[PATCH V2 04/12] serial: tegra: report error to upper tty layer

From: Krishna Yarlagadda
Date: Wed Sep 04 2019 - 00:43:34 EST


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@xxxxxxxxxx>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx>
---
drivers/tty/serial/serial-tegra.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 4cd6d5f..c3f9913 100644
--- 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);
}
--
2.7.4