target/linux/layerscape/patches-5.4/819-uart-0002-tty-serial-fsl_lpuart-add-modem-device-reset.patch

   1 From 5b05462e88dc87d83566d04dd196b4f3d9dc0eef Mon Sep 17 00:00:00 2001
   2 From: Fugang Duan <fugang.duan@nxp.com>
   3 Date: Mon, 28 Jan 2019 10:12:52 +0800
   4 Subject: [PATCH] tty: serial: fsl_lpuart: add modem device reset
   5
   6 Add modem device reset, wthether to reset depend on dts configuration.
   7
   8 Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
   9 ---
  10  drivers/tty/serial/fsl_lpuart.c | 10 ++++++++++
  11  1 file changed, 10 insertions(+)
  12
  13 --- a/drivers/tty/serial/fsl_lpuart.c
  14 +++ b/drivers/tty/serial/fsl_lpuart.c
  15 @@ -22,6 +22,7 @@
  16  #include <linux/of_dma.h>
  17  #include <linux/pm_domain.h>
  18  #include <linux/pm_runtime.h>
  19 +#include <linux/reset.h>
  20  #include <linux/serial_core.h>
  21  #include <linux/slab.h>
  22  #include <linux/tty_flip.h>
  23 @@ -1544,8 +1545,17 @@ static void lpuart32_configure(struct lp
  24  static int lpuart32_startup(struct uart_port *port)
  25  {
  26         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
  27 +       struct tty_port *tty_port = &sport->port.state->port;
  28         unsigned long flags;
  29         unsigned long temp;
  30 +       int ret;
  31 +
  32 +       /* some modem may need reset */
  33 +       if (!tty_port_suspended(tty_port)) {
  34 +               ret = device_reset(sport->port.dev);
  35 +               if (ret && ret != -ENOENT)
  36 +                       return ret;
  37 +       }
  38
  39         /* determine FIFO size */
  40         temp = lpuart32_read(&sport->port, UARTFIFO);