xref: /openbmc/linux/drivers/usb/serial/belkin_sa.c (revision 05bcf503)
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 /*
41  * Version Information
42  */
43 #define DRIVER_VERSION "v1.3"
44 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
45 #define DRIVER_DESC "USB Belkin Serial converter driver"
46 
47 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
48 static int belkin_sa_port_probe(struct usb_serial_port *port);
49 static int belkin_sa_port_remove(struct usb_serial_port *port);
50 static int  belkin_sa_open(struct tty_struct *tty,
51 			struct usb_serial_port *port);
52 static void belkin_sa_close(struct usb_serial_port *port);
53 static void belkin_sa_read_int_callback(struct urb *urb);
54 static void belkin_sa_process_read_urb(struct urb *urb);
55 static void belkin_sa_set_termios(struct tty_struct *tty,
56 			struct usb_serial_port *port, struct ktermios * old);
57 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
58 static int  belkin_sa_tiocmget(struct tty_struct *tty);
59 static int  belkin_sa_tiocmset(struct tty_struct *tty,
60 					unsigned int set, unsigned int clear);
61 
62 
63 static const struct usb_device_id id_table[] = {
64 	{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
65 	{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
66 	{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
67 	{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
68 	{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
69 	{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
70 	{ }	/* Terminating entry */
71 };
72 MODULE_DEVICE_TABLE(usb, id_table);
73 
74 /* All of the device info needed for the serial converters */
75 static struct usb_serial_driver belkin_device = {
76 	.driver = {
77 		.owner =	THIS_MODULE,
78 		.name =		"belkin",
79 	},
80 	.description =		"Belkin / Peracom / GoHubs USB Serial Adapter",
81 	.id_table =		id_table,
82 	.num_ports =		1,
83 	.open =			belkin_sa_open,
84 	.close =		belkin_sa_close,
85 	.read_int_callback =	belkin_sa_read_int_callback,
86 	.process_read_urb =	belkin_sa_process_read_urb,
87 	.set_termios =		belkin_sa_set_termios,
88 	.break_ctl =		belkin_sa_break_ctl,
89 	.tiocmget =		belkin_sa_tiocmget,
90 	.tiocmset =		belkin_sa_tiocmset,
91 	.port_probe =		belkin_sa_port_probe,
92 	.port_remove =		belkin_sa_port_remove,
93 };
94 
95 static struct usb_serial_driver * const serial_drivers[] = {
96 	&belkin_device, NULL
97 };
98 
99 struct belkin_sa_private {
100 	spinlock_t		lock;
101 	unsigned long		control_state;
102 	unsigned char		last_lsr;
103 	unsigned char		last_msr;
104 	int			bad_flow_control;
105 };
106 
107 
108 /*
109  * ***************************************************************************
110  * Belkin USB Serial Adapter F5U103 specific driver functions
111  * ***************************************************************************
112  */
113 
114 #define WDR_TIMEOUT 5000 /* default urb timeout */
115 
116 /* assumes that struct usb_serial *serial is available */
117 #define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
118 					    (c), BELKIN_SA_SET_REQUEST_TYPE, \
119 					    (v), 0, NULL, 0, WDR_TIMEOUT)
120 
121 static int belkin_sa_port_probe(struct usb_serial_port *port)
122 {
123 	struct usb_device *dev = port->serial->dev;
124 	struct belkin_sa_private *priv;
125 
126 	priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
127 	if (!priv)
128 		return -ENOMEM;
129 
130 	spin_lock_init(&priv->lock);
131 	priv->control_state = 0;
132 	priv->last_lsr = 0;
133 	priv->last_msr = 0;
134 	/* see comments at top of file */
135 	priv->bad_flow_control =
136 		(le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
137 	dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
138 					le16_to_cpu(dev->descriptor.bcdDevice),
139 					priv->bad_flow_control);
140 
141 	usb_set_serial_port_data(port, priv);
142 
143 	return 0;
144 }
145 
146 static int belkin_sa_port_remove(struct usb_serial_port *port)
147 {
148 	struct belkin_sa_private *priv;
149 
150 	priv = usb_get_serial_port_data(port);
151 	kfree(priv);
152 
153 	return 0;
154 }
155 
156 static int belkin_sa_open(struct tty_struct *tty,
157 					struct usb_serial_port *port)
158 {
159 	int retval;
160 
161 	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
162 	if (retval) {
163 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
164 		return retval;
165 	}
166 
167 	retval = usb_serial_generic_open(tty, port);
168 	if (retval)
169 		usb_kill_urb(port->interrupt_in_urb);
170 
171 	return retval;
172 }
173 
174 static void belkin_sa_close(struct usb_serial_port *port)
175 {
176 	usb_serial_generic_close(port);
177 	usb_kill_urb(port->interrupt_in_urb);
178 }
179 
180 static void belkin_sa_read_int_callback(struct urb *urb)
181 {
182 	struct usb_serial_port *port = urb->context;
183 	struct belkin_sa_private *priv;
184 	unsigned char *data = urb->transfer_buffer;
185 	int retval;
186 	int status = urb->status;
187 	unsigned long flags;
188 
189 	switch (status) {
190 	case 0:
191 		/* success */
192 		break;
193 	case -ECONNRESET:
194 	case -ENOENT:
195 	case -ESHUTDOWN:
196 		/* this urb is terminated, clean up */
197 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
198 			__func__, status);
199 		return;
200 	default:
201 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
202 			__func__, status);
203 		goto exit;
204 	}
205 
206 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
207 
208 	/* Handle known interrupt data */
209 	/* ignore data[0] and data[1] */
210 
211 	priv = usb_get_serial_port_data(port);
212 	spin_lock_irqsave(&priv->lock, flags);
213 	priv->last_msr = data[BELKIN_SA_MSR_INDEX];
214 
215 	/* Record Control Line states */
216 	if (priv->last_msr & BELKIN_SA_MSR_DSR)
217 		priv->control_state |= TIOCM_DSR;
218 	else
219 		priv->control_state &= ~TIOCM_DSR;
220 
221 	if (priv->last_msr & BELKIN_SA_MSR_CTS)
222 		priv->control_state |= TIOCM_CTS;
223 	else
224 		priv->control_state &= ~TIOCM_CTS;
225 
226 	if (priv->last_msr & BELKIN_SA_MSR_RI)
227 		priv->control_state |= TIOCM_RI;
228 	else
229 		priv->control_state &= ~TIOCM_RI;
230 
231 	if (priv->last_msr & BELKIN_SA_MSR_CD)
232 		priv->control_state |= TIOCM_CD;
233 	else
234 		priv->control_state &= ~TIOCM_CD;
235 
236 	priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
237 	spin_unlock_irqrestore(&priv->lock, flags);
238 exit:
239 	retval = usb_submit_urb(urb, GFP_ATOMIC);
240 	if (retval)
241 		dev_err(&port->dev, "%s - usb_submit_urb failed with "
242 			"result %d\n", __func__, retval);
243 }
244 
245 static void belkin_sa_process_read_urb(struct urb *urb)
246 {
247 	struct usb_serial_port *port = urb->context;
248 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
249 	struct tty_struct *tty;
250 	unsigned char *data = urb->transfer_buffer;
251 	unsigned long flags;
252 	unsigned char status;
253 	char tty_flag;
254 
255 	/* Update line status */
256 	tty_flag = TTY_NORMAL;
257 
258 	spin_lock_irqsave(&priv->lock, flags);
259 	status = priv->last_lsr;
260 	priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
261 	spin_unlock_irqrestore(&priv->lock, flags);
262 
263 	if (!urb->actual_length)
264 		return;
265 
266 	tty = tty_port_tty_get(&port->port);
267 	if (!tty)
268 		return;
269 
270 	if (status & BELKIN_SA_LSR_ERR) {
271 		/* Break takes precedence over parity, which takes precedence
272 		 * over framing errors. */
273 		if (status & BELKIN_SA_LSR_BI)
274 			tty_flag = TTY_BREAK;
275 		else if (status & BELKIN_SA_LSR_PE)
276 			tty_flag = TTY_PARITY;
277 		else if (status & BELKIN_SA_LSR_FE)
278 			tty_flag = TTY_FRAME;
279 		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
280 
281 		/* Overrun is special, not associated with a char. */
282 		if (status & BELKIN_SA_LSR_OE)
283 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
284 	}
285 
286 	tty_insert_flip_string_fixed_flag(tty, data, tty_flag,
287 							urb->actual_length);
288 	tty_flip_buffer_push(tty);
289 	tty_kref_put(tty);
290 }
291 
292 static void belkin_sa_set_termios(struct tty_struct *tty,
293 		struct usb_serial_port *port, struct ktermios *old_termios)
294 {
295 	struct usb_serial *serial = port->serial;
296 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
297 	unsigned int iflag;
298 	unsigned int cflag;
299 	unsigned int old_iflag = 0;
300 	unsigned int old_cflag = 0;
301 	__u16 urb_value = 0; /* Will hold the new flags */
302 	unsigned long flags;
303 	unsigned long control_state;
304 	int bad_flow_control;
305 	speed_t baud;
306 	struct ktermios *termios = &tty->termios;
307 
308 	iflag = termios->c_iflag;
309 	cflag = termios->c_cflag;
310 
311 	termios->c_cflag &= ~CMSPAR;
312 
313 	/* get a local copy of the current port settings */
314 	spin_lock_irqsave(&priv->lock, flags);
315 	control_state = priv->control_state;
316 	bad_flow_control = priv->bad_flow_control;
317 	spin_unlock_irqrestore(&priv->lock, flags);
318 
319 	old_iflag = old_termios->c_iflag;
320 	old_cflag = old_termios->c_cflag;
321 
322 	/* Set the baud rate */
323 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
324 		/* reassert DTR and (maybe) RTS on transition from B0 */
325 		if ((old_cflag & CBAUD) == B0) {
326 			control_state |= (TIOCM_DTR|TIOCM_RTS);
327 			if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
328 				dev_err(&port->dev, "Set DTR error\n");
329 			/* don't set RTS if using hardware flow control */
330 			if (!(old_cflag & CRTSCTS))
331 				if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
332 								, 1) < 0)
333 					dev_err(&port->dev, "Set RTS error\n");
334 		}
335 	}
336 
337 	baud = tty_get_baud_rate(tty);
338 	if (baud) {
339 		urb_value = BELKIN_SA_BAUD(baud);
340 		/* Clip to maximum speed */
341 		if (urb_value == 0)
342 			urb_value = 1;
343 		/* Turn it back into a resulting real baud rate */
344 		baud = BELKIN_SA_BAUD(urb_value);
345 
346 		/* Report the actual baud rate back to the caller */
347 		tty_encode_baud_rate(tty, baud, baud);
348 		if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
349 			dev_err(&port->dev, "Set baudrate error\n");
350 	} else {
351 		/* Disable flow control */
352 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
353 						BELKIN_SA_FLOW_NONE) < 0)
354 			dev_err(&port->dev, "Disable flowcontrol error\n");
355 		/* Drop RTS and DTR */
356 		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
357 		if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
358 			dev_err(&port->dev, "DTR LOW error\n");
359 		if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
360 			dev_err(&port->dev, "RTS LOW error\n");
361 	}
362 
363 	/* set the parity */
364 	if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
365 		if (cflag & PARENB)
366 			urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
367 						: BELKIN_SA_PARITY_EVEN;
368 		else
369 			urb_value = BELKIN_SA_PARITY_NONE;
370 		if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
371 			dev_err(&port->dev, "Set parity error\n");
372 	}
373 
374 	/* set the number of data bits */
375 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
376 		switch (cflag & CSIZE) {
377 		case CS5:
378 			urb_value = BELKIN_SA_DATA_BITS(5);
379 			break;
380 		case CS6:
381 			urb_value = BELKIN_SA_DATA_BITS(6);
382 			break;
383 		case CS7:
384 			urb_value = BELKIN_SA_DATA_BITS(7);
385 			break;
386 		case CS8:
387 			urb_value = BELKIN_SA_DATA_BITS(8);
388 			break;
389 		default:
390 			dev_dbg(&port->dev,
391 				"CSIZE was not CS5-CS8, using default of 8\n");
392 			urb_value = BELKIN_SA_DATA_BITS(8);
393 			break;
394 		}
395 		if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
396 			dev_err(&port->dev, "Set data bits error\n");
397 	}
398 
399 	/* set the number of stop bits */
400 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
401 		urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
402 						: BELKIN_SA_STOP_BITS(1);
403 		if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
404 							urb_value) < 0)
405 			dev_err(&port->dev, "Set stop bits error\n");
406 	}
407 
408 	/* Set flow control */
409 	if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
410 		((cflag ^ old_cflag) & CRTSCTS)) {
411 		urb_value = 0;
412 		if ((iflag & IXOFF) || (iflag & IXON))
413 			urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
414 		else
415 			urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
416 
417 		if (cflag & CRTSCTS)
418 			urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
419 		else
420 			urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
421 
422 		if (bad_flow_control)
423 			urb_value &= ~(BELKIN_SA_FLOW_IRTS);
424 
425 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
426 			dev_err(&port->dev, "Set flow control error\n");
427 	}
428 
429 	/* save off the modified port settings */
430 	spin_lock_irqsave(&priv->lock, flags);
431 	priv->control_state = control_state;
432 	spin_unlock_irqrestore(&priv->lock, flags);
433 }
434 
435 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
436 {
437 	struct usb_serial_port *port = tty->driver_data;
438 	struct usb_serial *serial = port->serial;
439 
440 	if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
441 		dev_err(&port->dev, "Set break_ctl %d\n", break_state);
442 }
443 
444 static int belkin_sa_tiocmget(struct tty_struct *tty)
445 {
446 	struct usb_serial_port *port = tty->driver_data;
447 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
448 	unsigned long control_state;
449 	unsigned long flags;
450 
451 	spin_lock_irqsave(&priv->lock, flags);
452 	control_state = priv->control_state;
453 	spin_unlock_irqrestore(&priv->lock, flags);
454 
455 	return control_state;
456 }
457 
458 static int belkin_sa_tiocmset(struct tty_struct *tty,
459 			       unsigned int set, unsigned int clear)
460 {
461 	struct usb_serial_port *port = tty->driver_data;
462 	struct usb_serial *serial = port->serial;
463 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
464 	unsigned long control_state;
465 	unsigned long flags;
466 	int retval;
467 	int rts = 0;
468 	int dtr = 0;
469 
470 	spin_lock_irqsave(&priv->lock, flags);
471 	control_state = priv->control_state;
472 
473 	if (set & TIOCM_RTS) {
474 		control_state |= TIOCM_RTS;
475 		rts = 1;
476 	}
477 	if (set & TIOCM_DTR) {
478 		control_state |= TIOCM_DTR;
479 		dtr = 1;
480 	}
481 	if (clear & TIOCM_RTS) {
482 		control_state &= ~TIOCM_RTS;
483 		rts = 0;
484 	}
485 	if (clear & TIOCM_DTR) {
486 		control_state &= ~TIOCM_DTR;
487 		dtr = 0;
488 	}
489 
490 	priv->control_state = control_state;
491 	spin_unlock_irqrestore(&priv->lock, flags);
492 
493 	retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
494 	if (retval < 0) {
495 		dev_err(&port->dev, "Set RTS error %d\n", retval);
496 		goto exit;
497 	}
498 
499 	retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
500 	if (retval < 0) {
501 		dev_err(&port->dev, "Set DTR error %d\n", retval);
502 		goto exit;
503 	}
504 exit:
505 	return retval;
506 }
507 
508 module_usb_serial_driver(serial_drivers, id_table);
509 
510 MODULE_AUTHOR(DRIVER_AUTHOR);
511 MODULE_DESCRIPTION(DRIVER_DESC);
512 MODULE_VERSION(DRIVER_VERSION);
513 MODULE_LICENSE("GPL");
514