Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753635AbbBTDXr (ORCPT ); Thu, 19 Feb 2015 22:23:47 -0500 Received: from mail-pa0-f53.google.com ([209.85.220.53]:36872 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753100AbbBTDXp (ORCPT ); Thu, 19 Feb 2015 22:23:45 -0500 X-Google-Original-Sender: Date: Fri, 20 Feb 2015 10:25:33 +0700 From: Johan Hovold To: Jari Ruusu Cc: Johan Hovold , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: usb serial: pl2303 driver TxD "break" stays after close() bug Message-ID: <20150220032533.GM12405@localhost> References: <20150219055047.GJ12405@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.22 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2987 Lines: 97 On Thu, Feb 19, 2015 at 03:38:39PM +0200, Jari Ruusu wrote: > On 2/19/15, Johan Hovold wrote: > > What happens when you reopen the port? Is the break state cleared then? > > Stuck "break" signal is not cleared on re-open. > > To clear it, you need to poke it with ioctl(fd, TIOCCBRK, 0) > or disconnect the device. That's definitely a bug. Care to test the patch below? Thanks, Johan >From ee3f2d35adc59822d72f3908078da7f361c26577 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 20 Feb 2015 10:05:51 +0700 Subject: [PATCH] USB: pl2303: disable break on shutdown Currently an enabled break state is not disabled on final close nor on re-open and has to be disabled manually. Fix this by disabling break on port shutdown. Reported-by: Jari Ruusu Signed-off-by: Johan Hovold --- drivers/usb/serial/pl2303.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index 0f872e6b2c87..f6fe4737185d 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -132,6 +132,7 @@ MODULE_DEVICE_TABLE(usb, id_table); #define UART_OVERRUN_ERROR 0x40 #define UART_CTS 0x80 +static void pl2303_set_break(struct usb_serial_port *port, bool enable); enum pl2303_type { TYPE_01, /* Type 0 and 1 (difference unknown) */ @@ -613,6 +614,7 @@ static void pl2303_dtr_rts(struct usb_serial_port *port, int on) static void pl2303_close(struct usb_serial_port *port) { + pl2303_set_break(port, false); usb_serial_generic_close(port); usb_kill_urb(port->interrupt_in_urb); } @@ -741,17 +743,16 @@ static int pl2303_ioctl(struct tty_struct *tty, return -ENOIOCTLCMD; } -static void pl2303_break_ctl(struct tty_struct *tty, int break_state) +static void pl2303_set_break(struct usb_serial_port *port, bool enable) { - struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; u16 state; int result; - if (break_state == 0) - state = BREAK_OFF; - else + if (enable) state = BREAK_ON; + else + state = BREAK_OFF; dev_dbg(&port->dev, "%s - turning break %s\n", __func__, state == BREAK_OFF ? "off" : "on"); @@ -763,6 +764,13 @@ static void pl2303_break_ctl(struct tty_struct *tty, int break_state) dev_err(&port->dev, "error sending break = %d\n", result); } +static void pl2303_break_ctl(struct tty_struct *tty, int state) +{ + struct usb_serial_port *port = tty->driver_data; + + pl2303_set_break(port, state); +} + static void pl2303_update_line_status(struct usb_serial_port *port, unsigned char *data, unsigned int actual_length) -- 2.0.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/