cp2101.c

linux 内核源代码

	switch(bits & BITS_DATA_MASK) {
		case BITS_DATA_5:
			dbg("%s - data bits = 5", __FUNCTION__);
			cflag |= CS5;
			break;
		case BITS_DATA_6:
			dbg("%s - data bits = 6", __FUNCTION__);
			cflag |= CS6;
			break;
		case BITS_DATA_7:
			dbg("%s - data bits = 7", __FUNCTION__);
			cflag |= CS7;
			break;
		case BITS_DATA_8:
			dbg("%s - data bits = 8", __FUNCTION__);
			cflag |= CS8;
			break;
		case BITS_DATA_9:
			dbg("%s - data bits = 9 (not supported, "
					"using 8 data bits)", __FUNCTION__);
			cflag |= CS8;
			bits &= ~BITS_DATA_MASK;
			bits |= BITS_DATA_8;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
		default:
			dbg("%s - Unknown number of data bits, "
					"using 8", __FUNCTION__);
			cflag |= CS8;
			bits &= ~BITS_DATA_MASK;
			bits |= BITS_DATA_8;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
	}

	switch(bits & BITS_PARITY_MASK) {
		case BITS_PARITY_NONE:
			dbg("%s - parity = NONE", __FUNCTION__);
			cflag &= ~PARENB;
			break;
		case BITS_PARITY_ODD:
			dbg("%s - parity = ODD", __FUNCTION__);
			cflag |= (PARENB|PARODD);
			break;
		case BITS_PARITY_EVEN:
			dbg("%s - parity = EVEN", __FUNCTION__);
			cflag &= ~PARODD;
			cflag |= PARENB;
			break;
		case BITS_PARITY_MARK:
			dbg("%s - parity = MARK (not supported, "
					"disabling parity)", __FUNCTION__);
			cflag &= ~PARENB;
			bits &= ~BITS_PARITY_MASK;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
		case BITS_PARITY_SPACE:
			dbg("%s - parity = SPACE (not supported, "
					"disabling parity)", __FUNCTION__);
			cflag &= ~PARENB;
			bits &= ~BITS_PARITY_MASK;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
		default:
			dbg("%s - Unknown parity mode, "
					"disabling parity", __FUNCTION__);
			cflag &= ~PARENB;
			bits &= ~BITS_PARITY_MASK;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
	}

	cflag &= ~CSTOPB;
	switch(bits & BITS_STOP_MASK) {
		case BITS_STOP_1:
			dbg("%s - stop bits = 1", __FUNCTION__);
			break;
		case BITS_STOP_1_5:
			dbg("%s - stop bits = 1.5 (not supported, "
					"using 1 stop bit)", __FUNCTION__);
			bits &= ~BITS_STOP_MASK;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
		case BITS_STOP_2:
			dbg("%s - stop bits = 2", __FUNCTION__);
			cflag |= CSTOPB;
			break;
		default:
			dbg("%s - Unknown number of stop bits, "
					"using 1 stop bit", __FUNCTION__);
			bits &= ~BITS_STOP_MASK;
			cp2101_set_config(port, CP2101_BITS, &bits, 2);
			break;
	}

	cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
	if (modem_ctl[0] & 0x0008) {
		dbg("%s - flow control = CRTSCTS", __FUNCTION__);
		cflag |= CRTSCTS;
	} else {
		dbg("%s - flow control = NONE", __FUNCTION__);
		cflag &= ~CRTSCTS;
	}

	port->tty->termios->c_cflag = cflag;
}

static void cp2101_set_termios (struct usb_serial_port *port,
		struct ktermios *old_termios)
{
	unsigned int cflag, old_cflag;
	int baud=0, bits;
	unsigned int modem_ctl[4];

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (!port->tty || !port->tty->termios) {
		dbg("%s - no tty structures", __FUNCTION__);
		return;
	}
	port->tty->termios->c_cflag &= ~CMSPAR;

	cflag = port->tty->termios->c_cflag;
	old_cflag = old_termios->c_cflag;
	baud = tty_get_baud_rate(port->tty);

	/* If the baud rate is to be updated*/
	if (baud != tty_termios_baud_rate(old_termios)) {
		switch (baud) {
			case 0:
			case 600:
			case 1200:
			case 1800:
			case 2400:
			case 4800:
			case 7200:
			case 9600:
			case 14400:
			case 19200:
			case 28800:
			case 38400:
			case 55854:
			case 57600:
			case 115200:
			case 127117:
			case 230400:
			case 460800:
			case 921600:
			case 3686400:
				break;
			default:
				baud = 9600;
				break;
		}

		if (baud) {
			dbg("%s - Setting baud rate to %d baud", __FUNCTION__,
					baud);
			if (cp2101_set_config_single(port, CP2101_BAUDRATE,
						(BAUD_RATE_GEN_FREQ / baud))) {
				dev_err(&port->dev, "Baud rate requested not "
						"supported by device\n");
				baud = tty_termios_baud_rate(old_termios);
			}
		}
	}
	/* Report back the resulting baud rate */
	tty_encode_baud_rate(port->tty, baud, baud);

	/* If the number of data bits is to be updated */
	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
		cp2101_get_config(port, CP2101_BITS, &bits, 2);
		bits &= ~BITS_DATA_MASK;
		switch (cflag & CSIZE) {
			case CS5:
				bits |= BITS_DATA_5;
				dbg("%s - data bits = 5", __FUNCTION__);
				break;
			case CS6:
				bits |= BITS_DATA_6;
				dbg("%s - data bits = 6", __FUNCTION__);
				break;
			case CS7:
				bits |= BITS_DATA_7;
				dbg("%s - data bits = 7", __FUNCTION__);
				break;
			case CS8:
				bits |= BITS_DATA_8;
				dbg("%s - data bits = 8", __FUNCTION__);
				break;
			/*case CS9:
			 	bits |= BITS_DATA_9;
				dbg("%s - data bits = 9", __FUNCTION__);
				break;*/
			default:
				dev_err(&port->dev, "cp2101 driver does not "
					"support the number of bits requested,"
					" using 8 bit mode\n");
				bits |= BITS_DATA_8;
				break;
		}
		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
			dev_err(&port->dev, "Number of data bits requested "
					"not supported by device\n");
	}

	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
		cp2101_get_config(port, CP2101_BITS, &bits, 2);
		bits &= ~BITS_PARITY_MASK;
		if (cflag & PARENB) {
			if (cflag & PARODD) {
				bits |= BITS_PARITY_ODD;
				dbg("%s - parity = ODD", __FUNCTION__);
			} else {
				bits |= BITS_PARITY_EVEN;
				dbg("%s - parity = EVEN", __FUNCTION__);
			}
		}
		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
			dev_err(&port->dev, "Parity mode not supported "
					"by device\n");
	}

	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
		cp2101_get_config(port, CP2101_BITS, &bits, 2);
		bits &= ~BITS_STOP_MASK;
		if (cflag & CSTOPB) {
			bits |= BITS_STOP_2;
			dbg("%s - stop bits = 2", __FUNCTION__);
		} else {
			bits |= BITS_STOP_1;
			dbg("%s - stop bits = 1", __FUNCTION__);
		}
		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
			dev_err(&port->dev, "Number of stop bits requested "
					"not supported by device\n");
	}

	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
		cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
				__FUNCTION__, modem_ctl[0], modem_ctl[1],
				modem_ctl[2], modem_ctl[3]);

		if (cflag & CRTSCTS) {
			modem_ctl[0] &= ~0x7B;
			modem_ctl[0] |= 0x09;
			modem_ctl[1] = 0x80;
			dbg("%s - flow control = CRTSCTS", __FUNCTION__);
		} else {
			modem_ctl[0] &= ~0x7B;
			modem_ctl[0] |= 0x01;
			modem_ctl[1] |= 0x40;
			dbg("%s - flow control = NONE", __FUNCTION__);
		}

		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
				__FUNCTION__, modem_ctl[0], modem_ctl[1],
				modem_ctl[2], modem_ctl[3]);
		cp2101_set_config(port, CP2101_MODEMCTL, modem_ctl, 16);
	}

}

static int cp2101_tiocmset (struct usb_serial_port *port, struct file *file,
		unsigned int set, unsigned int clear)
{
	int control = 0;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (set & TIOCM_RTS) {
		control |= CONTROL_RTS;
		control |= CONTROL_WRITE_RTS;
	}
	if (set & TIOCM_DTR) {
		control |= CONTROL_DTR;
		control |= CONTROL_WRITE_DTR;
	}
	if (clear & TIOCM_RTS) {
		control &= ~CONTROL_RTS;
		control |= CONTROL_WRITE_RTS;
	}
	if (clear & TIOCM_DTR) {
		control &= ~CONTROL_DTR;
		control |= CONTROL_WRITE_DTR;
	}

	dbg("%s - control = 0x%.4x", __FUNCTION__, control);

	return cp2101_set_config(port, CP2101_CONTROL, &control, 2);

}

static int cp2101_tiocmget (struct usb_serial_port *port, struct file *file)
{
	int control, result;

	dbg("%s - port %d", __FUNCTION__, port->number);

	cp2101_get_config(port, CP2101_CONTROL, &control, 1);

	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
		|((control & CONTROL_RING)? TIOCM_RI  : 0)
		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);

	dbg("%s - control = 0x%.2x", __FUNCTION__, control);

	return result;
}

static void cp2101_break_ctl (struct usb_serial_port *port, int break_state)
{
	int state;

	dbg("%s - port %d", __FUNCTION__, port->number);
	if (break_state == 0)
		state = BREAK_OFF;
	else
		state = BREAK_ON;
	dbg("%s - turning break %s", __FUNCTION__,
			state==BREAK_OFF ? "off" : "on");
	cp2101_set_config(port, CP2101_BREAK, &state, 2);
}

static int cp2101_startup (struct usb_serial *serial)
{
	/* CP2101 buffers behave strangely unless device is reset */
	usb_reset_device(serial->dev);
	return 0;
}

static void cp2101_shutdown (struct usb_serial *serial)
{
	int i;

	dbg("%s", __FUNCTION__);

	/* Stop reads and writes on all ports */
	for (i=0; i < serial->num_ports; ++i) {
		cp2101_cleanup(serial->port[i]);
	}
}

static int __init cp2101_init (void)
{
	int retval;

	retval = usb_serial_register(&cp2101_device);
	if (retval)
		return retval; /* Failed to register */

	retval = usb_register(&cp2101_driver);
	if (retval) {
		/* Failed to register */
		usb_serial_deregister(&cp2101_device);
		return retval;
	}

	/* Success */
	info(DRIVER_DESC " " DRIVER_VERSION);
	return 0;
}

static void __exit cp2101_exit (void)
{
	usb_deregister (&cp2101_driver);
	usb_serial_deregister (&cp2101_device);
}

module_init(cp2101_init);
module_exit(cp2101_exit);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Enable verbose debugging messages");