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 its 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.)