xref: /linux/drivers/usb/serial/digi_acceleport.c (revision f49f4ab95c301dbccad0efe85296d908b8ae7ad4)
1 /*
2 *  Digi AccelePort USB-4 and USB-2 Serial Converters
3 *
4 *  Copyright 2000 by Digi International
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  Shamelessly based on Brian Warner's keyspan_pda.c and Greg Kroah-Hartman's
12 *  usb-serial driver.
13 *
14 *  Peter Berger (pberger@brimson.com)
15 *  Al Borchers (borchers@steinerpoint.com)
16 */
17 
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/tty_driver.h>
24 #include <linux/tty_flip.h>
25 #include <linux/module.h>
26 #include <linux/spinlock.h>
27 #include <linux/workqueue.h>
28 #include <linux/uaccess.h>
29 #include <linux/usb.h>
30 #include <linux/wait.h>
31 #include <linux/usb/serial.h>
32 
33 /* Defines */
34 
35 /*
36  * Version Information
37  */
38 #define DRIVER_VERSION "v1.80.1.2"
39 #define DRIVER_AUTHOR "Peter Berger <pberger@brimson.com>, Al Borchers <borchers@steinerpoint.com>"
40 #define DRIVER_DESC "Digi AccelePort USB-2/USB-4 Serial Converter driver"
41 
42 /* port output buffer length -- must be <= transfer buffer length - 2 */
43 /* so we can be sure to send the full buffer in one urb */
44 #define DIGI_OUT_BUF_SIZE		8
45 
46 /* port input buffer length -- must be >= transfer buffer length - 3 */
47 /* so we can be sure to hold at least one full buffer from one urb */
48 #define DIGI_IN_BUF_SIZE		64
49 
50 /* retry timeout while sleeping */
51 #define DIGI_RETRY_TIMEOUT		(HZ/10)
52 
53 /* timeout while waiting for tty output to drain in close */
54 /* this delay is used twice in close, so the total delay could */
55 /* be twice this value */
56 #define DIGI_CLOSE_TIMEOUT		(5*HZ)
57 
58 
59 /* AccelePort USB Defines */
60 
61 /* ids */
62 #define DIGI_VENDOR_ID			0x05c5
63 #define DIGI_2_ID			0x0002	/* USB-2 */
64 #define DIGI_4_ID			0x0004	/* USB-4 */
65 
66 /* commands
67  * "INB": can be used on the in-band endpoint
68  * "OOB": can be used on the out-of-band endpoint
69  */
70 #define DIGI_CMD_SET_BAUD_RATE			0	/* INB, OOB */
71 #define DIGI_CMD_SET_WORD_SIZE			1	/* INB, OOB */
72 #define DIGI_CMD_SET_PARITY			2	/* INB, OOB */
73 #define DIGI_CMD_SET_STOP_BITS			3	/* INB, OOB */
74 #define DIGI_CMD_SET_INPUT_FLOW_CONTROL		4	/* INB, OOB */
75 #define DIGI_CMD_SET_OUTPUT_FLOW_CONTROL	5	/* INB, OOB */
76 #define DIGI_CMD_SET_DTR_SIGNAL			6	/* INB, OOB */
77 #define DIGI_CMD_SET_RTS_SIGNAL			7	/* INB, OOB */
78 #define DIGI_CMD_READ_INPUT_SIGNALS		8	/*      OOB */
79 #define DIGI_CMD_IFLUSH_FIFO			9	/*      OOB */
80 #define DIGI_CMD_RECEIVE_ENABLE			10	/* INB, OOB */
81 #define DIGI_CMD_BREAK_CONTROL			11	/* INB, OOB */
82 #define DIGI_CMD_LOCAL_LOOPBACK			12	/* INB, OOB */
83 #define DIGI_CMD_TRANSMIT_IDLE			13	/* INB, OOB */
84 #define DIGI_CMD_READ_UART_REGISTER		14	/*      OOB */
85 #define DIGI_CMD_WRITE_UART_REGISTER		15	/* INB, OOB */
86 #define DIGI_CMD_AND_UART_REGISTER		16	/* INB, OOB */
87 #define DIGI_CMD_OR_UART_REGISTER		17	/* INB, OOB */
88 #define DIGI_CMD_SEND_DATA			18	/* INB      */
89 #define DIGI_CMD_RECEIVE_DATA			19	/* INB      */
90 #define DIGI_CMD_RECEIVE_DISABLE		20	/* INB      */
91 #define DIGI_CMD_GET_PORT_TYPE			21	/*      OOB */
92 
93 /* baud rates */
94 #define DIGI_BAUD_50				0
95 #define DIGI_BAUD_75				1
96 #define DIGI_BAUD_110				2
97 #define DIGI_BAUD_150				3
98 #define DIGI_BAUD_200				4
99 #define DIGI_BAUD_300				5
100 #define DIGI_BAUD_600				6
101 #define DIGI_BAUD_1200				7
102 #define DIGI_BAUD_1800				8
103 #define DIGI_BAUD_2400				9
104 #define DIGI_BAUD_4800				10
105 #define DIGI_BAUD_7200				11
106 #define DIGI_BAUD_9600				12
107 #define DIGI_BAUD_14400				13
108 #define DIGI_BAUD_19200				14
109 #define DIGI_BAUD_28800				15
110 #define DIGI_BAUD_38400				16
111 #define DIGI_BAUD_57600				17
112 #define DIGI_BAUD_76800				18
113 #define DIGI_BAUD_115200			19
114 #define DIGI_BAUD_153600			20
115 #define DIGI_BAUD_230400			21
116 #define DIGI_BAUD_460800			22
117 
118 /* arguments */
119 #define DIGI_WORD_SIZE_5			0
120 #define DIGI_WORD_SIZE_6			1
121 #define DIGI_WORD_SIZE_7			2
122 #define DIGI_WORD_SIZE_8			3
123 
124 #define DIGI_PARITY_NONE			0
125 #define DIGI_PARITY_ODD				1
126 #define DIGI_PARITY_EVEN			2
127 #define DIGI_PARITY_MARK			3
128 #define DIGI_PARITY_SPACE			4
129 
130 #define DIGI_STOP_BITS_1			0
131 #define DIGI_STOP_BITS_2			1
132 
133 #define DIGI_INPUT_FLOW_CONTROL_XON_XOFF	1
134 #define DIGI_INPUT_FLOW_CONTROL_RTS		2
135 #define DIGI_INPUT_FLOW_CONTROL_DTR		4
136 
137 #define DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF	1
138 #define DIGI_OUTPUT_FLOW_CONTROL_CTS		2
139 #define DIGI_OUTPUT_FLOW_CONTROL_DSR		4
140 
141 #define DIGI_DTR_INACTIVE			0
142 #define DIGI_DTR_ACTIVE				1
143 #define DIGI_DTR_INPUT_FLOW_CONTROL		2
144 
145 #define DIGI_RTS_INACTIVE			0
146 #define DIGI_RTS_ACTIVE				1
147 #define DIGI_RTS_INPUT_FLOW_CONTROL		2
148 #define DIGI_RTS_TOGGLE				3
149 
150 #define DIGI_FLUSH_TX				1
151 #define DIGI_FLUSH_RX				2
152 #define DIGI_RESUME_TX				4 /* clears xoff condition */
153 
154 #define DIGI_TRANSMIT_NOT_IDLE			0
155 #define DIGI_TRANSMIT_IDLE			1
156 
157 #define DIGI_DISABLE				0
158 #define DIGI_ENABLE				1
159 
160 #define DIGI_DEASSERT				0
161 #define DIGI_ASSERT				1
162 
163 /* in band status codes */
164 #define DIGI_OVERRUN_ERROR			4
165 #define DIGI_PARITY_ERROR			8
166 #define DIGI_FRAMING_ERROR			16
167 #define DIGI_BREAK_ERROR			32
168 
169 /* out of band status */
170 #define DIGI_NO_ERROR				0
171 #define DIGI_BAD_FIRST_PARAMETER		1
172 #define DIGI_BAD_SECOND_PARAMETER		2
173 #define DIGI_INVALID_LINE			3
174 #define DIGI_INVALID_OPCODE			4
175 
176 /* input signals */
177 #define DIGI_READ_INPUT_SIGNALS_SLOT		1
178 #define DIGI_READ_INPUT_SIGNALS_ERR		2
179 #define DIGI_READ_INPUT_SIGNALS_BUSY		4
180 #define DIGI_READ_INPUT_SIGNALS_PE		8
181 #define DIGI_READ_INPUT_SIGNALS_CTS		16
182 #define DIGI_READ_INPUT_SIGNALS_DSR		32
183 #define DIGI_READ_INPUT_SIGNALS_RI		64
184 #define DIGI_READ_INPUT_SIGNALS_DCD		128
185 
186 
187 /* Structures */
188 
189 struct digi_serial {
190 	spinlock_t ds_serial_lock;
191 	struct usb_serial_port *ds_oob_port;	/* out-of-band port */
192 	int ds_oob_port_num;			/* index of out-of-band port */
193 	int ds_device_started;
194 };
195 
196 struct digi_port {
197 	spinlock_t dp_port_lock;
198 	int dp_port_num;
199 	int dp_out_buf_len;
200 	unsigned char dp_out_buf[DIGI_OUT_BUF_SIZE];
201 	int dp_write_urb_in_use;
202 	unsigned int dp_modem_signals;
203 	wait_queue_head_t dp_modem_change_wait;
204 	int dp_transmit_idle;
205 	wait_queue_head_t dp_transmit_idle_wait;
206 	int dp_throttled;
207 	int dp_throttle_restart;
208 	wait_queue_head_t dp_flush_wait;
209 	wait_queue_head_t dp_close_wait;	/* wait queue for close */
210 	struct work_struct dp_wakeup_work;
211 	struct usb_serial_port *dp_port;
212 };
213 
214 
215 /* Local Function Declarations */
216 
217 static void digi_wakeup_write(struct usb_serial_port *port);
218 static void digi_wakeup_write_lock(struct work_struct *work);
219 static int digi_write_oob_command(struct usb_serial_port *port,
220 	unsigned char *buf, int count, int interruptible);
221 static int digi_write_inb_command(struct usb_serial_port *port,
222 	unsigned char *buf, int count, unsigned long timeout);
223 static int digi_set_modem_signals(struct usb_serial_port *port,
224 	unsigned int modem_signals, int interruptible);
225 static int digi_transmit_idle(struct usb_serial_port *port,
226 	unsigned long timeout);
227 static void digi_rx_throttle(struct tty_struct *tty);
228 static void digi_rx_unthrottle(struct tty_struct *tty);
229 static void digi_set_termios(struct tty_struct *tty,
230 		struct usb_serial_port *port, struct ktermios *old_termios);
231 static void digi_break_ctl(struct tty_struct *tty, int break_state);
232 static int digi_tiocmget(struct tty_struct *tty);
233 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
234 		unsigned int clear);
235 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
236 		const unsigned char *buf, int count);
237 static void digi_write_bulk_callback(struct urb *urb);
238 static int digi_write_room(struct tty_struct *tty);
239 static int digi_chars_in_buffer(struct tty_struct *tty);
240 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
241 static void digi_close(struct usb_serial_port *port);
242 static void digi_dtr_rts(struct usb_serial_port *port, int on);
243 static int digi_startup_device(struct usb_serial *serial);
244 static int digi_startup(struct usb_serial *serial);
245 static void digi_disconnect(struct usb_serial *serial);
246 static void digi_release(struct usb_serial *serial);
247 static int digi_port_probe(struct usb_serial_port *port);
248 static int digi_port_remove(struct usb_serial_port *port);
249 static void digi_read_bulk_callback(struct urb *urb);
250 static int digi_read_inb_callback(struct urb *urb);
251 static int digi_read_oob_callback(struct urb *urb);
252 
253 
254 static const struct usb_device_id id_table_combined[] = {
255 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
256 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
257 	{ }						/* Terminating entry */
258 };
259 
260 static const struct usb_device_id id_table_2[] = {
261 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
262 	{ }						/* Terminating entry */
263 };
264 
265 static const struct usb_device_id id_table_4[] = {
266 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
267 	{ }						/* Terminating entry */
268 };
269 
270 MODULE_DEVICE_TABLE(usb, id_table_combined);
271 
272 /* device info needed for the Digi serial converter */
273 
274 static struct usb_serial_driver digi_acceleport_2_device = {
275 	.driver = {
276 		.owner =		THIS_MODULE,
277 		.name =			"digi_2",
278 	},
279 	.description =			"Digi 2 port USB adapter",
280 	.id_table =			id_table_2,
281 	.num_ports =			3,
282 	.open =				digi_open,
283 	.close =			digi_close,
284 	.dtr_rts =			digi_dtr_rts,
285 	.write =			digi_write,
286 	.write_room =			digi_write_room,
287 	.write_bulk_callback = 		digi_write_bulk_callback,
288 	.read_bulk_callback =		digi_read_bulk_callback,
289 	.chars_in_buffer =		digi_chars_in_buffer,
290 	.throttle =			digi_rx_throttle,
291 	.unthrottle =			digi_rx_unthrottle,
292 	.set_termios =			digi_set_termios,
293 	.break_ctl =			digi_break_ctl,
294 	.tiocmget =			digi_tiocmget,
295 	.tiocmset =			digi_tiocmset,
296 	.attach =			digi_startup,
297 	.disconnect =			digi_disconnect,
298 	.release =			digi_release,
299 	.port_probe =			digi_port_probe,
300 	.port_remove =			digi_port_remove,
301 };
302 
303 static struct usb_serial_driver digi_acceleport_4_device = {
304 	.driver = {
305 		.owner =		THIS_MODULE,
306 		.name =			"digi_4",
307 	},
308 	.description =			"Digi 4 port USB adapter",
309 	.id_table =			id_table_4,
310 	.num_ports =			4,
311 	.open =				digi_open,
312 	.close =			digi_close,
313 	.write =			digi_write,
314 	.write_room =			digi_write_room,
315 	.write_bulk_callback = 		digi_write_bulk_callback,
316 	.read_bulk_callback =		digi_read_bulk_callback,
317 	.chars_in_buffer =		digi_chars_in_buffer,
318 	.throttle =			digi_rx_throttle,
319 	.unthrottle =			digi_rx_unthrottle,
320 	.set_termios =			digi_set_termios,
321 	.break_ctl =			digi_break_ctl,
322 	.tiocmget =			digi_tiocmget,
323 	.tiocmset =			digi_tiocmset,
324 	.attach =			digi_startup,
325 	.disconnect =			digi_disconnect,
326 	.release =			digi_release,
327 	.port_probe =			digi_port_probe,
328 	.port_remove =			digi_port_remove,
329 };
330 
331 static struct usb_serial_driver * const serial_drivers[] = {
332 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
333 };
334 
335 /* Functions */
336 
337 /*
338  *  Cond Wait Interruptible Timeout Irqrestore
339  *
340  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
341  *  so that wake ups are not lost if they occur between the unlock
342  *  and the sleep.  In other words, spin_unlock_irqrestore and
343  *  interruptible_sleep_on_timeout are "atomic" with respect to
344  *  wake ups.  This is used to implement condition variables.
345  *
346  *  interruptible_sleep_on_timeout is deprecated and has been replaced
347  *  with the equivalent code.
348  */
349 
350 static long cond_wait_interruptible_timeout_irqrestore(
351 	wait_queue_head_t *q, long timeout,
352 	spinlock_t *lock, unsigned long flags)
353 __releases(lock)
354 {
355 	DEFINE_WAIT(wait);
356 
357 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
358 	spin_unlock_irqrestore(lock, flags);
359 	timeout = schedule_timeout(timeout);
360 	finish_wait(q, &wait);
361 
362 	return timeout;
363 }
364 
365 
366 /*
367  *  Digi Wakeup Write
368  *
369  *  Wake up port, line discipline, and tty processes sleeping
370  *  on writes.
371  */
372 
373 static void digi_wakeup_write_lock(struct work_struct *work)
374 {
375 	struct digi_port *priv =
376 			container_of(work, struct digi_port, dp_wakeup_work);
377 	struct usb_serial_port *port = priv->dp_port;
378 	unsigned long flags;
379 
380 	spin_lock_irqsave(&priv->dp_port_lock, flags);
381 	digi_wakeup_write(port);
382 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
383 }
384 
385 static void digi_wakeup_write(struct usb_serial_port *port)
386 {
387 	struct tty_struct *tty = tty_port_tty_get(&port->port);
388 	if (tty) {
389 		tty_wakeup(tty);
390 		tty_kref_put(tty);
391 	}
392 }
393 
394 
395 /*
396  *  Digi Write OOB Command
397  *
398  *  Write commands on the out of band port.  Commands are 4
399  *  bytes each, multiple commands can be sent at once, and
400  *  no command will be split across USB packets.  Returns 0
401  *  if successful, -EINTR if interrupted while sleeping and
402  *  the interruptible flag is true, or a negative error
403  *  returned by usb_submit_urb.
404  */
405 
406 static int digi_write_oob_command(struct usb_serial_port *port,
407 	unsigned char *buf, int count, int interruptible)
408 {
409 	int ret = 0;
410 	int len;
411 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
412 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
413 	unsigned long flags = 0;
414 
415 	dev_dbg(&port->dev,
416 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
417 		oob_priv->dp_port_num, count);
418 
419 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
420 	while (count > 0) {
421 		while (oob_priv->dp_write_urb_in_use) {
422 			cond_wait_interruptible_timeout_irqrestore(
423 				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
424 				&oob_priv->dp_port_lock, flags);
425 			if (interruptible && signal_pending(current))
426 				return -EINTR;
427 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
428 		}
429 
430 		/* len must be a multiple of 4, so commands are not split */
431 		len = min(count, oob_port->bulk_out_size);
432 		if (len > 4)
433 			len &= ~3;
434 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
435 		oob_port->write_urb->transfer_buffer_length = len;
436 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
437 		if (ret == 0) {
438 			oob_priv->dp_write_urb_in_use = 1;
439 			count -= len;
440 			buf += len;
441 		}
442 	}
443 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
444 	if (ret)
445 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
446 			__func__, ret);
447 	return ret;
448 
449 }
450 
451 
452 /*
453  *  Digi Write In Band Command
454  *
455  *  Write commands on the given port.  Commands are 4
456  *  bytes each, multiple commands can be sent at once, and
457  *  no command will be split across USB packets.  If timeout
458  *  is non-zero, write in band command will return after
459  *  waiting unsuccessfully for the URB status to clear for
460  *  timeout ticks.  Returns 0 if successful, or a negative
461  *  error returned by digi_write.
462  */
463 
464 static int digi_write_inb_command(struct usb_serial_port *port,
465 	unsigned char *buf, int count, unsigned long timeout)
466 {
467 	int ret = 0;
468 	int len;
469 	struct digi_port *priv = usb_get_serial_port_data(port);
470 	unsigned char *data = port->write_urb->transfer_buffer;
471 	unsigned long flags = 0;
472 
473 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
474 		priv->dp_port_num, count);
475 
476 	if (timeout)
477 		timeout += jiffies;
478 	else
479 		timeout = ULONG_MAX;
480 
481 	spin_lock_irqsave(&priv->dp_port_lock, flags);
482 	while (count > 0 && ret == 0) {
483 		while (priv->dp_write_urb_in_use &&
484 		       time_before(jiffies, timeout)) {
485 			cond_wait_interruptible_timeout_irqrestore(
486 				&port->write_wait, DIGI_RETRY_TIMEOUT,
487 				&priv->dp_port_lock, flags);
488 			if (signal_pending(current))
489 				return -EINTR;
490 			spin_lock_irqsave(&priv->dp_port_lock, flags);
491 		}
492 
493 		/* len must be a multiple of 4 and small enough to */
494 		/* guarantee the write will send buffered data first, */
495 		/* so commands are in order with data and not split */
496 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
497 		if (len > 4)
498 			len &= ~3;
499 
500 		/* write any buffered data first */
501 		if (priv->dp_out_buf_len > 0) {
502 			data[0] = DIGI_CMD_SEND_DATA;
503 			data[1] = priv->dp_out_buf_len;
504 			memcpy(data + 2, priv->dp_out_buf,
505 				priv->dp_out_buf_len);
506 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
507 			port->write_urb->transfer_buffer_length
508 				= priv->dp_out_buf_len + 2 + len;
509 		} else {
510 			memcpy(data, buf, len);
511 			port->write_urb->transfer_buffer_length = len;
512 		}
513 
514 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
515 		if (ret == 0) {
516 			priv->dp_write_urb_in_use = 1;
517 			priv->dp_out_buf_len = 0;
518 			count -= len;
519 			buf += len;
520 		}
521 
522 	}
523 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
524 
525 	if (ret)
526 		dev_err(&port->dev,
527 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
528 			__func__, ret, priv->dp_port_num);
529 	return ret;
530 }
531 
532 
533 /*
534  *  Digi Set Modem Signals
535  *
536  *  Sets or clears DTR and RTS on the port, according to the
537  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
538  *  for the modem_signals argument.  Returns 0 if successful,
539  *  -EINTR if interrupted while sleeping, or a non-zero error
540  *  returned by usb_submit_urb.
541  */
542 
543 static int digi_set_modem_signals(struct usb_serial_port *port,
544 	unsigned int modem_signals, int interruptible)
545 {
546 
547 	int ret;
548 	struct digi_port *port_priv = usb_get_serial_port_data(port);
549 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
550 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
551 	unsigned char *data = oob_port->write_urb->transfer_buffer;
552 	unsigned long flags = 0;
553 
554 
555 	dev_dbg(&port->dev,
556 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
557 		port_priv->dp_port_num, modem_signals);
558 
559 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
560 	spin_lock(&port_priv->dp_port_lock);
561 
562 	while (oob_priv->dp_write_urb_in_use) {
563 		spin_unlock(&port_priv->dp_port_lock);
564 		cond_wait_interruptible_timeout_irqrestore(
565 			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
566 			&oob_priv->dp_port_lock, flags);
567 		if (interruptible && signal_pending(current))
568 			return -EINTR;
569 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
570 		spin_lock(&port_priv->dp_port_lock);
571 	}
572 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
573 	data[1] = port_priv->dp_port_num;
574 	data[2] = (modem_signals & TIOCM_DTR) ?
575 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
576 	data[3] = 0;
577 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
578 	data[5] = port_priv->dp_port_num;
579 	data[6] = (modem_signals & TIOCM_RTS) ?
580 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
581 	data[7] = 0;
582 
583 	oob_port->write_urb->transfer_buffer_length = 8;
584 
585 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
586 	if (ret == 0) {
587 		oob_priv->dp_write_urb_in_use = 1;
588 		port_priv->dp_modem_signals =
589 			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
590 			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
591 	}
592 	spin_unlock(&port_priv->dp_port_lock);
593 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
594 	if (ret)
595 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
596 			__func__, ret);
597 	return ret;
598 }
599 
600 /*
601  *  Digi Transmit Idle
602  *
603  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
604  *  to go idle.  It returns 0 if successful or a negative error.
605  *
606  *  There are race conditions here if more than one process is calling
607  *  digi_transmit_idle on the same port at the same time.  However, this
608  *  is only called from close, and only one process can be in close on a
609  *  port at a time, so its ok.
610  */
611 
612 static int digi_transmit_idle(struct usb_serial_port *port,
613 	unsigned long timeout)
614 {
615 	int ret;
616 	unsigned char buf[2];
617 	struct digi_port *priv = usb_get_serial_port_data(port);
618 	unsigned long flags = 0;
619 
620 	spin_lock_irqsave(&priv->dp_port_lock, flags);
621 	priv->dp_transmit_idle = 0;
622 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
623 
624 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
625 	buf[1] = 0;
626 
627 	timeout += jiffies;
628 
629 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
630 	if (ret != 0)
631 		return ret;
632 
633 	spin_lock_irqsave(&priv->dp_port_lock, flags);
634 
635 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
636 		cond_wait_interruptible_timeout_irqrestore(
637 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
638 			&priv->dp_port_lock, flags);
639 		if (signal_pending(current))
640 			return -EINTR;
641 		spin_lock_irqsave(&priv->dp_port_lock, flags);
642 	}
643 	priv->dp_transmit_idle = 0;
644 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
645 	return 0;
646 
647 }
648 
649 
650 static void digi_rx_throttle(struct tty_struct *tty)
651 {
652 	unsigned long flags;
653 	struct usb_serial_port *port = tty->driver_data;
654 	struct digi_port *priv = usb_get_serial_port_data(port);
655 
656 	/* stop receiving characters by not resubmitting the read urb */
657 	spin_lock_irqsave(&priv->dp_port_lock, flags);
658 	priv->dp_throttled = 1;
659 	priv->dp_throttle_restart = 0;
660 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
661 }
662 
663 
664 static void digi_rx_unthrottle(struct tty_struct *tty)
665 {
666 	int ret = 0;
667 	unsigned long flags;
668 	struct usb_serial_port *port = tty->driver_data;
669 	struct digi_port *priv = usb_get_serial_port_data(port);
670 
671 	spin_lock_irqsave(&priv->dp_port_lock, flags);
672 
673 	/* restart read chain */
674 	if (priv->dp_throttle_restart)
675 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
676 
677 	/* turn throttle off */
678 	priv->dp_throttled = 0;
679 	priv->dp_throttle_restart = 0;
680 
681 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
682 
683 	if (ret)
684 		dev_err(&port->dev,
685 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
686 			__func__, ret, priv->dp_port_num);
687 }
688 
689 
690 static void digi_set_termios(struct tty_struct *tty,
691 		struct usb_serial_port *port, struct ktermios *old_termios)
692 {
693 	struct digi_port *priv = usb_get_serial_port_data(port);
694 	struct device *dev = &port->dev;
695 	unsigned int iflag = tty->termios.c_iflag;
696 	unsigned int cflag = tty->termios.c_cflag;
697 	unsigned int old_iflag = old_termios->c_iflag;
698 	unsigned int old_cflag = old_termios->c_cflag;
699 	unsigned char buf[32];
700 	unsigned int modem_signals;
701 	int arg, ret;
702 	int i = 0;
703 	speed_t baud;
704 
705 	dev_dbg(dev,
706 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
707 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
708 
709 	/* set baud rate */
710 	baud = tty_get_baud_rate(tty);
711 	if (baud != tty_termios_baud_rate(old_termios)) {
712 		arg = -1;
713 
714 		/* reassert DTR and (maybe) RTS on transition from B0 */
715 		if ((old_cflag&CBAUD) == B0) {
716 			/* don't set RTS if using hardware flow control */
717 			/* and throttling input */
718 			modem_signals = TIOCM_DTR;
719 			if (!(tty->termios.c_cflag & CRTSCTS) ||
720 			    !test_bit(TTY_THROTTLED, &tty->flags))
721 				modem_signals |= TIOCM_RTS;
722 			digi_set_modem_signals(port, modem_signals, 1);
723 		}
724 		switch (baud) {
725 		/* drop DTR and RTS on transition to B0 */
726 		case 0: digi_set_modem_signals(port, 0, 1); break;
727 		case 50: arg = DIGI_BAUD_50; break;
728 		case 75: arg = DIGI_BAUD_75; break;
729 		case 110: arg = DIGI_BAUD_110; break;
730 		case 150: arg = DIGI_BAUD_150; break;
731 		case 200: arg = DIGI_BAUD_200; break;
732 		case 300: arg = DIGI_BAUD_300; break;
733 		case 600: arg = DIGI_BAUD_600; break;
734 		case 1200: arg = DIGI_BAUD_1200; break;
735 		case 1800: arg = DIGI_BAUD_1800; break;
736 		case 2400: arg = DIGI_BAUD_2400; break;
737 		case 4800: arg = DIGI_BAUD_4800; break;
738 		case 9600: arg = DIGI_BAUD_9600; break;
739 		case 19200: arg = DIGI_BAUD_19200; break;
740 		case 38400: arg = DIGI_BAUD_38400; break;
741 		case 57600: arg = DIGI_BAUD_57600; break;
742 		case 115200: arg = DIGI_BAUD_115200; break;
743 		case 230400: arg = DIGI_BAUD_230400; break;
744 		case 460800: arg = DIGI_BAUD_460800; break;
745 		default:
746 			arg = DIGI_BAUD_9600;
747 			baud = 9600;
748 			break;
749 		}
750 		if (arg != -1) {
751 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
752 			buf[i++] = priv->dp_port_num;
753 			buf[i++] = arg;
754 			buf[i++] = 0;
755 		}
756 	}
757 	/* set parity */
758 	tty->termios.c_cflag &= ~CMSPAR;
759 
760 	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
761 		if (cflag&PARENB) {
762 			if (cflag&PARODD)
763 				arg = DIGI_PARITY_ODD;
764 			else
765 				arg = DIGI_PARITY_EVEN;
766 		} else {
767 			arg = DIGI_PARITY_NONE;
768 		}
769 		buf[i++] = DIGI_CMD_SET_PARITY;
770 		buf[i++] = priv->dp_port_num;
771 		buf[i++] = arg;
772 		buf[i++] = 0;
773 	}
774 	/* set word size */
775 	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
776 		arg = -1;
777 		switch (cflag&CSIZE) {
778 		case CS5: arg = DIGI_WORD_SIZE_5; break;
779 		case CS6: arg = DIGI_WORD_SIZE_6; break;
780 		case CS7: arg = DIGI_WORD_SIZE_7; break;
781 		case CS8: arg = DIGI_WORD_SIZE_8; break;
782 		default:
783 			dev_dbg(dev,
784 				"digi_set_termios: can't handle word size %d\n",
785 				(cflag&CSIZE));
786 			break;
787 		}
788 
789 		if (arg != -1) {
790 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
791 			buf[i++] = priv->dp_port_num;
792 			buf[i++] = arg;
793 			buf[i++] = 0;
794 		}
795 
796 	}
797 
798 	/* set stop bits */
799 	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
800 
801 		if ((cflag&CSTOPB))
802 			arg = DIGI_STOP_BITS_2;
803 		else
804 			arg = DIGI_STOP_BITS_1;
805 
806 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
807 		buf[i++] = priv->dp_port_num;
808 		buf[i++] = arg;
809 		buf[i++] = 0;
810 
811 	}
812 
813 	/* set input flow control */
814 	if ((iflag&IXOFF) != (old_iflag&IXOFF)
815 	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
816 		arg = 0;
817 		if (iflag&IXOFF)
818 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
819 		else
820 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
821 
822 		if (cflag&CRTSCTS) {
823 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
824 
825 			/* On USB-4 it is necessary to assert RTS prior */
826 			/* to selecting RTS input flow control.  */
827 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
828 			buf[i++] = priv->dp_port_num;
829 			buf[i++] = DIGI_RTS_ACTIVE;
830 			buf[i++] = 0;
831 
832 		} else {
833 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
834 		}
835 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
836 		buf[i++] = priv->dp_port_num;
837 		buf[i++] = arg;
838 		buf[i++] = 0;
839 	}
840 
841 	/* set output flow control */
842 	if ((iflag & IXON) != (old_iflag & IXON)
843 	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
844 		arg = 0;
845 		if (iflag & IXON)
846 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
847 		else
848 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
849 
850 		if (cflag & CRTSCTS) {
851 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
852 		} else {
853 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
854 			tty->hw_stopped = 0;
855 		}
856 
857 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
858 		buf[i++] = priv->dp_port_num;
859 		buf[i++] = arg;
860 		buf[i++] = 0;
861 	}
862 
863 	/* set receive enable/disable */
864 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
865 		if (cflag & CREAD)
866 			arg = DIGI_ENABLE;
867 		else
868 			arg = DIGI_DISABLE;
869 
870 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
871 		buf[i++] = priv->dp_port_num;
872 		buf[i++] = arg;
873 		buf[i++] = 0;
874 	}
875 	ret = digi_write_oob_command(port, buf, i, 1);
876 	if (ret != 0)
877 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
878 	tty_encode_baud_rate(tty, baud, baud);
879 }
880 
881 
882 static void digi_break_ctl(struct tty_struct *tty, int break_state)
883 {
884 	struct usb_serial_port *port = tty->driver_data;
885 	unsigned char buf[4];
886 
887 	buf[0] = DIGI_CMD_BREAK_CONTROL;
888 	buf[1] = 2;				/* length */
889 	buf[2] = break_state ? 1 : 0;
890 	buf[3] = 0;				/* pad */
891 	digi_write_inb_command(port, buf, 4, 0);
892 }
893 
894 
895 static int digi_tiocmget(struct tty_struct *tty)
896 {
897 	struct usb_serial_port *port = tty->driver_data;
898 	struct digi_port *priv = usb_get_serial_port_data(port);
899 	unsigned int val;
900 	unsigned long flags;
901 
902 	spin_lock_irqsave(&priv->dp_port_lock, flags);
903 	val = priv->dp_modem_signals;
904 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
905 	return val;
906 }
907 
908 
909 static int digi_tiocmset(struct tty_struct *tty,
910 					unsigned int set, unsigned int clear)
911 {
912 	struct usb_serial_port *port = tty->driver_data;
913 	struct digi_port *priv = usb_get_serial_port_data(port);
914 	unsigned int val;
915 	unsigned long flags;
916 
917 	spin_lock_irqsave(&priv->dp_port_lock, flags);
918 	val = (priv->dp_modem_signals & ~clear) | set;
919 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
920 	return digi_set_modem_signals(port, val, 1);
921 }
922 
923 
924 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
925 					const unsigned char *buf, int count)
926 {
927 
928 	int ret, data_len, new_len;
929 	struct digi_port *priv = usb_get_serial_port_data(port);
930 	unsigned char *data = port->write_urb->transfer_buffer;
931 	unsigned long flags = 0;
932 
933 	dev_dbg(&port->dev,
934 		"digi_write: TOP: port=%d, count=%d, in_interrupt=%ld\n",
935 		priv->dp_port_num, count, in_interrupt());
936 
937 	/* copy user data (which can sleep) before getting spin lock */
938 	count = min(count, port->bulk_out_size-2);
939 	count = min(64, count);
940 
941 	/* be sure only one write proceeds at a time */
942 	/* there are races on the port private buffer */
943 	spin_lock_irqsave(&priv->dp_port_lock, flags);
944 
945 	/* wait for urb status clear to submit another urb */
946 	if (priv->dp_write_urb_in_use) {
947 		/* buffer data if count is 1 (probably put_char) if possible */
948 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
949 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
950 			new_len = 1;
951 		} else {
952 			new_len = 0;
953 		}
954 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
955 		return new_len;
956 	}
957 
958 	/* allow space for any buffered data and for new data, up to */
959 	/* transfer buffer size - 2 (for command and length bytes) */
960 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
961 	data_len = new_len + priv->dp_out_buf_len;
962 
963 	if (data_len == 0) {
964 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
965 		return 0;
966 	}
967 
968 	port->write_urb->transfer_buffer_length = data_len+2;
969 
970 	*data++ = DIGI_CMD_SEND_DATA;
971 	*data++ = data_len;
972 
973 	/* copy in buffered data first */
974 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
975 	data += priv->dp_out_buf_len;
976 
977 	/* copy in new data */
978 	memcpy(data, buf, new_len);
979 
980 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
981 	if (ret == 0) {
982 		priv->dp_write_urb_in_use = 1;
983 		ret = new_len;
984 		priv->dp_out_buf_len = 0;
985 	}
986 
987 	/* return length of new data written, or error */
988 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
989 	if (ret < 0)
990 		dev_err_console(port,
991 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
992 			__func__, ret, priv->dp_port_num);
993 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
994 	return ret;
995 
996 }
997 
998 static void digi_write_bulk_callback(struct urb *urb)
999 {
1000 
1001 	struct usb_serial_port *port = urb->context;
1002 	struct usb_serial *serial;
1003 	struct digi_port *priv;
1004 	struct digi_serial *serial_priv;
1005 	int ret = 0;
1006 	int status = urb->status;
1007 
1008 	/* port and serial sanity check */
1009 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
1010 		pr_err("%s: port or port->private is NULL, status=%d\n",
1011 			__func__, status);
1012 		return;
1013 	}
1014 	serial = port->serial;
1015 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
1016 		dev_err(&port->dev,
1017 			"%s: serial or serial->private is NULL, status=%d\n",
1018 			__func__, status);
1019 		return;
1020 	}
1021 
1022 	/* handle oob callback */
1023 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1024 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
1025 		spin_lock(&priv->dp_port_lock);
1026 		priv->dp_write_urb_in_use = 0;
1027 		wake_up_interruptible(&port->write_wait);
1028 		spin_unlock(&priv->dp_port_lock);
1029 		return;
1030 	}
1031 
1032 	/* try to send any buffered data on this port */
1033 	spin_lock(&priv->dp_port_lock);
1034 	priv->dp_write_urb_in_use = 0;
1035 	if (priv->dp_out_buf_len > 0) {
1036 		*((unsigned char *)(port->write_urb->transfer_buffer))
1037 			= (unsigned char)DIGI_CMD_SEND_DATA;
1038 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1039 			= (unsigned char)priv->dp_out_buf_len;
1040 		port->write_urb->transfer_buffer_length =
1041 						priv->dp_out_buf_len + 2;
1042 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1043 			priv->dp_out_buf_len);
1044 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1045 		if (ret == 0) {
1046 			priv->dp_write_urb_in_use = 1;
1047 			priv->dp_out_buf_len = 0;
1048 		}
1049 	}
1050 	/* wake up processes sleeping on writes immediately */
1051 	digi_wakeup_write(port);
1052 	/* also queue up a wakeup at scheduler time, in case we */
1053 	/* lost the race in write_chan(). */
1054 	schedule_work(&priv->dp_wakeup_work);
1055 
1056 	spin_unlock(&priv->dp_port_lock);
1057 	if (ret && ret != -EPERM)
1058 		dev_err_console(port,
1059 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1060 			__func__, ret, priv->dp_port_num);
1061 }
1062 
1063 static int digi_write_room(struct tty_struct *tty)
1064 {
1065 	struct usb_serial_port *port = tty->driver_data;
1066 	struct digi_port *priv = usb_get_serial_port_data(port);
1067 	int room;
1068 	unsigned long flags = 0;
1069 
1070 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1071 
1072 	if (priv->dp_write_urb_in_use)
1073 		room = 0;
1074 	else
1075 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1076 
1077 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1078 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%d\n", priv->dp_port_num, room);
1079 	return room;
1080 
1081 }
1082 
1083 static int digi_chars_in_buffer(struct tty_struct *tty)
1084 {
1085 	struct usb_serial_port *port = tty->driver_data;
1086 	struct digi_port *priv = usb_get_serial_port_data(port);
1087 
1088 	if (priv->dp_write_urb_in_use) {
1089 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1090 			priv->dp_port_num, port->bulk_out_size - 2);
1091 		/* return(port->bulk_out_size - 2); */
1092 		return 256;
1093 	} else {
1094 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1095 			priv->dp_port_num, priv->dp_out_buf_len);
1096 		return priv->dp_out_buf_len;
1097 	}
1098 
1099 }
1100 
1101 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1102 {
1103 	/* Adjust DTR and RTS */
1104 	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
1105 }
1106 
1107 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1108 {
1109 	int ret;
1110 	unsigned char buf[32];
1111 	struct digi_port *priv = usb_get_serial_port_data(port);
1112 	struct ktermios not_termios;
1113 
1114 	/* be sure the device is started up */
1115 	if (digi_startup_device(port->serial) != 0)
1116 		return -ENXIO;
1117 
1118 	/* read modem signals automatically whenever they change */
1119 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1120 	buf[1] = priv->dp_port_num;
1121 	buf[2] = DIGI_ENABLE;
1122 	buf[3] = 0;
1123 
1124 	/* flush fifos */
1125 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1126 	buf[5] = priv->dp_port_num;
1127 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1128 	buf[7] = 0;
1129 
1130 	ret = digi_write_oob_command(port, buf, 8, 1);
1131 	if (ret != 0)
1132 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1133 
1134 	/* set termios settings */
1135 	if (tty) {
1136 		not_termios.c_cflag = ~tty->termios.c_cflag;
1137 		not_termios.c_iflag = ~tty->termios.c_iflag;
1138 		digi_set_termios(tty, port, &not_termios);
1139 	}
1140 	return 0;
1141 }
1142 
1143 
1144 static void digi_close(struct usb_serial_port *port)
1145 {
1146 	DEFINE_WAIT(wait);
1147 	int ret;
1148 	unsigned char buf[32];
1149 	struct digi_port *priv = usb_get_serial_port_data(port);
1150 
1151 	mutex_lock(&port->serial->disc_mutex);
1152 	/* if disconnected, just clear flags */
1153 	if (port->serial->disconnected)
1154 		goto exit;
1155 
1156 	if (port->serial->dev) {
1157 		/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1158 		digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1159 
1160 		/* disable input flow control */
1161 		buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1162 		buf[1] = priv->dp_port_num;
1163 		buf[2] = DIGI_DISABLE;
1164 		buf[3] = 0;
1165 
1166 		/* disable output flow control */
1167 		buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1168 		buf[5] = priv->dp_port_num;
1169 		buf[6] = DIGI_DISABLE;
1170 		buf[7] = 0;
1171 
1172 		/* disable reading modem signals automatically */
1173 		buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1174 		buf[9] = priv->dp_port_num;
1175 		buf[10] = DIGI_DISABLE;
1176 		buf[11] = 0;
1177 
1178 		/* disable receive */
1179 		buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1180 		buf[13] = priv->dp_port_num;
1181 		buf[14] = DIGI_DISABLE;
1182 		buf[15] = 0;
1183 
1184 		/* flush fifos */
1185 		buf[16] = DIGI_CMD_IFLUSH_FIFO;
1186 		buf[17] = priv->dp_port_num;
1187 		buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1188 		buf[19] = 0;
1189 
1190 		ret = digi_write_oob_command(port, buf, 20, 0);
1191 		if (ret != 0)
1192 			dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n", ret);
1193 
1194 		/* wait for final commands on oob port to complete */
1195 		prepare_to_wait(&priv->dp_flush_wait, &wait,
1196 							TASK_INTERRUPTIBLE);
1197 		schedule_timeout(DIGI_CLOSE_TIMEOUT);
1198 		finish_wait(&priv->dp_flush_wait, &wait);
1199 
1200 		/* shutdown any outstanding bulk writes */
1201 		usb_kill_urb(port->write_urb);
1202 	}
1203 exit:
1204 	spin_lock_irq(&priv->dp_port_lock);
1205 	priv->dp_write_urb_in_use = 0;
1206 	wake_up_interruptible(&priv->dp_close_wait);
1207 	spin_unlock_irq(&priv->dp_port_lock);
1208 	mutex_unlock(&port->serial->disc_mutex);
1209 }
1210 
1211 
1212 /*
1213  *  Digi Startup Device
1214  *
1215  *  Starts reads on all ports.  Must be called AFTER startup, with
1216  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1217  */
1218 
1219 static int digi_startup_device(struct usb_serial *serial)
1220 {
1221 	int i, ret = 0;
1222 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1223 	struct usb_serial_port *port;
1224 
1225 	/* be sure this happens exactly once */
1226 	spin_lock(&serial_priv->ds_serial_lock);
1227 	if (serial_priv->ds_device_started) {
1228 		spin_unlock(&serial_priv->ds_serial_lock);
1229 		return 0;
1230 	}
1231 	serial_priv->ds_device_started = 1;
1232 	spin_unlock(&serial_priv->ds_serial_lock);
1233 
1234 	/* start reading from each bulk in endpoint for the device */
1235 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1236 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1237 		port = serial->port[i];
1238 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1239 		if (ret != 0) {
1240 			dev_err(&port->dev,
1241 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1242 				__func__, ret, i);
1243 			break;
1244 		}
1245 	}
1246 	return ret;
1247 }
1248 
1249 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1250 {
1251 	struct digi_port *priv;
1252 
1253 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1254 	if (!priv)
1255 		return -ENOMEM;
1256 
1257 	spin_lock_init(&priv->dp_port_lock);
1258 	priv->dp_port_num = port_num;
1259 	init_waitqueue_head(&priv->dp_modem_change_wait);
1260 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1261 	init_waitqueue_head(&priv->dp_flush_wait);
1262 	init_waitqueue_head(&priv->dp_close_wait);
1263 	INIT_WORK(&priv->dp_wakeup_work, digi_wakeup_write_lock);
1264 	priv->dp_port = port;
1265 
1266 	init_waitqueue_head(&port->write_wait);
1267 
1268 	usb_set_serial_port_data(port, priv);
1269 
1270 	return 0;
1271 }
1272 
1273 static int digi_startup(struct usb_serial *serial)
1274 {
1275 	struct digi_serial *serial_priv;
1276 	int ret;
1277 
1278 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1279 	if (!serial_priv)
1280 		return -ENOMEM;
1281 
1282 	spin_lock_init(&serial_priv->ds_serial_lock);
1283 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1284 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1285 
1286 	ret = digi_port_init(serial_priv->ds_oob_port,
1287 						serial_priv->ds_oob_port_num);
1288 	if (ret) {
1289 		kfree(serial_priv);
1290 		return ret;
1291 	}
1292 
1293 	usb_set_serial_data(serial, serial_priv);
1294 
1295 	return 0;
1296 }
1297 
1298 
1299 static void digi_disconnect(struct usb_serial *serial)
1300 {
1301 	int i;
1302 
1303 	/* stop reads and writes on all ports */
1304 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1305 		usb_kill_urb(serial->port[i]->read_urb);
1306 		usb_kill_urb(serial->port[i]->write_urb);
1307 	}
1308 }
1309 
1310 
1311 static void digi_release(struct usb_serial *serial)
1312 {
1313 	struct digi_serial *serial_priv;
1314 	struct digi_port *priv;
1315 
1316 	serial_priv = usb_get_serial_data(serial);
1317 
1318 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1319 	kfree(priv);
1320 
1321 	kfree(serial_priv);
1322 }
1323 
1324 static int digi_port_probe(struct usb_serial_port *port)
1325 {
1326 	unsigned port_num;
1327 
1328 	port_num = port->number - port->serial->minor;
1329 
1330 	return digi_port_init(port, port_num);
1331 }
1332 
1333 static int digi_port_remove(struct usb_serial_port *port)
1334 {
1335 	struct digi_port *priv;
1336 
1337 	priv = usb_get_serial_port_data(port);
1338 	kfree(priv);
1339 
1340 	return 0;
1341 }
1342 
1343 static void digi_read_bulk_callback(struct urb *urb)
1344 {
1345 	struct usb_serial_port *port = urb->context;
1346 	struct digi_port *priv;
1347 	struct digi_serial *serial_priv;
1348 	int ret;
1349 	int status = urb->status;
1350 
1351 	/* port sanity check, do not resubmit if port is not valid */
1352 	if (port == NULL)
1353 		return;
1354 	priv = usb_get_serial_port_data(port);
1355 	if (priv == NULL) {
1356 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1357 			__func__, status);
1358 		return;
1359 	}
1360 	if (port->serial == NULL ||
1361 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1362 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1363 			"is NULL, status=%d\n", __func__, status);
1364 		return;
1365 	}
1366 
1367 	/* do not resubmit urb if it has any status error */
1368 	if (status) {
1369 		dev_err(&port->dev,
1370 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1371 			__func__, status, priv->dp_port_num);
1372 		return;
1373 	}
1374 
1375 	/* handle oob or inb callback, do not resubmit if error */
1376 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1377 		if (digi_read_oob_callback(urb) != 0)
1378 			return;
1379 	} else {
1380 		if (digi_read_inb_callback(urb) != 0)
1381 			return;
1382 	}
1383 
1384 	/* continue read */
1385 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1386 	if (ret != 0 && ret != -EPERM) {
1387 		dev_err(&port->dev,
1388 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1389 			__func__, ret, priv->dp_port_num);
1390 	}
1391 
1392 }
1393 
1394 /*
1395  *  Digi Read INB Callback
1396  *
1397  *  Digi Read INB Callback handles reads on the in band ports, sending
1398  *  the data on to the tty subsystem.  When called we know port and
1399  *  port->private are not NULL and port->serial has been validated.
1400  *  It returns 0 if successful, 1 if successful but the port is
1401  *  throttled, and -1 if the sanity checks failed.
1402  */
1403 
1404 static int digi_read_inb_callback(struct urb *urb)
1405 {
1406 
1407 	struct usb_serial_port *port = urb->context;
1408 	struct tty_struct *tty;
1409 	struct digi_port *priv = usb_get_serial_port_data(port);
1410 	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
1411 	int len = ((unsigned char *)urb->transfer_buffer)[1];
1412 	int port_status = ((unsigned char *)urb->transfer_buffer)[2];
1413 	unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
1414 	int flag, throttled;
1415 	int status = urb->status;
1416 
1417 	/* do not process callbacks on closed ports */
1418 	/* but do continue the read chain */
1419 	if (urb->status == -ENOENT)
1420 		return 0;
1421 
1422 	/* short/multiple packet check */
1423 	if (urb->actual_length != len + 2) {
1424 		dev_err(&port->dev, "%s: INCOMPLETE OR MULTIPLE PACKET, "
1425 			"status=%d, port=%d, opcode=%d, len=%d, "
1426 			"actual_length=%d, status=%d\n", __func__, status,
1427 			priv->dp_port_num, opcode, len, urb->actual_length,
1428 			port_status);
1429 		return -1;
1430 	}
1431 
1432 	tty = tty_port_tty_get(&port->port);
1433 	spin_lock(&priv->dp_port_lock);
1434 
1435 	/* check for throttle; if set, do not resubmit read urb */
1436 	/* indicate the read chain needs to be restarted on unthrottle */
1437 	throttled = priv->dp_throttled;
1438 	if (throttled)
1439 		priv->dp_throttle_restart = 1;
1440 
1441 	/* receive data */
1442 	if (tty && opcode == DIGI_CMD_RECEIVE_DATA) {
1443 		/* get flag from port_status */
1444 		flag = 0;
1445 
1446 		/* overrun is special, not associated with a char */
1447 		if (port_status & DIGI_OVERRUN_ERROR)
1448 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1449 
1450 		/* break takes precedence over parity, */
1451 		/* which takes precedence over framing errors */
1452 		if (port_status & DIGI_BREAK_ERROR)
1453 			flag = TTY_BREAK;
1454 		else if (port_status & DIGI_PARITY_ERROR)
1455 			flag = TTY_PARITY;
1456 		else if (port_status & DIGI_FRAMING_ERROR)
1457 			flag = TTY_FRAME;
1458 
1459 		/* data length is len-1 (one byte of len is port_status) */
1460 		--len;
1461 		if (len > 0) {
1462 			tty_insert_flip_string_fixed_flag(tty, data, flag,
1463 									len);
1464 			tty_flip_buffer_push(tty);
1465 		}
1466 	}
1467 	spin_unlock(&priv->dp_port_lock);
1468 	tty_kref_put(tty);
1469 
1470 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1471 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1472 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1473 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1474 
1475 	return throttled ? 1 : 0;
1476 
1477 }
1478 
1479 
1480 /*
1481  *  Digi Read OOB Callback
1482  *
1483  *  Digi Read OOB Callback handles reads on the out of band port.
1484  *  When called we know port and port->private are not NULL and
1485  *  the port->serial is valid.  It returns 0 if successful, and
1486  *  -1 if the sanity checks failed.
1487  */
1488 
1489 static int digi_read_oob_callback(struct urb *urb)
1490 {
1491 
1492 	struct usb_serial_port *port = urb->context;
1493 	struct usb_serial *serial = port->serial;
1494 	struct tty_struct *tty;
1495 	struct digi_port *priv = usb_get_serial_port_data(port);
1496 	int opcode, line, status, val;
1497 	int i;
1498 	unsigned int rts;
1499 
1500 	/* handle each oob command */
1501 	for (i = 0; i < urb->actual_length - 3;) {
1502 		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
1503 		line = ((unsigned char *)urb->transfer_buffer)[i++];
1504 		status = ((unsigned char *)urb->transfer_buffer)[i++];
1505 		val = ((unsigned char *)urb->transfer_buffer)[i++];
1506 
1507 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1508 			opcode, line, status, val);
1509 
1510 		if (status != 0 || line >= serial->type->num_ports)
1511 			continue;
1512 
1513 		port = serial->port[line];
1514 
1515 		priv = usb_get_serial_port_data(port);
1516 		if (priv == NULL)
1517 			return -1;
1518 
1519 		tty = tty_port_tty_get(&port->port);
1520 
1521 		rts = 0;
1522 		if (tty)
1523 			rts = tty->termios.c_cflag & CRTSCTS;
1524 
1525 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1526 			spin_lock(&priv->dp_port_lock);
1527 			/* convert from digi flags to termiox flags */
1528 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1529 				priv->dp_modem_signals |= TIOCM_CTS;
1530 				/* port must be open to use tty struct */
1531 				if (rts) {
1532 					tty->hw_stopped = 0;
1533 					digi_wakeup_write(port);
1534 				}
1535 			} else {
1536 				priv->dp_modem_signals &= ~TIOCM_CTS;
1537 				/* port must be open to use tty struct */
1538 				if (rts)
1539 					tty->hw_stopped = 1;
1540 			}
1541 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1542 				priv->dp_modem_signals |= TIOCM_DSR;
1543 			else
1544 				priv->dp_modem_signals &= ~TIOCM_DSR;
1545 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1546 				priv->dp_modem_signals |= TIOCM_RI;
1547 			else
1548 				priv->dp_modem_signals &= ~TIOCM_RI;
1549 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1550 				priv->dp_modem_signals |= TIOCM_CD;
1551 			else
1552 				priv->dp_modem_signals &= ~TIOCM_CD;
1553 
1554 			wake_up_interruptible(&priv->dp_modem_change_wait);
1555 			spin_unlock(&priv->dp_port_lock);
1556 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1557 			spin_lock(&priv->dp_port_lock);
1558 			priv->dp_transmit_idle = 1;
1559 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1560 			spin_unlock(&priv->dp_port_lock);
1561 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1562 			wake_up_interruptible(&priv->dp_flush_wait);
1563 		}
1564 		tty_kref_put(tty);
1565 	}
1566 	return 0;
1567 
1568 }
1569 
1570 module_usb_serial_driver(serial_drivers, id_table_combined);
1571 
1572 MODULE_AUTHOR(DRIVER_AUTHOR);
1573 MODULE_DESCRIPTION(DRIVER_DESC);
1574 MODULE_LICENSE("GPL");
1575