From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: [PATCH] tty/serial: atmel: fix TX path in atmel_console_write() Date: Mon, 20 Mar 2017 16:38:57 +0100 Message-ID: <20170320153857.28933-1-nicolas.ferre@microchip.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Sender: stable-owner@vger.kernel.org To: Greg Kroah-Hartman , linux-serial@vger.kernel.org Cc: Richard Genoud , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Nicolas Ferre , "stable #4 . 4+" List-Id: linux-serial@vger.kernel.org A side effect of 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx") is that the console can be called with TX path disabled. Then the system would hang trying to push charecters out in atmel_console_putchar(). Signed-off-by: Nicolas Ferre Fixes: 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx") Cc: stable #4.4+ Acked-by: Richard Genoud --- Hi, I resend this patch removing the "RFC" tag and adding the Acked-by: Richard. Best regards, drivers/tty/serial/atmel_serial.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index d9c05e05d896..2a03ad99d219 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -2486,6 +2486,9 @@ static void atmel_console_write(struct console *co, const char *s, u_int count) pdc_tx = atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN; atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); + /* Make sure that tx path is actually able to send characters */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN); + uart_console_write(port, s, count, atmel_console_putchar); /* -- 2.9.0