Commit 5fb0432e authored by Johan Hovold's avatar Johan Hovold Committed by Greg Kroah-Hartman
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USB: ftdi_sio: use ftdi_get_modem_status in chars_in_buffer 



Use ftdi_get_modem_status to check hardware buffers in chars_in_buffer.

Signed-off-by: default avatarJohan Hovold <jhovold@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8da636d9

drivers/usb/serial/ftdi_sio.c

+11 −41
Original line number Diff line number Diff line
@@ -923,6 +923,8 @@ static int ftdi_ioctl(struct tty_struct *tty, 
			unsigned int cmd, unsigned long arg);

static void ftdi_break_ctl(struct tty_struct *tty, int break_state);

static int ftdi_chars_in_buffer(struct tty_struct *tty);

static int ftdi_get_modem_status(struct tty_struct *tty,

						unsigned char status[2]);



static unsigned short int ftdi_232am_baud_base_to_divisor(int baud, int base);

static unsigned short int ftdi_232am_baud_to_divisor(int baud);
@@ -2092,55 +2094,23 @@ static void ftdi_break_ctl(struct tty_struct *tty, int break_state) 
static int ftdi_chars_in_buffer(struct tty_struct *tty)

{

	struct usb_serial_port *port = tty->driver_data;

	struct ftdi_private *priv = usb_get_serial_port_data(port);

	int chars;

	unsigned char *buf;

	unsigned char buf[2];

	int ret;



	chars = usb_serial_generic_chars_in_buffer(tty);

	if (chars)

		return chars;



	/* Check hardware buffer */

	switch (priv->chip_type) {

	case FT8U232AM:

	case FT232BM:

	case FT2232C:

	case FT232RL:

	case FT2232H:

	case FT4232H:

	case FT232H:

	case FTX:

		break;

	case SIO:

	default:

		return chars;

	}



	buf = kmalloc(2, GFP_KERNEL);

	if (!buf) {

		dev_err(&port->dev, "kmalloc failed");

		return chars;

	}



	ret = usb_control_msg(port->serial->dev,

				usb_rcvctrlpipe(port->serial->dev, 0),

				FTDI_SIO_GET_MODEM_STATUS_REQUEST,

				FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,

				0, priv->interface,

				buf, 2, WDR_TIMEOUT);



	if (ret < 2) {

		dev_err(&port->dev, "Unable to read modem and line status: "

			"%i\n", ret);

		goto chars_in_buffer_out;

	}

		goto out;



	/* Check if hardware buffer is empty. */

	ret = ftdi_get_modem_status(tty, buf);

	if (ret == 2) {

		if (!(buf[1] & FTDI_RS_TEMT))

		chars++;

			chars = 1;

	}

out:

	dev_dbg(&port->dev, "%s - %d\n", __func__, chars);



chars_in_buffer_out:

	kfree(buf);

	return chars;

}