void ps2_init(struct ps2dev *ps2dev, struct serio *serio)
{
mutex_init(&ps2dev->cmd_mutex);
lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth);
init_waitqueue_head(&ps2dev->wait);
ps2dev->serio = serio;
}
void tty_set_lock_subclass(struct tty_struct *tty)
{
lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
}
/**
* pty_common_install - set up the pty pair
* @driver: the pty driver
* @tty: the tty being instantiated
* @legacy: true if this is BSD style
*
* Perform the initial set up for the tty/pty pair. Called from the
* tty layer when the port is first opened.
*
* Locking: the caller must hold the tty_mutex
*/
static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
bool legacy)
{
struct tty_struct *o_tty;
struct tty_port *ports[2];
int idx = tty->index;
int retval = -ENOMEM;
/* Opening the slave first has always returned -EIO */
if (driver->subtype != PTY_TYPE_MASTER)
return -EIO;
ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
if (!ports[0] || !ports[1])
goto err;
if (!try_module_get(driver->other->owner)) {
/* This cannot in fact currently happen */
goto err;
}
o_tty = alloc_tty_struct(driver->other, idx);
if (!o_tty)
goto err_put_module;
tty_set_lock_subclass(o_tty);
lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
if (legacy) {
/* We always use new tty termios data so we can do this
the easy way .. */
retval = tty_init_termios(tty);
if (retval)
goto err_deinit_tty;
retval = tty_init_termios(o_tty);
if (retval)
goto err_free_termios;
driver->other->ttys[idx] = o_tty;
driver->ttys[idx] = tty;
} else {
memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
tty->termios = driver->init_termios;
memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
o_tty->termios = driver->other->init_termios;
}
/*
* Everything allocated ... set up the o_tty structure.
*/
tty_driver_kref_get(driver->other);
/* Establish the links in both directions */
tty->link = o_tty;
o_tty->link = tty;
tty_port_init(ports[0]);
tty_port_init(ports[1]);
tty_buffer_set_limit(ports[0], 8192);
tty_buffer_set_limit(ports[1], 8192);
o_tty->port = ports[0];
tty->port = ports[1];
o_tty->port->itty = o_tty;
tty_buffer_set_lock_subclass(o_tty->port);
tty_driver_kref_get(driver);
tty->count++;
o_tty->count++;
return 0;
err_free_termios:
if (legacy)
tty_free_termios(tty);
err_deinit_tty:
deinitialize_tty_struct(o_tty);
free_tty_struct(o_tty);
err_put_module:
module_put(driver->other->owner);
err:
kfree(ports[0]);
kfree(ports[1]);
return retval;
}