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, 41 insertions, 5 deletions

diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index bfa431a8e690..595d8b49c745 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -532,6 +532,15 @@ static void flush_to_ldisc(struct work_struct *work)
 
 }
 
+static inline void tty_flip_buffer_commit(struct tty_buffer *tail)
+{
+	/*
+	 * Paired w/ acquire in flush_to_ldisc(); ensures flush_to_ldisc() sees
+	 * buffer data.
+	 */
+	smp_store_release(&tail->commit, tail->used);
+}
+
 /**
  * tty_flip_buffer_push		-	push terminal buffers
  * @port: tty port to push
@@ -546,16 +555,43 @@ void tty_flip_buffer_push(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
 
-	/*
-	 * Paired w/ acquire in flush_to_ldisc(); ensures flush_to_ldisc() sees
-	 * buffer data.
-	 */
-	smp_store_release(&buf->tail->commit, buf->tail->used);
+	tty_flip_buffer_commit(buf->tail);
 	queue_work(system_unbound_wq, &buf->work);
 }
 EXPORT_SYMBOL(tty_flip_buffer_push);
 
 /**
+ * tty_insert_flip_string_and_push_buffer - add characters to the tty buffer and
+ *	push
+ * @port: tty port
+ * @chars: characters
+ * @size: size
+ *
+ * The function combines tty_insert_flip_string() and tty_flip_buffer_push()
+ * with the exception of properly holding the @port->lock.
+ *
+ * To be used only internally (by pty currently).
+ *
+ * Returns: the number added.
+ */
+int tty_insert_flip_string_and_push_buffer(struct tty_port *port,
+		const unsigned char *chars, size_t size)
+{
+	struct tty_bufhead *buf = &port->buf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	size = tty_insert_flip_string(port, chars, size);
+	if (size)
+		tty_flip_buffer_commit(buf->tail);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	queue_work(system_unbound_wq, &buf->work);
+
+	return size;
+}
+
+/**
  * tty_buffer_init		-	prepare a tty buffer structure
  * @port: tty port to initialise
  *