xref: /linux/drivers/usb/serial/belkin_sa.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
41 #define DRIVER_DESC "USB Belkin Serial converter driver"
42 
43 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
44 static int belkin_sa_port_probe(struct usb_serial_port *port);
45 static int belkin_sa_port_remove(struct usb_serial_port *port);
46 static int  belkin_sa_open(struct tty_struct *tty,
47 			struct usb_serial_port *port);
48 static void belkin_sa_close(struct usb_serial_port *port);
49 static void belkin_sa_read_int_callback(struct urb *urb);
50 static void belkin_sa_process_read_urb(struct urb *urb);
51 static void belkin_sa_set_termios(struct tty_struct *tty,
52 			struct usb_serial_port *port, struct ktermios * old);
53 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
54 static int  belkin_sa_tiocmget(struct tty_struct *tty);
55 static int  belkin_sa_tiocmset(struct tty_struct *tty,
56 					unsigned int set, unsigned int clear);
57 
58 
59 static const struct usb_device_id id_table[] = {
60 	{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
61 	{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
62 	{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
63 	{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
64 	{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
65 	{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
66 	{ }	/* Terminating entry */
67 };
68 MODULE_DEVICE_TABLE(usb, id_table);
69 
70 /* All of the device info needed for the serial converters */
71 static struct usb_serial_driver belkin_device = {
72 	.driver = {
73 		.owner =	THIS_MODULE,
74 		.name =		"belkin",
75 	},
76 	.description =		"Belkin / Peracom / GoHubs USB Serial Adapter",
77 	.id_table =		id_table,
78 	.num_ports =		1,
79 	.open =			belkin_sa_open,
80 	.close =		belkin_sa_close,
81 	.read_int_callback =	belkin_sa_read_int_callback,
82 	.process_read_urb =	belkin_sa_process_read_urb,
83 	.set_termios =		belkin_sa_set_termios,
84 	.break_ctl =		belkin_sa_break_ctl,
85 	.tiocmget =		belkin_sa_tiocmget,
86 	.tiocmset =		belkin_sa_tiocmset,
87 	.port_probe =		belkin_sa_port_probe,
88 	.port_remove =		belkin_sa_port_remove,
89 };
90 
91 static struct usb_serial_driver * const serial_drivers[] = {
92 	&belkin_device, NULL
93 };
94 
95 struct belkin_sa_private {
96 	spinlock_t		lock;
97 	unsigned long		control_state;
98 	unsigned char		last_lsr;
99 	unsigned char		last_msr;
100 	int			bad_flow_control;
101 };
102 
103 
104 /*
105  * ***************************************************************************
106  * Belkin USB Serial Adapter F5U103 specific driver functions
107  * ***************************************************************************
108  */
109 
110 #define WDR_TIMEOUT 5000 /* default urb timeout */
111 
112 /* assumes that struct usb_serial *serial is available */
113 #define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
114 					    (c), BELKIN_SA_SET_REQUEST_TYPE, \
115 					    (v), 0, NULL, 0, WDR_TIMEOUT)
116 
117 static int belkin_sa_port_probe(struct usb_serial_port *port)
118 {
119 	struct usb_device *dev = port->serial->dev;
120 	struct belkin_sa_private *priv;
121 
122 	priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
123 	if (!priv)
124 		return -ENOMEM;
125 
126 	spin_lock_init(&priv->lock);
127 	priv->control_state = 0;
128 	priv->last_lsr = 0;
129 	priv->last_msr = 0;
130 	/* see comments at top of file */
131 	priv->bad_flow_control =
132 		(le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
133 	dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
134 					le16_to_cpu(dev->descriptor.bcdDevice),
135 					priv->bad_flow_control);
136 
137 	usb_set_serial_port_data(port, priv);
138 
139 	return 0;
140 }
141 
142 static int belkin_sa_port_remove(struct usb_serial_port *port)
143 {
144 	struct belkin_sa_private *priv;
145 
146 	priv = usb_get_serial_port_data(port);
147 	kfree(priv);
148 
149 	return 0;
150 }
151 
152 static int belkin_sa_open(struct tty_struct *tty,
153 					struct usb_serial_port *port)
154 {
155 	int retval;
156 
157 	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
158 	if (retval) {
159 		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
160 		return retval;
161 	}
162 
163 	retval = usb_serial_generic_open(tty, port);
164 	if (retval)
165 		usb_kill_urb(port->interrupt_in_urb);
166 
167 	return retval;
168 }
169 
170 static void belkin_sa_close(struct usb_serial_port *port)
171 {
172 	usb_serial_generic_close(port);
173 	usb_kill_urb(port->interrupt_in_urb);
174 }
175 
176 static void belkin_sa_read_int_callback(struct urb *urb)
177 {
178 	struct usb_serial_port *port = urb->context;
179 	struct belkin_sa_private *priv;
180 	unsigned char *data = urb->transfer_buffer;
181 	int retval;
182 	int status = urb->status;
183 	unsigned long flags;
184 
185 	switch (status) {
186 	case 0:
187 		/* success */
188 		break;
189 	case -ECONNRESET:
190 	case -ENOENT:
191 	case -ESHUTDOWN:
192 		/* this urb is terminated, clean up */
193 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
194 			__func__, status);
195 		return;
196 	default:
197 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
198 			__func__, status);
199 		goto exit;
200 	}
201 
202 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
203 
204 	/* Handle known interrupt data */
205 	/* ignore data[0] and data[1] */
206 
207 	priv = usb_get_serial_port_data(port);
208 	spin_lock_irqsave(&priv->lock, flags);
209 	priv->last_msr = data[BELKIN_SA_MSR_INDEX];
210 
211 	/* Record Control Line states */
212 	if (priv->last_msr & BELKIN_SA_MSR_DSR)
213 		priv->control_state |= TIOCM_DSR;
214 	else
215 		priv->control_state &= ~TIOCM_DSR;
216 
217 	if (priv->last_msr & BELKIN_SA_MSR_CTS)
218 		priv->control_state |= TIOCM_CTS;
219 	else
220 		priv->control_state &= ~TIOCM_CTS;
221 
222 	if (priv->last_msr & BELKIN_SA_MSR_RI)
223 		priv->control_state |= TIOCM_RI;
224 	else
225 		priv->control_state &= ~TIOCM_RI;
226 
227 	if (priv->last_msr & BELKIN_SA_MSR_CD)
228 		priv->control_state |= TIOCM_CD;
229 	else
230 		priv->control_state &= ~TIOCM_CD;
231 
232 	priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
233 	spin_unlock_irqrestore(&priv->lock, flags);
234 exit:
235 	retval = usb_submit_urb(urb, GFP_ATOMIC);
236 	if (retval)
237 		dev_err(&port->dev, "%s - usb_submit_urb failed with "
238 			"result %d\n", __func__, retval);
239 }
240 
241 static void belkin_sa_process_read_urb(struct urb *urb)
242 {
243 	struct usb_serial_port *port = urb->context;
244 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
245 	unsigned char *data = urb->transfer_buffer;
246 	unsigned long flags;
247 	unsigned char status;
248 	char tty_flag;
249 
250 	/* Update line status */
251 	tty_flag = TTY_NORMAL;
252 
253 	spin_lock_irqsave(&priv->lock, flags);
254 	status = priv->last_lsr;
255 	priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
256 	spin_unlock_irqrestore(&priv->lock, flags);
257 
258 	if (!urb->actual_length)
259 		return;
260 
261 	if (status & BELKIN_SA_LSR_ERR) {
262 		/* Break takes precedence over parity, which takes precedence
263 		 * over framing errors. */
264 		if (status & BELKIN_SA_LSR_BI)
265 			tty_flag = TTY_BREAK;
266 		else if (status & BELKIN_SA_LSR_PE)
267 			tty_flag = TTY_PARITY;
268 		else if (status & BELKIN_SA_LSR_FE)
269 			tty_flag = TTY_FRAME;
270 		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
271 
272 		/* Overrun is special, not associated with a char. */
273 		if (status & BELKIN_SA_LSR_OE)
274 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
275 	}
276 
277 	tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
278 							urb->actual_length);
279 	tty_flip_buffer_push(&port->port);
280 }
281 
282 static void belkin_sa_set_termios(struct tty_struct *tty,
283 		struct usb_serial_port *port, struct ktermios *old_termios)
284 {
285 	struct usb_serial *serial = port->serial;
286 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
287 	unsigned int iflag;
288 	unsigned int cflag;
289 	unsigned int old_iflag = 0;
290 	unsigned int old_cflag = 0;
291 	__u16 urb_value = 0; /* Will hold the new flags */
292 	unsigned long flags;
293 	unsigned long control_state;
294 	int bad_flow_control;
295 	speed_t baud;
296 	struct ktermios *termios = &tty->termios;
297 
298 	iflag = termios->c_iflag;
299 	cflag = termios->c_cflag;
300 
301 	termios->c_cflag &= ~CMSPAR;
302 
303 	/* get a local copy of the current port settings */
304 	spin_lock_irqsave(&priv->lock, flags);
305 	control_state = priv->control_state;
306 	bad_flow_control = priv->bad_flow_control;
307 	spin_unlock_irqrestore(&priv->lock, flags);
308 
309 	old_iflag = old_termios->c_iflag;
310 	old_cflag = old_termios->c_cflag;
311 
312 	/* Set the baud rate */
313 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
314 		/* reassert DTR and (maybe) RTS on transition from B0 */
315 		if ((old_cflag & CBAUD) == B0) {
316 			control_state |= (TIOCM_DTR|TIOCM_RTS);
317 			if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
318 				dev_err(&port->dev, "Set DTR error\n");
319 			/* don't set RTS if using hardware flow control */
320 			if (!(old_cflag & CRTSCTS))
321 				if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
322 								, 1) < 0)
323 					dev_err(&port->dev, "Set RTS error\n");
324 		}
325 	}
326 
327 	baud = tty_get_baud_rate(tty);
328 	if (baud) {
329 		urb_value = BELKIN_SA_BAUD(baud);
330 		/* Clip to maximum speed */
331 		if (urb_value == 0)
332 			urb_value = 1;
333 		/* Turn it back into a resulting real baud rate */
334 		baud = BELKIN_SA_BAUD(urb_value);
335 
336 		/* Report the actual baud rate back to the caller */
337 		tty_encode_baud_rate(tty, baud, baud);
338 		if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
339 			dev_err(&port->dev, "Set baudrate error\n");
340 	} else {
341 		/* Disable flow control */
342 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
343 						BELKIN_SA_FLOW_NONE) < 0)
344 			dev_err(&port->dev, "Disable flowcontrol error\n");
345 		/* Drop RTS and DTR */
346 		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
347 		if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
348 			dev_err(&port->dev, "DTR LOW error\n");
349 		if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
350 			dev_err(&port->dev, "RTS LOW error\n");
351 	}
352 
353 	/* set the parity */
354 	if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
355 		if (cflag & PARENB)
356 			urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
357 						: BELKIN_SA_PARITY_EVEN;
358 		else
359 			urb_value = BELKIN_SA_PARITY_NONE;
360 		if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
361 			dev_err(&port->dev, "Set parity error\n");
362 	}
363 
364 	/* set the number of data bits */
365 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
366 		switch (cflag & CSIZE) {
367 		case CS5:
368 			urb_value = BELKIN_SA_DATA_BITS(5);
369 			break;
370 		case CS6:
371 			urb_value = BELKIN_SA_DATA_BITS(6);
372 			break;
373 		case CS7:
374 			urb_value = BELKIN_SA_DATA_BITS(7);
375 			break;
376 		case CS8:
377 			urb_value = BELKIN_SA_DATA_BITS(8);
378 			break;
379 		default:
380 			dev_dbg(&port->dev,
381 				"CSIZE was not CS5-CS8, using default of 8\n");
382 			urb_value = BELKIN_SA_DATA_BITS(8);
383 			break;
384 		}
385 		if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
386 			dev_err(&port->dev, "Set data bits error\n");
387 	}
388 
389 	/* set the number of stop bits */
390 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
391 		urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
392 						: BELKIN_SA_STOP_BITS(1);
393 		if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
394 							urb_value) < 0)
395 			dev_err(&port->dev, "Set stop bits error\n");
396 	}
397 
398 	/* Set flow control */
399 	if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
400 		((cflag ^ old_cflag) & CRTSCTS)) {
401 		urb_value = 0;
402 		if ((iflag & IXOFF) || (iflag & IXON))
403 			urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
404 		else
405 			urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
406 
407 		if (cflag & CRTSCTS)
408 			urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
409 		else
410 			urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
411 
412 		if (bad_flow_control)
413 			urb_value &= ~(BELKIN_SA_FLOW_IRTS);
414 
415 		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
416 			dev_err(&port->dev, "Set flow control error\n");
417 	}
418 
419 	/* save off the modified port settings */
420 	spin_lock_irqsave(&priv->lock, flags);
421 	priv->control_state = control_state;
422 	spin_unlock_irqrestore(&priv->lock, flags);
423 }
424 
425 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
426 {
427 	struct usb_serial_port *port = tty->driver_data;
428 	struct usb_serial *serial = port->serial;
429 
430 	if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
431 		dev_err(&port->dev, "Set break_ctl %d\n", break_state);
432 }
433 
434 static int belkin_sa_tiocmget(struct tty_struct *tty)
435 {
436 	struct usb_serial_port *port = tty->driver_data;
437 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
438 	unsigned long control_state;
439 	unsigned long flags;
440 
441 	spin_lock_irqsave(&priv->lock, flags);
442 	control_state = priv->control_state;
443 	spin_unlock_irqrestore(&priv->lock, flags);
444 
445 	return control_state;
446 }
447 
448 static int belkin_sa_tiocmset(struct tty_struct *tty,
449 			       unsigned int set, unsigned int clear)
450 {
451 	struct usb_serial_port *port = tty->driver_data;
452 	struct usb_serial *serial = port->serial;
453 	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
454 	unsigned long control_state;
455 	unsigned long flags;
456 	int retval;
457 	int rts = 0;
458 	int dtr = 0;
459 
460 	spin_lock_irqsave(&priv->lock, flags);
461 	control_state = priv->control_state;
462 
463 	if (set & TIOCM_RTS) {
464 		control_state |= TIOCM_RTS;
465 		rts = 1;
466 	}
467 	if (set & TIOCM_DTR) {
468 		control_state |= TIOCM_DTR;
469 		dtr = 1;
470 	}
471 	if (clear & TIOCM_RTS) {
472 		control_state &= ~TIOCM_RTS;
473 		rts = 0;
474 	}
475 	if (clear & TIOCM_DTR) {
476 		control_state &= ~TIOCM_DTR;
477 		dtr = 0;
478 	}
479 
480 	priv->control_state = control_state;
481 	spin_unlock_irqrestore(&priv->lock, flags);
482 
483 	retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
484 	if (retval < 0) {
485 		dev_err(&port->dev, "Set RTS error %d\n", retval);
486 		goto exit;
487 	}
488 
489 	retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
490 	if (retval < 0) {
491 		dev_err(&port->dev, "Set DTR error %d\n", retval);
492 		goto exit;
493 	}
494 exit:
495 	return retval;
496 }
497 
498 module_usb_serial_driver(serial_drivers, id_table);
499 
500 MODULE_AUTHOR(DRIVER_AUTHOR);
501 MODULE_DESCRIPTION(DRIVER_DESC);
502 MODULE_LICENSE("GPL");
503