USB: ftdi_sio: refactor modem-control status retrieval

[deliverable/linux.git] / drivers / usb / serial / ftdi_sio.c

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index be845873e23dba98fc306fecceb71a672a2c7d74..06b5d75dffc62e72f71aee0185715dc0c5f8f21d 100644 (file)
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -73,7 +73,6 @@ struct ftdi_private {
        char prev_status;        /* Used for TIOCMIWAIT */
        bool dev_gone;        /* Used to abort TIOCMIWAIT */
        char transmit_empty;    /* If transmitter is empty or not */
-       struct usb_serial_port *port;
        __u16 interface;        /* FT2232C, FT2232H or FT4232H port interface
                                   (0 for FT232/245) */
 
@@ -923,6 +922,7 @@ static int ftdi_get_icount(struct tty_struct *tty,
 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 unsigned short int ftdi_232am_baud_base_to_divisor(int baud, int base);
 static unsigned short int ftdi_232am_baud_to_divisor(int baud);
@@ -957,6 +957,7 @@ static struct usb_serial_driver ftdi_sio_device = {
        .ioctl =                ftdi_ioctl,
        .set_termios =          ftdi_set_termios,
        .break_ctl =            ftdi_break_ctl,
+       .chars_in_buffer =      ftdi_chars_in_buffer,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {
@@ -1090,6 +1091,7 @@ static int update_mctrl(struct usb_serial_port *port, unsigned int set,
                        __func__,
                        (set & TIOCM_DTR) ? "HIGH" : (clear & TIOCM_DTR) ? "LOW" : "unchanged",
                        (set & TIOCM_RTS) ? "HIGH" : (clear & TIOCM_RTS) ? "LOW" : "unchanged");
+               rv = usb_translate_errors(rv);
        } else {
                dev_dbg(dev, "%s - DTR %s, RTS %s\n", __func__,
                        (set & TIOCM_DTR) ? "HIGH" : (clear & TIOCM_DTR) ? "LOW" : "unchanged",
@@ -1682,7 +1684,6 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
 
        kref_init(&priv->kref);
        mutex_init(&priv->cfg_lock);
-       memset(&priv->icount, 0x00, sizeof(priv->icount));
        init_waitqueue_head(&priv->delta_msr_wait);
 
        priv->flags = ASYNC_LOW_LATENCY;
@@ -1691,7 +1692,6 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
        if (quirk && quirk->port_probe)
                quirk->port_probe(priv);
 
-       priv->port = port;
        usb_set_serial_port_data(port, priv);
 
        ftdi_determine_type(port);
@@ -2089,6 +2089,64 @@ 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);
+       unsigned long flags;
+       int chars;
+       unsigned char *buf;
+       int ret;
+
+       /* Check software buffer (code from
+        * usb_serial_generic_chars_in_buffer()) */
+       spin_lock_irqsave(&port->lock, flags);
+       chars = kfifo_len(&port->write_fifo) + port->tx_bytes;
+       spin_unlock_irqrestore(&port->lock, flags);
+
+       /* 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;
+       }
+
+       if (!(buf[1] & FTDI_RS_TEMT))
+               chars++;
+
+chars_in_buffer_out:
+       kfree(buf);
+       return chars;
+}
+
 /* old_termios contains the original termios settings and tty->termios contains
  * the new setting to be used
  * WARNING: set_termios calls this with old_termios in kernel space
@@ -2272,7 +2330,14 @@ no_c_cflag_changes:
        }
 }
 
-static int ftdi_tiocmget(struct tty_struct *tty)
+/*
+ * Get modem-control status.
+ *
+ * Returns the number of status bytes retrieved (device dependant), or
+ * negative error code.
+ */
+static int ftdi_get_modem_status(struct tty_struct *tty,
+                                               unsigned char status[2])
 {
        struct usb_serial_port *port = tty->driver_data;
        struct ftdi_private *priv = usb_get_serial_port_data(port);
@@ -2312,16 +2377,43 @@ static int ftdi_tiocmget(struct tty_struct *tty)
                        FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
                        0, priv->interface,
                        buf, len, WDR_TIMEOUT);
-       if (ret < 0)
+       if (ret < 0) {
+               dev_err(&port->dev, "failed to get modem status: %d\n", ret);
+               ret = usb_translate_errors(ret);
                goto out;
+       }
 
-       ret = (buf[0] & FTDI_SIO_DSR_MASK ? TIOCM_DSR : 0) |
-               (buf[0] & FTDI_SIO_CTS_MASK ? TIOCM_CTS : 0) |
-               (buf[0]  & FTDI_SIO_RI_MASK  ? TIOCM_RI  : 0) |
-               (buf[0]  & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0) |
-               priv->last_dtr_rts;
+       status[0] = buf[0];
+       if (ret > 1)
+               status[1] = buf[1];
+       else
+               status[1] = 0;
+
+       dev_dbg(&port->dev, "%s - 0x%02x%02x\n", __func__, status[0],
+                                                               status[1]);
 out:
        kfree(buf);
+
+       return ret;
+}
+
+static int ftdi_tiocmget(struct tty_struct *tty)
+{
+       struct usb_serial_port *port = tty->driver_data;
+       struct ftdi_private *priv = usb_get_serial_port_data(port);
+       unsigned char buf[2];
+       int ret;
+
+       ret = ftdi_get_modem_status(tty, buf);
+       if (ret < 0)
+               return ret;
+
+       ret =   (buf[0] & FTDI_SIO_DSR_MASK  ? TIOCM_DSR : 0) |
+               (buf[0] & FTDI_SIO_CTS_MASK  ? TIOCM_CTS : 0) |
+               (buf[0] & FTDI_SIO_RI_MASK   ? TIOCM_RI  : 0) |
+               (buf[0] & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0) |
+               priv->last_dtr_rts;
+
        return ret;
 }