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20 commits

Author SHA1 Message Date
Jason Wessel
98fcb5f781 USB: serial: usb_debug,usb_generic_serial: implement sysrq and serial break
The usb_debug driver was modified to implement serial break handling
by using a "magic" data packet comprised of the sequence:

       0x00 0xff 0x01 0xfe   0x00 0xfe 0x01 0xff

When the tty layer requests a serial break the usb_debug driver sends
the magic packet.  On the receiving side the magic packet is thrown
away or a sysrq is activated depending on what kernel .config options
have been set.

The generic serial driver was modified as well as the usb serial
headers to generically implement sysrq processing in the same way the
non usb uart based drivers implement the sysrq handling.  This will
allow other usb serial devices to implement sysrq handling as desired.

The new usb serial functions are named similarly and implemented
similarly to the uart functions as follows:

usb_serial_handle_break <-> uart_handle_break
usb_serial_handle_sysrq_char <-> uart_handle_sysrq_char

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:45 -07:00
Jason Wessel
715b1dc01f USB: usb_debug, usb_generic_serial: implement multi urb write
The usb_debug driver, when used as the console, will always fail to
insert the carriage return and new line sequence as well as randomly
drop console output.  This is a result of only having the single
write_urb and that the tty layer will have a lock that prevents the
processing of the back to back urb requests.

The solution is to allow more than one urb to be outstanding and have
a slightly deeper transmit queue.  The idea and some code is borrowed
from the ftdi_sio usb driver.

The generic usb serial driver was modified so as to allow the classic
method of 1 write urb, or a multi write urb scheme with N allowed
outstanding urbs where N is controlled by max_in_flight_urbs.  When
max_in_flight_urbs in a "struct usb_serial_driver" is non zero the
multi write urb scheme will be used.

The size of 4000 was selected for the usb_debug driver so that the
driver lowers possibility of losing the queued console messages during
the kernel startup.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:45 -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
Leandro Dorileo
78c5b82ee6 tty: Update some of the USB kernel doc
Updates some usb_serial_port members documentation.

Signed-off-by: Leandro Dorileo <ldorileo@gmail.com>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-14 08:48:57 -07:00
Oliver Neukum
f8bece8d91 USB: serial: introduce a flag into the usb serial layer to tell drivers that their URBs are killed due to suspension
This patch introduces a flag into the usb serial layer to tell drivers
that their URBs are killed due to suspension. That is necessary to let
drivers know whether they should report an error back.

Signed-off-by: Oliver Neukum <oneukum@suse.de>

Hi Greg,

this is for 2.6.30. Patches to use this in drivers are under development.

	Regards
		Oliver
2009-03-24 16:20:29 -07:00
Geoff Levand
0b14c3881d USB: Fix spelling in usb/serial.h
Fixes a minor typo in the comments for usb_set_serial_data.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-17 14:40:56 -07:00
Alan Stern
0282b7f2a8 usb-serial: don't release unregistered minors
This patch (as1121) fixes a bug in the USB serial core.  When a device
is unregistered, the core will give back its minors -- even if the
device hasn't been assigned any!

The patch reserves the highest minor value (255) to mean that no minor
was assigned.  It also removes some dead code and does a small style
fixup.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-13 17:32:50 -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
Greg Kroah-Hartman
9aebfd6bda USB: serial: remove endpoints setting checks from core and header
Remove the unused check for num_interrupt and friends as well as remove
them from the header file because no usb-serial drivers no longer
reference them.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:52 -07:00
Robert P. J. Day
dda43a0e03 USB: Standardize inclusion protection and add where missing.
For the header files in include/linux/usb, add missing multiple
inclusion protection and standardize what's already there.  The
apparent standards:

  * macro name of __LINUX_USB_headerfile_H
  * inclusion protection placed after leading comment block
  * macro name added as a comment on the final #endif
  * any obvious trivial whitespace cleanup associated with the above

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:42 -07:00
Greg Kroah-Hartman
41dceed51f USB: fix codingstyle issues in include/linux/usb/
Fixes a number of coding style issues in the USB public header files.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 14:35:07 -08:00
Oliver Neukum
a1cd7e99b3 USB: stop io performed by mos7720 upon close()
This fixes a problem where the mos7720 driver will make io to a device from
which it has been logically disconnected. It does so by introducing a flag by
which the generic usb serial code can signal the subdrivers their
disconnection and appropriate locking.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 14:35:03 -08:00
Aristeu Rozanski
9a6b1efa6f USB: usb_serial: clean tty reference in the last close
When a usb serial adapter is used as console, the usb serial console
driver bumps the open_count on the port struct used but doesn't attach
a real tty to it (only a fake one temporaly). If this port is opened later
using the regular character device interface, the open method won't
initialize the port, which is the expected, and will receive a brand new
tty struct created by tty layer, which will be stored in port->tty.

When the last close is issued, open_count won't be 0 because of the
console usage and the port->tty will still contain the old tty value. This
is the last ttyUSB<n> close so the allocated tty will be freed by the
tty layer. The usb_serial and usb_serial_port are still in use by the
console, so port_free() won't be called (serial_close() ->
usb_serial_put() -> destroy_serial() -> port_free()), so the scheduled
work (port->work, usb_serial_port_work()) will still run. And
usb_serial_port_work() does:
(...)
        tty = port->tty;
        if (!tty)
                return;

        tty_wakeup(tty);
which causes (manually copied):

Faulting instruction address: 0x6b6b6b68
Oops: Kernel access of bad area, sig: 11 [#1]
PREEMPT PowerMac
Modules linked in: binfmt_misc ipv6 nfs lockd nfs_acl sunrpc dm_snapshot dm_mirror dm_mod hfsplus uinput ams input_polldev genrtc cpufreq_powersave i2c_powermac therm_adt746x snd_aoa_codec_tas snd_aoa_fabric_layout snd_aoa joydev snd_aoa_i2sbus snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc pmac_zilog serial_core evdev ide_cd cdrom snd appletouch soundcore snd_aoa_soundbus bcm43xx firmware_class usbhid ieee80211softmac ff_memless firewire_ohci firewire_core ieee80211 ieee80211_crypt crc_itu_t sungem sungem_phy uninorth_agp agpart ssb
NIP: 6b6b6b68 LR: c01b2108 CTR: 6b6b6b6b
REGS: c106de80 TRAP: 0400   Not tainted  (2.6.24-rc2)
MSR: 40009032 <EE,ME,IR,DR>  CR: 82004024  XER: 00000000
TASK = c106b4c0[5] 'events/0' THREAD: c106c000
GPR00: 6b6b6b6b c106df30 c106b4c0 c2d613a0 00009032 00000001 00001a00 00000001
GPR08: 00000008 00000000 00000000 c106c000 42004028 00000000 016ffbe0 0171a724
GPR16: 016ffcf4 00240e24 00240e70 016fee68 016ff9a4 c03046c4 c0327f50 c03046fc
GPR24: c106b6b9 c106b4c0 c101d610 c106c000 c02160fc c1eac1dc c2d613ac c2d613a0
NIP [6b6b6b68] 0x6b6b6b68
LR [c01b2108] tty_wakeup+0x6c/0x9c
Call Trace:
[c106df30] [c01b20e8] tty_wakeup+0x4c/0x9c (unreliable)
[c106df40] [c0216138] usb_serial_port_work+0x3c/0x78
[c106df50] [c00432e8] run_workqueue+0xc4/0x15c
[c106df90] [c0043798] worker_thread+0xa0/0x124
[c106dfd0] [c0048224] kthread+0x48/0x84
[c106dff0] [c00129bc] kernel_thread+0x44/0x60
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
Slab corruption: size-2048 start=c2d613a0, len=2048
Redzone: 0x9f911029d74e35b/0x9f911029d74e35b.
Last user: [<c01b16d8>](release_one_tty+0xbc/0xf4)
050: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Prev obj: start=c2d60b88, len=2048
Redzone: 0x9f911029d74e35b/0x9f911029d74e35b.
Last user: [<c00f30ec>](show_stat+0x410/0x428)
000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b

This patch avoids this, clearing port->tty considering if the port is
used as serial console or not

Signed-off-by: Aristeu Rozanski <arozansk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 14:34:50 -08:00
Alan Stern
063a2da8f0 USB: serial core should respect driver requirements
This patch (as997) fixes a bug in the USB serial core.  The core needs
to pay attention to drivers' requirements regarding the number and
type of endpoints a device has.

At the same time, the patch changes the NUM_DONT_CARE constant (which
is stored in a single-byte field) from -1 to a safer, unsigned value.
It also improves the kerneldoc for several fields in the
usb_serial_driver structure.

Finally, the patch replaces a list_for_each() with list_for_each_entry().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:34 -07:00
Oliver Neukum
ec22559e0b USB: suspend support for usb serial
this implements generic support for suspend/resume for usb serial.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-12 16:29:44 -07:00
Joris van Rantwijk
253ca92328 USB: add flow control to usb-serial generic driver.
I added two fields to struct usb_serial_port to keep track of the
throttle state. Other usb-serial drivers typically use private data for
such things, but the generic driver can not really do that because some
of its code is also used by other drivers (which may have their own
private data needs).

As it is, I am not sure that this patch is useful in all scenarios.
It is certainly helpful for low-bandwidth devices that can hold their
data in response to throttling. But for devices that pump data in
real-time as fast as possible (webcam, A/D converter, etc), throttling
may actually cause more data loss.

From: Joris van Rantwijk <jorispubl@xs4all.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 15:32:18 -08:00
Greg Kroah-Hartman
93bacefc4c USB serial: add dynamic id support to usb-serial core
Thanks to Johannes Hölzl <johannes.hoelzl@gmx.de> for fixing a few
things and getting it all working properly.

This adds support for dynamic usb ids to the usb serial core.  The file
"new_id" will show up under the usb serial driver, not the usb driver
associated with the usb-serial driver (yeah, it can be a bit confusing
at first glance...)

This patch also modifies the USB core to allow the usb-serial core to
reuse much of the dynamic id logic.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Johannes Hölzl <johannes.hoelzl@gmx.de>
2007-02-07 15:44:33 -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
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
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
Renamed from drivers/usb/serial/usb-serial.h (Browse further)