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 void digi_read_bulk_callback(struct urb *urb);
248 static int digi_read_inb_callback(struct urb *urb);
249 static int digi_read_oob_callback(struct urb *urb);
250 
251 
252 /* Statics */
253 
254 static bool debug;
255 
256 static const struct usb_device_id id_table_combined[] = {
257 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
258 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
259 	{ }						/* Terminating entry */
260 };
261 
262 static const struct usb_device_id id_table_2[] = {
263 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
264 	{ }						/* Terminating entry */
265 };
266 
267 static const struct usb_device_id id_table_4[] = {
268 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
269 	{ }						/* Terminating entry */
270 };
271 
272 MODULE_DEVICE_TABLE(usb, id_table_combined);
273 
274 static struct usb_driver digi_driver = {
275 	.name =		"digi_acceleport",
276 	.probe =	usb_serial_probe,
277 	.disconnect =	usb_serial_disconnect,
278 	.id_table =	id_table_combined,
279 };
280 
281 
282 /* device info needed for the Digi serial converter */
283 
284 static struct usb_serial_driver digi_acceleport_2_device = {
285 	.driver = {
286 		.owner =		THIS_MODULE,
287 		.name =			"digi_2",
288 	},
289 	.description =			"Digi 2 port USB adapter",
290 	.id_table =			id_table_2,
291 	.num_ports =			3,
292 	.open =				digi_open,
293 	.close =			digi_close,
294 	.dtr_rts =			digi_dtr_rts,
295 	.write =			digi_write,
296 	.write_room =			digi_write_room,
297 	.write_bulk_callback = 		digi_write_bulk_callback,
298 	.read_bulk_callback =		digi_read_bulk_callback,
299 	.chars_in_buffer =		digi_chars_in_buffer,
300 	.throttle =			digi_rx_throttle,
301 	.unthrottle =			digi_rx_unthrottle,
302 	.set_termios =			digi_set_termios,
303 	.break_ctl =			digi_break_ctl,
304 	.tiocmget =			digi_tiocmget,
305 	.tiocmset =			digi_tiocmset,
306 	.attach =			digi_startup,
307 	.disconnect =			digi_disconnect,
308 	.release =			digi_release,
309 };
310 
311 static struct usb_serial_driver digi_acceleport_4_device = {
312 	.driver = {
313 		.owner =		THIS_MODULE,
314 		.name =			"digi_4",
315 	},
316 	.description =			"Digi 4 port USB adapter",
317 	.id_table =			id_table_4,
318 	.num_ports =			4,
319 	.open =				digi_open,
320 	.close =			digi_close,
321 	.write =			digi_write,
322 	.write_room =			digi_write_room,
323 	.write_bulk_callback = 		digi_write_bulk_callback,
324 	.read_bulk_callback =		digi_read_bulk_callback,
325 	.chars_in_buffer =		digi_chars_in_buffer,
326 	.throttle =			digi_rx_throttle,
327 	.unthrottle =			digi_rx_unthrottle,
328 	.set_termios =			digi_set_termios,
329 	.break_ctl =			digi_break_ctl,
330 	.tiocmget =			digi_tiocmget,
331 	.tiocmset =			digi_tiocmset,
332 	.attach =			digi_startup,
333 	.disconnect =			digi_disconnect,
334 	.release =			digi_release,
335 };
336 
337 static struct usb_serial_driver * const serial_drivers[] = {
338 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
339 };
340 
341 /* Functions */
342 
343 /*
344  *  Cond Wait Interruptible Timeout Irqrestore
345  *
346  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
347  *  so that wake ups are not lost if they occur between the unlock
348  *  and the sleep.  In other words, spin_unlock_irqrestore and
349  *  interruptible_sleep_on_timeout are "atomic" with respect to
350  *  wake ups.  This is used to implement condition variables.
351  *
352  *  interruptible_sleep_on_timeout is deprecated and has been replaced
353  *  with the equivalent code.
354  */
355 
356 static long cond_wait_interruptible_timeout_irqrestore(
357 	wait_queue_head_t *q, long timeout,
358 	spinlock_t *lock, unsigned long flags)
359 __releases(lock)
360 {
361 	DEFINE_WAIT(wait);
362 
363 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
364 	spin_unlock_irqrestore(lock, flags);
365 	timeout = schedule_timeout(timeout);
366 	finish_wait(q, &wait);
367 
368 	return timeout;
369 }
370 
371 
372 /*
373  *  Digi Wakeup Write
374  *
375  *  Wake up port, line discipline, and tty processes sleeping
376  *  on writes.
377  */
378 
379 static void digi_wakeup_write_lock(struct work_struct *work)
380 {
381 	struct digi_port *priv =
382 			container_of(work, struct digi_port, dp_wakeup_work);
383 	struct usb_serial_port *port = priv->dp_port;
384 	unsigned long flags;
385 
386 	spin_lock_irqsave(&priv->dp_port_lock, flags);
387 	digi_wakeup_write(port);
388 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
389 }
390 
391 static void digi_wakeup_write(struct usb_serial_port *port)
392 {
393 	struct tty_struct *tty = tty_port_tty_get(&port->port);
394 	if (tty) {
395 		tty_wakeup(tty);
396 		tty_kref_put(tty);
397 	}
398 }
399 
400 
401 /*
402  *  Digi Write OOB Command
403  *
404  *  Write commands on the out of band port.  Commands are 4
405  *  bytes each, multiple commands can be sent at once, and
406  *  no command will be split across USB packets.  Returns 0
407  *  if successful, -EINTR if interrupted while sleeping and
408  *  the interruptible flag is true, or a negative error
409  *  returned by usb_submit_urb.
410  */
411 
412 static int digi_write_oob_command(struct usb_serial_port *port,
413 	unsigned char *buf, int count, int interruptible)
414 {
415 
416 	int ret = 0;
417 	int len;
418 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
419 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
420 	unsigned long flags = 0;
421 
422 	dbg("digi_write_oob_command: TOP: port=%d, count=%d", oob_priv->dp_port_num, count);
423 
424 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
425 	while (count > 0) {
426 		while (oob_priv->dp_write_urb_in_use) {
427 			cond_wait_interruptible_timeout_irqrestore(
428 				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
429 				&oob_priv->dp_port_lock, flags);
430 			if (interruptible && signal_pending(current))
431 				return -EINTR;
432 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
433 		}
434 
435 		/* len must be a multiple of 4, so commands are not split */
436 		len = min(count, oob_port->bulk_out_size);
437 		if (len > 4)
438 			len &= ~3;
439 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
440 		oob_port->write_urb->transfer_buffer_length = len;
441 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
442 		if (ret == 0) {
443 			oob_priv->dp_write_urb_in_use = 1;
444 			count -= len;
445 			buf += len;
446 		}
447 	}
448 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
449 	if (ret)
450 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
451 			__func__, ret);
452 	return ret;
453 
454 }
455 
456 
457 /*
458  *  Digi Write In Band Command
459  *
460  *  Write commands on the given port.  Commands are 4
461  *  bytes each, multiple commands can be sent at once, and
462  *  no command will be split across USB packets.  If timeout
463  *  is non-zero, write in band command will return after
464  *  waiting unsuccessfully for the URB status to clear for
465  *  timeout ticks.  Returns 0 if successful, or a negative
466  *  error returned by digi_write.
467  */
468 
469 static int digi_write_inb_command(struct usb_serial_port *port,
470 	unsigned char *buf, int count, unsigned long timeout)
471 {
472 	int ret = 0;
473 	int len;
474 	struct digi_port *priv = usb_get_serial_port_data(port);
475 	unsigned char *data = port->write_urb->transfer_buffer;
476 	unsigned long flags = 0;
477 
478 	dbg("digi_write_inb_command: TOP: port=%d, count=%d",
479 		priv->dp_port_num, count);
480 
481 	if (timeout)
482 		timeout += jiffies;
483 	else
484 		timeout = ULONG_MAX;
485 
486 	spin_lock_irqsave(&priv->dp_port_lock, flags);
487 	while (count > 0 && ret == 0) {
488 		while (priv->dp_write_urb_in_use &&
489 		       time_before(jiffies, timeout)) {
490 			cond_wait_interruptible_timeout_irqrestore(
491 				&port->write_wait, DIGI_RETRY_TIMEOUT,
492 				&priv->dp_port_lock, flags);
493 			if (signal_pending(current))
494 				return -EINTR;
495 			spin_lock_irqsave(&priv->dp_port_lock, flags);
496 		}
497 
498 		/* len must be a multiple of 4 and small enough to */
499 		/* guarantee the write will send buffered data first, */
500 		/* so commands are in order with data and not split */
501 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
502 		if (len > 4)
503 			len &= ~3;
504 
505 		/* write any buffered data first */
506 		if (priv->dp_out_buf_len > 0) {
507 			data[0] = DIGI_CMD_SEND_DATA;
508 			data[1] = priv->dp_out_buf_len;
509 			memcpy(data + 2, priv->dp_out_buf,
510 				priv->dp_out_buf_len);
511 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
512 			port->write_urb->transfer_buffer_length
513 				= priv->dp_out_buf_len + 2 + len;
514 		} else {
515 			memcpy(data, buf, len);
516 			port->write_urb->transfer_buffer_length = len;
517 		}
518 
519 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
520 		if (ret == 0) {
521 			priv->dp_write_urb_in_use = 1;
522 			priv->dp_out_buf_len = 0;
523 			count -= len;
524 			buf += len;
525 		}
526 
527 	}
528 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
529 
530 	if (ret)
531 		dev_err(&port->dev,
532 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
533 			__func__, ret, priv->dp_port_num);
534 	return ret;
535 }
536 
537 
538 /*
539  *  Digi Set Modem Signals
540  *
541  *  Sets or clears DTR and RTS on the port, according to the
542  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
543  *  for the modem_signals argument.  Returns 0 if successful,
544  *  -EINTR if interrupted while sleeping, or a non-zero error
545  *  returned by usb_submit_urb.
546  */
547 
548 static int digi_set_modem_signals(struct usb_serial_port *port,
549 	unsigned int modem_signals, int interruptible)
550 {
551 
552 	int ret;
553 	struct digi_port *port_priv = usb_get_serial_port_data(port);
554 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
555 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
556 	unsigned char *data = oob_port->write_urb->transfer_buffer;
557 	unsigned long flags = 0;
558 
559 
560 	dbg("digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x",
561 		port_priv->dp_port_num, modem_signals);
562 
563 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
564 	spin_lock(&port_priv->dp_port_lock);
565 
566 	while (oob_priv->dp_write_urb_in_use) {
567 		spin_unlock(&port_priv->dp_port_lock);
568 		cond_wait_interruptible_timeout_irqrestore(
569 			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
570 			&oob_priv->dp_port_lock, flags);
571 		if (interruptible && signal_pending(current))
572 			return -EINTR;
573 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
574 		spin_lock(&port_priv->dp_port_lock);
575 	}
576 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
577 	data[1] = port_priv->dp_port_num;
578 	data[2] = (modem_signals & TIOCM_DTR) ?
579 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
580 	data[3] = 0;
581 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
582 	data[5] = port_priv->dp_port_num;
583 	data[6] = (modem_signals & TIOCM_RTS) ?
584 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
585 	data[7] = 0;
586 
587 	oob_port->write_urb->transfer_buffer_length = 8;
588 
589 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
590 	if (ret == 0) {
591 		oob_priv->dp_write_urb_in_use = 1;
592 		port_priv->dp_modem_signals =
593 			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
594 			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
595 	}
596 	spin_unlock(&port_priv->dp_port_lock);
597 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
598 	if (ret)
599 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
600 			__func__, ret);
601 	return ret;
602 }
603 
604 /*
605  *  Digi Transmit Idle
606  *
607  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
608  *  to go idle.  It returns 0 if successful or a negative error.
609  *
610  *  There are race conditions here if more than one process is calling
611  *  digi_transmit_idle on the same port at the same time.  However, this
612  *  is only called from close, and only one process can be in close on a
613  *  port at a time, so its ok.
614  */
615 
616 static int digi_transmit_idle(struct usb_serial_port *port,
617 	unsigned long timeout)
618 {
619 	int ret;
620 	unsigned char buf[2];
621 	struct digi_port *priv = usb_get_serial_port_data(port);
622 	unsigned long flags = 0;
623 
624 	spin_lock_irqsave(&priv->dp_port_lock, flags);
625 	priv->dp_transmit_idle = 0;
626 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
627 
628 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
629 	buf[1] = 0;
630 
631 	timeout += jiffies;
632 
633 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
634 	if (ret != 0)
635 		return ret;
636 
637 	spin_lock_irqsave(&priv->dp_port_lock, flags);
638 
639 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
640 		cond_wait_interruptible_timeout_irqrestore(
641 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
642 			&priv->dp_port_lock, flags);
643 		if (signal_pending(current))
644 			return -EINTR;
645 		spin_lock_irqsave(&priv->dp_port_lock, flags);
646 	}
647 	priv->dp_transmit_idle = 0;
648 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
649 	return 0;
650 
651 }
652 
653 
654 static void digi_rx_throttle(struct tty_struct *tty)
655 {
656 	unsigned long flags;
657 	struct usb_serial_port *port = tty->driver_data;
658 	struct digi_port *priv = usb_get_serial_port_data(port);
659 
660 
661 	dbg("digi_rx_throttle: TOP: port=%d", priv->dp_port_num);
662 
663 	/* stop receiving characters by not resubmitting the read urb */
664 	spin_lock_irqsave(&priv->dp_port_lock, flags);
665 	priv->dp_throttled = 1;
666 	priv->dp_throttle_restart = 0;
667 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
668 }
669 
670 
671 static void digi_rx_unthrottle(struct tty_struct *tty)
672 {
673 	int ret = 0;
674 	unsigned long flags;
675 	struct usb_serial_port *port = tty->driver_data;
676 	struct digi_port *priv = usb_get_serial_port_data(port);
677 
678 	dbg("digi_rx_unthrottle: TOP: port=%d", priv->dp_port_num);
679 
680 	spin_lock_irqsave(&priv->dp_port_lock, flags);
681 
682 	/* restart read chain */
683 	if (priv->dp_throttle_restart)
684 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
685 
686 	/* turn throttle off */
687 	priv->dp_throttled = 0;
688 	priv->dp_throttle_restart = 0;
689 
690 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
691 
692 	if (ret)
693 		dev_err(&port->dev,
694 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
695 			__func__, ret, priv->dp_port_num);
696 }
697 
698 
699 static void digi_set_termios(struct tty_struct *tty,
700 		struct usb_serial_port *port, struct ktermios *old_termios)
701 {
702 	struct digi_port *priv = usb_get_serial_port_data(port);
703 	unsigned int iflag = tty->termios->c_iflag;
704 	unsigned int cflag = tty->termios->c_cflag;
705 	unsigned int old_iflag = old_termios->c_iflag;
706 	unsigned int old_cflag = old_termios->c_cflag;
707 	unsigned char buf[32];
708 	unsigned int modem_signals;
709 	int arg, ret;
710 	int i = 0;
711 	speed_t baud;
712 
713 	dbg("digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x", priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
714 
715 	/* set baud rate */
716 	baud = tty_get_baud_rate(tty);
717 	if (baud != tty_termios_baud_rate(old_termios)) {
718 		arg = -1;
719 
720 		/* reassert DTR and (maybe) RTS on transition from B0 */
721 		if ((old_cflag&CBAUD) == B0) {
722 			/* don't set RTS if using hardware flow control */
723 			/* and throttling input */
724 			modem_signals = TIOCM_DTR;
725 			if (!(tty->termios->c_cflag & CRTSCTS) ||
726 			    !test_bit(TTY_THROTTLED, &tty->flags))
727 				modem_signals |= TIOCM_RTS;
728 			digi_set_modem_signals(port, modem_signals, 1);
729 		}
730 		switch (baud) {
731 		/* drop DTR and RTS on transition to B0 */
732 		case 0: digi_set_modem_signals(port, 0, 1); break;
733 		case 50: arg = DIGI_BAUD_50; break;
734 		case 75: arg = DIGI_BAUD_75; break;
735 		case 110: arg = DIGI_BAUD_110; break;
736 		case 150: arg = DIGI_BAUD_150; break;
737 		case 200: arg = DIGI_BAUD_200; break;
738 		case 300: arg = DIGI_BAUD_300; break;
739 		case 600: arg = DIGI_BAUD_600; break;
740 		case 1200: arg = DIGI_BAUD_1200; break;
741 		case 1800: arg = DIGI_BAUD_1800; break;
742 		case 2400: arg = DIGI_BAUD_2400; break;
743 		case 4800: arg = DIGI_BAUD_4800; break;
744 		case 9600: arg = DIGI_BAUD_9600; break;
745 		case 19200: arg = DIGI_BAUD_19200; break;
746 		case 38400: arg = DIGI_BAUD_38400; break;
747 		case 57600: arg = DIGI_BAUD_57600; break;
748 		case 115200: arg = DIGI_BAUD_115200; break;
749 		case 230400: arg = DIGI_BAUD_230400; break;
750 		case 460800: arg = DIGI_BAUD_460800; break;
751 		default:
752 			arg = DIGI_BAUD_9600;
753 			baud = 9600;
754 			break;
755 		}
756 		if (arg != -1) {
757 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
758 			buf[i++] = priv->dp_port_num;
759 			buf[i++] = arg;
760 			buf[i++] = 0;
761 		}
762 	}
763 	/* set parity */
764 	tty->termios->c_cflag &= ~CMSPAR;
765 
766 	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
767 		if (cflag&PARENB) {
768 			if (cflag&PARODD)
769 				arg = DIGI_PARITY_ODD;
770 			else
771 				arg = DIGI_PARITY_EVEN;
772 		} else {
773 			arg = DIGI_PARITY_NONE;
774 		}
775 		buf[i++] = DIGI_CMD_SET_PARITY;
776 		buf[i++] = priv->dp_port_num;
777 		buf[i++] = arg;
778 		buf[i++] = 0;
779 	}
780 	/* set word size */
781 	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
782 		arg = -1;
783 		switch (cflag&CSIZE) {
784 		case CS5: arg = DIGI_WORD_SIZE_5; break;
785 		case CS6: arg = DIGI_WORD_SIZE_6; break;
786 		case CS7: arg = DIGI_WORD_SIZE_7; break;
787 		case CS8: arg = DIGI_WORD_SIZE_8; break;
788 		default:
789 			dbg("digi_set_termios: can't handle word size %d",
790 				(cflag&CSIZE));
791 			break;
792 		}
793 
794 		if (arg != -1) {
795 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
796 			buf[i++] = priv->dp_port_num;
797 			buf[i++] = arg;
798 			buf[i++] = 0;
799 		}
800 
801 	}
802 
803 	/* set stop bits */
804 	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
805 
806 		if ((cflag&CSTOPB))
807 			arg = DIGI_STOP_BITS_2;
808 		else
809 			arg = DIGI_STOP_BITS_1;
810 
811 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
812 		buf[i++] = priv->dp_port_num;
813 		buf[i++] = arg;
814 		buf[i++] = 0;
815 
816 	}
817 
818 	/* set input flow control */
819 	if ((iflag&IXOFF) != (old_iflag&IXOFF)
820 	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
821 		arg = 0;
822 		if (iflag&IXOFF)
823 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
824 		else
825 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
826 
827 		if (cflag&CRTSCTS) {
828 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
829 
830 			/* On USB-4 it is necessary to assert RTS prior */
831 			/* to selecting RTS input flow control.  */
832 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
833 			buf[i++] = priv->dp_port_num;
834 			buf[i++] = DIGI_RTS_ACTIVE;
835 			buf[i++] = 0;
836 
837 		} else {
838 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
839 		}
840 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
841 		buf[i++] = priv->dp_port_num;
842 		buf[i++] = arg;
843 		buf[i++] = 0;
844 	}
845 
846 	/* set output flow control */
847 	if ((iflag & IXON) != (old_iflag & IXON)
848 	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
849 		arg = 0;
850 		if (iflag & IXON)
851 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
852 		else
853 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
854 
855 		if (cflag & CRTSCTS) {
856 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
857 		} else {
858 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
859 			tty->hw_stopped = 0;
860 		}
861 
862 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
863 		buf[i++] = priv->dp_port_num;
864 		buf[i++] = arg;
865 		buf[i++] = 0;
866 	}
867 
868 	/* set receive enable/disable */
869 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
870 		if (cflag & CREAD)
871 			arg = DIGI_ENABLE;
872 		else
873 			arg = DIGI_DISABLE;
874 
875 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
876 		buf[i++] = priv->dp_port_num;
877 		buf[i++] = arg;
878 		buf[i++] = 0;
879 	}
880 	ret = digi_write_oob_command(port, buf, i, 1);
881 	if (ret != 0)
882 		dbg("digi_set_termios: write oob failed, ret=%d", ret);
883 	tty_encode_baud_rate(tty, baud, baud);
884 }
885 
886 
887 static void digi_break_ctl(struct tty_struct *tty, int break_state)
888 {
889 	struct usb_serial_port *port = tty->driver_data;
890 	unsigned char buf[4];
891 
892 	buf[0] = DIGI_CMD_BREAK_CONTROL;
893 	buf[1] = 2;				/* length */
894 	buf[2] = break_state ? 1 : 0;
895 	buf[3] = 0;				/* pad */
896 	digi_write_inb_command(port, buf, 4, 0);
897 }
898 
899 
900 static int digi_tiocmget(struct tty_struct *tty)
901 {
902 	struct usb_serial_port *port = tty->driver_data;
903 	struct digi_port *priv = usb_get_serial_port_data(port);
904 	unsigned int val;
905 	unsigned long flags;
906 
907 	dbg("%s: TOP: port=%d", __func__, priv->dp_port_num);
908 
909 	spin_lock_irqsave(&priv->dp_port_lock, flags);
910 	val = priv->dp_modem_signals;
911 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
912 	return val;
913 }
914 
915 
916 static int digi_tiocmset(struct tty_struct *tty,
917 					unsigned int set, unsigned int clear)
918 {
919 	struct usb_serial_port *port = tty->driver_data;
920 	struct digi_port *priv = usb_get_serial_port_data(port);
921 	unsigned int val;
922 	unsigned long flags;
923 
924 	dbg("%s: TOP: port=%d", __func__, priv->dp_port_num);
925 
926 	spin_lock_irqsave(&priv->dp_port_lock, flags);
927 	val = (priv->dp_modem_signals & ~clear) | set;
928 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
929 	return digi_set_modem_signals(port, val, 1);
930 }
931 
932 
933 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
934 					const unsigned char *buf, int count)
935 {
936 
937 	int ret, data_len, new_len;
938 	struct digi_port *priv = usb_get_serial_port_data(port);
939 	unsigned char *data = port->write_urb->transfer_buffer;
940 	unsigned long flags = 0;
941 
942 	dbg("digi_write: TOP: port=%d, count=%d, in_interrupt=%ld",
943 		priv->dp_port_num, count, in_interrupt());
944 
945 	/* copy user data (which can sleep) before getting spin lock */
946 	count = min(count, port->bulk_out_size-2);
947 	count = min(64, count);
948 
949 	/* be sure only one write proceeds at a time */
950 	/* there are races on the port private buffer */
951 	spin_lock_irqsave(&priv->dp_port_lock, flags);
952 
953 	/* wait for urb status clear to submit another urb */
954 	if (priv->dp_write_urb_in_use) {
955 		/* buffer data if count is 1 (probably put_char) if possible */
956 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
957 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
958 			new_len = 1;
959 		} else {
960 			new_len = 0;
961 		}
962 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
963 		return new_len;
964 	}
965 
966 	/* allow space for any buffered data and for new data, up to */
967 	/* transfer buffer size - 2 (for command and length bytes) */
968 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
969 	data_len = new_len + priv->dp_out_buf_len;
970 
971 	if (data_len == 0) {
972 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
973 		return 0;
974 	}
975 
976 	port->write_urb->transfer_buffer_length = data_len+2;
977 
978 	*data++ = DIGI_CMD_SEND_DATA;
979 	*data++ = data_len;
980 
981 	/* copy in buffered data first */
982 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
983 	data += priv->dp_out_buf_len;
984 
985 	/* copy in new data */
986 	memcpy(data, buf, new_len);
987 
988 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
989 	if (ret == 0) {
990 		priv->dp_write_urb_in_use = 1;
991 		ret = new_len;
992 		priv->dp_out_buf_len = 0;
993 	}
994 
995 	/* return length of new data written, or error */
996 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
997 	if (ret < 0)
998 		dev_err_console(port,
999 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1000 			__func__, ret, priv->dp_port_num);
1001 	dbg("digi_write: returning %d", ret);
1002 	return ret;
1003 
1004 }
1005 
1006 static void digi_write_bulk_callback(struct urb *urb)
1007 {
1008 
1009 	struct usb_serial_port *port = urb->context;
1010 	struct usb_serial *serial;
1011 	struct digi_port *priv;
1012 	struct digi_serial *serial_priv;
1013 	int ret = 0;
1014 	int status = urb->status;
1015 
1016 	dbg("digi_write_bulk_callback: TOP, status=%d", status);
1017 
1018 	/* port and serial sanity check */
1019 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
1020 		pr_err("%s: port or port->private is NULL, status=%d\n",
1021 			__func__, status);
1022 		return;
1023 	}
1024 	serial = port->serial;
1025 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
1026 		dev_err(&port->dev,
1027 			"%s: serial or serial->private is NULL, status=%d\n",
1028 			__func__, status);
1029 		return;
1030 	}
1031 
1032 	/* handle oob callback */
1033 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1034 		dbg("digi_write_bulk_callback: oob callback");
1035 		spin_lock(&priv->dp_port_lock);
1036 		priv->dp_write_urb_in_use = 0;
1037 		wake_up_interruptible(&port->write_wait);
1038 		spin_unlock(&priv->dp_port_lock);
1039 		return;
1040 	}
1041 
1042 	/* try to send any buffered data on this port */
1043 	spin_lock(&priv->dp_port_lock);
1044 	priv->dp_write_urb_in_use = 0;
1045 	if (priv->dp_out_buf_len > 0) {
1046 		*((unsigned char *)(port->write_urb->transfer_buffer))
1047 			= (unsigned char)DIGI_CMD_SEND_DATA;
1048 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1049 			= (unsigned char)priv->dp_out_buf_len;
1050 		port->write_urb->transfer_buffer_length =
1051 						priv->dp_out_buf_len + 2;
1052 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1053 			priv->dp_out_buf_len);
1054 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1055 		if (ret == 0) {
1056 			priv->dp_write_urb_in_use = 1;
1057 			priv->dp_out_buf_len = 0;
1058 		}
1059 	}
1060 	/* wake up processes sleeping on writes immediately */
1061 	digi_wakeup_write(port);
1062 	/* also queue up a wakeup at scheduler time, in case we */
1063 	/* lost the race in write_chan(). */
1064 	schedule_work(&priv->dp_wakeup_work);
1065 
1066 	spin_unlock(&priv->dp_port_lock);
1067 	if (ret && ret != -EPERM)
1068 		dev_err_console(port,
1069 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1070 			__func__, ret, priv->dp_port_num);
1071 }
1072 
1073 static int digi_write_room(struct tty_struct *tty)
1074 {
1075 	struct usb_serial_port *port = tty->driver_data;
1076 	struct digi_port *priv = usb_get_serial_port_data(port);
1077 	int room;
1078 	unsigned long flags = 0;
1079 
1080 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1081 
1082 	if (priv->dp_write_urb_in_use)
1083 		room = 0;
1084 	else
1085 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1086 
1087 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1088 	dbg("digi_write_room: port=%d, room=%d", priv->dp_port_num, room);
1089 	return room;
1090 
1091 }
1092 
1093 static int digi_chars_in_buffer(struct tty_struct *tty)
1094 {
1095 	struct usb_serial_port *port = tty->driver_data;
1096 	struct digi_port *priv = usb_get_serial_port_data(port);
1097 
1098 	if (priv->dp_write_urb_in_use) {
1099 		dbg("digi_chars_in_buffer: port=%d, chars=%d",
1100 			priv->dp_port_num, port->bulk_out_size - 2);
1101 		/* return(port->bulk_out_size - 2); */
1102 		return 256;
1103 	} else {
1104 		dbg("digi_chars_in_buffer: port=%d, chars=%d",
1105 			priv->dp_port_num, priv->dp_out_buf_len);
1106 		return priv->dp_out_buf_len;
1107 	}
1108 
1109 }
1110 
1111 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1112 {
1113 	/* Adjust DTR and RTS */
1114 	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
1115 }
1116 
1117 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1118 {
1119 	int ret;
1120 	unsigned char buf[32];
1121 	struct digi_port *priv = usb_get_serial_port_data(port);
1122 	struct ktermios not_termios;
1123 
1124 	dbg("digi_open: TOP: port=%d", priv->dp_port_num);
1125 
1126 	/* be sure the device is started up */
1127 	if (digi_startup_device(port->serial) != 0)
1128 		return -ENXIO;
1129 
1130 	/* read modem signals automatically whenever they change */
1131 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1132 	buf[1] = priv->dp_port_num;
1133 	buf[2] = DIGI_ENABLE;
1134 	buf[3] = 0;
1135 
1136 	/* flush fifos */
1137 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1138 	buf[5] = priv->dp_port_num;
1139 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1140 	buf[7] = 0;
1141 
1142 	ret = digi_write_oob_command(port, buf, 8, 1);
1143 	if (ret != 0)
1144 		dbg("digi_open: write oob failed, ret=%d", ret);
1145 
1146 	/* set termios settings */
1147 	if (tty) {
1148 		not_termios.c_cflag = ~tty->termios->c_cflag;
1149 		not_termios.c_iflag = ~tty->termios->c_iflag;
1150 		digi_set_termios(tty, port, &not_termios);
1151 	}
1152 	return 0;
1153 }
1154 
1155 
1156 static void digi_close(struct usb_serial_port *port)
1157 {
1158 	DEFINE_WAIT(wait);
1159 	int ret;
1160 	unsigned char buf[32];
1161 	struct digi_port *priv = usb_get_serial_port_data(port);
1162 
1163 	dbg("digi_close: TOP: port=%d", priv->dp_port_num);
1164 
1165 	mutex_lock(&port->serial->disc_mutex);
1166 	/* if disconnected, just clear flags */
1167 	if (port->serial->disconnected)
1168 		goto exit;
1169 
1170 	if (port->serial->dev) {
1171 		/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1172 		digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1173 
1174 		/* disable input flow control */
1175 		buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1176 		buf[1] = priv->dp_port_num;
1177 		buf[2] = DIGI_DISABLE;
1178 		buf[3] = 0;
1179 
1180 		/* disable output flow control */
1181 		buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1182 		buf[5] = priv->dp_port_num;
1183 		buf[6] = DIGI_DISABLE;
1184 		buf[7] = 0;
1185 
1186 		/* disable reading modem signals automatically */
1187 		buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1188 		buf[9] = priv->dp_port_num;
1189 		buf[10] = DIGI_DISABLE;
1190 		buf[11] = 0;
1191 
1192 		/* disable receive */
1193 		buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1194 		buf[13] = priv->dp_port_num;
1195 		buf[14] = DIGI_DISABLE;
1196 		buf[15] = 0;
1197 
1198 		/* flush fifos */
1199 		buf[16] = DIGI_CMD_IFLUSH_FIFO;
1200 		buf[17] = priv->dp_port_num;
1201 		buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1202 		buf[19] = 0;
1203 
1204 		ret = digi_write_oob_command(port, buf, 20, 0);
1205 		if (ret != 0)
1206 			dbg("digi_close: write oob failed, ret=%d", ret);
1207 
1208 		/* wait for final commands on oob port to complete */
1209 		prepare_to_wait(&priv->dp_flush_wait, &wait,
1210 							TASK_INTERRUPTIBLE);
1211 		schedule_timeout(DIGI_CLOSE_TIMEOUT);
1212 		finish_wait(&priv->dp_flush_wait, &wait);
1213 
1214 		/* shutdown any outstanding bulk writes */
1215 		usb_kill_urb(port->write_urb);
1216 	}
1217 exit:
1218 	spin_lock_irq(&priv->dp_port_lock);
1219 	priv->dp_write_urb_in_use = 0;
1220 	wake_up_interruptible(&priv->dp_close_wait);
1221 	spin_unlock_irq(&priv->dp_port_lock);
1222 	mutex_unlock(&port->serial->disc_mutex);
1223 	dbg("digi_close: done");
1224 }
1225 
1226 
1227 /*
1228  *  Digi Startup Device
1229  *
1230  *  Starts reads on all ports.  Must be called AFTER startup, with
1231  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1232  */
1233 
1234 static int digi_startup_device(struct usb_serial *serial)
1235 {
1236 	int i, ret = 0;
1237 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1238 	struct usb_serial_port *port;
1239 
1240 	/* be sure this happens exactly once */
1241 	spin_lock(&serial_priv->ds_serial_lock);
1242 	if (serial_priv->ds_device_started) {
1243 		spin_unlock(&serial_priv->ds_serial_lock);
1244 		return 0;
1245 	}
1246 	serial_priv->ds_device_started = 1;
1247 	spin_unlock(&serial_priv->ds_serial_lock);
1248 
1249 	/* start reading from each bulk in endpoint for the device */
1250 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1251 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1252 		port = serial->port[i];
1253 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1254 		if (ret != 0) {
1255 			dev_err(&port->dev,
1256 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1257 				__func__, ret, i);
1258 			break;
1259 		}
1260 	}
1261 	return ret;
1262 }
1263 
1264 
1265 static int digi_startup(struct usb_serial *serial)
1266 {
1267 
1268 	int i;
1269 	struct digi_port *priv;
1270 	struct digi_serial *serial_priv;
1271 
1272 	dbg("digi_startup: TOP");
1273 
1274 	/* allocate the private data structures for all ports */
1275 	/* number of regular ports + 1 for the out-of-band port */
1276 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1277 		/* allocate port private structure */
1278 		priv = kmalloc(sizeof(struct digi_port), GFP_KERNEL);
1279 		if (priv == NULL) {
1280 			while (--i >= 0)
1281 				kfree(usb_get_serial_port_data(serial->port[i]));
1282 			return 1;			/* error */
1283 		}
1284 
1285 		/* initialize port private structure */
1286 		spin_lock_init(&priv->dp_port_lock);
1287 		priv->dp_port_num = i;
1288 		priv->dp_out_buf_len = 0;
1289 		priv->dp_write_urb_in_use = 0;
1290 		priv->dp_modem_signals = 0;
1291 		init_waitqueue_head(&priv->dp_modem_change_wait);
1292 		priv->dp_transmit_idle = 0;
1293 		init_waitqueue_head(&priv->dp_transmit_idle_wait);
1294 		priv->dp_throttled = 0;
1295 		priv->dp_throttle_restart = 0;
1296 		init_waitqueue_head(&priv->dp_flush_wait);
1297 		init_waitqueue_head(&priv->dp_close_wait);
1298 		INIT_WORK(&priv->dp_wakeup_work, digi_wakeup_write_lock);
1299 		priv->dp_port = serial->port[i];
1300 		/* initialize write wait queue for this port */
1301 		init_waitqueue_head(&serial->port[i]->write_wait);
1302 
1303 		usb_set_serial_port_data(serial->port[i], priv);
1304 	}
1305 
1306 	/* allocate serial private structure */
1307 	serial_priv = kmalloc(sizeof(struct digi_serial), GFP_KERNEL);
1308 	if (serial_priv == NULL) {
1309 		for (i = 0; i < serial->type->num_ports + 1; i++)
1310 			kfree(usb_get_serial_port_data(serial->port[i]));
1311 		return 1;			/* error */
1312 	}
1313 
1314 	/* initialize serial private structure */
1315 	spin_lock_init(&serial_priv->ds_serial_lock);
1316 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1317 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1318 	serial_priv->ds_device_started = 0;
1319 	usb_set_serial_data(serial, serial_priv);
1320 
1321 	return 0;
1322 }
1323 
1324 
1325 static void digi_disconnect(struct usb_serial *serial)
1326 {
1327 	int i;
1328 	dbg("digi_disconnect: TOP, in_interrupt()=%ld", in_interrupt());
1329 
1330 	/* stop reads and writes on all ports */
1331 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1332 		usb_kill_urb(serial->port[i]->read_urb);
1333 		usb_kill_urb(serial->port[i]->write_urb);
1334 	}
1335 }
1336 
1337 
1338 static void digi_release(struct usb_serial *serial)
1339 {
1340 	int i;
1341 	dbg("digi_release: TOP, in_interrupt()=%ld", in_interrupt());
1342 
1343 	/* free the private data structures for all ports */
1344 	/* number of regular ports + 1 for the out-of-band port */
1345 	for (i = 0; i < serial->type->num_ports + 1; i++)
1346 		kfree(usb_get_serial_port_data(serial->port[i]));
1347 	kfree(usb_get_serial_data(serial));
1348 }
1349 
1350 
1351 static void digi_read_bulk_callback(struct urb *urb)
1352 {
1353 	struct usb_serial_port *port = urb->context;
1354 	struct digi_port *priv;
1355 	struct digi_serial *serial_priv;
1356 	int ret;
1357 	int status = urb->status;
1358 
1359 	dbg("digi_read_bulk_callback: TOP");
1360 
1361 	/* port sanity check, do not resubmit if port is not valid */
1362 	if (port == NULL)
1363 		return;
1364 	priv = usb_get_serial_port_data(port);
1365 	if (priv == NULL) {
1366 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1367 			__func__, status);
1368 		return;
1369 	}
1370 	if (port->serial == NULL ||
1371 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1372 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1373 			"is NULL, status=%d\n", __func__, status);
1374 		return;
1375 	}
1376 
1377 	/* do not resubmit urb if it has any status error */
1378 	if (status) {
1379 		dev_err(&port->dev,
1380 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1381 			__func__, status, priv->dp_port_num);
1382 		return;
1383 	}
1384 
1385 	/* handle oob or inb callback, do not resubmit if error */
1386 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1387 		if (digi_read_oob_callback(urb) != 0)
1388 			return;
1389 	} else {
1390 		if (digi_read_inb_callback(urb) != 0)
1391 			return;
1392 	}
1393 
1394 	/* continue read */
1395 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1396 	if (ret != 0 && ret != -EPERM) {
1397 		dev_err(&port->dev,
1398 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1399 			__func__, ret, priv->dp_port_num);
1400 	}
1401 
1402 }
1403 
1404 /*
1405  *  Digi Read INB Callback
1406  *
1407  *  Digi Read INB Callback handles reads on the in band ports, sending
1408  *  the data on to the tty subsystem.  When called we know port and
1409  *  port->private are not NULL and port->serial has been validated.
1410  *  It returns 0 if successful, 1 if successful but the port is
1411  *  throttled, and -1 if the sanity checks failed.
1412  */
1413 
1414 static int digi_read_inb_callback(struct urb *urb)
1415 {
1416 
1417 	struct usb_serial_port *port = urb->context;
1418 	struct tty_struct *tty;
1419 	struct digi_port *priv = usb_get_serial_port_data(port);
1420 	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
1421 	int len = ((unsigned char *)urb->transfer_buffer)[1];
1422 	int port_status = ((unsigned char *)urb->transfer_buffer)[2];
1423 	unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
1424 	int flag, throttled;
1425 	int status = urb->status;
1426 
1427 	/* do not process callbacks on closed ports */
1428 	/* but do continue the read chain */
1429 	if (urb->status == -ENOENT)
1430 		return 0;
1431 
1432 	/* short/multiple packet check */
1433 	if (urb->actual_length != len + 2) {
1434 		dev_err(&port->dev, "%s: INCOMPLETE OR MULTIPLE PACKET, "
1435 			"status=%d, port=%d, opcode=%d, len=%d, "
1436 			"actual_length=%d, status=%d\n", __func__, status,
1437 			priv->dp_port_num, opcode, len, urb->actual_length,
1438 			port_status);
1439 		return -1;
1440 	}
1441 
1442 	tty = tty_port_tty_get(&port->port);
1443 	spin_lock(&priv->dp_port_lock);
1444 
1445 	/* check for throttle; if set, do not resubmit read urb */
1446 	/* indicate the read chain needs to be restarted on unthrottle */
1447 	throttled = priv->dp_throttled;
1448 	if (throttled)
1449 		priv->dp_throttle_restart = 1;
1450 
1451 	/* receive data */
1452 	if (tty && opcode == DIGI_CMD_RECEIVE_DATA) {
1453 		/* get flag from port_status */
1454 		flag = 0;
1455 
1456 		/* overrun is special, not associated with a char */
1457 		if (port_status & DIGI_OVERRUN_ERROR)
1458 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1459 
1460 		/* break takes precedence over parity, */
1461 		/* which takes precedence over framing errors */
1462 		if (port_status & DIGI_BREAK_ERROR)
1463 			flag = TTY_BREAK;
1464 		else if (port_status & DIGI_PARITY_ERROR)
1465 			flag = TTY_PARITY;
1466 		else if (port_status & DIGI_FRAMING_ERROR)
1467 			flag = TTY_FRAME;
1468 
1469 		/* data length is len-1 (one byte of len is port_status) */
1470 		--len;
1471 		if (len > 0) {
1472 			tty_insert_flip_string_fixed_flag(tty, data, flag,
1473 									len);
1474 			tty_flip_buffer_push(tty);
1475 		}
1476 	}
1477 	spin_unlock(&priv->dp_port_lock);
1478 	tty_kref_put(tty);
1479 
1480 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1481 		dbg("%s: got RECEIVE_DISABLE", __func__);
1482 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1483 		dbg("%s: unknown opcode: %d", __func__, opcode);
1484 
1485 	return throttled ? 1 : 0;
1486 
1487 }
1488 
1489 
1490 /*
1491  *  Digi Read OOB Callback
1492  *
1493  *  Digi Read OOB Callback handles reads on the out of band port.
1494  *  When called we know port and port->private are not NULL and
1495  *  the port->serial is valid.  It returns 0 if successful, and
1496  *  -1 if the sanity checks failed.
1497  */
1498 
1499 static int digi_read_oob_callback(struct urb *urb)
1500 {
1501 
1502 	struct usb_serial_port *port = urb->context;
1503 	struct usb_serial *serial = port->serial;
1504 	struct tty_struct *tty;
1505 	struct digi_port *priv = usb_get_serial_port_data(port);
1506 	int opcode, line, status, val;
1507 	int i;
1508 	unsigned int rts;
1509 
1510 	dbg("digi_read_oob_callback: port=%d, len=%d",
1511 			priv->dp_port_num, urb->actual_length);
1512 
1513 	/* handle each oob command */
1514 	for (i = 0; i < urb->actual_length - 3;) {
1515 		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
1516 		line = ((unsigned char *)urb->transfer_buffer)[i++];
1517 		status = ((unsigned char *)urb->transfer_buffer)[i++];
1518 		val = ((unsigned char *)urb->transfer_buffer)[i++];
1519 
1520 		dbg("digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d",
1521 			opcode, line, status, val);
1522 
1523 		if (status != 0 || line >= serial->type->num_ports)
1524 			continue;
1525 
1526 		port = serial->port[line];
1527 
1528 		priv = usb_get_serial_port_data(port);
1529 		if (priv == NULL)
1530 			return -1;
1531 
1532 		tty = tty_port_tty_get(&port->port);
1533 
1534 		rts = 0;
1535 		if (tty)
1536 			rts = tty->termios->c_cflag & CRTSCTS;
1537 
1538 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1539 			spin_lock(&priv->dp_port_lock);
1540 			/* convert from digi flags to termiox flags */
1541 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1542 				priv->dp_modem_signals |= TIOCM_CTS;
1543 				/* port must be open to use tty struct */
1544 				if (rts) {
1545 					tty->hw_stopped = 0;
1546 					digi_wakeup_write(port);
1547 				}
1548 			} else {
1549 				priv->dp_modem_signals &= ~TIOCM_CTS;
1550 				/* port must be open to use tty struct */
1551 				if (rts)
1552 					tty->hw_stopped = 1;
1553 			}
1554 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1555 				priv->dp_modem_signals |= TIOCM_DSR;
1556 			else
1557 				priv->dp_modem_signals &= ~TIOCM_DSR;
1558 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1559 				priv->dp_modem_signals |= TIOCM_RI;
1560 			else
1561 				priv->dp_modem_signals &= ~TIOCM_RI;
1562 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1563 				priv->dp_modem_signals |= TIOCM_CD;
1564 			else
1565 				priv->dp_modem_signals &= ~TIOCM_CD;
1566 
1567 			wake_up_interruptible(&priv->dp_modem_change_wait);
1568 			spin_unlock(&priv->dp_port_lock);
1569 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1570 			spin_lock(&priv->dp_port_lock);
1571 			priv->dp_transmit_idle = 1;
1572 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1573 			spin_unlock(&priv->dp_port_lock);
1574 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1575 			wake_up_interruptible(&priv->dp_flush_wait);
1576 		}
1577 		tty_kref_put(tty);
1578 	}
1579 	return 0;
1580 
1581 }
1582 
1583 module_usb_serial_driver(digi_driver, serial_drivers);
1584 
1585 MODULE_AUTHOR(DRIVER_AUTHOR);
1586 MODULE_DESCRIPTION(DRIVER_DESC);
1587 MODULE_LICENSE("GPL");
1588 
1589 module_param(debug, bool, S_IRUGO | S_IWUSR);
1590 MODULE_PARM_DESC(debug, "Debug enabled or not");
1591