1
Commit Graph

51 Commits

Author SHA1 Message Date
Alan Stern
4d2fae8b35 USB: cypress_m8: remove invalid Clear-Halt
This patch (as1265) removes an erroneous call to usb_clear_halt from
the cypress_m8 driver.  The call isn't valid because it is made from
interrupt context whereas usb_clear_halt is a blocking routine.

Presumably the code has never been executed; if it did it would cause
an oops.  So instead treat -EPIPE like any other sort of unexplained
error.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-07-12 15:16:40 -07:00
Alan Stern
f9c99bb8b3 USB: usb-serial: replace shutdown with disconnect, release
This patch (as1254) splits up the shutdown method of usb_serial_driver
into a disconnect and a release method.

The problem is that the usb-serial core was calling shutdown during
disconnect handling, but drivers didn't expect it to be called until
after all the open file references had been closed.  The result was an
oops when the close method tried to use memory that had been
deallocated by shutdown.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:47 -07:00
Alan Cox
335f8514f2 tty: Bring the usb tty port structure into more use
This allows us to clean stuff up, but is probably also going to cause
some app breakage with buggy apps as we now implement proper POSIX behaviour
for USB ports matching all the other ports. This does also mean other apps
that break on USB will now work properly.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11 08:50:56 -07:00
Oliver Neukum
2400a2bfbd USB: removal of tty->low_latency hack dating back to the old serial code
This removes tty->low_latency from all USB serial drivers that push
data into the tty layer at hard interrupt context. It's no longer needed
and actually harmful.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-23 14:15:29 -07:00
Greg Kroah-Hartman
194343d936 USB: remove use of err() in drivers/usb/serial
err() is going away, so switch to dev_err() or printk() if it's really
needed.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:41:10 -07:00
Greg Kroah-Hartman
c197a8db59 USB: remove info() macro from usb/serial drivers
USB should not be having it's own printk macros, so remove info() and
use the system-wide standard of dev_info() wherever possible.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:41:09 -07:00
Alan Cox
4a90f09b20 tty: usb-serial krefs
Use kref in the USB serial drivers so that we don't free tty structures
from under the URB receive handlers as has historically been the case if
you were unlucky. This also gives us a framework for general tty drivers to
use tty_port objects and refcount.

Contains two err->dev_err changes merged together to fix clashes in the
-next tree.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 09:51:41 -07:00
Alan Cox
77336828c0 usb-cypress: There is no 0 case to go with CS5/6/7/8 so remove the test
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 13:03:23 -07:00
Alan Cox
813a224fa5 cypress_m8: coding style
Coding style clean ups

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 13:03:23 -07:00
Alan Cox
95da310e66 usb_serial: API all change
USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 13:03:22 -07:00
Al Viro
fd05e72009 drivers/usb annotations and fixes
* endianness annotations
* endianness fixes
* missing get_unaligned/put_unaligned

It's pretty much all over the place, changes to different files are independent.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Serial-parts-Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 10:03:31 -07:00
Ming Lei
cdc9779228 USB: remove unnecessary type casting of urb->context
urb->context code cleanup

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:55 -07:00
Harvey Harrison
441b62c1ed USB: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:55 -07:00
Greg Kroah-Hartman
0ba4034e20 USB: serial: remove unneeded number endpoints settings
The usb-serial core no longer checks these fields so remove them from
all of the individual drivers.  They will be removed from the usb-serial
core in a patch later in the series.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:52 -07:00
Alan Cox
8873aaa6e5 USB: cypress_m8: Speed handling
The recent changes to this driver cleaned it up a lot, follow that up
by sorting the speed side of things out as well

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:41 -07:00
Mike Isely
92983c2121 USB: cypress_m8: Limit baud rate to <=4800 for USB low speed devices
The cypress app note for the M8 states that for the USB low speed
version of the part, throughput is effectively limited to 800
bytes/sec.  So if we were to try a faster baud rate in such cases then
we risk overrun errors on receive.  Best to just identify this case
and limit the rate to 4800 baud or less (by ignoring any request to
set a faster rate).  The old baud rate setting code was somewhat
fragile; this change also hopefully makes it easier in the future to
better checking / limiting.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:38 -07:00
Mike Isely
6768306c3d USB: cypress_m8: Get rid of pointless NULL check
Remove a NULL check in cypress_m8; the check is useless in this
context because it is referenced earlier in the same code path thus
the kernel would be oops'ed before reaching this point anyway.  (And
it's really pointless here anyway; if this pointer somehow is NULL the
driver is going to have serious problems in many other places.)

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:37 -07:00
Mike Isely
3d6aa32065 USB: cypress_m8: Don't issue GET_CONFIG for certain devices
Earthmate LT-20 devices (both "old" and "new" versions) can't tolerate
a GET_CONFIG command.  The original Earthmate has no trouble with
this.  Presumably other non-Earthmate devices are still OK as well.
This change disables the use of GET_CONFIG for cases where it is known
not to work.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:37 -07:00
Mike Isely
3416eaa1f8 USB: cypress_m8: Packet format is separate from characteristic size
cypress_m8: Packet format is separate from characteristic size

The Cypress app note states that when using an 8 byte packet buffer
size that the packet format is modified (to be more compact).  However
I have since discovered that newer DeLorme Earthmate LT-20 devices
(those that are low speed USB with 8 byte packet size) STILL use the
format that is really supposed to correspond to 32 byte packets.
Further confusing things is the subsequent discovery that there are
actually two different types of LT-20 - older LT-20's use 32 byte
packets which is probably why this issue wasn't originally
encountered.  The solution here is to flag the packet format
separately from the buffer size.  Then at initialization time,
identify the correct combination and set it up.  This is a critical
fix for anyone with a newer LT-20.  Older devices and non-Earthmate
devices should remain unaffected by this change.  (If other devices
behave in this, uh, unexpected manner, it's now just a simple 1 line
change to fix them as well (change the pkt_fmt member for that
device).  Default behavior with this patch is still to drive the
format as per the app-note; of course for Earthmate devices this is
overridden.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:37 -07:00
Mike Isely
93075544d6 USB: cypress_m8: Feature buffer fixes
cypress_m8: Feature buffer fixes

From: Mike Isely <isely@pobox.com>

Don't hardcode the feature buffer size; use sizeof() instead.  That
way we can easily specify the size in a single spot.  Speaking of the
feature buffer size, the Cypress app note (and further testing with a
DeLorme Earthmate) suggests that this size should be 5 not 8 bytes.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:36 -07:00
Dmitry Shapin
6f6f06ee6a USB: cypress_m8: add UPS Powercom (0d9f:0002)
Add support for UPS Powercom USB interface (0d9f:0002) in chip CY7C63723.
In my case, this Powercom BNT800AP.

Signed-off-by: Dmitry Shapin <shapin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-10 16:42:25 -07:00
Oliver Neukum
9e3b1d8e3d USB: stop abuse of intfdata in cypress_m8
this driver uses usb_get_intfdata() == NULL as a test for disconnect().
You must not do that as this races with probe(). By the time you test
your erstwhile interface may already be somebody else's interface.
This fixes the close() method of cypress_m8 to use the recently introduced
flag and use locking against disconnect() where required in close().

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 14:35:04 -08:00
Greg Kroah-Hartman
8d7bc55ecf USB: serial: cypress_m8: clean up urb->status usage
This done in anticipation of removal of urb->status, which will make
that patch easier to review and apply in the future.


Cc: <linux-usb-devel@lists.sourceforge.net>
Cc: Lonnie Mendez <dignome@gmail.com>
Cc: Neil Whelchel <koyama@firstlight.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-12 16:34:32 -07:00
Johannes Hölzl
d9b1b78773 USB serial: add driver pointer to all usb-serial drivers
Every usb serial driver should have a pointer to the corresponding usb driver.
So the usb serial core can add a new id not only to the usb serial driver, but
also to the usb driver.

Also the usb drivers of ark3116, mos7720 and mos7840 missed the flag
no_dynamic_id=1. This is added now.

Signed-off-by: Johannes Hölzl <johannes.hoelzl@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 15:44:34 -08:00
Alan
b1cff285ae usb serial: Eliminate bogus ioctl code
Several drivers have bogus ioctl code that tries unneccessarily to
override the standard processing. In the three cases here the actual code
is not only wrong but also not required as they implement the proper
set_termios method as well.

Remove the junk.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:13:23 -08:00
Robert P. J. Day
5cbded585d [PATCH] getting rid of all casts of k[cmz]alloc() calls
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>
2006-12-13 09:05:58 -08:00
Alan Cox
606d099cdd [PATCH] tty: switch to ktermios
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>
2006-12-08 08:28:57 -08:00
Mariusz Kozlowski
2e46b74852 usb: cypress_m8 init error path fix
If at some point cypress_init() fails deregister
only the resources that were registered until that point.

Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:23:37 -08:00
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Mike Isely
78aef519ed cypress_m8: implement graceful failure handling
When receiving a fatal error from the USB core, e.g. EILSEQ (which can
happen if the polling interval is too short), fail gracefully.
Previously the driver would fill the log with useless error messages
or (more alarmingly) silently spin forever trying to write updated
control information to the device.  This change implements a new flag
which if cleared indicates that the driver has failed.  The flag will
be set on initialization, cleared on fatal errors, and anything else
that touches the USB port in the driver will abort if the flag is
clear.  When the flag is cleared, a message will be logged indicating
that the driver has failed.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:59 -07:00
Mike Isely
48298e50e0 cypress_m8: improve control endpoint error handling
Fix usb core function error return checks to look for negative errno
values, not positive errno values.  This bug had rendered those checks
useless.  Also remove attempted error recovery on control endpoints
for EPIPE - with control endpoints EPIPE does not indicate a halted
endpoint so trying to recover with usb_clear_halt() is not the correct
action.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:58 -07:00
Mike Isely
9aa8dae7b1 cypress_m8: use usb_fill_int_urb where appropriate
Rather than directly filling in URB fields, it's safer to use
usb_fill_int_urb().  This improves robustness of the driver; URB
changes in the future will not go uninitialized here.  That point not
withstanding, this driver should at least be self-consistent.  Either
use usb_fill_int_urb() everywhere or don't bother with it all.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:58 -07:00
Mike Isely
0257fa9ffe cypress_m8: use appropriate URB polling interval
The polling interval for the device can't always be 1msec.  If it is
too quick, the device can fail causing a fatal (to the driver) EILSEQ
error from the USB core.  The actual correct value is reported by the
device as part of its configuration data, so use that value as the
default.  On a DeLorme Earthmate for example, the device reports that
it wants a 6msec interval.  As part of this fix, the "interval" module
option has been fixed as well; the device's default can be overridden
by specifying interval=<value> as a module option.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:58 -07:00
Greg Kroah-Hartman
a969888ce9 [PATCH] USB: move usb-serial.h to include/linux/usb/
USB serial outside of the kernel tree can not build properly due to
usb-serial.h being buried down in the source tree.  This patch moves the
location of the file to include/linux/usb and fixes up all of the usb
serial drivers to handle the move properly.

Cc: Sergei Organov <osv@javad.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-12 16:03:25 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Pete Zaitcev
cf2c7481d2 [PATCH] USB serial: encapsulate schedule_work, remove double-calling
I'm going to throw schedule_work away, it's retarded. But for starters,
let's have it encapsulated.

Also, generic and whiteheat were both calling usb_serial_port_softint
and scheduled work. Only one was necessary.

Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-21 15:04:13 -07:00
Lonnie Mendez
a5c44e29e5 [PATCH] USB: cypress_m8: add support for the Nokia ca42-version 2 cable
This patch adds support for the Nokia ca42 version 2 cable to the
cypress_m8 driver.  The device was tested by others with this patch and
found to be compatible with the cypress_m8 driver.  A special note
should be taken that this cable seems to vary in the type of chipset
used.  This patch supports the cable with product id 0x4101.

Signed-off-by: Lonnie Mendez <lmendez19@austin.rr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 14:50:00 -08:00
Eric Sesterhenn
80b6ca4832 [PATCH] USB: kzalloc() conversion for rest of drivers/usb
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 14:49:59 -08:00
Alan Cox
33f0f88f1c [PATCH] TTY layer buffering revamp
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>
2006-01-10 08:01:59 -08:00
Adrian Bunk
943ffb587c spelling: s/retreive/retrieve/
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-10 00:10:13 +01:00
Greg Kroah-Hartman
ba9dc657af [PATCH] USB: allow usb drivers to disable dynamic ids
This lets drivers, like the usb-serial ones, disable the ability to add
ids from sysfs.

The usb-serial drivers are "odd" in that they are really usb-serial bus
drivers, not usb bus drivers, so the dynamic id logic will have to go
into the usb-serial bus core for those drivers to get that ability.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-04 13:48:32 -08:00
Greg Kroah-Hartman
269bda1c12 [PATCH] USB Serial: move name to driver structure
This fixes up a lot of problems in sysfs with some of the usb serial
drivers, they had incorrect driver names.  Also saves a tiny ammount
of memory.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 16:47:48 -07:00
Greg Kroah-Hartman
18fcac353f [PATCH] USB Serial: get rid of the .owner field in usb_serial_driver
Don't duplicate something that's already in struct driver.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 16:47:48 -07:00
Greg Kroah-Hartman
ea65370d02 [PATCH] USB Serial: rename usb_serial_device_type to usb_serial_driver
I'm tired of trying to explain why a "device_type" is really a driver.
This better describes exactly what this structure is.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 16:47:47 -07:00
Nishanth Aravamudan
22c4386328 [PATCH] drivers/usb: fix-up schedule_timeout() usage
Description: Use schedule_timeout_{,un}interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-12 12:23:44 -07:00
Lonnie Mendez
b9db07fba7 [PATCH] USB: whitespace fixes for cypress_m8 driver
Reading this driver I noticed some trailing whitespaces and tabs so I
removed them with some 80th column fitting and a few more similar
things.

From: Carlo Perassi <carlo@linux.it>
Signed-off-by: Lonnie Mendez <dignome@gmail.com>
Signed-off-by: Carlo Perassi <carlo@linux.it>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-08 16:22:15 -07:00
Lonnie Mendez
25b6f08e3f [PATCH] USB: cypress_m8: add support for the DeLorme Earthmate lt-20
This patch adds support for the DeLorme Earthmate lt-20 to the
cypress_m8 driver.  The device was tested and found to be compatible
with the cypress_m8 driver.  This is a resend with the complete patch
which properly compiles.

Adds support for the DeLorme Earthmate lt-20 to the cypress_m8 driver.

Signed-off-by: Lonnie Mendez <lmendez19@austin.rr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-16 21:44:26 -07:00
Lonnie Mendez
3cb4a4f739 [PATCH] USB cypress_m8: update kernel driver with current source
Fixed problem where setting or retreiving the serial config would fail
with EPIPE.  Removed CRTS toggling so the driver behaves more like other
usbserial adapters.  Issued new interval of 1ms instead of the default
bInterval.  As a result, transfer speed has been substantially
increased.  From avg. 850bps to avg. 3300bps.  Also added new module
parameter 'interval' to tweak the interval in case this change causes
problems for someone.  Cleaned up code and formatting issues so source
is more readable.  Replaced the C++ style comments.  Various other code
cleanups.

Signed-off-by: Lonnie Mendez <lmendez19@austin.rr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-03 23:31:52 -07:00
Steven Cole
093cf723b2 [PATCH] USB: Spelling fixes for drivers/usb.
Here are some spelling corrections for drivers/usb.

cancelation -> cancellation
succesful -> successful
cancelation -> cancellation
decriptor -> descriptor
Initalize -> Initialize
wierd -> weird
Protocoll -> Protocol
occured -> occurred
successfull -> successful
Procesing -> Processing
devide -> divide
Isochronuous -> Isochronous
noticable -> noticeable
Basicly -> Basically
transfering -> transferring
intialize -> initialize
Incomming -> Incoming
additionnal -> additional
asume -> assume
Unfortunatly -> Unfortunately
retreive -> retrieve
tranceiver -> transceiver
Compatiblity -> Compatibility
Incorprated -> Incorporated
existance -> existence
Ununsual -> Unusual

Signed-off-by: Steven Cole <elenstev@mesatop.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-03 23:31:52 -07:00
Jesper Juhl
1bc3c9e1e4 [PATCH] USB: kfree cleanup for drivers/usb/* - no need to check for NULL
Get rid of a bunch of redundant NULL pointer checks in drivers/usb/*,
there's no need to check a pointer for NULL before calling kfree() on it.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>


Index: gregkh-2.6/drivers/usb/class/audio.c
===================================================================
2005-04-18 17:39:34 -07:00