Eric Lee / smarc-fsl-linux-kernel

21 Jul, 2008

1 commit

  • a352def21   tty: Ldisc revamp ... Browse Code »

    Move the line disciplines towards a conventional ->ops arrangement. For
    the moment the actual 'tty_ldisc' struct in the tty is kept as part of
    the tty struct but this can then be changed if it turns out that when it
    all settles down we want to refcount ldiscs separately to the tty.

    Pull the ldisc code out of /proc and put it with our ldisc code.

    Signed-off-by: Alan Cox
    Signed-off-by: Linus Torvalds

    Alan Cox
     

30 Apr, 2008

2 commits

  • f34d7a5b7   tty: The big operations rework ... Browse Code »

    - Operations are now a shared const function block as with most other Linux
    objects

    - Introduce wrappers for some optional functions to get consistent behaviour

    - Wrap put_char which used to be patched by the tty layer

    - Document which functions are needed/optional

    - Make put_char report success/fail

    - Cache the driver->ops pointer in the tty as tty->ops

    - Remove various surplus lock calls we no longer need

    - Remove proc_write method as noted by Alexey Dobriyan

    - Introduce some missing sanity checks where certain driver/ldisc
    combinations would oops as they didn't check needed methods were present

    [akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
    [akpm@linux-foundation.org: fix isicom]
    [akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
    [akpm@linux-foundation.org: fix kgdb]
    Signed-off-by: Alan Cox
    Acked-by: Greg Kroah-Hartman
    Cc: Jason Wessel
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     
  • 04f378b19   tty: BKL pushdown ... Browse Code »

    - Push the BKL down into the line disciplines
    - Switch the tty layer to unlocked_ioctl
    - Introduce a new ctrl_lock spin lock for the control bits
    - Eliminate much of the lock_kernel use in n_tty
    - Prepare to (but don't yet) call the drivers with the lock dropped
    on the paths that historically held the lock

    BKL now primarily protects open/close/ldisc change in the tty layer

    [jirislaby@gmail.com: a couple of fixes]
    Signed-off-by: Alan Cox
    Signed-off-by: Jiri Slaby
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

17 Jul, 2007

1 commit

09 May, 2007

1 commit

13 Feb, 2007

1 commit

  • 40565f196   [PATCH] Char: timers cleanup ... Browse Code »

    - Use timer macros to set function and data members and to modify
    expiration time.
    - Use DEFINE_TIMER for global timers and do not init them at run-time in
    these cases.
    - del_timer_sync is common in most cases -- we want to wait for timer
    function if it's still running.

    Signed-off-by: Jiri Slaby
    Cc: Dave Airlie
    Cc: David Woodhouse
    Cc: Dominik Brodowski
    Cc: Alessandro Zummo
    Cc: Paul Fulghum
    Cc: Kylene Jo Hall
    Cc: Wim Van Sebroeck
    Acked-by: Dmitry Torokhov (Input bits)
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jiri Slaby
     

12 Feb, 2007

1 commit

  • 5e07e1ccb   [PATCH] Char: n_r3964, cleanup ... Browse Code »

    - Lindent the code
    - allow semicolons after macros by 'do {} while (0)'
    - eliminate C++ comments

    Signed-off-by: Jiri Slaby
    Cc: David Woodhouse
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jiri Slaby
     

14 Dec, 2006

1 commit

  • 3cec556a8   [PATCH] n_r3964: Use struct pid to track user space clients ... Browse Code »

    Currently this driver tracks user space clients it should send signals to. In
    the presenct of file descriptor passing this is appears susceptible to
    confusion from pid wrap around issues.

    Replacing this with a struct pid prevents us from getting confused, and
    prepares for a pid namespace implementation.

    Signed-off-by: Eric W. Biederman
    Cc: David Woodhouse
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Eric W. Biederman
     

09 Dec, 2006

1 commit

  • 606d099cd   [PATCH] tty: switch to ktermios ... Browse Code »

    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
    Signed-off-by: Martin Peschke
    Acked-by: Peter Oberparleiter
    Cc: Cornelia Huck
    Signed-off-by: Hugh Dickins
    Signed-off-by: Jeff Dike
    Cc: Paolo 'Blaisorblade' Giarrusso
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

26 Jun, 2006

1 commit

11 Jan, 2006

1 commit

  • 33f0f88f1   [PATCH] TTY layer buffering revamp ... Browse Code »

    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
    Cc: Paul Fulghum
    Signed-off-by: Hirokazu Takata
    Signed-off-by: Serge Hallyn
    Signed-off-by: Jeff Dike
    Signed-off-by: John Hawkes
    Signed-off-by: Martin Schwidefsky
    Signed-off-by: Adrian Bunk
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

18 Oct, 2005

1 commit

  • 9ac0b9c19   [PATCH] n_r3964 mod_timer() fix ... Browse Code »

    Since Revision 1.10 was released the n_r3964 module wasn't able to receive any
    data. The reason for that behavior is because there were some wrong calls of
    mod_timer(...) in the function receive_char (...). This patch should fix this
    problem and was successfully tested with talking to some kuka industrial
    robots.

    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Stephan Brodkorb
     

29 Sep, 2005

1 commit

24 Jun, 2005

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    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!

    Linus Torvalds