tmp_buf_sem sems to be a common name for something completely unused...
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> ("usb portion")
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
Minimum data length must be UART_STATE + 1, as data[UART_STATE] is being
accessed for the new line_state. Although PL-2303 hardware is not
expected to send data with exactly UART_STATE length, this keeps it on
the safe side.
Signed-off-by: Horst Schirmeier <horst@schirmeier.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
This patch adds two new Siemens mobiles IDs for the pl2303 driver.
Signed-off-by: Luiz Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These numbers are pointless, as they have not been changed in _years_,
so we should just remove them to stop pretending there is an actual
"version number" for these drivers.
This should also help reduce confusion when people try to ask for
support of a specific driver version, as there has been no way to tell
what they are talking about.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
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>
This patch adds the product ID and vendor ID for a Nokia CA-42 USB cable
to the list of devices handled by the pl2303 driver. The patch is
against 2.6.13.
Signed-off-by: Robert Spanton <rds204@zepler.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This trivial patch makes pl2303 driver work correctly with pl2303HX chip.
Apparently some bug in HX version of pl2303 makes the chip loose some
transmitted bytes or stop working at all after reception of
USB_REQ_CLEAR_FEATURE mesage. Logs generated by UsbSnoop application reveal
that windows driver does not send this type of messages to the converter.
From: "Dariusz M." <D.Marcinkiewicz@elka.pw.edu.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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
===================================================================
Please accept the attached patch which adds the vendorid 0x0745 and
modelid 0x0001 (ID 0745:0001) "Syntech Information Co., Ltd."
The device is an USB IR cradle for a barcode scanner (CPT-8001C) from
Cipherlab.
From: Peter Favrholdt <pfavr@mip.sdu.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff -u kernel-source-2.6.11/drivers/usb/serial/pl2303.c ../kernel-source-2.6.11/drivers/usb/serial/pl2303.c
I'm attaching a patch to fix status when using Siemens X65
mobile. This mobile use first byte instead of normal UART_STATE
byte.
From: Flavio Leitner <fbl@conectiva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Index: gregkh-2.6/drivers/usb/serial/pl2303.c
===================================================================
It's possible to unplug usb device and do tiocmset() and tiocmget() without
valid interface in pl2303 module.
The patch below check this and return -ENODEV if interface was removed.
From: Flavio Leitner <fbl@conectiva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff -purN linux-05-04-11/drivers/usb/serial/pl2303.c linux-05-04-11.usb/drivers/usb/serial/pl2303.c
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
