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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 00:20:36 +0200
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/ChangeLog
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
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!
Diffstat (limited to 'drivers/char/ChangeLog')
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diff --git a/drivers/char/ChangeLog b/drivers/char/ChangeLog
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@@ -0,0 +1,775 @@
+2001-08-11 Tim Waugh <twaugh@redhat.com>
+
+ * serial.c (get_pci_port): Deal with awkward Titan cards.
+
+1998-08-26 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (rs_open): Correctly decrement the module in-use count
+ on errors.
+
+Thu Feb 19 14:24:08 1998 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (tty_name): Remove the non-reentrant (and non-SMP safe)
+ version of tty_name, and rename the reentrant _tty_name
+ function to be tty_name.
+ (tty_open): Add a warning message stating callout devices
+ are deprecated.
+
+Mon Dec 1 08:24:15 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (tty_get_baud_rate): Print a warning syslog if the
+ tty->alt_speed kludge is used; this means the system is
+ using the deprecated SPD_HI ioctls.
+
+Mon Nov 24 10:37:49 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c, esp.c, rocket.c: Change drivers to take advantage of
+ tty_get_baud_rate().
+
+ * tty_io.c (tty_get_baud_rate): New function which computes the
+ correct baud rate for the tty. More factoring out of
+ common code out of the serial driver to the high-level tty
+ functions....
+
+Sat Nov 22 07:53:36 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c, esp.c, rocket.c: Add tty->driver.break() routine, and
+ allow high-level tty code to handle the break and soft
+ carrier ioctls.
+
+ * tty_ioctl.c (n_tty_ioctl): Support TIOCGSOFTCAR and
+ TIOCSSOFTCAR, so that device drivers don't have to support
+ it.
+
+ * serial.c (autoconfig): Change 16750 test to hopefully eliminate
+ false results by people with strange 16550As being
+ detected as 16750s. Hopefully 16750s will still be
+ detected as 16750, and other weird UARTs won't get poorly
+ autodetected. If this doesn't work, I'll have to disable
+ the auto identification for the 16750.
+
+ * tty_io.c (tty_hangup): Now actually do the tty hangup
+ processing during the timer processing, and disable
+ interrupts while doing the hangup processing. This avoids
+ several nasty race conditions which happened when the
+ hangup processing was done asynchronously.
+ (tty_ioctl): Do break handling in the tty driver if
+ driver's break function is supported.
+ (tty_flip_buffer_push): New exported function which should
+ be used by drivers to push characters in the flip buffer
+ to the tty handler. This may either be done using a task
+ queue function for better CPU efficiency, or directly for
+ low latency operation.
+
+ * serial.c (rs_set_termios): Fix bug rs_set_termios when
+ transitioning away from B0, submitted by Stanislav
+ Voronyi.
+
+Thu Jun 19 20:05:58 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (begin_break, end_break, rs_ioctl): Applied patch
+ to support BSD ioctls to set and clear the break
+ condition explicitly.
+
+ * console.c (scrup, scrdown, insert_line, delete_line): Applied
+ fix suggested by Aaron Tiensivu to speed up block scrolls
+ up and down.
+
+ * n_tty.c (opost_block, write_chan): Added a modified "fast
+ console" patch which processes a block of text via
+ "cooking" efficiently.
+
+Wed Jun 18 15:25:50 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (init_dev, release_dev): Applied fix suggested by Bill
+ Hawes to prevent race conditions in the tty code.
+
+ * n_tty.c (n_tty_chars_in_buffer): Applied fix suggested by Bill
+ Hawes so that n_tty_chars_in_buffer returns the correct
+ value in the case when the tty is in cannonical mode. (To
+ avoid a pty deadlock with telnetd.)
+
+Thu Feb 27 01:53:08 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (change_speed): Add support for the termios flag
+ CMSPAR, which allows the user to select stick parity.
+ (i.e, if PARODD is set, the parity bit is always 1; if
+ PARRODD is not set, then the parity bit is always 0).
+
+Wed Feb 26 19:03:10 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (cleanup_module): Fix memory leak when using the serial
+ driver as a module; make sure tmp_buf gets freed!
+
+Tue Feb 25 11:01:59 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (set_modem_info): Add support for setting and clearing
+ the OUT1 and OUT2 bits. (For special case UART's, usually
+ for half-duplex.)
+ (autoconfig, change_speed): Fix TI 16750 support.
+
+Sun Feb 16 00:14:43 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (release_dev): Add sanity check to make sure there are
+ no waiters on tty->read_wait or tty->write_wait.
+
+ * serial.c (rs_init): Don't autoconfig a device if the I/O region
+ is already reserved.
+
+ * serial.c (serial_proc_info): Add support for /proc/serial.
+
+Thu Feb 13 00:49:10 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (receive_chars): When the UART repotrs an overrun
+ condition, it does so with a valid character. Changed to
+ not throw away the valid character, but instead report the
+ overrun after the valid character.
+
+ * serial.c: Added new #ifdef's for some of the advanced serial
+ driver features. A minimal driver that only supports COM
+ 1/2/3/4 without sharing serial interrupts only takes 17k;
+ the full driver takes 32k.
+
+Wed Feb 12 14:50:44 1997 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * vt.c:
+ * pty.c:
+ * tty_ioctl.c:
+ * serial.c: Update routines to use the new 2.1 memory access
+ routines.
+
+Wed Dec 4 07:51:52 1996 Theodore Ts'o <tytso@localhost.mit.edu>
+
+ * serial.c (change_speed): Use save_flags(); cli() and
+ restore_flags() in order to ensure we don't accidentally
+ turn on interrupts when starting up the port.
+ (startup): Move the insertion of serial structure into the
+ IRQ chain earlier into the startup processing. Interrupts
+ should be off this whole time, but we eventually will want
+ to reduce this window.
+
+Thu Nov 21 10:05:22 1996 Theodore Ts'o <tytso@localhost.mit.edu>
+
+ * tty_ioctl.c (tty_wait_until_sent): Always check the driver
+ wait_until_ready routine, even if there are no characters
+ in the xmit buffer. (There may be charactes in the device
+ FIFO.)
+ (n_tty_ioctl): Add new flag tty->flow_stopped which
+ indicates whether the tty is stopped due to a request by
+ the TCXONC ioctl (used by tcflow). If so, don't let an
+ incoming XOFF character restart the tty. The tty can only
+ be restarted by another TCXONC request.
+
+ * tty_io.c (start_tty): Don't allow the tty to be restarted if
+ tty->flow_stopped is true.
+
+ * n_tty.c (n_tty_receive_char): If tty->flow_stopped is true, and
+ IXANY is set, don't eat a character trying to restart the
+ tty.
+
+ * serial.c (startup): Remove need for MCR_noint from the
+ async_struct structure. Only turn on DTR and RTS if the
+ baud rate is not zero.
+ (change_speed): More accurately calculate the timeout
+ value based on the word size. Move responsibility of
+ hangup when speed becomes B0 to rs_set_termios()
+ (set_serial_info): When changing the UART type set the
+ current xmit_fifo_size as well as the permanent
+ xmit_fifo_size.
+ (rs_ioctl): Fix TCSBRK (used by tcdrain) and TCSBRKP
+ ioctls to return EINTR if interrupted by a signal.
+ (rs_set_termios): If the baud rate changes to or from B0,
+ this function is now responsible for setting or clearing
+ DTR and RTS. DTR and RTS are only be changed on the
+ transition to or from the B0 state.
+ (rs_close): Wait for the characters to drain based on
+ info->timeout. At low baud rates (50 bps), it may take a
+ long time for the FIFO to completely drain out!
+ (rs_wait_until_sent): Fixed timeout handling. Now
+ releases control to the scheduler, but checks frequently
+ enough so that the function is sensitive enough to pass
+ the timing requirements of the NIST-PCTS.
+ (block_til_ready): When opening the device, don't turn on
+ DTR and RTS if the baud rate is B0.
+
+Thu Nov 14 00:06:09 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c (autoconfig): Fix autoconfiguration problems;
+ info->flags wasn't getting initialized from the state
+ structure. Put in more paranoid test for the 16750.
+
+Fri Nov 8 20:19:50 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * n_tty.c (n_tty_flush_buffer): Only call driver->unthrottle() if
+ the tty was previous throttled.
+ (n_tty_set_termios, write_chan): Add changes suggested by
+ Simon P. Allen to allow hardware cooking.
+
+ * tty_ioctl.c (set_termios): If we get a signal while waiting for
+ the tty to drain, return -EINTR.
+
+ * serial.c (change_speed): Add support for CREAD, as required by
+ POSIX.
+
+Sat Nov 2 20:43:10 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * serial.c: Wholesale changes. Added support for the Startech
+ 16650 and 16650V2 chips. (WARNING: the new startech
+ 16650A may or may not work!) Added support for the
+ TI16750 (not yet tested). Split async_struct into a
+ transient part (async_struct) and a permanent part
+ (serial_state) which contains the configuration
+ information for the ports. Added new driver routines
+ wait_until_sent() and send_xchar() to help with POSIX
+ compliance. Added support for radio clocks which waggle
+ the carrier detect line (CONFIG_HARD_PPS).
+
+ * tty_ioctl.c (tty_wait_until_sent): Added call to new driver
+ function tty->driver.wait_until_sent(), which returns when
+ the tty's device xmit buffers are drained. Needed for
+ full POSIX compliance.
+
+ (send_prio_char): New function, called by the ioctl's
+ TCIOFF and TCION; uses the new driver call send_xchar(),
+ which will send the XON or XOFF character at high priority
+ (and even if tty output is stopped).
+
+Wed Jun 5 18:52:04 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * pty.c (pty_close): When closing a pty, make sure packet mode is
+ cleared.
+
+Sun May 26 09:33:52 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * vesa_blank.c (set_vesa_blanking): Add missing verify_area() call.
+
+ * selection.c (set_selection): Add missing verify_area() call.
+
+ * tty_io.c (tty_ioctl): Add missing verify_area() calls.
+
+ * serial.c (rs_ioctl): Add missing verify_area() calls.
+ (rs_init): Allow initialization of serial driver
+ configuration from a module.
+
+ * random.c (extract_entropy): Add missing verify_area call.
+ Don't limit number of characters returned to
+ 32,768. Extract entropy is now no longer a inlined
+ function.
+
+ (random_read): Check return value in case extract_entropy
+ returns an error.
+
+ (secure_tcp_sequence_number): New function which returns a
+ secure TCP sequence number. This is needed to prevent some
+ nasty TCP hijacking attacks.
+
+ (init_std_data): Initialize using gettimeofday() instead of
+ struct timeval xtime.
+
+ (fast_add_entropy_word, add_entropy_word): Rename the
+ inline function add_entropy_word() to
+ fast_add_entropy_word(). Make add_entropy_word() be the
+ non-inlined function which is used in non-timing critical
+ places, in order to save space.
+
+ (initialize_benchmark, begin_benchmark, end_benchmark): New
+ functions defined when RANDOM_BENCHMARK is defined. They
+ allow us to benchmark the speed of the
+ add_timer_randomness() call.
+
+ (int_ln, rotate_left): Add two new inline functions with
+ i386 optimized asm instructions. This speeds up the
+ critical add_entropy_word() and add_timer_randomness()
+ functions, which are called from interrupt handlers.
+
+Tue May 7 22:51:11 1996 <tytso@rsts-11.mit.edu>
+
+ * random.c (add_timer_randomness): Limit the amount randomness
+ that we estimate to 12 bits. (An arbitrary amount).
+
+ (extract_entropy): To make it harder to analyze the hash
+ function, fold the hash function in half using XOR, and
+ use the folded result as the value to emit to the user.
+ Also, add timer randomness each pass through the
+ exact_entropy call, to increase the amount of unknown
+ values during the extraction process.
+
+ (random_ioctl): Use IOR/IOW definitions to define the
+ ioctl values used by the /dev/random driver. Allow the
+ old ioctl values to be used for backwards compatibility
+ (for a limited amount of time).
+
+Wed Apr 24 14:02:04 1996 Theodore Ts'o <tytso@rsts-11.mit.edu>
+
+ * random.c (add_timer_randomness): Use 2nd derivative as well to
+ better estimate entropy.
+
+ (rand_initialize): Explicitly initialize all the pointers
+ to NULL. (Clearing pointers using memset isn't portable.)
+ Initialize the random pool with OS-dependent data.
+
+ (random_write): Add sanity checking to the arguments to
+ random_write(), so that bad arguments won't cause a kernel
+ SEGV.
+
+ (random_read): Update the access time of the device inode
+ when you return data to the user.
+
+ (random_ioctl): Wake up the random_wait channel when there
+ are only WAIT_INPUT_BITS available. Add more paranoia
+ checks to make sure entropy_count doesn't go beyond the
+ bounds of (0, POOLSIZE). Add a few missing verify_area
+ checks. Add support for the RNDCLEARPOOL ioctl, which
+ zaps the random pool.
+
+ (add_timer_randomness): Wake up the random_wait
+ channel only when there are WAIT_INPUT_BITS available.
+
+ (random_select): Allow a random refresh daemon process to
+ select on /dev/random for writing; wake up the daemon when
+ there are less than WAIT_OUTPUT_BITS bits of randomness
+ available.
+
+Tue Apr 23 22:56:07 1996 <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (init_dev): Change return code when user attempts to
+ open master pty which is already open from EAGAIN to EIO,
+ to match with BSD expectations. EIO is more correct
+ anyway, since EAGAIN implies that retrying will be
+ successful --- which it might be.... Eventually!!
+
+ * pty.c (pty_open, pty_close): Fix wait loop so that we don't
+ busy loop while waiting for the master side to open.
+ Fix tty opening/closing logic. TTY_SLAVE_CLOSED was
+ renamed to TTY_OTHER_CLOSED, so that the name is more
+ descriptive. Also fixed code so that the tty flag
+ actually works correctly now....
+
+Mon Apr 1 10:22:01 1996 <tytso@rsts-11.mit.edu>
+
+ * serial.c (rs_close): Cleaned up modularization changes.
+ Remove code which forced line discipline back to N_TTY
+ this is done in the tty upper layers, and there's no
+ reason to do it here. (Making this change also
+ removed the requirement that the serial module access
+ the internal kernel symbol "ldiscs".)
+
+ * tty_io.c (tty_init): Formally register a tty_driver entry for
+ /dev/tty (device 4, 0) and /dev/console (device 5, 0).
+ This guarantees that major device numbers 4 and 5 will be
+ reserved for the tty subsystem (as they have to be because
+ of /dev/tty and /dev/console). Removed tty_regdev, as
+ this interface is no longer necessary.
+
+Sun Mar 17 20:42:47 GMT 1996 <ah@doc.ic.ac.uk>
+
+ * serial.c : modularisation (changes in linux/fs/device.c allow
+ kerneld to automatically load the serial module).
+
+ * Makefile, Config.in : serial modularisation adds.
+
+ * tty_io.c : tty_init_ctty used by to register "cua" driver just
+ for the /dev/tty device (5,0). Added tty_regdev.
+
+ * serial.c (shutdown, rs_ioctl) : when port shuts down wakeup processes
+ waiting on delta_msr_wait. The TIOCMIWAIT ioctl returns EIO
+ if no change was done since the time of call.
+
+Sat Mar 16 14:33:13 1996 <aeb@cwi.nl>
+
+ * tty_io.c (disassociate_ctty): If disassociate_ctty is called by
+ exit, do not perform an implicit vhangup on a pty.
+
+Fri Feb 9 14:15:47 1996 <tytso@rsts-11.mit.edu>
+
+ * serial.c (block_til_ready): Fixed another race condition which
+ happens if a hangup happens during the open.
+
+Wed Jan 10 10:08:00 1996 <tytso@rsts-11.mit.edu>
+
+ * serial.c (block_til_ready): Remove race condition which happened
+ if a hangup condition happened during the setup of the
+ UART, before rs_open() called block_til_ready(). This
+ caused the info->count counter to be erroneously
+ decremented.
+
+ * serial.c (startup, rs_open): Remove race condition that could
+ cause a memory leak of one page. (Fortunately, both race
+ conditions were relatively rare in practice.)
+
+Tue Dec 5 13:21:27 1995 <tytso@rsts-11.mit.edu>
+
+ * serial.c (check_modem_status, rs_ioctl): Support the new
+ ioctl()'s TIOCGICOUNT, TIOCMIWAIT. These allow an
+ application program to wait on a modem serial register
+ status bit change, and to find out how many changes have
+ taken place for the MSR bits.
+
+ (rs_write): Eliminate a race condition which is introduced
+ if it is necessary to wait for the semaphore.
+
+Sat Nov 4 17:14:45 1995 <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (tty_init): Move registration of TTY_MAJOR and
+ TTY_AUX_MAJOR to the end, so that /proc/devices looks
+ prettier.
+
+ * pty.c (pty_init): Use new major numbers for PTY master and slave
+ devices. This allow us to have more than 64 pty's. We
+ register the old pty devices for backwards compatibility.
+ Note that a system should either be using the old pty
+ devices or the new pty devices --- in general, it should
+ try to use both, since they map into the same pty table.
+ The old pty devices are strictly for backwards compatibility.
+
+Wed Oct 11 12:45:24 1995 <tytso@rsts-11.mit.edu>
+
+ * tty_io.c (disassociate_ctty): If disassociate_ctty is called by
+ exit, perform an implicit vhangup on the tty.
+
+ * pty.c (pty_close): When the master pty is closed, send a hangup
+ to the slave pty.
+ (pty_open): Use the flag TTY_SLAVE_CLOSED to test to see
+ if there are any open slave ptys, instead of using
+ tty->link->count. The old method got confused if there
+ were processes that had hung-up file descriptors on the
+ slave tty.
+
+Tue May 2 00:53:25 1995 <tytso@rsx-11.mit.edu>
+
+ * tty_io.c (tty_set_ldisc): Wait until the output buffer is
+ drained before closing the old line discipline --- needed
+ in only one case: XON/XOFF processing.
+
+ * n_tty.c (n_tty_close): Don't bother waiting until the output
+ driver is closed; in general, the line discipline
+ shouldn't care if the hardware is finished
+ transmitting before the line discipline terminates.
+
+ * tty_io.c (release_dev): Shutdown the line discipline after
+ decrementing the tty count variable; but set the
+ TTY_CLOSING flag so that we know that this tty structure
+ isn't long for this world.
+
+ * tty_io.c (init_dev): Add sanity code to check to see if
+ TTY_CLOSING is set on a tty structure; if so, something
+ bad has happened (probably a line discipline close blocked
+ when it shouldn't have; so do a kernel printk and then
+ return an error).
+
+Wed Apr 26 10:23:44 1995 Theodore Y. Ts'o <tytso@localhost>
+
+ * tty_io.c (release_dev): Try to shutdown the line discipline
+ *before* decrementing the tty count variable; this removes
+ a potential race condition which occurs when the line
+ discipline close blocks, and another process then tries
+ open the same serial port.
+
+ * serial.c (rs_hangup): When hanging up, flush the output buffer
+ before shutting down the UART. Otherwise the line
+ discipline close blocks waiting for the characters to get
+ flushed, which never happens until the serial port gets reused.
+
+Wed Apr 12 08:06:16 1995 Theodore Y. Ts'o <tytso@localhost>
+
+ * serial.c (do_serial_hangup, do_softint, check_modem_status,
+ rs_init): Hangups are now scheduled via a separate tqueue
+ structure in the async_struct structure, tqueue_hangup.
+ This task is pushed on to the tq_schedule queue, so that
+ it is processed synchronously by the scheduler.
+
+Sat Feb 18 12:13:51 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (disassociate_ctty, tty_open, tty_ioctl): Clear
+ current->tty_old_pgrp field when a session leader
+ acquires a controlling tty, and after a session leader
+ has disassociated from a controlling tty.
+
+Fri Feb 17 09:34:09 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_interrupt_single, rs_interrupt, rs_interrupt_multi):
+ Change the number of passes made from 64 to be 256,
+ configurable with the #define RS_ISR_PASS_LIMIT.
+
+ * serial.c (rs_init, set_serial_info, get_serial_info, rs_close):
+ Remove support for closing_wait2. Instead, set
+ tty->closing and rely on the line discipline to prevent
+ echo wars.
+
+ * n_tty.c (n_tty_receive_char): IEXTEN does not need to be
+ enabled in order for IXANY to be active.
+
+ If tty->closing is set, then only process XON and XOFF
+ characters.
+
+Sun Feb 12 23:57:48 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_timer): Change the interrupt poll time from 60
+ seconds to 10 seconds, configurable with the #define
+ RS_STROBE_TIME.
+
+ * serial.c (rs_interrupt_multi, startup, shutdown, rs_ioctl,
+ set_multiport_struct, get_multiport_struct): Add
+ provisions for a new type of interrupt service routine,
+ which better supports multiple serial ports on a single
+ IRQ.
+
+Sun Feb 5 19:35:11 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_ioctl.c (n_tty_ioctl, set_termios, tty_wait_until_sent):
+ * serial.c (rs_ioctl, rs_close):
+ * cyclades.c (cy_ioctl, cy_close):
+ * n_tty.c (n_tty_close): Rename wait_until_sent to
+ tty_wait_until_sent, so that it's a better name to export
+ in ksyms.c.
+
+Sat Feb 4 23:36:20 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_close): Added missing check for closing_wait2 being
+ ASYNC_CLOSING_WAIT_NONE.
+
+Thu Jan 26 09:02:49 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_init, set_serial_info, get_serial_info,
+ rs_close): Support close_wait in the serial driver.
+ This is helpful for slow devices (like serial
+ plotters) so that their outputs don't get flushed upon
+ device close. This has to be configurable because
+ normally we don't want ports to be hung up for long
+ periods of time during a close when they are not
+ connected to a device, or the device is powered off.
+
+ The default is to wait 30 seconds; in the case of a
+ very slow device, the close_wait timeout should be
+ lengthened. If it is set to 0, the kernel will wait
+ forever for all of the data to be transmitted.
+
+Thu Jan 17 01:17:20 1995 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (startup, change_speed, rs_init): Add support to detect
+ the StarTech 16650 chip. Treat it as a 16450 for now,
+ because of its FIFO bugs.
+
+Thu Jan 5 21:21:57 1995 <dahinds@users.sourceforge.net>
+
+ * serial.c: (receive_char): Added counter to prevent infinite loop
+ when a PCMCIA serial device is ejected.
+
+Thu Dec 29 17:53:48 1994 <tytso@rsx-11.mit.edu>
+
+ * tty_io.c (check_tty_count): New procedure which checks
+ tty->count to make sure that it matches with the number of
+ open file descriptors which point at the structure. If
+ the number doesn't match, it prints a warning message.
+
+Wed Dec 28 15:41:51 1994 <tytso@rsx-11.mit.edu>
+
+ * tty_io.c (do_tty_hangup, disassociate_ctty): At hangup time,
+ save the tty's current foreground process group in the
+ session leader's task structure. When the session leader
+ terminates, send a SIGHUP, SIGCONT to that process group.
+ This is not required by POSIX, but it's not prohibited
+ either, and it appears to be the least intrusive way
+ to fix a problem that dialup servers have with
+ orphaned process groups caused by modem hangups.
+
+Thu Dec 8 14:52:11 1994 <tytso@rsx-11.mit.edu>
+
+ * serial.c (rs_ioctl): Don't allow most ioctl's if the serial port
+ isn't initialized.
+
+ * serial.c (rs_close): Don't clear the IER if the serial port
+ isn't initialized.
+
+ * serial.c (block_til_ready): Don't try to block on the dialin
+ port if the serial port isn't initialized.
+
+Wed Dec 7 10:48:30 1994 Si Park (si@wimpol.demon.co.uk)
+ * tty_io.c (tty_register_driver): Fix bug when linking onto
+ the tty_drivers list. We now test that there are elements
+ already on the list before setting the back link from the
+ first element to the new driver.
+
+ * tty_io.c (tty_unregister_driver): Fix bug in unlinking the
+ specified driver from the tty_drivers list. We were not
+ setting the back link correctly. This used to result in
+ a dangling back link pointer and cause panics on the next
+ call to get_tty_driver().
+
+Tue Nov 29 10:21:09 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (tty_unregister_driver): Fix bug in
+ tty_unregister_driver where the pointer to the refcount is
+ tested, instead of the refcount itself. This caused
+ tty_unregister_driver to always return EBUSY.
+
+Sat Nov 26 11:59:24 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (tty_ioctl): Add support for the new ioctl
+ TIOCTTYGSTRUCT, which allow a kernel debugging program
+ direct read access to the tty and tty_driver structures.
+
+Fri Nov 25 17:26:22 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_set_termios): Don't wake up processes blocked in
+ open when the CLOCAL flag changes, since a blocking
+ open only samples the CLOCAL flag once when it blocks,
+ and doesn't check it again. (n.b. FreeBSD has a
+ different behavior for blocking opens; it's not clear
+ whether Linux or FreeBSD's interpretation is correct.
+ POSIX doesn't give clear guidance on this issue, so
+ this may change in the future....)
+
+ * serial.c (block_til_ready): Use the correct termios structure to
+ check the CLOCAL flag. If the cuaXX device is active,
+ then check the saved termios for the ttySXX device.
+ Otherwise, use the currently active termios structure.
+
+Sun Nov 6 21:05:44 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (change_speed): Add support for direct access of
+ 57,600 and 115,200 bps.
+
+Wed Nov 2 10:32:36 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * n_tty.c (n_tty_receive_room): Only allow excess characters
+ through if we are in ICANON mode *and* there are other no
+ pending lines in the buffer. Otherwise cut and paste over
+ 4k breaks.
+
+Sat Oct 29 18:17:34 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_ioctl, get_lsr_info): Added patch suggested by Arne
+ Riiber so that user mode programs can tell when the
+ transmitter shift register is empty.
+
+Thu Oct 27 23:14:29 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_ioctl.c (wait_until_sent): Added debugging printk statements
+ (under the #ifdef TTY_DEBUG_WAIT_UNTIL_SENT)
+
+ * serial.c (rs_interrupt, rs_interrupt_single, receive_chars,
+ change_speed, rs_close): rs_close now disables receiver
+ interrupts when closing the serial port. This allows the
+ serial port to close quickly when Linux and a modem (or a
+ mouse) are engaged in an echo war; when closing the serial
+ port, we now first stop listening to incoming characters,
+ and *then* wait for the transmit buffer to drain.
+
+ In order to make this change, the info->read_status_mask
+ is now used to control what bits of the line status
+ register are looked at in the interrupt routine in all
+ cases; previously it was only used in receive_chars to
+ select a few of the status bits.
+
+Mon Oct 24 23:36:21 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_close): Add a timeout to the transmitter flush
+ loop; this is just a sanity check in case we have flaky
+ (or non-existent-but-configured-by-the-user) hardware.
+
+Fri Oct 21 09:37:23 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (tty_fasync): When asynchronous I/O is enabled, if the
+ process or process group has not be specified yet, set it
+ to be the tty's process group, or if that is not yet set,
+ to the current process's pid.
+
+Thu Oct 20 23:17:28 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * n_tty.c (n_tty_receive_room): If we are doing input
+ canonicalization, let as many characters through as
+ possible, so that the excess characters can be "beeped".
+
+Tue Oct 18 10:02:43 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_start): Removed an incorrect '!' that was
+ preventing transmit interrupts from being re-enabled in
+ rs_start(). Fortunately in most cases it would be
+ re-enabled elsewhere, but this still should be fixed
+ correctly.
+
+Sun Oct 9 23:46:03 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (do_tty_hangup): If the tty driver flags
+ TTY_DRIVER_RESET_TERMIOS is set, then reset the termios
+ settings back to the driver's initial configuration. This
+ allows the termios settings to be reset even if a process
+ has hung up file descriptors keeping a pty's termios from
+ being freed and reset.
+
+ * tty_io.c (release_dev): Fix memory leak. The pty's other
+ termios structure should also be freed.
+
+ * serial.c (rs_close, shutdown): Change how we wait for the
+ transmitter to completely drain before shutting down the
+ serial port. We now do it by scheduling in another
+ process instead of busy looping with the interrupts turned
+ on. This may eliminate some race condition problems that
+ some people seem to be reporting.
+
+Sun Sep 25 14:18:14 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (release_dev): When freeing a tty make sure that both
+ the tty and the o_tty (if present) aren't a process's
+ controlling tty. (Previously, we only checked the tty.)
+
+ * serial.c (change_speed): Only enable the Modem Status
+ Interrupt for a port if CLOCAL is not set or CRTSCTS
+ is set. If we're not checking the carrier detect and
+ CTS line, there's no point in enabling the modem
+ status interrupt. This will save spurious interrupts
+ from slowing down systems who have terminals that
+ don't support either line. (Of course, if you want
+ only one of CD and CTS support, you will need a
+ properly wired serial cable.)
+
+Thu Sep 22 08:32:48 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (do_SAK): Return if tty is null.
+
+ * tty_io.c (_tty_name): Return "NULL tty" if the passed in tty is
+ NULL.
+
+Sat Sep 17 13:19:25 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_ioctl.c (n_tty_ioctl): Fix TIOCGLCKTRMIOS and
+ TIOCSLCKTRMIOS, which were totally broken. Remove
+ extra indirection from argument; it should be a struct
+ termios *, not a struct termios **.
+ &real_tty->termios_locked should have been
+ real_tty->termios_locked. This caused us to be
+ reading and writing the termios_locked structure to
+ random places in kernel memory.
+
+ * tty_io.c (release_dev): Oops! Forgot to delete a critical kfree
+ of the locked_termios. This leaves the locked_termios
+ structure pointed at a freed object.
+
+Fri Sep 16 08:13:25 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * tty_io.c (tty_open): Don't check for an exclusive open until
+ after the device specific open routine has been called.
+ Otherwise, the serial device ref counting will be screwed
+ up.
+
+ * serial.c (rs_open, block_til_ready): Don't set termios structure
+ until after block_til_ready has returned successfully.
+ Modify block_til_ready to check the normal_termios
+ structure directly, so it doesn't rely on termios being
+ set before it's called.
+
+Thu Sep 15 23:34:01 1994 Theodore Y. Ts'o (tytso@rt-11)
+
+ * serial.c (rs_close): Turn off interrupts during rs_close() to
+ prevent a race condition with the hangup code (which
+ runs during a software interrupt).
+
+ * tty_io.c (release_dev): Don't free the locked_termios structure;
+ its state must be retained across device opens.
+
+
+ * tty_io.c (tty_unregister_driver): Added function to unregister a
+ tty driver. (For loadable device drivers.)
+
+