xref: /linux/drivers/usb/serial/digi_acceleport.c (revision 1e0731c05c985deb68a97fa44c1adcd3305dda90)
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,
219 			     const struct ktermios *old_termios);
220 static int digi_break_ctl(struct tty_struct *tty, int break_state);
221 static int digi_tiocmget(struct tty_struct *tty);
222 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
223 		unsigned int clear);
224 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
225 		const unsigned char *buf, int count);
226 static void digi_write_bulk_callback(struct urb *urb);
227 static unsigned int digi_write_room(struct tty_struct *tty);
228 static unsigned int digi_chars_in_buffer(struct tty_struct *tty);
229 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
230 static void digi_close(struct usb_serial_port *port);
231 static void digi_dtr_rts(struct usb_serial_port *port, int on);
232 static int digi_startup_device(struct usb_serial *serial);
233 static int digi_startup(struct usb_serial *serial);
234 static void digi_disconnect(struct usb_serial *serial);
235 static void digi_release(struct usb_serial *serial);
236 static int digi_port_probe(struct usb_serial_port *port);
237 static void digi_port_remove(struct usb_serial_port *port);
238 static void digi_read_bulk_callback(struct urb *urb);
239 static int digi_read_inb_callback(struct urb *urb);
240 static int digi_read_oob_callback(struct urb *urb);
241 
242 
243 static const struct usb_device_id id_table_combined[] = {
244 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
245 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
246 	{ }						/* Terminating entry */
247 };
248 
249 static const struct usb_device_id id_table_2[] = {
250 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
251 	{ }						/* Terminating entry */
252 };
253 
254 static const struct usb_device_id id_table_4[] = {
255 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
256 	{ }						/* Terminating entry */
257 };
258 
259 MODULE_DEVICE_TABLE(usb, id_table_combined);
260 
261 /* device info needed for the Digi serial converter */
262 
263 static struct usb_serial_driver digi_acceleport_2_device = {
264 	.driver = {
265 		.owner =		THIS_MODULE,
266 		.name =			"digi_2",
267 	},
268 	.description =			"Digi 2 port USB adapter",
269 	.id_table =			id_table_2,
270 	.num_ports =			3,
271 	.num_bulk_in =			4,
272 	.num_bulk_out =			4,
273 	.open =				digi_open,
274 	.close =			digi_close,
275 	.dtr_rts =			digi_dtr_rts,
276 	.write =			digi_write,
277 	.write_room =			digi_write_room,
278 	.write_bulk_callback = 		digi_write_bulk_callback,
279 	.read_bulk_callback =		digi_read_bulk_callback,
280 	.chars_in_buffer =		digi_chars_in_buffer,
281 	.throttle =			digi_rx_throttle,
282 	.unthrottle =			digi_rx_unthrottle,
283 	.set_termios =			digi_set_termios,
284 	.break_ctl =			digi_break_ctl,
285 	.tiocmget =			digi_tiocmget,
286 	.tiocmset =			digi_tiocmset,
287 	.attach =			digi_startup,
288 	.disconnect =			digi_disconnect,
289 	.release =			digi_release,
290 	.port_probe =			digi_port_probe,
291 	.port_remove =			digi_port_remove,
292 };
293 
294 static struct usb_serial_driver digi_acceleport_4_device = {
295 	.driver = {
296 		.owner =		THIS_MODULE,
297 		.name =			"digi_4",
298 	},
299 	.description =			"Digi 4 port USB adapter",
300 	.id_table =			id_table_4,
301 	.num_ports =			4,
302 	.num_bulk_in =			5,
303 	.num_bulk_out =			5,
304 	.open =				digi_open,
305 	.close =			digi_close,
306 	.write =			digi_write,
307 	.write_room =			digi_write_room,
308 	.write_bulk_callback = 		digi_write_bulk_callback,
309 	.read_bulk_callback =		digi_read_bulk_callback,
310 	.chars_in_buffer =		digi_chars_in_buffer,
311 	.throttle =			digi_rx_throttle,
312 	.unthrottle =			digi_rx_unthrottle,
313 	.set_termios =			digi_set_termios,
314 	.break_ctl =			digi_break_ctl,
315 	.tiocmget =			digi_tiocmget,
316 	.tiocmset =			digi_tiocmset,
317 	.attach =			digi_startup,
318 	.disconnect =			digi_disconnect,
319 	.release =			digi_release,
320 	.port_probe =			digi_port_probe,
321 	.port_remove =			digi_port_remove,
322 };
323 
324 static struct usb_serial_driver * const serial_drivers[] = {
325 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
326 };
327 
328 /* Functions */
329 
330 /*
331  *  Cond Wait Interruptible Timeout Irqrestore
332  *
333  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
334  *  so that wake ups are not lost if they occur between the unlock
335  *  and the sleep.  In other words, spin_unlock_irqrestore and
336  *  interruptible_sleep_on_timeout are "atomic" with respect to
337  *  wake ups.  This is used to implement condition variables.
338  *
339  *  interruptible_sleep_on_timeout is deprecated and has been replaced
340  *  with the equivalent code.
341  */
342 
343 static long cond_wait_interruptible_timeout_irqrestore(
344 	wait_queue_head_t *q, long timeout,
345 	spinlock_t *lock, unsigned long flags)
346 __releases(lock)
347 {
348 	DEFINE_WAIT(wait);
349 
350 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
351 	spin_unlock_irqrestore(lock, flags);
352 	timeout = schedule_timeout(timeout);
353 	finish_wait(q, &wait);
354 
355 	return timeout;
356 }
357 
358 /*
359  *  Digi Write OOB Command
360  *
361  *  Write commands on the out of band port.  Commands are 4
362  *  bytes each, multiple commands can be sent at once, and
363  *  no command will be split across USB packets.  Returns 0
364  *  if successful, -EINTR if interrupted while sleeping and
365  *  the interruptible flag is true, or a negative error
366  *  returned by usb_submit_urb.
367  */
368 
369 static int digi_write_oob_command(struct usb_serial_port *port,
370 	unsigned char *buf, int count, int interruptible)
371 {
372 	int ret = 0;
373 	int len;
374 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
375 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
376 	unsigned long flags;
377 
378 	dev_dbg(&port->dev,
379 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
380 		oob_priv->dp_port_num, count);
381 
382 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
383 	while (count > 0) {
384 		while (oob_priv->dp_write_urb_in_use) {
385 			cond_wait_interruptible_timeout_irqrestore(
386 				&oob_priv->write_wait, DIGI_RETRY_TIMEOUT,
387 				&oob_priv->dp_port_lock, flags);
388 			if (interruptible && signal_pending(current))
389 				return -EINTR;
390 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
391 		}
392 
393 		/* len must be a multiple of 4, so commands are not split */
394 		len = min(count, oob_port->bulk_out_size);
395 		if (len > 4)
396 			len &= ~3;
397 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
398 		oob_port->write_urb->transfer_buffer_length = len;
399 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
400 		if (ret == 0) {
401 			oob_priv->dp_write_urb_in_use = 1;
402 			count -= len;
403 			buf += len;
404 		}
405 	}
406 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
407 	if (ret)
408 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
409 			__func__, ret);
410 	return ret;
411 
412 }
413 
414 
415 /*
416  *  Digi Write In Band Command
417  *
418  *  Write commands on the given port.  Commands are 4
419  *  bytes each, multiple commands can be sent at once, and
420  *  no command will be split across USB packets.  If timeout
421  *  is non-zero, write in band command will return after
422  *  waiting unsuccessfully for the URB status to clear for
423  *  timeout ticks.  Returns 0 if successful, or a negative
424  *  error returned by digi_write.
425  */
426 
427 static int digi_write_inb_command(struct usb_serial_port *port,
428 	unsigned char *buf, int count, unsigned long timeout)
429 {
430 	int ret = 0;
431 	int len;
432 	struct digi_port *priv = usb_get_serial_port_data(port);
433 	unsigned char *data = port->write_urb->transfer_buffer;
434 	unsigned long flags;
435 
436 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
437 		priv->dp_port_num, count);
438 
439 	if (timeout)
440 		timeout += jiffies;
441 	else
442 		timeout = ULONG_MAX;
443 
444 	spin_lock_irqsave(&priv->dp_port_lock, flags);
445 	while (count > 0 && ret == 0) {
446 		while (priv->dp_write_urb_in_use &&
447 		       time_before(jiffies, timeout)) {
448 			cond_wait_interruptible_timeout_irqrestore(
449 				&priv->write_wait, DIGI_RETRY_TIMEOUT,
450 				&priv->dp_port_lock, flags);
451 			if (signal_pending(current))
452 				return -EINTR;
453 			spin_lock_irqsave(&priv->dp_port_lock, flags);
454 		}
455 
456 		/* len must be a multiple of 4 and small enough to */
457 		/* guarantee the write will send buffered data first, */
458 		/* so commands are in order with data and not split */
459 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
460 		if (len > 4)
461 			len &= ~3;
462 
463 		/* write any buffered data first */
464 		if (priv->dp_out_buf_len > 0) {
465 			data[0] = DIGI_CMD_SEND_DATA;
466 			data[1] = priv->dp_out_buf_len;
467 			memcpy(data + 2, priv->dp_out_buf,
468 				priv->dp_out_buf_len);
469 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
470 			port->write_urb->transfer_buffer_length
471 				= priv->dp_out_buf_len + 2 + len;
472 		} else {
473 			memcpy(data, buf, len);
474 			port->write_urb->transfer_buffer_length = len;
475 		}
476 
477 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
478 		if (ret == 0) {
479 			priv->dp_write_urb_in_use = 1;
480 			priv->dp_out_buf_len = 0;
481 			count -= len;
482 			buf += len;
483 		}
484 
485 	}
486 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
487 
488 	if (ret)
489 		dev_err(&port->dev,
490 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
491 			__func__, ret, priv->dp_port_num);
492 	return ret;
493 }
494 
495 
496 /*
497  *  Digi Set Modem Signals
498  *
499  *  Sets or clears DTR and RTS on the port, according to the
500  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
501  *  for the modem_signals argument.  Returns 0 if successful,
502  *  -EINTR if interrupted while sleeping, or a non-zero error
503  *  returned by usb_submit_urb.
504  */
505 
506 static int digi_set_modem_signals(struct usb_serial_port *port,
507 	unsigned int modem_signals, int interruptible)
508 {
509 
510 	int ret;
511 	struct digi_port *port_priv = usb_get_serial_port_data(port);
512 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
513 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
514 	unsigned char *data = oob_port->write_urb->transfer_buffer;
515 	unsigned long flags;
516 
517 	dev_dbg(&port->dev,
518 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
519 		port_priv->dp_port_num, modem_signals);
520 
521 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
522 	spin_lock(&port_priv->dp_port_lock);
523 
524 	while (oob_priv->dp_write_urb_in_use) {
525 		spin_unlock(&port_priv->dp_port_lock);
526 		cond_wait_interruptible_timeout_irqrestore(
527 			&oob_priv->write_wait, DIGI_RETRY_TIMEOUT,
528 			&oob_priv->dp_port_lock, flags);
529 		if (interruptible && signal_pending(current))
530 			return -EINTR;
531 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
532 		spin_lock(&port_priv->dp_port_lock);
533 	}
534 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
535 	data[1] = port_priv->dp_port_num;
536 	data[2] = (modem_signals & TIOCM_DTR) ?
537 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
538 	data[3] = 0;
539 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
540 	data[5] = port_priv->dp_port_num;
541 	data[6] = (modem_signals & TIOCM_RTS) ?
542 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
543 	data[7] = 0;
544 
545 	oob_port->write_urb->transfer_buffer_length = 8;
546 
547 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
548 	if (ret == 0) {
549 		oob_priv->dp_write_urb_in_use = 1;
550 		port_priv->dp_modem_signals &= ~(TIOCM_DTR | TIOCM_RTS);
551 		port_priv->dp_modem_signals |=
552 				modem_signals & (TIOCM_DTR | TIOCM_RTS);
553 	}
554 	spin_unlock(&port_priv->dp_port_lock);
555 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
556 	if (ret)
557 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
558 			__func__, ret);
559 	return ret;
560 }
561 
562 /*
563  *  Digi Transmit Idle
564  *
565  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
566  *  to go idle.  It returns 0 if successful or a negative error.
567  *
568  *  There are race conditions here if more than one process is calling
569  *  digi_transmit_idle on the same port at the same time.  However, this
570  *  is only called from close, and only one process can be in close on a
571  *  port at a time, so its ok.
572  */
573 
574 static int digi_transmit_idle(struct usb_serial_port *port,
575 	unsigned long timeout)
576 {
577 	int ret;
578 	unsigned char buf[2];
579 	struct digi_port *priv = usb_get_serial_port_data(port);
580 	unsigned long flags;
581 
582 	spin_lock_irqsave(&priv->dp_port_lock, flags);
583 	priv->dp_transmit_idle = 0;
584 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
585 
586 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
587 	buf[1] = 0;
588 
589 	timeout += jiffies;
590 
591 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
592 	if (ret != 0)
593 		return ret;
594 
595 	spin_lock_irqsave(&priv->dp_port_lock, flags);
596 
597 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
598 		cond_wait_interruptible_timeout_irqrestore(
599 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
600 			&priv->dp_port_lock, flags);
601 		if (signal_pending(current))
602 			return -EINTR;
603 		spin_lock_irqsave(&priv->dp_port_lock, flags);
604 	}
605 	priv->dp_transmit_idle = 0;
606 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
607 	return 0;
608 
609 }
610 
611 
612 static void digi_rx_throttle(struct tty_struct *tty)
613 {
614 	unsigned long flags;
615 	struct usb_serial_port *port = tty->driver_data;
616 	struct digi_port *priv = usb_get_serial_port_data(port);
617 
618 	/* stop receiving characters by not resubmitting the read urb */
619 	spin_lock_irqsave(&priv->dp_port_lock, flags);
620 	priv->dp_throttled = 1;
621 	priv->dp_throttle_restart = 0;
622 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
623 }
624 
625 
626 static void digi_rx_unthrottle(struct tty_struct *tty)
627 {
628 	int ret = 0;
629 	unsigned long flags;
630 	struct usb_serial_port *port = tty->driver_data;
631 	struct digi_port *priv = usb_get_serial_port_data(port);
632 
633 	spin_lock_irqsave(&priv->dp_port_lock, flags);
634 
635 	/* restart read chain */
636 	if (priv->dp_throttle_restart)
637 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
638 
639 	/* turn throttle off */
640 	priv->dp_throttled = 0;
641 	priv->dp_throttle_restart = 0;
642 
643 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
644 
645 	if (ret)
646 		dev_err(&port->dev,
647 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
648 			__func__, ret, priv->dp_port_num);
649 }
650 
651 
652 static void digi_set_termios(struct tty_struct *tty,
653 			     struct usb_serial_port *port,
654 			     const struct ktermios *old_termios)
655 {
656 	struct digi_port *priv = usb_get_serial_port_data(port);
657 	struct device *dev = &port->dev;
658 	unsigned int iflag = tty->termios.c_iflag;
659 	unsigned int cflag = tty->termios.c_cflag;
660 	unsigned int old_iflag = old_termios->c_iflag;
661 	unsigned int old_cflag = old_termios->c_cflag;
662 	unsigned char buf[32];
663 	unsigned int modem_signals;
664 	int arg, ret;
665 	int i = 0;
666 	speed_t baud;
667 
668 	dev_dbg(dev,
669 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
670 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
671 
672 	/* set baud rate */
673 	baud = tty_get_baud_rate(tty);
674 	if (baud != tty_termios_baud_rate(old_termios)) {
675 		arg = -1;
676 
677 		/* reassert DTR and (maybe) RTS on transition from B0 */
678 		if ((old_cflag & CBAUD) == B0) {
679 			/* don't set RTS if using hardware flow control */
680 			/* and throttling input */
681 			modem_signals = TIOCM_DTR;
682 			if (!C_CRTSCTS(tty) || !tty_throttled(tty))
683 				modem_signals |= TIOCM_RTS;
684 			digi_set_modem_signals(port, modem_signals, 1);
685 		}
686 		switch (baud) {
687 		/* drop DTR and RTS on transition to B0 */
688 		case 0: digi_set_modem_signals(port, 0, 1); break;
689 		case 50: arg = DIGI_BAUD_50; break;
690 		case 75: arg = DIGI_BAUD_75; break;
691 		case 110: arg = DIGI_BAUD_110; break;
692 		case 150: arg = DIGI_BAUD_150; break;
693 		case 200: arg = DIGI_BAUD_200; break;
694 		case 300: arg = DIGI_BAUD_300; break;
695 		case 600: arg = DIGI_BAUD_600; break;
696 		case 1200: arg = DIGI_BAUD_1200; break;
697 		case 1800: arg = DIGI_BAUD_1800; break;
698 		case 2400: arg = DIGI_BAUD_2400; break;
699 		case 4800: arg = DIGI_BAUD_4800; break;
700 		case 9600: arg = DIGI_BAUD_9600; break;
701 		case 19200: arg = DIGI_BAUD_19200; break;
702 		case 38400: arg = DIGI_BAUD_38400; break;
703 		case 57600: arg = DIGI_BAUD_57600; break;
704 		case 115200: arg = DIGI_BAUD_115200; break;
705 		case 230400: arg = DIGI_BAUD_230400; break;
706 		case 460800: arg = DIGI_BAUD_460800; break;
707 		default:
708 			arg = DIGI_BAUD_9600;
709 			baud = 9600;
710 			break;
711 		}
712 		if (arg != -1) {
713 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
714 			buf[i++] = priv->dp_port_num;
715 			buf[i++] = arg;
716 			buf[i++] = 0;
717 		}
718 	}
719 	/* set parity */
720 	tty->termios.c_cflag &= ~CMSPAR;
721 
722 	if ((cflag & (PARENB | PARODD)) != (old_cflag & (PARENB | PARODD))) {
723 		if (cflag & PARENB) {
724 			if (cflag & PARODD)
725 				arg = DIGI_PARITY_ODD;
726 			else
727 				arg = DIGI_PARITY_EVEN;
728 		} else {
729 			arg = DIGI_PARITY_NONE;
730 		}
731 		buf[i++] = DIGI_CMD_SET_PARITY;
732 		buf[i++] = priv->dp_port_num;
733 		buf[i++] = arg;
734 		buf[i++] = 0;
735 	}
736 	/* set word size */
737 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
738 		arg = -1;
739 		switch (cflag & CSIZE) {
740 		case CS5: arg = DIGI_WORD_SIZE_5; break;
741 		case CS6: arg = DIGI_WORD_SIZE_6; break;
742 		case CS7: arg = DIGI_WORD_SIZE_7; break;
743 		case CS8: arg = DIGI_WORD_SIZE_8; break;
744 		default:
745 			dev_dbg(dev,
746 				"digi_set_termios: can't handle word size %d\n",
747 				cflag & CSIZE);
748 			break;
749 		}
750 
751 		if (arg != -1) {
752 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
753 			buf[i++] = priv->dp_port_num;
754 			buf[i++] = arg;
755 			buf[i++] = 0;
756 		}
757 
758 	}
759 
760 	/* set stop bits */
761 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
762 
763 		if ((cflag & CSTOPB))
764 			arg = DIGI_STOP_BITS_2;
765 		else
766 			arg = DIGI_STOP_BITS_1;
767 
768 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
769 		buf[i++] = priv->dp_port_num;
770 		buf[i++] = arg;
771 		buf[i++] = 0;
772 
773 	}
774 
775 	/* set input flow control */
776 	if ((iflag & IXOFF) != (old_iflag & IXOFF) ||
777 			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
778 		arg = 0;
779 		if (iflag & IXOFF)
780 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
781 		else
782 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
783 
784 		if (cflag & CRTSCTS) {
785 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
786 
787 			/* On USB-4 it is necessary to assert RTS prior */
788 			/* to selecting RTS input flow control.  */
789 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
790 			buf[i++] = priv->dp_port_num;
791 			buf[i++] = DIGI_RTS_ACTIVE;
792 			buf[i++] = 0;
793 
794 		} else {
795 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
796 		}
797 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
798 		buf[i++] = priv->dp_port_num;
799 		buf[i++] = arg;
800 		buf[i++] = 0;
801 	}
802 
803 	/* set output flow control */
804 	if ((iflag & IXON) != (old_iflag & IXON) ||
805 			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
806 		arg = 0;
807 		if (iflag & IXON)
808 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
809 		else
810 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
811 
812 		if (cflag & CRTSCTS)
813 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
814 		else
815 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
816 
817 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
818 		buf[i++] = priv->dp_port_num;
819 		buf[i++] = arg;
820 		buf[i++] = 0;
821 	}
822 
823 	/* set receive enable/disable */
824 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
825 		if (cflag & CREAD)
826 			arg = DIGI_ENABLE;
827 		else
828 			arg = DIGI_DISABLE;
829 
830 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
831 		buf[i++] = priv->dp_port_num;
832 		buf[i++] = arg;
833 		buf[i++] = 0;
834 	}
835 	ret = digi_write_oob_command(port, buf, i, 1);
836 	if (ret != 0)
837 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
838 	tty_encode_baud_rate(tty, baud, baud);
839 }
840 
841 
842 static int digi_break_ctl(struct tty_struct *tty, int break_state)
843 {
844 	struct usb_serial_port *port = tty->driver_data;
845 	unsigned char buf[4];
846 
847 	buf[0] = DIGI_CMD_BREAK_CONTROL;
848 	buf[1] = 2;				/* length */
849 	buf[2] = break_state ? 1 : 0;
850 	buf[3] = 0;				/* pad */
851 
852 	return digi_write_inb_command(port, buf, 4, 0);
853 }
854 
855 
856 static int digi_tiocmget(struct tty_struct *tty)
857 {
858 	struct usb_serial_port *port = tty->driver_data;
859 	struct digi_port *priv = usb_get_serial_port_data(port);
860 	unsigned int val;
861 	unsigned long flags;
862 
863 	spin_lock_irqsave(&priv->dp_port_lock, flags);
864 	val = priv->dp_modem_signals;
865 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
866 	return val;
867 }
868 
869 
870 static int digi_tiocmset(struct tty_struct *tty,
871 					unsigned int set, unsigned int clear)
872 {
873 	struct usb_serial_port *port = tty->driver_data;
874 	struct digi_port *priv = usb_get_serial_port_data(port);
875 	unsigned int val;
876 	unsigned long flags;
877 
878 	spin_lock_irqsave(&priv->dp_port_lock, flags);
879 	val = (priv->dp_modem_signals & ~clear) | set;
880 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
881 	return digi_set_modem_signals(port, val, 1);
882 }
883 
884 
885 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
886 					const unsigned char *buf, int count)
887 {
888 
889 	int ret, data_len, new_len;
890 	struct digi_port *priv = usb_get_serial_port_data(port);
891 	unsigned char *data = port->write_urb->transfer_buffer;
892 	unsigned long flags;
893 
894 	dev_dbg(&port->dev, "digi_write: TOP: port=%d, count=%d\n",
895 		priv->dp_port_num, count);
896 
897 	/* copy user data (which can sleep) before getting spin lock */
898 	count = min(count, port->bulk_out_size-2);
899 	count = min(64, count);
900 
901 	/* be sure only one write proceeds at a time */
902 	/* there are races on the port private buffer */
903 	spin_lock_irqsave(&priv->dp_port_lock, flags);
904 
905 	/* wait for urb status clear to submit another urb */
906 	if (priv->dp_write_urb_in_use) {
907 		/* buffer data if count is 1 (probably put_char) if possible */
908 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
909 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
910 			new_len = 1;
911 		} else {
912 			new_len = 0;
913 		}
914 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
915 		return new_len;
916 	}
917 
918 	/* allow space for any buffered data and for new data, up to */
919 	/* transfer buffer size - 2 (for command and length bytes) */
920 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
921 	data_len = new_len + priv->dp_out_buf_len;
922 
923 	if (data_len == 0) {
924 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
925 		return 0;
926 	}
927 
928 	port->write_urb->transfer_buffer_length = data_len+2;
929 
930 	*data++ = DIGI_CMD_SEND_DATA;
931 	*data++ = data_len;
932 
933 	/* copy in buffered data first */
934 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
935 	data += priv->dp_out_buf_len;
936 
937 	/* copy in new data */
938 	memcpy(data, buf, new_len);
939 
940 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
941 	if (ret == 0) {
942 		priv->dp_write_urb_in_use = 1;
943 		ret = new_len;
944 		priv->dp_out_buf_len = 0;
945 	}
946 
947 	/* return length of new data written, or error */
948 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
949 	if (ret < 0)
950 		dev_err_console(port,
951 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
952 			__func__, ret, priv->dp_port_num);
953 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
954 	return ret;
955 
956 }
957 
958 static void digi_write_bulk_callback(struct urb *urb)
959 {
960 
961 	struct usb_serial_port *port = urb->context;
962 	struct usb_serial *serial;
963 	struct digi_port *priv;
964 	struct digi_serial *serial_priv;
965 	unsigned long flags;
966 	int ret = 0;
967 	int status = urb->status;
968 	bool wakeup;
969 
970 	/* port and serial sanity check */
971 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
972 		pr_err("%s: port or port->private is NULL, status=%d\n",
973 			__func__, status);
974 		return;
975 	}
976 	serial = port->serial;
977 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
978 		dev_err(&port->dev,
979 			"%s: serial or serial->private is NULL, status=%d\n",
980 			__func__, status);
981 		return;
982 	}
983 
984 	/* handle oob callback */
985 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
986 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
987 		spin_lock_irqsave(&priv->dp_port_lock, flags);
988 		priv->dp_write_urb_in_use = 0;
989 		wake_up_interruptible(&priv->write_wait);
990 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
991 		return;
992 	}
993 
994 	/* try to send any buffered data on this port */
995 	wakeup = true;
996 	spin_lock_irqsave(&priv->dp_port_lock, flags);
997 	priv->dp_write_urb_in_use = 0;
998 	if (priv->dp_out_buf_len > 0) {
999 		*((unsigned char *)(port->write_urb->transfer_buffer))
1000 			= (unsigned char)DIGI_CMD_SEND_DATA;
1001 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1002 			= (unsigned char)priv->dp_out_buf_len;
1003 		port->write_urb->transfer_buffer_length =
1004 						priv->dp_out_buf_len + 2;
1005 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1006 			priv->dp_out_buf_len);
1007 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1008 		if (ret == 0) {
1009 			priv->dp_write_urb_in_use = 1;
1010 			priv->dp_out_buf_len = 0;
1011 			wakeup = false;
1012 		}
1013 	}
1014 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1015 
1016 	if (ret && ret != -EPERM)
1017 		dev_err_console(port,
1018 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1019 			__func__, ret, priv->dp_port_num);
1020 
1021 	if (wakeup)
1022 		tty_port_tty_wakeup(&port->port);
1023 }
1024 
1025 static unsigned int digi_write_room(struct tty_struct *tty)
1026 {
1027 	struct usb_serial_port *port = tty->driver_data;
1028 	struct digi_port *priv = usb_get_serial_port_data(port);
1029 	unsigned long flags;
1030 	unsigned int room;
1031 
1032 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1033 
1034 	if (priv->dp_write_urb_in_use)
1035 		room = 0;
1036 	else
1037 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1038 
1039 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1040 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%u\n", priv->dp_port_num, room);
1041 	return room;
1042 
1043 }
1044 
1045 static unsigned int digi_chars_in_buffer(struct tty_struct *tty)
1046 {
1047 	struct usb_serial_port *port = tty->driver_data;
1048 	struct digi_port *priv = usb_get_serial_port_data(port);
1049 	unsigned long flags;
1050 	unsigned int chars;
1051 
1052 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1053 	if (priv->dp_write_urb_in_use)
1054 		chars = port->bulk_out_size - 2;
1055 	else
1056 		chars = priv->dp_out_buf_len;
1057 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1058 
1059 	dev_dbg(&port->dev, "%s: port=%d, chars=%d\n", __func__,
1060 			priv->dp_port_num, chars);
1061 	return chars;
1062 }
1063 
1064 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1065 {
1066 	/* Adjust DTR and RTS */
1067 	digi_set_modem_signals(port, on * (TIOCM_DTR | TIOCM_RTS), 1);
1068 }
1069 
1070 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1071 {
1072 	int ret;
1073 	unsigned char buf[32];
1074 	struct digi_port *priv = usb_get_serial_port_data(port);
1075 	struct ktermios not_termios;
1076 
1077 	/* be sure the device is started up */
1078 	if (digi_startup_device(port->serial) != 0)
1079 		return -ENXIO;
1080 
1081 	/* read modem signals automatically whenever they change */
1082 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1083 	buf[1] = priv->dp_port_num;
1084 	buf[2] = DIGI_ENABLE;
1085 	buf[3] = 0;
1086 
1087 	/* flush fifos */
1088 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1089 	buf[5] = priv->dp_port_num;
1090 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1091 	buf[7] = 0;
1092 
1093 	ret = digi_write_oob_command(port, buf, 8, 1);
1094 	if (ret != 0)
1095 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1096 
1097 	/* set termios settings */
1098 	if (tty) {
1099 		not_termios.c_cflag = ~tty->termios.c_cflag;
1100 		not_termios.c_iflag = ~tty->termios.c_iflag;
1101 		digi_set_termios(tty, port, &not_termios);
1102 	}
1103 	return 0;
1104 }
1105 
1106 
1107 static void digi_close(struct usb_serial_port *port)
1108 {
1109 	DEFINE_WAIT(wait);
1110 	int ret;
1111 	unsigned char buf[32];
1112 	struct digi_port *priv = usb_get_serial_port_data(port);
1113 
1114 	mutex_lock(&port->serial->disc_mutex);
1115 	/* if disconnected, just clear flags */
1116 	if (port->serial->disconnected)
1117 		goto exit;
1118 
1119 	/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1120 	digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1121 
1122 	/* disable input flow control */
1123 	buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1124 	buf[1] = priv->dp_port_num;
1125 	buf[2] = DIGI_DISABLE;
1126 	buf[3] = 0;
1127 
1128 	/* disable output flow control */
1129 	buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1130 	buf[5] = priv->dp_port_num;
1131 	buf[6] = DIGI_DISABLE;
1132 	buf[7] = 0;
1133 
1134 	/* disable reading modem signals automatically */
1135 	buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1136 	buf[9] = priv->dp_port_num;
1137 	buf[10] = DIGI_DISABLE;
1138 	buf[11] = 0;
1139 
1140 	/* disable receive */
1141 	buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1142 	buf[13] = priv->dp_port_num;
1143 	buf[14] = DIGI_DISABLE;
1144 	buf[15] = 0;
1145 
1146 	/* flush fifos */
1147 	buf[16] = DIGI_CMD_IFLUSH_FIFO;
1148 	buf[17] = priv->dp_port_num;
1149 	buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1150 	buf[19] = 0;
1151 
1152 	ret = digi_write_oob_command(port, buf, 20, 0);
1153 	if (ret != 0)
1154 		dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n",
1155 									ret);
1156 	/* wait for final commands on oob port to complete */
1157 	prepare_to_wait(&priv->dp_flush_wait, &wait,
1158 			TASK_INTERRUPTIBLE);
1159 	schedule_timeout(DIGI_CLOSE_TIMEOUT);
1160 	finish_wait(&priv->dp_flush_wait, &wait);
1161 
1162 	/* shutdown any outstanding bulk writes */
1163 	usb_kill_urb(port->write_urb);
1164 exit:
1165 	spin_lock_irq(&priv->dp_port_lock);
1166 	priv->dp_write_urb_in_use = 0;
1167 	wake_up_interruptible(&priv->dp_close_wait);
1168 	spin_unlock_irq(&priv->dp_port_lock);
1169 	mutex_unlock(&port->serial->disc_mutex);
1170 }
1171 
1172 
1173 /*
1174  *  Digi Startup Device
1175  *
1176  *  Starts reads on all ports.  Must be called AFTER startup, with
1177  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1178  */
1179 
1180 static int digi_startup_device(struct usb_serial *serial)
1181 {
1182 	int i, ret = 0;
1183 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1184 	struct usb_serial_port *port;
1185 
1186 	/* be sure this happens exactly once */
1187 	spin_lock(&serial_priv->ds_serial_lock);
1188 	if (serial_priv->ds_device_started) {
1189 		spin_unlock(&serial_priv->ds_serial_lock);
1190 		return 0;
1191 	}
1192 	serial_priv->ds_device_started = 1;
1193 	spin_unlock(&serial_priv->ds_serial_lock);
1194 
1195 	/* start reading from each bulk in endpoint for the device */
1196 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1197 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1198 		port = serial->port[i];
1199 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1200 		if (ret != 0) {
1201 			dev_err(&port->dev,
1202 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1203 				__func__, ret, i);
1204 			break;
1205 		}
1206 	}
1207 	return ret;
1208 }
1209 
1210 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1211 {
1212 	struct digi_port *priv;
1213 
1214 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1215 	if (!priv)
1216 		return -ENOMEM;
1217 
1218 	spin_lock_init(&priv->dp_port_lock);
1219 	priv->dp_port_num = port_num;
1220 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1221 	init_waitqueue_head(&priv->dp_flush_wait);
1222 	init_waitqueue_head(&priv->dp_close_wait);
1223 	init_waitqueue_head(&priv->write_wait);
1224 	priv->dp_port = port;
1225 
1226 	usb_set_serial_port_data(port, priv);
1227 
1228 	return 0;
1229 }
1230 
1231 static int digi_startup(struct usb_serial *serial)
1232 {
1233 	struct digi_serial *serial_priv;
1234 	int ret;
1235 
1236 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1237 	if (!serial_priv)
1238 		return -ENOMEM;
1239 
1240 	spin_lock_init(&serial_priv->ds_serial_lock);
1241 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1242 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1243 
1244 	ret = digi_port_init(serial_priv->ds_oob_port,
1245 						serial_priv->ds_oob_port_num);
1246 	if (ret) {
1247 		kfree(serial_priv);
1248 		return ret;
1249 	}
1250 
1251 	usb_set_serial_data(serial, serial_priv);
1252 
1253 	return 0;
1254 }
1255 
1256 
1257 static void digi_disconnect(struct usb_serial *serial)
1258 {
1259 	int i;
1260 
1261 	/* stop reads and writes on all ports */
1262 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1263 		usb_kill_urb(serial->port[i]->read_urb);
1264 		usb_kill_urb(serial->port[i]->write_urb);
1265 	}
1266 }
1267 
1268 
1269 static void digi_release(struct usb_serial *serial)
1270 {
1271 	struct digi_serial *serial_priv;
1272 	struct digi_port *priv;
1273 
1274 	serial_priv = usb_get_serial_data(serial);
1275 
1276 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1277 	kfree(priv);
1278 
1279 	kfree(serial_priv);
1280 }
1281 
1282 static int digi_port_probe(struct usb_serial_port *port)
1283 {
1284 	return digi_port_init(port, port->port_number);
1285 }
1286 
1287 static void digi_port_remove(struct usb_serial_port *port)
1288 {
1289 	struct digi_port *priv;
1290 
1291 	priv = usb_get_serial_port_data(port);
1292 	kfree(priv);
1293 }
1294 
1295 static void digi_read_bulk_callback(struct urb *urb)
1296 {
1297 	struct usb_serial_port *port = urb->context;
1298 	struct digi_port *priv;
1299 	struct digi_serial *serial_priv;
1300 	int ret;
1301 	int status = urb->status;
1302 
1303 	/* port sanity check, do not resubmit if port is not valid */
1304 	if (port == NULL)
1305 		return;
1306 	priv = usb_get_serial_port_data(port);
1307 	if (priv == NULL) {
1308 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1309 			__func__, status);
1310 		return;
1311 	}
1312 	if (port->serial == NULL ||
1313 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1314 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1315 			"is NULL, status=%d\n", __func__, status);
1316 		return;
1317 	}
1318 
1319 	/* do not resubmit urb if it has any status error */
1320 	if (status) {
1321 		dev_err(&port->dev,
1322 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1323 			__func__, status, priv->dp_port_num);
1324 		return;
1325 	}
1326 
1327 	/* handle oob or inb callback, do not resubmit if error */
1328 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1329 		if (digi_read_oob_callback(urb) != 0)
1330 			return;
1331 	} else {
1332 		if (digi_read_inb_callback(urb) != 0)
1333 			return;
1334 	}
1335 
1336 	/* continue read */
1337 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1338 	if (ret != 0 && ret != -EPERM) {
1339 		dev_err(&port->dev,
1340 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1341 			__func__, ret, priv->dp_port_num);
1342 	}
1343 
1344 }
1345 
1346 /*
1347  *  Digi Read INB Callback
1348  *
1349  *  Digi Read INB Callback handles reads on the in band ports, sending
1350  *  the data on to the tty subsystem.  When called we know port and
1351  *  port->private are not NULL and port->serial has been validated.
1352  *  It returns 0 if successful, 1 if successful but the port is
1353  *  throttled, and -1 if the sanity checks failed.
1354  */
1355 
1356 static int digi_read_inb_callback(struct urb *urb)
1357 {
1358 	struct usb_serial_port *port = urb->context;
1359 	struct digi_port *priv = usb_get_serial_port_data(port);
1360 	unsigned char *buf = urb->transfer_buffer;
1361 	unsigned long flags;
1362 	int opcode;
1363 	int len;
1364 	int port_status;
1365 	unsigned char *data;
1366 	int tty_flag, throttled;
1367 
1368 	/* short/multiple packet check */
1369 	if (urb->actual_length < 2) {
1370 		dev_warn(&port->dev, "short packet received\n");
1371 		return -1;
1372 	}
1373 
1374 	opcode = buf[0];
1375 	len = buf[1];
1376 
1377 	if (urb->actual_length != len + 2) {
1378 		dev_err(&port->dev, "malformed packet received: port=%d, opcode=%d, len=%d, actual_length=%u\n",
1379 			priv->dp_port_num, opcode, len, urb->actual_length);
1380 		return -1;
1381 	}
1382 
1383 	if (opcode == DIGI_CMD_RECEIVE_DATA && len < 1) {
1384 		dev_err(&port->dev, "malformed data packet received\n");
1385 		return -1;
1386 	}
1387 
1388 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1389 
1390 	/* check for throttle; if set, do not resubmit read urb */
1391 	/* indicate the read chain needs to be restarted on unthrottle */
1392 	throttled = priv->dp_throttled;
1393 	if (throttled)
1394 		priv->dp_throttle_restart = 1;
1395 
1396 	/* receive data */
1397 	if (opcode == DIGI_CMD_RECEIVE_DATA) {
1398 		port_status = buf[2];
1399 		data = &buf[3];
1400 
1401 		/* get flag from port_status */
1402 		tty_flag = 0;
1403 
1404 		/* overrun is special, not associated with a char */
1405 		if (port_status & DIGI_OVERRUN_ERROR)
1406 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1407 
1408 		/* break takes precedence over parity, */
1409 		/* which takes precedence over framing errors */
1410 		if (port_status & DIGI_BREAK_ERROR)
1411 			tty_flag = TTY_BREAK;
1412 		else if (port_status & DIGI_PARITY_ERROR)
1413 			tty_flag = TTY_PARITY;
1414 		else if (port_status & DIGI_FRAMING_ERROR)
1415 			tty_flag = TTY_FRAME;
1416 
1417 		/* data length is len-1 (one byte of len is port_status) */
1418 		--len;
1419 		if (len > 0) {
1420 			tty_insert_flip_string_fixed_flag(&port->port, data,
1421 					tty_flag, len);
1422 			tty_flip_buffer_push(&port->port);
1423 		}
1424 	}
1425 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1426 
1427 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1428 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1429 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1430 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1431 
1432 	return throttled ? 1 : 0;
1433 
1434 }
1435 
1436 
1437 /*
1438  *  Digi Read OOB Callback
1439  *
1440  *  Digi Read OOB Callback handles reads on the out of band port.
1441  *  When called we know port and port->private are not NULL and
1442  *  the port->serial is valid.  It returns 0 if successful, and
1443  *  -1 if the sanity checks failed.
1444  */
1445 
1446 static int digi_read_oob_callback(struct urb *urb)
1447 {
1448 
1449 	struct usb_serial_port *port = urb->context;
1450 	struct usb_serial *serial = port->serial;
1451 	struct tty_struct *tty;
1452 	struct digi_port *priv;
1453 	unsigned char *buf = urb->transfer_buffer;
1454 	int opcode, line, status, val;
1455 	unsigned long flags;
1456 	int i;
1457 	unsigned int rts;
1458 
1459 	if (urb->actual_length < 4)
1460 		return -1;
1461 
1462 	/* handle each oob command */
1463 	for (i = 0; i < urb->actual_length - 3; i += 4) {
1464 		opcode = buf[i];
1465 		line = buf[i + 1];
1466 		status = buf[i + 2];
1467 		val = buf[i + 3];
1468 
1469 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1470 			opcode, line, status, val);
1471 
1472 		if (status != 0 || line >= serial->type->num_ports)
1473 			continue;
1474 
1475 		port = serial->port[line];
1476 
1477 		priv = usb_get_serial_port_data(port);
1478 		if (priv == NULL)
1479 			return -1;
1480 
1481 		tty = tty_port_tty_get(&port->port);
1482 
1483 		rts = 0;
1484 		if (tty)
1485 			rts = C_CRTSCTS(tty);
1486 
1487 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1488 			bool wakeup = false;
1489 
1490 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1491 			/* convert from digi flags to termiox flags */
1492 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1493 				priv->dp_modem_signals |= TIOCM_CTS;
1494 				if (rts)
1495 					wakeup = true;
1496 			} else {
1497 				priv->dp_modem_signals &= ~TIOCM_CTS;
1498 				/* port must be open to use tty struct */
1499 			}
1500 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1501 				priv->dp_modem_signals |= TIOCM_DSR;
1502 			else
1503 				priv->dp_modem_signals &= ~TIOCM_DSR;
1504 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1505 				priv->dp_modem_signals |= TIOCM_RI;
1506 			else
1507 				priv->dp_modem_signals &= ~TIOCM_RI;
1508 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1509 				priv->dp_modem_signals |= TIOCM_CD;
1510 			else
1511 				priv->dp_modem_signals &= ~TIOCM_CD;
1512 
1513 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1514 
1515 			if (wakeup)
1516 				tty_port_tty_wakeup(&port->port);
1517 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1518 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1519 			priv->dp_transmit_idle = 1;
1520 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1521 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1522 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1523 			wake_up_interruptible(&priv->dp_flush_wait);
1524 		}
1525 		tty_kref_put(tty);
1526 	}
1527 	return 0;
1528 
1529 }
1530 
1531 module_usb_serial_driver(serial_drivers, id_table_combined);
1532 
1533 MODULE_AUTHOR(DRIVER_AUTHOR);
1534 MODULE_DESCRIPTION(DRIVER_DESC);
1535 MODULE_LICENSE("GPL");
1536