io_ti.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

{
	int port_number = port->port->number - port->port->serial->minor;

	dbg ("%s", __FUNCTION__);

	return TIWriteCommandSync (port->port->serial->dev,
				UMPC_SET_CLR_LOOPBACK,
				(__u8)(UMPM_UART1_PORT + port_number),
				0,	/* clear */
				NULL,
				0);
}

static int TISetBreak (struct edgeport_port *port)
{
	int port_number = port->port->number - port->port->serial->minor;

	dbg ("%s", __FUNCTION__);

	return TIWriteCommandSync (port->port->serial->dev,
				UMPC_SET_CLR_BREAK,
				(__u8)(UMPM_UART1_PORT + port_number),
				1,	/* set */
				NULL,
				0);
}

static int TIClearBreak (struct edgeport_port *port)
{
	int port_number = port->port->number - port->port->serial->minor;

	dbg ("%s", __FUNCTION__);

	return TIWriteCommandSync (port->port->serial->dev,
				UMPC_SET_CLR_BREAK,
				(__u8)(UMPM_UART1_PORT + port_number),
				0,	/* clear */
				NULL,
				0);
}

static int TIRestoreMCR (struct edgeport_port *port, __u8 mcr)
{
	int status = 0;

	dbg ("%s - %x", __FUNCTION__, mcr);

	if (mcr & MCR_DTR)
		status = TISetDtr (port);
	else
		status = TIClearDtr (port);

	if (status)
		return status;

	if (mcr & MCR_RTS)
		status = TISetRts (port);
	else
		status = TIClearRts (port);

	if (status)
		return status;

	if (mcr & MCR_LOOPBACK)
		status = TISetLoopBack (port);
	else
		status = TIClearLoopBack (port);

	return status;
}



/* Convert TI LSR to standard UART flags */
static __u8 MapLineStatus (__u8 ti_lsr)
{
	__u8 lsr = 0;

#define MAP_FLAG(flagUmp, flagUart)    \
	if (ti_lsr & flagUmp) lsr |= flagUart;

	MAP_FLAG(UMP_UART_LSR_OV_MASK, LSR_OVER_ERR)	/* overrun */
	MAP_FLAG(UMP_UART_LSR_PE_MASK, LSR_PAR_ERR)	/* parity error */
	MAP_FLAG(UMP_UART_LSR_FE_MASK, LSR_FRM_ERR)	/* framing error */
	MAP_FLAG(UMP_UART_LSR_BR_MASK, LSR_BREAK)	/* break detected */
	MAP_FLAG(UMP_UART_LSR_RX_MASK, LSR_RX_AVAIL)	/* receive data available */
	MAP_FLAG(UMP_UART_LSR_TX_MASK, LSR_TX_EMPTY)	/* transmit holding register empty */

#undef MAP_FLAG

	return lsr;
}

static void handle_new_msr (struct edgeport_port *edge_port, __u8 msr)
{
	struct async_icount *icount;

	dbg ("%s - %02x", __FUNCTION__, msr);

	if (msr & (EDGEPORT_MSR_DELTA_CTS | EDGEPORT_MSR_DELTA_DSR | EDGEPORT_MSR_DELTA_RI | EDGEPORT_MSR_DELTA_CD)) {
		icount = &edge_port->icount;

		/* update input line counters */
		if (msr & EDGEPORT_MSR_DELTA_CTS)
			icount->cts++;
		if (msr & EDGEPORT_MSR_DELTA_DSR)
			icount->dsr++;
		if (msr & EDGEPORT_MSR_DELTA_CD)
			icount->dcd++;
		if (msr & EDGEPORT_MSR_DELTA_RI)
			icount->rng++;
		wake_up_interruptible (&edge_port->delta_msr_wait);
	}

	/* Save the new modem status */
	edge_port->shadow_msr = msr & 0xf0;

	return;
}

static void handle_new_lsr (struct edgeport_port *edge_port, int lsr_data, __u8 lsr, __u8 data)
{
	struct async_icount *icount;
	__u8 new_lsr = (__u8)(lsr & (__u8)(LSR_OVER_ERR | LSR_PAR_ERR | LSR_FRM_ERR | LSR_BREAK));

	dbg ("%s - %02x", __FUNCTION__, new_lsr);

	edge_port->shadow_lsr = lsr;

	if (new_lsr & LSR_BREAK) {
		/*
		 * Parity and Framing errors only count if they
		 * occur exclusive of a break being received.
		 */
		new_lsr &= (__u8)(LSR_OVER_ERR | LSR_BREAK);
	}

	/* Place LSR data byte into Rx buffer */
	if (lsr_data && edge_port->port->tty) {
		tty_insert_flip_char(edge_port->port->tty, data, 0);
		tty_flip_buffer_push(edge_port->port->tty);
	}

	/* update input line counters */
	icount = &edge_port->icount;
	if (new_lsr & LSR_BREAK)
		icount->brk++;
	if (new_lsr & LSR_OVER_ERR)
		icount->overrun++;
	if (new_lsr & LSR_PAR_ERR)
		icount->parity++;
	if (new_lsr & LSR_FRM_ERR)
		icount->frame++;
}


static void edge_interrupt_callback (struct urb *urb)
{
	struct edgeport_serial	*edge_serial = (struct edgeport_serial *)urb->context;
	struct usb_serial_port *port;
	struct edgeport_port *edge_port;
	unsigned char *data = urb->transfer_buffer;
	int length = urb->actual_length;
	int port_number;
	int function;
	__u8 lsr;
	__u8 msr;

	dbg("%s", __FUNCTION__);

	if (serial_paranoia_check (edge_serial->serial, __FUNCTION__)) {
		return;
	}

	if (urb->status) {
		dbg("%s - nonzero control read status received: %d", __FUNCTION__, urb->status);
		return;
	}

	if (!length) {
		dbg ("%s - no data in urb", __FUNCTION__);
		return;
	}
		
	usb_serial_debug_data (__FILE__, __FUNCTION__, length, data);
		
	if (length != 2) {
		dbg ("%s - expecting packet of size 2, got %d", __FUNCTION__, length);
		return;
	}

	port_number = TIUMP_GET_PORT_FROM_CODE (data[0]);
	function    = TIUMP_GET_FUNC_FROM_CODE (data[0]);
	dbg ("%s - port_number %d, function %d, info 0x%x",
	     __FUNCTION__, port_number, function, data[1]);
	port = &edge_serial->serial->port[port_number];
	if (port_paranoia_check (port, __FUNCTION__)) {
		dbg ("%s - change found for port that is not present",
		     __FUNCTION__);
		return;
	}
	edge_port = port->private;
	if (!edge_port) {
		dbg ("%s - edge_port not found", __FUNCTION__);
		return;
	}
	switch (function) {
	case TIUMP_INTERRUPT_CODE_LSR:
		lsr = MapLineStatus(data[1]);
		if (lsr & UMP_UART_LSR_DATA_MASK) {
			/* Save the LSR event for bulk read completion routine */
			dbg ("%s - LSR Event Port %u LSR Status = %02x",
			     __FUNCTION__, port_number, lsr);
			edge_port->lsr_event = 1;
			edge_port->lsr_mask = lsr;
		} else {
			dbg ("%s - ===== Port %d LSR Status = %02x ======",
			     __FUNCTION__, port_number, lsr);
			handle_new_lsr (edge_port, 0, lsr, 0);
		}
		break;

	case TIUMP_INTERRUPT_CODE_MSR:	// MSR
		/* Copy MSR from UMP */
		msr = data[1];
		dbg ("%s - ===== Port %u MSR Status = %02x ======\n",
		     __FUNCTION__, port_number, msr);
		handle_new_msr (edge_port, msr);
		break;

	default:
		err ("%s - Unknown Interrupt code from UMP %x\n",
		     __FUNCTION__, data[1]);
		break;
		
	}
}

static void edge_bulk_in_callback (struct urb *urb)
{
	struct edgeport_port *edge_port = (struct edgeport_port *)urb->context;
	unsigned char *data = urb->transfer_buffer;
	struct tty_struct *tty;
	int status;
	int i;
	int port_number;

	dbg("%s", __FUNCTION__);

	if (port_paranoia_check (edge_port->port, __FUNCTION__))
		return;

	if (urb->status) {
		dbg ("%s - nonzero read bulk status received: %d",
		     __FUNCTION__, urb->status);

		if (urb->status == -EPIPE) {
			/* clear any problem that might have happened on this pipe */
			usb_clear_halt (edge_port->port->serial->dev, urb->pipe);
			goto exit;
		}
		return;
	}

	port_number = edge_port->port->number - edge_port->port->serial->minor;

	if (edge_port->lsr_event) {
		edge_port->lsr_event = 0;
		dbg ("%s ===== Port %u LSR Status = %02x, Data = %02x ======",
		     __FUNCTION__, port_number, edge_port->lsr_mask, *data);
		handle_new_lsr (edge_port, 1, edge_port->lsr_mask, *data);
		/* Adjust buffer length/pointer */
		--urb->actual_length;
		++data;
	}

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

		if (edge_port->close_pending) {
			dbg ("%s - close is pending, dropping data on the floor.", __FUNCTION__);
		} else {
			for (i = 0; i < urb->actual_length ; ++i) {
				/* if we insert more than TTY_FLIPBUF_SIZE characters,
				 * we drop them. */
				if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
					tty_flip_buffer_push(tty);
				}
				/* this doesn't actually push the data through unless
				 * tty->low_latency is set */
				tty_insert_flip_char(tty, data[i], 0);
			}
			tty_flip_buffer_push(tty);
		}
		edge_port->icount.rx += urb->actual_length;
	}

exit:
	/* continue always trying to read */
	urb->dev = edge_port->port->serial->dev;
	status = usb_submit_urb (urb);
	if (status)
		err ("%s - usb_submit_urb failed with result %d",
		     __FUNCTION__, status);
}

static void edge_bulk_out_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
	struct tty_struct *tty;

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

	if (!serial) {
		dbg ("%s - bad serial pointer, exiting", __FUNCTION__);
		return;
	}

	if (urb->status) {
		dbg ("%s - nonzero write bulk status received: %d",
		     __FUNCTION__, urb->status);

		if (urb->status == -EPIPE) {
			/* clear any problem that might have happened on this pipe */
			usb_clear_halt (serial->dev, urb->pipe);
		}
		return;
	}

	tty = port->tty;
	if (tty) {
		/* let the tty driver wakeup if it has a special write_wakeup function */
		if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) {
			(tty->ldisc.write_wakeup)(tty);
		}

		/* tell the tty driver that something has changed */
		wake_up_interruptible(&tty->write_wait);
	}
}

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

	if (port_paranoia_check (port, __FUNCTION__))
		return -ENODEV;
	
	dbg("%s - port %d", __FUNCTION__, port->number);

	if (edge_port == NULL)
		return -ENODEV;

	/* 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 = 1;

	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:
			err ("Unknown port number!!!");
			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)
		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)
		return status;

	/* Start the DMA? */
	status = TIWriteCommandSync (dev,
					UMPC_START_PORT,
					(u8)(UMPM_UART1_PORT + port_number),
					0,
					NULL,
					0);
	if (status)
		return status;

	/* Clear TX and RX buffers in UMP */
	status = TIPurgeDataSync (port, UMP_PORT_DIR_OUT | UMP_PORT_DIR_IN);
	if (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)
		return status;

	dbg ("ShadowMSR 0x%X", edge_port->shadow_msr);
 
	edge_serial = edge_port->edge_serial;
	if (edge_serial->num_ports_open == 0) {
		dbg ("%s - setting up bulk in urb", __FUNCTION__);
		/* 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) {
			err ("%s - no interrupt urb present, exiting", __FUNCTION__);
			return -EINVAL;
		}
		urb->complete = edge_interrupt_callback;
		urb->context = edge_serial;
		urb->dev = dev;
		status = usb_submit_urb (urb);
		if (status) {
			err ("%s - usb_submit_urb failed with value %d", __FUNCTION__, status);
			return status;
		}
	}

	/*
	 * 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) {
		err ("%s - no read urb present, exiting", __FUNCTION__);
		return -EINVAL;
	}
	urb->complete = edge_bulk_in_callback;
	urb->context = edge_port;