USB: serial: ir_usb: Clean up the worst of it, remove exciting 'crash on open' feature

- Drivers don't call ldisc termios methods. They certainly don't call
them the way this one does - remove wrong call
- The tty buffer code isn't designed to be abused from IRQ handlers and
the new buffering removes the need for the uglies involved - fix them
- Style
- Remove incorrect baud and change handling for termios changes

The driver now has some style, but not a lot - it goes insane if you have
two dongles for example as it continues to use global variables for per
dongle state. That bit isn't my problem.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 60 insertions, 82 deletions

diff --git a/drivers/usb/serial/ir-usb.c b/drivers/usb/serial/ir-usb.c
index 8cec5e520d9..5ab6a0c5ac5 100644
--- a/drivers/usb/serial/ir-usb.c
+++ b/drivers/usb/serial/ir-usb.c
@@ -21,6 +21,10 @@
  *
  * See Documentation/usb/usb-serial.txt for more information on using this driver
  *
+ * 2007_Jun_21  Alan Cox <alan@redhat.com>
+ *      Minimal cleanups for some of the driver problens and tty layer abuse.
+ *      Still needs fixing to allow multiple dongles.
+ *
  * 2002_Mar_07  greg kh
  *      moved some needed structures and #define values from the
  *      net/irda/irda-usb.h file into our file, as we don't want to depend on
@@ -109,6 +113,7 @@ static void ir_write_bulk_callback (struct urb *urb);
 static void ir_read_bulk_callback (struct urb *urb);
 static void ir_set_termios (struct usb_serial_port *port, struct ktermios *old_termios);
 
+/* Not that this lot means you can only have one per system */
 static u8 ir_baud = 0;
 static u8 ir_xbof = 0;
 static u8 ir_add_bof = 0;
@@ -446,22 +451,12 @@ static void ir_read_bulk_callback (struct urb *urb)
                                 urb->actual_length,
                                 data);
 
-                        /*
-                         * Bypass flip-buffers, and feed the ldisc directly
-                         * due to our potentially large buffer size.  Since we
-                         * used to set low_latency, this is exactly what the
-                         * tty layer did anyway :)
-                         */
                         tty = port->tty;
 
-                        /*
-                         *      FIXME: must not do this in IRQ context
-                         */
-                        tty->ldisc.receive_buf(
-                                tty,
-                                data+1,
-                                NULL,
-                                urb->actual_length-1);
+                        if (tty_buffer_request_room(tty, urb->actual_length - 1)) {
+                                tty_insert_flip_string(tty, data+1, urb->actual_length - 1);
+                                tty_flip_buffer_push(tty);
+                        }
 
                         /*
                          * No break here.
@@ -503,8 +498,9 @@ static void ir_read_bulk_callback (struct urb *urb)
 static void ir_set_termios (struct usb_serial_port *port, struct ktermios *old_termios)
 {
         unsigned char *transfer_buffer;
-        unsigned int cflag;
         int result;
+        speed_t baud;
+        int ir_baud;
 
         dbg("%s - port %d", __FUNCTION__, port->number);
 
@@ -513,77 +509,59 @@ static void ir_set_termios (struct usb_serial_port *port, struct ktermios *old_t
                 return;
         }
 
-        cflag = port->tty->termios->c_cflag;
-        /* check that they really want us to change something */
-        if (old_termios) {
-                if ((cflag == old_termios->c_cflag) &&
-                    (RELEVANT_IFLAG(port->tty->termios->c_iflag) == RELEVANT_IFLAG(old_termios->c_iflag))) {
-                        dbg("%s - nothing to change...", __FUNCTION__);
-                        return;
-                }
+        baud = tty_get_baud_rate(port->tty);
+
+        /*
+         * FIXME, we should compare the baud request against the
+         * capability stated in the IR header that we got in the
+         * startup function.
+         */
+
+        switch (baud) {
+                case 2400:      ir_baud = SPEED_2400; break;
+                case 9600:      ir_baud = SPEED_9600; break;
+                case 19200:     ir_baud = SPEED_19200; break;
+                case 38400:     ir_baud = SPEED_38400; break;
+                case 57600:     ir_baud = SPEED_57600; break;
+                case 115200:    ir_baud = SPEED_115200; break;
+                case 576000:    ir_baud = SPEED_576000; break;
+                case 1152000:   ir_baud = SPEED_1152000; break;
+                case 4000000:   ir_baud = SPEED_4000000; break;
+                        break;
+                default:
+                        ir_baud = SPEED_9600;
+                        baud = 9600;
+                        /* And once the new tty stuff is all done we need to
+                           call back to correct the baud bits */
         }
 
-        /* All we can change is the baud rate */
-        if (cflag & CBAUD) {
-
-                dbg ("%s - asking for baud %d",
-                        __FUNCTION__,
-                        tty_get_baud_rate(port->tty));
-
-                /* 
-                 * FIXME, we should compare the baud request against the
-                 * capability stated in the IR header that we got in the
-                 * startup function.
-                 */
-                switch (cflag & CBAUD) {
-                        case B2400:    ir_baud = SPEED_2400;    break;
-                        default:
-                        case B9600:    ir_baud = SPEED_9600;    break;
-                        case B19200:   ir_baud = SPEED_19200;   break;
-                        case B38400:   ir_baud = SPEED_38400;   break;
-                        case B57600:   ir_baud = SPEED_57600;   break;
-                        case B115200:  ir_baud = SPEED_115200;  break;
-                        case B576000:  ir_baud = SPEED_576000;  break;
-                        case B1152000: ir_baud = SPEED_1152000; break;
-#ifdef B4000000
-                        case B4000000: ir_baud = SPEED_4000000; break;
-#endif
-                }
+        if (xbof == -1)
+                ir_xbof = ir_xbof_change(ir_add_bof);
+        else
+                ir_xbof = ir_xbof_change(xbof) ;
 
-                if (xbof == -1) {
-                        ir_xbof = ir_xbof_change(ir_add_bof);
-                } else {
-                        ir_xbof = ir_xbof_change(xbof) ;
-                }
+        /* FIXME need to check to see if our write urb is busy right
+         * now, or use a urb pool.
+         *
+         * send the baud change out on an "empty" data packet
+         */
+        transfer_buffer = port->write_urb->transfer_buffer;
+        *transfer_buffer = ir_xbof | ir_baud;
 
-                /* Notify the tty driver that the termios have changed. */
-                port->tty->ldisc.set_termios(port->tty, NULL);
-
-                /* FIXME need to check to see if our write urb is busy right
-                 * now, or use a urb pool.
-                 *
-                 * send the baud change out on an "empty" data packet
-                 */
-                transfer_buffer = port->write_urb->transfer_buffer;
-                *transfer_buffer = ir_xbof | ir_baud;
-
-                usb_fill_bulk_urb (
-                        port->write_urb,
-                        port->serial->dev,
-                        usb_sndbulkpipe(port->serial->dev,
-                                port->bulk_out_endpointAddress),
-                        port->write_urb->transfer_buffer,
-                        1,
-                        ir_write_bulk_callback,
-                        port);
-
-                port->write_urb->transfer_flags = URB_ZERO_PACKET;
-
-                result = usb_submit_urb (port->write_urb, GFP_KERNEL);
-                if (result)
-                        dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
-        }
-        return;
+        usb_fill_bulk_urb (
+                port->write_urb,
+                port->serial->dev,
+                usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
+                port->write_urb->transfer_buffer,
+                1,
+                ir_write_bulk_callback,
+                port);
+
+        port->write_urb->transfer_flags = URB_ZERO_PACKET;
+
+        result = usb_submit_urb (port->write_urb, GFP_KERNEL);
+        if (result)
+                dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 }