xref: /openbmc/linux/drivers/usb/serial/ssu100.c (revision 8a26af30)
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/slab.h>
10 #include <linux/tty.h>
11 #include <linux/tty_driver.h>
12 #include <linux/tty_flip.h>
13 #include <linux/module.h>
14 #include <linux/serial.h>
15 #include <linux/usb.h>
16 #include <linux/usb/serial.h>
17 #include <linux/serial_reg.h>
18 #include <linux/uaccess.h>
19 
20 #define QT_OPEN_CLOSE_CHANNEL       0xca
21 #define QT_SET_GET_DEVICE           0xc2
22 #define QT_SET_GET_REGISTER         0xc0
23 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
24 #define QT_SET_ATF                  0xcd
25 #define QT_GET_SET_UART             0xc1
26 #define QT_TRANSFER_IN              0xc0
27 #define QT_HW_FLOW_CONTROL_MASK     0xc5
28 #define QT_SW_FLOW_CONTROL_MASK     0xc6
29 
30 #define  SERIAL_MSR_MASK            0xf0
31 
32 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
33 
34 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
35 
36 #define  MAX_BAUD_RATE              460800
37 
38 #define ATC_DISABLED                0x00
39 #define DUPMODE_BITS        0xc0
40 #define RR_BITS             0x03
41 #define LOOPMODE_BITS       0x41
42 #define RS232_MODE          0x00
43 #define RTSCTS_TO_CONNECTOR 0x40
44 #define CLKS_X4             0x02
45 #define FULLPWRBIT          0x00000080
46 #define NEXT_BOARD_POWER_BIT        0x00000004
47 
48 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"
49 
50 #define	USB_VENDOR_ID_QUATECH	0x061d	/* Quatech VID */
51 #define QUATECH_SSU100	0xC020	/* SSU100 */
52 
53 static const struct usb_device_id id_table[] = {
54 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
55 	{}			/* Terminating entry */
56 };
57 MODULE_DEVICE_TABLE(usb, id_table);
58 
59 struct ssu100_port_private {
60 	spinlock_t status_lock;
61 	u8 shadowLSR;
62 	u8 shadowMSR;
63 };
64 
65 static inline int ssu100_control_msg(struct usb_device *dev,
66 				     u8 request, u16 data, u16 index)
67 {
68 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
69 			       request, 0x40, data, index,
70 			       NULL, 0, 300);
71 }
72 
73 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data)
74 {
75 	u16 x = ((u16)(data[1] << 8) | (u16)(data[0]));
76 
77 	return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
78 }
79 
80 
81 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data)
82 {
83 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
84 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
85 			       data, 3, 300);
86 }
87 
88 static inline int ssu100_getregister(struct usb_device *dev,
89 				     unsigned short uart,
90 				     unsigned short reg,
91 				     u8 *data)
92 {
93 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
94 			       QT_SET_GET_REGISTER, 0xc0, reg,
95 			       uart, data, sizeof(*data), 300);
96 
97 }
98 
99 
100 static inline int ssu100_setregister(struct usb_device *dev,
101 				     unsigned short uart,
102 				     unsigned short reg,
103 				     u16 data)
104 {
105 	u16 value = (data << 8) | reg;
106 
107 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
108 			       QT_SET_GET_REGISTER, 0x40, value, uart,
109 			       NULL, 0, 300);
110 
111 }
112 
113 #define set_mctrl(dev, set)		update_mctrl((dev), (set), 0)
114 #define clear_mctrl(dev, clear)	update_mctrl((dev), 0, (clear))
115 
116 /* these do not deal with device that have more than 1 port */
117 static inline int update_mctrl(struct usb_device *dev, unsigned int set,
118 			       unsigned int clear)
119 {
120 	unsigned urb_value;
121 	int result;
122 
123 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
124 		dev_dbg(&dev->dev, "%s - DTR|RTS not being set|cleared\n", __func__);
125 		return 0;	/* no change */
126 	}
127 
128 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
129 	urb_value = 0;
130 	if (set & TIOCM_DTR)
131 		urb_value |= UART_MCR_DTR;
132 	if (set & TIOCM_RTS)
133 		urb_value |= UART_MCR_RTS;
134 
135 	result = ssu100_setregister(dev, 0, UART_MCR, urb_value);
136 	if (result < 0)
137 		dev_dbg(&dev->dev, "%s Error from MODEM_CTRL urb\n", __func__);
138 
139 	return result;
140 }
141 
142 static int ssu100_initdevice(struct usb_device *dev)
143 {
144 	u8 *data;
145 	int result = 0;
146 
147 	data = kzalloc(3, GFP_KERNEL);
148 	if (!data)
149 		return -ENOMEM;
150 
151 	result = ssu100_getdevice(dev, data);
152 	if (result < 0) {
153 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
154 		goto out;
155 	}
156 
157 	data[1] &= ~FULLPWRBIT;
158 
159 	result = ssu100_setdevice(dev, data);
160 	if (result < 0) {
161 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
162 		goto out;
163 	}
164 
165 	result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
166 	if (result < 0) {
167 		dev_dbg(&dev->dev, "%s - set prebuffer level failed %i\n", __func__, result);
168 		goto out;
169 	}
170 
171 	result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
172 	if (result < 0) {
173 		dev_dbg(&dev->dev, "%s - set ATFprebuffer level failed %i\n", __func__, result);
174 		goto out;
175 	}
176 
177 	result = ssu100_getdevice(dev, data);
178 	if (result < 0) {
179 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
180 		goto out;
181 	}
182 
183 	data[0] &= ~(RR_BITS | DUPMODE_BITS);
184 	data[0] |= CLKS_X4;
185 	data[1] &= ~(LOOPMODE_BITS);
186 	data[1] |= RS232_MODE;
187 
188 	result = ssu100_setdevice(dev, data);
189 	if (result < 0) {
190 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
191 		goto out;
192 	}
193 
194 out:	kfree(data);
195 	return result;
196 
197 }
198 
199 
200 static void ssu100_set_termios(struct tty_struct *tty,
201 			       struct usb_serial_port *port,
202 			       struct ktermios *old_termios)
203 {
204 	struct usb_device *dev = port->serial->dev;
205 	struct ktermios *termios = &tty->termios;
206 	u16 baud, divisor, remainder;
207 	unsigned int cflag = termios->c_cflag;
208 	u16 urb_value = 0; /* will hold the new flags */
209 	int result;
210 
211 	if (cflag & PARENB) {
212 		if (cflag & PARODD)
213 			urb_value |= UART_LCR_PARITY;
214 		else
215 			urb_value |= SERIAL_EVEN_PARITY;
216 	}
217 
218 	switch (cflag & CSIZE) {
219 	case CS5:
220 		urb_value |= UART_LCR_WLEN5;
221 		break;
222 	case CS6:
223 		urb_value |= UART_LCR_WLEN6;
224 		break;
225 	case CS7:
226 		urb_value |= UART_LCR_WLEN7;
227 		break;
228 	default:
229 	case CS8:
230 		urb_value |= UART_LCR_WLEN8;
231 		break;
232 	}
233 
234 	baud = tty_get_baud_rate(tty);
235 	if (!baud)
236 		baud = 9600;
237 
238 	dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud);
239 
240 
241 	divisor = MAX_BAUD_RATE / baud;
242 	remainder = MAX_BAUD_RATE % baud;
243 	if (((remainder * 2) >= baud) && (baud != 110))
244 		divisor++;
245 
246 	urb_value = urb_value << 8;
247 
248 	result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
249 	if (result < 0)
250 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
251 
252 	if (cflag & CRTSCTS)
253 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
254 					    SERIAL_CRTSCTS, 0);
255 	else
256 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
257 					    0, 0);
258 	if (result < 0)
259 		dev_dbg(&port->dev, "%s - set HW flow control failed\n", __func__);
260 
261 	if (I_IXOFF(tty) || I_IXON(tty)) {
262 		u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty)));
263 
264 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
265 					    x, 0);
266 	} else
267 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
268 					    0, 0);
269 
270 	if (result < 0)
271 		dev_dbg(&port->dev, "%s - set SW flow control failed\n", __func__);
272 
273 }
274 
275 
276 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port)
277 {
278 	struct usb_device *dev = port->serial->dev;
279 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
280 	u8 *data;
281 	int result;
282 	unsigned long flags;
283 
284 	data = kzalloc(2, GFP_KERNEL);
285 	if (!data)
286 		return -ENOMEM;
287 
288 	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
289 				 QT_OPEN_CLOSE_CHANNEL,
290 				 QT_TRANSFER_IN, 0x01,
291 				 0, data, 2, 300);
292 	if (result < 0) {
293 		dev_dbg(&port->dev, "%s - open failed %i\n", __func__, result);
294 		kfree(data);
295 		return result;
296 	}
297 
298 	spin_lock_irqsave(&priv->status_lock, flags);
299 	priv->shadowLSR = data[0];
300 	priv->shadowMSR = data[1];
301 	spin_unlock_irqrestore(&priv->status_lock, flags);
302 
303 	kfree(data);
304 
305 /* set to 9600 */
306 	result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
307 	if (result < 0)
308 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
309 
310 	if (tty)
311 		ssu100_set_termios(tty, port, &tty->termios);
312 
313 	return usb_serial_generic_open(tty, port);
314 }
315 
316 static int get_serial_info(struct usb_serial_port *port,
317 			   struct serial_struct __user *retinfo)
318 {
319 	struct serial_struct tmp;
320 
321 	if (!retinfo)
322 		return -EFAULT;
323 
324 	memset(&tmp, 0, sizeof(tmp));
325 	tmp.line		= port->minor;
326 	tmp.port		= 0;
327 	tmp.irq			= 0;
328 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
329 	tmp.xmit_fifo_size	= port->bulk_out_size;
330 	tmp.baud_base		= 9600;
331 	tmp.close_delay		= 5*HZ;
332 	tmp.closing_wait	= 30*HZ;
333 
334 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
335 		return -EFAULT;
336 	return 0;
337 }
338 
339 static int ssu100_ioctl(struct tty_struct *tty,
340 		    unsigned int cmd, unsigned long arg)
341 {
342 	struct usb_serial_port *port = tty->driver_data;
343 
344 	switch (cmd) {
345 	case TIOCGSERIAL:
346 		return get_serial_info(port,
347 				       (struct serial_struct __user *) arg);
348 	default:
349 		break;
350 	}
351 
352 	return -ENOIOCTLCMD;
353 }
354 
355 static int ssu100_attach(struct usb_serial *serial)
356 {
357 	return ssu100_initdevice(serial->dev);
358 }
359 
360 static int ssu100_port_probe(struct usb_serial_port *port)
361 {
362 	struct ssu100_port_private *priv;
363 
364 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
365 	if (!priv)
366 		return -ENOMEM;
367 
368 	spin_lock_init(&priv->status_lock);
369 
370 	usb_set_serial_port_data(port, priv);
371 
372 	return 0;
373 }
374 
375 static int ssu100_port_remove(struct usb_serial_port *port)
376 {
377 	struct ssu100_port_private *priv;
378 
379 	priv = usb_get_serial_port_data(port);
380 	kfree(priv);
381 
382 	return 0;
383 }
384 
385 static int ssu100_tiocmget(struct tty_struct *tty)
386 {
387 	struct usb_serial_port *port = tty->driver_data;
388 	struct usb_device *dev = port->serial->dev;
389 	u8 *d;
390 	int r;
391 
392 	d = kzalloc(2, GFP_KERNEL);
393 	if (!d)
394 		return -ENOMEM;
395 
396 	r = ssu100_getregister(dev, 0, UART_MCR, d);
397 	if (r < 0)
398 		goto mget_out;
399 
400 	r = ssu100_getregister(dev, 0, UART_MSR, d+1);
401 	if (r < 0)
402 		goto mget_out;
403 
404 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
405 		(d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
406 		(d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
407 		(d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
408 		(d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
409 		(d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
410 
411 mget_out:
412 	kfree(d);
413 	return r;
414 }
415 
416 static int ssu100_tiocmset(struct tty_struct *tty,
417 			   unsigned int set, unsigned int clear)
418 {
419 	struct usb_serial_port *port = tty->driver_data;
420 	struct usb_device *dev = port->serial->dev;
421 
422 	return update_mctrl(dev, set, clear);
423 }
424 
425 static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
426 {
427 	struct usb_device *dev = port->serial->dev;
428 
429 	/* Disable flow control */
430 	if (!on) {
431 		if (ssu100_setregister(dev, 0, UART_MCR, 0) < 0)
432 			dev_err(&port->dev, "error from flowcontrol urb\n");
433 	}
434 	/* drop RTS and DTR */
435 	if (on)
436 		set_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
437 	else
438 		clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
439 }
440 
441 static void ssu100_update_msr(struct usb_serial_port *port, u8 msr)
442 {
443 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
444 	unsigned long flags;
445 
446 	spin_lock_irqsave(&priv->status_lock, flags);
447 	priv->shadowMSR = msr;
448 	spin_unlock_irqrestore(&priv->status_lock, flags);
449 
450 	if (msr & UART_MSR_ANY_DELTA) {
451 		/* update input line counters */
452 		if (msr & UART_MSR_DCTS)
453 			port->icount.cts++;
454 		if (msr & UART_MSR_DDSR)
455 			port->icount.dsr++;
456 		if (msr & UART_MSR_DDCD)
457 			port->icount.dcd++;
458 		if (msr & UART_MSR_TERI)
459 			port->icount.rng++;
460 		wake_up_interruptible(&port->port.delta_msr_wait);
461 	}
462 }
463 
464 static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr,
465 			      char *tty_flag)
466 {
467 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
468 	unsigned long flags;
469 
470 	spin_lock_irqsave(&priv->status_lock, flags);
471 	priv->shadowLSR = lsr;
472 	spin_unlock_irqrestore(&priv->status_lock, flags);
473 
474 	*tty_flag = TTY_NORMAL;
475 	if (lsr & UART_LSR_BRK_ERROR_BITS) {
476 		/* we always want to update icount, but we only want to
477 		 * update tty_flag for one case */
478 		if (lsr & UART_LSR_BI) {
479 			port->icount.brk++;
480 			*tty_flag = TTY_BREAK;
481 			usb_serial_handle_break(port);
482 		}
483 		if (lsr & UART_LSR_PE) {
484 			port->icount.parity++;
485 			if (*tty_flag == TTY_NORMAL)
486 				*tty_flag = TTY_PARITY;
487 		}
488 		if (lsr & UART_LSR_FE) {
489 			port->icount.frame++;
490 			if (*tty_flag == TTY_NORMAL)
491 				*tty_flag = TTY_FRAME;
492 		}
493 		if (lsr & UART_LSR_OE){
494 			port->icount.overrun++;
495 			if (*tty_flag == TTY_NORMAL)
496 				*tty_flag = TTY_OVERRUN;
497 		}
498 	}
499 
500 }
501 
502 static void ssu100_process_read_urb(struct urb *urb)
503 {
504 	struct usb_serial_port *port = urb->context;
505 	char *packet = (char *)urb->transfer_buffer;
506 	char flag = TTY_NORMAL;
507 	u32 len = urb->actual_length;
508 	int i;
509 	char *ch;
510 
511 	if ((len >= 4) &&
512 	    (packet[0] == 0x1b) && (packet[1] == 0x1b) &&
513 	    ((packet[2] == 0x00) || (packet[2] == 0x01))) {
514 		if (packet[2] == 0x00) {
515 			ssu100_update_lsr(port, packet[3], &flag);
516 			if (flag == TTY_OVERRUN)
517 				tty_insert_flip_char(&port->port, 0,
518 						TTY_OVERRUN);
519 		}
520 		if (packet[2] == 0x01)
521 			ssu100_update_msr(port, packet[3]);
522 
523 		len -= 4;
524 		ch = packet + 4;
525 	} else
526 		ch = packet;
527 
528 	if (!len)
529 		return;	/* status only */
530 
531 	if (port->port.console && port->sysrq) {
532 		for (i = 0; i < len; i++, ch++) {
533 			if (!usb_serial_handle_sysrq_char(port, *ch))
534 				tty_insert_flip_char(&port->port, *ch, flag);
535 		}
536 	} else
537 		tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);
538 
539 	tty_flip_buffer_push(&port->port);
540 }
541 
542 static struct usb_serial_driver ssu100_device = {
543 	.driver = {
544 		.owner = THIS_MODULE,
545 		.name = "ssu100",
546 	},
547 	.description	     = DRIVER_DESC,
548 	.id_table	     = id_table,
549 	.num_ports	     = 1,
550 	.open		     = ssu100_open,
551 	.attach              = ssu100_attach,
552 	.port_probe          = ssu100_port_probe,
553 	.port_remove         = ssu100_port_remove,
554 	.dtr_rts             = ssu100_dtr_rts,
555 	.process_read_urb    = ssu100_process_read_urb,
556 	.tiocmget            = ssu100_tiocmget,
557 	.tiocmset            = ssu100_tiocmset,
558 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
559 	.get_icount	     = usb_serial_generic_get_icount,
560 	.ioctl               = ssu100_ioctl,
561 	.set_termios         = ssu100_set_termios,
562 };
563 
564 static struct usb_serial_driver * const serial_drivers[] = {
565 	&ssu100_device, NULL
566 };
567 
568 module_usb_serial_driver(serial_drivers, id_table);
569 
570 MODULE_DESCRIPTION(DRIVER_DESC);
571 MODULE_LICENSE("GPL");
572