Merge tag 'tty-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty and serial driver fixes from Greg KH:
 "Here are some TTY and Serial driver fixes for 5.19-rc7. They resolve a
  number of reported problems including:

   - longtime bug in pty_write() that has been reported in the past.

   - 8250 driver fixes

   - new serial device ids

   - vt overlapping data copy bugfix

   - other tiny serial driver bugfixes

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'tty-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: use new tty_insert_flip_string_and_push_buffer() in pty_write()
  tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()
  serial: 8250: dw: Fix the macro RZN1_UART_xDMACR_8_WORD_BURST
  vt: fix memory overlapping when deleting chars in the buffer
  serial: mvebu-uart: correctly report configured baudrate value
  serial: 8250: Fix PM usage_count for console handover
  serial: 8250: fix return error code in serial8250_request_std_resource()
  serial: stm32: Clear prev values before setting RTS delays
  tty: Add N_CAN327 line discipline ID for ELM327 based CAN driver
  serial: 8250: Fix __stop_tx() & DMA Tx restart races
  serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle
  tty: serial: samsung_tty: set dma burst_size to 1
  serial: 8250: dw: enable using pdata with ACPI

1 files changed, 2 insertions, 12 deletions

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 74bfabe5b453..752dab3356d7 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -111,21 +111,11 @@ static void pty_unthrottle(struct tty_struct *tty)
 static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
 {
 	struct tty_struct *to = tty->link;
-	unsigned long flags;
 
-	if (tty->flow.stopped)
+	if (tty->flow.stopped || !c)
 		return 0;
 
-	if (c > 0) {
-		spin_lock_irqsave(&to->port->lock, flags);
-		/* Stuff the data into the input queue of the other end */
-		c = tty_insert_flip_string(to->port, buf, c);
-		spin_unlock_irqrestore(&to->port->lock, flags);
-		/* And shovel */
-		if (c)
-			tty_flip_buffer_push(to->port);
-	}
-	return c;
+	return tty_insert_flip_string_and_push_buffer(to->port, buf, c);
 }
 
 /**