When the tty layer requests the uart to throttle, the current code
executing in msm_serial will trigger "Bad mode in Error Handler" and
generate an invalid stack frame in pstore before rebooting (that is if
pstore is indeed configured: otherwise the user shall just notice a
reboot with no further information dumped to the console).

This patch replaces the PIO byte accessor with the word accessor
already used in PIO mode.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-or...@linaro.org>
---
 drivers/tty/serial/msm_serial.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index 109096033bb1..23833ad952ba 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -860,6 +860,7 @@ static void msm_handle_tx(struct uart_port *port)
        struct circ_buf *xmit = &msm_port->uart.state->xmit;
        struct msm_dma *dma = &msm_port->tx_dma;
        unsigned int pio_count, dma_count, dma_min;
+       char buf[4] = { 0 };
        void __iomem *tf;
        int err = 0;
 
@@ -869,10 +870,12 @@ static void msm_handle_tx(struct uart_port *port)
                else
                        tf = port->membase + UART_TF;
 
+               buf[0] = port->x_char;
+
                if (msm_port->is_uartdm)
                        msm_reset_dm_count(port, 1);
 
-               iowrite8_rep(tf, &port->x_char, 1);
+               iowrite32_rep(tf, buf, 1);
                port->icount.tx++;
                port->x_char = 0;
                return;
-- 
2.21.0

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