io_edgeport.c

linux-2.6.15.6

{
	struct serial_struct tmp;

	if (!retinfo)
		return -EFAULT;

	memset(&tmp, 0, sizeof(tmp));

	tmp.type		= PORT_16550A;
	tmp.line		= edge_port->port->serial->minor;
	tmp.port		= edge_port->port->number;
	tmp.irq			= 0;
	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
	tmp.xmit_fifo_size	= edge_port->maxTxCredits;
	tmp.baud_base		= 9600;
	tmp.close_delay		= 5*HZ;
	tmp.closing_wait	= 30*HZ;
//	tmp.custom_divisor	= state->custom_divisor;
//	tmp.hub6		= state->hub6;
//	tmp.io_type		= state->io_type;

	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
		return -EFAULT;
	return 0;
}



/*****************************************************************************
 * SerialIoctl
 *	this function handles any ioctl calls to the driver
 *****************************************************************************/
static int edge_ioctl (struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg)
{
	DEFINE_WAIT(wait);
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	struct async_icount cnow;
	struct async_icount cprev;
	struct serial_icounter_struct icount;

	dbg("%s - port %d, cmd = 0x%x", __FUNCTION__, port->number, cmd);

	switch (cmd) {
		// return number of bytes available
		case TIOCINQ:
			dbg("%s (%d) TIOCINQ", __FUNCTION__,  port->number);
			return get_number_bytes_avail(edge_port, (unsigned int __user *) arg);
			break;

		case TIOCSERGETLSR:
			dbg("%s (%d) TIOCSERGETLSR", __FUNCTION__,  port->number);
			return get_lsr_info(edge_port, (unsigned int __user *) arg);
			return 0;

		case TIOCGSERIAL:
			dbg("%s (%d) TIOCGSERIAL", __FUNCTION__,  port->number);
			return get_serial_info(edge_port, (struct serial_struct __user *) arg);

		case TIOCSSERIAL:
			dbg("%s (%d) TIOCSSERIAL", __FUNCTION__,  port->number);
			break;

		case TIOCMIWAIT:
			dbg("%s (%d) TIOCMIWAIT", __FUNCTION__,  port->number);
			cprev = edge_port->icount;
			while (1) {
				prepare_to_wait(&edge_port->delta_msr_wait, &wait, TASK_INTERRUPTIBLE);
				schedule();
				finish_wait(&edge_port->delta_msr_wait, &wait);
				/* see if a signal did it */
				if (signal_pending(current))
					return -ERESTARTSYS;
				cnow = edge_port->icount;
				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
					return -EIO; /* no change => error */
				if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
				    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
				    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
				    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
					return 0;
				}
				cprev = cnow;
			}
			/* NOTREACHED */
			break;

		case TIOCGICOUNT:
			cnow = edge_port->icount;
			memset(&icount, 0, sizeof(icount));
			icount.cts = cnow.cts;
			icount.dsr = cnow.dsr;
			icount.rng = cnow.rng;
			icount.dcd = cnow.dcd;
			icount.rx = cnow.rx;
			icount.tx = cnow.tx;
			icount.frame = cnow.frame;
			icount.overrun = cnow.overrun;
			icount.parity = cnow.parity;
			icount.brk = cnow.brk;
			icount.buf_overrun = cnow.buf_overrun;

			dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __FUNCTION__,  port->number, icount.rx, icount.tx );
			if (copy_to_user((void __user *)arg, &icount, sizeof(icount)))
				return -EFAULT;
			return 0;
	}

	return -ENOIOCTLCMD;
}


/*****************************************************************************
 * SerialBreak
 *	this function sends a break to the port
 *****************************************************************************/
static void edge_break (struct usb_serial_port *port, int break_state)
{
	struct edgeport_port *edge_port = usb_get_serial_port_data(port);
	int status;

	/* flush and chase */
	edge_port->chaseResponsePending = TRUE;

	dbg("%s - Sending IOSP_CMD_CHASE_PORT", __FUNCTION__);
	status = send_iosp_ext_cmd (edge_port, IOSP_CMD_CHASE_PORT, 0);
	if (status == 0) {
		// block until chase finished
		block_until_chase_response(edge_port);
	} else {
		edge_port->chaseResponsePending = FALSE;
	}

	if (break_state == -1) {
		dbg("%s - Sending IOSP_CMD_SET_BREAK", __FUNCTION__);
		status = send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_BREAK, 0);
	} else {
		dbg("%s - Sending IOSP_CMD_CLEAR_BREAK", __FUNCTION__);
		status = send_iosp_ext_cmd (edge_port, IOSP_CMD_CLEAR_BREAK, 0);
	}
	if (status) {
		dbg("%s - error sending break set/clear command.", __FUNCTION__);
	}

	return;
}


/*****************************************************************************
 * process_rcvd_data
 *	this function handles the data received on the bulk in pipe.
 *****************************************************************************/
static void process_rcvd_data (struct edgeport_serial *edge_serial, unsigned char * buffer, __u16 bufferLength)
{
	struct usb_serial_port *port;
	struct edgeport_port *edge_port;
	struct tty_struct *tty;
	__u16 lastBufferLength;
	__u16 rxLen;

	dbg("%s", __FUNCTION__);

	lastBufferLength = bufferLength + 1;

	while (bufferLength > 0) {
		/* failsafe incase we get a message that we don't understand */
		if (lastBufferLength == bufferLength) {
			dbg("%s - stuck in loop, exiting it.", __FUNCTION__);
			break;
		}
		lastBufferLength = bufferLength;

		switch (edge_serial->rxState) {
			case EXPECT_HDR1:
				edge_serial->rxHeader1 = *buffer;
				++buffer;
				--bufferLength;

				if (bufferLength == 0) {
					edge_serial->rxState = EXPECT_HDR2;
					break;
				}
				/* otherwise, drop on through */

			case EXPECT_HDR2:
				edge_serial->rxHeader2 = *buffer;
				++buffer;
				--bufferLength;

				dbg("%s - Hdr1=%02X Hdr2=%02X", __FUNCTION__, edge_serial->rxHeader1, edge_serial->rxHeader2);

				// Process depending on whether this header is
				// data or status

				if (IS_CMD_STAT_HDR(edge_serial->rxHeader1)) {
					// Decode this status header and goto EXPECT_HDR1 (if we
					// can process the status with only 2 bytes), or goto
					// EXPECT_HDR3 to get the third byte.

					edge_serial->rxPort       = IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
					edge_serial->rxStatusCode = IOSP_GET_STATUS_CODE(edge_serial->rxHeader1);

					if (!IOSP_STATUS_IS_2BYTE(edge_serial->rxStatusCode)) {
						// This status needs additional bytes. Save what we have
						// and then wait for more data.
						edge_serial->rxStatusParam = edge_serial->rxHeader2;

						edge_serial->rxState = EXPECT_HDR3;
						break;
					}

					// We have all the header bytes, process the status now
					process_rcvd_status (edge_serial, edge_serial->rxHeader2, 0);
					edge_serial->rxState = EXPECT_HDR1;
					break;
				} else {
					edge_serial->rxPort = IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
					edge_serial->rxBytesRemaining = IOSP_GET_HDR_DATA_LEN(edge_serial->rxHeader1, edge_serial->rxHeader2);

					dbg("%s - Data for Port %u Len %u", __FUNCTION__, edge_serial->rxPort, edge_serial->rxBytesRemaining);

					//ASSERT( DevExt->RxPort < DevExt->NumPorts );
					//ASSERT( DevExt->RxBytesRemaining < IOSP_MAX_DATA_LENGTH );

					if (bufferLength == 0 ) {
						edge_serial->rxState = EXPECT_DATA;
						break;
					}
					// Else, drop through
				}

			case EXPECT_DATA:	// Expect data

				if (bufferLength < edge_serial->rxBytesRemaining) {
					rxLen = bufferLength;
					edge_serial->rxState = EXPECT_DATA;	// Expect data to start next buffer
				} else {
					// BufLen >= RxBytesRemaining
					rxLen = edge_serial->rxBytesRemaining;
					edge_serial->rxState = EXPECT_HDR1;	// Start another header next time
				}

				bufferLength -= rxLen;
				edge_serial->rxBytesRemaining -= rxLen;

				/* spit this data back into the tty driver if this port is open */
				if (rxLen) {
					port = edge_serial->serial->port[edge_serial->rxPort];
					edge_port = usb_get_serial_port_data(port);
					if (edge_port->open) {
						tty = edge_port->port->tty;
						if (tty) {
							dbg("%s - Sending %d bytes to TTY for port %d", __FUNCTION__, rxLen, edge_serial->rxPort);
							edge_tty_recv(&edge_serial->serial->dev->dev, tty, buffer, rxLen);
						}
						edge_port->icount.rx += rxLen;
					}
					buffer += rxLen;
				}

				break;

			case EXPECT_HDR3:			// Expect 3rd byte of status header
				edge_serial->rxHeader3 = *buffer;
				++buffer;
				--bufferLength;

				// We have all the header bytes, process the status now
				process_rcvd_status (edge_serial, edge_serial->rxStatusParam, edge_serial->rxHeader3);
				edge_serial->rxState = EXPECT_HDR1;
				break;

		}
	}
}


/*****************************************************************************
 * process_rcvd_status
 *	this function handles the any status messages received on the bulk in pipe.
 *****************************************************************************/
static void process_rcvd_status (struct edgeport_serial *edge_serial, __u8 byte2, __u8 byte3)
{
	struct usb_serial_port *port;
	struct edgeport_port *edge_port;
	__u8 code = edge_serial->rxStatusCode;

	/* switch the port pointer to the one being currently talked about */
	port = edge_serial->serial->port[edge_serial->rxPort];
	edge_port = usb_get_serial_port_data(port);
	if (edge_port == NULL) {
		dev_err(&edge_serial->serial->dev->dev, "%s - edge_port == NULL for port %d\n", __FUNCTION__, edge_serial->rxPort);
		return;
	}

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

	if (code == IOSP_EXT_STATUS) {
		switch (byte2) {
			case IOSP_EXT_STATUS_CHASE_RSP:
				// we want to do EXT status regardless of port open/closed 
				dbg("%s - Port %u EXT CHASE_RSP Data = %02x", __FUNCTION__, edge_serial->rxPort, byte3 );
				// Currently, the only EXT_STATUS is Chase, so process here instead of one more call
				// to one more subroutine. If/when more EXT_STATUS, there'll be more work to do.
				// Also, we currently clear flag and close the port regardless of content of above's Byte3.
				// We could choose to do something else when Byte3 says Timeout on Chase from Edgeport,
				// like wait longer in block_until_chase_response, but for now we don't. 
				edge_port->chaseResponsePending = FALSE;
				wake_up (&edge_port->wait_chase);
				return;

			case IOSP_EXT_STATUS_RX_CHECK_RSP:
				dbg("%s ========== Port %u CHECK_RSP Sequence = %02x =============\n", __FUNCTION__, edge_serial->rxPort, byte3 );
				//Port->RxCheckRsp = TRUE;
				return;
		}
	}

	if (code == IOSP_STATUS_OPEN_RSP) {
		edge_port->txCredits = GET_TX_BUFFER_SIZE(byte3);
		edge_port->maxTxCredits = edge_port->txCredits;
		dbg("%s - Port %u Open Response Inital MSR = %02x TxBufferSize = %d", __FUNCTION__, edge_serial->rxPort, byte2, edge_port->txCredits);
		handle_new_msr (edge_port, byte2);

		/* send the current line settings to the port so we are in sync with any further termios calls */
		if (edge_port->port->tty)
			change_port_settings (edge_port, edge_port->port->tty->termios);

		/* we have completed the open */
		edge_port->openPending = FALSE;
		edge_port->open = TRUE;
		wake_up(&edge_port->wait_open);
		return;
	}

	// If port is closed, silently discard all rcvd status. We can
	// have cases where buffered status is received AFTER the close
	// port command is sent to the Edgeport.
	if ((!edge_port->open ) || (edge_port->closePending)) {
		return;
	}

	switch (code) {
		// Not currently sent by Edgeport
		case IOSP_STATUS_LSR:
			dbg("%s - Port %u LSR Status = %02x", __FUNCTION__, edge_serial->rxPort, byte2);
			handle_new_lsr (edge_port, FALSE, byte2, 0);
			break;

		case IOSP_STATUS_LSR_DATA:
			dbg("%s - Port %u LSR Status = %02x, Data = %02x", __FUNCTION__, edge_serial->rxPort, byte2, byte3);
			// byte2 is LSR Register
			// byte3 is broken data byte
			handle_new_lsr (edge_port, TRUE, byte2, byte3);
			break;
			//
			//	case IOSP_EXT_4_STATUS:
			//		dbg("%s - Port %u LSR Status = %02x Data = %02x", __FUNCTION__, edge_serial->rxPort, byte2, byte3);
			//		break;
			//
		case IOSP_STATUS_MSR:
			dbg("%s - Port %u MSR Status = %02x", __FUNCTION__, edge_serial->rxPort, byte2);

			// Process this new modem status and generate appropriate
			// events, etc, based on the new status. This routine
			// also saves the MSR in Port->ShadowMsr.
			handle_new_msr(edge_port, byte2);
			break;

		default:
			dbg("%s - Unrecognized IOSP status code %u\n", __FUNCTION__, code);
			break;
	}

	return;
}


/*****************************************************************************
 * edge_tty_recv
 *	this function passes data on to the tty flip buffer
 *****************************************************************************/
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;
			}