc.

How to use it (the short version):  provide a usb_composite_driver with a
bind() that calls usb_add_config() for each of the needed configurations.
The configurations in turn have bind() calls, which will usb_add_function()
for each function required.  Each function's bind() allocates resources
needed to perform its tasks, like endpoints; sometimes configurations will
allocate resources too.

Separate patches will convert most gadget drivers to this infrastructure.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Define three new descriptor manipulation utilities, for use when
setting up functions that may have multiple instances:

	usb_copy_descriptors() to copy a vector of descriptors
	usb_free_descriptors() to free the copy
	usb_find_endpoint() to find a copied version

These will be used as follows.  Functions will continue to have static
tables of descriptors they update, now used as __initdata templates.

When a function creates a new instance, it patches those tables with
relevant interface and string IDs, plus endpoint assignments.  Then it
copies those morphed descriptors, associates the copies with the new
function instance, and records the endpoint descriptors to use when
activating the endpoints.  When initialization is done, only the copies
remain in memory.  The copies are freed on driver removal.

This ensures that each instance has descriptors which hold the right
instance-specific data.  Two instances in the same configuration will
obviously never share the same interface IDs or use the same endpoints.
Instances in different configurations won't do so either, which means
this is slightly less memory-efficient in some cases.

This also includes a bugfix to the epautoconf code that shows up with
this usage model.  It must replace the previous endpoint number when
updating the template descriptors, not just mask in a few more bits.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Teach "gadget serial" to use the new abstracted (and bugfixed) TTY glue,
and remove all the orignal tangled-up code.  Update the documentation
accordingly.  This is a net object code shrink and cleanup; it should
make it a lot easier to see how the TTY glue should accomodate updates
to the TTY layer, be bugfixed, etc.

Notable behavior changes include:  it can now support getty even when
there's no USB connection; it fits properly into the mdev/udev world;
and RX handling is better (throttling works, and low latency).

Configurations with scripts setting up the /dev/ttygserial device node
(with "experimental" major number) may want to change that to be a
symlink pointing to the /dev/ttyGS0 file, as a migration aid; else,
just switch entirely over to mdev/udev.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

It turns out newer versions of the AT91 UDC hardware have increased
sizes of some of the FIFOs.  Reporting that is a Good Thing.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>