serial: fsl_lpuart: don't modify arbitrary data on lpuart32

[ Upstream commit ccf08fd1204bcb5311cc10aea037c71c6e74720a ]

lpuart_rx_dma_startup() is used for both the 8 bit and the 32 bit
version of the LPUART. Modify the UARTCR only for the 8 bit version.

Fixes: f4eef224a09f ("serial: fsl_lpuart: add sysrq support when using dma")
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20210512141255.18277-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index bd047e1..6b8e638 100644 (file)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1625,7 +1625,7 @@ static void lpuart_rx_dma_startup(struct lpuart_port *sport)
        sport->lpuart_dma_rx_use = true;
        rx_dma_timer_init(sport);
 
-       if (sport->port.has_sysrq) {
+       if (sport->port.has_sysrq && !lpuart_is_32(sport)) {
                cr3 = readb(sport->port.membase + UARTCR3);
                cr3 |= UARTCR3_FEIE;
                writeb(cr3, sport->port.membase + UARTCR3);