xref: /linux/drivers/usb/serial/belkin_sa.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Belkin USB Serial Adapter Driver
3  *
4  *  Copyright (C) 2000		William Greathouse (wgreathouse@smva.com)
5  *  Copyright (C) 2000-2001 	Greg Kroah-Hartman (greg@kroah.com)
6  *  Copyright (C) 2010		Johan Hovold (jhovold@gmail.com)
7  *
8  *  This program is largely derived from work by the linux-usb group
9  *  and associated source files.  Please see the usb/serial files for
10  *  individual credits and copyrights.
11  *
12  * 	This program is free software; you can redistribute it and/or modify
13  * 	it under the terms of the GNU General Public License as published by
14  * 	the Free Software Foundation; either version 2 of the License, or
15  * 	(at your option) any later version.
16  *
17  * See Documentation/usb/usb-serial.txt for more information on using this
18  * driver
19  *
20  * TODO:
21  * -- Add true modem contol line query capability.  Currently we track the
22  *    states reported by the interrupt and the states we request.
23  * -- Add support for flush commands
24  */
25 
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/tty.h>
31 #include <linux/tty_driver.h>
32 #include <linux/tty_flip.h>
33 #include <linux/module.h>
34 #include <linux/spinlock.h>
35 #include <linux/uaccess.h>
36 #include <linux/usb.h>
37 #include <linux/usb/serial.h>
38 #include "belkin_sa.h"
39 
40 static bool debug;
41 
42 /*
43  * Version Information
44  */
45 #define DRIVER_VERSION "v1.3"
46 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
47 #define DRIVER_DESC "USB Belkin Serial converter driver"
48 
49 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
50 static int  belkin_sa_startup(struct usb_serial *serial);
51 static void belkin_sa_release(struct usb_serial *serial);
52 static int  belkin_sa_open(struct tty_struct *tty,
53 			struct usb_serial_port *port);
54 static void belkin_sa_close(struct usb_serial_port *port);
55 static void belkin_sa_read_int_callback(struct urb *urb);
56 static void belkin_sa_process_read_urb(struct urb *urb);
57 static void belkin_sa_set_termios(struct tty_struct *tty,
58 			struct usb_serial_port *port, struct ktermios * old);
59 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
60 static int  belkin_sa_tiocmget(struct tty_struct *tty);
61 static int  belkin_sa_tiocmset(struct tty_struct *tty,
62 					unsigned int set, unsigned int clear);
63 
64 
65 static const struct usb_device_id id_table_combined[] = {
66 	{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
67 	{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
68 	{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
69 	{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
70 	{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
71 	{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
72 	{ }	/* Terminating entry */
73 };
74 MODULE_DEVICE_TABLE(usb, id_table_combined);
75 
76 static struct usb_driver belkin_driver = {
77 	.name =		"belkin",
78 	.probe =	usb_serial_probe,
79 	.disconnect =	usb_serial_disconnect,
80 	.id_table =	id_table_combined,
81 	.no_dynamic_id =	1,
82 };
83 
84 /* All of the device info needed for the serial converters */
85 static struct usb_serial_driver belkin_device = {
86 	.driver = {
87 		.owner =	THIS_MODULE,
88 		.name =		"belkin",
89 	},
90 	.description =		"Belkin / Peracom / GoHubs USB Serial Adapter",
91 	.usb_driver =		&belkin_driver,
92 	.id_table =		id_table_combined,
93 	.num_ports =		1,
94 	.open =			belkin_sa_open,
95 	.close =		belkin_sa_close,
96 	.read_int_callback =	belkin_sa_read_int_callback,
97 	.process_read_urb =	belkin_sa_process_read_urb,
98 	.set_termios =		belkin_sa_set_termios,
99 	.break_ctl =		belkin_sa_break_ctl,
100 	.tiocmget =		belkin_sa_tiocmget,
101 	.tiocmset =		belkin_sa_tiocmset,
102 	.attach =		belkin_sa_startup,
103 	.release =		belkin_sa_release,
104 };
105 
106 struct belkin_sa_private {
107 	spinlock_t		lock;
108 	unsigned long		control_state;
109 	unsigned char		last_lsr;
110 	unsigned char		last_msr;
111 	int			bad_flow_control;
112 };
113 
114 
115 /*
116  * ***************************************************************************
117  * Belkin USB Serial Adapter F5U103 specific driver functions
118  * ***************************************************************************
119  */
120 
121 #define WDR_TIMEOUT 5000 /* default urb timeout */
122 
123 /* assumes that struct usb_serial *serial is available */
124 #define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
125 					    (c), BELKIN_SA_SET_REQUEST_TYPE, \
126 					    (v), 0, NULL, 0, WDR_TIMEOUT)
127 
128 /* do some startup allocations not currently performed by usb_serial_probe() */
129 static int belkin_sa_startup(struct usb_serial *serial)
130 {
131 	struct usb_device *dev = serial->dev;
132 	struct belkin_sa_private *priv;
133 
134 	/* allocate the private data structure */
135 	priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
136 	if (!priv)
137 		return -1; /* error */
138 	/* set initial values for control structures */
139 	spin_lock_init(&priv->lock);
140 	priv->control_state = 0;
141 	priv->last_lsr = 0;
142 	priv->last_msr = 0;
143 	/* see comments at top of file */
144 	priv->bad_flow_control =
145 		(le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
146 	dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
147 					le16_to_cpu(dev->descriptor.bcdDevice),
148 					priv->bad_flow_control);
149 
150 	init_waitqueue_head(&serial->port[0]->write_wait);
151 	usb_set_serial_port_data(serial->port[0], priv);
152 
153 	return 0;
154 }
155 
156 static void belkin_sa_release(struct usb_serial *serial)
157 {
158 	int i;
159 
160 	dbg("%s", __func__);
161 
162 	for (i = 0; i < serial->num_ports; ++i)
163 		kfree(usb_get_serial_port_data(serial->port[i]));
164 }
165 
166 static int belkin_sa_open(struct tty_struct *tty,
167 					struct usb_serial_port *port)
168 {
169 	int retval;
170 
171 	dbg("%s port %d", __func__, port->number);
172 
173 	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
174 	if (retval) {
175 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
176 		return retval;
177 	}
178 
179 	retval = usb_serial_generic_open(tty, port);
180 	if (retval)
181 		usb_kill_urb(port->interrupt_in_urb);
182 
183 	return retval;
184 }
185 
186 static void belkin_sa_close(struct usb_serial_port *port)
187 {
188 	dbg("%s port %d", __func__, port->number);
189 
190 	usb_serial_generic_close(port);
191 	usb_kill_urb(port->interrupt_in_urb);
192 }
193 
194 static void belkin_sa_read_int_callback(struct urb *urb)
195 {
196 	struct usb_serial_port *port = urb->context;
197 	struct belkin_sa_private *priv;
198 	unsigned char *data = urb->transfer_buffer;
199 	int retval;
200 	int status = urb->status;
201 	unsigned long flags;
202 
203 	switch (status) {
204 	case 0:
205 		/* success */
206 		break;
207 	case -ECONNRESET:
208 	case -ENOENT:
209 	case -ESHUTDOWN:
210 		/* this urb is terminated, clean up */
211 		dbg("%s - urb shutting down with status: %d",
212 		    __func__, status);
213 		return;
214 	default:
215 		dbg("%s - nonzero urb status received: %d",
216 		    __func__, status);
217 		goto exit;
218 	}
219 
220 	usb_serial_debug_data(debug, &port->dev, __func__,
221 					urb->actual_length, data);
222 
223 	/* Handle known interrupt data */
224 	/* ignore data[0] and data[1] */
225 
226 	priv = usb_get_serial_port_data(port);
227 	spin_lock_irqsave(&priv->lock, flags);
228 	priv->last_msr = data[BELKIN_SA_MSR_INDEX];
229 
230 	/* Record Control Line states */
231 	if (priv->last_msr & BELKIN_SA_MSR_DSR)
232 		priv->control_state |= TIOCM_DSR;
233 	else
234 		priv->control_state &= ~TIOCM_DSR;
235 
236 	if (priv->last_msr & BELKIN_SA_MSR_CTS)
237 		priv->control_state |= TIOCM_CTS;
238 	else
239 		priv->control_state &= ~TIOCM_CTS;
240 
241 	if (priv->last_msr & BELKIN_SA_MSR_RI)
242 		priv->control_state |= TIOCM_RI;
243 	else
244 		priv->control_state &= ~TIOCM_RI;
245 
246 	if (priv->last_msr & BELKIN_SA_MSR_CD)
247 		priv->control_state |= TIOCM_CD;
248 	else
249 		priv->control_state &= ~TIOCM_CD;
250 
251 	priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
252 	spin_unlock_irqrestore(&priv->lock, flags);
253 exit:
254 	retval = usb_submit_urb(urb, GFP_ATOMIC);
255 	if (retval)
256 		dev_err(&port->dev, "%s - usb_submit_urb failed with "
257 			"result %d\n", __func__, retval);
258 }
259 
260 static void belkin_sa_process_read_urb(struct urb *urb)
261 {
262 	struct usb_serial_port *port = urb->context;
263 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
264 	struct tty_struct *tty;
265 	unsigned char *data = urb->transfer_buffer;
266 	unsigned long flags;
267 	unsigned char status;
268 	char tty_flag;
269 
270 	/* Update line status */
271 	tty_flag = TTY_NORMAL;
272 
273 	spin_lock_irqsave(&priv->lock, flags);
274 	status = priv->last_lsr;
275 	priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
276 	spin_unlock_irqrestore(&priv->lock, flags);
277 
278 	if (!urb->actual_length)
279 		return;
280 
281 	tty = tty_port_tty_get(&port->port);
282 	if (!tty)
283 		return;
284 
285 	if (status & BELKIN_SA_LSR_ERR) {
286 		/* Break takes precedence over parity, which takes precedence
287 		 * over framing errors. */
288 		if (status & BELKIN_SA_LSR_BI)
289 			tty_flag = TTY_BREAK;
290 		else if (status & BELKIN_SA_LSR_PE)
291 			tty_flag = TTY_PARITY;
292 		else if (status & BELKIN_SA_LSR_FE)
293 			tty_flag = TTY_FRAME;
294 		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
295 
296 		/* Overrun is special, not associated with a char. */
297 		if (status & BELKIN_SA_LSR_OE)
298 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
299 	}
300 
301 	tty_insert_flip_string_fixed_flag(tty, data, tty_flag,
302 							urb->actual_length);
303 	tty_flip_buffer_push(tty);
304 	tty_kref_put(tty);
305 }
306 
307 static void belkin_sa_set_termios(struct tty_struct *tty,
308 		struct usb_serial_port *port, struct ktermios *old_termios)
309 {
310 	struct usb_serial *serial = port->serial;
311 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
312 	unsigned int iflag;
313 	unsigned int cflag;
314 	unsigned int old_iflag = 0;
315 	unsigned int old_cflag = 0;
316 	__u16 urb_value = 0; /* Will hold the new flags */
317 	unsigned long flags;
318 	unsigned long control_state;
319 	int bad_flow_control;
320 	speed_t baud;
321 	struct ktermios *termios = tty->termios;
322 
323 	iflag = termios->c_iflag;
324 	cflag = termios->c_cflag;
325 
326 	termios->c_cflag &= ~CMSPAR;
327 
328 	/* get a local copy of the current port settings */
329 	spin_lock_irqsave(&priv->lock, flags);
330 	control_state = priv->control_state;
331 	bad_flow_control = priv->bad_flow_control;
332 	spin_unlock_irqrestore(&priv->lock, flags);
333 
334 	old_iflag = old_termios->c_iflag;
335 	old_cflag = old_termios->c_cflag;
336 
337 	/* Set the baud rate */
338 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
339 		/* reassert DTR and (maybe) RTS on transition from B0 */
340 		if ((old_cflag & CBAUD) == B0) {
341 			control_state |= (TIOCM_DTR|TIOCM_RTS);
342 			if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
343 				dev_err(&port->dev, "Set DTR error\n");
344 			/* don't set RTS if using hardware flow control */
345 			if (!(old_cflag & CRTSCTS))
346 				if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
347 								, 1) < 0)
348 					dev_err(&port->dev, "Set RTS error\n");
349 		}
350 	}
351 
352 	baud = tty_get_baud_rate(tty);
353 	if (baud) {
354 		urb_value = BELKIN_SA_BAUD(baud);
355 		/* Clip to maximum speed */
356 		if (urb_value == 0)
357 			urb_value = 1;
358 		/* Turn it back into a resulting real baud rate */
359 		baud = BELKIN_SA_BAUD(urb_value);
360 
361 		/* Report the actual baud rate back to the caller */
362 		tty_encode_baud_rate(tty, baud, baud);
363 		if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
364 			dev_err(&port->dev, "Set baudrate error\n");
365 	} else {
366 		/* Disable flow control */
367 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
368 						BELKIN_SA_FLOW_NONE) < 0)
369 			dev_err(&port->dev, "Disable flowcontrol error\n");
370 		/* Drop RTS and DTR */
371 		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
372 		if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
373 			dev_err(&port->dev, "DTR LOW error\n");
374 		if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
375 			dev_err(&port->dev, "RTS LOW error\n");
376 	}
377 
378 	/* set the parity */
379 	if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
380 		if (cflag & PARENB)
381 			urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
382 						: BELKIN_SA_PARITY_EVEN;
383 		else
384 			urb_value = BELKIN_SA_PARITY_NONE;
385 		if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
386 			dev_err(&port->dev, "Set parity error\n");
387 	}
388 
389 	/* set the number of data bits */
390 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
391 		switch (cflag & CSIZE) {
392 		case CS5:
393 			urb_value = BELKIN_SA_DATA_BITS(5);
394 			break;
395 		case CS6:
396 			urb_value = BELKIN_SA_DATA_BITS(6);
397 			break;
398 		case CS7:
399 			urb_value = BELKIN_SA_DATA_BITS(7);
400 			break;
401 		case CS8:
402 			urb_value = BELKIN_SA_DATA_BITS(8);
403 			break;
404 		default: dbg("CSIZE was not CS5-CS8, using default of 8");
405 			urb_value = BELKIN_SA_DATA_BITS(8);
406 			break;
407 		}
408 		if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
409 			dev_err(&port->dev, "Set data bits error\n");
410 	}
411 
412 	/* set the number of stop bits */
413 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
414 		urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
415 						: BELKIN_SA_STOP_BITS(1);
416 		if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
417 							urb_value) < 0)
418 			dev_err(&port->dev, "Set stop bits error\n");
419 	}
420 
421 	/* Set flow control */
422 	if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
423 		((cflag ^ old_cflag) & CRTSCTS)) {
424 		urb_value = 0;
425 		if ((iflag & IXOFF) || (iflag & IXON))
426 			urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
427 		else
428 			urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
429 
430 		if (cflag & CRTSCTS)
431 			urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
432 		else
433 			urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
434 
435 		if (bad_flow_control)
436 			urb_value &= ~(BELKIN_SA_FLOW_IRTS);
437 
438 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
439 			dev_err(&port->dev, "Set flow control error\n");
440 	}
441 
442 	/* save off the modified port settings */
443 	spin_lock_irqsave(&priv->lock, flags);
444 	priv->control_state = control_state;
445 	spin_unlock_irqrestore(&priv->lock, flags);
446 }
447 
448 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
449 {
450 	struct usb_serial_port *port = tty->driver_data;
451 	struct usb_serial *serial = port->serial;
452 
453 	if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
454 		dev_err(&port->dev, "Set break_ctl %d\n", break_state);
455 }
456 
457 static int belkin_sa_tiocmget(struct tty_struct *tty)
458 {
459 	struct usb_serial_port *port = tty->driver_data;
460 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
461 	unsigned long control_state;
462 	unsigned long flags;
463 
464 	dbg("%s", __func__);
465 
466 	spin_lock_irqsave(&priv->lock, flags);
467 	control_state = priv->control_state;
468 	spin_unlock_irqrestore(&priv->lock, flags);
469 
470 	return control_state;
471 }
472 
473 static int belkin_sa_tiocmset(struct tty_struct *tty,
474 			       unsigned int set, unsigned int clear)
475 {
476 	struct usb_serial_port *port = tty->driver_data;
477 	struct usb_serial *serial = port->serial;
478 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
479 	unsigned long control_state;
480 	unsigned long flags;
481 	int retval;
482 	int rts = 0;
483 	int dtr = 0;
484 
485 	dbg("%s", __func__);
486 
487 	spin_lock_irqsave(&priv->lock, flags);
488 	control_state = priv->control_state;
489 
490 	if (set & TIOCM_RTS) {
491 		control_state |= TIOCM_RTS;
492 		rts = 1;
493 	}
494 	if (set & TIOCM_DTR) {
495 		control_state |= TIOCM_DTR;
496 		dtr = 1;
497 	}
498 	if (clear & TIOCM_RTS) {
499 		control_state &= ~TIOCM_RTS;
500 		rts = 0;
501 	}
502 	if (clear & TIOCM_DTR) {
503 		control_state &= ~TIOCM_DTR;
504 		dtr = 0;
505 	}
506 
507 	priv->control_state = control_state;
508 	spin_unlock_irqrestore(&priv->lock, flags);
509 
510 	retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
511 	if (retval < 0) {
512 		dev_err(&port->dev, "Set RTS error %d\n", retval);
513 		goto exit;
514 	}
515 
516 	retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
517 	if (retval < 0) {
518 		dev_err(&port->dev, "Set DTR error %d\n", retval);
519 		goto exit;
520 	}
521 exit:
522 	return retval;
523 }
524 
525 
526 static int __init belkin_sa_init(void)
527 {
528 	int retval;
529 	retval = usb_serial_register(&belkin_device);
530 	if (retval)
531 		goto failed_usb_serial_register;
532 	retval = usb_register(&belkin_driver);
533 	if (retval)
534 		goto failed_usb_register;
535 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
536 	       DRIVER_DESC "\n");
537 	return 0;
538 failed_usb_register:
539 	usb_serial_deregister(&belkin_device);
540 failed_usb_serial_register:
541 	return retval;
542 }
543 
544 static void __exit belkin_sa_exit (void)
545 {
546 	usb_deregister(&belkin_driver);
547 	usb_serial_deregister(&belkin_device);
548 }
549 
550 
551 module_init(belkin_sa_init);
552 module_exit(belkin_sa_exit);
553 
554 MODULE_AUTHOR(DRIVER_AUTHOR);
555 MODULE_DESCRIPTION(DRIVER_DESC);
556 MODULE_VERSION(DRIVER_VERSION);
557 MODULE_LICENSE("GPL");
558 
559 module_param(debug, bool, S_IRUGO | S_IWUSR);
560 MODULE_PARM_DESC(debug, "Debug enabled or not");
561