tty_port_tty_get may return without any problems NULL. Handle this
case and do not oops in usb_wwan_indat_callback by dereferencing it.

The oops:
Unable to handle kernel paging request for data at address 0x000000d8
Faulting instruction address: 0xc0175b3c
Oops: Kernel access of bad area, sig: 11 [#1]
PowerPC 40x Platform
last sysfs file:
/sys/devices/pci0000:00/0000:00:00.0/0000:01:00.0/0000:02:09.2/usb1/idVendor
Modules linked in:
NIP: c0175b3c LR: c0175e7c CTR: c0215c90
REGS: c77f7d50 TRAP: 0300   Not tainted  (2.6.37-rc5)
MSR: 00021030 <ME,CE,IR,DR>  CR: 88482028  XER: 2000005f
DEAR: 000000d8, ESR: 00000000
TASK = c7141b90[1149] 'wvdial' THREAD: c2750000
GPR00: 00021030 c77f7e00 c7141b90 00000000 0000000e 00000000 0000000e c0410680
GPR08: c683db00 00000000 00000001 c03c81f8 88482028 10073ef4 ffffffb9 ffffff94
GPR16: 00000000 fde036c0 00200200 00100100 00000001 ffffff8d c34fabcc 00000000
GPR24: c71120d4 00000000 00000000 0000000e 00021030 00000000 00000000 0000000e
NIP [c0175b3c] tty_buffer_request_room+0x2c/0x194
LR [c0175e7c] tty_insert_flip_string_fixed_flag+0x3c/0xb0
Call Trace:
[c77f7e00] [00000003] 0x3 (unreliable)
[c77f7e30] [c0175e7c] tty_insert_flip_string_fixed_flag+0x3c/0xb0
[c77f7e60] [c0215df4] usb_wwan_indat_callback+0x164/0x170
...

References: https://bugzilla.kernel.org/show_bug.cgi?id=24582
Cc: Amit Shah <amitshah@gmx.net>
Cc: baoyb <baoyb@avit.org.cn>
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch fixes a build failure[1] by adding the missing uaccess.h needed
for copy_from_user and copy_to_user

References:
	http://kisskb.ellerman.id.au/kisskb/buildresult/3607218/Signed-off-by: NPeter Huewe <peterhuewe@gmx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some devices (ex ZTE 2726) simply don't respond at all when data is sent
to some of their USB interfaces.  The data gets stuck in the TTYs queue
and sits there until close(2), which them blocks because closing_wait
defaults to 30 seconds (even though the fd is O_NONBLOCK).  This is
rarely desired.  Implement the standard mechanism to adjust closing_wait
and let applications handle it how they want to.
Signed-off-by: NDan Williams <dcbw@redhat.com>

Greg prefers this to go through the trivial tree.
http://lkml.org/lkml/2010/6/24/1

There are about 2500 void functions in drivers/usb
Only a few used return; at end of function.

Standardize them a bit.

Moved a statement down a line in drivers/usb/host/u132-hcd.c
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The generic USB serial code is ill-suited for high-speed USB wwan devices,
resulting in the option driver. However, other non-option devices may also
gain similar benefits from not using the generic code. Factorise out the
non-option specific code from the option driver and make it available to
other users.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>