Commit 8bb4ca6b authored by Peter Hung's avatar Peter Hung Committed by Johan Hovold
Browse files

USB: f81232: implement set_termios() 



The original driver had do not any h/w change in driver.
This patch implements with configure H/W for
baud/parity/word length/stop bits functional in f81232_set_termios().

This patch also implement DTR/RTS control when baudrate B0.
We drop DTR/RTS when B0, otherwise enable it.

We are checking baudrate in set_termios() too, If baudrate larger then 115200,
it will be changed to 115200 and use tty_encode_baud_rate() to encode into tty

Signed-off-by: default avatarPeter Hung <hpeter+linux_kernel@gmail.com>
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
parent 94f87309

drivers/usb/serial/f81232.c

+108 −4
Original line number Diff line number Diff line
@@ -31,14 +31,19 @@ static const struct usb_device_id id_table[] = { 
};

MODULE_DEVICE_TABLE(usb, id_table);



/* Maximum baudrate for F81232 */

#define F81232_MAX_BAUDRATE	115200



/* USB Control EP parameter */

#define F81232_REGISTER_REQUEST	0xa0

#define F81232_GET_REGISTER		0xc0

#define F81232_SET_REGISTER		0x40



#define SERIAL_BASE_ADDRESS			0x0120

#define RECEIVE_BUFFER_REGISTER		(0x00 + SERIAL_BASE_ADDRESS)

#define INTERRUPT_ENABLE_REGISTER	(0x01 + SERIAL_BASE_ADDRESS)

#define FIFO_CONTROL_REGISTER		(0x02 + SERIAL_BASE_ADDRESS)

#define LINE_CONTROL_REGISTER		(0x03 + SERIAL_BASE_ADDRESS)

#define MODEM_CONTROL_REGISTER		(0x04 + SERIAL_BASE_ADDRESS)

#define MODEM_STATUS_REGISTER		(0x06 + SERIAL_BASE_ADDRESS)
@@ -64,6 +69,11 @@ struct f81232_private { 
	struct usb_serial_port *port;

};



static int calc_baud_divisor(speed_t baudrate)

{

	return DIV_ROUND_CLOSEST(F81232_MAX_BAUDRATE, baudrate);

}



static int f81232_get_register(struct usb_serial_port *port, u16 reg, u8 *val)

{

	int status;
@@ -350,6 +360,53 @@ static void f81232_break_ctl(struct tty_struct *tty, int break_state) 
	 */

}



static void f81232_set_baudrate(struct usb_serial_port *port, speed_t baudrate)

{

	u8 lcr;

	int divisor, status = 0;



	divisor = calc_baud_divisor(baudrate);



	status = f81232_get_register(port, LINE_CONTROL_REGISTER,

			 &lcr); /* get LCR */

	if (status) {

		dev_err(&port->dev, "%s failed to get LCR: %d\n",

			__func__, status);

		return;

	}



	status = f81232_set_register(port, LINE_CONTROL_REGISTER,

			 lcr | UART_LCR_DLAB); /* Enable DLAB */

	if (status) {

		dev_err(&port->dev, "%s failed to set DLAB: %d\n",

			__func__, status);

		return;

	}



	status = f81232_set_register(port, RECEIVE_BUFFER_REGISTER,

			 divisor & 0x00ff); /* low */

	if (status) {

		dev_err(&port->dev, "%s failed to set baudrate MSB: %d\n",

			__func__, status);

		goto reapply_lcr;

	}



	status = f81232_set_register(port, INTERRUPT_ENABLE_REGISTER,

			 (divisor & 0xff00) >> 8); /* high */

	if (status) {

		dev_err(&port->dev, "%s failed to set baudrate LSB: %d\n",

			__func__, status);

	}



reapply_lcr:

	status = f81232_set_register(port, LINE_CONTROL_REGISTER,

			lcr & ~UART_LCR_DLAB);

	if (status) {

		dev_err(&port->dev, "%s failed to set DLAB: %d\n",

			__func__, status);

	}

}



static int f81232_port_enable(struct usb_serial_port *port)

{

	u8 val;
@@ -395,15 +452,62 @@ 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)

{

	/* FIXME - Stubbed out for now */

	u8 new_lcr = 0;

	int status = 0;

	speed_t baudrate;



	/* Don't change anything if nothing has changed */

	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))

		return;



	/* Do the real work here... */

	if (old_termios)

		tty_termios_copy_hw(&tty->termios, old_termios);

	if (C_BAUD(tty) == B0)

		f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);

	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)

		f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);



	baudrate = tty_get_baud_rate(tty);

	if (baudrate > 0) {

		if (baudrate > F81232_MAX_BAUDRATE) {

			baudrate = F81232_MAX_BAUDRATE;

			tty_encode_baud_rate(tty, baudrate, baudrate);

		}

		f81232_set_baudrate(port, baudrate);

	}



	if (C_PARENB(tty)) {

		new_lcr |= UART_LCR_PARITY;



		if (!C_PARODD(tty))

			new_lcr |= UART_LCR_EPAR;



		if (C_CMSPAR(tty))

			new_lcr |= UART_LCR_SPAR;

	}



	if (C_CSTOPB(tty))

		new_lcr |= UART_LCR_STOP;



	switch (C_CSIZE(tty)) {

	case CS5:

		new_lcr |= UART_LCR_WLEN5;

		break;

	case CS6:

		new_lcr |= UART_LCR_WLEN6;

		break;

	case CS7:

		new_lcr |= UART_LCR_WLEN7;

		break;

	default:

	case CS8:

		new_lcr |= UART_LCR_WLEN8;

		break;

	}



	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);

	}

}



static int f81232_tiocmget(struct tty_struct *tty)

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