From a071517b85cc2f33102c61a674de1dc8af79cf34 Mon Sep 17 00:00:00 2001 From: Jorge Ramirez-Ortiz Date: Mon, 20 May 2019 20:38:48 +0200 Subject: [PATCH] tty: serial: msm_serial: Fix XON/XOFF commit 61c0e37950b88bad590056286c1d766b1f167f4e upstream. 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. Fixes: 68252424a7c7 ("tty: serial: msm: Support big-endian CPUs") Cc: stable@vger.kernel.org Signed-off-by: Jorge Ramirez-Ortiz Reviewed-by: Bjorn Andersson Reviewed-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- 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 736b74fd6623..0f41b936da03 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; -- GitLab