serqt: initial clean up pass for tty side

Avoid using port->tty where possible (makes refcount fixing easier
later).

Remove unused code (the ioctl path is not used if the device has
mget/mset functions)

Remove various un-needed typecasts and long names so it could read it to
do the changes.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 163 insertions, 286 deletions

diff --git a/drivers/staging/serqt_usb/serqt_usb.c b/drivers/staging/serqt_usb/serqt_usb.c
index 1781510c53fd..234f332fc82f 100644
--- a/drivers/staging/serqt_usb/serqt_usb.c
+++ b/drivers/staging/serqt_usb/serqt_usb.c
@@ -289,7 +289,8 @@ static void serial_unthrottle(struct tty_struct *tty);
 static int serial_break(struct tty_struct *tty, int break_state);
 static int serial_chars_in_buffer(struct tty_struct *tty);
 
-static int qt_open(struct usb_serial_port *port, struct file *filp);
+static int qt_open(struct tty_struct *tty, struct usb_serial_port *port,
+                                struct file *filp);
 static int BoxSetPrebufferLevel(struct usb_serial *serial);
 
 static int BoxSetATC(struct usb_serial *serial, __u16 n_Mode);
@@ -300,24 +301,26 @@ static int BoxSetUart(struct usb_serial *serial, unsigned short Uart_Number,
 static int BoxOPenCloseChannel(struct usb_serial *serial, __u16 Uart_Number,
                                __u16 OpenClose,
                                struct qt_open_channel_data *pDeviceData);
-static void qt_close(struct usb_serial_port *port, struct file *filp);
+static void qt_close(struct tty_struct *tty, struct usb_serial_port *port,
+                                        struct file *filp);
 static int BoxGetRegister(struct usb_serial *serial, unsigned short Uart_Number,
                           unsigned short Register_Num, __u8 *pValue);
 static int BoxSetRegister(struct usb_serial *serial, unsigned short Uart_Number,
                           unsigned short Register_Num, unsigned short Value);
 static void qt_write_bulk_callback(struct urb *urb);
-static int qt_write(struct usb_serial_port *port, int from_user,
+static int qt_write(struct tty_struct *tty, struct usb_serial_port *port,
                     const unsigned char *buf, int count);
 static void port_softint(struct work_struct *work);
 static int qt_write_room(struct usb_serial_port *port);
 static int qt_chars_in_buffer(struct usb_serial_port *port);
-static int qt_ioctl(struct usb_serial_port *port, struct file *file,
-                    unsigned int cmd, unsigned long arg);
-static void qt_set_termios(struct usb_serial_port *port,
+static int qt_ioctl(struct tty_struct *tty, struct usb_serial_port *port,
+                struct file *file, unsigned int cmd, unsigned long arg);
+static void qt_set_termios(struct tty_struct *tty,
+                           struct usb_serial_port *port,
                            struct ktermios *old_termios);
-static int BoxSetHW_FlowCtrl(struct usb_serial *serial, unsigned int UartNumber,
+static int BoxSetHW_FlowCtrl(struct usb_serial *serial, unsigned int index,
                              int bSet);
-static int BoxDisable_SW_FlowCtrl(struct usb_serial *serial, __u16 UartNumber);
+static int BoxDisable_SW_FlowCtrl(struct usb_serial *serial, __u16 index);
 static int EmulateWriteQMCR_Reg(int index, unsigned uc_value);
 static int EmulateReadQMCR_Reg(int index, unsigned *uc_value);
 static struct usb_serial *find_the_box(unsigned int index);
@@ -336,10 +339,11 @@ static int serial_tiocmset(struct tty_struct *tty, struct file *file,
                            unsigned int set, unsigned int clear);
 static int serial_tiocmget(struct tty_struct *tty, struct file *file);
 
-static int qt_tiocmset(struct usb_serial_port *port, struct file *file,
-                       unsigned int value);
+static int qt_tiocmset(struct tty_struct *tty, struct usb_serial_port *port,
+                       struct file *file, unsigned int value);
 
-static int qt_tiocmget(struct usb_serial_port *port, struct file *file);
+static int qt_tiocmget(struct tty_struct *tty, struct usb_serial_port *port,
+                                                        struct file *file);
 
 /* Version Information */
 #define DRIVER_VERSION "v2.14"
@@ -818,7 +822,7 @@ static struct usb_serial *get_free_serial(int num_ports, int *minor)
         return NULL;
 }
 
-static int flip_that(struct tty_struct *tty, __u16 UartNumber,
+static int flip_that(struct tty_struct *tty, __u16 index,
                      struct usb_serial *serial)
 {
         tty_flip_buffer_push(tty);
@@ -829,18 +833,18 @@ static int flip_that(struct tty_struct *tty, __u16 UartNumber,
 /* Handles processing and moving data to the tty layer */
 static void port_sofrint(void *private)
 {
-        struct usb_serial_port *port = (struct usb_serial_port *)private;
+        struct usb_serial_port *port = private;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         struct tty_struct *tty = port->tty;
         unsigned char *data = port->read_urb->transfer_buffer;
-        unsigned int UartNumber;
+        unsigned int index;
         struct urb *urb = port->read_urb;
         unsigned int RxCount = urb->actual_length;
         int i, result;
         int flag, flag_data;
 
-        /* UartNumber = MINOR(port->tty->device) - serial->minor; */
-        UartNumber = tty->index - serial->minor;
+        /* index = MINOR(port->tty->device) - serial->minor; */
+        index = tty->index - serial->minor;
 
         mydbg("%s - port %d\n", __func__, port->number);
         mydbg("%s - port->RxHolding = %d\n", __func__, port->RxHolding);
@@ -948,7 +952,7 @@ static void port_sofrint(void *private)
                       __func__, result);
         else {
                 if (tty && RxCount)
-                        flip_that(tty, UartNumber, serial);
+                        flip_that(tty, index, serial);
         }
 
         return;
@@ -1097,7 +1101,7 @@ static int serial_open(struct tty_struct *tty, struct file *filp)
                 port->RxHolding = 0;
                 mydbg("%s port->RxHolding = 0\n", __func__);
 
-                retval = qt_open(port, filp);
+                retval = qt_open(tty, port, filp);
         }
 
         if (retval)
@@ -1112,11 +1116,12 @@ static int serial_open(struct tty_struct *tty, struct file *filp)
 /*****************************************************************************
  *device's specific driver functions
  *****************************************************************************/
-static int qt_open(struct usb_serial_port *port, struct file *filp)
+static int qt_open(struct tty_struct *tty, struct usb_serial_port *port,
+                                        struct file *filp)
 {
         struct usb_serial *serial = port->serial;
         int result = 0;
-        unsigned int UartNumber;
+        unsigned int index;
         struct qt_get_device_data DeviceData;
         struct qt_open_channel_data ChannelData;
         unsigned short default_divisor = 0x30;          /* gives 9600 baud rate */
@@ -1128,13 +1133,7 @@ static int qt_open(struct usb_serial_port *port, struct file *filp)
 
         mydbg("%s - port %d\n", __func__, port->number);
 
-        /* force low_latency on so that our tty_push actually forces the data through,
-           otherwise it is scheduled, and with high data rates (like with OHCI) data
-           can get lost. */
-        if (port->tty)
-                port->tty->low_latency = 0;
-
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         status = box_get_device(serial, &DeviceData);
         if (status < 0) {
@@ -1147,7 +1146,7 @@ static int qt_open(struct usb_serial_port *port, struct file *filp)
         /* Open uart channel */
 
         /* Port specific setups */
-        status = BoxOPenCloseChannel(serial, UartNumber, 1, &ChannelData);
+        status = BoxOPenCloseChannel(serial, index, 1, &ChannelData);
         if (status < 0) {
                 mydbg(__FILE__ "BoxOPenCloseChannel failed\n");
                 return status;
@@ -1161,7 +1160,7 @@ static int qt_open(struct usb_serial_port *port, struct file *filp)
             (SERIAL_MSR_CTS | SERIAL_MSR_DSR | SERIAL_MSR_RI | SERIAL_MSR_CD);
 
         /* Set Baud rate to default and turn off (default)flow control here */
-        status = BoxSetUart(serial, UartNumber, default_divisor, default_LCR);
+        status = BoxSetUart(serial, index, default_divisor, default_LCR);
         if (status < 0) {
                 mydbg(__FILE__ "BoxSetUart failed\n");
                 return status;
@@ -1169,7 +1168,7 @@ static int qt_open(struct usb_serial_port *port, struct file *filp)
         mydbg(__FILE__ "BoxSetUart completed.\n");
 
         /* Put this here to make it responsive to stty and defauls set by the tty layer */
-        qt_set_termios(port, NULL);
+        qt_set_termios(tty, port, NULL);
 
         /* Initialize the wait que head */
         init_waitqueue_head(&(port->wait));
@@ -1203,7 +1202,7 @@ static int qt_open(struct usb_serial_port *port, struct file *filp)
 static void serial_close(struct tty_struct *tty, struct file *filp)
 {
         struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+            tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
 
         if (!serial)
@@ -1226,7 +1225,7 @@ static void serial_close(struct tty_struct *tty, struct file *filp)
                         mydbg("%s - port->closePending = 1\n", __func__);
 
                         if (serial->dev) {
-                                qt_close(port, filp);
+                                qt_close(tty, port, filp);
                                 port->open_count = 0;
                         }
                 }
@@ -1240,20 +1239,21 @@ exit:
 
 }
 
-static void qt_close(struct usb_serial_port *port, struct file *filp)
+static void qt_close(struct tty_struct *tty, struct usb_serial_port *port,
+                                                        struct file *filp)
 {
         unsigned long jift = jiffies + 10 * HZ;
-        __u8 LSR_Value, MCR_Value;
+        u8 lsr, mcr;
         struct usb_serial *serial = port->serial;
         int status;
-        unsigned int UartNumber;
+        unsigned int index;
 
         struct qt_open_channel_data ChannelData;
         status = 0;
-        LSR_Value = 0;
+        lsr = 0;
 
         mydbg("%s - port %d\n", __func__, port->number);
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         /* shutdown any bulk reads that might be going on */
         if (serial->num_bulk_out)
@@ -1263,20 +1263,19 @@ static void qt_close(struct usb_serial_port *port, struct file *filp)
 
         /* wait up to 30 seconds for transmitter to empty */
         do {
-                status = BoxGetRegister(serial, UartNumber, LINE_STATUS_REGISTER, &LSR_Value);
+                status = BoxGetRegister(serial, index, LINE_STATUS_REGISTER, &lsr);
                 if (status < 0) {
                         mydbg(__FILE__ "box_get_device failed\n");
                         break;
                 }
 
-                if ((LSR_Value & SERIAL_LSR_TEMT)
+                if ((lsr & SERIAL_LSR_TEMT)
                     && (port->ReadBulkStopped == 1))
                         break;
                 schedule();
 
         }
-        while (jiffies <= jift)
-                ;
+        while (jiffies <= jift);
 
         if (jiffies > jift)
                 mydbg("%s - port %d timout of checking transmitter empty\n",
@@ -1286,17 +1285,17 @@ static void qt_close(struct usb_serial_port *port, struct file *filp)
                       __func__, port->number);
 
         status =
-            BoxGetRegister(serial, UartNumber, MODEM_CONTROL_REGISTER,
-                           &MCR_Value);
-        mydbg(__FILE__ "BoxGetRegister MCR = 0x%x.\n", MCR_Value);
+            BoxGetRegister(serial, index, MODEM_CONTROL_REGISTER,
+                           &mcr);
+        mydbg(__FILE__ "BoxGetRegister MCR = 0x%x.\n", mcr);
 
         if (status >= 0) {
-                MCR_Value &= ~(SERIAL_MCR_DTR | SERIAL_MCR_RTS);
-                /* status = BoxSetRegister(serial, UartNumber, MODEM_CONTROL_REGISTER, MCR_Value); */
+                mcr &= ~(SERIAL_MCR_DTR | SERIAL_MCR_RTS);
+                /* status = BoxSetRegister(serial, index, MODEM_CONTROL_REGISTER, mcr); */
         }
 
         /* Close uart channel */
-        status = BoxOPenCloseChannel(serial, UartNumber, 0, &ChannelData);
+        status = BoxOPenCloseChannel(serial, index, 0, &ChannelData);
         if (status < 0)
                 mydbg("%s - port %d BoxOPenCloseChannel failed.\n",
                       __func__, port->number);
@@ -1308,12 +1307,10 @@ static void qt_close(struct usb_serial_port *port, struct file *filp)
 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
                         int count)
 {
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial;
         int retval = -EINVAL;
-        unsigned int UartNumber;
-        int from_user = 0;
+        unsigned int index;
 
         serial = get_usb_serial(port, __func__);
         if (serial == NULL)
@@ -1321,7 +1318,7 @@ static int serial_write(struct tty_struct *tty, const unsigned char *buf,
         /* This can happen if we get disconnected a */
         if (port->open_count == 0)
                 return -ENODEV;
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         mydbg("%s - port %d, %d byte(s)\n", __func__, port->number, count);
         mydbg("%s - port->RxHolding =  %d\n", __func__, port->RxHolding);
@@ -1331,19 +1328,19 @@ static int serial_write(struct tty_struct *tty, const unsigned char *buf,
                 goto exit;
         }
 
-        retval = qt_write(port, from_user, buf, count);
+        retval = qt_write(tty, port, buf, count);
 
 exit:
         return retval;
 }
 
-static int qt_write(struct usb_serial_port *port, int from_user,
-                    const unsigned char *buf, int count)
+static int qt_write(struct tty_struct *tty, struct usb_serial_port *port,
+                                const unsigned char *buf, int count)
 {
         int result;
-        unsigned int UartNumber;
-
+        unsigned int index;
         struct usb_serial *serial = get_usb_serial(port, __func__);
+
         if (serial == NULL)
                 return -ENODEV;
 
@@ -1354,7 +1351,7 @@ static int qt_write(struct usb_serial_port *port, int from_user,
                 return 0;
         }
 
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
         /* only do something if we have a bulk out endpoint */
         if (serial->num_bulk_out) {
                 if (port->write_urb->status == -EINPROGRESS) {
@@ -1364,14 +1361,7 @@ static int qt_write(struct usb_serial_port *port, int from_user,
 
                 count =
                     (count > port->bulk_out_size) ? port->bulk_out_size : count;
-
-                if (from_user) {
-                        if (copy_from_user
-                            (port->write_urb->transfer_buffer, buf, count))
-                                return -EFAULT;
-                } else {
-                        memcpy(port->write_urb->transfer_buffer, buf, count);
-                }
+                memcpy(port->write_urb->transfer_buffer, buf, count);
 
                 /* usb_serial_debug_data(__FILE__, __func__, count, port->write_urb->transfer_buffer); */
 
@@ -1449,8 +1439,7 @@ static void port_softint(struct work_struct *work)
 }
 static int serial_write_room(struct tty_struct *tty)
 {
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         int retval = -EINVAL;
 
@@ -1493,8 +1482,7 @@ static int qt_write_room(struct usb_serial_port *port)
 }
 static int serial_chars_in_buffer(struct tty_struct *tty)
 {
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         int retval = -EINVAL;
 
@@ -1537,17 +1525,16 @@ static int serial_tiocmset(struct tty_struct *tty, struct file *file,
                            unsigned int set, unsigned int clear)
 {
 
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         int retval = -ENODEV;
-        unsigned int UartNumber;
+        unsigned int index;
         mydbg("In %s \n", __func__);
 
         if (!serial)
                 return -ENODEV;
 
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         down(&port->sem);
 
@@ -1559,22 +1546,22 @@ static int serial_tiocmset(struct tty_struct *tty, struct file *file,
                 goto exit;
         }
 
-        retval = qt_tiocmset(port, file, set);
+        retval = qt_tiocmset(tty, port, file, set);
 
 exit:
         up(&port->sem);
         return retval;
 }
 
-static int qt_tiocmset(struct usb_serial_port *port, struct file *file,
-                       unsigned int value)
+static int qt_tiocmset(struct tty_struct *tty, struct usb_serial_port *port,
+                       struct file *file, unsigned int value)
 {
 
-        __u8 MCR_Value;
+        u8 mcr;
         int status;
-        unsigned int UartNumber;
-
+        unsigned int index;
         struct usb_serial *serial = get_usb_serial(port, __func__);
+
         if (serial == NULL)
                 return -ENODEV;
 
@@ -1583,10 +1570,10 @@ static int qt_tiocmset(struct usb_serial_port *port, struct file *file,
     /**************************************************************************************/
     /**  TIOCMGET
      */
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
         status =
-            BoxGetRegister(port->serial, UartNumber, MODEM_CONTROL_REGISTER,
-                           &MCR_Value);
+            BoxGetRegister(port->serial, index, MODEM_CONTROL_REGISTER,
+                           &mcr);
         if (status < 0)
                 return -ESPIPE;
 
@@ -1594,17 +1581,17 @@ static int qt_tiocmset(struct usb_serial_port *port, struct file *file,
          * Turn off the RTS and DTR and loopbcck and then only turn on what was
          * asked for
          */
-        MCR_Value &= ~(SERIAL_MCR_RTS | SERIAL_MCR_DTR | SERIAL_MCR_LOOP);
+        mcr &= ~(SERIAL_MCR_RTS | SERIAL_MCR_DTR | SERIAL_MCR_LOOP);
         if (value & TIOCM_RTS)
-                MCR_Value |= SERIAL_MCR_RTS;
+                mcr |= SERIAL_MCR_RTS;
         if (value & TIOCM_DTR)
-                MCR_Value |= SERIAL_MCR_DTR;
+                mcr |= SERIAL_MCR_DTR;
         if (value & TIOCM_LOOP)
-                MCR_Value |= SERIAL_MCR_LOOP;
+                mcr |= SERIAL_MCR_LOOP;
 
         status =
-            BoxSetRegister(port->serial, UartNumber, MODEM_CONTROL_REGISTER,
-                           MCR_Value);
+            BoxSetRegister(port->serial, index, MODEM_CONTROL_REGISTER,
+                           mcr);
         if (status < 0)
                 return -ESPIPE;
         else
@@ -1614,18 +1601,16 @@ static int qt_tiocmset(struct usb_serial_port *port, struct file *file,
 static int serial_tiocmget(struct tty_struct *tty, struct file *file)
 {
 
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
-
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         int retval = -ENODEV;
-        unsigned int UartNumber;
+        unsigned int index;
         mydbg("In %s \n", __func__);
 
         if (!serial)
                 return -ENODEV;
 
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         down(&port->sem);
 
@@ -1637,56 +1622,55 @@ static int serial_tiocmget(struct tty_struct *tty, struct file *file)
                 goto exit;
         }
 
-        retval = qt_tiocmget(port, file);
+        retval = qt_tiocmget(tty, port, file);
 
 exit:
         up(&port->sem);
         return retval;
 }
 
-static int qt_tiocmget(struct usb_serial_port *port, struct file *file)
+static int qt_tiocmget(struct tty_struct *tty,
+                        struct usb_serial_port *port, struct file *file)
 {
 
-        __u8 MCR_Value;
-        __u8 MSR_Value;
+        u8 mcr;
+        u8 msr;
         unsigned int result = 0;
         int status;
-        unsigned int UartNumber;
-        struct tty_struct *tty;
+        unsigned int index;
 
         struct usb_serial *serial = get_usb_serial(port, __func__);
         if (serial == NULL)
                 return -ENODEV;
-        tty = port->tty;
 
         mydbg("%s - port %d, tty =0x%p\n", __func__, port->number, tty);
 
     /**************************************************************************************/
     /**  TIOCMGET
      */
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
         status =
-            BoxGetRegister(port->serial, UartNumber, MODEM_CONTROL_REGISTER,
-                           &MCR_Value);
+            BoxGetRegister(port->serial, index, MODEM_CONTROL_REGISTER,
+                           &mcr);
         if (status >= 0) {
                 status =
-                    BoxGetRegister(port->serial, UartNumber,
-                                   MODEM_STATUS_REGISTER, &MSR_Value);
+                    BoxGetRegister(port->serial, index,
+                                   MODEM_STATUS_REGISTER, &msr);
 
         }
 
         if (status >= 0) {
-                result = ((MCR_Value & SERIAL_MCR_DTR) ? TIOCM_DTR : 0)
+                result = ((mcr & SERIAL_MCR_DTR) ? TIOCM_DTR : 0)
                     /* DTR IS SET */
-                    | ((MCR_Value & SERIAL_MCR_RTS) ? TIOCM_RTS : 0)
+                    | ((mcr & SERIAL_MCR_RTS) ? TIOCM_RTS : 0)
                     /* RTS IS SET */
-                    | ((MSR_Value & SERIAL_MSR_CTS) ? TIOCM_CTS : 0)
+                    | ((msr & SERIAL_MSR_CTS) ? TIOCM_CTS : 0)
                     /* CTS is set */
-                    | ((MSR_Value & SERIAL_MSR_CD) ? TIOCM_CAR : 0)
+                    | ((msr & SERIAL_MSR_CD) ? TIOCM_CAR : 0)
                     /* Carrier detect is set */
-                    | ((MSR_Value & SERIAL_MSR_RI) ? TIOCM_RI : 0)
+                    | ((msr & SERIAL_MSR_RI) ? TIOCM_RI : 0)
                     /* Ring indicator set */
-                    | ((MSR_Value & SERIAL_MSR_DSR) ? TIOCM_DSR : 0);
+                    | ((msr & SERIAL_MSR_DSR) ? TIOCM_DSR : 0);
                 /* DSR is set */
                 return result;
 
@@ -1698,17 +1682,16 @@ static int serial_ioctl(struct tty_struct *tty, struct file *file,
                         unsigned int cmd, unsigned long arg)
 {
 
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         int retval = -ENODEV;
-        unsigned int UartNumber;
+        unsigned int index;
         mydbg("In %s \n", __func__);
 
         if (!serial)
                 return -ENODEV;
 
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
 
         down(&port->sem);
 
@@ -1720,125 +1703,34 @@ static int serial_ioctl(struct tty_struct *tty, struct file *file,
                 goto exit;
         }
 
-        retval = qt_ioctl(port, file, cmd, arg);
+        retval = qt_ioctl(tty, port, file, cmd, arg);
 
 exit:
         up(&port->sem);
         return retval;
 }
-static int qt_ioctl(struct usb_serial_port *port, struct file *file,
-                    unsigned int cmd, unsigned long arg)
+static int qt_ioctl(struct tty_struct *tty, struct usb_serial_port *port,
+                        struct file *file, unsigned int cmd, unsigned long arg)
 {
-        __u8 MCR_Value;
-        __u8 MSR_Value;
-        unsigned short Prev_MSR_Value;
+        __u8 mcr;
+        __u8 msr;
+        unsigned short prev_msr;
         unsigned int value, result = 0;
         int status;
-        unsigned int UartNumber;
-        struct tty_struct *tty;
+        unsigned int index;
 
         struct usb_serial *serial = get_usb_serial(port, __func__);
         if (serial == NULL)
                 return -ENODEV;
-        tty = port->tty;
 
         mydbg("%s - port %d, tty =0x%p\n", __func__, port->number, tty);
 
         /* TIOCMGET */
-        UartNumber = port->tty->index - serial->minor;
-
-        if (cmd == TIOCMGET) {
-                MCR_Value = port->shadowMCR;
-                MSR_Value = port->shadowMSR;
-
-                {
-                        result = ((MCR_Value & SERIAL_MCR_DTR) ? TIOCM_DTR : 0)
-                            /* DTR IS SET */
-                            | ((MCR_Value & SERIAL_MCR_RTS) ? TIOCM_RTS : 0)
-                            /* RTS IS SET */
-                            | ((MSR_Value & SERIAL_MSR_CTS) ? TIOCM_CTS : 0)
-                            /* CTS is set */
-                            | ((MSR_Value & SERIAL_MSR_CD) ? TIOCM_CAR : 0)
-                            /* Carrier detect is set */
-                            | ((MSR_Value & SERIAL_MSR_RI) ? TIOCM_RI : 0)
-                            /* Ring indicator set */
-                            | ((MSR_Value & SERIAL_MSR_DSR) ? TIOCM_DSR : 0);
-                        /* DSR is set */
-                        if (copy_to_user
-                            ((unsigned int *)arg, &result,
-                             sizeof(unsigned int)))
-                                return -EFAULT;
-                        return 0;
-
-                }
-        }
-
-        /* TIOCMBIS, TIOCMBIC, AND TIOCMSET */
-        if (cmd == TIOCMBIS || cmd == TIOCMBIC || cmd == TIOCMSET) {
-                status =
-                    BoxGetRegister(port->serial, UartNumber,
-                                   MODEM_CONTROL_REGISTER, &MCR_Value);
-                if (status < 0)
-                        return -ESPIPE;
-                if (copy_from_user
-                    (&value, (unsigned int *)arg, sizeof(unsigned int)))
-                        return -EFAULT;
-
-                switch (cmd) {
-                case TIOCMBIS:
-                        if (value & TIOCM_RTS)
-                                MCR_Value |= SERIAL_MCR_RTS;
-                        if (value & TIOCM_DTR)
-                                MCR_Value |= SERIAL_MCR_DTR;
-                        if (value & TIOCM_LOOP)
-                                MCR_Value |= SERIAL_MCR_LOOP;
-                        break;
-                case TIOCMBIC:
-                        if (value & TIOCM_RTS)
-                                MCR_Value &= ~SERIAL_MCR_RTS;
-                        if (value & TIOCM_DTR)
-                                MCR_Value &= ~SERIAL_MCR_DTR;
-                        if (value & TIOCM_LOOP)
-                                MCR_Value &= ~SERIAL_MCR_LOOP;
-                        break;
-                case TIOCMSET:
-                        /*
-                         * Turn off the RTS and DTR and loopbcck and then only
-                         * turn on what was asked for
-                         */
-                        MCR_Value &=
-                            ~(SERIAL_MCR_RTS | SERIAL_MCR_DTR |
-                              SERIAL_MCR_LOOP);
-                        if (value & TIOCM_RTS)
-                                MCR_Value |= SERIAL_MCR_RTS;
-                        if (value & TIOCM_DTR)
-                                MCR_Value |= SERIAL_MCR_DTR;
-                        if (value & TIOCM_LOOP)
-                                MCR_Value |= SERIAL_MCR_LOOP;
-                        break;
-                default:
-                        break;
-
-                }
-                status =
-                    BoxSetRegister(port->serial, UartNumber,
-                                   MODEM_CONTROL_REGISTER, MCR_Value);
-                if (status < 0)
-                        return -ESPIPE;
-                else {
-                        port->shadowMCR = MCR_Value;
-                        return 0;
-                }
-
-        }
-    /**************************************************************************************/
-   /**   TIOCMBIS, TIOCMBIC, AND TIOCMSET    end
-   */
-    /**************************************************************************************/
+        index = tty->index - serial->minor;
 
         if (cmd == TIOCMIWAIT) {
                 DECLARE_WAITQUEUE(wait, current);
-                Prev_MSR_Value = port->shadowMSR & SERIAL_MSR_MASK;
+                prev_msr = port->shadowMSR & SERIAL_MSR_MASK;
                 while (1) {
                         add_wait_queue(&port->wait, &wait);
                         set_current_state(TASK_INTERRUPTIBLE);
@@ -1847,22 +1739,22 @@ static int qt_ioctl(struct usb_serial_port *port, struct file *file,
                         /* see if a signal woke us up */
                         if (signal_pending(current))
                                 return -ERESTARTSYS;
-                        MSR_Value = port->shadowMSR & SERIAL_MSR_MASK;
-                        if (MSR_Value == Prev_MSR_Value)
+                        msr = port->shadowMSR & SERIAL_MSR_MASK;
+                        if (msr == prev_msr)
                                 return -EIO;    /* no change error */
 
                         if ((arg & TIOCM_RNG
-                             && ((Prev_MSR_Value & SERIAL_MSR_RI) ==
-                                 (MSR_Value & SERIAL_MSR_RI)))
+                             && ((prev_msr & SERIAL_MSR_RI) ==
+                                 (msr & SERIAL_MSR_RI)))
                             || (arg & TIOCM_DSR
-                                && ((Prev_MSR_Value & SERIAL_MSR_DSR) ==
-                                    (MSR_Value & SERIAL_MSR_DSR)))
+                                && ((prev_msr & SERIAL_MSR_DSR) ==
+                                    (msr & SERIAL_MSR_DSR)))
                             || (arg & TIOCM_CD
-                                && ((Prev_MSR_Value & SERIAL_MSR_CD) ==
-                                    (MSR_Value & SERIAL_MSR_CD)))
+                                && ((prev_msr & SERIAL_MSR_CD) ==
+                                    (msr & SERIAL_MSR_CD)))
                             || (arg & TIOCM_CTS
-                                && ((Prev_MSR_Value & SERIAL_MSR_CTS) ==
-                                    (MSR_Value & SERIAL_MSR_CTS)))) {
+                                && ((prev_msr & SERIAL_MSR_CTS) ==
+                                    (msr & SERIAL_MSR_CTS)))) {
                                 return 0;
                         }
 
@@ -1878,7 +1770,7 @@ static int qt_ioctl(struct usb_serial_port *port, struct file *file,
 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
         struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+            tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
 
         if (!serial)
@@ -1894,22 +1786,22 @@ static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
         }
 
         /* pass on to the driver specific version of this function if it is available */
-        qt_set_termios(port, old);
+        qt_set_termios(tty, port, old);
 
 exit:
         up(&port->sem);
 }
 
-static void qt_set_termios(struct usb_serial_port *port,
+static void qt_set_termios(struct tty_struct *tty,
+                           struct usb_serial_port *port,
                            struct ktermios *old_termios)
 {
         unsigned int cflag;
         int baud, divisor, remainder;
-        unsigned char LCR_change_to = 0;
-        struct tty_struct *tty;
+        unsigned char new_LCR = 0;
         int status;
         struct usb_serial *serial;
-        __u16 UartNumber;
+        __u16 index;
         __u16 tmp, tmp2;
 
         mydbg("%s - port %d\n", __func__, port->number);
@@ -1921,59 +1813,46 @@ static void qt_set_termios(struct usb_serial_port *port,
         tmp2 = serial->minor;
         mydbg("%s - serial->minor =  %d\n", __func__, tmp2);
 
-        UartNumber = port->tty->index - serial->minor;
-
-        tty = port->tty;
+        index = port->tty->index - serial->minor;
 
         cflag = tty->termios->c_cflag;
 
-        if (old_termios) {
-                if ((cflag == old_termios->c_cflag)
-                    && (RELEVANT_IFLAG(tty->termios->c_iflag) ==
-                        RELEVANT_IFLAG(old_termios->c_iflag))) {
-                        mydbg("%s - Nothing to change\n", __func__);
-                        return;
-                }
-
-        }
-
         mydbg("%s - 3\n", __func__);
 
         switch (cflag) {
         case CS5:
-                LCR_change_to |= SERIAL_5_DATA;
+                new_LCR |= SERIAL_5_DATA;
                 break;
         case CS6:
-                LCR_change_to |= SERIAL_6_DATA;
+                new_LCR |= SERIAL_6_DATA;
                 break;
         case CS7:
-                LCR_change_to |= SERIAL_7_DATA;
+                new_LCR |= SERIAL_7_DATA;
                 break;
         default:
         case CS8:
-                LCR_change_to |= SERIAL_8_DATA;
+                new_LCR |= SERIAL_8_DATA;
                 break;
         }
 
         /* Parity stuff */
         if (cflag & PARENB) {
                 if (cflag & PARODD)
-                        LCR_change_to |= SERIAL_ODD_PARITY;
+                        new_LCR |= SERIAL_ODD_PARITY;
                 else
-                        LCR_change_to |= SERIAL_EVEN_PARITY;
+                        new_LCR |= SERIAL_EVEN_PARITY;
         }
         if (cflag & CSTOPB)
-                LCR_change_to |= SERIAL_TWO_STOPB;
+                new_LCR |= SERIAL_TWO_STOPB;
         else
-                LCR_change_to |= SERIAL_TWO_STOPB;
+                new_LCR |= SERIAL_TWO_STOPB;
 
         mydbg("%s - 4\n", __func__);
         /* Thats the LCR stuff, go ahead and set it */
         baud = tty_get_baud_rate(tty);
-        if (!baud) {
+        if (!baud)
                 /* pick a default, any default... */
                 baud = 9600;
-        }
 
         mydbg("%s - got baud = %d\n", __func__, baud);
 
@@ -1986,9 +1865,7 @@ static void qt_set_termios(struct usb_serial_port *port,
         /*
          * Set Baud rate to default and turn off (default)flow control here
          */
-        status =
-            BoxSetUart(serial, UartNumber, (unsigned short)divisor,
-                       LCR_change_to);
+        status = BoxSetUart(serial, index, (unsigned short)divisor, new_LCR);
         if (status < 0) {
                 mydbg(__FILE__ "BoxSetUart failed\n");
                 return;
@@ -2000,7 +1877,7 @@ static void qt_set_termios(struct usb_serial_port *port,
                       port->number);
 
                 /* Enable RTS/CTS flow control */
-                status = BoxSetHW_FlowCtrl(serial, UartNumber, 1);
+                status = BoxSetHW_FlowCtrl(serial, index, 1);
 
                 if (status < 0) {
                         mydbg(__FILE__ "BoxSetHW_FlowCtrl failed\n");
@@ -2011,7 +1888,7 @@ static void qt_set_termios(struct usb_serial_port *port,
                 mydbg("%s - disabling HW flow control port %d\n", __func__,
                       port->number);
 
-                status = BoxSetHW_FlowCtrl(serial, UartNumber, 0);
+                status = BoxSetHW_FlowCtrl(serial, index, 0);
                 if (status < 0) {
                         mydbg(__FILE__ "BoxSetHW_FlowCtrl failed\n");
                         return;
@@ -2025,19 +1902,20 @@ static void qt_set_termios(struct usb_serial_port *port,
                 unsigned char stop_char = STOP_CHAR(tty);
                 unsigned char start_char = START_CHAR(tty);
                 status =
-                    BoxSetSW_FlowCtrl(serial, UartNumber, stop_char,
+                    BoxSetSW_FlowCtrl(serial, index, stop_char,
                                       start_char);
                 if (status < 0)
                         mydbg(__FILE__ "BoxSetSW_FlowCtrl (enabled) failed\n");
 
         } else {
                 /* disable SW flow control */
-                status = BoxDisable_SW_FlowCtrl(serial, UartNumber);
+                status = BoxDisable_SW_FlowCtrl(serial, index);
                 if (status < 0)
                         mydbg(__FILE__ "BoxSetSW_FlowCtrl (diabling) failed\n");
 
         }
-
+        tty->termios->c_cflag &= ~CMSPAR;
+        /* FIXME: Error cases should be returning the actual bits changed only */
 }
 
 /****************************************************************************
@@ -2237,11 +2115,11 @@ static int BoxSetUart(struct usb_serial *serial, unsigned short Uart_Number,
         return result;
 }
 
-static int BoxSetHW_FlowCtrl(struct usb_serial *serial, unsigned int UartNumber,
+static int BoxSetHW_FlowCtrl(struct usb_serial *serial, unsigned int index,
                              int bSet)
 {
-        __u8 MCR_Value = 0;
-        __u8 MSR_Value = 0, MOUT_Value = 0;
+        __u8 mcr = 0;
+        __u8 msr = 0, MOUT_Value = 0;
         struct usb_serial_port *port;
         unsigned int status;
 
@@ -2249,34 +2127,34 @@ static int BoxSetHW_FlowCtrl(struct usb_serial *serial, unsigned int UartNumber,
 
         if (bSet == 1) {
                 /* flow control, box will clear RTS line to prevent remote */
-                MCR_Value = SERIAL_MCR_RTS;
+                mcr = SERIAL_MCR_RTS;
         }                       /* device from xmitting more chars */
         else {
                 /* no flow control to remote device */
-                MCR_Value = 0;
+                mcr = 0;
 
         }
-        MOUT_Value = MCR_Value << 8;
+        MOUT_Value = mcr << 8;
 
         if (bSet == 1) {
                 /* flow control, box will inhibit xmit data if CTS line is
                  * asserted */
-                MSR_Value = SERIAL_MSR_CTS;
+                msr = SERIAL_MSR_CTS;
         } else {
                 /* Box will not inhimbe xmit data due to CTS line */
-                MSR_Value = 0;
+                msr = 0;
         }
-        MOUT_Value |= MSR_Value;
+        MOUT_Value |= msr;
 
         status =
             usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
                             QT_HW_FLOW_CONTROL_MASK, 0x40, MOUT_Value,
-                            UartNumber, NULL, 0, 300);
+                            index, NULL, 0, 300);
         return status;
 
 }
 
-static int BoxSetSW_FlowCtrl(struct usb_serial *serial, __u16 UartNumber,
+static int BoxSetSW_FlowCtrl(struct usb_serial *serial, __u16 index,
                              unsigned char stop_char, unsigned char start_char)
 {
         __u16 nSWflowout;
@@ -2288,17 +2166,17 @@ static int BoxSetSW_FlowCtrl(struct usb_serial *serial, __u16 UartNumber,
         result =
             usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
                             QT_SW_FLOW_CONTROL_MASK, 0x40, nSWflowout,
-                            UartNumber, NULL, 0, 300);
+                            index, NULL, 0, 300);
         return result;
 
 }
-static int BoxDisable_SW_FlowCtrl(struct usb_serial *serial, __u16 UartNumber)
+static int BoxDisable_SW_FlowCtrl(struct usb_serial *serial, __u16 index)
 {
         int result;
 
         result =
             usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-                            QT_SW_FLOW_CONTROL_DISABLE, 0x40, 0, UartNumber,
+                            QT_SW_FLOW_CONTROL_DISABLE, 0x40, 0, index,
                             NULL, 0, 300);
         return result;
 
@@ -2307,7 +2185,7 @@ static int BoxDisable_SW_FlowCtrl(struct usb_serial *serial, __u16 UartNumber)
 static void serial_throttle(struct tty_struct *tty)
 {
         struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+            tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         mydbg("%s - port %d\n", __func__, port->number);
 
@@ -2334,7 +2212,7 @@ exit:
 static void serial_unthrottle(struct tty_struct *tty)
 {
         struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+            tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
         unsigned int result;
 
@@ -2380,20 +2258,19 @@ exit:
 
 static int serial_break(struct tty_struct *tty, int break_state)
 {
-        struct usb_serial_port *port =
-            (struct usb_serial_port *)tty->driver_data;
+        struct usb_serial_port *port = tty->driver_data;
         struct usb_serial *serial = get_usb_serial(port, __func__);
-        __u16 UartNumber, Break_Value;
+        u16 index, onoff;
         unsigned int result;
 
-        UartNumber = port->tty->index - serial->minor;
+        index = tty->index - serial->minor;
         if (!serial)
                 return -ENODEV;
 
         if (break_state == -1)
-                Break_Value = 1;
+                onoff = 1;
         else
-                Break_Value = 0;
+                onoff = 0;
 
         down(&port->sem);
 
@@ -2406,7 +2283,7 @@ static int serial_break(struct tty_struct *tty, int break_state)
 
         result =
             usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-                            QT_BREAK_CONTROL, 0x40, Break_Value, UartNumber,
+                            QT_BREAK_CONTROL, 0x40, onoff, index,
                             NULL, 0, 300);
 
 exit: