xref: /linux/drivers/usb/serial/ssu100.c (revision c75c5ab575af7db707689cdbb5a5c458e9a034bb)
1 /*
2  * usb-serial driver for Quatech SSU-100
3  *
4  * based on ftdi_sio.c and the original serqt_usb.c from Quatech
5  *
6  */
7 
8 #include <linux/errno.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/tty.h>
12 #include <linux/tty_driver.h>
13 #include <linux/tty_flip.h>
14 #include <linux/module.h>
15 #include <linux/serial.h>
16 #include <linux/usb.h>
17 #include <linux/usb/serial.h>
18 #include <linux/serial_reg.h>
19 #include <linux/uaccess.h>
20 
21 #define QT_OPEN_CLOSE_CHANNEL       0xca
22 #define QT_SET_GET_DEVICE           0xc2
23 #define QT_SET_GET_REGISTER         0xc0
24 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
25 #define QT_SET_ATF                  0xcd
26 #define QT_GET_SET_UART             0xc1
27 #define QT_TRANSFER_IN              0xc0
28 #define QT_HW_FLOW_CONTROL_MASK     0xc5
29 #define QT_SW_FLOW_CONTROL_MASK     0xc6
30 
31 #define  SERIAL_MSR_MASK            0xf0
32 
33 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
34 
35 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
36 
37 #define  MAX_BAUD_RATE              460800
38 
39 #define ATC_DISABLED                0x00
40 #define DUPMODE_BITS        0xc0
41 #define RR_BITS             0x03
42 #define LOOPMODE_BITS       0x41
43 #define RS232_MODE          0x00
44 #define RTSCTS_TO_CONNECTOR 0x40
45 #define CLKS_X4             0x02
46 #define FULLPWRBIT          0x00000080
47 #define NEXT_BOARD_POWER_BIT        0x00000004
48 
49 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"
50 
51 #define	USB_VENDOR_ID_QUATECH	0x061d	/* Quatech VID */
52 #define QUATECH_SSU100	0xC020	/* SSU100 */
53 
54 static const struct usb_device_id id_table[] = {
55 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
56 	{}			/* Terminating entry */
57 };
58 MODULE_DEVICE_TABLE(usb, id_table);
59 
60 struct ssu100_port_private {
61 	spinlock_t status_lock;
62 	u8 shadowLSR;
63 	u8 shadowMSR;
64 	struct async_icount icount;
65 };
66 
67 static inline int ssu100_control_msg(struct usb_device *dev,
68 				     u8 request, u16 data, u16 index)
69 {
70 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
71 			       request, 0x40, data, index,
72 			       NULL, 0, 300);
73 }
74 
75 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data)
76 {
77 	u16 x = ((u16)(data[1] << 8) | (u16)(data[0]));
78 
79 	return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
80 }
81 
82 
83 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data)
84 {
85 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
86 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
87 			       data, 3, 300);
88 }
89 
90 static inline int ssu100_getregister(struct usb_device *dev,
91 				     unsigned short uart,
92 				     unsigned short reg,
93 				     u8 *data)
94 {
95 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
96 			       QT_SET_GET_REGISTER, 0xc0, reg,
97 			       uart, data, sizeof(*data), 300);
98 
99 }
100 
101 
102 static inline int ssu100_setregister(struct usb_device *dev,
103 				     unsigned short uart,
104 				     unsigned short reg,
105 				     u16 data)
106 {
107 	u16 value = (data << 8) | reg;
108 
109 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
110 			       QT_SET_GET_REGISTER, 0x40, value, uart,
111 			       NULL, 0, 300);
112 
113 }
114 
115 #define set_mctrl(dev, set)		update_mctrl((dev), (set), 0)
116 #define clear_mctrl(dev, clear)	update_mctrl((dev), 0, (clear))
117 
118 /* these do not deal with device that have more than 1 port */
119 static inline int update_mctrl(struct usb_device *dev, unsigned int set,
120 			       unsigned int clear)
121 {
122 	unsigned urb_value;
123 	int result;
124 
125 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
126 		dev_dbg(&dev->dev, "%s - DTR|RTS not being set|cleared\n", __func__);
127 		return 0;	/* no change */
128 	}
129 
130 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
131 	urb_value = 0;
132 	if (set & TIOCM_DTR)
133 		urb_value |= UART_MCR_DTR;
134 	if (set & TIOCM_RTS)
135 		urb_value |= UART_MCR_RTS;
136 
137 	result = ssu100_setregister(dev, 0, UART_MCR, urb_value);
138 	if (result < 0)
139 		dev_dbg(&dev->dev, "%s Error from MODEM_CTRL urb\n", __func__);
140 
141 	return result;
142 }
143 
144 static int ssu100_initdevice(struct usb_device *dev)
145 {
146 	u8 *data;
147 	int result = 0;
148 
149 	data = kzalloc(3, GFP_KERNEL);
150 	if (!data)
151 		return -ENOMEM;
152 
153 	result = ssu100_getdevice(dev, data);
154 	if (result < 0) {
155 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
156 		goto out;
157 	}
158 
159 	data[1] &= ~FULLPWRBIT;
160 
161 	result = ssu100_setdevice(dev, data);
162 	if (result < 0) {
163 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
164 		goto out;
165 	}
166 
167 	result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
168 	if (result < 0) {
169 		dev_dbg(&dev->dev, "%s - set prebuffer level failed %i\n", __func__, result);
170 		goto out;
171 	}
172 
173 	result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
174 	if (result < 0) {
175 		dev_dbg(&dev->dev, "%s - set ATFprebuffer level failed %i\n", __func__, result);
176 		goto out;
177 	}
178 
179 	result = ssu100_getdevice(dev, data);
180 	if (result < 0) {
181 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
182 		goto out;
183 	}
184 
185 	data[0] &= ~(RR_BITS | DUPMODE_BITS);
186 	data[0] |= CLKS_X4;
187 	data[1] &= ~(LOOPMODE_BITS);
188 	data[1] |= RS232_MODE;
189 
190 	result = ssu100_setdevice(dev, data);
191 	if (result < 0) {
192 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
193 		goto out;
194 	}
195 
196 out:	kfree(data);
197 	return result;
198 
199 }
200 
201 
202 static void ssu100_set_termios(struct tty_struct *tty,
203 			       struct usb_serial_port *port,
204 			       struct ktermios *old_termios)
205 {
206 	struct usb_device *dev = port->serial->dev;
207 	struct ktermios *termios = &tty->termios;
208 	u16 baud, divisor, remainder;
209 	unsigned int cflag = termios->c_cflag;
210 	u16 urb_value = 0; /* will hold the new flags */
211 	int result;
212 
213 	if (cflag & PARENB) {
214 		if (cflag & PARODD)
215 			urb_value |= UART_LCR_PARITY;
216 		else
217 			urb_value |= SERIAL_EVEN_PARITY;
218 	}
219 
220 	switch (cflag & CSIZE) {
221 	case CS5:
222 		urb_value |= UART_LCR_WLEN5;
223 		break;
224 	case CS6:
225 		urb_value |= UART_LCR_WLEN6;
226 		break;
227 	case CS7:
228 		urb_value |= UART_LCR_WLEN7;
229 		break;
230 	default:
231 	case CS8:
232 		urb_value |= UART_LCR_WLEN8;
233 		break;
234 	}
235 
236 	baud = tty_get_baud_rate(tty);
237 	if (!baud)
238 		baud = 9600;
239 
240 	dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud);
241 
242 
243 	divisor = MAX_BAUD_RATE / baud;
244 	remainder = MAX_BAUD_RATE % baud;
245 	if (((remainder * 2) >= baud) && (baud != 110))
246 		divisor++;
247 
248 	urb_value = urb_value << 8;
249 
250 	result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
251 	if (result < 0)
252 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
253 
254 	if (cflag & CRTSCTS)
255 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
256 					    SERIAL_CRTSCTS, 0);
257 	else
258 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
259 					    0, 0);
260 	if (result < 0)
261 		dev_dbg(&port->dev, "%s - set HW flow control failed\n", __func__);
262 
263 	if (I_IXOFF(tty) || I_IXON(tty)) {
264 		u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty)));
265 
266 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
267 					    x, 0);
268 	} else
269 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
270 					    0, 0);
271 
272 	if (result < 0)
273 		dev_dbg(&port->dev, "%s - set SW flow control failed\n", __func__);
274 
275 }
276 
277 
278 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port)
279 {
280 	struct usb_device *dev = port->serial->dev;
281 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
282 	u8 *data;
283 	int result;
284 	unsigned long flags;
285 
286 	data = kzalloc(2, GFP_KERNEL);
287 	if (!data)
288 		return -ENOMEM;
289 
290 	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
291 				 QT_OPEN_CLOSE_CHANNEL,
292 				 QT_TRANSFER_IN, 0x01,
293 				 0, data, 2, 300);
294 	if (result < 0) {
295 		dev_dbg(&port->dev, "%s - open failed %i\n", __func__, result);
296 		kfree(data);
297 		return result;
298 	}
299 
300 	spin_lock_irqsave(&priv->status_lock, flags);
301 	priv->shadowLSR = data[0];
302 	priv->shadowMSR = data[1];
303 	spin_unlock_irqrestore(&priv->status_lock, flags);
304 
305 	kfree(data);
306 
307 /* set to 9600 */
308 	result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
309 	if (result < 0)
310 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
311 
312 	if (tty)
313 		ssu100_set_termios(tty, port, &tty->termios);
314 
315 	return usb_serial_generic_open(tty, port);
316 }
317 
318 static void ssu100_close(struct usb_serial_port *port)
319 {
320 	usb_serial_generic_close(port);
321 }
322 
323 static int get_serial_info(struct usb_serial_port *port,
324 			   struct serial_struct __user *retinfo)
325 {
326 	struct serial_struct tmp;
327 
328 	if (!retinfo)
329 		return -EFAULT;
330 
331 	memset(&tmp, 0, sizeof(tmp));
332 	tmp.line		= port->serial->minor;
333 	tmp.port		= 0;
334 	tmp.irq			= 0;
335 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
336 	tmp.xmit_fifo_size	= port->bulk_out_size;
337 	tmp.baud_base		= 9600;
338 	tmp.close_delay		= 5*HZ;
339 	tmp.closing_wait	= 30*HZ;
340 
341 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
342 		return -EFAULT;
343 	return 0;
344 }
345 
346 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
347 {
348 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
349 	struct async_icount prev, cur;
350 	unsigned long flags;
351 
352 	spin_lock_irqsave(&priv->status_lock, flags);
353 	prev = priv->icount;
354 	spin_unlock_irqrestore(&priv->status_lock, flags);
355 
356 	while (1) {
357 		wait_event_interruptible(port->delta_msr_wait,
358 					 (port->serial->disconnected ||
359 					  (priv->icount.rng != prev.rng) ||
360 					  (priv->icount.dsr != prev.dsr) ||
361 					  (priv->icount.dcd != prev.dcd) ||
362 					  (priv->icount.cts != prev.cts)));
363 
364 		if (signal_pending(current))
365 			return -ERESTARTSYS;
366 
367 		if (port->serial->disconnected)
368 			return -EIO;
369 
370 		spin_lock_irqsave(&priv->status_lock, flags);
371 		cur = priv->icount;
372 		spin_unlock_irqrestore(&priv->status_lock, flags);
373 
374 		if ((prev.rng == cur.rng) &&
375 		    (prev.dsr == cur.dsr) &&
376 		    (prev.dcd == cur.dcd) &&
377 		    (prev.cts == cur.cts))
378 			return -EIO;
379 
380 		if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) ||
381 		    (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) ||
382 		    (arg & TIOCM_CD  && (prev.dcd != cur.dcd)) ||
383 		    (arg & TIOCM_CTS && (prev.cts != cur.cts)))
384 			return 0;
385 	}
386 	return 0;
387 }
388 
389 static int ssu100_get_icount(struct tty_struct *tty,
390 			struct serial_icounter_struct *icount)
391 {
392 	struct usb_serial_port *port = tty->driver_data;
393 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
394 	struct async_icount cnow = priv->icount;
395 
396 	icount->cts = cnow.cts;
397 	icount->dsr = cnow.dsr;
398 	icount->rng = cnow.rng;
399 	icount->dcd = cnow.dcd;
400 	icount->rx = cnow.rx;
401 	icount->tx = cnow.tx;
402 	icount->frame = cnow.frame;
403 	icount->overrun = cnow.overrun;
404 	icount->parity = cnow.parity;
405 	icount->brk = cnow.brk;
406 	icount->buf_overrun = cnow.buf_overrun;
407 
408 	return 0;
409 }
410 
411 
412 
413 static int ssu100_ioctl(struct tty_struct *tty,
414 		    unsigned int cmd, unsigned long arg)
415 {
416 	struct usb_serial_port *port = tty->driver_data;
417 
418 	dev_dbg(&port->dev, "%s cmd 0x%04x\n", __func__, cmd);
419 
420 	switch (cmd) {
421 	case TIOCGSERIAL:
422 		return get_serial_info(port,
423 				       (struct serial_struct __user *) arg);
424 
425 	case TIOCMIWAIT:
426 		return wait_modem_info(port, arg);
427 
428 	default:
429 		break;
430 	}
431 
432 	dev_dbg(&port->dev, "%s arg not supported\n", __func__);
433 
434 	return -ENOIOCTLCMD;
435 }
436 
437 static int ssu100_attach(struct usb_serial *serial)
438 {
439 	return ssu100_initdevice(serial->dev);
440 }
441 
442 static int ssu100_port_probe(struct usb_serial_port *port)
443 {
444 	struct ssu100_port_private *priv;
445 
446 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
447 	if (!priv)
448 		return -ENOMEM;
449 
450 	spin_lock_init(&priv->status_lock);
451 
452 	usb_set_serial_port_data(port, priv);
453 
454 	return 0;
455 }
456 
457 static int ssu100_port_remove(struct usb_serial_port *port)
458 {
459 	struct ssu100_port_private *priv;
460 
461 	priv = usb_get_serial_port_data(port);
462 	kfree(priv);
463 
464 	return 0;
465 }
466 
467 static int ssu100_tiocmget(struct tty_struct *tty)
468 {
469 	struct usb_serial_port *port = tty->driver_data;
470 	struct usb_device *dev = port->serial->dev;
471 	u8 *d;
472 	int r;
473 
474 	d = kzalloc(2, GFP_KERNEL);
475 	if (!d)
476 		return -ENOMEM;
477 
478 	r = ssu100_getregister(dev, 0, UART_MCR, d);
479 	if (r < 0)
480 		goto mget_out;
481 
482 	r = ssu100_getregister(dev, 0, UART_MSR, d+1);
483 	if (r < 0)
484 		goto mget_out;
485 
486 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
487 		(d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
488 		(d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
489 		(d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
490 		(d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
491 		(d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
492 
493 mget_out:
494 	kfree(d);
495 	return r;
496 }
497 
498 static int ssu100_tiocmset(struct tty_struct *tty,
499 			   unsigned int set, unsigned int clear)
500 {
501 	struct usb_serial_port *port = tty->driver_data;
502 	struct usb_device *dev = port->serial->dev;
503 
504 	return update_mctrl(dev, set, clear);
505 }
506 
507 static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
508 {
509 	struct usb_device *dev = port->serial->dev;
510 
511 	/* Disable flow control */
512 	if (!on) {
513 		if (ssu100_setregister(dev, 0, UART_MCR, 0) < 0)
514 			dev_err(&port->dev, "error from flowcontrol urb\n");
515 	}
516 	/* drop RTS and DTR */
517 	if (on)
518 		set_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
519 	else
520 		clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
521 }
522 
523 static void ssu100_update_msr(struct usb_serial_port *port, u8 msr)
524 {
525 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
526 	unsigned long flags;
527 
528 	spin_lock_irqsave(&priv->status_lock, flags);
529 	priv->shadowMSR = msr;
530 	spin_unlock_irqrestore(&priv->status_lock, flags);
531 
532 	if (msr & UART_MSR_ANY_DELTA) {
533 		/* update input line counters */
534 		if (msr & UART_MSR_DCTS)
535 			priv->icount.cts++;
536 		if (msr & UART_MSR_DDSR)
537 			priv->icount.dsr++;
538 		if (msr & UART_MSR_DDCD)
539 			priv->icount.dcd++;
540 		if (msr & UART_MSR_TERI)
541 			priv->icount.rng++;
542 		wake_up_interruptible(&port->delta_msr_wait);
543 	}
544 }
545 
546 static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr,
547 			      char *tty_flag)
548 {
549 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
550 	unsigned long flags;
551 
552 	spin_lock_irqsave(&priv->status_lock, flags);
553 	priv->shadowLSR = lsr;
554 	spin_unlock_irqrestore(&priv->status_lock, flags);
555 
556 	*tty_flag = TTY_NORMAL;
557 	if (lsr & UART_LSR_BRK_ERROR_BITS) {
558 		/* we always want to update icount, but we only want to
559 		 * update tty_flag for one case */
560 		if (lsr & UART_LSR_BI) {
561 			priv->icount.brk++;
562 			*tty_flag = TTY_BREAK;
563 			usb_serial_handle_break(port);
564 		}
565 		if (lsr & UART_LSR_PE) {
566 			priv->icount.parity++;
567 			if (*tty_flag == TTY_NORMAL)
568 				*tty_flag = TTY_PARITY;
569 		}
570 		if (lsr & UART_LSR_FE) {
571 			priv->icount.frame++;
572 			if (*tty_flag == TTY_NORMAL)
573 				*tty_flag = TTY_FRAME;
574 		}
575 		if (lsr & UART_LSR_OE){
576 			priv->icount.overrun++;
577 			if (*tty_flag == TTY_NORMAL)
578 				*tty_flag = TTY_OVERRUN;
579 		}
580 	}
581 
582 }
583 
584 static void ssu100_process_read_urb(struct urb *urb)
585 {
586 	struct usb_serial_port *port = urb->context;
587 	char *packet = (char *)urb->transfer_buffer;
588 	char flag = TTY_NORMAL;
589 	u32 len = urb->actual_length;
590 	int i;
591 	char *ch;
592 
593 	if ((len >= 4) &&
594 	    (packet[0] == 0x1b) && (packet[1] == 0x1b) &&
595 	    ((packet[2] == 0x00) || (packet[2] == 0x01))) {
596 		if (packet[2] == 0x00) {
597 			ssu100_update_lsr(port, packet[3], &flag);
598 			if (flag == TTY_OVERRUN)
599 				tty_insert_flip_char(&port->port, 0,
600 						TTY_OVERRUN);
601 		}
602 		if (packet[2] == 0x01)
603 			ssu100_update_msr(port, packet[3]);
604 
605 		len -= 4;
606 		ch = packet + 4;
607 	} else
608 		ch = packet;
609 
610 	if (!len)
611 		return;	/* status only */
612 
613 	if (port->port.console && port->sysrq) {
614 		for (i = 0; i < len; i++, ch++) {
615 			if (!usb_serial_handle_sysrq_char(port, *ch))
616 				tty_insert_flip_char(&port->port, *ch, flag);
617 		}
618 	} else
619 		tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);
620 
621 	tty_flip_buffer_push(&port->port);
622 }
623 
624 static struct usb_serial_driver ssu100_device = {
625 	.driver = {
626 		.owner = THIS_MODULE,
627 		.name = "ssu100",
628 	},
629 	.description	     = DRIVER_DESC,
630 	.id_table	     = id_table,
631 	.num_ports	     = 1,
632 	.open		     = ssu100_open,
633 	.close		     = ssu100_close,
634 	.attach              = ssu100_attach,
635 	.port_probe          = ssu100_port_probe,
636 	.port_remove         = ssu100_port_remove,
637 	.dtr_rts             = ssu100_dtr_rts,
638 	.process_read_urb    = ssu100_process_read_urb,
639 	.tiocmget            = ssu100_tiocmget,
640 	.tiocmset            = ssu100_tiocmset,
641 	.get_icount	     = ssu100_get_icount,
642 	.ioctl               = ssu100_ioctl,
643 	.set_termios         = ssu100_set_termios,
644 	.disconnect          = usb_serial_generic_disconnect,
645 };
646 
647 static struct usb_serial_driver * const serial_drivers[] = {
648 	&ssu100_device, NULL
649 };
650 
651 module_usb_serial_driver(serial_drivers, id_table);
652 
653 MODULE_DESCRIPTION(DRIVER_DESC);
654 MODULE_LICENSE("GPL");
655