From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jorge Ramirez-Ortiz Subject: [PATCH v2] tty: serial: msm_serial: Fix XON/XOFF Date: Mon, 20 May 2019 20:38:48 +0200 Message-ID: <20190520183848.27719-1-jorge.ramirez-ortiz@linaro.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: jorge.ramirez-ortiz@linaro.org, agross@kernel.org, david.brown@linaro.org, gregkh@linuxfoundation.org, sboyd@kernel.org, bjorn.andersson@linaro.org Cc: jslaby@suse.com, keescook@chromium.org, anton@enomsg.org, ccross@android.com, tony.luck@intel.com, linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-serial@vger.kernel.org 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 --- 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