Merge tag 'tty-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are two small tty/serial fixes for 5.16-rc6.  They include:

   - n_hdlc fix for syzbot reported problem that you were previously
     copied on.

   - 8250_fintek driver fix that resolved a console problem by removing
     a previous change.

  Both have been in linux-next with no reported issues"

* tag 'tty-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_fintek: Fix garbled text for console
  tty: n_hdlc: make n_hdlc_tty_wakeup() asynchronous

2 files changed, 22 insertions, 21 deletions

diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 7e0884ecc74f..23ba1fc99df8 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -140,6 +140,8 @@ struct n_hdlc {
 	struct n_hdlc_buf_list	rx_buf_list;
 	struct n_hdlc_buf_list	tx_free_buf_list;
 	struct n_hdlc_buf_list	rx_free_buf_list;
+	struct work_struct	write_work;
+	struct tty_struct	*tty_for_write_work;
 };
 
 /*
@@ -154,6 +156,7 @@ static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *list);
 /* Local functions */
 
 static struct n_hdlc *n_hdlc_alloc(void);
+static void n_hdlc_tty_write_work(struct work_struct *work);
 
 /* max frame size for memory allocations */
 static int maxframe = 4096;
@@ -210,6 +213,8 @@ static void n_hdlc_tty_close(struct tty_struct *tty)
 	wake_up_interruptible(&tty->read_wait);
 	wake_up_interruptible(&tty->write_wait);
 
+	cancel_work_sync(&n_hdlc->write_work);
+
 	n_hdlc_free_buf_list(&n_hdlc->rx_free_buf_list);
 	n_hdlc_free_buf_list(&n_hdlc->tx_free_buf_list);
 	n_hdlc_free_buf_list(&n_hdlc->rx_buf_list);
@@ -241,6 +246,8 @@ static int n_hdlc_tty_open(struct tty_struct *tty)
 		return -ENFILE;
 	}
 
+	INIT_WORK(&n_hdlc->write_work, n_hdlc_tty_write_work);
+	n_hdlc->tty_for_write_work = tty;
 	tty->disc_data = n_hdlc;
 	tty->receive_room = 65536;
 
@@ -335,6 +342,20 @@ check_again:
 }	/* end of n_hdlc_send_frames() */
 
 /**
+ * n_hdlc_tty_write_work - Asynchronous callback for transmit wakeup
+ * @work: pointer to work_struct
+ *
+ * Called when low level device driver can accept more send data.
+ */
+static void n_hdlc_tty_write_work(struct work_struct *work)
+{
+	struct n_hdlc *n_hdlc = container_of(work, struct n_hdlc, write_work);
+	struct tty_struct *tty = n_hdlc->tty_for_write_work;
+
+	n_hdlc_send_frames(n_hdlc, tty);
+}	/* end of n_hdlc_tty_write_work() */
+
+/**
  * n_hdlc_tty_wakeup - Callback for transmit wakeup
  * @tty: pointer to associated tty instance data
  *
@@ -344,7 +365,7 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty)
 {
 	struct n_hdlc *n_hdlc = tty->disc_data;
 
-	n_hdlc_send_frames(n_hdlc, tty);
+	schedule_work(&n_hdlc->write_work);
 }	/* end of n_hdlc_tty_wakeup() */
 
 /**
diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index 31c9e83ea3cb..251f0018ae8c 100644
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -290,25 +290,6 @@ static void fintek_8250_set_max_fifo(struct fintek_8250 *pdata)
 	}
 }
 
-static void fintek_8250_goto_highspeed(struct uart_8250_port *uart,
-			      struct fintek_8250 *pdata)
-{
-	sio_write_reg(pdata, LDN, pdata->index);
-
-	switch (pdata->pid) {
-	case CHIP_ID_F81966:
-	case CHIP_ID_F81866: /* set uart clock for high speed serial mode */
-		sio_write_mask_reg(pdata, F81866_UART_CLK,
-			F81866_UART_CLK_MASK,
-			F81866_UART_CLK_14_769MHZ);
-
-		uart->port.uartclk = 921600 * 16;
-		break;
-	default: /* leave clock speed untouched */
-		break;
-	}
-}
-
 static void fintek_8250_set_termios(struct uart_port *port,
 				    struct ktermios *termios,
 				    struct ktermios *old)
@@ -430,7 +411,6 @@ static int probe_setup_port(struct fintek_8250 *pdata,
 
 				fintek_8250_set_irq_mode(pdata, level_mode);
 				fintek_8250_set_max_fifo(pdata);
-				fintek_8250_goto_highspeed(uart, pdata);
 
 				fintek_8250_exit_key(addr[i]);