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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");
v3.15
 
  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/slab.h>
 27#include <linux/tty.h>
 28#include <linux/tty_driver.h>
 29#include <linux/tty_flip.h>
 30#include <linux/module.h>
 31#include <linux/spinlock.h>
 32#include <linux/uaccess.h>
 33#include <asm/unaligned.h>
 34#include <linux/usb.h>
 35#include <linux/usb/serial.h>
 36#include <linux/serial.h>
 37#include "mct_u232.h"
 38
 39#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
 40#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
 41
 42/*
 43 * Function prototypes
 44 */
 45static int  mct_u232_port_probe(struct usb_serial_port *port);
 46static int  mct_u232_port_remove(struct usb_serial_port *remove);
 47static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
 48static void mct_u232_close(struct usb_serial_port *port);
 49static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
 50static void mct_u232_read_int_callback(struct urb *urb);
 51static void mct_u232_set_termios(struct tty_struct *tty,
 52			struct usb_serial_port *port, struct ktermios *old);
 53static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
 54static int  mct_u232_tiocmget(struct tty_struct *tty);
 55static int  mct_u232_tiocmset(struct tty_struct *tty,
 56			unsigned int set, unsigned int clear);
 57static void mct_u232_throttle(struct tty_struct *tty);
 58static void mct_u232_unthrottle(struct tty_struct *tty);
 59
 60
 61/*
 62 * All of the device info needed for the MCT USB-RS232 converter.
 63 */
 64static const struct usb_device_id id_table[] = {
 65	{ USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
 66	{ USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
 67	{ USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
 68	{ USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
 69	{ }		/* Terminating entry */
 70};
 71MODULE_DEVICE_TABLE(usb, id_table);
 72
 73static struct usb_serial_driver mct_u232_device = {
 74	.driver = {
 75		.owner =	THIS_MODULE,
 76		.name =		"mct_u232",
 77	},
 78	.description =	     "MCT U232",
 79	.id_table =	     id_table,
 80	.num_ports =	     1,
 81	.open =		     mct_u232_open,
 82	.close =	     mct_u232_close,
 83	.dtr_rts =	     mct_u232_dtr_rts,
 84	.throttle =	     mct_u232_throttle,
 85	.unthrottle =	     mct_u232_unthrottle,
 86	.read_int_callback = mct_u232_read_int_callback,
 87	.set_termios =	     mct_u232_set_termios,
 88	.break_ctl =	     mct_u232_break_ctl,
 89	.tiocmget =	     mct_u232_tiocmget,
 90	.tiocmset =	     mct_u232_tiocmset,
 91	.tiocmiwait =        usb_serial_generic_tiocmiwait,
 92	.port_probe =        mct_u232_port_probe,
 93	.port_remove =       mct_u232_port_remove,
 94	.get_icount =        usb_serial_generic_get_icount,
 95};
 96
 97static struct usb_serial_driver * const serial_drivers[] = {
 98	&mct_u232_device, NULL
 99};
100
101struct mct_u232_private {
102	struct urb *read_urb;
103	spinlock_t lock;
104	unsigned int	     control_state; /* Modem Line Setting (TIOCM) */
105	unsigned char        last_lcr;      /* Line Control Register */
106	unsigned char	     last_lsr;      /* Line Status Register */
107	unsigned char	     last_msr;      /* Modem Status Register */
108	unsigned int	     rx_flags;      /* Throttling flags */
109};
110
111#define THROTTLED		0x01
112
113/*
114 * Handle vendor specific USB requests
115 */
116
117#define WDR_TIMEOUT 5000 /* default urb timeout */
118
119/*
120 * Later day 2.6.0-test kernels have new baud rates like B230400 which
121 * we do not know how to support. We ignore them for the moment.
122 */
123static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
124					speed_t value, speed_t *result)
125{
126	*result = value;
127
128	if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
129		|| le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
130		switch (value) {
131		case 300:
132			return 0x01;
133		case 600:
134			return 0x02; /* this one not tested */
135		case 1200:
136			return 0x03;
137		case 2400:
138			return 0x04;
139		case 4800:
140			return 0x06;
141		case 9600:
142			return 0x08;
143		case 19200:
144			return 0x09;
145		case 38400:
146			return 0x0a;
147		case 57600:
148			return 0x0b;
149		case 115200:
150			return 0x0c;
151		default:
152			*result = 9600;
153			return 0x08;
154		}
155	} else {
156		/* FIXME: Can we use any divider - should we do
157		   divider = 115200/value;
158		   real baud = 115200/divider */
159		switch (value) {
160		case 300: break;
161		case 600: break;
162		case 1200: break;
163		case 2400: break;
164		case 4800: break;
165		case 9600: break;
166		case 19200: break;
167		case 38400: break;
168		case 57600: break;
169		case 115200: break;
170		default:
171			value = 9600;
172			*result = 9600;
173		}
174		return 115200/value;
175	}
176}
177
178static int mct_u232_set_baud_rate(struct tty_struct *tty,
179	struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
180{
181	unsigned int divisor;
182	int rc;
183	unsigned char *buf;
184	unsigned char cts_enable_byte = 0;
185	speed_t speed;
186
187	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
188	if (buf == NULL)
189		return -ENOMEM;
190
191	divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
192	put_unaligned_le32(cpu_to_le32(divisor), buf);
193	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
194				MCT_U232_SET_BAUD_RATE_REQUEST,
195				MCT_U232_SET_REQUEST_TYPE,
196				0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
197				WDR_TIMEOUT);
198	if (rc < 0)	/*FIXME: What value speed results */
199		dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
200			value, rc);
201	else
202		tty_encode_baud_rate(tty, speed, speed);
203	dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
204
205	/* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
206	   always sends two extra USB 'device request' messages after the
207	   'baud rate change' message.  The actual functionality of the
208	   request codes in these messages is not fully understood but these
209	   particular codes are never seen in any operation besides a baud
210	   rate change.  Both of these messages send a single byte of data.
211	   In the first message, the value of this byte is always zero.
212
213	   The second message has been determined experimentally to control
214	   whether data will be transmitted to a device which is not asserting
215	   the 'CTS' signal.  If the second message's data byte is zero, data
216	   will be transmitted even if 'CTS' is not asserted (i.e. no hardware
217	   flow control).  if the second message's data byte is nonzero (a
218	   value of 1 is used by this driver), data will not be transmitted to
219	   a device which is not asserting 'CTS'.
220	*/
221
222	buf[0] = 0;
223	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
224				MCT_U232_SET_UNKNOWN1_REQUEST,
225				MCT_U232_SET_REQUEST_TYPE,
226				0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
227				WDR_TIMEOUT);
228	if (rc < 0)
229		dev_err(&port->dev, "Sending USB device request code %d "
230			"failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
231			rc);
232
233	if (port && C_CRTSCTS(tty))
234	   cts_enable_byte = 1;
235
236	dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
237		cts_enable_byte);
238	buf[0] = cts_enable_byte;
239	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
240			MCT_U232_SET_CTS_REQUEST,
241			MCT_U232_SET_REQUEST_TYPE,
242			0, 0, buf, MCT_U232_SET_CTS_SIZE,
243			WDR_TIMEOUT);
244	if (rc < 0)
245		dev_err(&port->dev, "Sending USB device request code %d "
246			"failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
247
248	kfree(buf);
249	return rc;
250} /* mct_u232_set_baud_rate */
251
252static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
253				  unsigned char lcr)
254{
255	int rc;
256	unsigned char *buf;
257
258	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
259	if (buf == NULL)
260		return -ENOMEM;
261
262	buf[0] = lcr;
263	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
264			MCT_U232_SET_LINE_CTRL_REQUEST,
265			MCT_U232_SET_REQUEST_TYPE,
266			0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
267			WDR_TIMEOUT);
268	if (rc < 0)
269		dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
270	dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
271	kfree(buf);
272	return rc;
273} /* mct_u232_set_line_ctrl */
274
275static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
276				   unsigned int control_state)
277{
278	int rc;
279	unsigned char mcr;
280	unsigned char *buf;
281
282	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
283	if (buf == NULL)
284		return -ENOMEM;
285
286	mcr = MCT_U232_MCR_NONE;
287	if (control_state & TIOCM_DTR)
288		mcr |= MCT_U232_MCR_DTR;
289	if (control_state & TIOCM_RTS)
290		mcr |= MCT_U232_MCR_RTS;
291
292	buf[0] = mcr;
293	rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
294			MCT_U232_SET_MODEM_CTRL_REQUEST,
295			MCT_U232_SET_REQUEST_TYPE,
296			0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
297			WDR_TIMEOUT);
298	kfree(buf);
299
300	dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
301
302	if (rc < 0) {
303		dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
304		return rc;
305	}
306	return 0;
307} /* mct_u232_set_modem_ctrl */
308
309static int mct_u232_get_modem_stat(struct usb_serial_port *port,
310				   unsigned char *msr)
311{
312	int rc;
313	unsigned char *buf;
314
315	buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
316	if (buf == NULL) {
317		*msr = 0;
318		return -ENOMEM;
319	}
320	rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
321			MCT_U232_GET_MODEM_STAT_REQUEST,
322			MCT_U232_GET_REQUEST_TYPE,
323			0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
324			WDR_TIMEOUT);
325	if (rc < 0) {
326		dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
 
 
 
 
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 mct_u232_private *priv;
380
 
 
 
 
 
 
381	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
382	if (!priv)
383		return -ENOMEM;
384
385	/* Use second interrupt-in endpoint for reading. */
386	priv->read_urb = port->serial->port[1]->interrupt_in_urb;
387	priv->read_urb->context = port;
388
389	spin_lock_init(&priv->lock);
390
391	usb_set_serial_port_data(port, priv);
392
393	return 0;
394}
395
396static int mct_u232_port_remove(struct usb_serial_port *port)
397{
398	struct mct_u232_private *priv;
399
400	priv = usb_get_serial_port_data(port);
401	kfree(priv);
402
403	return 0;
404}
405
406static int  mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
407{
408	struct usb_serial *serial = port->serial;
409	struct mct_u232_private *priv = usb_get_serial_port_data(port);
410	int retval = 0;
411	unsigned int control_state;
412	unsigned long flags;
413	unsigned char last_lcr;
414	unsigned char last_msr;
415
416	/* Compensate for a hardware bug: although the Sitecom U232-P25
417	 * device reports a maximum output packet size of 32 bytes,
418	 * it seems to be able to accept only 16 bytes (and that's what
419	 * SniffUSB says too...)
420	 */
421	if (le16_to_cpu(serial->dev->descriptor.idProduct)
422						== MCT_U232_SITECOM_PID)
423		port->bulk_out_size = 16;
424
425	/* Do a defined restart: the normal serial device seems to
426	 * always turn on DTR and RTS here, so do the same. I'm not
427	 * sure if this is really necessary. But it should not harm
428	 * either.
429	 */
430	spin_lock_irqsave(&priv->lock, flags);
431	if (tty && (tty->termios.c_cflag & CBAUD))
432		priv->control_state = TIOCM_DTR | TIOCM_RTS;
433	else
434		priv->control_state = 0;
435
436	priv->last_lcr = (MCT_U232_DATA_BITS_8 |
437			  MCT_U232_PARITY_NONE |
438			  MCT_U232_STOP_BITS_1);
439	control_state = priv->control_state;
440	last_lcr = priv->last_lcr;
441	spin_unlock_irqrestore(&priv->lock, flags);
442	mct_u232_set_modem_ctrl(port, control_state);
443	mct_u232_set_line_ctrl(port, last_lcr);
444
445	/* Read modem status and update control state */
446	mct_u232_get_modem_stat(port, &last_msr);
447	spin_lock_irqsave(&priv->lock, flags);
448	priv->last_msr = last_msr;
449	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
450	spin_unlock_irqrestore(&priv->lock, flags);
451
452	retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
453	if (retval) {
454		dev_err(&port->dev,
455			"usb_submit_urb(read) failed pipe 0x%x err %d\n",
456			port->read_urb->pipe, retval);
457		goto error;
458	}
459
460	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
461	if (retval) {
462		usb_kill_urb(priv->read_urb);
463		dev_err(&port->dev,
464			"usb_submit_urb(read int) failed pipe 0x%x err %d",
465			port->interrupt_in_urb->pipe, retval);
466		goto error;
467	}
468	return 0;
469
470error:
471	return retval;
472} /* mct_u232_open */
473
474static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
475{
476	unsigned int control_state;
477	struct mct_u232_private *priv = usb_get_serial_port_data(port);
478
479	spin_lock_irq(&priv->lock);
480	if (on)
481		priv->control_state |= TIOCM_DTR | TIOCM_RTS;
482	else
483		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
484	control_state = priv->control_state;
485	spin_unlock_irq(&priv->lock);
486
487	mct_u232_set_modem_ctrl(port, control_state);
488}
489
490static void mct_u232_close(struct usb_serial_port *port)
491{
492	struct mct_u232_private *priv = usb_get_serial_port_data(port);
493
494	usb_kill_urb(priv->read_urb);
495	usb_kill_urb(port->interrupt_in_urb);
496
497	usb_serial_generic_close(port);
498} /* mct_u232_close */
499
500
501static void mct_u232_read_int_callback(struct urb *urb)
502{
503	struct usb_serial_port *port = urb->context;
504	struct mct_u232_private *priv = usb_get_serial_port_data(port);
505	unsigned char *data = urb->transfer_buffer;
506	int retval;
507	int status = urb->status;
508	unsigned long flags;
509
510	switch (status) {
511	case 0:
512		/* success */
513		break;
514	case -ECONNRESET:
515	case -ENOENT:
516	case -ESHUTDOWN:
517		/* this urb is terminated, clean up */
518		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
519			__func__, status);
520		return;
521	default:
522		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
523			__func__, status);
524		goto exit;
525	}
526
527	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
528
529	/*
530	 * Work-a-round: handle the 'usual' bulk-in pipe here
531	 */
532	if (urb->transfer_buffer_length > 2) {
533		if (urb->actual_length) {
534			tty_insert_flip_string(&port->port, data,
535					urb->actual_length);
536			tty_flip_buffer_push(&port->port);
537		}
538		goto exit;
539	}
540
541	/*
542	 * The interrupt-in pipe signals exceptional conditions (modem line
543	 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
544	 */
545	spin_lock_irqsave(&priv->lock, flags);
546	priv->last_msr = data[MCT_U232_MSR_INDEX];
547
548	/* Record Control Line states */
549	mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
550
551	mct_u232_msr_to_icount(&port->icount, priv->last_msr);
552
553#if 0
554	/* Not yet handled. See belkin_sa.c for further information */
555	/* Now to report any errors */
556	priv->last_lsr = data[MCT_U232_LSR_INDEX];
557	/*
558	 * fill in the flip buffer here, but I do not know the relation
559	 * to the current/next receive buffer or characters.  I need
560	 * to look in to this before committing any code.
561	 */
562	if (priv->last_lsr & MCT_U232_LSR_ERR) {
563		tty = tty_port_tty_get(&port->port);
564		/* Overrun Error */
565		if (priv->last_lsr & MCT_U232_LSR_OE) {
566		}
567		/* Parity Error */
568		if (priv->last_lsr & MCT_U232_LSR_PE) {
569		}
570		/* Framing Error */
571		if (priv->last_lsr & MCT_U232_LSR_FE) {
572		}
573		/* Break Indicator */
574		if (priv->last_lsr & MCT_U232_LSR_BI) {
575		}
576		tty_kref_put(tty);
577	}
578#endif
579	wake_up_interruptible(&port->port.delta_msr_wait);
580	spin_unlock_irqrestore(&priv->lock, flags);
581exit:
582	retval = usb_submit_urb(urb, GFP_ATOMIC);
583	if (retval)
584		dev_err(&port->dev,
585			"%s - usb_submit_urb failed with result %d\n",
586			__func__, retval);
587} /* mct_u232_read_int_callback */
588
589static void mct_u232_set_termios(struct tty_struct *tty,
590				 struct usb_serial_port *port,
591				 struct ktermios *old_termios)
592{
593	struct usb_serial *serial = port->serial;
594	struct mct_u232_private *priv = usb_get_serial_port_data(port);
595	struct ktermios *termios = &tty->termios;
596	unsigned int cflag = termios->c_cflag;
597	unsigned int old_cflag = old_termios->c_cflag;
598	unsigned long flags;
599	unsigned int control_state;
600	unsigned char last_lcr;
601
602	/* get a local copy of the current port settings */
603	spin_lock_irqsave(&priv->lock, flags);
604	control_state = priv->control_state;
605	spin_unlock_irqrestore(&priv->lock, flags);
606	last_lcr = 0;
607
608	/*
609	 * Update baud rate.
610	 * Do not attempt to cache old rates and skip settings,
611	 * disconnects screw such tricks up completely.
612	 * Premature optimization is the root of all evil.
613	 */
614
615	/* reassert DTR and RTS on transition from B0 */
616	if ((old_cflag & CBAUD) == B0) {
617		dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
618		control_state |= TIOCM_DTR | TIOCM_RTS;
619		mct_u232_set_modem_ctrl(port, control_state);
620	}
621
622	mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
623
624	if ((cflag & CBAUD) == B0) {
625		dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
626		/* Drop RTS and DTR */
627		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
628		mct_u232_set_modem_ctrl(port, control_state);
629	}
630
631	/*
632	 * Update line control register (LCR)
633	 */
634
635	/* set the parity */
636	if (cflag & PARENB)
637		last_lcr |= (cflag & PARODD) ?
638			MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
639	else
640		last_lcr |= MCT_U232_PARITY_NONE;
641
642	/* set the number of data bits */
643	switch (cflag & CSIZE) {
644	case CS5:
645		last_lcr |= MCT_U232_DATA_BITS_5; break;
646	case CS6:
647		last_lcr |= MCT_U232_DATA_BITS_6; break;
648	case CS7:
649		last_lcr |= MCT_U232_DATA_BITS_7; break;
650	case CS8:
651		last_lcr |= MCT_U232_DATA_BITS_8; break;
652	default:
653		dev_err(&port->dev,
654			"CSIZE was not CS5-CS8, using default of 8\n");
655		last_lcr |= MCT_U232_DATA_BITS_8;
656		break;
657	}
658
659	termios->c_cflag &= ~CMSPAR;
660
661	/* set the number of stop bits */
662	last_lcr |= (cflag & CSTOPB) ?
663		MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
664
665	mct_u232_set_line_ctrl(port, last_lcr);
666
667	/* save off the modified port settings */
668	spin_lock_irqsave(&priv->lock, flags);
669	priv->control_state = control_state;
670	priv->last_lcr = last_lcr;
671	spin_unlock_irqrestore(&priv->lock, flags);
672} /* mct_u232_set_termios */
673
674static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
675{
676	struct usb_serial_port *port = tty->driver_data;
677	struct mct_u232_private *priv = usb_get_serial_port_data(port);
678	unsigned char lcr;
679	unsigned long flags;
680
681	spin_lock_irqsave(&priv->lock, flags);
682	lcr = priv->last_lcr;
683
684	if (break_state)
685		lcr |= MCT_U232_SET_BREAK;
686	spin_unlock_irqrestore(&priv->lock, flags);
687
688	mct_u232_set_line_ctrl(port, lcr);
689} /* mct_u232_break_ctl */
690
691
692static int mct_u232_tiocmget(struct tty_struct *tty)
693{
694	struct usb_serial_port *port = tty->driver_data;
695	struct mct_u232_private *priv = usb_get_serial_port_data(port);
696	unsigned int control_state;
697	unsigned long flags;
698
699	spin_lock_irqsave(&priv->lock, flags);
700	control_state = priv->control_state;
701	spin_unlock_irqrestore(&priv->lock, flags);
702
703	return control_state;
704}
705
706static int mct_u232_tiocmset(struct tty_struct *tty,
707			      unsigned int set, unsigned int clear)
708{
709	struct usb_serial_port *port = tty->driver_data;
710	struct mct_u232_private *priv = usb_get_serial_port_data(port);
711	unsigned int control_state;
712	unsigned long flags;
713
714	spin_lock_irqsave(&priv->lock, flags);
715	control_state = priv->control_state;
716
717	if (set & TIOCM_RTS)
718		control_state |= TIOCM_RTS;
719	if (set & TIOCM_DTR)
720		control_state |= TIOCM_DTR;
721	if (clear & TIOCM_RTS)
722		control_state &= ~TIOCM_RTS;
723	if (clear & TIOCM_DTR)
724		control_state &= ~TIOCM_DTR;
725
726	priv->control_state = control_state;
727	spin_unlock_irqrestore(&priv->lock, flags);
728	return mct_u232_set_modem_ctrl(port, control_state);
729}
730
731static void mct_u232_throttle(struct tty_struct *tty)
732{
733	struct usb_serial_port *port = tty->driver_data;
734	struct mct_u232_private *priv = usb_get_serial_port_data(port);
735	unsigned int control_state;
736
737	spin_lock_irq(&priv->lock);
738	priv->rx_flags |= THROTTLED;
739	if (C_CRTSCTS(tty)) {
740		priv->control_state &= ~TIOCM_RTS;
741		control_state = priv->control_state;
742		spin_unlock_irq(&priv->lock);
743		mct_u232_set_modem_ctrl(port, control_state);
744	} else {
745		spin_unlock_irq(&priv->lock);
746	}
747}
748
749static void mct_u232_unthrottle(struct tty_struct *tty)
750{
751	struct usb_serial_port *port = tty->driver_data;
752	struct mct_u232_private *priv = usb_get_serial_port_data(port);
753	unsigned int control_state;
754
755	spin_lock_irq(&priv->lock);
756	if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
757		priv->rx_flags &= ~THROTTLED;
758		priv->control_state |= TIOCM_RTS;
759		control_state = priv->control_state;
760		spin_unlock_irq(&priv->lock);
761		mct_u232_set_modem_ctrl(port, control_state);
762	} else {
763		spin_unlock_irq(&priv->lock);
764	}
765}
766
767module_usb_serial_driver(serial_drivers, id_table);
768
769MODULE_AUTHOR(DRIVER_AUTHOR);
770MODULE_DESCRIPTION(DRIVER_DESC);
771MODULE_LICENSE("GPL");