xref: /linux/drivers/usb/serial/digi_acceleport.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
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 #define DRIVER_AUTHOR "Peter Berger <pberger@brimson.com>, Al Borchers <borchers@steinerpoint.com>"
36 #define DRIVER_DESC "Digi AccelePort USB-2/USB-4 Serial Converter driver"
37 
38 /* port output buffer length -- must be <= transfer buffer length - 2 */
39 /* so we can be sure to send the full buffer in one urb */
40 #define DIGI_OUT_BUF_SIZE		8
41 
42 /* port input buffer length -- must be >= transfer buffer length - 3 */
43 /* so we can be sure to hold at least one full buffer from one urb */
44 #define DIGI_IN_BUF_SIZE		64
45 
46 /* retry timeout while sleeping */
47 #define DIGI_RETRY_TIMEOUT		(HZ/10)
48 
49 /* timeout while waiting for tty output to drain in close */
50 /* this delay is used twice in close, so the total delay could */
51 /* be twice this value */
52 #define DIGI_CLOSE_TIMEOUT		(5*HZ)
53 
54 
55 /* AccelePort USB Defines */
56 
57 /* ids */
58 #define DIGI_VENDOR_ID			0x05c5
59 #define DIGI_2_ID			0x0002	/* USB-2 */
60 #define DIGI_4_ID			0x0004	/* USB-4 */
61 
62 /* commands
63  * "INB": can be used on the in-band endpoint
64  * "OOB": can be used on the out-of-band endpoint
65  */
66 #define DIGI_CMD_SET_BAUD_RATE			0	/* INB, OOB */
67 #define DIGI_CMD_SET_WORD_SIZE			1	/* INB, OOB */
68 #define DIGI_CMD_SET_PARITY			2	/* INB, OOB */
69 #define DIGI_CMD_SET_STOP_BITS			3	/* INB, OOB */
70 #define DIGI_CMD_SET_INPUT_FLOW_CONTROL		4	/* INB, OOB */
71 #define DIGI_CMD_SET_OUTPUT_FLOW_CONTROL	5	/* INB, OOB */
72 #define DIGI_CMD_SET_DTR_SIGNAL			6	/* INB, OOB */
73 #define DIGI_CMD_SET_RTS_SIGNAL			7	/* INB, OOB */
74 #define DIGI_CMD_READ_INPUT_SIGNALS		8	/*      OOB */
75 #define DIGI_CMD_IFLUSH_FIFO			9	/*      OOB */
76 #define DIGI_CMD_RECEIVE_ENABLE			10	/* INB, OOB */
77 #define DIGI_CMD_BREAK_CONTROL			11	/* INB, OOB */
78 #define DIGI_CMD_LOCAL_LOOPBACK			12	/* INB, OOB */
79 #define DIGI_CMD_TRANSMIT_IDLE			13	/* INB, OOB */
80 #define DIGI_CMD_READ_UART_REGISTER		14	/*      OOB */
81 #define DIGI_CMD_WRITE_UART_REGISTER		15	/* INB, OOB */
82 #define DIGI_CMD_AND_UART_REGISTER		16	/* INB, OOB */
83 #define DIGI_CMD_OR_UART_REGISTER		17	/* INB, OOB */
84 #define DIGI_CMD_SEND_DATA			18	/* INB      */
85 #define DIGI_CMD_RECEIVE_DATA			19	/* INB      */
86 #define DIGI_CMD_RECEIVE_DISABLE		20	/* INB      */
87 #define DIGI_CMD_GET_PORT_TYPE			21	/*      OOB */
88 
89 /* baud rates */
90 #define DIGI_BAUD_50				0
91 #define DIGI_BAUD_75				1
92 #define DIGI_BAUD_110				2
93 #define DIGI_BAUD_150				3
94 #define DIGI_BAUD_200				4
95 #define DIGI_BAUD_300				5
96 #define DIGI_BAUD_600				6
97 #define DIGI_BAUD_1200				7
98 #define DIGI_BAUD_1800				8
99 #define DIGI_BAUD_2400				9
100 #define DIGI_BAUD_4800				10
101 #define DIGI_BAUD_7200				11
102 #define DIGI_BAUD_9600				12
103 #define DIGI_BAUD_14400				13
104 #define DIGI_BAUD_19200				14
105 #define DIGI_BAUD_28800				15
106 #define DIGI_BAUD_38400				16
107 #define DIGI_BAUD_57600				17
108 #define DIGI_BAUD_76800				18
109 #define DIGI_BAUD_115200			19
110 #define DIGI_BAUD_153600			20
111 #define DIGI_BAUD_230400			21
112 #define DIGI_BAUD_460800			22
113 
114 /* arguments */
115 #define DIGI_WORD_SIZE_5			0
116 #define DIGI_WORD_SIZE_6			1
117 #define DIGI_WORD_SIZE_7			2
118 #define DIGI_WORD_SIZE_8			3
119 
120 #define DIGI_PARITY_NONE			0
121 #define DIGI_PARITY_ODD				1
122 #define DIGI_PARITY_EVEN			2
123 #define DIGI_PARITY_MARK			3
124 #define DIGI_PARITY_SPACE			4
125 
126 #define DIGI_STOP_BITS_1			0
127 #define DIGI_STOP_BITS_2			1
128 
129 #define DIGI_INPUT_FLOW_CONTROL_XON_XOFF	1
130 #define DIGI_INPUT_FLOW_CONTROL_RTS		2
131 #define DIGI_INPUT_FLOW_CONTROL_DTR		4
132 
133 #define DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF	1
134 #define DIGI_OUTPUT_FLOW_CONTROL_CTS		2
135 #define DIGI_OUTPUT_FLOW_CONTROL_DSR		4
136 
137 #define DIGI_DTR_INACTIVE			0
138 #define DIGI_DTR_ACTIVE				1
139 #define DIGI_DTR_INPUT_FLOW_CONTROL		2
140 
141 #define DIGI_RTS_INACTIVE			0
142 #define DIGI_RTS_ACTIVE				1
143 #define DIGI_RTS_INPUT_FLOW_CONTROL		2
144 #define DIGI_RTS_TOGGLE				3
145 
146 #define DIGI_FLUSH_TX				1
147 #define DIGI_FLUSH_RX				2
148 #define DIGI_RESUME_TX				4 /* clears xoff condition */
149 
150 #define DIGI_TRANSMIT_NOT_IDLE			0
151 #define DIGI_TRANSMIT_IDLE			1
152 
153 #define DIGI_DISABLE				0
154 #define DIGI_ENABLE				1
155 
156 #define DIGI_DEASSERT				0
157 #define DIGI_ASSERT				1
158 
159 /* in band status codes */
160 #define DIGI_OVERRUN_ERROR			4
161 #define DIGI_PARITY_ERROR			8
162 #define DIGI_FRAMING_ERROR			16
163 #define DIGI_BREAK_ERROR			32
164 
165 /* out of band status */
166 #define DIGI_NO_ERROR				0
167 #define DIGI_BAD_FIRST_PARAMETER		1
168 #define DIGI_BAD_SECOND_PARAMETER		2
169 #define DIGI_INVALID_LINE			3
170 #define DIGI_INVALID_OPCODE			4
171 
172 /* input signals */
173 #define DIGI_READ_INPUT_SIGNALS_SLOT		1
174 #define DIGI_READ_INPUT_SIGNALS_ERR		2
175 #define DIGI_READ_INPUT_SIGNALS_BUSY		4
176 #define DIGI_READ_INPUT_SIGNALS_PE		8
177 #define DIGI_READ_INPUT_SIGNALS_CTS		16
178 #define DIGI_READ_INPUT_SIGNALS_DSR		32
179 #define DIGI_READ_INPUT_SIGNALS_RI		64
180 #define DIGI_READ_INPUT_SIGNALS_DCD		128
181 
182 
183 /* Structures */
184 
185 struct digi_serial {
186 	spinlock_t ds_serial_lock;
187 	struct usb_serial_port *ds_oob_port;	/* out-of-band port */
188 	int ds_oob_port_num;			/* index of out-of-band port */
189 	int ds_device_started;
190 };
191 
192 struct digi_port {
193 	spinlock_t dp_port_lock;
194 	int dp_port_num;
195 	int dp_out_buf_len;
196 	unsigned char dp_out_buf[DIGI_OUT_BUF_SIZE];
197 	int dp_write_urb_in_use;
198 	unsigned int dp_modem_signals;
199 	wait_queue_head_t dp_modem_change_wait;
200 	int dp_transmit_idle;
201 	wait_queue_head_t dp_transmit_idle_wait;
202 	int dp_throttled;
203 	int dp_throttle_restart;
204 	wait_queue_head_t dp_flush_wait;
205 	wait_queue_head_t dp_close_wait;	/* wait queue for close */
206 	struct work_struct dp_wakeup_work;
207 	struct usb_serial_port *dp_port;
208 };
209 
210 
211 /* Local Function Declarations */
212 
213 static void digi_wakeup_write(struct usb_serial_port *port);
214 static void digi_wakeup_write_lock(struct work_struct *work);
215 static int digi_write_oob_command(struct usb_serial_port *port,
216 	unsigned char *buf, int count, int interruptible);
217 static int digi_write_inb_command(struct usb_serial_port *port,
218 	unsigned char *buf, int count, unsigned long timeout);
219 static int digi_set_modem_signals(struct usb_serial_port *port,
220 	unsigned int modem_signals, int interruptible);
221 static int digi_transmit_idle(struct usb_serial_port *port,
222 	unsigned long timeout);
223 static void digi_rx_throttle(struct tty_struct *tty);
224 static void digi_rx_unthrottle(struct tty_struct *tty);
225 static void digi_set_termios(struct tty_struct *tty,
226 		struct usb_serial_port *port, struct ktermios *old_termios);
227 static void digi_break_ctl(struct tty_struct *tty, int break_state);
228 static int digi_tiocmget(struct tty_struct *tty);
229 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
230 		unsigned int clear);
231 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
232 		const unsigned char *buf, int count);
233 static void digi_write_bulk_callback(struct urb *urb);
234 static int digi_write_room(struct tty_struct *tty);
235 static int digi_chars_in_buffer(struct tty_struct *tty);
236 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
237 static void digi_close(struct usb_serial_port *port);
238 static void digi_dtr_rts(struct usb_serial_port *port, int on);
239 static int digi_startup_device(struct usb_serial *serial);
240 static int digi_startup(struct usb_serial *serial);
241 static void digi_disconnect(struct usb_serial *serial);
242 static void digi_release(struct usb_serial *serial);
243 static int digi_port_probe(struct usb_serial_port *port);
244 static int digi_port_remove(struct usb_serial_port *port);
245 static void digi_read_bulk_callback(struct urb *urb);
246 static int digi_read_inb_callback(struct urb *urb);
247 static int digi_read_oob_callback(struct urb *urb);
248 
249 
250 static const struct usb_device_id id_table_combined[] = {
251 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
252 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
253 	{ }						/* Terminating entry */
254 };
255 
256 static const struct usb_device_id id_table_2[] = {
257 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
258 	{ }						/* Terminating entry */
259 };
260 
261 static const struct usb_device_id id_table_4[] = {
262 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
263 	{ }						/* Terminating entry */
264 };
265 
266 MODULE_DEVICE_TABLE(usb, id_table_combined);
267 
268 /* device info needed for the Digi serial converter */
269 
270 static struct usb_serial_driver digi_acceleport_2_device = {
271 	.driver = {
272 		.owner =		THIS_MODULE,
273 		.name =			"digi_2",
274 	},
275 	.description =			"Digi 2 port USB adapter",
276 	.id_table =			id_table_2,
277 	.num_ports =			3,
278 	.open =				digi_open,
279 	.close =			digi_close,
280 	.dtr_rts =			digi_dtr_rts,
281 	.write =			digi_write,
282 	.write_room =			digi_write_room,
283 	.write_bulk_callback = 		digi_write_bulk_callback,
284 	.read_bulk_callback =		digi_read_bulk_callback,
285 	.chars_in_buffer =		digi_chars_in_buffer,
286 	.throttle =			digi_rx_throttle,
287 	.unthrottle =			digi_rx_unthrottle,
288 	.set_termios =			digi_set_termios,
289 	.break_ctl =			digi_break_ctl,
290 	.tiocmget =			digi_tiocmget,
291 	.tiocmset =			digi_tiocmset,
292 	.attach =			digi_startup,
293 	.disconnect =			digi_disconnect,
294 	.release =			digi_release,
295 	.port_probe =			digi_port_probe,
296 	.port_remove =			digi_port_remove,
297 };
298 
299 static struct usb_serial_driver digi_acceleport_4_device = {
300 	.driver = {
301 		.owner =		THIS_MODULE,
302 		.name =			"digi_4",
303 	},
304 	.description =			"Digi 4 port USB adapter",
305 	.id_table =			id_table_4,
306 	.num_ports =			4,
307 	.open =				digi_open,
308 	.close =			digi_close,
309 	.write =			digi_write,
310 	.write_room =			digi_write_room,
311 	.write_bulk_callback = 		digi_write_bulk_callback,
312 	.read_bulk_callback =		digi_read_bulk_callback,
313 	.chars_in_buffer =		digi_chars_in_buffer,
314 	.throttle =			digi_rx_throttle,
315 	.unthrottle =			digi_rx_unthrottle,
316 	.set_termios =			digi_set_termios,
317 	.break_ctl =			digi_break_ctl,
318 	.tiocmget =			digi_tiocmget,
319 	.tiocmset =			digi_tiocmset,
320 	.attach =			digi_startup,
321 	.disconnect =			digi_disconnect,
322 	.release =			digi_release,
323 	.port_probe =			digi_port_probe,
324 	.port_remove =			digi_port_remove,
325 };
326 
327 static struct usb_serial_driver * const serial_drivers[] = {
328 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
329 };
330 
331 /* Functions */
332 
333 /*
334  *  Cond Wait Interruptible Timeout Irqrestore
335  *
336  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
337  *  so that wake ups are not lost if they occur between the unlock
338  *  and the sleep.  In other words, spin_unlock_irqrestore and
339  *  interruptible_sleep_on_timeout are "atomic" with respect to
340  *  wake ups.  This is used to implement condition variables.
341  *
342  *  interruptible_sleep_on_timeout is deprecated and has been replaced
343  *  with the equivalent code.
344  */
345 
346 static long cond_wait_interruptible_timeout_irqrestore(
347 	wait_queue_head_t *q, long timeout,
348 	spinlock_t *lock, unsigned long flags)
349 __releases(lock)
350 {
351 	DEFINE_WAIT(wait);
352 
353 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
354 	spin_unlock_irqrestore(lock, flags);
355 	timeout = schedule_timeout(timeout);
356 	finish_wait(q, &wait);
357 
358 	return timeout;
359 }
360 
361 
362 /*
363  *  Digi Wakeup Write
364  *
365  *  Wake up port, line discipline, and tty processes sleeping
366  *  on writes.
367  */
368 
369 static void digi_wakeup_write_lock(struct work_struct *work)
370 {
371 	struct digi_port *priv =
372 			container_of(work, struct digi_port, dp_wakeup_work);
373 	struct usb_serial_port *port = priv->dp_port;
374 	unsigned long flags;
375 
376 	spin_lock_irqsave(&priv->dp_port_lock, flags);
377 	digi_wakeup_write(port);
378 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
379 }
380 
381 static void digi_wakeup_write(struct usb_serial_port *port)
382 {
383 	struct tty_struct *tty = tty_port_tty_get(&port->port);
384 	if (tty) {
385 		tty_wakeup(tty);
386 		tty_kref_put(tty);
387 	}
388 }
389 
390 
391 /*
392  *  Digi Write OOB Command
393  *
394  *  Write commands on the out of band port.  Commands are 4
395  *  bytes each, multiple commands can be sent at once, and
396  *  no command will be split across USB packets.  Returns 0
397  *  if successful, -EINTR if interrupted while sleeping and
398  *  the interruptible flag is true, or a negative error
399  *  returned by usb_submit_urb.
400  */
401 
402 static int digi_write_oob_command(struct usb_serial_port *port,
403 	unsigned char *buf, int count, int interruptible)
404 {
405 	int ret = 0;
406 	int len;
407 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
408 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
409 	unsigned long flags = 0;
410 
411 	dev_dbg(&port->dev,
412 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
413 		oob_priv->dp_port_num, count);
414 
415 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
416 	while (count > 0) {
417 		while (oob_priv->dp_write_urb_in_use) {
418 			cond_wait_interruptible_timeout_irqrestore(
419 				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
420 				&oob_priv->dp_port_lock, flags);
421 			if (interruptible && signal_pending(current))
422 				return -EINTR;
423 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
424 		}
425 
426 		/* len must be a multiple of 4, so commands are not split */
427 		len = min(count, oob_port->bulk_out_size);
428 		if (len > 4)
429 			len &= ~3;
430 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
431 		oob_port->write_urb->transfer_buffer_length = len;
432 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
433 		if (ret == 0) {
434 			oob_priv->dp_write_urb_in_use = 1;
435 			count -= len;
436 			buf += len;
437 		}
438 	}
439 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
440 	if (ret)
441 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
442 			__func__, ret);
443 	return ret;
444 
445 }
446 
447 
448 /*
449  *  Digi Write In Band Command
450  *
451  *  Write commands on the given port.  Commands are 4
452  *  bytes each, multiple commands can be sent at once, and
453  *  no command will be split across USB packets.  If timeout
454  *  is non-zero, write in band command will return after
455  *  waiting unsuccessfully for the URB status to clear for
456  *  timeout ticks.  Returns 0 if successful, or a negative
457  *  error returned by digi_write.
458  */
459 
460 static int digi_write_inb_command(struct usb_serial_port *port,
461 	unsigned char *buf, int count, unsigned long timeout)
462 {
463 	int ret = 0;
464 	int len;
465 	struct digi_port *priv = usb_get_serial_port_data(port);
466 	unsigned char *data = port->write_urb->transfer_buffer;
467 	unsigned long flags = 0;
468 
469 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
470 		priv->dp_port_num, count);
471 
472 	if (timeout)
473 		timeout += jiffies;
474 	else
475 		timeout = ULONG_MAX;
476 
477 	spin_lock_irqsave(&priv->dp_port_lock, flags);
478 	while (count > 0 && ret == 0) {
479 		while (priv->dp_write_urb_in_use &&
480 		       time_before(jiffies, timeout)) {
481 			cond_wait_interruptible_timeout_irqrestore(
482 				&port->write_wait, DIGI_RETRY_TIMEOUT,
483 				&priv->dp_port_lock, flags);
484 			if (signal_pending(current))
485 				return -EINTR;
486 			spin_lock_irqsave(&priv->dp_port_lock, flags);
487 		}
488 
489 		/* len must be a multiple of 4 and small enough to */
490 		/* guarantee the write will send buffered data first, */
491 		/* so commands are in order with data and not split */
492 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
493 		if (len > 4)
494 			len &= ~3;
495 
496 		/* write any buffered data first */
497 		if (priv->dp_out_buf_len > 0) {
498 			data[0] = DIGI_CMD_SEND_DATA;
499 			data[1] = priv->dp_out_buf_len;
500 			memcpy(data + 2, priv->dp_out_buf,
501 				priv->dp_out_buf_len);
502 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
503 			port->write_urb->transfer_buffer_length
504 				= priv->dp_out_buf_len + 2 + len;
505 		} else {
506 			memcpy(data, buf, len);
507 			port->write_urb->transfer_buffer_length = len;
508 		}
509 
510 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
511 		if (ret == 0) {
512 			priv->dp_write_urb_in_use = 1;
513 			priv->dp_out_buf_len = 0;
514 			count -= len;
515 			buf += len;
516 		}
517 
518 	}
519 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
520 
521 	if (ret)
522 		dev_err(&port->dev,
523 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
524 			__func__, ret, priv->dp_port_num);
525 	return ret;
526 }
527 
528 
529 /*
530  *  Digi Set Modem Signals
531  *
532  *  Sets or clears DTR and RTS on the port, according to the
533  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
534  *  for the modem_signals argument.  Returns 0 if successful,
535  *  -EINTR if interrupted while sleeping, or a non-zero error
536  *  returned by usb_submit_urb.
537  */
538 
539 static int digi_set_modem_signals(struct usb_serial_port *port,
540 	unsigned int modem_signals, int interruptible)
541 {
542 
543 	int ret;
544 	struct digi_port *port_priv = usb_get_serial_port_data(port);
545 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
546 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
547 	unsigned char *data = oob_port->write_urb->transfer_buffer;
548 	unsigned long flags = 0;
549 
550 
551 	dev_dbg(&port->dev,
552 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
553 		port_priv->dp_port_num, modem_signals);
554 
555 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
556 	spin_lock(&port_priv->dp_port_lock);
557 
558 	while (oob_priv->dp_write_urb_in_use) {
559 		spin_unlock(&port_priv->dp_port_lock);
560 		cond_wait_interruptible_timeout_irqrestore(
561 			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
562 			&oob_priv->dp_port_lock, flags);
563 		if (interruptible && signal_pending(current))
564 			return -EINTR;
565 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
566 		spin_lock(&port_priv->dp_port_lock);
567 	}
568 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
569 	data[1] = port_priv->dp_port_num;
570 	data[2] = (modem_signals & TIOCM_DTR) ?
571 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
572 	data[3] = 0;
573 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
574 	data[5] = port_priv->dp_port_num;
575 	data[6] = (modem_signals & TIOCM_RTS) ?
576 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
577 	data[7] = 0;
578 
579 	oob_port->write_urb->transfer_buffer_length = 8;
580 
581 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
582 	if (ret == 0) {
583 		oob_priv->dp_write_urb_in_use = 1;
584 		port_priv->dp_modem_signals =
585 			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
586 			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
587 	}
588 	spin_unlock(&port_priv->dp_port_lock);
589 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
590 	if (ret)
591 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
592 			__func__, ret);
593 	return ret;
594 }
595 
596 /*
597  *  Digi Transmit Idle
598  *
599  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
600  *  to go idle.  It returns 0 if successful or a negative error.
601  *
602  *  There are race conditions here if more than one process is calling
603  *  digi_transmit_idle on the same port at the same time.  However, this
604  *  is only called from close, and only one process can be in close on a
605  *  port at a time, so its ok.
606  */
607 
608 static int digi_transmit_idle(struct usb_serial_port *port,
609 	unsigned long timeout)
610 {
611 	int ret;
612 	unsigned char buf[2];
613 	struct digi_port *priv = usb_get_serial_port_data(port);
614 	unsigned long flags = 0;
615 
616 	spin_lock_irqsave(&priv->dp_port_lock, flags);
617 	priv->dp_transmit_idle = 0;
618 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
619 
620 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
621 	buf[1] = 0;
622 
623 	timeout += jiffies;
624 
625 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
626 	if (ret != 0)
627 		return ret;
628 
629 	spin_lock_irqsave(&priv->dp_port_lock, flags);
630 
631 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
632 		cond_wait_interruptible_timeout_irqrestore(
633 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
634 			&priv->dp_port_lock, flags);
635 		if (signal_pending(current))
636 			return -EINTR;
637 		spin_lock_irqsave(&priv->dp_port_lock, flags);
638 	}
639 	priv->dp_transmit_idle = 0;
640 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
641 	return 0;
642 
643 }
644 
645 
646 static void digi_rx_throttle(struct tty_struct *tty)
647 {
648 	unsigned long flags;
649 	struct usb_serial_port *port = tty->driver_data;
650 	struct digi_port *priv = usb_get_serial_port_data(port);
651 
652 	/* stop receiving characters by not resubmitting the read urb */
653 	spin_lock_irqsave(&priv->dp_port_lock, flags);
654 	priv->dp_throttled = 1;
655 	priv->dp_throttle_restart = 0;
656 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
657 }
658 
659 
660 static void digi_rx_unthrottle(struct tty_struct *tty)
661 {
662 	int ret = 0;
663 	unsigned long flags;
664 	struct usb_serial_port *port = tty->driver_data;
665 	struct digi_port *priv = usb_get_serial_port_data(port);
666 
667 	spin_lock_irqsave(&priv->dp_port_lock, flags);
668 
669 	/* restart read chain */
670 	if (priv->dp_throttle_restart)
671 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
672 
673 	/* turn throttle off */
674 	priv->dp_throttled = 0;
675 	priv->dp_throttle_restart = 0;
676 
677 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
678 
679 	if (ret)
680 		dev_err(&port->dev,
681 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
682 			__func__, ret, priv->dp_port_num);
683 }
684 
685 
686 static void digi_set_termios(struct tty_struct *tty,
687 		struct usb_serial_port *port, struct ktermios *old_termios)
688 {
689 	struct digi_port *priv = usb_get_serial_port_data(port);
690 	struct device *dev = &port->dev;
691 	unsigned int iflag = tty->termios.c_iflag;
692 	unsigned int cflag = tty->termios.c_cflag;
693 	unsigned int old_iflag = old_termios->c_iflag;
694 	unsigned int old_cflag = old_termios->c_cflag;
695 	unsigned char buf[32];
696 	unsigned int modem_signals;
697 	int arg, ret;
698 	int i = 0;
699 	speed_t baud;
700 
701 	dev_dbg(dev,
702 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
703 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
704 
705 	/* set baud rate */
706 	baud = tty_get_baud_rate(tty);
707 	if (baud != tty_termios_baud_rate(old_termios)) {
708 		arg = -1;
709 
710 		/* reassert DTR and (maybe) RTS on transition from B0 */
711 		if ((old_cflag&CBAUD) == B0) {
712 			/* don't set RTS if using hardware flow control */
713 			/* and throttling input */
714 			modem_signals = TIOCM_DTR;
715 			if (!(tty->termios.c_cflag & CRTSCTS) ||
716 			    !test_bit(TTY_THROTTLED, &tty->flags))
717 				modem_signals |= TIOCM_RTS;
718 			digi_set_modem_signals(port, modem_signals, 1);
719 		}
720 		switch (baud) {
721 		/* drop DTR and RTS on transition to B0 */
722 		case 0: digi_set_modem_signals(port, 0, 1); break;
723 		case 50: arg = DIGI_BAUD_50; break;
724 		case 75: arg = DIGI_BAUD_75; break;
725 		case 110: arg = DIGI_BAUD_110; break;
726 		case 150: arg = DIGI_BAUD_150; break;
727 		case 200: arg = DIGI_BAUD_200; break;
728 		case 300: arg = DIGI_BAUD_300; break;
729 		case 600: arg = DIGI_BAUD_600; break;
730 		case 1200: arg = DIGI_BAUD_1200; break;
731 		case 1800: arg = DIGI_BAUD_1800; break;
732 		case 2400: arg = DIGI_BAUD_2400; break;
733 		case 4800: arg = DIGI_BAUD_4800; break;
734 		case 9600: arg = DIGI_BAUD_9600; break;
735 		case 19200: arg = DIGI_BAUD_19200; break;
736 		case 38400: arg = DIGI_BAUD_38400; break;
737 		case 57600: arg = DIGI_BAUD_57600; break;
738 		case 115200: arg = DIGI_BAUD_115200; break;
739 		case 230400: arg = DIGI_BAUD_230400; break;
740 		case 460800: arg = DIGI_BAUD_460800; break;
741 		default:
742 			arg = DIGI_BAUD_9600;
743 			baud = 9600;
744 			break;
745 		}
746 		if (arg != -1) {
747 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
748 			buf[i++] = priv->dp_port_num;
749 			buf[i++] = arg;
750 			buf[i++] = 0;
751 		}
752 	}
753 	/* set parity */
754 	tty->termios.c_cflag &= ~CMSPAR;
755 
756 	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
757 		if (cflag&PARENB) {
758 			if (cflag&PARODD)
759 				arg = DIGI_PARITY_ODD;
760 			else
761 				arg = DIGI_PARITY_EVEN;
762 		} else {
763 			arg = DIGI_PARITY_NONE;
764 		}
765 		buf[i++] = DIGI_CMD_SET_PARITY;
766 		buf[i++] = priv->dp_port_num;
767 		buf[i++] = arg;
768 		buf[i++] = 0;
769 	}
770 	/* set word size */
771 	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
772 		arg = -1;
773 		switch (cflag&CSIZE) {
774 		case CS5: arg = DIGI_WORD_SIZE_5; break;
775 		case CS6: arg = DIGI_WORD_SIZE_6; break;
776 		case CS7: arg = DIGI_WORD_SIZE_7; break;
777 		case CS8: arg = DIGI_WORD_SIZE_8; break;
778 		default:
779 			dev_dbg(dev,
780 				"digi_set_termios: can't handle word size %d\n",
781 				(cflag&CSIZE));
782 			break;
783 		}
784 
785 		if (arg != -1) {
786 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
787 			buf[i++] = priv->dp_port_num;
788 			buf[i++] = arg;
789 			buf[i++] = 0;
790 		}
791 
792 	}
793 
794 	/* set stop bits */
795 	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
796 
797 		if ((cflag&CSTOPB))
798 			arg = DIGI_STOP_BITS_2;
799 		else
800 			arg = DIGI_STOP_BITS_1;
801 
802 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
803 		buf[i++] = priv->dp_port_num;
804 		buf[i++] = arg;
805 		buf[i++] = 0;
806 
807 	}
808 
809 	/* set input flow control */
810 	if ((iflag&IXOFF) != (old_iflag&IXOFF)
811 	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
812 		arg = 0;
813 		if (iflag&IXOFF)
814 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
815 		else
816 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
817 
818 		if (cflag&CRTSCTS) {
819 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
820 
821 			/* On USB-4 it is necessary to assert RTS prior */
822 			/* to selecting RTS input flow control.  */
823 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
824 			buf[i++] = priv->dp_port_num;
825 			buf[i++] = DIGI_RTS_ACTIVE;
826 			buf[i++] = 0;
827 
828 		} else {
829 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
830 		}
831 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
832 		buf[i++] = priv->dp_port_num;
833 		buf[i++] = arg;
834 		buf[i++] = 0;
835 	}
836 
837 	/* set output flow control */
838 	if ((iflag & IXON) != (old_iflag & IXON)
839 	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
840 		arg = 0;
841 		if (iflag & IXON)
842 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
843 		else
844 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
845 
846 		if (cflag & CRTSCTS) {
847 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
848 		} else {
849 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
850 			tty->hw_stopped = 0;
851 		}
852 
853 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
854 		buf[i++] = priv->dp_port_num;
855 		buf[i++] = arg;
856 		buf[i++] = 0;
857 	}
858 
859 	/* set receive enable/disable */
860 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
861 		if (cflag & CREAD)
862 			arg = DIGI_ENABLE;
863 		else
864 			arg = DIGI_DISABLE;
865 
866 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
867 		buf[i++] = priv->dp_port_num;
868 		buf[i++] = arg;
869 		buf[i++] = 0;
870 	}
871 	ret = digi_write_oob_command(port, buf, i, 1);
872 	if (ret != 0)
873 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
874 	tty_encode_baud_rate(tty, baud, baud);
875 }
876 
877 
878 static void digi_break_ctl(struct tty_struct *tty, int break_state)
879 {
880 	struct usb_serial_port *port = tty->driver_data;
881 	unsigned char buf[4];
882 
883 	buf[0] = DIGI_CMD_BREAK_CONTROL;
884 	buf[1] = 2;				/* length */
885 	buf[2] = break_state ? 1 : 0;
886 	buf[3] = 0;				/* pad */
887 	digi_write_inb_command(port, buf, 4, 0);
888 }
889 
890 
891 static int digi_tiocmget(struct tty_struct *tty)
892 {
893 	struct usb_serial_port *port = tty->driver_data;
894 	struct digi_port *priv = usb_get_serial_port_data(port);
895 	unsigned int val;
896 	unsigned long flags;
897 
898 	spin_lock_irqsave(&priv->dp_port_lock, flags);
899 	val = priv->dp_modem_signals;
900 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
901 	return val;
902 }
903 
904 
905 static int digi_tiocmset(struct tty_struct *tty,
906 					unsigned int set, unsigned int clear)
907 {
908 	struct usb_serial_port *port = tty->driver_data;
909 	struct digi_port *priv = usb_get_serial_port_data(port);
910 	unsigned int val;
911 	unsigned long flags;
912 
913 	spin_lock_irqsave(&priv->dp_port_lock, flags);
914 	val = (priv->dp_modem_signals & ~clear) | set;
915 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
916 	return digi_set_modem_signals(port, val, 1);
917 }
918 
919 
920 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
921 					const unsigned char *buf, int count)
922 {
923 
924 	int ret, data_len, new_len;
925 	struct digi_port *priv = usb_get_serial_port_data(port);
926 	unsigned char *data = port->write_urb->transfer_buffer;
927 	unsigned long flags = 0;
928 
929 	dev_dbg(&port->dev,
930 		"digi_write: TOP: port=%d, count=%d, in_interrupt=%ld\n",
931 		priv->dp_port_num, count, in_interrupt());
932 
933 	/* copy user data (which can sleep) before getting spin lock */
934 	count = min(count, port->bulk_out_size-2);
935 	count = min(64, count);
936 
937 	/* be sure only one write proceeds at a time */
938 	/* there are races on the port private buffer */
939 	spin_lock_irqsave(&priv->dp_port_lock, flags);
940 
941 	/* wait for urb status clear to submit another urb */
942 	if (priv->dp_write_urb_in_use) {
943 		/* buffer data if count is 1 (probably put_char) if possible */
944 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
945 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
946 			new_len = 1;
947 		} else {
948 			new_len = 0;
949 		}
950 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
951 		return new_len;
952 	}
953 
954 	/* allow space for any buffered data and for new data, up to */
955 	/* transfer buffer size - 2 (for command and length bytes) */
956 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
957 	data_len = new_len + priv->dp_out_buf_len;
958 
959 	if (data_len == 0) {
960 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
961 		return 0;
962 	}
963 
964 	port->write_urb->transfer_buffer_length = data_len+2;
965 
966 	*data++ = DIGI_CMD_SEND_DATA;
967 	*data++ = data_len;
968 
969 	/* copy in buffered data first */
970 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
971 	data += priv->dp_out_buf_len;
972 
973 	/* copy in new data */
974 	memcpy(data, buf, new_len);
975 
976 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
977 	if (ret == 0) {
978 		priv->dp_write_urb_in_use = 1;
979 		ret = new_len;
980 		priv->dp_out_buf_len = 0;
981 	}
982 
983 	/* return length of new data written, or error */
984 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
985 	if (ret < 0)
986 		dev_err_console(port,
987 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
988 			__func__, ret, priv->dp_port_num);
989 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
990 	return ret;
991 
992 }
993 
994 static void digi_write_bulk_callback(struct urb *urb)
995 {
996 
997 	struct usb_serial_port *port = urb->context;
998 	struct usb_serial *serial;
999 	struct digi_port *priv;
1000 	struct digi_serial *serial_priv;
1001 	int ret = 0;
1002 	int status = urb->status;
1003 
1004 	/* port and serial sanity check */
1005 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
1006 		pr_err("%s: port or port->private is NULL, status=%d\n",
1007 			__func__, status);
1008 		return;
1009 	}
1010 	serial = port->serial;
1011 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
1012 		dev_err(&port->dev,
1013 			"%s: serial or serial->private is NULL, status=%d\n",
1014 			__func__, status);
1015 		return;
1016 	}
1017 
1018 	/* handle oob callback */
1019 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1020 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
1021 		spin_lock(&priv->dp_port_lock);
1022 		priv->dp_write_urb_in_use = 0;
1023 		wake_up_interruptible(&port->write_wait);
1024 		spin_unlock(&priv->dp_port_lock);
1025 		return;
1026 	}
1027 
1028 	/* try to send any buffered data on this port */
1029 	spin_lock(&priv->dp_port_lock);
1030 	priv->dp_write_urb_in_use = 0;
1031 	if (priv->dp_out_buf_len > 0) {
1032 		*((unsigned char *)(port->write_urb->transfer_buffer))
1033 			= (unsigned char)DIGI_CMD_SEND_DATA;
1034 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1035 			= (unsigned char)priv->dp_out_buf_len;
1036 		port->write_urb->transfer_buffer_length =
1037 						priv->dp_out_buf_len + 2;
1038 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1039 			priv->dp_out_buf_len);
1040 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1041 		if (ret == 0) {
1042 			priv->dp_write_urb_in_use = 1;
1043 			priv->dp_out_buf_len = 0;
1044 		}
1045 	}
1046 	/* wake up processes sleeping on writes immediately */
1047 	digi_wakeup_write(port);
1048 	/* also queue up a wakeup at scheduler time, in case we */
1049 	/* lost the race in write_chan(). */
1050 	schedule_work(&priv->dp_wakeup_work);
1051 
1052 	spin_unlock(&priv->dp_port_lock);
1053 	if (ret && ret != -EPERM)
1054 		dev_err_console(port,
1055 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1056 			__func__, ret, priv->dp_port_num);
1057 }
1058 
1059 static int digi_write_room(struct tty_struct *tty)
1060 {
1061 	struct usb_serial_port *port = tty->driver_data;
1062 	struct digi_port *priv = usb_get_serial_port_data(port);
1063 	int room;
1064 	unsigned long flags = 0;
1065 
1066 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1067 
1068 	if (priv->dp_write_urb_in_use)
1069 		room = 0;
1070 	else
1071 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1072 
1073 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1074 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%d\n", priv->dp_port_num, room);
1075 	return room;
1076 
1077 }
1078 
1079 static int digi_chars_in_buffer(struct tty_struct *tty)
1080 {
1081 	struct usb_serial_port *port = tty->driver_data;
1082 	struct digi_port *priv = usb_get_serial_port_data(port);
1083 
1084 	if (priv->dp_write_urb_in_use) {
1085 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1086 			priv->dp_port_num, port->bulk_out_size - 2);
1087 		/* return(port->bulk_out_size - 2); */
1088 		return 256;
1089 	} else {
1090 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1091 			priv->dp_port_num, priv->dp_out_buf_len);
1092 		return priv->dp_out_buf_len;
1093 	}
1094 
1095 }
1096 
1097 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1098 {
1099 	/* Adjust DTR and RTS */
1100 	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
1101 }
1102 
1103 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1104 {
1105 	int ret;
1106 	unsigned char buf[32];
1107 	struct digi_port *priv = usb_get_serial_port_data(port);
1108 	struct ktermios not_termios;
1109 
1110 	/* be sure the device is started up */
1111 	if (digi_startup_device(port->serial) != 0)
1112 		return -ENXIO;
1113 
1114 	/* read modem signals automatically whenever they change */
1115 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1116 	buf[1] = priv->dp_port_num;
1117 	buf[2] = DIGI_ENABLE;
1118 	buf[3] = 0;
1119 
1120 	/* flush fifos */
1121 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1122 	buf[5] = priv->dp_port_num;
1123 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1124 	buf[7] = 0;
1125 
1126 	ret = digi_write_oob_command(port, buf, 8, 1);
1127 	if (ret != 0)
1128 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1129 
1130 	/* set termios settings */
1131 	if (tty) {
1132 		not_termios.c_cflag = ~tty->termios.c_cflag;
1133 		not_termios.c_iflag = ~tty->termios.c_iflag;
1134 		digi_set_termios(tty, port, &not_termios);
1135 	}
1136 	return 0;
1137 }
1138 
1139 
1140 static void digi_close(struct usb_serial_port *port)
1141 {
1142 	DEFINE_WAIT(wait);
1143 	int ret;
1144 	unsigned char buf[32];
1145 	struct digi_port *priv = usb_get_serial_port_data(port);
1146 
1147 	mutex_lock(&port->serial->disc_mutex);
1148 	/* if disconnected, just clear flags */
1149 	if (port->serial->disconnected)
1150 		goto exit;
1151 
1152 	if (port->serial->dev) {
1153 		/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1154 		digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1155 
1156 		/* disable input flow control */
1157 		buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1158 		buf[1] = priv->dp_port_num;
1159 		buf[2] = DIGI_DISABLE;
1160 		buf[3] = 0;
1161 
1162 		/* disable output flow control */
1163 		buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1164 		buf[5] = priv->dp_port_num;
1165 		buf[6] = DIGI_DISABLE;
1166 		buf[7] = 0;
1167 
1168 		/* disable reading modem signals automatically */
1169 		buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1170 		buf[9] = priv->dp_port_num;
1171 		buf[10] = DIGI_DISABLE;
1172 		buf[11] = 0;
1173 
1174 		/* disable receive */
1175 		buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1176 		buf[13] = priv->dp_port_num;
1177 		buf[14] = DIGI_DISABLE;
1178 		buf[15] = 0;
1179 
1180 		/* flush fifos */
1181 		buf[16] = DIGI_CMD_IFLUSH_FIFO;
1182 		buf[17] = priv->dp_port_num;
1183 		buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1184 		buf[19] = 0;
1185 
1186 		ret = digi_write_oob_command(port, buf, 20, 0);
1187 		if (ret != 0)
1188 			dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n", ret);
1189 
1190 		/* wait for final commands on oob port to complete */
1191 		prepare_to_wait(&priv->dp_flush_wait, &wait,
1192 							TASK_INTERRUPTIBLE);
1193 		schedule_timeout(DIGI_CLOSE_TIMEOUT);
1194 		finish_wait(&priv->dp_flush_wait, &wait);
1195 
1196 		/* shutdown any outstanding bulk writes */
1197 		usb_kill_urb(port->write_urb);
1198 	}
1199 exit:
1200 	spin_lock_irq(&priv->dp_port_lock);
1201 	priv->dp_write_urb_in_use = 0;
1202 	wake_up_interruptible(&priv->dp_close_wait);
1203 	spin_unlock_irq(&priv->dp_port_lock);
1204 	mutex_unlock(&port->serial->disc_mutex);
1205 }
1206 
1207 
1208 /*
1209  *  Digi Startup Device
1210  *
1211  *  Starts reads on all ports.  Must be called AFTER startup, with
1212  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1213  */
1214 
1215 static int digi_startup_device(struct usb_serial *serial)
1216 {
1217 	int i, ret = 0;
1218 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1219 	struct usb_serial_port *port;
1220 
1221 	/* be sure this happens exactly once */
1222 	spin_lock(&serial_priv->ds_serial_lock);
1223 	if (serial_priv->ds_device_started) {
1224 		spin_unlock(&serial_priv->ds_serial_lock);
1225 		return 0;
1226 	}
1227 	serial_priv->ds_device_started = 1;
1228 	spin_unlock(&serial_priv->ds_serial_lock);
1229 
1230 	/* start reading from each bulk in endpoint for the device */
1231 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1232 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1233 		port = serial->port[i];
1234 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1235 		if (ret != 0) {
1236 			dev_err(&port->dev,
1237 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1238 				__func__, ret, i);
1239 			break;
1240 		}
1241 	}
1242 	return ret;
1243 }
1244 
1245 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1246 {
1247 	struct digi_port *priv;
1248 
1249 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1250 	if (!priv)
1251 		return -ENOMEM;
1252 
1253 	spin_lock_init(&priv->dp_port_lock);
1254 	priv->dp_port_num = port_num;
1255 	init_waitqueue_head(&priv->dp_modem_change_wait);
1256 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1257 	init_waitqueue_head(&priv->dp_flush_wait);
1258 	init_waitqueue_head(&priv->dp_close_wait);
1259 	INIT_WORK(&priv->dp_wakeup_work, digi_wakeup_write_lock);
1260 	priv->dp_port = port;
1261 
1262 	init_waitqueue_head(&port->write_wait);
1263 
1264 	usb_set_serial_port_data(port, priv);
1265 
1266 	return 0;
1267 }
1268 
1269 static int digi_startup(struct usb_serial *serial)
1270 {
1271 	struct digi_serial *serial_priv;
1272 	int ret;
1273 
1274 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1275 	if (!serial_priv)
1276 		return -ENOMEM;
1277 
1278 	spin_lock_init(&serial_priv->ds_serial_lock);
1279 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1280 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1281 
1282 	ret = digi_port_init(serial_priv->ds_oob_port,
1283 						serial_priv->ds_oob_port_num);
1284 	if (ret) {
1285 		kfree(serial_priv);
1286 		return ret;
1287 	}
1288 
1289 	usb_set_serial_data(serial, serial_priv);
1290 
1291 	return 0;
1292 }
1293 
1294 
1295 static void digi_disconnect(struct usb_serial *serial)
1296 {
1297 	int i;
1298 
1299 	/* stop reads and writes on all ports */
1300 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1301 		usb_kill_urb(serial->port[i]->read_urb);
1302 		usb_kill_urb(serial->port[i]->write_urb);
1303 	}
1304 }
1305 
1306 
1307 static void digi_release(struct usb_serial *serial)
1308 {
1309 	struct digi_serial *serial_priv;
1310 	struct digi_port *priv;
1311 
1312 	serial_priv = usb_get_serial_data(serial);
1313 
1314 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1315 	kfree(priv);
1316 
1317 	kfree(serial_priv);
1318 }
1319 
1320 static int digi_port_probe(struct usb_serial_port *port)
1321 {
1322 	unsigned port_num;
1323 
1324 	port_num = port->number - port->serial->minor;
1325 
1326 	return digi_port_init(port, port_num);
1327 }
1328 
1329 static int digi_port_remove(struct usb_serial_port *port)
1330 {
1331 	struct digi_port *priv;
1332 
1333 	priv = usb_get_serial_port_data(port);
1334 	kfree(priv);
1335 
1336 	return 0;
1337 }
1338 
1339 static void digi_read_bulk_callback(struct urb *urb)
1340 {
1341 	struct usb_serial_port *port = urb->context;
1342 	struct digi_port *priv;
1343 	struct digi_serial *serial_priv;
1344 	int ret;
1345 	int status = urb->status;
1346 
1347 	/* port sanity check, do not resubmit if port is not valid */
1348 	if (port == NULL)
1349 		return;
1350 	priv = usb_get_serial_port_data(port);
1351 	if (priv == NULL) {
1352 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1353 			__func__, status);
1354 		return;
1355 	}
1356 	if (port->serial == NULL ||
1357 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1358 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1359 			"is NULL, status=%d\n", __func__, status);
1360 		return;
1361 	}
1362 
1363 	/* do not resubmit urb if it has any status error */
1364 	if (status) {
1365 		dev_err(&port->dev,
1366 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1367 			__func__, status, priv->dp_port_num);
1368 		return;
1369 	}
1370 
1371 	/* handle oob or inb callback, do not resubmit if error */
1372 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1373 		if (digi_read_oob_callback(urb) != 0)
1374 			return;
1375 	} else {
1376 		if (digi_read_inb_callback(urb) != 0)
1377 			return;
1378 	}
1379 
1380 	/* continue read */
1381 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1382 	if (ret != 0 && ret != -EPERM) {
1383 		dev_err(&port->dev,
1384 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1385 			__func__, ret, priv->dp_port_num);
1386 	}
1387 
1388 }
1389 
1390 /*
1391  *  Digi Read INB Callback
1392  *
1393  *  Digi Read INB Callback handles reads on the in band ports, sending
1394  *  the data on to the tty subsystem.  When called we know port and
1395  *  port->private are not NULL and port->serial has been validated.
1396  *  It returns 0 if successful, 1 if successful but the port is
1397  *  throttled, and -1 if the sanity checks failed.
1398  */
1399 
1400 static int digi_read_inb_callback(struct urb *urb)
1401 {
1402 
1403 	struct usb_serial_port *port = urb->context;
1404 	struct tty_struct *tty;
1405 	struct digi_port *priv = usb_get_serial_port_data(port);
1406 	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
1407 	int len = ((unsigned char *)urb->transfer_buffer)[1];
1408 	int port_status = ((unsigned char *)urb->transfer_buffer)[2];
1409 	unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
1410 	int flag, throttled;
1411 	int status = urb->status;
1412 
1413 	/* do not process callbacks on closed ports */
1414 	/* but do continue the read chain */
1415 	if (urb->status == -ENOENT)
1416 		return 0;
1417 
1418 	/* short/multiple packet check */
1419 	if (urb->actual_length != len + 2) {
1420 		dev_err(&port->dev, "%s: INCOMPLETE OR MULTIPLE PACKET, "
1421 			"status=%d, port=%d, opcode=%d, len=%d, "
1422 			"actual_length=%d, status=%d\n", __func__, status,
1423 			priv->dp_port_num, opcode, len, urb->actual_length,
1424 			port_status);
1425 		return -1;
1426 	}
1427 
1428 	tty = tty_port_tty_get(&port->port);
1429 	spin_lock(&priv->dp_port_lock);
1430 
1431 	/* check for throttle; if set, do not resubmit read urb */
1432 	/* indicate the read chain needs to be restarted on unthrottle */
1433 	throttled = priv->dp_throttled;
1434 	if (throttled)
1435 		priv->dp_throttle_restart = 1;
1436 
1437 	/* receive data */
1438 	if (tty && opcode == DIGI_CMD_RECEIVE_DATA) {
1439 		/* get flag from port_status */
1440 		flag = 0;
1441 
1442 		/* overrun is special, not associated with a char */
1443 		if (port_status & DIGI_OVERRUN_ERROR)
1444 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1445 
1446 		/* break takes precedence over parity, */
1447 		/* which takes precedence over framing errors */
1448 		if (port_status & DIGI_BREAK_ERROR)
1449 			flag = TTY_BREAK;
1450 		else if (port_status & DIGI_PARITY_ERROR)
1451 			flag = TTY_PARITY;
1452 		else if (port_status & DIGI_FRAMING_ERROR)
1453 			flag = TTY_FRAME;
1454 
1455 		/* data length is len-1 (one byte of len is port_status) */
1456 		--len;
1457 		if (len > 0) {
1458 			tty_insert_flip_string_fixed_flag(tty, data, flag,
1459 									len);
1460 			tty_flip_buffer_push(tty);
1461 		}
1462 	}
1463 	spin_unlock(&priv->dp_port_lock);
1464 	tty_kref_put(tty);
1465 
1466 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1467 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1468 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1469 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1470 
1471 	return throttled ? 1 : 0;
1472 
1473 }
1474 
1475 
1476 /*
1477  *  Digi Read OOB Callback
1478  *
1479  *  Digi Read OOB Callback handles reads on the out of band port.
1480  *  When called we know port and port->private are not NULL and
1481  *  the port->serial is valid.  It returns 0 if successful, and
1482  *  -1 if the sanity checks failed.
1483  */
1484 
1485 static int digi_read_oob_callback(struct urb *urb)
1486 {
1487 
1488 	struct usb_serial_port *port = urb->context;
1489 	struct usb_serial *serial = port->serial;
1490 	struct tty_struct *tty;
1491 	struct digi_port *priv = usb_get_serial_port_data(port);
1492 	int opcode, line, status, val;
1493 	int i;
1494 	unsigned int rts;
1495 
1496 	/* handle each oob command */
1497 	for (i = 0; i < urb->actual_length - 3;) {
1498 		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
1499 		line = ((unsigned char *)urb->transfer_buffer)[i++];
1500 		status = ((unsigned char *)urb->transfer_buffer)[i++];
1501 		val = ((unsigned char *)urb->transfer_buffer)[i++];
1502 
1503 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1504 			opcode, line, status, val);
1505 
1506 		if (status != 0 || line >= serial->type->num_ports)
1507 			continue;
1508 
1509 		port = serial->port[line];
1510 
1511 		priv = usb_get_serial_port_data(port);
1512 		if (priv == NULL)
1513 			return -1;
1514 
1515 		tty = tty_port_tty_get(&port->port);
1516 
1517 		rts = 0;
1518 		if (tty)
1519 			rts = tty->termios.c_cflag & CRTSCTS;
1520 
1521 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1522 			spin_lock(&priv->dp_port_lock);
1523 			/* convert from digi flags to termiox flags */
1524 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1525 				priv->dp_modem_signals |= TIOCM_CTS;
1526 				/* port must be open to use tty struct */
1527 				if (rts) {
1528 					tty->hw_stopped = 0;
1529 					digi_wakeup_write(port);
1530 				}
1531 			} else {
1532 				priv->dp_modem_signals &= ~TIOCM_CTS;
1533 				/* port must be open to use tty struct */
1534 				if (rts)
1535 					tty->hw_stopped = 1;
1536 			}
1537 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1538 				priv->dp_modem_signals |= TIOCM_DSR;
1539 			else
1540 				priv->dp_modem_signals &= ~TIOCM_DSR;
1541 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1542 				priv->dp_modem_signals |= TIOCM_RI;
1543 			else
1544 				priv->dp_modem_signals &= ~TIOCM_RI;
1545 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1546 				priv->dp_modem_signals |= TIOCM_CD;
1547 			else
1548 				priv->dp_modem_signals &= ~TIOCM_CD;
1549 
1550 			wake_up_interruptible(&priv->dp_modem_change_wait);
1551 			spin_unlock(&priv->dp_port_lock);
1552 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1553 			spin_lock(&priv->dp_port_lock);
1554 			priv->dp_transmit_idle = 1;
1555 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1556 			spin_unlock(&priv->dp_port_lock);
1557 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1558 			wake_up_interruptible(&priv->dp_flush_wait);
1559 		}
1560 		tty_kref_put(tty);
1561 	}
1562 	return 0;
1563 
1564 }
1565 
1566 module_usb_serial_driver(serial_drivers, id_table_combined);
1567 
1568 MODULE_AUTHOR(DRIVER_AUTHOR);
1569 MODULE_DESCRIPTION(DRIVER_DESC);
1570 MODULE_LICENSE("GPL");
1571