From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: Andy Gross <andy.gross@linaro.org>,
Stephen Boyd <sboyd@codeaurora.org>,
David Brown <david.brown@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.com>,
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 [thread overview]
Message-ID: <1465844571-1229-1-git-send-email-bjorn.andersson@linaro.org> (raw)
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 <sboyd@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---
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
next reply other threads:[~2016-06-13 19:03 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-13 19:02 Bjorn Andersson [this message]
2016-06-15 12:58 ` [RFC PATCH] tty: serial: msm_serial: Don't reset uart on set_termios Pramod Gurav
2016-06-16 1:11 ` Stephen Boyd
2016-06-16 18:24 ` [PATCH v2] tty: serial: msm: Don't reconfigure same baud rate Bjorn Andersson
2016-06-17 10:02 ` Nicolas Dechesne
2016-06-21 9:43 ` Nicolas Dechesne
2016-06-22 9:59 ` Srinivas Kandagatla
2016-06-20 23:54 ` Stephen Boyd
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