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v5.9
  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 int  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, struct ktermios *old);
 49static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
 50static int  mct_u232_tiocmget(struct tty_struct *tty);
 51static int  mct_u232_tiocmset(struct tty_struct *tty,
 52			unsigned int set, unsigned int clear);
 
 
 
 
 53static void mct_u232_throttle(struct tty_struct *tty);
 54static void mct_u232_unthrottle(struct tty_struct *tty);
 55
 56
 57/*
 58 * All of the device info needed for the MCT USB-RS232 converter.
 59 */
 60static const struct usb_device_id id_table[] = {
 61	{ USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
 62	{ USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
 63	{ USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
 64	{ USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
 65	{ }		/* Terminating entry */
 66};
 67MODULE_DEVICE_TABLE(usb, id_table);
 68
 69static struct usb_serial_driver mct_u232_device = {
 70	.driver = {
 71		.owner =	THIS_MODULE,
 72		.name =		"mct_u232",
 73	},
 74	.description =	     "MCT U232",
 75	.id_table =	     id_table,
 76	.num_ports =	     1,
 77	.open =		     mct_u232_open,
 78	.close =	     mct_u232_close,
 79	.dtr_rts =	     mct_u232_dtr_rts,
 80	.throttle =	     mct_u232_throttle,
 81	.unthrottle =	     mct_u232_unthrottle,
 82	.read_int_callback = mct_u232_read_int_callback,
 83	.set_termios =	     mct_u232_set_termios,
 84	.break_ctl =	     mct_u232_break_ctl,
 85	.tiocmget =	     mct_u232_tiocmget,
 86	.tiocmset =	     mct_u232_tiocmset,
 87	.tiocmiwait =        usb_serial_generic_tiocmiwait,
 88	.port_probe =        mct_u232_port_probe,
 89	.port_remove =       mct_u232_port_remove,
 90	.get_icount =        usb_serial_generic_get_icount,
 91};
 92
 93static struct usb_serial_driver * const serial_drivers[] = {
 94	&mct_u232_device, NULL
 95};
 96
 97struct mct_u232_private {
 98	struct urb *read_urb;
 99	spinlock_t lock;
100	unsigned int	     control_state; /* Modem Line Setting (TIOCM) */
101	unsigned char        last_lcr;      /* Line Control Register */
102	unsigned char	     last_lsr;      /* Line Status Register */
103	unsigned char	     last_msr;      /* Modem Status Register */
104	unsigned int	     rx_flags;      /* Throttling flags */
 
 
 
105};
106
107#define THROTTLED		0x01
108
109/*
110 * Handle vendor specific USB requests
111 */
112
113#define WDR_TIMEOUT 5000 /* default urb timeout */
114
115/*
116 * Later day 2.6.0-test kernels have new baud rates like B230400 which
117 * we do not know how to support. We ignore them for the moment.
118 */
119static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
120					speed_t value, speed_t *result)
121{
122	*result = value;
123
124	if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
125		|| le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
126		switch (value) {
127		case 300:
128			return 0x01;
129		case 600:
130			return 0x02; /* this one not tested */
131		case 1200:
132			return 0x03;
133		case 2400:
134			return 0x04;
135		case 4800:
136			return 0x06;
137		case 9600:
138			return 0x08;
139		case 19200:
140			return 0x09;
141		case 38400:
142			return 0x0a;
143		case 57600:
144			return 0x0b;
145		case 115200:
146			return 0x0c;
147		default:
148			*result = 9600;
149			return 0x08;
150		}
151	} else {
152		/* FIXME: Can we use any divider - should we do
153		   divider = 115200/value;
154		   real baud = 115200/divider */
155		switch (value) {
156		case 300: break;
157		case 600: break;
158		case 1200: break;
159		case 2400: break;
160		case 4800: break;
161		case 9600: break;
162		case 19200: break;
163		case 38400: break;
164		case 57600: break;
165		case 115200: break;
166		default:
167			value = 9600;
168			*result = 9600;
169		}
170		return 115200/value;
171	}
172}
173
174static int mct_u232_set_baud_rate(struct tty_struct *tty,
175	struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
176{
177	unsigned int divisor;
178	int rc;
179	unsigned char *buf;
180	unsigned char cts_enable_byte = 0;
181	speed_t speed;
182
183	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
184	if (buf == NULL)
185		return -ENOMEM;
186
187	divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
188	put_unaligned_le32(divisor, buf);
189	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
190				MCT_U232_SET_BAUD_RATE_REQUEST,
191				MCT_U232_SET_REQUEST_TYPE,
192				0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
193				WDR_TIMEOUT);
194	if (rc < 0)	/*FIXME: What value speed results */
195		dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
196			value, rc);
197	else
198		tty_encode_baud_rate(tty, speed, speed);
199	dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
200
201	/* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
202	   always sends two extra USB 'device request' messages after the
203	   'baud rate change' message.  The actual functionality of the
204	   request codes in these messages is not fully understood but these
205	   particular codes are never seen in any operation besides a baud
206	   rate change.  Both of these messages send a single byte of data.
207	   In the first message, the value of this byte is always zero.
208
209	   The second message has been determined experimentally to control
210	   whether data will be transmitted to a device which is not asserting
211	   the 'CTS' signal.  If the second message's data byte is zero, data
212	   will be transmitted even if 'CTS' is not asserted (i.e. no hardware
213	   flow control).  if the second message's data byte is nonzero (a
214	   value of 1 is used by this driver), data will not be transmitted to
215	   a device which is not asserting 'CTS'.
216	*/
217
218	buf[0] = 0;
219	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
220				MCT_U232_SET_UNKNOWN1_REQUEST,
221				MCT_U232_SET_REQUEST_TYPE,
222				0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
223				WDR_TIMEOUT);
224	if (rc < 0)
225		dev_err(&port->dev, "Sending USB device request code %d "
226			"failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
227			rc);
228
229	if (port && C_CRTSCTS(tty))
230	   cts_enable_byte = 1;
231
232	dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
233		cts_enable_byte);
234	buf[0] = cts_enable_byte;
235	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
236			MCT_U232_SET_CTS_REQUEST,
237			MCT_U232_SET_REQUEST_TYPE,
238			0, 0, buf, MCT_U232_SET_CTS_SIZE,
239			WDR_TIMEOUT);
240	if (rc < 0)
241		dev_err(&port->dev, "Sending USB device request code %d "
242			"failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
243
244	kfree(buf);
245	return rc;
246} /* mct_u232_set_baud_rate */
247
248static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
249				  unsigned char lcr)
250{
251	int rc;
252	unsigned char *buf;
253
254	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
255	if (buf == NULL)
256		return -ENOMEM;
257
258	buf[0] = lcr;
259	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
260			MCT_U232_SET_LINE_CTRL_REQUEST,
261			MCT_U232_SET_REQUEST_TYPE,
262			0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
263			WDR_TIMEOUT);
264	if (rc < 0)
265		dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
266	dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
 
267	kfree(buf);
268	return rc;
269} /* mct_u232_set_line_ctrl */
270
271static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
272				   unsigned int control_state)
273{
274	int rc;
275	unsigned char mcr;
276	unsigned char *buf;
277
278	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
279	if (buf == NULL)
280		return -ENOMEM;
281
282	mcr = MCT_U232_MCR_NONE;
283	if (control_state & TIOCM_DTR)
284		mcr |= MCT_U232_MCR_DTR;
285	if (control_state & TIOCM_RTS)
286		mcr |= MCT_U232_MCR_RTS;
287
288	buf[0] = mcr;
289	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
290			MCT_U232_SET_MODEM_CTRL_REQUEST,
291			MCT_U232_SET_REQUEST_TYPE,
292			0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
293			WDR_TIMEOUT);
294	kfree(buf);
295
296	dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
297
298	if (rc < 0) {
299		dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
 
300		return rc;
301	}
302	return 0;
303} /* mct_u232_set_modem_ctrl */
304
305static int mct_u232_get_modem_stat(struct usb_serial_port *port,
306				   unsigned char *msr)
307{
308	int rc;
309	unsigned char *buf;
310
311	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
312	if (buf == NULL) {
313		*msr = 0;
314		return -ENOMEM;
315	}
316	rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
317			MCT_U232_GET_MODEM_STAT_REQUEST,
318			MCT_U232_GET_REQUEST_TYPE,
319			0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
320			WDR_TIMEOUT);
321	if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
322		dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
323
324		if (rc >= 0)
325			rc = -EIO;
326
327		*msr = 0;
328	} else {
329		*msr = buf[0];
330	}
331	dev_dbg(&port->dev, "get_modem_stat: 0x%x\n", *msr);
332	kfree(buf);
333	return rc;
334} /* mct_u232_get_modem_stat */
335
336static void mct_u232_msr_to_icount(struct async_icount *icount,
337						unsigned char msr)
338{
339	/* Translate Control Line states */
340	if (msr & MCT_U232_MSR_DDSR)
341		icount->dsr++;
342	if (msr & MCT_U232_MSR_DCTS)
343		icount->cts++;
344	if (msr & MCT_U232_MSR_DRI)
345		icount->rng++;
346	if (msr & MCT_U232_MSR_DCD)
347		icount->dcd++;
348} /* mct_u232_msr_to_icount */
349
350static void mct_u232_msr_to_state(struct usb_serial_port *port,
351				  unsigned int *control_state, unsigned char msr)
352{
353	/* Translate Control Line states */
354	if (msr & MCT_U232_MSR_DSR)
355		*control_state |=  TIOCM_DSR;
356	else
357		*control_state &= ~TIOCM_DSR;
358	if (msr & MCT_U232_MSR_CTS)
359		*control_state |=  TIOCM_CTS;
360	else
361		*control_state &= ~TIOCM_CTS;
362	if (msr & MCT_U232_MSR_RI)
363		*control_state |=  TIOCM_RI;
364	else
365		*control_state &= ~TIOCM_RI;
366	if (msr & MCT_U232_MSR_CD)
367		*control_state |=  TIOCM_CD;
368	else
369		*control_state &= ~TIOCM_CD;
370	dev_dbg(&port->dev, "msr_to_state: msr=0x%x ==> state=0x%x\n", msr, *control_state);
371} /* mct_u232_msr_to_state */
372
373/*
374 * Driver's tty interface functions
375 */
376
377static int mct_u232_port_probe(struct usb_serial_port *port)
378{
379	struct usb_serial *serial = port->serial;
380	struct mct_u232_private *priv;
 
381
382	/* check first to simplify error handling */
383	if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) {
384		dev_err(&port->dev, "expected endpoint missing\n");
385		return -ENODEV;
386	}
387
388	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
389	if (!priv)
390		return -ENOMEM;
391
392	/* Use second interrupt-in endpoint for reading. */
393	priv->read_urb = serial->port[1]->interrupt_in_urb;
394	priv->read_urb->context = port;
395
396	spin_lock_init(&priv->lock);
 
 
 
 
397
398	usb_set_serial_port_data(port, priv);
 
 
 
 
 
 
 
399
400	return 0;
401}
 
402
403static int mct_u232_port_remove(struct usb_serial_port *port)
404{
405	struct mct_u232_private *priv;
 
406
407	priv = usb_get_serial_port_data(port);
408	kfree(priv);
409
410	return 0;
411}
 
412
413static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
414{
415	struct usb_serial *serial = port->serial;
416	struct mct_u232_private *priv = usb_get_serial_port_data(port);
417	int retval = 0;
418	unsigned int control_state;
419	unsigned long flags;
420	unsigned char last_lcr;
421	unsigned char last_msr;
422
423	/* Compensate for a hardware bug: although the Sitecom U232-P25
424	 * device reports a maximum output packet size of 32 bytes,
425	 * it seems to be able to accept only 16 bytes (and that's what
426	 * SniffUSB says too...)
427	 */
428	if (le16_to_cpu(serial->dev->descriptor.idProduct)
429						== MCT_U232_SITECOM_PID)
430		port->bulk_out_size = 16;
431
432	/* Do a defined restart: the normal serial device seems to
433	 * always turn on DTR and RTS here, so do the same. I'm not
434	 * sure if this is really necessary. But it should not harm
435	 * either.
436	 */
437	spin_lock_irqsave(&priv->lock, flags);
438	if (tty && C_BAUD(tty))
439		priv->control_state = TIOCM_DTR | TIOCM_RTS;
440	else
441		priv->control_state = 0;
442
443	priv->last_lcr = (MCT_U232_DATA_BITS_8 |
444			  MCT_U232_PARITY_NONE |
445			  MCT_U232_STOP_BITS_1);
446	control_state = priv->control_state;
447	last_lcr = priv->last_lcr;
448	spin_unlock_irqrestore(&priv->lock, flags);
449	mct_u232_set_modem_ctrl(port, control_state);
450	mct_u232_set_line_ctrl(port, last_lcr);
451
452	/* Read modem status and update control state */
453	mct_u232_get_modem_stat(port, &last_msr);
454	spin_lock_irqsave(&priv->lock, flags);
455	priv->last_msr = last_msr;
456	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
457	spin_unlock_irqrestore(&priv->lock, flags);
458
459	retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
460	if (retval) {
461		dev_err(&port->dev,
462			"usb_submit_urb(read) failed pipe 0x%x err %d\n",
463			port->read_urb->pipe, retval);
464		goto error;
465	}
466
467	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
468	if (retval) {
469		usb_kill_urb(priv->read_urb);
470		dev_err(&port->dev,
471			"usb_submit_urb(read int) failed pipe 0x%x err %d",
472			port->interrupt_in_urb->pipe, retval);
473		goto error;
474	}
475	return 0;
476
477error:
478	return retval;
479} /* mct_u232_open */
480
481static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
482{
483	unsigned int control_state;
484	struct mct_u232_private *priv = usb_get_serial_port_data(port);
485
486	spin_lock_irq(&priv->lock);
487	if (on)
488		priv->control_state |= TIOCM_DTR | TIOCM_RTS;
489	else
490		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
491	control_state = priv->control_state;
492	spin_unlock_irq(&priv->lock);
493
494	mct_u232_set_modem_ctrl(port, control_state);
 
 
 
 
495}
496
497static void mct_u232_close(struct usb_serial_port *port)
498{
499	struct mct_u232_private *priv = usb_get_serial_port_data(port);
500
501	usb_kill_urb(priv->read_urb);
502	usb_kill_urb(port->interrupt_in_urb);
503
504	usb_serial_generic_close(port);
505} /* mct_u232_close */
506
507
508static void mct_u232_read_int_callback(struct urb *urb)
509{
510	struct usb_serial_port *port = urb->context;
511	struct mct_u232_private *priv = usb_get_serial_port_data(port);
 
 
512	unsigned char *data = urb->transfer_buffer;
513	int retval;
514	int status = urb->status;
515	unsigned long flags;
516
517	switch (status) {
518	case 0:
519		/* success */
520		break;
521	case -ECONNRESET:
522	case -ENOENT:
523	case -ESHUTDOWN:
524		/* this urb is terminated, clean up */
525		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
526			__func__, status);
527		return;
528	default:
529		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
530			__func__, status);
531		goto exit;
532	}
533
534	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 
 
 
 
 
 
535
536	/*
537	 * Work-a-round: handle the 'usual' bulk-in pipe here
538	 */
539	if (urb->transfer_buffer_length > 2) {
540		if (urb->actual_length) {
541			tty_insert_flip_string(&port->port, data,
542					urb->actual_length);
543			tty_flip_buffer_push(&port->port);
 
 
 
 
544		}
545		goto exit;
546	}
547
548	/*
549	 * The interrupt-in pipe signals exceptional conditions (modem line
550	 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
551	 */
552	spin_lock_irqsave(&priv->lock, flags);
553	priv->last_msr = data[MCT_U232_MSR_INDEX];
554
555	/* Record Control Line states */
556	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
557
558	mct_u232_msr_to_icount(&port->icount, priv->last_msr);
559
560#if 0
561	/* Not yet handled. See belkin_sa.c for further information */
562	/* Now to report any errors */
563	priv->last_lsr = data[MCT_U232_LSR_INDEX];
564	/*
565	 * fill in the flip buffer here, but I do not know the relation
566	 * to the current/next receive buffer or characters.  I need
567	 * to look in to this before committing any code.
568	 */
569	if (priv->last_lsr & MCT_U232_LSR_ERR) {
570		tty = tty_port_tty_get(&port->port);
571		/* Overrun Error */
572		if (priv->last_lsr & MCT_U232_LSR_OE) {
573		}
574		/* Parity Error */
575		if (priv->last_lsr & MCT_U232_LSR_PE) {
576		}
577		/* Framing Error */
578		if (priv->last_lsr & MCT_U232_LSR_FE) {
579		}
580		/* Break Indicator */
581		if (priv->last_lsr & MCT_U232_LSR_BI) {
582		}
583		tty_kref_put(tty);
584	}
585#endif
586	wake_up_interruptible(&port->port.delta_msr_wait);
587	spin_unlock_irqrestore(&priv->lock, flags);
588exit:
589	retval = usb_submit_urb(urb, GFP_ATOMIC);
590	if (retval)
591		dev_err(&port->dev,
592			"%s - usb_submit_urb failed with result %d\n",
593			__func__, retval);
594} /* mct_u232_read_int_callback */
595
596static void mct_u232_set_termios(struct tty_struct *tty,
597				 struct usb_serial_port *port,
598				 struct ktermios *old_termios)
599{
600	struct usb_serial *serial = port->serial;
601	struct mct_u232_private *priv = usb_get_serial_port_data(port);
602	struct ktermios *termios = &tty->termios;
603	unsigned int cflag = termios->c_cflag;
604	unsigned int old_cflag = old_termios->c_cflag;
605	unsigned long flags;
606	unsigned int control_state;
607	unsigned char last_lcr;
608
609	/* get a local copy of the current port settings */
610	spin_lock_irqsave(&priv->lock, flags);
611	control_state = priv->control_state;
612	spin_unlock_irqrestore(&priv->lock, flags);
613	last_lcr = 0;
614
615	/*
616	 * Update baud rate.
617	 * Do not attempt to cache old rates and skip settings,
618	 * disconnects screw such tricks up completely.
619	 * Premature optimization is the root of all evil.
620	 */
621
622	/* reassert DTR and RTS on transition from B0 */
623	if ((old_cflag & CBAUD) == B0) {
624		dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
625		control_state |= TIOCM_DTR | TIOCM_RTS;
626		mct_u232_set_modem_ctrl(port, control_state);
627	}
628
629	mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
630
631	if ((cflag & CBAUD) == B0) {
632		dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
633		/* Drop RTS and DTR */
634		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
635		mct_u232_set_modem_ctrl(port, control_state);
636	}
637
638	/*
639	 * Update line control register (LCR)
640	 */
641
642	/* set the parity */
643	if (cflag & PARENB)
644		last_lcr |= (cflag & PARODD) ?
645			MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
646	else
647		last_lcr |= MCT_U232_PARITY_NONE;
648
649	/* set the number of data bits */
650	switch (cflag & CSIZE) {
651	case CS5:
652		last_lcr |= MCT_U232_DATA_BITS_5; break;
653	case CS6:
654		last_lcr |= MCT_U232_DATA_BITS_6; break;
655	case CS7:
656		last_lcr |= MCT_U232_DATA_BITS_7; break;
657	case CS8:
658		last_lcr |= MCT_U232_DATA_BITS_8; break;
659	default:
660		dev_err(&port->dev,
661			"CSIZE was not CS5-CS8, using default of 8\n");
662		last_lcr |= MCT_U232_DATA_BITS_8;
663		break;
664	}
665
666	termios->c_cflag &= ~CMSPAR;
667
668	/* set the number of stop bits */
669	last_lcr |= (cflag & CSTOPB) ?
670		MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
671
672	mct_u232_set_line_ctrl(port, last_lcr);
673
674	/* save off the modified port settings */
675	spin_lock_irqsave(&priv->lock, flags);
676	priv->control_state = control_state;
677	priv->last_lcr = last_lcr;
678	spin_unlock_irqrestore(&priv->lock, flags);
679} /* mct_u232_set_termios */
680
681static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
682{
683	struct usb_serial_port *port = tty->driver_data;
 
684	struct mct_u232_private *priv = usb_get_serial_port_data(port);
685	unsigned char lcr;
686	unsigned long flags;
687
688	spin_lock_irqsave(&priv->lock, flags);
689	lcr = priv->last_lcr;
690
691	if (break_state)
692		lcr |= MCT_U232_SET_BREAK;
693	spin_unlock_irqrestore(&priv->lock, flags);
694
695	mct_u232_set_line_ctrl(port, lcr);
696} /* mct_u232_break_ctl */
697
698
699static int mct_u232_tiocmget(struct tty_struct *tty)
700{
701	struct usb_serial_port *port = tty->driver_data;
702	struct mct_u232_private *priv = usb_get_serial_port_data(port);
703	unsigned int control_state;
704	unsigned long flags;
705
706	spin_lock_irqsave(&priv->lock, flags);
707	control_state = priv->control_state;
708	spin_unlock_irqrestore(&priv->lock, flags);
709
710	return control_state;
711}
712
713static int mct_u232_tiocmset(struct tty_struct *tty,
714			      unsigned int set, unsigned int clear)
715{
716	struct usb_serial_port *port = tty->driver_data;
 
717	struct mct_u232_private *priv = usb_get_serial_port_data(port);
718	unsigned int control_state;
719	unsigned long flags;
720
721	spin_lock_irqsave(&priv->lock, flags);
722	control_state = priv->control_state;
723
724	if (set & TIOCM_RTS)
725		control_state |= TIOCM_RTS;
726	if (set & TIOCM_DTR)
727		control_state |= TIOCM_DTR;
728	if (clear & TIOCM_RTS)
729		control_state &= ~TIOCM_RTS;
730	if (clear & TIOCM_DTR)
731		control_state &= ~TIOCM_DTR;
732
733	priv->control_state = control_state;
734	spin_unlock_irqrestore(&priv->lock, flags);
735	return mct_u232_set_modem_ctrl(port, control_state);
736}
737
738static void mct_u232_throttle(struct tty_struct *tty)
739{
740	struct usb_serial_port *port = tty->driver_data;
741	struct mct_u232_private *priv = usb_get_serial_port_data(port);
742	unsigned int control_state;
743
744	spin_lock_irq(&priv->lock);
745	priv->rx_flags |= THROTTLED;
746	if (C_CRTSCTS(tty)) {
747		priv->control_state &= ~TIOCM_RTS;
748		control_state = priv->control_state;
749		spin_unlock_irq(&priv->lock);
750		mct_u232_set_modem_ctrl(port, control_state);
751	} else {
752		spin_unlock_irq(&priv->lock);
753	}
754}
755
756static void mct_u232_unthrottle(struct tty_struct *tty)
757{
758	struct usb_serial_port *port = tty->driver_data;
759	struct mct_u232_private *priv = usb_get_serial_port_data(port);
760	unsigned int control_state;
761
762	spin_lock_irq(&priv->lock);
763	if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
764		priv->rx_flags &= ~THROTTLED;
765		priv->control_state |= TIOCM_RTS;
766		control_state = priv->control_state;
767		spin_unlock_irq(&priv->lock);
768		mct_u232_set_modem_ctrl(port, control_state);
769	} else {
770		spin_unlock_irq(&priv->lock);
771	}
772}
773
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
774module_usb_serial_driver(serial_drivers, id_table);
775
776MODULE_AUTHOR(DRIVER_AUTHOR);
777MODULE_DESCRIPTION(DRIVER_DESC);
778MODULE_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");