io_ti.c

linux-2.6.15.6

	if (tty && urb->actual_length) {
		usb_serial_debug_data(debug, &edge_port->port->dev, __FUNCTION__, urb->actual_length, data);

		if (edge_port->close_pending) {
			dbg ("%s - close is pending, dropping data on the floor.", __FUNCTION__);
		} else {
			edge_tty_recv(&edge_port->port->dev, tty, data, urb->actual_length);
		}
		edge_port->icount.rx += urb->actual_length;
	}

exit:
	/* continue read unless stopped */
	spin_lock(&edge_port->ep_lock);
	if (edge_port->ep_read_urb_state == EDGE_READ_URB_RUNNING) {
		urb->dev = edge_port->port->serial->dev;
		status = usb_submit_urb(urb, GFP_ATOMIC);
	} else if (edge_port->ep_read_urb_state == EDGE_READ_URB_STOPPING) {
		edge_port->ep_read_urb_state = EDGE_READ_URB_STOPPED;
	}
	spin_unlock(&edge_port->ep_lock);
	if (status)
		dev_err (&urb->dev->dev, "%s - usb_submit_urb failed with result %d\n",
			 __FUNCTION__, status);
}

static void edge_tty_recv(struct device *dev, struct tty_struct *tty, unsigned char *data, int length)
{
	int cnt;

	do {
		if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
			tty_flip_buffer_push(tty);
			if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
				dev_err(dev, "%s - dropping data, %d bytes lost\n",
					__FUNCTION__, length);
				return;
			}
		}
		cnt = min(length, TTY_FLIPBUF_SIZE - tty->flip.count);
		memcpy(tty->flip.char_buf_ptr, data, cnt);
		memset(tty->flip.flag_buf_ptr, 0, cnt);
		tty->flip.char_buf_ptr += cnt;
		tty->flip.flag_buf_ptr += cnt;
		tty->flip.count += cnt;
		data += cnt;
		length -= cnt;
	} while (length > 0);

	tty_flip_buffer_push(tty);
}

static void edge_bulk_out_callback (struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);

	dbg ("%s - port %d", __FUNCTION__, port->number);

	edge_port->ep_write_urb_in_use = 0;

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
		return;
	default:
		dev_err (&urb->dev->dev,"%s - nonzero write bulk status received: %d\n",
		     __FUNCTION__, urb->status);
	}

	/* send any buffered data */
	edge_send(port);
}

static int edge_open (struct usb_serial_port *port, struct file * filp)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	struct edgeport_serial *edge_serial;
	struct usb_device *dev;
	struct urb *urb;
	int port_number;
	int status;
	u16 open_settings;
	u8 transaction_timeout;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (edge_port == NULL)
		return -ENODEV;

	if (port->tty)
		port->tty->low_latency = low_latency;

	port_number = port->number - port->serial->minor;
	switch (port_number) {
		case 0:
			edge_port->uart_base = UMPMEM_BASE_UART1;
			edge_port->dma_address = UMPD_OEDB1_ADDRESS;
			break;
		case 1:
			edge_port->uart_base = UMPMEM_BASE_UART2;
			edge_port->dma_address = UMPD_OEDB2_ADDRESS;
			break;
		default:
			dev_err (&port->dev, "Unknown port number!!!\n");
			return -ENODEV;
	}

	dbg ("%s - port_number = %d, uart_base = %04x, dma_address = %04x",
	     __FUNCTION__, port_number, edge_port->uart_base, edge_port->dma_address);

	dev = port->serial->dev;

	memset (&(edge_port->icount), 0x00, sizeof(edge_port->icount));
	init_waitqueue_head (&edge_port->delta_msr_wait);

	/* turn off loopback */
	status = TIClearLoopBack (edge_port);
	if (status) {
		dev_err(&port->dev,"%s - cannot send clear loopback command, %d\n",
			__FUNCTION__, status);
		return status;
	}
	
	/* set up the port settings */
	edge_set_termios (port, NULL);

	/* open up the port */

	/* milliseconds to timeout for DMA transfer */
	transaction_timeout = 2;

	edge_port->ump_read_timeout = max (20, ((transaction_timeout * 3) / 2) );

	// milliseconds to timeout for DMA transfer
	open_settings = (u8)(UMP_DMA_MODE_CONTINOUS | 
			     UMP_PIPE_TRANS_TIMEOUT_ENA | 
			     (transaction_timeout << 2));

	dbg ("%s - Sending UMPC_OPEN_PORT", __FUNCTION__);

	/* Tell TI to open and start the port */
	status = TIWriteCommandSync (dev,
					UMPC_OPEN_PORT,
					(u8)(UMPM_UART1_PORT + port_number),
					open_settings,
					NULL,
					0);
	if (status) {
		dev_err(&port->dev,"%s - cannot send open command, %d\n", __FUNCTION__, status);
		return status;
	}

	/* Start the DMA? */
	status = TIWriteCommandSync (dev,
					UMPC_START_PORT,
					(u8)(UMPM_UART1_PORT + port_number),
					0,
					NULL,
					0);
	if (status) {
		dev_err(&port->dev,"%s - cannot send start DMA command, %d\n", __FUNCTION__, status);
		return status;
	}

	/* Clear TX and RX buffers in UMP */
	status = TIPurgeDataSync (port, UMP_PORT_DIR_OUT | UMP_PORT_DIR_IN);
	if (status) {
		dev_err(&port->dev,"%s - cannot send clear buffers command, %d\n", __FUNCTION__, status);
		return status;
	}

	/* Read Initial MSR */
	status = TIReadVendorRequestSync (dev,
					UMPC_READ_MSR,	// Request
					0,		// wValue
					(__u16)(UMPM_UART1_PORT + port_number),	// wIndex (Address)
					&edge_port->shadow_msr,			// TransferBuffer
					1);					// TransferBufferLength
	if (status) {
 		dev_err(&port->dev,"%s - cannot send read MSR command, %d\n", __FUNCTION__, status);
		return status;
	}

	dbg ("ShadowMSR 0x%X", edge_port->shadow_msr);
 
	/* Set Initial MCR */
	edge_port->shadow_mcr = MCR_RTS | MCR_DTR;
	dbg ("ShadowMCR 0x%X", edge_port->shadow_mcr);

	edge_serial = edge_port->edge_serial;
	if (down_interruptible(&edge_serial->es_sem))
		return -ERESTARTSYS;
	if (edge_serial->num_ports_open == 0) {
		/* we are the first port to be opened, let's post the interrupt urb */
		urb = edge_serial->serial->port[0]->interrupt_in_urb;
		if (!urb) {
			dev_err (&port->dev, "%s - no interrupt urb present, exiting\n", __FUNCTION__);
			status = -EINVAL;
			goto up_es_sem;
		}
		urb->complete = edge_interrupt_callback;
		urb->context = edge_serial;
		urb->dev = dev;
		status = usb_submit_urb (urb, GFP_KERNEL);
		if (status) {
			dev_err (&port->dev, "%s - usb_submit_urb failed with value %d\n", __FUNCTION__, status);
			goto up_es_sem;
		}
	}

	/*
	 * reset the data toggle on the bulk endpoints to work around bug in
	 * host controllers where things get out of sync some times
	 */
	usb_clear_halt (dev, port->write_urb->pipe);
	usb_clear_halt (dev, port->read_urb->pipe);

	/* start up our bulk read urb */
	urb = port->read_urb;
	if (!urb) {
		dev_err (&port->dev, "%s - no read urb present, exiting\n", __FUNCTION__);
		status = -EINVAL;
		goto unlink_int_urb;
	}
	edge_port->ep_read_urb_state = EDGE_READ_URB_RUNNING;
	urb->complete = edge_bulk_in_callback;
	urb->context = edge_port;
	urb->dev = dev;
	status = usb_submit_urb (urb, GFP_KERNEL);
	if (status) {
		dev_err (&port->dev, "%s - read bulk usb_submit_urb failed with value %d\n", __FUNCTION__, status);
		goto unlink_int_urb;
	}

	++edge_serial->num_ports_open;

	dbg("%s - exited", __FUNCTION__);

	goto up_es_sem;

unlink_int_urb:
	if (edge_port->edge_serial->num_ports_open == 0)
		usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
up_es_sem:
	up(&edge_serial->es_sem);
	return status;
}

static void edge_close (struct usb_serial_port *port, struct file *filp)
{
	struct edgeport_serial *edge_serial;
	struct edgeport_port *edge_port;
	int port_number;
	int status;

	dbg("%s - port %d", __FUNCTION__, port->number);
			 
	edge_serial = usb_get_serial_data(port->serial);
	edge_port = usb_get_serial_port_data(port);
	if ((edge_serial == NULL) || (edge_port == NULL))
		return;
	
	/* The bulkreadcompletion routine will check 
	 * this flag and dump add read data */
	edge_port->close_pending = 1;

	/* chase the port close and flush */
	TIChasePort (edge_port, (HZ*closing_wait)/100, 1);

	usb_kill_urb(port->read_urb);
	usb_kill_urb(port->write_urb);
	edge_port->ep_write_urb_in_use = 0;

	/* assuming we can still talk to the device,
	 * send a close port command to it */
	dbg("%s - send umpc_close_port", __FUNCTION__);
	port_number = port->number - port->serial->minor;
	status = TIWriteCommandSync (port->serial->dev,
				     UMPC_CLOSE_PORT,
				     (__u8)(UMPM_UART1_PORT + port_number),
				     0,
				     NULL,
				     0);
	down(&edge_serial->es_sem);
	--edge_port->edge_serial->num_ports_open;
	if (edge_port->edge_serial->num_ports_open <= 0) {
		/* last port is now closed, let's shut down our interrupt urb */
		usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
		edge_port->edge_serial->num_ports_open = 0;
	}
	up(&edge_serial->es_sem);
	edge_port->close_pending = 0;

	dbg("%s - exited", __FUNCTION__);
}

static int edge_write (struct usb_serial_port *port, const unsigned char *data, int count)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	unsigned long flags;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (count == 0) {
		dbg("%s - write request of 0 bytes", __FUNCTION__);
		return 0;
	}

	if (edge_port == NULL)
		return -ENODEV;
	if (edge_port->close_pending == 1)
		return -ENODEV;

	spin_lock_irqsave(&edge_port->ep_lock, flags);
	count = edge_buf_put(edge_port->ep_out_buf, data, count);
	spin_unlock_irqrestore(&edge_port->ep_lock, flags);

	edge_send(port);

	return count;
}

static void edge_send(struct usb_serial_port *port)
{
	int count, result;
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	struct tty_struct *tty = port->tty;
	unsigned long flags;


	dbg("%s - port %d", __FUNCTION__, port->number);

	spin_lock_irqsave(&edge_port->ep_lock, flags);

	if (edge_port->ep_write_urb_in_use) {
		spin_unlock_irqrestore(&edge_port->ep_lock, flags);
		return;
	}

	count = edge_buf_get(edge_port->ep_out_buf,
				port->write_urb->transfer_buffer,
				port->bulk_out_size);

	if (count == 0) {
		spin_unlock_irqrestore(&edge_port->ep_lock, flags);
		return;
	}

	edge_port->ep_write_urb_in_use = 1;

	spin_unlock_irqrestore(&edge_port->ep_lock, flags);

	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);

	/* set up our urb */
	usb_fill_bulk_urb (port->write_urb, port->serial->dev,
			   usb_sndbulkpipe (port->serial->dev,
					    port->bulk_out_endpointAddress),
			   port->write_urb->transfer_buffer, count,
			   edge_bulk_out_callback,
			   port);

	/* send the data out the bulk port */
	result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
	if (result) {
		dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
		edge_port->ep_write_urb_in_use = 0;
		// TODO: reschedule edge_send
	} else {
		edge_port->icount.tx += count;
	}

	/* wakeup any process waiting for writes to complete */
	/* there is now more room in the buffer for new writes */
	if (tty) {
		/* let the tty driver wakeup if it has a special write_wakeup function */
		tty_wakeup(tty);
	}
}

static int edge_write_room (struct usb_serial_port *port)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	int room = 0;
	unsigned long flags;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (edge_port == NULL)
		return -ENODEV;
	if (edge_port->close_pending == 1)
		return -ENODEV;

	spin_lock_irqsave(&edge_port->ep_lock, flags);
	room = edge_buf_space_avail(edge_port->ep_out_buf);
	spin_unlock_irqrestore(&edge_port->ep_lock, flags);

	dbg("%s - returns %d", __FUNCTION__, room);
	return room;
}

static int edge_chars_in_buffer (struct usb_serial_port *port)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	int chars = 0;
	unsigned long flags;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (edge_port == NULL)
		return -ENODEV;
	if (edge_port->close_pending == 1)
		return -ENODEV;

	spin_lock_irqsave(&edge_port->ep_lock, flags);
	chars = edge_buf_data_avail(edge_port->ep_out_buf);
	spin_unlock_irqrestore(&edge_port->ep_lock, flags);

	dbg ("%s - returns %d", __FUNCTION__, chars);
	return chars;
}

static void edge_throttle (struct usb_serial_port *port)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	struct tty_struct *tty;
	int status;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (edge_port == NULL)
		return;

	tty = port->tty;
	if (!tty) {
		dbg ("%s - no tty available", __FUNCTION__);
		return;
	}

	/* if we are implementing XON/XOFF, send the stop character */
	if (I_IXOFF(tty)) {
		unsigned char stop_char = STOP_CHAR(tty);
		status = edge_write (port, &stop_char, 1);
		if (status <= 0) {
			dev_err(&port->dev, "%s - failed to write stop character, %d\n", __FUNCTION__, status);
		}
	}

	/* if w