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  1. 28 4月, 2006 3 次提交
  3. 15 4月, 2006 2 次提交
  5. 21 3月, 2006 2 次提交
  7. 01 3月, 2006 1 次提交
  9. 01 2月, 2006 4 次提交
  11. 11 1月, 2006 1 次提交
    • A
      [PATCH] TTY layer buffering revamp · 33f0f88f
      由 Alan Cox 提交于 
      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: NAlan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: NHirokazu Takata <takata@linux-m32r.org>
Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NJohn Hawkes <hawkes@sgi.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      33f0f88f
  13. 05 1月, 2006 4 次提交
  15. 24 11月, 2005 1 次提交
  17. 29 10月, 2005 6 次提交
  19. 22 9月, 2005 1 次提交
  21. 13 9月, 2005 1 次提交
  23. 09 9月, 2005 2 次提交
    • I
      [PATCH] USB ftdi_sio: New IDs for ELV, Xsens and Falcom products · e6ac4a40
      由 Ian Abbott 提交于 
      This patch for the ftdi_sio driver adds a bunch of new devices and fixes
an incorrect PID:

o Fix PID for ELV UO100 (the PID was in fact for ELV UR100).
o Add PID ELV UR100 (see above) and ELV ALC 8500 Expert.
o Add a whole bunch of other PIDs for ELV USB devices, commented out for
   now as they may be used by other drivers eventually.  (Christian Abt
   of ELV.de submitted a full list of devices including an indication of
   which set of drivers are used by default in the MS Windows world.  We
   decided to comment out the devices that use FTDI's D2XX Windows
   drivers by default.)
o Add PIDs for eight devices from Xsens Technologies BV (submitted in a
   patch against 2.6.12.2 by Patrick Riphagen).
o Add PID for Falcom Samba GPRS modem (submitted by Sebastian Schubert).
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      e6ac4a40
    • I
      [PATCH] USB ftdi_sio: user specified VID/PID · fdcb0a0f
      由 Ian Abbott 提交于 
      ftdi_sio: Support one user specified vendor and product ID via a couple
of new module parameters.
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      fdcb0a0f
  25. 30 7月, 2005 3 次提交
  27. 13 7月, 2005 3 次提交
  29. 21 6月, 2005 1 次提交
  31. 09 6月, 2005 1 次提交
    • I
      [PATCH] USB: ftdi_sio: avoid losing received data in tty-ldisc · 76854cea
      由 Ian Abbott 提交于 
      ftdi_sio: Avoid losing bytes at tty-ldisc.

This patch was originally developed by Daniel Smertnig.  I
(Ian Abbott) made a few changes.  It has been tested by both
Daniel and I, at least for raw, non-canonical receive data
processing.

Here is Daniel's original description of the patch:

===
During a project in which I was using a FTDI 232BM to
transmit data at relative high speeds (625kBit/s), I
noticed a problem where data was lost even if flow
control was enabled: The FTDI-Driver receives 512 Bytes
of data over USB at a time, which consists of 8 64-Byte
packets. Subtracting the 2 bytes of status information
included in each packet this gives 496 "real" data
bytes per read.

This data is passed (indirectly, via the flip buffers)
to the tty line discipline which takes care of
throttling when there the free buffer space reaches
TTY_THRESHOLD_THROTTLE (128). Because the FTDI driver
processes up to 496 bytes at a time, throttling won't
happen in time and the line discipline will discard the
remaining bytes.

To avoid this the patch passes data in 62-byte blocks
to the tty layer and checks the available space in the
ldisc-buffers. If there isn't enough free space,
processing the rest of the data is delayed using a
workqueue.

Note: The original problem should be easily
reproducible with a userspace program which does slow &
small reads.
===
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NDaniel Smertnig <daniel.smertnig@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      76854cea
  33. 01 6月, 2005 1 次提交
  35. 04 5月, 2005 3 次提交
    • S
      [PATCH] USB: Spelling fixes for drivers/usb. · 093cf723
      由 Steven Cole 提交于 
      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: NSteven Cole <elenstev@mesatop.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      093cf723
    • I
      [PATCH] USB: ftdi_sio redundant macro removal · 5e54f91d
      由 Ian Abbott 提交于 
      [ftdi_sio] Replaced redundant INTERFACE_A and INTERFACE_B macros with
the equivalent PIT_SIOA and PIT_SIOB macros.
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      5e54f91d
    • I
      [PATCH] USB: VID/PID updates for ftdi_sio driver · 6f92872c
      由 Ian Abbott 提交于 
      Some VID/PID updates for the ftdi_sio driver:

* The "Gude Analog- und Digitalsysteme GmbH" entries were missing from
  the "combined" table.
* Replaced FTDI_8U232AM_ALT_ALT_PID with 3 PIDs for devices from
  4n-galaxy.de.
* Removed redundant FTDI_RM_VID and renamed FTDI_RMCANVIEW_PID to
  FTDI_RM_CANVIEW_PID.
* Added VID/PID for serial converter in Mobility Electronics EasiDock
  USB 200 (mentioned by Gregory Schmitt).
* Added PID for Active Robots USB comms board (mentioned by John Koch).
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

diff -ur a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
      6f92872c