From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424096AbcFMTDU (ORCPT ); Mon, 13 Jun 2016 15:03:20 -0400 Received: from mail-pf0-f180.google.com ([209.85.192.180]:34447 "EHLO mail-pf0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424055AbcFMTC5 (ORCPT ); Mon, 13 Jun 2016 15:02:57 -0400 From: Bjorn Andersson To: Andy Gross , Stephen Boyd , David Brown Cc: Greg Kroah-Hartman , Jiri Slaby , linux-arm-msm@vger.kernel.org (open list:ARM/QUALCOMM SUPPORT), linux-soc@vger.kernel.org (open list:ARM/QUALCOMM SUPPORT), linux-serial@vger.kernel.org (open list:SERIAL DRIVERS), linux-kernel@vger.kernel.org (open list) Subject: [RFC PATCH] tty: serial: msm_serial: Don't reset uart on set_termios Date: Mon, 13 Jun 2016 12:02:51 -0700 Message-Id: <1465844571-1229-1-git-send-email-bjorn.andersson@linaro.org> X-Mailer: git-send-email 2.5.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Upon opening the tty, uart_open() ends up calling msm_set_baud_rate() which resets the uart block. If this happens as we're coming out of msm_console_write() a full fifo worth of console output will be discarded. Cc: Stephen Boyd Signed-off-by: Bjorn Andersson --- As reported here: https://bugs.96boards.org/show_bug.cgi?id=378 drivers/tty/serial/msm_serial.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c index b7d80bd57db9..93a10ac44933 100644 --- a/drivers/tty/serial/msm_serial.c +++ b/drivers/tty/serial/msm_serial.c @@ -813,23 +813,6 @@ static unsigned int msm_get_mctrl(struct uart_port *port) return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS; } -static void msm_reset(struct uart_port *port) -{ - struct msm_port *msm_port = UART_TO_MSM(port); - - /* reset everything */ - msm_write(port, UART_CR_CMD_RESET_RX, UART_CR); - msm_write(port, UART_CR_CMD_RESET_TX, UART_CR); - msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR); - msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR); - msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR); - msm_write(port, UART_CR_CMD_SET_RFR, UART_CR); - - /* Disable DM modes */ - if (msm_port->is_uartdm) - msm_write(port, 0, UARTDM_DMEN); -} - static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl) { unsigned int mr; @@ -972,7 +955,6 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud, msm_write(port, 10, UART_TFWR); msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR); - msm_reset(port); /* Enable RX and TX */ msm_write(port, UART_CR_TX_ENABLE | UART_CR_RX_ENABLE, UART_CR); -- 2.5.0