1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 *  Digi AccelePort USB-4 and USB-2 Serial Converters
4 *
5 *  Copyright 2000 by Digi International
6 *
7 *  Shamelessly based on Brian Warner's keyspan_pda.c and Greg Kroah-Hartman's
8 *  usb-serial driver.
9 *
10 *  Peter Berger (pberger@brimson.com)
11 *  Al Borchers (borchers@steinerpoint.com)
12 */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_driver.h>
19 #include <linux/tty_flip.h>
20 #include <linux/module.h>
21 #include <linux/spinlock.h>
22 #include <linux/uaccess.h>
23 #include <linux/usb.h>
24 #include <linux/wait.h>
25 #include <linux/sched/signal.h>
26 #include <linux/usb/serial.h>
27 
28 /* Defines */
29 
30 #define DRIVER_AUTHOR "Peter Berger <pberger@brimson.com>, Al Borchers <borchers@steinerpoint.com>"
31 #define DRIVER_DESC "Digi AccelePort USB-2/USB-4 Serial Converter driver"
32 
33 /* port output buffer length -- must be <= transfer buffer length - 2 */
34 /* so we can be sure to send the full buffer in one urb */
35 #define DIGI_OUT_BUF_SIZE		8
36 
37 /* port input buffer length -- must be >= transfer buffer length - 3 */
38 /* so we can be sure to hold at least one full buffer from one urb */
39 #define DIGI_IN_BUF_SIZE		64
40 
41 /* retry timeout while sleeping */
42 #define DIGI_RETRY_TIMEOUT		(HZ/10)
43 
44 /* timeout while waiting for tty output to drain in close */
45 /* this delay is used twice in close, so the total delay could */
46 /* be twice this value */
47 #define DIGI_CLOSE_TIMEOUT		(5*HZ)
48 
49 
50 /* AccelePort USB Defines */
51 
52 /* ids */
53 #define DIGI_VENDOR_ID			0x05c5
54 #define DIGI_2_ID			0x0002	/* USB-2 */
55 #define DIGI_4_ID			0x0004	/* USB-4 */
56 
57 /* commands
58  * "INB": can be used on the in-band endpoint
59  * "OOB": can be used on the out-of-band endpoint
60  */
61 #define DIGI_CMD_SET_BAUD_RATE			0	/* INB, OOB */
62 #define DIGI_CMD_SET_WORD_SIZE			1	/* INB, OOB */
63 #define DIGI_CMD_SET_PARITY			2	/* INB, OOB */
64 #define DIGI_CMD_SET_STOP_BITS			3	/* INB, OOB */
65 #define DIGI_CMD_SET_INPUT_FLOW_CONTROL		4	/* INB, OOB */
66 #define DIGI_CMD_SET_OUTPUT_FLOW_CONTROL	5	/* INB, OOB */
67 #define DIGI_CMD_SET_DTR_SIGNAL			6	/* INB, OOB */
68 #define DIGI_CMD_SET_RTS_SIGNAL			7	/* INB, OOB */
69 #define DIGI_CMD_READ_INPUT_SIGNALS		8	/*      OOB */
70 #define DIGI_CMD_IFLUSH_FIFO			9	/*      OOB */
71 #define DIGI_CMD_RECEIVE_ENABLE			10	/* INB, OOB */
72 #define DIGI_CMD_BREAK_CONTROL			11	/* INB, OOB */
73 #define DIGI_CMD_LOCAL_LOOPBACK			12	/* INB, OOB */
74 #define DIGI_CMD_TRANSMIT_IDLE			13	/* INB, OOB */
75 #define DIGI_CMD_READ_UART_REGISTER		14	/*      OOB */
76 #define DIGI_CMD_WRITE_UART_REGISTER		15	/* INB, OOB */
77 #define DIGI_CMD_AND_UART_REGISTER		16	/* INB, OOB */
78 #define DIGI_CMD_OR_UART_REGISTER		17	/* INB, OOB */
79 #define DIGI_CMD_SEND_DATA			18	/* INB      */
80 #define DIGI_CMD_RECEIVE_DATA			19	/* INB      */
81 #define DIGI_CMD_RECEIVE_DISABLE		20	/* INB      */
82 #define DIGI_CMD_GET_PORT_TYPE			21	/*      OOB */
83 
84 /* baud rates */
85 #define DIGI_BAUD_50				0
86 #define DIGI_BAUD_75				1
87 #define DIGI_BAUD_110				2
88 #define DIGI_BAUD_150				3
89 #define DIGI_BAUD_200				4
90 #define DIGI_BAUD_300				5
91 #define DIGI_BAUD_600				6
92 #define DIGI_BAUD_1200				7
93 #define DIGI_BAUD_1800				8
94 #define DIGI_BAUD_2400				9
95 #define DIGI_BAUD_4800				10
96 #define DIGI_BAUD_7200				11
97 #define DIGI_BAUD_9600				12
98 #define DIGI_BAUD_14400				13
99 #define DIGI_BAUD_19200				14
100 #define DIGI_BAUD_28800				15
101 #define DIGI_BAUD_38400				16
102 #define DIGI_BAUD_57600				17
103 #define DIGI_BAUD_76800				18
104 #define DIGI_BAUD_115200			19
105 #define DIGI_BAUD_153600			20
106 #define DIGI_BAUD_230400			21
107 #define DIGI_BAUD_460800			22
108 
109 /* arguments */
110 #define DIGI_WORD_SIZE_5			0
111 #define DIGI_WORD_SIZE_6			1
112 #define DIGI_WORD_SIZE_7			2
113 #define DIGI_WORD_SIZE_8			3
114 
115 #define DIGI_PARITY_NONE			0
116 #define DIGI_PARITY_ODD				1
117 #define DIGI_PARITY_EVEN			2
118 #define DIGI_PARITY_MARK			3
119 #define DIGI_PARITY_SPACE			4
120 
121 #define DIGI_STOP_BITS_1			0
122 #define DIGI_STOP_BITS_2			1
123 
124 #define DIGI_INPUT_FLOW_CONTROL_XON_XOFF	1
125 #define DIGI_INPUT_FLOW_CONTROL_RTS		2
126 #define DIGI_INPUT_FLOW_CONTROL_DTR		4
127 
128 #define DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF	1
129 #define DIGI_OUTPUT_FLOW_CONTROL_CTS		2
130 #define DIGI_OUTPUT_FLOW_CONTROL_DSR		4
131 
132 #define DIGI_DTR_INACTIVE			0
133 #define DIGI_DTR_ACTIVE				1
134 #define DIGI_DTR_INPUT_FLOW_CONTROL		2
135 
136 #define DIGI_RTS_INACTIVE			0
137 #define DIGI_RTS_ACTIVE				1
138 #define DIGI_RTS_INPUT_FLOW_CONTROL		2
139 #define DIGI_RTS_TOGGLE				3
140 
141 #define DIGI_FLUSH_TX				1
142 #define DIGI_FLUSH_RX				2
143 #define DIGI_RESUME_TX				4 /* clears xoff condition */
144 
145 #define DIGI_TRANSMIT_NOT_IDLE			0
146 #define DIGI_TRANSMIT_IDLE			1
147 
148 #define DIGI_DISABLE				0
149 #define DIGI_ENABLE				1
150 
151 #define DIGI_DEASSERT				0
152 #define DIGI_ASSERT				1
153 
154 /* in band status codes */
155 #define DIGI_OVERRUN_ERROR			4
156 #define DIGI_PARITY_ERROR			8
157 #define DIGI_FRAMING_ERROR			16
158 #define DIGI_BREAK_ERROR			32
159 
160 /* out of band status */
161 #define DIGI_NO_ERROR				0
162 #define DIGI_BAD_FIRST_PARAMETER		1
163 #define DIGI_BAD_SECOND_PARAMETER		2
164 #define DIGI_INVALID_LINE			3
165 #define DIGI_INVALID_OPCODE			4
166 
167 /* input signals */
168 #define DIGI_READ_INPUT_SIGNALS_SLOT		1
169 #define DIGI_READ_INPUT_SIGNALS_ERR		2
170 #define DIGI_READ_INPUT_SIGNALS_BUSY		4
171 #define DIGI_READ_INPUT_SIGNALS_PE		8
172 #define DIGI_READ_INPUT_SIGNALS_CTS		16
173 #define DIGI_READ_INPUT_SIGNALS_DSR		32
174 #define DIGI_READ_INPUT_SIGNALS_RI		64
175 #define DIGI_READ_INPUT_SIGNALS_DCD		128
176 
177 
178 /* Structures */
179 
180 struct digi_serial {
181 	spinlock_t ds_serial_lock;
182 	struct usb_serial_port *ds_oob_port;	/* out-of-band port */
183 	int ds_oob_port_num;			/* index of out-of-band port */
184 	int ds_device_started;
185 };
186 
187 struct digi_port {
188 	spinlock_t dp_port_lock;
189 	int dp_port_num;
190 	int dp_out_buf_len;
191 	unsigned char dp_out_buf[DIGI_OUT_BUF_SIZE];
192 	int dp_write_urb_in_use;
193 	unsigned int dp_modem_signals;
194 	int dp_transmit_idle;
195 	wait_queue_head_t dp_transmit_idle_wait;
196 	int dp_throttled;
197 	int dp_throttle_restart;
198 	wait_queue_head_t dp_flush_wait;
199 	wait_queue_head_t dp_close_wait;	/* wait queue for close */
200 	wait_queue_head_t write_wait;
201 	struct usb_serial_port *dp_port;
202 };
203 
204 
205 /* Local Function Declarations */
206 
207 static int digi_write_oob_command(struct usb_serial_port *port,
208 	unsigned char *buf, int count, int interruptible);
209 static int digi_write_inb_command(struct usb_serial_port *port,
210 	unsigned char *buf, int count, unsigned long timeout);
211 static int digi_set_modem_signals(struct usb_serial_port *port,
212 	unsigned int modem_signals, int interruptible);
213 static int digi_transmit_idle(struct usb_serial_port *port,
214 	unsigned long timeout);
215 static void digi_rx_throttle(struct tty_struct *tty);
216 static void digi_rx_unthrottle(struct tty_struct *tty);
217 static void digi_set_termios(struct tty_struct *tty,
218 		struct usb_serial_port *port, struct ktermios *old_termios);
219 static void digi_break_ctl(struct tty_struct *tty, int break_state);
220 static int digi_tiocmget(struct tty_struct *tty);
221 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
222 		unsigned int clear);
223 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
224 		const unsigned char *buf, int count);
225 static void digi_write_bulk_callback(struct urb *urb);
226 static unsigned int digi_write_room(struct tty_struct *tty);
227 static unsigned int digi_chars_in_buffer(struct tty_struct *tty);
228 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
229 static void digi_close(struct usb_serial_port *port);
230 static void digi_dtr_rts(struct usb_serial_port *port, int on);
231 static int digi_startup_device(struct usb_serial *serial);
232 static int digi_startup(struct usb_serial *serial);
233 static void digi_disconnect(struct usb_serial *serial);
234 static void digi_release(struct usb_serial *serial);
235 static int digi_port_probe(struct usb_serial_port *port);
236 static void digi_port_remove(struct usb_serial_port *port);
237 static void digi_read_bulk_callback(struct urb *urb);
238 static int digi_read_inb_callback(struct urb *urb);
239 static int digi_read_oob_callback(struct urb *urb);
240 
241 
242 static const struct usb_device_id id_table_combined[] = {
243 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
244 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
245 	{ }						/* Terminating entry */
246 };
247 
248 static const struct usb_device_id id_table_2[] = {
249 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
250 	{ }						/* Terminating entry */
251 };
252 
253 static const struct usb_device_id id_table_4[] = {
254 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
255 	{ }						/* Terminating entry */
256 };
257 
258 MODULE_DEVICE_TABLE(usb, id_table_combined);
259 
260 /* device info needed for the Digi serial converter */
261 
262 static struct usb_serial_driver digi_acceleport_2_device = {
263 	.driver = {
264 		.owner =		THIS_MODULE,
265 		.name =			"digi_2",
266 	},
267 	.description =			"Digi 2 port USB adapter",
268 	.id_table =			id_table_2,
269 	.num_ports =			3,
270 	.num_bulk_in =			4,
271 	.num_bulk_out =			4,
272 	.open =				digi_open,
273 	.close =			digi_close,
274 	.dtr_rts =			digi_dtr_rts,
275 	.write =			digi_write,
276 	.write_room =			digi_write_room,
277 	.write_bulk_callback = 		digi_write_bulk_callback,
278 	.read_bulk_callback =		digi_read_bulk_callback,
279 	.chars_in_buffer =		digi_chars_in_buffer,
280 	.throttle =			digi_rx_throttle,
281 	.unthrottle =			digi_rx_unthrottle,
282 	.set_termios =			digi_set_termios,
283 	.break_ctl =			digi_break_ctl,
284 	.tiocmget =			digi_tiocmget,
285 	.tiocmset =			digi_tiocmset,
286 	.attach =			digi_startup,
287 	.disconnect =			digi_disconnect,
288 	.release =			digi_release,
289 	.port_probe =			digi_port_probe,
290 	.port_remove =			digi_port_remove,
291 };
292 
293 static struct usb_serial_driver digi_acceleport_4_device = {
294 	.driver = {
295 		.owner =		THIS_MODULE,
296 		.name =			"digi_4",
297 	},
298 	.description =			"Digi 4 port USB adapter",
299 	.id_table =			id_table_4,
300 	.num_ports =			4,
301 	.num_bulk_in =			5,
302 	.num_bulk_out =			5,
303 	.open =				digi_open,
304 	.close =			digi_close,
305 	.write =			digi_write,
306 	.write_room =			digi_write_room,
307 	.write_bulk_callback = 		digi_write_bulk_callback,
308 	.read_bulk_callback =		digi_read_bulk_callback,
309 	.chars_in_buffer =		digi_chars_in_buffer,
310 	.throttle =			digi_rx_throttle,
311 	.unthrottle =			digi_rx_unthrottle,
312 	.set_termios =			digi_set_termios,
313 	.break_ctl =			digi_break_ctl,
314 	.tiocmget =			digi_tiocmget,
315 	.tiocmset =			digi_tiocmset,
316 	.attach =			digi_startup,
317 	.disconnect =			digi_disconnect,
318 	.release =			digi_release,
319 	.port_probe =			digi_port_probe,
320 	.port_remove =			digi_port_remove,
321 };
322 
323 static struct usb_serial_driver * const serial_drivers[] = {
324 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
325 };
326 
327 /* Functions */
328 
329 /*
330  *  Cond Wait Interruptible Timeout Irqrestore
331  *
332  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
333  *  so that wake ups are not lost if they occur between the unlock
334  *  and the sleep.  In other words, spin_unlock_irqrestore and
335  *  interruptible_sleep_on_timeout are "atomic" with respect to
336  *  wake ups.  This is used to implement condition variables.
337  *
338  *  interruptible_sleep_on_timeout is deprecated and has been replaced
339  *  with the equivalent code.
340  */
341 
342 static long cond_wait_interruptible_timeout_irqrestore(
343 	wait_queue_head_t *q, long timeout,
344 	spinlock_t *lock, unsigned long flags)
345 __releases(lock)
346 {
347 	DEFINE_WAIT(wait);
348 
349 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
350 	spin_unlock_irqrestore(lock, flags);
351 	timeout = schedule_timeout(timeout);
352 	finish_wait(q, &wait);
353 
354 	return timeout;
355 }
356 
357 /*
358  *  Digi Write OOB Command
359  *
360  *  Write commands on the out of band port.  Commands are 4
361  *  bytes each, multiple commands can be sent at once, and
362  *  no command will be split across USB packets.  Returns 0
363  *  if successful, -EINTR if interrupted while sleeping and
364  *  the interruptible flag is true, or a negative error
365  *  returned by usb_submit_urb.
366  */
367 
368 static int digi_write_oob_command(struct usb_serial_port *port,
369 	unsigned char *buf, int count, int interruptible)
370 {
371 	int ret = 0;
372 	int len;
373 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
374 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
375 	unsigned long flags;
376 
377 	dev_dbg(&port->dev,
378 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
379 		oob_priv->dp_port_num, count);
380 
381 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
382 	while (count > 0) {
383 		while (oob_priv->dp_write_urb_in_use) {
384 			cond_wait_interruptible_timeout_irqrestore(
385 				&oob_priv->write_wait, DIGI_RETRY_TIMEOUT,
386 				&oob_priv->dp_port_lock, flags);
387 			if (interruptible && signal_pending(current))
388 				return -EINTR;
389 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
390 		}
391 
392 		/* len must be a multiple of 4, so commands are not split */
393 		len = min(count, oob_port->bulk_out_size);
394 		if (len > 4)
395 			len &= ~3;
396 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
397 		oob_port->write_urb->transfer_buffer_length = len;
398 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
399 		if (ret == 0) {
400 			oob_priv->dp_write_urb_in_use = 1;
401 			count -= len;
402 			buf += len;
403 		}
404 	}
405 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
406 	if (ret)
407 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
408 			__func__, ret);
409 	return ret;
410 
411 }
412 
413 
414 /*
415  *  Digi Write In Band Command
416  *
417  *  Write commands on the given port.  Commands are 4
418  *  bytes each, multiple commands can be sent at once, and
419  *  no command will be split across USB packets.  If timeout
420  *  is non-zero, write in band command will return after
421  *  waiting unsuccessfully for the URB status to clear for
422  *  timeout ticks.  Returns 0 if successful, or a negative
423  *  error returned by digi_write.
424  */
425 
426 static int digi_write_inb_command(struct usb_serial_port *port,
427 	unsigned char *buf, int count, unsigned long timeout)
428 {
429 	int ret = 0;
430 	int len;
431 	struct digi_port *priv = usb_get_serial_port_data(port);
432 	unsigned char *data = port->write_urb->transfer_buffer;
433 	unsigned long flags;
434 
435 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
436 		priv->dp_port_num, count);
437 
438 	if (timeout)
439 		timeout += jiffies;
440 	else
441 		timeout = ULONG_MAX;
442 
443 	spin_lock_irqsave(&priv->dp_port_lock, flags);
444 	while (count > 0 && ret == 0) {
445 		while (priv->dp_write_urb_in_use &&
446 		       time_before(jiffies, timeout)) {
447 			cond_wait_interruptible_timeout_irqrestore(
448 				&priv->write_wait, DIGI_RETRY_TIMEOUT,
449 				&priv->dp_port_lock, flags);
450 			if (signal_pending(current))
451 				return -EINTR;
452 			spin_lock_irqsave(&priv->dp_port_lock, flags);
453 		}
454 
455 		/* len must be a multiple of 4 and small enough to */
456 		/* guarantee the write will send buffered data first, */
457 		/* so commands are in order with data and not split */
458 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
459 		if (len > 4)
460 			len &= ~3;
461 
462 		/* write any buffered data first */
463 		if (priv->dp_out_buf_len > 0) {
464 			data[0] = DIGI_CMD_SEND_DATA;
465 			data[1] = priv->dp_out_buf_len;
466 			memcpy(data + 2, priv->dp_out_buf,
467 				priv->dp_out_buf_len);
468 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
469 			port->write_urb->transfer_buffer_length
470 				= priv->dp_out_buf_len + 2 + len;
471 		} else {
472 			memcpy(data, buf, len);
473 			port->write_urb->transfer_buffer_length = len;
474 		}
475 
476 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
477 		if (ret == 0) {
478 			priv->dp_write_urb_in_use = 1;
479 			priv->dp_out_buf_len = 0;
480 			count -= len;
481 			buf += len;
482 		}
483 
484 	}
485 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
486 
487 	if (ret)
488 		dev_err(&port->dev,
489 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
490 			__func__, ret, priv->dp_port_num);
491 	return ret;
492 }
493 
494 
495 /*
496  *  Digi Set Modem Signals
497  *
498  *  Sets or clears DTR and RTS on the port, according to the
499  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
500  *  for the modem_signals argument.  Returns 0 if successful,
501  *  -EINTR if interrupted while sleeping, or a non-zero error
502  *  returned by usb_submit_urb.
503  */
504 
505 static int digi_set_modem_signals(struct usb_serial_port *port,
506 	unsigned int modem_signals, int interruptible)
507 {
508 
509 	int ret;
510 	struct digi_port *port_priv = usb_get_serial_port_data(port);
511 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
512 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
513 	unsigned char *data = oob_port->write_urb->transfer_buffer;
514 	unsigned long flags;
515 
516 	dev_dbg(&port->dev,
517 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
518 		port_priv->dp_port_num, modem_signals);
519 
520 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
521 	spin_lock(&port_priv->dp_port_lock);
522 
523 	while (oob_priv->dp_write_urb_in_use) {
524 		spin_unlock(&port_priv->dp_port_lock);
525 		cond_wait_interruptible_timeout_irqrestore(
526 			&oob_priv->write_wait, DIGI_RETRY_TIMEOUT,
527 			&oob_priv->dp_port_lock, flags);
528 		if (interruptible && signal_pending(current))
529 			return -EINTR;
530 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
531 		spin_lock(&port_priv->dp_port_lock);
532 	}
533 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
534 	data[1] = port_priv->dp_port_num;
535 	data[2] = (modem_signals & TIOCM_DTR) ?
536 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
537 	data[3] = 0;
538 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
539 	data[5] = port_priv->dp_port_num;
540 	data[6] = (modem_signals & TIOCM_RTS) ?
541 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
542 	data[7] = 0;
543 
544 	oob_port->write_urb->transfer_buffer_length = 8;
545 
546 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
547 	if (ret == 0) {
548 		oob_priv->dp_write_urb_in_use = 1;
549 		port_priv->dp_modem_signals &= ~(TIOCM_DTR | TIOCM_RTS);
550 		port_priv->dp_modem_signals |=
551 				modem_signals & (TIOCM_DTR | TIOCM_RTS);
552 	}
553 	spin_unlock(&port_priv->dp_port_lock);
554 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
555 	if (ret)
556 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
557 			__func__, ret);
558 	return ret;
559 }
560 
561 /*
562  *  Digi Transmit Idle
563  *
564  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
565  *  to go idle.  It returns 0 if successful or a negative error.
566  *
567  *  There are race conditions here if more than one process is calling
568  *  digi_transmit_idle on the same port at the same time.  However, this
569  *  is only called from close, and only one process can be in close on a
570  *  port at a time, so its ok.
571  */
572 
573 static int digi_transmit_idle(struct usb_serial_port *port,
574 	unsigned long timeout)
575 {
576 	int ret;
577 	unsigned char buf[2];
578 	struct digi_port *priv = usb_get_serial_port_data(port);
579 	unsigned long flags;
580 
581 	spin_lock_irqsave(&priv->dp_port_lock, flags);
582 	priv->dp_transmit_idle = 0;
583 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
584 
585 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
586 	buf[1] = 0;
587 
588 	timeout += jiffies;
589 
590 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
591 	if (ret != 0)
592 		return ret;
593 
594 	spin_lock_irqsave(&priv->dp_port_lock, flags);
595 
596 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
597 		cond_wait_interruptible_timeout_irqrestore(
598 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
599 			&priv->dp_port_lock, flags);
600 		if (signal_pending(current))
601 			return -EINTR;
602 		spin_lock_irqsave(&priv->dp_port_lock, flags);
603 	}
604 	priv->dp_transmit_idle = 0;
605 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
606 	return 0;
607 
608 }
609 
610 
611 static void digi_rx_throttle(struct tty_struct *tty)
612 {
613 	unsigned long flags;
614 	struct usb_serial_port *port = tty->driver_data;
615 	struct digi_port *priv = usb_get_serial_port_data(port);
616 
617 	/* stop receiving characters by not resubmitting the read urb */
618 	spin_lock_irqsave(&priv->dp_port_lock, flags);
619 	priv->dp_throttled = 1;
620 	priv->dp_throttle_restart = 0;
621 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
622 }
623 
624 
625 static void digi_rx_unthrottle(struct tty_struct *tty)
626 {
627 	int ret = 0;
628 	unsigned long flags;
629 	struct usb_serial_port *port = tty->driver_data;
630 	struct digi_port *priv = usb_get_serial_port_data(port);
631 
632 	spin_lock_irqsave(&priv->dp_port_lock, flags);
633 
634 	/* restart read chain */
635 	if (priv->dp_throttle_restart)
636 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
637 
638 	/* turn throttle off */
639 	priv->dp_throttled = 0;
640 	priv->dp_throttle_restart = 0;
641 
642 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
643 
644 	if (ret)
645 		dev_err(&port->dev,
646 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
647 			__func__, ret, priv->dp_port_num);
648 }
649 
650 
651 static void digi_set_termios(struct tty_struct *tty,
652 		struct usb_serial_port *port, struct ktermios *old_termios)
653 {
654 	struct digi_port *priv = usb_get_serial_port_data(port);
655 	struct device *dev = &port->dev;
656 	unsigned int iflag = tty->termios.c_iflag;
657 	unsigned int cflag = tty->termios.c_cflag;
658 	unsigned int old_iflag = old_termios->c_iflag;
659 	unsigned int old_cflag = old_termios->c_cflag;
660 	unsigned char buf[32];
661 	unsigned int modem_signals;
662 	int arg, ret;
663 	int i = 0;
664 	speed_t baud;
665 
666 	dev_dbg(dev,
667 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
668 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
669 
670 	/* set baud rate */
671 	baud = tty_get_baud_rate(tty);
672 	if (baud != tty_termios_baud_rate(old_termios)) {
673 		arg = -1;
674 
675 		/* reassert DTR and (maybe) RTS on transition from B0 */
676 		if ((old_cflag & CBAUD) == B0) {
677 			/* don't set RTS if using hardware flow control */
678 			/* and throttling input */
679 			modem_signals = TIOCM_DTR;
680 			if (!C_CRTSCTS(tty) || !tty_throttled(tty))
681 				modem_signals |= TIOCM_RTS;
682 			digi_set_modem_signals(port, modem_signals, 1);
683 		}
684 		switch (baud) {
685 		/* drop DTR and RTS on transition to B0 */
686 		case 0: digi_set_modem_signals(port, 0, 1); break;
687 		case 50: arg = DIGI_BAUD_50; break;
688 		case 75: arg = DIGI_BAUD_75; break;
689 		case 110: arg = DIGI_BAUD_110; break;
690 		case 150: arg = DIGI_BAUD_150; break;
691 		case 200: arg = DIGI_BAUD_200; break;
692 		case 300: arg = DIGI_BAUD_300; break;
693 		case 600: arg = DIGI_BAUD_600; break;
694 		case 1200: arg = DIGI_BAUD_1200; break;
695 		case 1800: arg = DIGI_BAUD_1800; break;
696 		case 2400: arg = DIGI_BAUD_2400; break;
697 		case 4800: arg = DIGI_BAUD_4800; break;
698 		case 9600: arg = DIGI_BAUD_9600; break;
699 		case 19200: arg = DIGI_BAUD_19200; break;
700 		case 38400: arg = DIGI_BAUD_38400; break;
701 		case 57600: arg = DIGI_BAUD_57600; break;
702 		case 115200: arg = DIGI_BAUD_115200; break;
703 		case 230400: arg = DIGI_BAUD_230400; break;
704 		case 460800: arg = DIGI_BAUD_460800; break;
705 		default:
706 			arg = DIGI_BAUD_9600;
707 			baud = 9600;
708 			break;
709 		}
710 		if (arg != -1) {
711 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
712 			buf[i++] = priv->dp_port_num;
713 			buf[i++] = arg;
714 			buf[i++] = 0;
715 		}
716 	}
717 	/* set parity */
718 	tty->termios.c_cflag &= ~CMSPAR;
719 
720 	if ((cflag & (PARENB | PARODD)) != (old_cflag & (PARENB | PARODD))) {
721 		if (cflag & PARENB) {
722 			if (cflag & PARODD)
723 				arg = DIGI_PARITY_ODD;
724 			else
725 				arg = DIGI_PARITY_EVEN;
726 		} else {
727 			arg = DIGI_PARITY_NONE;
728 		}
729 		buf[i++] = DIGI_CMD_SET_PARITY;
730 		buf[i++] = priv->dp_port_num;
731 		buf[i++] = arg;
732 		buf[i++] = 0;
733 	}
734 	/* set word size */
735 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
736 		arg = -1;
737 		switch (cflag & CSIZE) {
738 		case CS5: arg = DIGI_WORD_SIZE_5; break;
739 		case CS6: arg = DIGI_WORD_SIZE_6; break;
740 		case CS7: arg = DIGI_WORD_SIZE_7; break;
741 		case CS8: arg = DIGI_WORD_SIZE_8; break;
742 		default:
743 			dev_dbg(dev,
744 				"digi_set_termios: can't handle word size %d\n",
745 				cflag & CSIZE);
746 			break;
747 		}
748 
749 		if (arg != -1) {
750 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
751 			buf[i++] = priv->dp_port_num;
752 			buf[i++] = arg;
753 			buf[i++] = 0;
754 		}
755 
756 	}
757 
758 	/* set stop bits */
759 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
760 
761 		if ((cflag & CSTOPB))
762 			arg = DIGI_STOP_BITS_2;
763 		else
764 			arg = DIGI_STOP_BITS_1;
765 
766 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
767 		buf[i++] = priv->dp_port_num;
768 		buf[i++] = arg;
769 		buf[i++] = 0;
770 
771 	}
772 
773 	/* set input flow control */
774 	if ((iflag & IXOFF) != (old_iflag & IXOFF) ||
775 			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
776 		arg = 0;
777 		if (iflag & IXOFF)
778 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
779 		else
780 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
781 
782 		if (cflag & CRTSCTS) {
783 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
784 
785 			/* On USB-4 it is necessary to assert RTS prior */
786 			/* to selecting RTS input flow control.  */
787 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
788 			buf[i++] = priv->dp_port_num;
789 			buf[i++] = DIGI_RTS_ACTIVE;
790 			buf[i++] = 0;
791 
792 		} else {
793 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
794 		}
795 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
796 		buf[i++] = priv->dp_port_num;
797 		buf[i++] = arg;
798 		buf[i++] = 0;
799 	}
800 
801 	/* set output flow control */
802 	if ((iflag & IXON) != (old_iflag & IXON) ||
803 			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
804 		arg = 0;
805 		if (iflag & IXON)
806 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
807 		else
808 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
809 
810 		if (cflag & CRTSCTS)
811 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
812 		else
813 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
814 
815 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
816 		buf[i++] = priv->dp_port_num;
817 		buf[i++] = arg;
818 		buf[i++] = 0;
819 	}
820 
821 	/* set receive enable/disable */
822 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
823 		if (cflag & CREAD)
824 			arg = DIGI_ENABLE;
825 		else
826 			arg = DIGI_DISABLE;
827 
828 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
829 		buf[i++] = priv->dp_port_num;
830 		buf[i++] = arg;
831 		buf[i++] = 0;
832 	}
833 	ret = digi_write_oob_command(port, buf, i, 1);
834 	if (ret != 0)
835 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
836 	tty_encode_baud_rate(tty, baud, baud);
837 }
838 
839 
840 static void digi_break_ctl(struct tty_struct *tty, int break_state)
841 {
842 	struct usb_serial_port *port = tty->driver_data;
843 	unsigned char buf[4];
844 
845 	buf[0] = DIGI_CMD_BREAK_CONTROL;
846 	buf[1] = 2;				/* length */
847 	buf[2] = break_state ? 1 : 0;
848 	buf[3] = 0;				/* pad */
849 	digi_write_inb_command(port, buf, 4, 0);
850 }
851 
852 
853 static int digi_tiocmget(struct tty_struct *tty)
854 {
855 	struct usb_serial_port *port = tty->driver_data;
856 	struct digi_port *priv = usb_get_serial_port_data(port);
857 	unsigned int val;
858 	unsigned long flags;
859 
860 	spin_lock_irqsave(&priv->dp_port_lock, flags);
861 	val = priv->dp_modem_signals;
862 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
863 	return val;
864 }
865 
866 
867 static int digi_tiocmset(struct tty_struct *tty,
868 					unsigned int set, unsigned int clear)
869 {
870 	struct usb_serial_port *port = tty->driver_data;
871 	struct digi_port *priv = usb_get_serial_port_data(port);
872 	unsigned int val;
873 	unsigned long flags;
874 
875 	spin_lock_irqsave(&priv->dp_port_lock, flags);
876 	val = (priv->dp_modem_signals & ~clear) | set;
877 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
878 	return digi_set_modem_signals(port, val, 1);
879 }
880 
881 
882 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
883 					const unsigned char *buf, int count)
884 {
885 
886 	int ret, data_len, new_len;
887 	struct digi_port *priv = usb_get_serial_port_data(port);
888 	unsigned char *data = port->write_urb->transfer_buffer;
889 	unsigned long flags;
890 
891 	dev_dbg(&port->dev, "digi_write: TOP: port=%d, count=%d\n",
892 		priv->dp_port_num, count);
893 
894 	/* copy user data (which can sleep) before getting spin lock */
895 	count = min(count, port->bulk_out_size-2);
896 	count = min(64, count);
897 
898 	/* be sure only one write proceeds at a time */
899 	/* there are races on the port private buffer */
900 	spin_lock_irqsave(&priv->dp_port_lock, flags);
901 
902 	/* wait for urb status clear to submit another urb */
903 	if (priv->dp_write_urb_in_use) {
904 		/* buffer data if count is 1 (probably put_char) if possible */
905 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
906 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
907 			new_len = 1;
908 		} else {
909 			new_len = 0;
910 		}
911 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
912 		return new_len;
913 	}
914 
915 	/* allow space for any buffered data and for new data, up to */
916 	/* transfer buffer size - 2 (for command and length bytes) */
917 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
918 	data_len = new_len + priv->dp_out_buf_len;
919 
920 	if (data_len == 0) {
921 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
922 		return 0;
923 	}
924 
925 	port->write_urb->transfer_buffer_length = data_len+2;
926 
927 	*data++ = DIGI_CMD_SEND_DATA;
928 	*data++ = data_len;
929 
930 	/* copy in buffered data first */
931 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
932 	data += priv->dp_out_buf_len;
933 
934 	/* copy in new data */
935 	memcpy(data, buf, new_len);
936 
937 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
938 	if (ret == 0) {
939 		priv->dp_write_urb_in_use = 1;
940 		ret = new_len;
941 		priv->dp_out_buf_len = 0;
942 	}
943 
944 	/* return length of new data written, or error */
945 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
946 	if (ret < 0)
947 		dev_err_console(port,
948 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
949 			__func__, ret, priv->dp_port_num);
950 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
951 	return ret;
952 
953 }
954 
955 static void digi_write_bulk_callback(struct urb *urb)
956 {
957 
958 	struct usb_serial_port *port = urb->context;
959 	struct usb_serial *serial;
960 	struct digi_port *priv;
961 	struct digi_serial *serial_priv;
962 	unsigned long flags;
963 	int ret = 0;
964 	int status = urb->status;
965 	bool wakeup;
966 
967 	/* port and serial sanity check */
968 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
969 		pr_err("%s: port or port->private is NULL, status=%d\n",
970 			__func__, status);
971 		return;
972 	}
973 	serial = port->serial;
974 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
975 		dev_err(&port->dev,
976 			"%s: serial or serial->private is NULL, status=%d\n",
977 			__func__, status);
978 		return;
979 	}
980 
981 	/* handle oob callback */
982 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
983 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
984 		spin_lock_irqsave(&priv->dp_port_lock, flags);
985 		priv->dp_write_urb_in_use = 0;
986 		wake_up_interruptible(&priv->write_wait);
987 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
988 		return;
989 	}
990 
991 	/* try to send any buffered data on this port */
992 	wakeup = true;
993 	spin_lock_irqsave(&priv->dp_port_lock, flags);
994 	priv->dp_write_urb_in_use = 0;
995 	if (priv->dp_out_buf_len > 0) {
996 		*((unsigned char *)(port->write_urb->transfer_buffer))
997 			= (unsigned char)DIGI_CMD_SEND_DATA;
998 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
999 			= (unsigned char)priv->dp_out_buf_len;
1000 		port->write_urb->transfer_buffer_length =
1001 						priv->dp_out_buf_len + 2;
1002 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1003 			priv->dp_out_buf_len);
1004 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1005 		if (ret == 0) {
1006 			priv->dp_write_urb_in_use = 1;
1007 			priv->dp_out_buf_len = 0;
1008 			wakeup = false;
1009 		}
1010 	}
1011 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1012 
1013 	if (ret && ret != -EPERM)
1014 		dev_err_console(port,
1015 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1016 			__func__, ret, priv->dp_port_num);
1017 
1018 	if (wakeup)
1019 		tty_port_tty_wakeup(&port->port);
1020 }
1021 
1022 static unsigned int digi_write_room(struct tty_struct *tty)
1023 {
1024 	struct usb_serial_port *port = tty->driver_data;
1025 	struct digi_port *priv = usb_get_serial_port_data(port);
1026 	unsigned long flags;
1027 	unsigned int room;
1028 
1029 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1030 
1031 	if (priv->dp_write_urb_in_use)
1032 		room = 0;
1033 	else
1034 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1035 
1036 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1037 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%u\n", priv->dp_port_num, room);
1038 	return room;
1039 
1040 }
1041 
1042 static unsigned int digi_chars_in_buffer(struct tty_struct *tty)
1043 {
1044 	struct usb_serial_port *port = tty->driver_data;
1045 	struct digi_port *priv = usb_get_serial_port_data(port);
1046 	unsigned long flags;
1047 	unsigned int chars;
1048 
1049 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1050 	if (priv->dp_write_urb_in_use)
1051 		chars = port->bulk_out_size - 2;
1052 	else
1053 		chars = priv->dp_out_buf_len;
1054 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1055 
1056 	dev_dbg(&port->dev, "%s: port=%d, chars=%d\n", __func__,
1057 			priv->dp_port_num, chars);
1058 	return chars;
1059 }
1060 
1061 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1062 {
1063 	/* Adjust DTR and RTS */
1064 	digi_set_modem_signals(port, on * (TIOCM_DTR | TIOCM_RTS), 1);
1065 }
1066 
1067 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1068 {
1069 	int ret;
1070 	unsigned char buf[32];
1071 	struct digi_port *priv = usb_get_serial_port_data(port);
1072 	struct ktermios not_termios;
1073 
1074 	/* be sure the device is started up */
1075 	if (digi_startup_device(port->serial) != 0)
1076 		return -ENXIO;
1077 
1078 	/* read modem signals automatically whenever they change */
1079 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1080 	buf[1] = priv->dp_port_num;
1081 	buf[2] = DIGI_ENABLE;
1082 	buf[3] = 0;
1083 
1084 	/* flush fifos */
1085 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1086 	buf[5] = priv->dp_port_num;
1087 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1088 	buf[7] = 0;
1089 
1090 	ret = digi_write_oob_command(port, buf, 8, 1);
1091 	if (ret != 0)
1092 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1093 
1094 	/* set termios settings */
1095 	if (tty) {
1096 		not_termios.c_cflag = ~tty->termios.c_cflag;
1097 		not_termios.c_iflag = ~tty->termios.c_iflag;
1098 		digi_set_termios(tty, port, &not_termios);
1099 	}
1100 	return 0;
1101 }
1102 
1103 
1104 static void digi_close(struct usb_serial_port *port)
1105 {
1106 	DEFINE_WAIT(wait);
1107 	int ret;
1108 	unsigned char buf[32];
1109 	struct digi_port *priv = usb_get_serial_port_data(port);
1110 
1111 	mutex_lock(&port->serial->disc_mutex);
1112 	/* if disconnected, just clear flags */
1113 	if (port->serial->disconnected)
1114 		goto exit;
1115 
1116 	/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1117 	digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1118 
1119 	/* disable input flow control */
1120 	buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1121 	buf[1] = priv->dp_port_num;
1122 	buf[2] = DIGI_DISABLE;
1123 	buf[3] = 0;
1124 
1125 	/* disable output flow control */
1126 	buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1127 	buf[5] = priv->dp_port_num;
1128 	buf[6] = DIGI_DISABLE;
1129 	buf[7] = 0;
1130 
1131 	/* disable reading modem signals automatically */
1132 	buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1133 	buf[9] = priv->dp_port_num;
1134 	buf[10] = DIGI_DISABLE;
1135 	buf[11] = 0;
1136 
1137 	/* disable receive */
1138 	buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1139 	buf[13] = priv->dp_port_num;
1140 	buf[14] = DIGI_DISABLE;
1141 	buf[15] = 0;
1142 
1143 	/* flush fifos */
1144 	buf[16] = DIGI_CMD_IFLUSH_FIFO;
1145 	buf[17] = priv->dp_port_num;
1146 	buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1147 	buf[19] = 0;
1148 
1149 	ret = digi_write_oob_command(port, buf, 20, 0);
1150 	if (ret != 0)
1151 		dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n",
1152 									ret);
1153 	/* wait for final commands on oob port to complete */
1154 	prepare_to_wait(&priv->dp_flush_wait, &wait,
1155 			TASK_INTERRUPTIBLE);
1156 	schedule_timeout(DIGI_CLOSE_TIMEOUT);
1157 	finish_wait(&priv->dp_flush_wait, &wait);
1158 
1159 	/* shutdown any outstanding bulk writes */
1160 	usb_kill_urb(port->write_urb);
1161 exit:
1162 	spin_lock_irq(&priv->dp_port_lock);
1163 	priv->dp_write_urb_in_use = 0;
1164 	wake_up_interruptible(&priv->dp_close_wait);
1165 	spin_unlock_irq(&priv->dp_port_lock);
1166 	mutex_unlock(&port->serial->disc_mutex);
1167 }
1168 
1169 
1170 /*
1171  *  Digi Startup Device
1172  *
1173  *  Starts reads on all ports.  Must be called AFTER startup, with
1174  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1175  */
1176 
1177 static int digi_startup_device(struct usb_serial *serial)
1178 {
1179 	int i, ret = 0;
1180 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1181 	struct usb_serial_port *port;
1182 
1183 	/* be sure this happens exactly once */
1184 	spin_lock(&serial_priv->ds_serial_lock);
1185 	if (serial_priv->ds_device_started) {
1186 		spin_unlock(&serial_priv->ds_serial_lock);
1187 		return 0;
1188 	}
1189 	serial_priv->ds_device_started = 1;
1190 	spin_unlock(&serial_priv->ds_serial_lock);
1191 
1192 	/* start reading from each bulk in endpoint for the device */
1193 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1194 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1195 		port = serial->port[i];
1196 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1197 		if (ret != 0) {
1198 			dev_err(&port->dev,
1199 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1200 				__func__, ret, i);
1201 			break;
1202 		}
1203 	}
1204 	return ret;
1205 }
1206 
1207 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1208 {
1209 	struct digi_port *priv;
1210 
1211 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1212 	if (!priv)
1213 		return -ENOMEM;
1214 
1215 	spin_lock_init(&priv->dp_port_lock);
1216 	priv->dp_port_num = port_num;
1217 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1218 	init_waitqueue_head(&priv->dp_flush_wait);
1219 	init_waitqueue_head(&priv->dp_close_wait);
1220 	init_waitqueue_head(&priv->write_wait);
1221 	priv->dp_port = port;
1222 
1223 	usb_set_serial_port_data(port, priv);
1224 
1225 	return 0;
1226 }
1227 
1228 static int digi_startup(struct usb_serial *serial)
1229 {
1230 	struct digi_serial *serial_priv;
1231 	int ret;
1232 
1233 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1234 	if (!serial_priv)
1235 		return -ENOMEM;
1236 
1237 	spin_lock_init(&serial_priv->ds_serial_lock);
1238 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1239 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1240 
1241 	ret = digi_port_init(serial_priv->ds_oob_port,
1242 						serial_priv->ds_oob_port_num);
1243 	if (ret) {
1244 		kfree(serial_priv);
1245 		return ret;
1246 	}
1247 
1248 	usb_set_serial_data(serial, serial_priv);
1249 
1250 	return 0;
1251 }
1252 
1253 
1254 static void digi_disconnect(struct usb_serial *serial)
1255 {
1256 	int i;
1257 
1258 	/* stop reads and writes on all ports */
1259 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1260 		usb_kill_urb(serial->port[i]->read_urb);
1261 		usb_kill_urb(serial->port[i]->write_urb);
1262 	}
1263 }
1264 
1265 
1266 static void digi_release(struct usb_serial *serial)
1267 {
1268 	struct digi_serial *serial_priv;
1269 	struct digi_port *priv;
1270 
1271 	serial_priv = usb_get_serial_data(serial);
1272 
1273 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1274 	kfree(priv);
1275 
1276 	kfree(serial_priv);
1277 }
1278 
1279 static int digi_port_probe(struct usb_serial_port *port)
1280 {
1281 	return digi_port_init(port, port->port_number);
1282 }
1283 
1284 static void digi_port_remove(struct usb_serial_port *port)
1285 {
1286 	struct digi_port *priv;
1287 
1288 	priv = usb_get_serial_port_data(port);
1289 	kfree(priv);
1290 }
1291 
1292 static void digi_read_bulk_callback(struct urb *urb)
1293 {
1294 	struct usb_serial_port *port = urb->context;
1295 	struct digi_port *priv;
1296 	struct digi_serial *serial_priv;
1297 	int ret;
1298 	int status = urb->status;
1299 
1300 	/* port sanity check, do not resubmit if port is not valid */
1301 	if (port == NULL)
1302 		return;
1303 	priv = usb_get_serial_port_data(port);
1304 	if (priv == NULL) {
1305 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1306 			__func__, status);
1307 		return;
1308 	}
1309 	if (port->serial == NULL ||
1310 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1311 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1312 			"is NULL, status=%d\n", __func__, status);
1313 		return;
1314 	}
1315 
1316 	/* do not resubmit urb if it has any status error */
1317 	if (status) {
1318 		dev_err(&port->dev,
1319 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1320 			__func__, status, priv->dp_port_num);
1321 		return;
1322 	}
1323 
1324 	/* handle oob or inb callback, do not resubmit if error */
1325 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1326 		if (digi_read_oob_callback(urb) != 0)
1327 			return;
1328 	} else {
1329 		if (digi_read_inb_callback(urb) != 0)
1330 			return;
1331 	}
1332 
1333 	/* continue read */
1334 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1335 	if (ret != 0 && ret != -EPERM) {
1336 		dev_err(&port->dev,
1337 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1338 			__func__, ret, priv->dp_port_num);
1339 	}
1340 
1341 }
1342 
1343 /*
1344  *  Digi Read INB Callback
1345  *
1346  *  Digi Read INB Callback handles reads on the in band ports, sending
1347  *  the data on to the tty subsystem.  When called we know port and
1348  *  port->private are not NULL and port->serial has been validated.
1349  *  It returns 0 if successful, 1 if successful but the port is
1350  *  throttled, and -1 if the sanity checks failed.
1351  */
1352 
1353 static int digi_read_inb_callback(struct urb *urb)
1354 {
1355 	struct usb_serial_port *port = urb->context;
1356 	struct digi_port *priv = usb_get_serial_port_data(port);
1357 	unsigned char *buf = urb->transfer_buffer;
1358 	unsigned long flags;
1359 	int opcode;
1360 	int len;
1361 	int port_status;
1362 	unsigned char *data;
1363 	int tty_flag, throttled;
1364 
1365 	/* short/multiple packet check */
1366 	if (urb->actual_length < 2) {
1367 		dev_warn(&port->dev, "short packet received\n");
1368 		return -1;
1369 	}
1370 
1371 	opcode = buf[0];
1372 	len = buf[1];
1373 
1374 	if (urb->actual_length != len + 2) {
1375 		dev_err(&port->dev, "malformed packet received: port=%d, opcode=%d, len=%d, actual_length=%u\n",
1376 			priv->dp_port_num, opcode, len, urb->actual_length);
1377 		return -1;
1378 	}
1379 
1380 	if (opcode == DIGI_CMD_RECEIVE_DATA && len < 1) {
1381 		dev_err(&port->dev, "malformed data packet received\n");
1382 		return -1;
1383 	}
1384 
1385 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1386 
1387 	/* check for throttle; if set, do not resubmit read urb */
1388 	/* indicate the read chain needs to be restarted on unthrottle */
1389 	throttled = priv->dp_throttled;
1390 	if (throttled)
1391 		priv->dp_throttle_restart = 1;
1392 
1393 	/* receive data */
1394 	if (opcode == DIGI_CMD_RECEIVE_DATA) {
1395 		port_status = buf[2];
1396 		data = &buf[3];
1397 
1398 		/* get flag from port_status */
1399 		tty_flag = 0;
1400 
1401 		/* overrun is special, not associated with a char */
1402 		if (port_status & DIGI_OVERRUN_ERROR)
1403 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1404 
1405 		/* break takes precedence over parity, */
1406 		/* which takes precedence over framing errors */
1407 		if (port_status & DIGI_BREAK_ERROR)
1408 			tty_flag = TTY_BREAK;
1409 		else if (port_status & DIGI_PARITY_ERROR)
1410 			tty_flag = TTY_PARITY;
1411 		else if (port_status & DIGI_FRAMING_ERROR)
1412 			tty_flag = TTY_FRAME;
1413 
1414 		/* data length is len-1 (one byte of len is port_status) */
1415 		--len;
1416 		if (len > 0) {
1417 			tty_insert_flip_string_fixed_flag(&port->port, data,
1418 					tty_flag, len);
1419 			tty_flip_buffer_push(&port->port);
1420 		}
1421 	}
1422 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1423 
1424 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1425 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1426 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1427 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1428 
1429 	return throttled ? 1 : 0;
1430 
1431 }
1432 
1433 
1434 /*
1435  *  Digi Read OOB Callback
1436  *
1437  *  Digi Read OOB Callback handles reads on the out of band port.
1438  *  When called we know port and port->private are not NULL and
1439  *  the port->serial is valid.  It returns 0 if successful, and
1440  *  -1 if the sanity checks failed.
1441  */
1442 
1443 static int digi_read_oob_callback(struct urb *urb)
1444 {
1445 
1446 	struct usb_serial_port *port = urb->context;
1447 	struct usb_serial *serial = port->serial;
1448 	struct tty_struct *tty;
1449 	struct digi_port *priv;
1450 	unsigned char *buf = urb->transfer_buffer;
1451 	int opcode, line, status, val;
1452 	unsigned long flags;
1453 	int i;
1454 	unsigned int rts;
1455 
1456 	if (urb->actual_length < 4)
1457 		return -1;
1458 
1459 	/* handle each oob command */
1460 	for (i = 0; i < urb->actual_length - 3; i += 4) {
1461 		opcode = buf[i];
1462 		line = buf[i + 1];
1463 		status = buf[i + 2];
1464 		val = buf[i + 3];
1465 
1466 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1467 			opcode, line, status, val);
1468 
1469 		if (status != 0 || line >= serial->type->num_ports)
1470 			continue;
1471 
1472 		port = serial->port[line];
1473 
1474 		priv = usb_get_serial_port_data(port);
1475 		if (priv == NULL)
1476 			return -1;
1477 
1478 		tty = tty_port_tty_get(&port->port);
1479 
1480 		rts = 0;
1481 		if (tty)
1482 			rts = C_CRTSCTS(tty);
1483 
1484 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1485 			bool wakeup = false;
1486 
1487 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1488 			/* convert from digi flags to termiox flags */
1489 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1490 				priv->dp_modem_signals |= TIOCM_CTS;
1491 				if (rts)
1492 					wakeup = true;
1493 			} else {
1494 				priv->dp_modem_signals &= ~TIOCM_CTS;
1495 				/* port must be open to use tty struct */
1496 			}
1497 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1498 				priv->dp_modem_signals |= TIOCM_DSR;
1499 			else
1500 				priv->dp_modem_signals &= ~TIOCM_DSR;
1501 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1502 				priv->dp_modem_signals |= TIOCM_RI;
1503 			else
1504 				priv->dp_modem_signals &= ~TIOCM_RI;
1505 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1506 				priv->dp_modem_signals |= TIOCM_CD;
1507 			else
1508 				priv->dp_modem_signals &= ~TIOCM_CD;
1509 
1510 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1511 
1512 			if (wakeup)
1513 				tty_port_tty_wakeup(&port->port);
1514 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1515 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1516 			priv->dp_transmit_idle = 1;
1517 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1518 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1519 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1520 			wake_up_interruptible(&priv->dp_flush_wait);
1521 		}
1522 		tty_kref_put(tty);
1523 	}
1524 	return 0;
1525 
1526 }
1527 
1528 module_usb_serial_driver(serial_drivers, id_table_combined);
1529 
1530 MODULE_AUTHOR(DRIVER_AUTHOR);
1531 MODULE_DESCRIPTION(DRIVER_DESC);
1532 MODULE_LICENSE("GPL");
1533