drivers/char/ChangeLog

   1 2001-08-11  Tim Waugh  <twaugh@redhat.com>
   2
   3         * serial.c (get_pci_port): Deal with awkward Titan cards.
   4
   5 1998-08-26  Theodore Ts'o  <tytso@rsts-11.mit.edu>
   6
   7         * serial.c (rs_open): Correctly decrement the module in-use count
   8                 on errors.
   9
  10 Thu Feb 19 14:24:08 1998  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  11
  12         * tty_io.c (tty_name): Remove the non-reentrant (and non-SMP safe)
  13                 version of tty_name, and rename the reentrant _tty_name
  14                 function to be tty_name.
  15                 (tty_open): Add a warning message stating callout devices
  16                 are deprecated.
  17
  18 Mon Dec  1 08:24:15 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  19
  20         * tty_io.c (tty_get_baud_rate): Print a warning syslog if the
  21                 tty->alt_speed kludge is used; this means the system is
  22                 using the deprecated SPD_HI ioctls.
  23
  24 Mon Nov 24 10:37:49 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  25
  26         * serial.c, esp.c, rocket.c: Change drivers to take advantage of
  27                 tty_get_baud_rate().
  28
  29         * tty_io.c (tty_get_baud_rate): New function which computes the
  30                 correct baud rate for the tty.  More factoring out of
  31                 common code out of the serial driver to the high-level tty
  32                 functions....
  33
  34 Sat Nov 22 07:53:36 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  35
  36         * serial.c, esp.c, rocket.c: Add tty->driver.break() routine, and
  37                 allow high-level tty code to handle the break and soft
  38                 carrier ioctls.
  39
  40         * tty_ioctl.c (n_tty_ioctl): Support TIOCGSOFTCAR and
  41                 TIOCSSOFTCAR, so that device drivers don't have to support
  42                 it.
  43
  44         * serial.c (autoconfig): Change 16750 test to hopefully eliminate
  45                 false results by people with strange 16550As being
  46                 detected as 16750s.  Hopefully 16750s will still be
  47                 detected as 16750, and other weird UARTs won't get poorly
  48                 autodetected.  If this doesn't work, I'll have to disable
  49                 the auto identification for the 16750.
  50
  51         * tty_io.c (tty_hangup): Now actually do the tty hangup
  52                 processing during the timer processing, and disable
  53                 interrupts while doing the hangup processing.  This avoids
  54                 several nasty race conditions which happened when the
  55                 hangup processing was done asynchronously.
  56                 (tty_ioctl): Do break handling in the tty driver if
  57                 driver's break function is supported.
  58                 (tty_flip_buffer_push): New exported function which should
  59                 be used by drivers to push characters in the flip buffer
  60                 to the tty handler.  This may either be done using a task
  61                 queue function for better CPU efficiency, or directly for
  62                 low latency operation.
  63
  64         * serial.c (rs_set_termios): Fix bug rs_set_termios when
  65                 transitioning away from B0, submitted by Stanislav
  66                 Voronyi.
  67
  68 Thu Jun 19 20:05:58 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  69
  70         * serial.c (begin_break, end_break, rs_ioctl): Applied patch
  71                 to support BSD ioctls to set and clear the break
  72                 condition explicitly.
  73
  74         * console.c (scrup, scrdown, insert_line, delete_line): Applied
  75                 fix suggested by Aaron Tiensivu to speed up block scrolls
  76                 up and down.
  77
  78         * n_tty.c (opost_block, write_chan): Added a modified "fast
  79                 console" patch which processes a block of text via
  80                 "cooking" efficiently.
  81
  82 Wed Jun 18 15:25:50 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  83
  84         * tty_io.c (init_dev, release_dev): Applied fix suggested by Bill
  85                 Hawes to prevent race conditions in the tty code.
  86
  87         * n_tty.c (n_tty_chars_in_buffer): Applied fix suggested by Bill
  88                 Hawes so that n_tty_chars_in_buffer returns the correct
  89                 value in the case when the tty is in cannonical mode.  (To
  90                 avoid a pty deadlock with telnetd.)
  91
  92 Thu Feb 27 01:53:08 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
  93
  94         * serial.c (change_speed): Add support for the termios flag
  95                 CMSPAR, which allows the user to select stick parity.
  96                 (i.e, if PARODD is set, the parity bit is always 1; if
  97                 PARRODD is not set, then the parity bit is always 0).
  98
  99 Wed Feb 26 19:03:10 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 100
 101         * serial.c (cleanup_module): Fix memory leak when using the serial
 102                 driver as a module; make sure tmp_buf gets freed!
 103
 104 Tue Feb 25 11:01:59 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 105
 106         * serial.c (set_modem_info): Add support for setting and clearing
 107                 the OUT1 and OUT2 bits.  (For special case UART's, usually
 108                 for half-duplex.)
 109                 (autoconfig, change_speed): Fix TI 16750 support.
 110
 111 Sun Feb 16 00:14:43 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 112
 113         * tty_io.c (release_dev): Add sanity check to make sure there are
 114                 no waiters on tty->read_wait or tty->write_wait.
 115
 116         * serial.c (rs_init): Don't autoconfig a device if the I/O region
 117                 is already reserved.
 118
 119         * serial.c (serial_proc_info): Add support for /proc/serial.
 120
 121 Thu Feb 13 00:49:10 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 122
 123         * serial.c (receive_chars): When the UART repotrs an overrun
 124                 condition, it does so with a valid character.  Changed to
 125                 not throw away the valid character, but instead report the
 126                 overrun after the valid character.
 127
 128         * serial.c: Added new #ifdef's for some of the advanced serial
 129                 driver features.  A minimal driver that only supports COM
 130                 1/2/3/4 without sharing serial interrupts only takes 17k;
 131                 the full driver takes 32k.
 132
 133 Wed Feb 12 14:50:44 1997  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 134
 135         * vt.c:
 136         * pty.c:
 137         * tty_ioctl.c:
 138         * serial.c: Update routines to use the new 2.1 memory access
 139                 routines.
 140
 141 Wed Dec  4 07:51:52 1996  Theodore Ts'o  <tytso@localhost.mit.edu>
 142
 143         * serial.c (change_speed): Use save_flags(); cli() and
 144                 restore_flags() in order to ensure we don't accidentally
 145                 turn on interrupts when starting up the port.
 146                 (startup): Move the insertion of serial structure into the
 147                 IRQ chain earlier into the startup processing.  Interrupts
 148                 should be off this whole time, but we eventually will want
 149                 to reduce this window.
 150
 151 Thu Nov 21 10:05:22 1996  Theodore Ts'o  <tytso@localhost.mit.edu>
 152
 153         * tty_ioctl.c (tty_wait_until_sent): Always check the driver
 154                 wait_until_ready routine, even if there are no characters
 155                 in the xmit buffer.  (There may be charactes in the device
 156                 FIFO.)
 157                 (n_tty_ioctl): Add new flag tty->flow_stopped which
 158                 indicates whether the tty is stopped due to a request by
 159                 the TCXONC ioctl (used by tcflow).  If so, don't let an
 160                 incoming XOFF character restart the tty.  The tty can only
 161                 be restarted by another TCXONC request.
 162
 163         * tty_io.c (start_tty): Don't allow the tty to be restarted if
 164                 tty->flow_stopped is true.
 165
 166         * n_tty.c (n_tty_receive_char): If tty->flow_stopped is true, and
 167                 IXANY is set, don't eat a character trying to restart the
 168                 tty.
 169
 170         * serial.c (startup): Remove need for MCR_noint from the
 171                 async_struct structure.  Only turn on DTR and RTS if the
 172                 baud rate is not zero.
 173                 (change_speed): More accurately calculate the timeout
 174                 value based on the word size.  Move responsibility of
 175                 hangup when speed becomes B0 to rs_set_termios()
 176                 (set_serial_info): When changing the UART type set the
 177                 current xmit_fifo_size as well as the permanent
 178                 xmit_fifo_size.
 179                 (rs_ioctl): Fix TCSBRK (used by tcdrain) and TCSBRKP
 180                 ioctls to return EINTR if interrupted by a signal.
 181                 (rs_set_termios): If the baud rate changes to or from B0,
 182                 this function is now responsible for setting or clearing
 183                 DTR and RTS.  DTR and RTS are only be changed on the
 184                 transition to or from the B0 state.
 185                 (rs_close): Wait for the characters to drain based on
 186                 info->timeout.  At low baud rates (50 bps), it may take a
 187                 long time for the FIFO to completely drain out!
 188                 (rs_wait_until_sent): Fixed timeout handling.  Now
 189                 releases control to the scheduler, but checks frequently
 190                 enough so that the function is sensitive enough to pass
 191                 the timing requirements of the NIST-PCTS.
 192                 (block_til_ready): When opening the device, don't turn on
 193                 DTR and RTS if the baud rate is B0.
 194
 195 Thu Nov 14 00:06:09 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 196
 197         * serial.c (autoconfig): Fix autoconfiguration problems;
 198                 info->flags wasn't getting initialized from the state
 199                 structure.  Put in more paranoid test for the 16750.
 200
 201 Fri Nov  8 20:19:50 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 202
 203         * n_tty.c (n_tty_flush_buffer): Only call driver->unthrottle() if
 204                 the tty was previous throttled.
 205                 (n_tty_set_termios, write_chan): Add changes suggested by
 206                         Simon P. Allen to allow hardware cooking.
 207
 208         * tty_ioctl.c (set_termios): If we get a signal while waiting for
 209                 the tty to drain, return -EINTR.
 210
 211         * serial.c (change_speed): Add support for CREAD, as required by
 212                 POSIX.
 213
 214 Sat Nov  2 20:43:10 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 215
 216         * serial.c: Wholesale changes.  Added support for the Startech
 217                 16650 and 16650V2 chips.  (WARNING: the new startech
 218                 16650A may or may not work!)  Added support for the
 219                 TI16750 (not yet tested).  Split async_struct into a
 220                 transient part (async_struct) and a permanent part
 221                 (serial_state) which contains the configuration
 222                 information for the ports.  Added new driver routines
 223                 wait_until_sent() and send_xchar() to help with POSIX
 224                 compliance.  Added support for radio clocks which waggle
 225                 the carrier detect line (CONFIG_HARD_PPS).
 226
 227         * tty_ioctl.c (tty_wait_until_sent): Added call to new driver
 228                 function tty->driver.wait_until_sent(), which returns when
 229                 the tty's device xmit buffers are drained.  Needed for
 230                 full POSIX compliance.
 231
 232                 (send_prio_char): New function, called by the ioctl's
 233                 TCIOFF and TCION; uses the new driver call send_xchar(),
 234                 which will send the XON or XOFF character at high priority
 235                 (and even if tty output is stopped).
 236
 237 Wed Jun  5 18:52:04 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 238
 239         * pty.c (pty_close): When closing a pty, make sure packet mode is
 240                 cleared.
 241
 242 Sun May 26 09:33:52 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 243
 244         * vesa_blank.c (set_vesa_blanking): Add missing verify_area() call.
 245
 246         * selection.c (set_selection): Add missing verify_area() call.
 247
 248         * tty_io.c (tty_ioctl): Add missing verify_area() calls.
 249
 250         * serial.c (rs_ioctl): Add missing verify_area() calls.
 251                 (rs_init): Allow initialization of serial driver
 252                 configuration from a module.
 253
 254         * random.c (extract_entropy): Add missing verify_area call.
 255                 Don't limit number of characters returned to
 256                 32,768. Extract entropy is now no longer a inlined
 257                 function.
 258
 259                 (random_read): Check return value in case extract_entropy
 260                 returns an error.
 261
 262                 (secure_tcp_sequence_number): New function which returns a
 263                 secure TCP sequence number.  This is needed to prevent some
 264                 nasty TCP hijacking attacks.
 265
 266                 (init_std_data): Initialize using gettimeofday() instead of
 267                 struct timeval xtime.
 268
 269                 (fast_add_entropy_word, add_entropy_word): Rename the
 270                 inline function add_entropy_word() to
 271                 fast_add_entropy_word().  Make add_entropy_word() be the
 272                 non-inlined function which is used in non-timing critical
 273                 places, in order to save space.
 274
 275                 (initialize_benchmark, begin_benchmark, end_benchmark): New
 276                 functions defined when RANDOM_BENCHMARK is defined.  They
 277                 allow us to benchmark the speed of the
 278                 add_timer_randomness() call.
 279
 280                 (int_ln, rotate_left): Add two new inline functions with
 281                 i386 optimized asm instructions.  This speeds up the
 282                 critical add_entropy_word() and add_timer_randomness()
 283                 functions, which are called from interrupt handlers.
 284
 285 Tue May  7 22:51:11 1996    <tytso@rsts-11.mit.edu>
 286
 287         * random.c (add_timer_randomness): Limit the amount randomness
 288                 that we estimate to 12 bits.  (An arbitrary amount).
 289
 290                 (extract_entropy): To make it harder to analyze the hash
 291                 function, fold the hash function in half using XOR, and
 292                 use the folded result as the value to emit to the user.
 293                 Also, add timer randomness each pass through the
 294                 exact_entropy call, to increase the amount of unknown
 295                 values during the extraction process.
 296
 297                 (random_ioctl): Use IOR/IOW definitions to define the
 298                 ioctl values used by the /dev/random driver.  Allow the
 299                 old ioctl values to be used for backwards compatibility
 300                 (for a limited amount of time).
 301
 302 Wed Apr 24 14:02:04 1996  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 303
 304         * random.c (add_timer_randomness): Use 2nd derivative as well to
 305                 better estimate entropy.
 306
 307                 (rand_initialize): Explicitly initialize all the pointers
 308                 to NULL.  (Clearing pointers using memset isn't portable.)
 309                 Initialize the random pool with OS-dependent data.
 310
 311                 (random_write): Add sanity checking to the arguments to
 312                 random_write(), so that bad arguments won't cause a kernel
 313                 SEGV.
 314
 315                 (random_read): Update the access time of the device inode
 316                 when you return data to the user.
 317
 318                 (random_ioctl): Wake up the random_wait channel when there
 319                 are only WAIT_INPUT_BITS available.  Add more paranoia
 320                 checks to make sure entropy_count doesn't go beyond the
 321                 bounds of (0, POOLSIZE).  Add a few missing verify_area
 322                 checks.  Add support for the RNDCLEARPOOL ioctl, which
 323                 zaps the random pool.
 324
 325                 (add_timer_randomness): Wake up the random_wait
 326                 channel only when there are WAIT_INPUT_BITS available.
 327
 328                 (random_select): Allow a random refresh daemon process to
 329                 select on /dev/random for writing; wake up the daemon when
 330                 there are less than WAIT_OUTPUT_BITS bits of randomness
 331                 available.
 332
 333 Tue Apr 23 22:56:07 1996    <tytso@rsts-11.mit.edu>
 334
 335         * tty_io.c (init_dev): Change return code when user attempts to
 336                 open master pty which is already open from EAGAIN to EIO,
 337                 to match with BSD expectations.  EIO is more correct
 338                 anyway, since EAGAIN implies that retrying will be
 339                 successful --- which it might be.... Eventually!!
 340
 341         * pty.c (pty_open, pty_close): Fix wait loop so that we don't
 342                 busy loop while waiting for the master side to open.
 343                 Fix tty opening/closing logic.  TTY_SLAVE_CLOSED was
 344                 renamed to TTY_OTHER_CLOSED, so that the name is more
 345                 descriptive.  Also fixed code so that the tty flag
 346                 actually works correctly now....
 347
 348 Mon Apr  1 10:22:01 1996    <tytso@rsts-11.mit.edu>
 349
 350         * serial.c (rs_close): Cleaned up modularization changes.
 351                 Remove code which forced line discipline back to N_TTY
 352                 this is done in the tty upper layers, and there's no
 353                 reason to do it here.  (Making this change also
 354                 removed the requirement that the serial module access
 355                 the internal kernel symbol "ldiscs".)
 356
 357         * tty_io.c (tty_init): Formally register a tty_driver entry for
 358                 /dev/tty (device 4, 0) and /dev/console (device 5, 0).
 359                 This guarantees that major device numbers 4 and 5 will be
 360                 reserved for the tty subsystem (as they have to be because
 361                 of /dev/tty and /dev/console).  Removed tty_regdev, as
 362                 this interface is no longer necessary.
 363
 364 Sun Mar 17 20:42:47 GMT 1996 <ah@doc.ic.ac.uk>
 365
 366         * serial.c : modularisation (changes in linux/fs/device.c allow
 367                 kerneld to automatically load the serial module).
 368
 369         * Makefile, Config.in : serial modularisation adds.
 370
 371         * tty_io.c : tty_init_ctty used by to register "cua" driver just
 372                 for the /dev/tty device (5,0).  Added tty_regdev.
 373
 374         * serial.c (shutdown, rs_ioctl) : when port shuts down wakeup processes
 375           waiting on delta_msr_wait. The TIOCMIWAIT ioctl returns EIO
 376           if no change was done since the time of call.
 377
 378 Sat Mar 16 14:33:13 1996 <aeb@cwi.nl>
 379
 380         * tty_io.c (disassociate_ctty): If disassociate_ctty is called by
 381                 exit, do not perform an implicit vhangup on a pty.
 382
 383 Fri Feb  9 14:15:47 1996    <tytso@rsts-11.mit.edu>
 384
 385         * serial.c (block_til_ready): Fixed another race condition which
 386                 happens if a hangup happens during the open.
 387
 388 Wed Jan 10 10:08:00 1996    <tytso@rsts-11.mit.edu>
 389
 390         * serial.c (block_til_ready): Remove race condition which happened
 391                 if a hangup condition happened during the setup of the
 392                 UART, before rs_open() called block_til_ready().  This
 393                 caused the info->count counter to be erroneously
 394                 decremented.
 395
 396         * serial.c (startup, rs_open): Remove race condition that could
 397                 cause a memory leak of one page.  (Fortunately, both race
 398                 conditions were relatively rare in practice.)
 399
 400 Tue Dec  5 13:21:27 1995    <tytso@rsts-11.mit.edu>
 401
 402         * serial.c (check_modem_status, rs_ioctl): Support the new
 403                 ioctl()'s TIOCGICOUNT, TIOCMIWAIT.  These allow an
 404                 application program to wait on a modem serial register
 405                 status bit change, and to find out how many changes have
 406                 taken place for the MSR bits.
 407
 408                 (rs_write): Eliminate a race condition which is introduced
 409                 if it is necessary to wait for the semaphore.
 410
 411 Sat Nov  4 17:14:45 1995    <tytso@rsts-11.mit.edu>
 412
 413         * tty_io.c (tty_init): Move registration of TTY_MAJOR and
 414                 TTY_AUX_MAJOR to the end, so that /proc/devices looks
 415                 prettier.
 416
 417         * pty.c (pty_init): Use new major numbers for PTY master and slave
 418                 devices.  This allow us to have more than 64 pty's.  We
 419                 register the old pty devices for backwards compatibility.
 420                 Note that a system should either be using the old pty
 421                 devices or the new pty devices --- in general, it should
 422                 try to use both, since they map into the same pty table.
 423                 The old pty devices are strictly for backwards compatibility.
 424
 425 Wed Oct 11 12:45:24 1995    <tytso@rsts-11.mit.edu>
 426
 427         * tty_io.c (disassociate_ctty): If disassociate_ctty is called by
 428                 exit, perform an implicit vhangup on the tty.
 429
 430         * pty.c (pty_close): When the master pty is closed, send a hangup
 431                 to the slave pty.
 432                 (pty_open): Use the flag TTY_SLAVE_CLOSED to test to see
 433                 if there are any open slave ptys, instead of using
 434                 tty->link->count.  The old method got confused if there
 435                 were processes that had hung-up file descriptors on the
 436                 slave tty.
 437
 438 Tue May  2 00:53:25 1995    <tytso@rsx-11.mit.edu>
 439
 440         * tty_io.c (tty_set_ldisc): Wait until the output buffer is
 441                 drained before closing the old line discipline --- needed
 442                 in only one case: XON/XOFF processing.
 443
 444         * n_tty.c (n_tty_close): Don't bother waiting until the output
 445                 driver is closed; in general, the line discipline
 446                 shouldn't care if the hardware is finished
 447                 transmitting before the line discipline terminates.
 448
 449         * tty_io.c (release_dev): Shutdown the line discipline after
 450                 decrementing the tty count variable; but set the
 451                 TTY_CLOSING flag so that we know that this tty structure
 452                 isn't long for this world.
 453
 454         * tty_io.c (init_dev): Add sanity code to check to see if
 455                 TTY_CLOSING is set on a tty structure; if so, something
 456                 bad has happened (probably a line discipline close blocked
 457                 when it shouldn't have; so do a kernel printk and then
 458                 return an error).
 459
 460 Wed Apr 26 10:23:44 1995  Theodore Y. Ts'o  <tytso@localhost>
 461
 462         * tty_io.c (release_dev): Try to shutdown the line discipline
 463                 *before* decrementing the tty count variable; this removes
 464                 a potential race condition which occurs when the line
 465                 discipline close blocks, and another process then tries
 466                 open the same serial port.
 467
 468         * serial.c (rs_hangup): When hanging up, flush the output buffer
 469                 before shutting down the UART.  Otherwise the line
 470                 discipline close blocks waiting for the characters to get
 471                 flushed, which never happens until the serial port gets reused.
 472
 473 Wed Apr 12 08:06:16 1995  Theodore Y. Ts'o  <tytso@localhost>
 474
 475         * serial.c (do_serial_hangup, do_softint, check_modem_status,
 476                 rs_init):  Hangups are now scheduled via a separate tqueue
 477                 structure in the async_struct structure, tqueue_hangup.
 478                 This task is pushed on to the tq_schedule queue, so that
 479                 it is processed synchronously by the scheduler.
 480
 481 Sat Feb 18 12:13:51 1995  Theodore Y. Ts'o  (tytso@rt-11)
 482
 483         * tty_io.c (disassociate_ctty, tty_open, tty_ioctl): Clear
 484                 current->tty_old_pgrp field when a session leader
 485                 acquires a controlling tty, and after a session leader
 486                 has disassociated from a controlling tty.
 487
 488 Fri Feb 17 09:34:09 1995  Theodore Y. Ts'o  (tytso@rt-11)
 489
 490         * serial.c (rs_interrupt_single, rs_interrupt, rs_interrupt_multi):
 491                 Change the number of passes made from 64 to be 256,
 492                 configurable with the #define RS_ISR_PASS_LIMIT.
 493
 494         * serial.c (rs_init, set_serial_info, get_serial_info, rs_close):
 495                 Remove support for closing_wait2.  Instead, set
 496                 tty->closing and rely on the line discipline to prevent
 497                 echo wars.
 498
 499         * n_tty.c (n_tty_receive_char):  IEXTEN does not need to be
 500                 enabled in order for IXANY to be active.
 501
 502                 If tty->closing is set, then only process XON and XOFF
 503                 characters.
 504
 505 Sun Feb 12 23:57:48 1995  Theodore Y. Ts'o  (tytso@rt-11)
 506
 507         * serial.c (rs_timer): Change the interrupt poll time from 60
 508                 seconds to 10 seconds, configurable with the #define
 509                 RS_STROBE_TIME.
 510
 511         * serial.c (rs_interrupt_multi, startup, shutdown, rs_ioctl,
 512                 set_multiport_struct, get_multiport_struct): Add
 513                 provisions for a new type of interrupt service routine,
 514                 which better supports multiple serial ports on a single
 515                 IRQ.
 516
 517 Sun Feb  5 19:35:11 1995  Theodore Y. Ts'o  (tytso@rt-11)
 518
 519         * tty_ioctl.c (n_tty_ioctl, set_termios, tty_wait_until_sent):
 520         * serial.c (rs_ioctl, rs_close):
 521         * cyclades.c (cy_ioctl, cy_close):
 522         * n_tty.c (n_tty_close):  Rename wait_until_sent to
 523                 tty_wait_until_sent, so that it's a better name to export
 524                 in ksyms.c.
 525
 526 Sat Feb  4 23:36:20 1995  Theodore Y. Ts'o  (tytso@rt-11)
 527
 528         * serial.c (rs_close): Added missing check for closing_wait2 being
 529                 ASYNC_CLOSING_WAIT_NONE.
 530
 531 Thu Jan 26 09:02:49 1995  Theodore Y. Ts'o  (tytso@rt-11)
 532
 533         * serial.c (rs_init, set_serial_info, get_serial_info,
 534                 rs_close): Support close_wait in the serial driver.
 535                 This is helpful for slow devices (like serial
 536                 plotters) so that their outputs don't get flushed upon
 537                 device close.  This has to be configurable because
 538                 normally we don't want ports to be hung up for long
 539                 periods of time during a close when they are not
 540                 connected to a device, or the device is powered off.
 541
 542                 The default is to wait 30 seconds; in the case of a
 543                 very slow device, the close_wait timeout should be
 544                 lengthened.  If it is set to 0, the kernel will wait
 545                 forever for all of the data to be transmitted.
 546
 547 Thu Jan 17 01:17:20 1995  Theodore Y. Ts'o  (tytso@rt-11)
 548
 549         * serial.c (startup, change_speed, rs_init): Add support to detect
 550                 the StarTech 16650 chip.  Treat it as a 16450 for now,
 551                 because of its FIFO bugs.
 552
 553 Thu Jan  5 21:21:57 1995  <dahinds@users.sourceforge.net>
 554
 555         * serial.c: (receive_char): Added counter to prevent infinite loop
 556                 when a PCMCIA serial device is ejected.
 557
 558 Thu Dec 29 17:53:48 1994    <tytso@rsx-11.mit.edu>
 559
 560         * tty_io.c (check_tty_count): New procedure which checks
 561                 tty->count to make sure that it matches with the number of
 562                 open file descriptors which point at the structure.  If
 563                 the number doesn't match, it prints a warning message.
 564
 565 Wed Dec 28 15:41:51 1994    <tytso@rsx-11.mit.edu>
 566
 567         * tty_io.c (do_tty_hangup, disassociate_ctty): At hangup time,
 568                 save the tty's current foreground process group in the
 569                 session leader's task structure.  When the session leader
 570                 terminates, send a SIGHUP, SIGCONT to that process group.
 571                 This is not required by POSIX, but it's not prohibited
 572                 either, and it appears to be the least intrusive way
 573                 to fix a problem that dialup servers have with
 574                 orphaned process groups caused by modem hangups.
 575
 576 Thu Dec  8 14:52:11 1994    <tytso@rsx-11.mit.edu>
 577
 578         * serial.c (rs_ioctl): Don't allow most ioctl's if the serial port
 579                 isn't initialized.
 580
 581         * serial.c (rs_close): Don't clear the IER if the serial port
 582                 isn't initialized.
 583
 584         * serial.c (block_til_ready): Don't try to block on the dialin
 585                 port if the serial port isn't initialized.
 586
 587 Wed Dec  7 10:48:30 1994  Si Park (si@wimpol.demon.co.uk)
 588         * tty_io.c (tty_register_driver): Fix bug when linking onto
 589                 the tty_drivers list. We now test that there are elements
 590                 already on the list before setting the back link from the
 591                 first element to the new driver.
 592
 593         * tty_io.c (tty_unregister_driver): Fix bug in unlinking the
 594                 specified driver from the tty_drivers list. We were not
 595                 setting the back link correctly. This used to result in
 596                 a dangling back link pointer and cause panics on the next
 597                 call to get_tty_driver().
 598
 599 Tue Nov 29 10:21:09 1994  Theodore Y. Ts'o  (tytso@rt-11)
 600
 601         * tty_io.c (tty_unregister_driver): Fix bug in
 602                 tty_unregister_driver where the pointer to the refcount is
 603                 tested, instead of the refcount itself.  This caused
 604                 tty_unregister_driver to always return EBUSY.
 605
 606 Sat Nov 26 11:59:24 1994  Theodore Y. Ts'o  (tytso@rt-11)
 607
 608         * tty_io.c (tty_ioctl): Add support for the new ioctl
 609                 TIOCTTYGSTRUCT, which allow a kernel debugging program
 610                 direct read access to the tty and tty_driver structures.
 611
 612 Fri Nov 25 17:26:22 1994  Theodore Y. Ts'o  (tytso@rt-11)
 613
 614         * serial.c (rs_set_termios): Don't wake up processes blocked in
 615                 open when the CLOCAL flag changes, since a blocking
 616                 open only samples the CLOCAL flag once when it blocks,
 617                 and doesn't check it again.  (n.b.  FreeBSD has a
 618                 different behavior for blocking opens; it's not clear
 619                 whether Linux or FreeBSD's interpretation is correct.
 620                 POSIX doesn't give clear guidance on this issue, so
 621                 this may change in the future....)
 622
 623         * serial.c (block_til_ready): Use the correct termios structure to
 624                 check the CLOCAL flag.  If the cuaXX device is active,
 625                 then check the saved termios for the ttySXX device.
 626                 Otherwise, use the currently active termios structure.
 627
 628 Sun Nov  6 21:05:44 1994  Theodore Y. Ts'o  (tytso@rt-11)
 629
 630         * serial.c (change_speed): Add support for direct access of
 631                 57,600 and 115,200 bps.
 632
 633 Wed Nov  2 10:32:36 1994  Theodore Y. Ts'o  (tytso@rt-11)
 634
 635         * n_tty.c (n_tty_receive_room): Only allow excess characters
 636                 through if we are in ICANON mode *and* there are other no
 637                 pending lines in the buffer.  Otherwise cut and paste over
 638                 4k breaks.
 639
 640 Sat Oct 29 18:17:34 1994  Theodore Y. Ts'o  (tytso@rt-11)
 641
 642         * serial.c (rs_ioctl, get_lsr_info): Added patch suggested by Arne
 643                 Riiber so that user mode programs can tell when the
 644                 transmitter shift register is empty.
 645
 646 Thu Oct 27 23:14:29 1994  Theodore Y. Ts'o  (tytso@rt-11)
 647
 648         * tty_ioctl.c (wait_until_sent): Added debugging printk statements
 649                 (under the #ifdef TTY_DEBUG_WAIT_UNTIL_SENT)
 650
 651         * serial.c (rs_interrupt, rs_interrupt_single, receive_chars,
 652                 change_speed, rs_close): rs_close now disables receiver
 653                 interrupts when closing the serial port.  This allows the
 654                 serial port to close quickly when Linux and a modem (or a
 655                 mouse) are engaged in an echo war; when closing the serial
 656                 port, we now first stop listening to incoming characters,
 657                 and *then* wait for the transmit buffer to drain.
 658
 659                 In order to make this change, the info->read_status_mask
 660                 is now used to control what bits of the line status
 661                 register are looked at in the interrupt routine in all
 662                 cases; previously it was only used in receive_chars to
 663                 select a few of the status bits.
 664
 665 Mon Oct 24 23:36:21 1994  Theodore Y. Ts'o  (tytso@rt-11)
 666
 667         * serial.c (rs_close): Add a timeout to the transmitter flush
 668                 loop; this is just a sanity check in case we have flaky
 669                 (or non-existent-but-configured-by-the-user) hardware.
 670
 671 Fri Oct 21 09:37:23 1994  Theodore Y. Ts'o  (tytso@rt-11)
 672
 673         * tty_io.c (tty_fasync): When asynchronous I/O is enabled, if the
 674                 process or process group has not be specified yet, set it
 675                 to be the tty's process group, or if that is not yet set,
 676                 to the current process's pid.
 677
 678 Thu Oct 20 23:17:28 1994  Theodore Y. Ts'o  (tytso@rt-11)
 679
 680         * n_tty.c (n_tty_receive_room): If we are doing input
 681                 canonicalization, let as many characters through as
 682                 possible, so that the excess characters can be "beeped".
 683
 684 Tue Oct 18 10:02:43 1994  Theodore Y. Ts'o  (tytso@rt-11)
 685
 686         * serial.c (rs_start): Removed an incorrect '!' that was
 687                 preventing transmit interrupts from being re-enabled in
 688                 rs_start().  Fortunately in most cases it would be
 689                 re-enabled elsewhere, but this still should be fixed
 690                 correctly.
 691
 692 Sun Oct  9 23:46:03 1994  Theodore Y. Ts'o  (tytso@rt-11)
 693
 694         * tty_io.c (do_tty_hangup): If the tty driver flags
 695                 TTY_DRIVER_RESET_TERMIOS is set, then reset the termios
 696                 settings back to the driver's initial configuration.  This
 697                 allows the termios settings to be reset even if a process
 698                 has hung up file descriptors keeping a pty's termios from
 699                 being freed and reset.
 700
 701         * tty_io.c (release_dev): Fix memory leak.  The pty's other
 702                 termios structure should also be freed.
 703
 704         * serial.c (rs_close, shutdown): Change how we wait for the
 705                 transmitter to completely drain before shutting down the
 706                 serial port.  We now do it by scheduling in another
 707                 process instead of busy looping with the interrupts turned
 708                 on.  This may eliminate some race condition problems that
 709                 some people seem to be reporting.
 710
 711 Sun Sep 25 14:18:14 1994  Theodore Y. Ts'o  (tytso@rt-11)
 712
 713         * tty_io.c (release_dev): When freeing a tty make sure that both
 714                 the tty and the o_tty (if present) aren't a process's
 715                 controlling tty.  (Previously, we only checked the tty.)
 716
 717         * serial.c (change_speed): Only enable the Modem Status
 718                 Interrupt for a port if CLOCAL is not set or CRTSCTS
 719                 is set.  If we're not checking the carrier detect and
 720                 CTS line, there's no point in enabling the modem
 721                 status interrupt.  This will save spurious interrupts
 722                 from slowing down systems who have terminals that
 723                 don't support either line.  (Of course, if you want
 724                 only one of CD and CTS support, you will need a
 725                 properly wired serial cable.)
 726
 727 Thu Sep 22 08:32:48 1994  Theodore Y. Ts'o  (tytso@rt-11)
 728
 729         * tty_io.c (do_SAK): Return if tty is null.
 730
 731         * tty_io.c (_tty_name): Return "NULL tty" if the passed in tty is
 732                 NULL.
 733
 734 Sat Sep 17 13:19:25 1994  Theodore Y. Ts'o  (tytso@rt-11)
 735
 736         * tty_ioctl.c (n_tty_ioctl): Fix TIOCGLCKTRMIOS and
 737                 TIOCSLCKTRMIOS, which were totally broken.  Remove
 738                 extra indirection from argument; it should be a struct
 739                 termios *, not a struct termios **.
 740                 &real_tty->termios_locked should have been
 741                 real_tty->termios_locked.  This caused us to be
 742                 reading and writing the termios_locked structure to
 743                 random places in kernel memory.
 744
 745         * tty_io.c (release_dev): Oops!  Forgot to delete a critical kfree
 746                 of the locked_termios.  This leaves the locked_termios
 747                 structure pointed at a freed object.
 748
 749 Fri Sep 16 08:13:25 1994  Theodore Y. Ts'o  (tytso@rt-11)
 750
 751         * tty_io.c (tty_open): Don't check for an exclusive open until
 752                 after the device specific open routine has been called.
 753                 Otherwise, the serial device ref counting will be screwed
 754                 up.
 755
 756         * serial.c (rs_open, block_til_ready): Don't set termios structure
 757                 until after block_til_ready has returned successfully.
 758                 Modify block_til_ready to check the normal_termios
 759                 structure directly, so it doesn't rely on termios being
 760                 set before it's called.
 761
 762 Thu Sep 15 23:34:01 1994  Theodore Y. Ts'o  (tytso@rt-11)
 763
 764         * serial.c (rs_close): Turn off interrupts during rs_close() to
 765                 prevent a race condition with the hangup code (which
 766                 runs during a software interrupt).
 767
 768         * tty_io.c (release_dev): Don't free the locked_termios structure;
 769                 its state must be retained across device opens.
 770
 771
 772         * tty_io.c (tty_unregister_driver): Added function to unregister a
 773                 tty driver.  (For loadable device drivers.)
 774
 775