serial: tegra: report error to upper tty layer

Report overrun/parity/frame/break errors to top tty layer. Add support
to ignore break character if IGNBRK is set.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-5-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 4cd6d5f..c3f9913 100644 (file)
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -373,13 +373,21 @@ static char tegra_uart_decode_rx_error(struct tegra_uart_port *tup,
                        tup->uport.icount.frame++;
                        dev_err(tup->uport.dev, "Got frame errors\n");
                } else if (lsr & UART_LSR_BI) {
-                       dev_err(tup->uport.dev, "Got Break\n");
-                       tup->uport.icount.brk++;
-                       /* If FIFO read error without any data, reset Rx FIFO */
+                       /*
+                        * Break error
+                        * If FIFO read error without any data, reset Rx FIFO
+                        */
                        if (!(lsr & UART_LSR_DR) && (lsr & UART_LSR_FIFOE))
                                tegra_uart_fifo_reset(tup, UART_FCR_CLEAR_RCVR);
+                       if (tup->uport.ignore_status_mask & UART_LSR_BI)
+                               return TTY_BREAK;
+                       flag = TTY_BREAK;
+                       tup->uport.icount.brk++;
+                       dev_dbg(tup->uport.dev, "Got Break\n");
                }
+               uart_insert_char(&tup->uport, lsr, UART_LSR_OE, 0, flag);
        }
+
        return flag;
 }
 
@@ -561,6 +569,9 @@ static void tegra_uart_handle_rx_pio(struct tegra_uart_port *tup,
                        break;
 
                flag = tegra_uart_decode_rx_error(tup, lsr);
+               if (flag != TTY_NORMAL)
+                       continue;
+
                ch = (unsigned char) tegra_uart_read(tup, UART_RX);
                tup->uport.icount.rx++;
 
@@ -1223,6 +1234,8 @@ static void tegra_uart_set_termios(struct uart_port *u,
        /* Ignore all characters if CREAD is not set */
        if ((termios->c_cflag & CREAD) == 0)
                tup->uport.ignore_status_mask |= UART_LSR_DR;
+       if (termios->c_iflag & IGNBRK)
+               tup->uport.ignore_status_mask |= UART_LSR_BI;
 
        spin_unlock_irqrestore(&u->lock, flags);
 }