1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index f84982e508c7..0422c0f1f852 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1523,9 +1523,8 @@ static struct uart_state *uart_get(struct uart_driver *drv, int line)
         }
 
         if (!state->info) {
-                state->info = kmalloc(sizeof(struct uart_info), GFP_KERNEL);
+                state->info = kzalloc(sizeof(struct uart_info), GFP_KERNEL);
                 if (state->info) {
-                        memset(state->info, 0, sizeof(struct uart_info));
                         init_waitqueue_head(&state->info->open_wait);
                         init_waitqueue_head(&state->info->delta_msr_wait);
 
@@ -1660,6 +1659,7 @@ static const char *uart_type(struct uart_port *port)
 static int uart_line_info(char *buf, struct uart_driver *drv, int i)
 {
         struct uart_state *state = drv->state + i;
+        int pm_state;
         struct uart_port *port = state->port;
         char stat_buf[32];
         unsigned int status;
@@ -1682,9 +1682,16 @@ static int uart_line_info(char *buf, struct uart_driver *drv, int i)
 
         if(capable(CAP_SYS_ADMIN))
         {
+                mutex_lock(&state->mutex);
+                pm_state = state->pm_state;
+                if (pm_state)
+                        uart_change_pm(state, 0);
                 spin_lock_irq(&port->lock);
                 status = port->ops->get_mctrl(port);
                 spin_unlock_irq(&port->lock);
+                if (pm_state)
+                        uart_change_pm(state, pm_state);
+                mutex_unlock(&state->mutex);
 
                 ret += sprintf(buf + ret, " tx:%d rx:%d",
                                 port->icount.tx, port->icount.rx);
@@ -2100,6 +2107,9 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 
                 uart_report_port(drv, port);
 
+                /* Power up port for set_mctrl() */
+                uart_change_pm(state, 0);
+
                 /*
                  * Ensure that the modem control lines are de-activated.
                  * We probably don't need a spinlock around this, but
@@ -2167,13 +2177,11 @@ int uart_register_driver(struct uart_driver *drv)
          * Maybe we should be using a slab cache for this, especially if
          * we have a large number of ports to handle.
          */
-        drv->state = kmalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL);
+        drv->state = kzalloc(sizeof(struct uart_state) * drv->nr, GFP_KERNEL);
         retval = -ENOMEM;
         if (!drv->state)
                 goto out;
 
-        memset(drv->state, 0, sizeof(struct uart_state) * drv->nr);
-
         normal  = alloc_tty_driver(drv->nr);
         if (!normal)
                 goto out;