TTY: switch tty_flip_buffer_push

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 12 insertions, 15 deletions

diff --git a/drivers/tty/serial/sc26xx.c b/drivers/tty/serial/sc26xx.c
index 0cd0e4ac12a6..c9735680762d 100644
--- a/drivers/tty/serial/sc26xx.c
+++ b/drivers/tty/serial/sc26xx.c
@@ -136,20 +136,17 @@ static void sc26xx_disable_irq(struct uart_port *port, int mask)
         WRITE_SC(port, IMR, up->imr);
 }
 
-static struct tty_struct *receive_chars(struct uart_port *port)
+static bool receive_chars(struct uart_port *port)
 {
         struct tty_port *tport = NULL;
-        struct tty_struct *tty = NULL;
         int limit = 10000;
         unsigned char ch;
         char flag;
         u8 status;
 
         /* FIXME what is this trying to achieve? */
-        if (port->state != NULL) {              /* Unopened serial console */
+        if (port->state != NULL)                /* Unopened serial console */
                 tport = &port->state->port;
-                tty = tport->tty;
-        }
 
         while (limit-- > 0) {
                 status = READ_SC_PORT(port, SR);
@@ -191,7 +188,7 @@ static struct tty_struct *receive_chars(struct uart_port *port)
 
                 tty_insert_flip_char(tport, ch, flag);
         }
-        return tty;
+        return !!tport;
 }
 
 static void transmit_chars(struct uart_port *port)
@@ -221,36 +218,36 @@ static void transmit_chars(struct uart_port *port)
 static irqreturn_t sc26xx_interrupt(int irq, void *dev_id)
 {
         struct uart_sc26xx_port *up = dev_id;
-        struct tty_struct *tty;
         unsigned long flags;
+        bool push;
         u8 isr;
 
         spin_lock_irqsave(&up->port[0].lock, flags);
 
-        tty = NULL;
+        push = false;
         isr = READ_SC(&up->port[0], ISR);
         if (isr & ISR_TXRDYA)
             transmit_chars(&up->port[0]);
         if (isr & ISR_RXRDYA)
-            tty = receive_chars(&up->port[0]);
+            push = receive_chars(&up->port[0]);
 
         spin_unlock(&up->port[0].lock);
 
-        if (tty)
-                tty_flip_buffer_push(tty);
+        if (push)
+                tty_flip_buffer_push(&up->port[0].state->port);
 
         spin_lock(&up->port[1].lock);
 
-        tty = NULL;
+        push = false;
         if (isr & ISR_TXRDYB)
             transmit_chars(&up->port[1]);
         if (isr & ISR_RXRDYB)
-            tty = receive_chars(&up->port[1]);
+            push = receive_chars(&up->port[1]);
 
         spin_unlock_irqrestore(&up->port[1].lock, flags);
 
-        if (tty)
-                tty_flip_buffer_push(tty);
+        if (push)
+                tty_flip_buffer_push(&up->port[1].state->port);
 
         return IRQ_HANDLED;
 }