The bind function is most of the time only called at init time so there
is no need to save a pointer to it in the composite driver structure.
This fixes many section mismatches reported by modpost.
Signed-off-by: Michał Nazarewicz <m.nazarewicz@samsung.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts a commit which proposed an invalid solution
for a section mismatch. Next 3 commits will fix it correctly.
Conflicts:
drivers/usb/gadget/mass_storage.c
Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In may gadgets bind and bind like functions were in a init section
as they were only run during initialisation. However, being
callback functions they were referenced from structures in “normal”
sections. Changing the tag from “__init” to “__ref” fixes the
warnings.
Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The base versions handle constant folding now.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Offer a "how much VBUS power to request" configuration option
for USB gadgets that aren't using board-specific customization
of their gadget or (composite) configuration drivers.
Also remove a couple pointless "depends on USB_GADGET" bits
from the Kconfig text; booleans inside an "if USB_GADGET" will
already have that dependency.
Based on a patch from Justin Clacherty.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Justin Clacherty <justin@redfish-group.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The following patch introduces a new f_obex.c function driver.
It allows userspace obex servers to use usb as transport layer
for their messages.
[ dbrownell@users.sourceforge.net: various fixes and cleanups ]
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change how the serial gadget driver builds: don't use
separate compilation, since it works poorly when key parts
are library code (with init sections etc). Instead be as
close as we can to "gcc --combine ...".
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Bugfix some serial gadget descriptors:
- Stop mangling the low bits (controller type ID) of bcdDevice;
just use the high bits for a driver revision code.
- Serial numbers that aren't specific to individual devices
are useless; stop reporting "0" for this.
- Since it's not part of a CDC-conformant function, the "bulk only"
configuration shouldn't be using "CDC Data" as its interface class.
Switch over to using CLASS_VENDOR_SPEC (different value, 0xff).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Switch serial gadget away from a *very* old idiom: just remember
the endpoints we'll be using, instead of looking them up by name
each time. This is a net code and data (globals) shrink.
Also fix a small memory leak in the rmmod path, by working the
same as the disconnect code.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This removes a needless data structure from the serial gadget code;
it's a small code shrink, and a larger data shrink.
Since "struct usb_request" already has a "struct list_head" reserved
for use by gadget drivers, the serial gadget code doesn't need to
allocate wrapper structs to hold that list ... it can (and should!)
just use the list_head provided for that exact use.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some cleanup/reorg of g_serial ... simplifying it, and disentangling
its structure so morphing it into a "function" driver (combinable with
other interfaces) should be less painful.
- Remove most forward declarations
* put tty and gadget driver structs after their contents
* snug module init/exit decls next to their functions
* reordered some functions
- Other cleanup:
* convert a funky macro to an inline function
* snug up module params next to their declarations
* add missing driver.owner
* add separator lines between major driver sections
- Add comments re potential parameter/#define changes:
* only supports one port (shrank GS_NUM_PORTS)
* changing from 9600-8-N-1 affects multiple sites
- Remove net2280-specific optimization ... it was being done
way too late, can be done by net2280 module options, and in
any case doesn't matter at any sane serial data rates.
There are no behavioral changes, but the macro thing saves I-space.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Based on a patch from <Aurel.Thomi@ruag.com>, this makes the
CDC-ACM support in the serial gadget handle the SET_LINE_CODING
and SET_CONTROL_LINE_STATE requests ... which should improve
interop with at least MS-Windows "usbser.sys" if not some other
ACM host drivers.
It also adds a few REVISIT comments where this code plays a bit
loose with the CDC ACM spec. If this were used to hook up to a
real RS232 or modem link, those places would need a bit of work.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On USB cable disconnect g_serial doesn't hangup the port tty,
which results in an endless read on the tty device. With the
following patch the read and select behave correctly when
the cable is unplugged.
Tested on at91rm9200
Signed-off-by: Savin Zlobec <savin@epiko.si>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We now have pr_err(), pr_warning(), and friends ... start using
them in the gadget stack instead of printk(KERN_ERR) and friends.
This gives us shorter lines and somewhat increased readability.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move <linux/usb_gadget.h> to <linux/usb/gadget.h>, reducing
some of the clutter in the main include directory.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After Serial gadget is being unloaded, neither serial itself, nor other
gadget stuff can be loaded subsequently.
Signed-off-by: Vitaly Bordug <vitb@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Clean up the serial gadget, using newer APIs and conventions:
- gadget_is_dualspeed() and gadget_is_otg() ... #ifdef removal
- Remove many now-needless #includes
- Use the DEBUG and VERBOSE_DEBUG conventions; turned up a bug in
the original debug messaging
- Various whitespace fixes.
This gave only a minor object code shrinkage, but the source looks
much cleaner in various places.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Two of the CDC ACM control requests in the serial gadget have never
been correct, and have been reported to cause serious troubles ... as
in, soft lockup and maybe watchdog reset (depending on hardware).
This patch makes those request fail cleanly, rather than misbehaving.
Someone using CDC ACM should fix them according to the FIXME comments
which now replace the previous bugs.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The USB gadget serial driver uses a semaphore as mutex. Use the
mutex API instead of the (binary) semaphore.
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).
Here is a short excerpt of the semantic patch performing
this transformation:
@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@
x =
- kmalloc
+ kzalloc
(E1,E2)
... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);
@@
expression E1,E2,E3;
@@
- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)
[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a few serial gadget issues reported by the latest "sparse":
some functions should have been defined as static, not just
declared that way.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A SET_LINE_CODING control request should return a zero length packet
as an ACK to the host, during the status phase of a USB transaction.
The return value of gs_setup_class() is treated as the number of
bytes to write in the status phase of the control request, by
gs_setup(). For this case, the value returned by gs_setup_class should
be zero for SET_LINE_CODING but, right now, appears to be
sizeof(struct usb_cdc_line_coding).
However, if after doing the memcpy of the line coding descriptor we
set the variable "ret" to be zero, we should return the appropiate ZLP
to the host as an ACK in the status phase of the control request.
I've tested this out using Linux as both host and slave and confirmed
that the following small change fixes the spurious return of
sizeof(struct usb_cdc_line_coding)/wLength bytes in the status phase
of a USB_CDC_REQ_SET_LINE_CODING request. It's not a huge bug but, it
is worth fixing.
Signed-off-by: Bryan O'Donoghue <bodonoghue@codehermit.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This moves <linux/usb_ch9.h> to <linux/usb/ch9.h> to reduce some of the
clutter of usb header files.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Allow gadget drivers to omit the unbind() method. When they're
statically linked, that's an appropriate memory saving tweak.
Similarly, provide consistent/simpler handling for a should-not-happen
error case: removing a peripheral controller driver when a gadget
driver is still loaded. Such code dates back to early versions of the
first implementation of the gadget API, and has never been triggered.
Includes relevant section annotation fixs for gmidi.c, file_storage.c,
and serial.c; we don't yet have an "init or exit" annotation. Also
some whitespace fixes in gmidi.c (space at EOL, before tabs, etc).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Run this:
#!/bin/sh
for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do
echo "De-casting $f..."
perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f
done
And then go through and reinstate those cases where code is casting pointers
to non-pointers.
And then drop a few hunks which conflicted with outstanding work.
Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Karsten Keil <kkeil@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the grungy swap all the occurrences in the right places patch that
goes with the updates. At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs
If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.
If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)
Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia
[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In some places, particularly drivers and __init code, the init utsns is the
appropriate one to use. This patch replaces those with a the init_utsname
helper.
Changes: Removed several uses of init_utsname(). Hope I picked all the
right ones in net/ipv4/ipconfig.c. These are now changed to
utsname() (the per-process namespace utsname) in the previous
patch (2/7)
[akpm@osdl.org: CIFS fix]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andrey Savochkin <saw@sw.ru>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking. One of these
structures was a struct tty_operations. In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.
This patch declares all struct tty_operations in the tree as const. In all
cases, they are static and used only as input to tty_set_operations. As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.
53 drivers are affected. I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months. serial_core.c was the busiest one that I looked at.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adjust dev->dev_lock spinlock lock/unlock calls to be safe for SMP case.
Otherwise the following sequence may lead to a deadlock in SMP case:
gs_send()->usb_ep_queue()
->(in case a request is satisfied immediatly) gs_write_complete()
for ex for pxa2xx_udc.c:
usb_ep_queue()->pxa2xx_ep_queue()->write_fifo()->done()->gs_write_complete()
(through req.complete pointer)
Signed-off-by: Eugeny S. Mints <emints@ru.mvista.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Recent section changes broke gadget builds on some platforms. This patch
is the best fix that's available until better section markings exist:
- There's a lot of cleanup code that gets used in both init and exit paths;
stop marking it as "__exit".
(Best fix for this would be an "__init_or_exit" section marking, putting
the cleanup in __init when __exit sections get discarded else in __exit.)
- Stop marking the use-once probe routines as "__init" since references
to those routines are not allowed from driver structures. They're now
marked "__devinit", which in practice is a net lose.
(Best fix for this is likely to separate such use-once probe routines
from the driver structure ... but in general, all busses that aren't
hotpluggable will be forced to waste memory for all probe-only code.)
In general these broken section rules waste an average of two to four kBytes
per driver of code bloat ... because none of the relevant code can ever be
reused after module initialization.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I've always found this flag confusing. Now that devfs is no longer around, it
has been renamed, and the documentation for when this flag should be used has
been updated.
Also fixes all drivers that use this flag.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This moves <linux/usb_cdc.h> to <linux/usb/cdc.h> to reduce some of the
clutter of usb header files.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As pointed out by David Brownell, we know that IRQs are never
blocked when calling gs_close function. So the save/restore
IRQ flags are pointless.
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When closing the device, the driver acquires/release twice the
port lock before/after waiting for the data to be completely
sent. Therefore it will dead lock.
This patch fixes it and also uses the generic scheduler services
for waiting for an event.
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
this patch converts drivers/usb to kzalloc usage.
Compile tested with allyes config.
I think there was a bug in drivers/usb/gadget/inode.c because
it used sizeof(*data) for the kmalloc() and sizeof(data) for
the memset(), since sizeof(data) just returns the size for a pointer.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds __init section annotations to gadget driver bind() routines to
remove calls from .text into .init sections (for endpoint autoconfig).
Likewise it adds __exit section annotations to their unbind() routines.
The specification of the gadget driver register/unregister functions is
updated to explicitly allow use of those sections.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
USB gadget drivers make no use of these, remove the pointless
comments.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It looks like that the gs_serial module maybe sleep with spinlock in gs_close.
Sometimes, system hang when I remove the gs_serial module.
From: Fengwei Yin <xaityyy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch centralizes the assignment of bcdDevice numbers for different
gadget controllers. This won't improve the object code at all, but it
does save a lot of repetitive and error-prone source code ... and will
simplify the work of supporting a new controller driver, since most new
gadget drivers will no longer need patches (unless some hardware quirks
limit USB protocol messaging).
Added minor cleanups and identifer hooks for the UDC in the Freescale
iMX series processors.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This updates most of the gadget framework to expect SETUP packets use
USB byteorder (matching the annotation in <linux/usb_ch9.h> and usage
in the host side stack):
- definition in <linux/usb_gadget.h>
- gadget drivers: Ethernet/RNDIS, serial/ACM, file_storage, gadgetfs.
- dummy_hcd
It also includes some other similar changes as suggested by "sparse",
which was used to detect byteorder bugs.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
