diff options
| author | Alan Cox | 2008-07-16 21:53:41 +0100 |
|---|---|---|
| committer | Linus Torvalds | 2008-07-20 17:12:35 -0700 |
| commit | 6f67048cd010afe19d79d821f16055d9c704c6f0 (patch) | |
| tree | 1fbd4717f97632a4753ea98555e285483e35cd45 /drivers/char | |
| parent | d87a6d951c6c09d191d9c10903deb3cc353fcd2c (diff) | |
tty: Introduce a tty_port common structure
Every tty driver has its own concept of a port structure and because
they all differ we cannot extract commonality. Begin fixing this by
creating a structure drivers can elect to use so that over time we can
push fields into this and create commonality and then introduce common
methods.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tty_io.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 54c4ada460ee..739c9c59fc62 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -2088,6 +2088,40 @@ ssize_t redirected_tty_write(struct file *file, const char __user *buf, return tty_write(file, buf, count, ppos); } +void tty_port_init(struct tty_port *port) +{ + memset(port, 0, sizeof(*port)); + init_waitqueue_head(&port->open_wait); + init_waitqueue_head(&port->close_wait); + mutex_init(&port->mutex); +} +EXPORT_SYMBOL(tty_port_init); + +int tty_port_alloc_xmit_buf(struct tty_port *port) +{ + /* We may sleep in get_zeroed_page() */ + mutex_lock(&port->mutex); + if (port->xmit_buf == NULL) + port->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL); + mutex_unlock(&port->mutex); + if (port->xmit_buf == NULL) + return -ENOMEM; + return 0; +} +EXPORT_SYMBOL(tty_port_alloc_xmit_buf); + +void tty_port_free_xmit_buf(struct tty_port *port) +{ + mutex_lock(&port->mutex); + if (port->xmit_buf != NULL) { + free_page((unsigned long)port->xmit_buf); + port->xmit_buf = NULL; + } + mutex_unlock(&port->mutex); +} +EXPORT_SYMBOL(tty_port_free_xmit_buf); + + static char ptychar[] = "pqrstuvwxyzabcde"; /** |