From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754873AbdCTPig (ORCPT ); Mon, 20 Mar 2017 11:38:36 -0400 Received: from esa4.microchip.iphmx.com ([68.232.154.123]:13246 "EHLO esa4.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754365AbdCTPi2 (ORCPT ); Mon, 20 Mar 2017 11:38:28 -0400 X-IronPort-AV: E=Sophos;i="5.36,194,1486450800"; d="scan'208";a="310982" From: Nicolas Ferre To: Greg Kroah-Hartman , CC: Richard Genoud , , , Nicolas Ferre , "stable #4 . 4+" 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> X-Mailer: git-send-email 2.9.0 MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@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