X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=drivers%2Fserial%2Fserial_core.c;h=c54af8774393ed2a867e0aef1029055d79f8b560;hb=d8aa905b429700e8b6b6b301a8ac2d4a24f2c19b;hp=fcd7744c4253fa390b28806baf3b093d97d82339;hpb=2e6e33bab6e1996a5dec9108fb467b52b841e7a8;p=deliverable%2Flinux.git diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index fcd7744c4253..c54af8774393 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -22,7 +22,6 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#include #include #include #include @@ -1500,20 +1499,18 @@ uart_block_til_ready(struct file *filp, struct uart_state *state) static struct uart_state *uart_get(struct uart_driver *drv, int line) { struct uart_state *state; + int ret = 0; - mutex_lock(&port_mutex); state = drv->state + line; if (mutex_lock_interruptible(&state->mutex)) { - state = ERR_PTR(-ERESTARTSYS); - goto out; + ret = -ERESTARTSYS; + goto err; } state->count++; - if (!state->port) { - state->count--; - mutex_unlock(&state->mutex); - state = ERR_PTR(-ENXIO); - goto out; + if (!state->port || state->port->flags & UPF_DEAD) { + ret = -ENXIO; + goto err_unlock; } if (!state->info) { @@ -1531,15 +1528,17 @@ static struct uart_state *uart_get(struct uart_driver *drv, int line) tasklet_init(&state->info->tlet, uart_tasklet_action, (unsigned long)state); } else { - state->count--; - mutex_unlock(&state->mutex); - state = ERR_PTR(-ENOMEM); + ret = -ENOMEM; + goto err_unlock; } } - - out: - mutex_unlock(&port_mutex); return state; + + err_unlock: + state->count--; + mutex_unlock(&state->mutex); + err: + return ERR_PTR(ret); } /* @@ -1907,9 +1906,12 @@ uart_set_options(struct uart_port *port, struct console *co, static void uart_change_pm(struct uart_state *state, int pm_state) { struct uart_port *port = state->port; - if (port->ops->pm) - port->ops->pm(port, pm_state, state->pm_state); - state->pm_state = pm_state; + + if (state->pm_state != pm_state) { + if (port->ops->pm) + port->ops->pm(port, pm_state, state->pm_state); + state->pm_state = pm_state; + } } int uart_suspend_port(struct uart_driver *drv, struct uart_port *port) @@ -2085,45 +2087,6 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, } } -/* - * This reverses the effects of uart_configure_port, hanging up the - * port before removal. - */ -static void -uart_unconfigure_port(struct uart_driver *drv, struct uart_state *state) -{ - struct uart_port *port = state->port; - struct uart_info *info = state->info; - - if (info && info->tty) - tty_vhangup(info->tty); - - mutex_lock(&state->mutex); - - state->info = NULL; - - /* - * Free the port IO and memory resources, if any. - */ - if (port->type != PORT_UNKNOWN) - port->ops->release_port(port); - - /* - * Indicate that there isn't a port here anymore. - */ - port->type = PORT_UNKNOWN; - - /* - * Kill the tasklet, and free resources. - */ - if (info) { - tasklet_kill(&info->tlet); - kfree(info); - } - - mutex_unlock(&state->mutex); -} - static struct tty_operations uart_ops = { .open = uart_open, .close = uart_close, @@ -2189,7 +2152,6 @@ int uart_register_driver(struct uart_driver *drv) normal->owner = drv->owner; normal->driver_name = drv->driver_name; - normal->devfs_name = drv->devfs_name; normal->name = drv->dev_name; normal->major = drv->major; normal->minor_start = drv->minor; @@ -2197,7 +2159,7 @@ int uart_register_driver(struct uart_driver *drv) normal->subtype = SERIAL_TYPE_NORMAL; normal->init_termios = tty_std_termios; normal->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; - normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS; + normal->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; normal->driver_state = drv; tty_set_operations(normal, &uart_ops); @@ -2270,6 +2232,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port) state = drv->state + port->line; mutex_lock(&port_mutex); + mutex_lock(&state->mutex); if (state->port) { ret = -EINVAL; goto out; @@ -2304,7 +2267,13 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port) port->cons && !(port->cons->flags & CON_ENABLED)) register_console(port->cons); + /* + * Ensure UPF_DEAD is not set. + */ + port->flags &= ~UPF_DEAD; + out: + mutex_unlock(&state->mutex); mutex_unlock(&port_mutex); return ret; @@ -2322,6 +2291,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port) int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port) { struct uart_state *state = drv->state + port->line; + struct uart_info *info; BUG_ON(in_interrupt()); @@ -2332,11 +2302,48 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port) mutex_lock(&port_mutex); /* - * Remove the devices from devfs + * Mark the port "dead" - this prevents any opens from + * succeeding while we shut down the port. + */ + mutex_lock(&state->mutex); + port->flags |= UPF_DEAD; + mutex_unlock(&state->mutex); + + /* + * Remove the devices from the tty layer */ tty_unregister_device(drv->tty_driver, port->line); - uart_unconfigure_port(drv, state); + info = state->info; + if (info && info->tty) + tty_vhangup(info->tty); + + /* + * All users of this port should now be disconnected from + * this driver, and the port shut down. We should be the + * only thread fiddling with this port from now on. + */ + state->info = NULL; + + /* + * Free the port IO and memory resources, if any. + */ + if (port->type != PORT_UNKNOWN) + port->ops->release_port(port); + + /* + * Indicate that there isn't a port here anymore. + */ + port->type = PORT_UNKNOWN; + + /* + * Kill the tasklet, and free resources. + */ + if (info) { + tasklet_kill(&info->tlet); + kfree(info); + } + state->port = NULL; mutex_unlock(&port_mutex);