MLK-13710 tty: serial: fsl_lpuart: add magic SysRq support

Add magic SysRq key support.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 88c2b71..c024eb3 100644 (file)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -651,8 +651,14 @@ static irqreturn_t lpuart32_rxint(int irq, void *dev_id)
                 */
                sr = lpuart32_read(sport->port.membase + UARTSTAT);
                rx = lpuart32_read(sport->port.membase + UARTDATA);
-               rx &= 0x3ff;
 
+               if ((sr & UARTSTAT_FE) && (rx & UARTDATA_FRETSC) &&
+                       !(rx & UARTDATA_MASK)) {
+                       if (uart_handle_break(&sport->port))
+                               continue;
+               }
+
+               rx &= UARTDATA_MASK;
                if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
                        continue;