Commit d4297629 authored by Johan Hovold's avatar Johan Hovold
Browse files

USB: serial: cp210x: clean up line-control handling 



Update the line-control settings in one request unconditionally instead
of setting the word-length, parity and stop-bit settings separately.

This avoids multiple requests when several settings are changed even if
this scheme could potentially also be used to detect unsupported device
settings. Since all device types but CP2101 appears to support all
settings, let's handle that one specifically and also report back the
unsupported settings properly through termios by clearing the
corresponding bits.

Also drop the related unnecessary debug printks.

Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
parent 95168d62

drivers/usb/serial/cp210x.c

+41 −60
Original line number Diff line number Diff line
@@ -1364,9 +1364,11 @@ static bool cp210x_termios_change(const struct ktermios *a, const struct ktermio 
static void cp210x_set_termios(struct tty_struct *tty,

		struct usb_serial_port *port, struct ktermios *old_termios)

{

	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);

	struct device *dev = &port->dev;

	unsigned int cflag, old_cflag;

	u16 bits;

	int ret;



	if (!cp210x_termios_change(&tty->termios, old_termios))

		return;
@@ -1377,73 +1379,52 @@ static void cp210x_set_termios(struct tty_struct *tty, 
	if (tty->termios.c_ospeed != old_termios->c_ospeed)

		cp210x_change_speed(tty, port, old_termios);



	/* If the number of data bits is to be updated */

	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {

		cp210x_get_line_ctl(port, &bits);

		bits &= ~BITS_DATA_MASK;

		switch (cflag & CSIZE) {

	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */

	if (priv->partnum == CP210X_PARTNUM_CP2101) {

		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);

		tty->termios.c_cflag |= CS8;

	}



	bits = 0;



	switch (C_CSIZE(tty)) {

	case CS5:

		bits |= BITS_DATA_5;

			dev_dbg(dev, "%s - data bits = 5\n", __func__);

		break;

	case CS6:

		bits |= BITS_DATA_6;

			dev_dbg(dev, "%s - data bits = 6\n", __func__);

		break;

	case CS7:

		bits |= BITS_DATA_7;

			dev_dbg(dev, "%s - data bits = 7\n", __func__);

		break;

	case CS8:

	default:

		bits |= BITS_DATA_8;

			dev_dbg(dev, "%s - data bits = 8\n", __func__);

		break;

	}

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Number of data bits requested not supported by device\n");

	}



	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=

	    (old_cflag & (PARENB|PARODD|CMSPAR))) {

		cp210x_get_line_ctl(port, &bits);

		bits &= ~BITS_PARITY_MASK;

		if (cflag & PARENB) {

			if (cflag & CMSPAR) {

				if (cflag & PARODD) {

	if (C_PARENB(tty)) {

		if (C_CMSPAR(tty)) {

			if (C_PARODD(tty))

				bits |= BITS_PARITY_MARK;

					dev_dbg(dev, "%s - parity = MARK\n", __func__);

				} else {

			else

				bits |= BITS_PARITY_SPACE;

					dev_dbg(dev, "%s - parity = SPACE\n", __func__);

				}

		} else {

				if (cflag & PARODD) {

			if (C_PARODD(tty))

				bits |= BITS_PARITY_ODD;

					dev_dbg(dev, "%s - parity = ODD\n", __func__);

				} else {

			else

				bits |= BITS_PARITY_EVEN;

					dev_dbg(dev, "%s - parity = EVEN\n", __func__);

				}

		}

	}

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Parity mode not supported by device\n");

	}



	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {

		cp210x_get_line_ctl(port, &bits);

		bits &= ~BITS_STOP_MASK;

		if (cflag & CSTOPB) {

	if (C_CSTOPB(tty))

		bits |= BITS_STOP_2;

			dev_dbg(dev, "%s - stop bits = 2\n", __func__);

		} else {

	else

		bits |= BITS_STOP_1;

			dev_dbg(dev, "%s - stop bits = 1\n", __func__);

		}

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Number of stop bits requested not supported by device\n");

	}



	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

	if (ret)

		dev_err(&port->dev, "failed to set line control: %d\n", ret);



	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {

		struct cp210x_flow_ctl flow_ctl;

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