changelog

powerpc内核mpc8241linux系统下char驱动程序

1998-08-26  Theodore Ts'o  <[e-mail]>

	* serial.c (rs_open): Correctly decrement the module in-use count
		on errors.

Thu Feb 19 14:24:08 1998  Theodore Ts'o  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* 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  <[e-mail]>

	* pty.c (pty_close): When closing a pty, make sure packet mode is
	 	cleared.

Sun May 26 09:33:52 1996  Theodore Ts'o  <[e-mail]>

	* 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    <[e-mail]>

	* 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  <[e-mail]>

	* 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    <[e-mail]>

	* 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    <[e-mail]>

	* 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 <[e-mail]>

	* 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 <[e-mail]>

	* 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    <[e-mail]>

	* 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    <[e-mail]>

	* serial.c (block_til_ready): Remove race condition which happened