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: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index b8bc9d0..8c3379b 100644 (file)
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -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;
-       }
+               goto out;
 
-       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;
+       /* Check if hardware buffer is empty. */
+       ret = ftdi_get_modem_status(tty, buf);
+       if (ret == 2) {
+               if (!(buf[1] & FTDI_RS_TEMT))
+                       chars = 1;
        }
+out:
+       dev_dbg(&port->dev, "%s - %d\n", __func__, chars);
 
-       if (!(buf[1] & FTDI_RS_TEMT))
-               chars++;
-
-chars_in_buffer_out:
-       kfree(buf);
        return chars;
 }