1 files changed, 22 insertions, 13 deletions

diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index aba1e59f4a88..ac8599a76820 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -317,8 +317,7 @@ struct slgt_info {
         unsigned char *tx_buf;
         int tx_count;
 
-        char flag_buf[MAX_ASYNC_BUFFER_SIZE];
-        char char_buf[MAX_ASYNC_BUFFER_SIZE];
+        char *flag_buf;
         bool drop_rts_on_tx_done;
         struct  _input_signal_events    input_signal_events;
 
@@ -683,7 +682,7 @@ static int open(struct tty_struct *tty, struct file *filp)
         }
 
         mutex_lock(&info->port.mutex);
-        info->port.tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+        info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
         spin_lock_irqsave(&info->netlock, flags);
         if (info->netcount) {
@@ -1855,7 +1854,6 @@ static void hdlcdev_exit(struct slgt_info *info)
  */
 static void rx_async(struct slgt_info *info)
 {
-        struct tty_struct *tty = info->port.tty;
         struct mgsl_icount *icount = &info->icount;
         unsigned int start, end;
         unsigned char *p;
@@ -1894,10 +1892,8 @@ static void rx_async(struct slgt_info *info)
                                 else if (status & BIT0)
                                         stat = TTY_FRAME;
                         }
-                        if (tty) {
-                                tty_insert_flip_char(tty, ch, stat);
-                                chars++;
-                        }
+                        tty_insert_flip_char(&info->port, ch, stat);
+                        chars++;
                 }
 
                 if (i < count) {
@@ -1918,8 +1914,8 @@ static void rx_async(struct slgt_info *info)
                         break;
         }
 
-        if (tty && chars)
-                tty_flip_buffer_push(tty);
+        if (chars)
+                tty_flip_buffer_push(&info->port);
 }
 
 /*
@@ -1961,8 +1957,6 @@ static void bh_handler(struct work_struct *work)
         struct slgt_info *info = container_of(work, struct slgt_info, task);
         int action;
 
-        if (!info)
-                return;
         info->bh_running = true;
 
         while((action = bh_action(info))) {
@@ -2183,7 +2177,7 @@ static void isr_serial(struct slgt_info *info)
                         if (info->port.tty) {
                                 if (!(status & info->ignore_status_mask)) {
                                         if (info->read_status_mask & MASK_BREAK) {
-                                                tty_insert_flip_char(info->port.tty, 0, TTY_BREAK);
+                                                tty_insert_flip_char(&info->port, 0, TTY_BREAK);
                                                 if (info->port.flags & ASYNC_SAK)
                                                         do_SAK(info->port.tty);
                                         }
@@ -3355,11 +3349,24 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
         return retval;
 }
 
+/*
+ * allocate buffers used for calling line discipline receive_buf
+ * directly in synchronous mode
+ * note: add 5 bytes to max frame size to allow appending
+ * 32-bit CRC and status byte when configured to do so
+ */
 static int alloc_tmp_rbuf(struct slgt_info *info)
 {
         info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
         if (info->tmp_rbuf == NULL)
                 return -ENOMEM;
+        /* unused flag buffer to satisfy receive_buf calling interface */
+        info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
+        if (!info->flag_buf) {
+                kfree(info->tmp_rbuf);
+                info->tmp_rbuf = NULL;
+                return -ENOMEM;
+        }
         return 0;
 }
 
@@ -3367,6 +3374,8 @@ static void free_tmp_rbuf(struct slgt_info *info)
 {
         kfree(info->tmp_rbuf);
         info->tmp_rbuf = NULL;
+        kfree(info->flag_buf);
+        info->flag_buf = NULL;
 }
 
 /*