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v6.8
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
  4 *
  5 *   Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
  6 *
 
 
 
 
 
  7 * This program is largely derived from the Belkin USB Serial Adapter Driver
  8 * (see belkin_sa.[ch]). All of the information about the device was acquired
  9 * by using SniffUSB on Windows98. For technical details see mct_u232.h.
 10 *
 11 * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
 12 * do the reverse engineering and how to write a USB serial device driver.
 13 *
 14 * TO BE DONE, TO BE CHECKED:
 15 *   DTR/RTS signal handling may be incomplete or incorrect. I have mainly
 16 *   implemented what I have seen with SniffUSB or found in belkin_sa.c.
 17 *   For further TODOs check also belkin_sa.c.
 18 */
 19
 20#include <linux/kernel.h>
 21#include <linux/errno.h>
 
 22#include <linux/slab.h>
 23#include <linux/tty.h>
 24#include <linux/tty_driver.h>
 25#include <linux/tty_flip.h>
 26#include <linux/module.h>
 27#include <linux/spinlock.h>
 28#include <linux/uaccess.h>
 29#include <asm/unaligned.h>
 30#include <linux/usb.h>
 31#include <linux/usb/serial.h>
 32#include <linux/serial.h>
 
 33#include "mct_u232.h"
 34
 
 
 
 
 35#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
 36#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
 37
 
 
 38/*
 39 * Function prototypes
 40 */
 41static int  mct_u232_port_probe(struct usb_serial_port *port);
 42static void mct_u232_port_remove(struct usb_serial_port *remove);
 43static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
 44static void mct_u232_close(struct usb_serial_port *port);
 45static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
 46static void mct_u232_read_int_callback(struct urb *urb);
 47static void mct_u232_set_termios(struct tty_struct *tty,
 48				 struct usb_serial_port *port,
 49				 const struct ktermios *old_termios);
 50static int  mct_u232_break_ctl(struct tty_struct *tty, int break_state);
 51static int  mct_u232_tiocmget(struct tty_struct *tty);
 52static int  mct_u232_tiocmset(struct tty_struct *tty,
 53			unsigned int set, unsigned int clear);
 
 
 
 
 54static void mct_u232_throttle(struct tty_struct *tty);
 55static void mct_u232_unthrottle(struct tty_struct *tty);
 56
 57
 58/*
 59 * All of the device info needed for the MCT USB-RS232 converter.
 60 */
 61static const struct usb_device_id id_table[] = {
 62	{ USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
 63	{ USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
 64	{ USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
 65	{ USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
 66	{ }		/* Terminating entry */
 67};
 68MODULE_DEVICE_TABLE(usb, id_table);
 69
 70static struct usb_serial_driver mct_u232_device = {
 71	.driver = {
 72		.owner =	THIS_MODULE,
 73		.name =		"mct_u232",
 74	},
 75	.description =	     "MCT U232",
 76	.id_table =	     id_table,
 77	.num_ports =	     1,
 78	.open =		     mct_u232_open,
 79	.close =	     mct_u232_close,
 80	.dtr_rts =	     mct_u232_dtr_rts,
 81	.throttle =	     mct_u232_throttle,
 82	.unthrottle =	     mct_u232_unthrottle,
 83	.read_int_callback = mct_u232_read_int_callback,
 84	.set_termios =	     mct_u232_set_termios,
 85	.break_ctl =	     mct_u232_break_ctl,
 86	.tiocmget =	     mct_u232_tiocmget,
 87	.tiocmset =	     mct_u232_tiocmset,
 88	.tiocmiwait =        usb_serial_generic_tiocmiwait,
 89	.port_probe =        mct_u232_port_probe,
 90	.port_remove =       mct_u232_port_remove,
 91	.get_icount =        usb_serial_generic_get_icount,
 92};
 93
 94static struct usb_serial_driver * const serial_drivers[] = {
 95	&mct_u232_device, NULL
 96};
 97
 98struct mct_u232_private {
 99	struct urb *read_urb;
100	spinlock_t lock;
101	unsigned int	     control_state; /* Modem Line Setting (TIOCM) */
102	unsigned char        last_lcr;      /* Line Control Register */
103	unsigned char	     last_lsr;      /* Line Status Register */
104	unsigned char	     last_msr;      /* Modem Status Register */
105	unsigned int	     rx_flags;      /* Throttling flags */
 
 
 
106};
107
108#define THROTTLED		0x01
109
110/*
111 * Handle vendor specific USB requests
112 */
113
114#define WDR_TIMEOUT 5000 /* default urb timeout */
115
116/*
117 * Later day 2.6.0-test kernels have new baud rates like B230400 which
118 * we do not know how to support. We ignore them for the moment.
119 */
120static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
121					speed_t value, speed_t *result)
122{
123	*result = value;
124
125	if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
126		|| le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
127		switch (value) {
128		case 300:
129			return 0x01;
130		case 600:
131			return 0x02; /* this one not tested */
132		case 1200:
133			return 0x03;
134		case 2400:
135			return 0x04;
136		case 4800:
137			return 0x06;
138		case 9600:
139			return 0x08;
140		case 19200:
141			return 0x09;
142		case 38400:
143			return 0x0a;
144		case 57600:
145			return 0x0b;
146		case 115200:
147			return 0x0c;
148		default:
149			*result = 9600;
150			return 0x08;
151		}
152	} else {
153		/* FIXME: Can we use any divider - should we do
154		   divider = 115200/value;
155		   real baud = 115200/divider */
156		switch (value) {
157		case 300: break;
158		case 600: break;
159		case 1200: break;
160		case 2400: break;
161		case 4800: break;
162		case 9600: break;
163		case 19200: break;
164		case 38400: break;
165		case 57600: break;
166		case 115200: break;
167		default:
168			value = 9600;
169			*result = 9600;
170		}
171		return 115200/value;
172	}
173}
174
175static int mct_u232_set_baud_rate(struct tty_struct *tty,
176	struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
177{
178	unsigned int divisor;
179	int rc;
180	unsigned char *buf;
181	unsigned char cts_enable_byte = 0;
182	speed_t speed;
183
184	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
185	if (buf == NULL)
186		return -ENOMEM;
187
188	divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
189	put_unaligned_le32(divisor, buf);
190	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
191				MCT_U232_SET_BAUD_RATE_REQUEST,
192				MCT_U232_SET_REQUEST_TYPE,
193				0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
194				WDR_TIMEOUT);
195	if (rc < 0)	/*FIXME: What value speed results */
196		dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
197			value, rc);
198	else
199		tty_encode_baud_rate(tty, speed, speed);
200	dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
201
202	/* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
203	   always sends two extra USB 'device request' messages after the
204	   'baud rate change' message.  The actual functionality of the
205	   request codes in these messages is not fully understood but these
206	   particular codes are never seen in any operation besides a baud
207	   rate change.  Both of these messages send a single byte of data.
208	   In the first message, the value of this byte is always zero.
209
210	   The second message has been determined experimentally to control
211	   whether data will be transmitted to a device which is not asserting
212	   the 'CTS' signal.  If the second message's data byte is zero, data
213	   will be transmitted even if 'CTS' is not asserted (i.e. no hardware
214	   flow control).  if the second message's data byte is nonzero (a
215	   value of 1 is used by this driver), data will not be transmitted to
216	   a device which is not asserting 'CTS'.
217	*/
218
219	buf[0] = 0;
220	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
221				MCT_U232_SET_UNKNOWN1_REQUEST,
222				MCT_U232_SET_REQUEST_TYPE,
223				0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
224				WDR_TIMEOUT);
225	if (rc < 0)
226		dev_err(&port->dev, "Sending USB device request code %d "
227			"failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
228			rc);
229
230	if (port && C_CRTSCTS(tty))
231	   cts_enable_byte = 1;
232
233	dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
234		cts_enable_byte);
235	buf[0] = cts_enable_byte;
236	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
237			MCT_U232_SET_CTS_REQUEST,
238			MCT_U232_SET_REQUEST_TYPE,
239			0, 0, buf, MCT_U232_SET_CTS_SIZE,
240			WDR_TIMEOUT);
241	if (rc < 0)
242		dev_err(&port->dev, "Sending USB device request code %d "
243			"failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
244
245	kfree(buf);
246	return rc;
247} /* mct_u232_set_baud_rate */
248
249static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
250				  unsigned char lcr)
251{
252	int rc;
253	unsigned char *buf;
254
255	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
256	if (buf == NULL)
257		return -ENOMEM;
258
259	buf[0] = lcr;
260	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
261			MCT_U232_SET_LINE_CTRL_REQUEST,
262			MCT_U232_SET_REQUEST_TYPE,
263			0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
264			WDR_TIMEOUT);
265	if (rc < 0)
266		dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
267	dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
 
268	kfree(buf);
269	return rc;
270} /* mct_u232_set_line_ctrl */
271
272static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
273				   unsigned int control_state)
274{
275	int rc;
276	unsigned char mcr;
277	unsigned char *buf;
278
279	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
280	if (buf == NULL)
281		return -ENOMEM;
282
283	mcr = MCT_U232_MCR_NONE;
284	if (control_state & TIOCM_DTR)
285		mcr |= MCT_U232_MCR_DTR;
286	if (control_state & TIOCM_RTS)
287		mcr |= MCT_U232_MCR_RTS;
288
289	buf[0] = mcr;
290	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
291			MCT_U232_SET_MODEM_CTRL_REQUEST,
292			MCT_U232_SET_REQUEST_TYPE,
293			0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
294			WDR_TIMEOUT);
295	kfree(buf);
296
297	dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
298
299	if (rc < 0) {
300		dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
 
301		return rc;
302	}
303	return 0;
304} /* mct_u232_set_modem_ctrl */
305
306static int mct_u232_get_modem_stat(struct usb_serial_port *port,
307				   unsigned char *msr)
308{
309	int rc;
310	unsigned char *buf;
311
312	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
313	if (buf == NULL) {
314		*msr = 0;
315		return -ENOMEM;
316	}
317	rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
318			MCT_U232_GET_MODEM_STAT_REQUEST,
319			MCT_U232_GET_REQUEST_TYPE,
320			0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
321			WDR_TIMEOUT);
322	if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
323		dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
324
325		if (rc >= 0)
326			rc = -EIO;
327
328		*msr = 0;
329	} else {
330		*msr = buf[0];
331	}
332	dev_dbg(&port->dev, "get_modem_stat: 0x%x\n", *msr);
333	kfree(buf);
334	return rc;
335} /* mct_u232_get_modem_stat */
336
337static void mct_u232_msr_to_icount(struct async_icount *icount,
338						unsigned char msr)
339{
340	/* Translate Control Line states */
341	if (msr & MCT_U232_MSR_DDSR)
342		icount->dsr++;
343	if (msr & MCT_U232_MSR_DCTS)
344		icount->cts++;
345	if (msr & MCT_U232_MSR_DRI)
346		icount->rng++;
347	if (msr & MCT_U232_MSR_DCD)
348		icount->dcd++;
349} /* mct_u232_msr_to_icount */
350
351static void mct_u232_msr_to_state(struct usb_serial_port *port,
352				  unsigned int *control_state, unsigned char msr)
353{
354	/* Translate Control Line states */
355	if (msr & MCT_U232_MSR_DSR)
356		*control_state |=  TIOCM_DSR;
357	else
358		*control_state &= ~TIOCM_DSR;
359	if (msr & MCT_U232_MSR_CTS)
360		*control_state |=  TIOCM_CTS;
361	else
362		*control_state &= ~TIOCM_CTS;
363	if (msr & MCT_U232_MSR_RI)
364		*control_state |=  TIOCM_RI;
365	else
366		*control_state &= ~TIOCM_RI;
367	if (msr & MCT_U232_MSR_CD)
368		*control_state |=  TIOCM_CD;
369	else
370		*control_state &= ~TIOCM_CD;
371	dev_dbg(&port->dev, "msr_to_state: msr=0x%x ==> state=0x%x\n", msr, *control_state);
372} /* mct_u232_msr_to_state */
373
374/*
375 * Driver's tty interface functions
376 */
377
378static int mct_u232_port_probe(struct usb_serial_port *port)
379{
380	struct usb_serial *serial = port->serial;
381	struct mct_u232_private *priv;
 
382
383	/* check first to simplify error handling */
384	if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) {
385		dev_err(&port->dev, "expected endpoint missing\n");
386		return -ENODEV;
387	}
388
389	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
390	if (!priv)
391		return -ENOMEM;
392
393	/* Use second interrupt-in endpoint for reading. */
394	priv->read_urb = serial->port[1]->interrupt_in_urb;
395	priv->read_urb->context = port;
396
397	spin_lock_init(&priv->lock);
 
 
398
399	usb_set_serial_port_data(port, priv);
 
 
 
 
 
 
 
 
 
400
401	return 0;
402}
403
404static void mct_u232_port_remove(struct usb_serial_port *port)
 
405{
406	struct mct_u232_private *priv;
 
407
408	priv = usb_get_serial_port_data(port);
409	kfree(priv);
410}
 
 
 
411
412static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
413{
414	struct usb_serial *serial = port->serial;
415	struct mct_u232_private *priv = usb_get_serial_port_data(port);
416	int retval = 0;
417	unsigned int control_state;
418	unsigned long flags;
419	unsigned char last_lcr;
420	unsigned char last_msr;
421
422	/* Compensate for a hardware bug: although the Sitecom U232-P25
423	 * device reports a maximum output packet size of 32 bytes,
424	 * it seems to be able to accept only 16 bytes (and that's what
425	 * SniffUSB says too...)
426	 */
427	if (le16_to_cpu(serial->dev->descriptor.idProduct)
428						== MCT_U232_SITECOM_PID)
429		port->bulk_out_size = 16;
430
431	/* Do a defined restart: the normal serial device seems to
432	 * always turn on DTR and RTS here, so do the same. I'm not
433	 * sure if this is really necessary. But it should not harm
434	 * either.
435	 */
436	spin_lock_irqsave(&priv->lock, flags);
437	if (tty && C_BAUD(tty))
438		priv->control_state = TIOCM_DTR | TIOCM_RTS;
439	else
440		priv->control_state = 0;
441
442	priv->last_lcr = (MCT_U232_DATA_BITS_8 |
443			  MCT_U232_PARITY_NONE |
444			  MCT_U232_STOP_BITS_1);
445	control_state = priv->control_state;
446	last_lcr = priv->last_lcr;
447	spin_unlock_irqrestore(&priv->lock, flags);
448	mct_u232_set_modem_ctrl(port, control_state);
449	mct_u232_set_line_ctrl(port, last_lcr);
450
451	/* Read modem status and update control state */
452	mct_u232_get_modem_stat(port, &last_msr);
453	spin_lock_irqsave(&priv->lock, flags);
454	priv->last_msr = last_msr;
455	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
456	spin_unlock_irqrestore(&priv->lock, flags);
457
458	retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
459	if (retval) {
460		dev_err(&port->dev,
461			"usb_submit_urb(read) failed pipe 0x%x err %d\n",
462			port->read_urb->pipe, retval);
463		goto error;
464	}
465
466	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
467	if (retval) {
468		usb_kill_urb(priv->read_urb);
469		dev_err(&port->dev,
470			"usb_submit_urb(read int) failed pipe 0x%x err %d",
471			port->interrupt_in_urb->pipe, retval);
472		goto error;
473	}
474	return 0;
475
476error:
477	return retval;
478} /* mct_u232_open */
479
480static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
481{
482	unsigned int control_state;
483	struct mct_u232_private *priv = usb_get_serial_port_data(port);
484
485	spin_lock_irq(&priv->lock);
486	if (on)
487		priv->control_state |= TIOCM_DTR | TIOCM_RTS;
488	else
489		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
490	control_state = priv->control_state;
491	spin_unlock_irq(&priv->lock);
492
493	mct_u232_set_modem_ctrl(port, control_state);
 
 
 
 
494}
495
496static void mct_u232_close(struct usb_serial_port *port)
497{
498	struct mct_u232_private *priv = usb_get_serial_port_data(port);
499
500	usb_kill_urb(priv->read_urb);
501	usb_kill_urb(port->interrupt_in_urb);
502
503	usb_serial_generic_close(port);
504} /* mct_u232_close */
505
506
507static void mct_u232_read_int_callback(struct urb *urb)
508{
509	struct usb_serial_port *port = urb->context;
510	struct mct_u232_private *priv = usb_get_serial_port_data(port);
 
 
511	unsigned char *data = urb->transfer_buffer;
512	int retval;
513	int status = urb->status;
514	unsigned long flags;
515
516	switch (status) {
517	case 0:
518		/* success */
519		break;
520	case -ECONNRESET:
521	case -ENOENT:
522	case -ESHUTDOWN:
523		/* this urb is terminated, clean up */
524		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
525			__func__, status);
526		return;
527	default:
528		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
529			__func__, status);
530		goto exit;
531	}
532
533	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 
 
 
 
 
 
534
535	/*
536	 * Work-a-round: handle the 'usual' bulk-in pipe here
537	 */
538	if (urb->transfer_buffer_length > 2) {
539		if (urb->actual_length) {
540			tty_insert_flip_string(&port->port, data,
541					urb->actual_length);
542			tty_flip_buffer_push(&port->port);
 
 
 
 
543		}
544		goto exit;
545	}
546
547	/*
548	 * The interrupt-in pipe signals exceptional conditions (modem line
549	 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
550	 */
551	spin_lock_irqsave(&priv->lock, flags);
552	priv->last_msr = data[MCT_U232_MSR_INDEX];
553
554	/* Record Control Line states */
555	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
556
557	mct_u232_msr_to_icount(&port->icount, priv->last_msr);
558
559#if 0
560	/* Not yet handled. See belkin_sa.c for further information */
561	/* Now to report any errors */
562	priv->last_lsr = data[MCT_U232_LSR_INDEX];
563	/*
564	 * fill in the flip buffer here, but I do not know the relation
565	 * to the current/next receive buffer or characters.  I need
566	 * to look in to this before committing any code.
567	 */
568	if (priv->last_lsr & MCT_U232_LSR_ERR) {
569		tty = tty_port_tty_get(&port->port);
570		/* Overrun Error */
571		if (priv->last_lsr & MCT_U232_LSR_OE) {
572		}
573		/* Parity Error */
574		if (priv->last_lsr & MCT_U232_LSR_PE) {
575		}
576		/* Framing Error */
577		if (priv->last_lsr & MCT_U232_LSR_FE) {
578		}
579		/* Break Indicator */
580		if (priv->last_lsr & MCT_U232_LSR_BI) {
581		}
582		tty_kref_put(tty);
583	}
584#endif
585	wake_up_interruptible(&port->port.delta_msr_wait);
586	spin_unlock_irqrestore(&priv->lock, flags);
587exit:
588	retval = usb_submit_urb(urb, GFP_ATOMIC);
589	if (retval)
590		dev_err(&port->dev,
591			"%s - usb_submit_urb failed with result %d\n",
592			__func__, retval);
593} /* mct_u232_read_int_callback */
594
595static void mct_u232_set_termios(struct tty_struct *tty,
596				 struct usb_serial_port *port,
597				 const struct ktermios *old_termios)
598{
599	struct usb_serial *serial = port->serial;
600	struct mct_u232_private *priv = usb_get_serial_port_data(port);
601	struct ktermios *termios = &tty->termios;
602	unsigned int cflag = termios->c_cflag;
603	unsigned int old_cflag = old_termios->c_cflag;
604	unsigned long flags;
605	unsigned int control_state;
606	unsigned char last_lcr;
607
608	/* get a local copy of the current port settings */
609	spin_lock_irqsave(&priv->lock, flags);
610	control_state = priv->control_state;
611	spin_unlock_irqrestore(&priv->lock, flags);
612	last_lcr = 0;
613
614	/*
615	 * Update baud rate.
616	 * Do not attempt to cache old rates and skip settings,
617	 * disconnects screw such tricks up completely.
618	 * Premature optimization is the root of all evil.
619	 */
620
621	/* reassert DTR and RTS on transition from B0 */
622	if ((old_cflag & CBAUD) == B0) {
623		dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
624		control_state |= TIOCM_DTR | TIOCM_RTS;
625		mct_u232_set_modem_ctrl(port, control_state);
626	}
627
628	mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
629
630	if ((cflag & CBAUD) == B0) {
631		dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
632		/* Drop RTS and DTR */
633		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
634		mct_u232_set_modem_ctrl(port, control_state);
635	}
636
637	/*
638	 * Update line control register (LCR)
639	 */
640
641	/* set the parity */
642	if (cflag & PARENB)
643		last_lcr |= (cflag & PARODD) ?
644			MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
645	else
646		last_lcr |= MCT_U232_PARITY_NONE;
647
648	/* set the number of data bits */
649	switch (cflag & CSIZE) {
650	case CS5:
651		last_lcr |= MCT_U232_DATA_BITS_5; break;
652	case CS6:
653		last_lcr |= MCT_U232_DATA_BITS_6; break;
654	case CS7:
655		last_lcr |= MCT_U232_DATA_BITS_7; break;
656	case CS8:
657		last_lcr |= MCT_U232_DATA_BITS_8; break;
658	default:
659		dev_err(&port->dev,
660			"CSIZE was not CS5-CS8, using default of 8\n");
661		last_lcr |= MCT_U232_DATA_BITS_8;
662		break;
663	}
664
665	termios->c_cflag &= ~CMSPAR;
666
667	/* set the number of stop bits */
668	last_lcr |= (cflag & CSTOPB) ?
669		MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
670
671	mct_u232_set_line_ctrl(port, last_lcr);
672
673	/* save off the modified port settings */
674	spin_lock_irqsave(&priv->lock, flags);
675	priv->control_state = control_state;
676	priv->last_lcr = last_lcr;
677	spin_unlock_irqrestore(&priv->lock, flags);
678} /* mct_u232_set_termios */
679
680static int mct_u232_break_ctl(struct tty_struct *tty, int break_state)
681{
682	struct usb_serial_port *port = tty->driver_data;
 
683	struct mct_u232_private *priv = usb_get_serial_port_data(port);
684	unsigned char lcr;
685	unsigned long flags;
686
687	spin_lock_irqsave(&priv->lock, flags);
688	lcr = priv->last_lcr;
689
690	if (break_state)
691		lcr |= MCT_U232_SET_BREAK;
692	spin_unlock_irqrestore(&priv->lock, flags);
693
694	return mct_u232_set_line_ctrl(port, lcr);
695} /* mct_u232_break_ctl */
696
697
698static int mct_u232_tiocmget(struct tty_struct *tty)
699{
700	struct usb_serial_port *port = tty->driver_data;
701	struct mct_u232_private *priv = usb_get_serial_port_data(port);
702	unsigned int control_state;
703	unsigned long flags;
704
705	spin_lock_irqsave(&priv->lock, flags);
706	control_state = priv->control_state;
707	spin_unlock_irqrestore(&priv->lock, flags);
708
709	return control_state;
710}
711
712static int mct_u232_tiocmset(struct tty_struct *tty,
713			      unsigned int set, unsigned int clear)
714{
715	struct usb_serial_port *port = tty->driver_data;
 
716	struct mct_u232_private *priv = usb_get_serial_port_data(port);
717	unsigned int control_state;
718	unsigned long flags;
719
720	spin_lock_irqsave(&priv->lock, flags);
721	control_state = priv->control_state;
722
723	if (set & TIOCM_RTS)
724		control_state |= TIOCM_RTS;
725	if (set & TIOCM_DTR)
726		control_state |= TIOCM_DTR;
727	if (clear & TIOCM_RTS)
728		control_state &= ~TIOCM_RTS;
729	if (clear & TIOCM_DTR)
730		control_state &= ~TIOCM_DTR;
731
732	priv->control_state = control_state;
733	spin_unlock_irqrestore(&priv->lock, flags);
734	return mct_u232_set_modem_ctrl(port, control_state);
735}
736
737static void mct_u232_throttle(struct tty_struct *tty)
738{
739	struct usb_serial_port *port = tty->driver_data;
740	struct mct_u232_private *priv = usb_get_serial_port_data(port);
741	unsigned int control_state;
742
743	spin_lock_irq(&priv->lock);
744	priv->rx_flags |= THROTTLED;
745	if (C_CRTSCTS(tty)) {
746		priv->control_state &= ~TIOCM_RTS;
747		control_state = priv->control_state;
748		spin_unlock_irq(&priv->lock);
749		mct_u232_set_modem_ctrl(port, control_state);
750	} else {
751		spin_unlock_irq(&priv->lock);
752	}
753}
754
755static void mct_u232_unthrottle(struct tty_struct *tty)
756{
757	struct usb_serial_port *port = tty->driver_data;
758	struct mct_u232_private *priv = usb_get_serial_port_data(port);
759	unsigned int control_state;
760
761	spin_lock_irq(&priv->lock);
762	if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
763		priv->rx_flags &= ~THROTTLED;
764		priv->control_state |= TIOCM_RTS;
765		control_state = priv->control_state;
766		spin_unlock_irq(&priv->lock);
767		mct_u232_set_modem_ctrl(port, control_state);
768	} else {
769		spin_unlock_irq(&priv->lock);
770	}
771}
772
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
773module_usb_serial_driver(serial_drivers, id_table);
774
775MODULE_AUTHOR(DRIVER_AUTHOR);
776MODULE_DESCRIPTION(DRIVER_DESC);
777MODULE_LICENSE("GPL");
v3.5.6
 
  1/*
  2 * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
  3 *
  4 *   Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
  5 *
  6 *   This program is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU General Public License as published by
  8 *   the Free Software Foundation; either version 2 of the License, or
  9 *   (at your option) any later version.
 10 *
 11 * This program is largely derived from the Belkin USB Serial Adapter Driver
 12 * (see belkin_sa.[ch]). All of the information about the device was acquired
 13 * by using SniffUSB on Windows98. For technical details see mct_u232.h.
 14 *
 15 * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
 16 * do the reverse engineering and how to write a USB serial device driver.
 17 *
 18 * TO BE DONE, TO BE CHECKED:
 19 *   DTR/RTS signal handling may be incomplete or incorrect. I have mainly
 20 *   implemented what I have seen with SniffUSB or found in belkin_sa.c.
 21 *   For further TODOs check also belkin_sa.c.
 22 */
 23
 24#include <linux/kernel.h>
 25#include <linux/errno.h>
 26#include <linux/init.h>
 27#include <linux/slab.h>
 28#include <linux/tty.h>
 29#include <linux/tty_driver.h>
 30#include <linux/tty_flip.h>
 31#include <linux/module.h>
 32#include <linux/spinlock.h>
 33#include <linux/uaccess.h>
 34#include <asm/unaligned.h>
 35#include <linux/usb.h>
 36#include <linux/usb/serial.h>
 37#include <linux/serial.h>
 38#include <linux/ioctl.h>
 39#include "mct_u232.h"
 40
 41/*
 42 * Version Information
 43 */
 44#define DRIVER_VERSION "z2.1"		/* Linux in-kernel version */
 45#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
 46#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
 47
 48static bool debug;
 49
 50/*
 51 * Function prototypes
 52 */
 53static int  mct_u232_startup(struct usb_serial *serial);
 54static void mct_u232_release(struct usb_serial *serial);
 55static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
 56static void mct_u232_close(struct usb_serial_port *port);
 57static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
 58static void mct_u232_read_int_callback(struct urb *urb);
 59static void mct_u232_set_termios(struct tty_struct *tty,
 60			struct usb_serial_port *port, struct ktermios *old);
 61static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
 
 62static int  mct_u232_tiocmget(struct tty_struct *tty);
 63static int  mct_u232_tiocmset(struct tty_struct *tty,
 64			unsigned int set, unsigned int clear);
 65static int  mct_u232_ioctl(struct tty_struct *tty,
 66			unsigned int cmd, unsigned long arg);
 67static int  mct_u232_get_icount(struct tty_struct *tty,
 68			struct serial_icounter_struct *icount);
 69static void mct_u232_throttle(struct tty_struct *tty);
 70static void mct_u232_unthrottle(struct tty_struct *tty);
 71
 72
 73/*
 74 * All of the device info needed for the MCT USB-RS232 converter.
 75 */
 76static const struct usb_device_id id_table[] = {
 77	{ USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
 78	{ USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
 79	{ USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
 80	{ USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
 81	{ }		/* Terminating entry */
 82};
 83MODULE_DEVICE_TABLE(usb, id_table);
 84
 85static struct usb_serial_driver mct_u232_device = {
 86	.driver = {
 87		.owner =	THIS_MODULE,
 88		.name =		"mct_u232",
 89	},
 90	.description =	     "MCT U232",
 91	.id_table =	     id_table,
 92	.num_ports =	     1,
 93	.open =		     mct_u232_open,
 94	.close =	     mct_u232_close,
 95	.dtr_rts =	     mct_u232_dtr_rts,
 96	.throttle =	     mct_u232_throttle,
 97	.unthrottle =	     mct_u232_unthrottle,
 98	.read_int_callback = mct_u232_read_int_callback,
 99	.set_termios =	     mct_u232_set_termios,
100	.break_ctl =	     mct_u232_break_ctl,
101	.tiocmget =	     mct_u232_tiocmget,
102	.tiocmset =	     mct_u232_tiocmset,
103	.attach =	     mct_u232_startup,
104	.release =	     mct_u232_release,
105	.ioctl =             mct_u232_ioctl,
106	.get_icount =        mct_u232_get_icount,
107};
108
109static struct usb_serial_driver * const serial_drivers[] = {
110	&mct_u232_device, NULL
111};
112
113struct mct_u232_private {
 
114	spinlock_t lock;
115	unsigned int	     control_state; /* Modem Line Setting (TIOCM) */
116	unsigned char        last_lcr;      /* Line Control Register */
117	unsigned char	     last_lsr;      /* Line Status Register */
118	unsigned char	     last_msr;      /* Modem Status Register */
119	unsigned int	     rx_flags;      /* Throttling flags */
120	struct async_icount  icount;
121	wait_queue_head_t    msr_wait;	/* for handling sleeping while waiting
122						for msr change to happen */
123};
124
125#define THROTTLED		0x01
126
127/*
128 * Handle vendor specific USB requests
129 */
130
131#define WDR_TIMEOUT 5000 /* default urb timeout */
132
133/*
134 * Later day 2.6.0-test kernels have new baud rates like B230400 which
135 * we do not know how to support. We ignore them for the moment.
136 */
137static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
138					speed_t value, speed_t *result)
139{
140	*result = value;
141
142	if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
143		|| le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
144		switch (value) {
145		case 300:
146			return 0x01;
147		case 600:
148			return 0x02; /* this one not tested */
149		case 1200:
150			return 0x03;
151		case 2400:
152			return 0x04;
153		case 4800:
154			return 0x06;
155		case 9600:
156			return 0x08;
157		case 19200:
158			return 0x09;
159		case 38400:
160			return 0x0a;
161		case 57600:
162			return 0x0b;
163		case 115200:
164			return 0x0c;
165		default:
166			*result = 9600;
167			return 0x08;
168		}
169	} else {
170		/* FIXME: Can we use any divider - should we do
171		   divider = 115200/value;
172		   real baud = 115200/divider */
173		switch (value) {
174		case 300: break;
175		case 600: break;
176		case 1200: break;
177		case 2400: break;
178		case 4800: break;
179		case 9600: break;
180		case 19200: break;
181		case 38400: break;
182		case 57600: break;
183		case 115200: break;
184		default:
185			value = 9600;
186			*result = 9600;
187		}
188		return 115200/value;
189	}
190}
191
192static int mct_u232_set_baud_rate(struct tty_struct *tty,
193	struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
194{
195	unsigned int divisor;
196	int rc;
197	unsigned char *buf;
198	unsigned char cts_enable_byte = 0;
199	speed_t speed;
200
201	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
202	if (buf == NULL)
203		return -ENOMEM;
204
205	divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
206	put_unaligned_le32(cpu_to_le32(divisor), buf);
207	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
208				MCT_U232_SET_BAUD_RATE_REQUEST,
209				MCT_U232_SET_REQUEST_TYPE,
210				0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
211				WDR_TIMEOUT);
212	if (rc < 0)	/*FIXME: What value speed results */
213		dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
214			value, rc);
215	else
216		tty_encode_baud_rate(tty, speed, speed);
217	dbg("set_baud_rate: value: 0x%x, divisor: 0x%x", value, divisor);
218
219	/* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
220	   always sends two extra USB 'device request' messages after the
221	   'baud rate change' message.  The actual functionality of the
222	   request codes in these messages is not fully understood but these
223	   particular codes are never seen in any operation besides a baud
224	   rate change.  Both of these messages send a single byte of data.
225	   In the first message, the value of this byte is always zero.
226
227	   The second message has been determined experimentally to control
228	   whether data will be transmitted to a device which is not asserting
229	   the 'CTS' signal.  If the second message's data byte is zero, data
230	   will be transmitted even if 'CTS' is not asserted (i.e. no hardware
231	   flow control).  if the second message's data byte is nonzero (a
232	   value of 1 is used by this driver), data will not be transmitted to
233	   a device which is not asserting 'CTS'.
234	*/
235
236	buf[0] = 0;
237	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
238				MCT_U232_SET_UNKNOWN1_REQUEST,
239				MCT_U232_SET_REQUEST_TYPE,
240				0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
241				WDR_TIMEOUT);
242	if (rc < 0)
243		dev_err(&port->dev, "Sending USB device request code %d "
244			"failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
245			rc);
246
247	if (port && C_CRTSCTS(tty))
248	   cts_enable_byte = 1;
249
250	dbg("set_baud_rate: send second control message, data = %02X",
251							cts_enable_byte);
252	buf[0] = cts_enable_byte;
253	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
254			MCT_U232_SET_CTS_REQUEST,
255			MCT_U232_SET_REQUEST_TYPE,
256			0, 0, buf, MCT_U232_SET_CTS_SIZE,
257			WDR_TIMEOUT);
258	if (rc < 0)
259		dev_err(&port->dev, "Sending USB device request code %d "
260			"failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
261
262	kfree(buf);
263	return rc;
264} /* mct_u232_set_baud_rate */
265
266static int mct_u232_set_line_ctrl(struct usb_serial *serial, unsigned char lcr)
 
267{
268	int rc;
269	unsigned char *buf;
270
271	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
272	if (buf == NULL)
273		return -ENOMEM;
274
275	buf[0] = lcr;
276	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
277			MCT_U232_SET_LINE_CTRL_REQUEST,
278			MCT_U232_SET_REQUEST_TYPE,
279			0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
280			WDR_TIMEOUT);
281	if (rc < 0)
282		dev_err(&serial->dev->dev,
283			"Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
284	dbg("set_line_ctrl: 0x%x", lcr);
285	kfree(buf);
286	return rc;
287} /* mct_u232_set_line_ctrl */
288
289static int mct_u232_set_modem_ctrl(struct usb_serial *serial,
290				   unsigned int control_state)
291{
292	int rc;
293	unsigned char mcr;
294	unsigned char *buf;
295
296	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
297	if (buf == NULL)
298		return -ENOMEM;
299
300	mcr = MCT_U232_MCR_NONE;
301	if (control_state & TIOCM_DTR)
302		mcr |= MCT_U232_MCR_DTR;
303	if (control_state & TIOCM_RTS)
304		mcr |= MCT_U232_MCR_RTS;
305
306	buf[0] = mcr;
307	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
308			MCT_U232_SET_MODEM_CTRL_REQUEST,
309			MCT_U232_SET_REQUEST_TYPE,
310			0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
311			WDR_TIMEOUT);
312	kfree(buf);
313
314	dbg("set_modem_ctrl: state=0x%x ==> mcr=0x%x", control_state, mcr);
315
316	if (rc < 0) {
317		dev_err(&serial->dev->dev,
318			"Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
319		return rc;
320	}
321	return 0;
322} /* mct_u232_set_modem_ctrl */
323
324static int mct_u232_get_modem_stat(struct usb_serial *serial,
325						unsigned char *msr)
326{
327	int rc;
328	unsigned char *buf;
329
330	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
331	if (buf == NULL) {
332		*msr = 0;
333		return -ENOMEM;
334	}
335	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
336			MCT_U232_GET_MODEM_STAT_REQUEST,
337			MCT_U232_GET_REQUEST_TYPE,
338			0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
339			WDR_TIMEOUT);
340	if (rc < 0) {
341		dev_err(&serial->dev->dev,
342			"Get MODEM STATus failed (error = %d)\n", rc);
 
 
 
343		*msr = 0;
344	} else {
345		*msr = buf[0];
346	}
347	dbg("get_modem_stat: 0x%x", *msr);
348	kfree(buf);
349	return rc;
350} /* mct_u232_get_modem_stat */
351
352static void mct_u232_msr_to_icount(struct async_icount *icount,
353						unsigned char msr)
354{
355	/* Translate Control Line states */
356	if (msr & MCT_U232_MSR_DDSR)
357		icount->dsr++;
358	if (msr & MCT_U232_MSR_DCTS)
359		icount->cts++;
360	if (msr & MCT_U232_MSR_DRI)
361		icount->rng++;
362	if (msr & MCT_U232_MSR_DCD)
363		icount->dcd++;
364} /* mct_u232_msr_to_icount */
365
366static void mct_u232_msr_to_state(unsigned int *control_state,
367						unsigned char msr)
368{
369	/* Translate Control Line states */
370	if (msr & MCT_U232_MSR_DSR)
371		*control_state |=  TIOCM_DSR;
372	else
373		*control_state &= ~TIOCM_DSR;
374	if (msr & MCT_U232_MSR_CTS)
375		*control_state |=  TIOCM_CTS;
376	else
377		*control_state &= ~TIOCM_CTS;
378	if (msr & MCT_U232_MSR_RI)
379		*control_state |=  TIOCM_RI;
380	else
381		*control_state &= ~TIOCM_RI;
382	if (msr & MCT_U232_MSR_CD)
383		*control_state |=  TIOCM_CD;
384	else
385		*control_state &= ~TIOCM_CD;
386	dbg("msr_to_state: msr=0x%x ==> state=0x%x", msr, *control_state);
387} /* mct_u232_msr_to_state */
388
389/*
390 * Driver's tty interface functions
391 */
392
393static int mct_u232_startup(struct usb_serial *serial)
394{
 
395	struct mct_u232_private *priv;
396	struct usb_serial_port *port, *rport;
397
398	priv = kzalloc(sizeof(struct mct_u232_private), GFP_KERNEL);
 
 
 
 
 
 
399	if (!priv)
400		return -ENOMEM;
 
 
 
 
 
401	spin_lock_init(&priv->lock);
402	init_waitqueue_head(&priv->msr_wait);
403	usb_set_serial_port_data(serial->port[0], priv);
404
405	init_waitqueue_head(&serial->port[0]->write_wait);
406
407	/* Puh, that's dirty */
408	port = serial->port[0];
409	rport = serial->port[1];
410	/* No unlinking, it wasn't submitted yet. */
411	usb_free_urb(port->read_urb);
412	port->read_urb = rport->interrupt_in_urb;
413	rport->interrupt_in_urb = NULL;
414	port->read_urb->context = port;
415
416	return 0;
417} /* mct_u232_startup */
418
419
420static void mct_u232_release(struct usb_serial *serial)
421{
422	struct mct_u232_private *priv;
423	int i;
424
425	for (i = 0; i < serial->num_ports; ++i) {
426		/* My special items, the standard routines free my urbs */
427		priv = usb_get_serial_port_data(serial->port[i]);
428		kfree(priv);
429	}
430} /* mct_u232_release */
431
432static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
433{
434	struct usb_serial *serial = port->serial;
435	struct mct_u232_private *priv = usb_get_serial_port_data(port);
436	int retval = 0;
437	unsigned int control_state;
438	unsigned long flags;
439	unsigned char last_lcr;
440	unsigned char last_msr;
441
442	/* Compensate for a hardware bug: although the Sitecom U232-P25
443	 * device reports a maximum output packet size of 32 bytes,
444	 * it seems to be able to accept only 16 bytes (and that's what
445	 * SniffUSB says too...)
446	 */
447	if (le16_to_cpu(serial->dev->descriptor.idProduct)
448						== MCT_U232_SITECOM_PID)
449		port->bulk_out_size = 16;
450
451	/* Do a defined restart: the normal serial device seems to
452	 * always turn on DTR and RTS here, so do the same. I'm not
453	 * sure if this is really necessary. But it should not harm
454	 * either.
455	 */
456	spin_lock_irqsave(&priv->lock, flags);
457	if (tty && (tty->termios->c_cflag & CBAUD))
458		priv->control_state = TIOCM_DTR | TIOCM_RTS;
459	else
460		priv->control_state = 0;
461
462	priv->last_lcr = (MCT_U232_DATA_BITS_8 |
463			  MCT_U232_PARITY_NONE |
464			  MCT_U232_STOP_BITS_1);
465	control_state = priv->control_state;
466	last_lcr = priv->last_lcr;
467	spin_unlock_irqrestore(&priv->lock, flags);
468	mct_u232_set_modem_ctrl(serial, control_state);
469	mct_u232_set_line_ctrl(serial, last_lcr);
470
471	/* Read modem status and update control state */
472	mct_u232_get_modem_stat(serial, &last_msr);
473	spin_lock_irqsave(&priv->lock, flags);
474	priv->last_msr = last_msr;
475	mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
476	spin_unlock_irqrestore(&priv->lock, flags);
477
478	retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
479	if (retval) {
480		dev_err(&port->dev,
481			"usb_submit_urb(read bulk) failed pipe 0x%x err %d\n",
482			port->read_urb->pipe, retval);
483		goto error;
484	}
485
486	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
487	if (retval) {
488		usb_kill_urb(port->read_urb);
489		dev_err(&port->dev,
490			"usb_submit_urb(read int) failed pipe 0x%x err %d",
491			port->interrupt_in_urb->pipe, retval);
492		goto error;
493	}
494	return 0;
495
496error:
497	return retval;
498} /* mct_u232_open */
499
500static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
501{
502	unsigned int control_state;
503	struct mct_u232_private *priv = usb_get_serial_port_data(port);
504
505	mutex_lock(&port->serial->disc_mutex);
506	if (!port->serial->disconnected) {
507		/* drop DTR and RTS */
508		spin_lock_irq(&priv->lock);
509		if (on)
510			priv->control_state |= TIOCM_DTR | TIOCM_RTS;
511		else
512			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
513		control_state = priv->control_state;
514		spin_unlock_irq(&priv->lock);
515		mct_u232_set_modem_ctrl(port->serial, control_state);
516	}
517	mutex_unlock(&port->serial->disc_mutex);
518}
519
520static void mct_u232_close(struct usb_serial_port *port)
521{
522	if (port->serial->dev) {
523		/* shutdown our urbs */
524		usb_kill_urb(port->write_urb);
525		usb_kill_urb(port->read_urb);
526		usb_kill_urb(port->interrupt_in_urb);
527	}
528} /* mct_u232_close */
529
530
531static void mct_u232_read_int_callback(struct urb *urb)
532{
533	struct usb_serial_port *port = urb->context;
534	struct mct_u232_private *priv = usb_get_serial_port_data(port);
535	struct usb_serial *serial = port->serial;
536	struct tty_struct *tty;
537	unsigned char *data = urb->transfer_buffer;
538	int retval;
539	int status = urb->status;
540	unsigned long flags;
541
542	switch (status) {
543	case 0:
544		/* success */
545		break;
546	case -ECONNRESET:
547	case -ENOENT:
548	case -ESHUTDOWN:
549		/* this urb is terminated, clean up */
550		dbg("%s - urb shutting down with status: %d",
551		    __func__, status);
552		return;
553	default:
554		dbg("%s - nonzero urb status received: %d",
555		    __func__, status);
556		goto exit;
557	}
558
559	if (!serial) {
560		dbg("%s - bad serial pointer, exiting", __func__);
561		return;
562	}
563
564	usb_serial_debug_data(debug, &port->dev, __func__,
565					urb->actual_length, data);
566
567	/*
568	 * Work-a-round: handle the 'usual' bulk-in pipe here
569	 */
570	if (urb->transfer_buffer_length > 2) {
571		if (urb->actual_length) {
572			tty = tty_port_tty_get(&port->port);
573			if (tty) {
574				tty_insert_flip_string(tty, data,
575						urb->actual_length);
576				tty_flip_buffer_push(tty);
577			}
578			tty_kref_put(tty);
579		}
580		goto exit;
581	}
582
583	/*
584	 * The interrupt-in pipe signals exceptional conditions (modem line
585	 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
586	 */
587	spin_lock_irqsave(&priv->lock, flags);
588	priv->last_msr = data[MCT_U232_MSR_INDEX];
589
590	/* Record Control Line states */
591	mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
592
593	mct_u232_msr_to_icount(&priv->icount, priv->last_msr);
594
595#if 0
596	/* Not yet handled. See belkin_sa.c for further information */
597	/* Now to report any errors */
598	priv->last_lsr = data[MCT_U232_LSR_INDEX];
599	/*
600	 * fill in the flip buffer here, but I do not know the relation
601	 * to the current/next receive buffer or characters.  I need
602	 * to look in to this before committing any code.
603	 */
604	if (priv->last_lsr & MCT_U232_LSR_ERR) {
605		tty = tty_port_tty_get(&port->port);
606		/* Overrun Error */
607		if (priv->last_lsr & MCT_U232_LSR_OE) {
608		}
609		/* Parity Error */
610		if (priv->last_lsr & MCT_U232_LSR_PE) {
611		}
612		/* Framing Error */
613		if (priv->last_lsr & MCT_U232_LSR_FE) {
614		}
615		/* Break Indicator */
616		if (priv->last_lsr & MCT_U232_LSR_BI) {
617		}
618		tty_kref_put(tty);
619	}
620#endif
621	wake_up_interruptible(&priv->msr_wait);
622	spin_unlock_irqrestore(&priv->lock, flags);
623exit:
624	retval = usb_submit_urb(urb, GFP_ATOMIC);
625	if (retval)
626		dev_err(&port->dev,
627			"%s - usb_submit_urb failed with result %d\n",
628			__func__, retval);
629} /* mct_u232_read_int_callback */
630
631static void mct_u232_set_termios(struct tty_struct *tty,
632				 struct usb_serial_port *port,
633				 struct ktermios *old_termios)
634{
635	struct usb_serial *serial = port->serial;
636	struct mct_u232_private *priv = usb_get_serial_port_data(port);
637	struct ktermios *termios = tty->termios;
638	unsigned int cflag = termios->c_cflag;
639	unsigned int old_cflag = old_termios->c_cflag;
640	unsigned long flags;
641	unsigned int control_state;
642	unsigned char last_lcr;
643
644	/* get a local copy of the current port settings */
645	spin_lock_irqsave(&priv->lock, flags);
646	control_state = priv->control_state;
647	spin_unlock_irqrestore(&priv->lock, flags);
648	last_lcr = 0;
649
650	/*
651	 * Update baud rate.
652	 * Do not attempt to cache old rates and skip settings,
653	 * disconnects screw such tricks up completely.
654	 * Premature optimization is the root of all evil.
655	 */
656
657	/* reassert DTR and RTS on transition from B0 */
658	if ((old_cflag & CBAUD) == B0) {
659		dbg("%s: baud was B0", __func__);
660		control_state |= TIOCM_DTR | TIOCM_RTS;
661		mct_u232_set_modem_ctrl(serial, control_state);
662	}
663
664	mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
665
666	if ((cflag & CBAUD) == B0) {
667		dbg("%s: baud is B0", __func__);
668		/* Drop RTS and DTR */
669		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
670		mct_u232_set_modem_ctrl(serial, control_state);
671	}
672
673	/*
674	 * Update line control register (LCR)
675	 */
676
677	/* set the parity */
678	if (cflag & PARENB)
679		last_lcr |= (cflag & PARODD) ?
680			MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
681	else
682		last_lcr |= MCT_U232_PARITY_NONE;
683
684	/* set the number of data bits */
685	switch (cflag & CSIZE) {
686	case CS5:
687		last_lcr |= MCT_U232_DATA_BITS_5; break;
688	case CS6:
689		last_lcr |= MCT_U232_DATA_BITS_6; break;
690	case CS7:
691		last_lcr |= MCT_U232_DATA_BITS_7; break;
692	case CS8:
693		last_lcr |= MCT_U232_DATA_BITS_8; break;
694	default:
695		dev_err(&port->dev,
696			"CSIZE was not CS5-CS8, using default of 8\n");
697		last_lcr |= MCT_U232_DATA_BITS_8;
698		break;
699	}
700
701	termios->c_cflag &= ~CMSPAR;
702
703	/* set the number of stop bits */
704	last_lcr |= (cflag & CSTOPB) ?
705		MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
706
707	mct_u232_set_line_ctrl(serial, last_lcr);
708
709	/* save off the modified port settings */
710	spin_lock_irqsave(&priv->lock, flags);
711	priv->control_state = control_state;
712	priv->last_lcr = last_lcr;
713	spin_unlock_irqrestore(&priv->lock, flags);
714} /* mct_u232_set_termios */
715
716static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
717{
718	struct usb_serial_port *port = tty->driver_data;
719	struct usb_serial *serial = port->serial;
720	struct mct_u232_private *priv = usb_get_serial_port_data(port);
721	unsigned char lcr;
722	unsigned long flags;
723
724	spin_lock_irqsave(&priv->lock, flags);
725	lcr = priv->last_lcr;
726
727	if (break_state)
728		lcr |= MCT_U232_SET_BREAK;
729	spin_unlock_irqrestore(&priv->lock, flags);
730
731	mct_u232_set_line_ctrl(serial, lcr);
732} /* mct_u232_break_ctl */
733
734
735static int mct_u232_tiocmget(struct tty_struct *tty)
736{
737	struct usb_serial_port *port = tty->driver_data;
738	struct mct_u232_private *priv = usb_get_serial_port_data(port);
739	unsigned int control_state;
740	unsigned long flags;
741
742	spin_lock_irqsave(&priv->lock, flags);
743	control_state = priv->control_state;
744	spin_unlock_irqrestore(&priv->lock, flags);
745
746	return control_state;
747}
748
749static int mct_u232_tiocmset(struct tty_struct *tty,
750			      unsigned int set, unsigned int clear)
751{
752	struct usb_serial_port *port = tty->driver_data;
753	struct usb_serial *serial = port->serial;
754	struct mct_u232_private *priv = usb_get_serial_port_data(port);
755	unsigned int control_state;
756	unsigned long flags;
757
758	spin_lock_irqsave(&priv->lock, flags);
759	control_state = priv->control_state;
760
761	if (set & TIOCM_RTS)
762		control_state |= TIOCM_RTS;
763	if (set & TIOCM_DTR)
764		control_state |= TIOCM_DTR;
765	if (clear & TIOCM_RTS)
766		control_state &= ~TIOCM_RTS;
767	if (clear & TIOCM_DTR)
768		control_state &= ~TIOCM_DTR;
769
770	priv->control_state = control_state;
771	spin_unlock_irqrestore(&priv->lock, flags);
772	return mct_u232_set_modem_ctrl(serial, control_state);
773}
774
775static void mct_u232_throttle(struct tty_struct *tty)
776{
777	struct usb_serial_port *port = tty->driver_data;
778	struct mct_u232_private *priv = usb_get_serial_port_data(port);
779	unsigned int control_state;
780
781	spin_lock_irq(&priv->lock);
782	priv->rx_flags |= THROTTLED;
783	if (C_CRTSCTS(tty)) {
784		priv->control_state &= ~TIOCM_RTS;
785		control_state = priv->control_state;
786		spin_unlock_irq(&priv->lock);
787		(void) mct_u232_set_modem_ctrl(port->serial, control_state);
788	} else {
789		spin_unlock_irq(&priv->lock);
790	}
791}
792
793static void mct_u232_unthrottle(struct tty_struct *tty)
794{
795	struct usb_serial_port *port = tty->driver_data;
796	struct mct_u232_private *priv = usb_get_serial_port_data(port);
797	unsigned int control_state;
798
799	spin_lock_irq(&priv->lock);
800	if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
801		priv->rx_flags &= ~THROTTLED;
802		priv->control_state |= TIOCM_RTS;
803		control_state = priv->control_state;
804		spin_unlock_irq(&priv->lock);
805		(void) mct_u232_set_modem_ctrl(port->serial, control_state);
806	} else {
807		spin_unlock_irq(&priv->lock);
808	}
809}
810
811static int  mct_u232_ioctl(struct tty_struct *tty,
812			unsigned int cmd, unsigned long arg)
813{
814	DEFINE_WAIT(wait);
815	struct usb_serial_port *port = tty->driver_data;
816	struct mct_u232_private *mct_u232_port = usb_get_serial_port_data(port);
817	struct async_icount cnow, cprev;
818	unsigned long flags;
819
820	dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
821
822	switch (cmd) {
823
824	case TIOCMIWAIT:
825
826		dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
827
828		spin_lock_irqsave(&mct_u232_port->lock, flags);
829		cprev = mct_u232_port->icount;
830		spin_unlock_irqrestore(&mct_u232_port->lock, flags);
831		for ( ; ; ) {
832			prepare_to_wait(&mct_u232_port->msr_wait,
833					&wait, TASK_INTERRUPTIBLE);
834			schedule();
835			finish_wait(&mct_u232_port->msr_wait, &wait);
836			/* see if a signal did it */
837			if (signal_pending(current))
838				return -ERESTARTSYS;
839			spin_lock_irqsave(&mct_u232_port->lock, flags);
840			cnow = mct_u232_port->icount;
841			spin_unlock_irqrestore(&mct_u232_port->lock, flags);
842			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
843			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
844				return -EIO; /* no change => error */
845			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
846			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
847			    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
848			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
849				return 0;
850			}
851			cprev = cnow;
852		}
853
854	}
855	return -ENOIOCTLCMD;
856}
857
858static int  mct_u232_get_icount(struct tty_struct *tty,
859			struct serial_icounter_struct *icount)
860{
861	struct usb_serial_port *port = tty->driver_data;
862	struct mct_u232_private *mct_u232_port = usb_get_serial_port_data(port);
863	struct async_icount *ic = &mct_u232_port->icount;
864	unsigned long flags;
865
866	spin_lock_irqsave(&mct_u232_port->lock, flags);
867
868	icount->cts = ic->cts;
869	icount->dsr = ic->dsr;
870	icount->rng = ic->rng;
871	icount->dcd = ic->dcd;
872	icount->rx = ic->rx;
873	icount->tx = ic->tx;
874	icount->frame = ic->frame;
875	icount->overrun = ic->overrun;
876	icount->parity = ic->parity;
877	icount->brk = ic->brk;
878	icount->buf_overrun = ic->buf_overrun;
879
880	spin_unlock_irqrestore(&mct_u232_port->lock, flags);
881
882	dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d",
883		__func__,  port->number, icount->rx, icount->tx);
884	return 0;
885}
886
887module_usb_serial_driver(serial_drivers, id_table);
888
889MODULE_AUTHOR(DRIVER_AUTHOR);
890MODULE_DESCRIPTION(DRIVER_DESC);
891MODULE_LICENSE("GPL");
892
893module_param(debug, bool, S_IRUGO | S_IWUSR);
894MODULE_PARM_DESC(debug, "Debug enabled or not");