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) <hpeter+linux_kernel@gmail.com>
[ johan: fix corrupt line settings on break due to missing shadow_lcr
  update in set_termios() ]
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Ji-Ze Hong (Peter Hong) 2019-04-30 09:22:32 +08:00 committed by Johan Hovold
parent 268ddb5e9b
commit 7f6fc50242
1 changed files with 25 additions and 6 deletions

View File

@ -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)