From 7f6fc50242d11d4fedab9cf6c5e8af368c076ccd Mon Sep 17 00:00:00 2001 From: "Ji-Ze Hong (Peter Hong)" Date: Tue, 30 Apr 2019 09:22:32 +0800 Subject: [PATCH] USB: serial: f81232: implement break control Implement Fintek F81232 break on/off with LCR register. It's the same with 16550A LCR register layout. Signed-off-by: Ji-Ze Hong (Peter Hong) [ johan: fix corrupt line settings on break due to missing shadow_lcr update in set_termios() ] Signed-off-by: Johan Hovold --- drivers/usb/serial/f81232.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c index 4f65ddd65cab..43fa1f0716b7 100644 --- a/drivers/usb/serial/f81232.c +++ b/drivers/usb/serial/f81232.c @@ -65,6 +65,7 @@ struct f81232_private { struct mutex lock; u8 modem_control; u8 modem_status; + u8 shadow_lcr; speed_t baud_base; struct work_struct lsr_work; struct work_struct interrupt_work; @@ -377,13 +378,23 @@ static void f81232_process_read_urb(struct urb *urb) static void f81232_break_ctl(struct tty_struct *tty, int break_state) { - /* FIXME - Stubbed out for now */ + struct usb_serial_port *port = tty->driver_data; + struct f81232_private *priv = usb_get_serial_port_data(port); + int status; - /* - * break_state = -1 to turn on break, and 0 to turn off break - * see drivers/char/tty_io.c to see it used. - * last_set_data_urb_value NEVER has the break bit set in it. - */ + mutex_lock(&priv->lock); + + if (break_state) + priv->shadow_lcr |= UART_LCR_SBC; + else + priv->shadow_lcr &= ~UART_LCR_SBC; + + status = f81232_set_register(port, LINE_CONTROL_REGISTER, + priv->shadow_lcr); + if (status) + dev_err(&port->dev, "set break failed: %d\n", status); + + mutex_unlock(&priv->lock); } static int f81232_find_clk(speed_t baudrate) @@ -519,6 +530,7 @@ static int f81232_port_disable(struct usb_serial_port *port) static void f81232_set_termios(struct tty_struct *tty, struct usb_serial_port *port, struct ktermios *old_termios) { + struct f81232_private *priv = usb_get_serial_port_data(port); u8 new_lcr = 0; int status = 0; speed_t baudrate; @@ -572,11 +584,18 @@ static void f81232_set_termios(struct tty_struct *tty, break; } + mutex_lock(&priv->lock); + + new_lcr |= (priv->shadow_lcr & UART_LCR_SBC); status = f81232_set_register(port, LINE_CONTROL_REGISTER, new_lcr); if (status) { dev_err(&port->dev, "%s failed to set LCR: %d\n", __func__, status); } + + priv->shadow_lcr = new_lcr; + + mutex_unlock(&priv->lock); } static int f81232_tiocmget(struct tty_struct *tty)