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 void 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 void 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 	digi_write_inb_command(port, buf, 4, 0);
852 }
853 
854 
855 static int digi_tiocmget(struct tty_struct *tty)
856 {
857 	struct usb_serial_port *port = tty->driver_data;
858 	struct digi_port *priv = usb_get_serial_port_data(port);
859 	unsigned int val;
860 	unsigned long flags;
861 
862 	spin_lock_irqsave(&priv->dp_port_lock, flags);
863 	val = priv->dp_modem_signals;
864 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
865 	return val;
866 }
867 
868 
869 static int digi_tiocmset(struct tty_struct *tty,
870 					unsigned int set, unsigned int clear)
871 {
872 	struct usb_serial_port *port = tty->driver_data;
873 	struct digi_port *priv = usb_get_serial_port_data(port);
874 	unsigned int val;
875 	unsigned long flags;
876 
877 	spin_lock_irqsave(&priv->dp_port_lock, flags);
878 	val = (priv->dp_modem_signals & ~clear) | set;
879 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
880 	return digi_set_modem_signals(port, val, 1);
881 }
882 
883 
884 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
885 					const unsigned char *buf, int count)
886 {
887 
888 	int ret, data_len, new_len;
889 	struct digi_port *priv = usb_get_serial_port_data(port);
890 	unsigned char *data = port->write_urb->transfer_buffer;
891 	unsigned long flags;
892 
893 	dev_dbg(&port->dev, "digi_write: TOP: port=%d, count=%d\n",
894 		priv->dp_port_num, count);
895 
896 	/* copy user data (which can sleep) before getting spin lock */
897 	count = min(count, port->bulk_out_size-2);
898 	count = min(64, count);
899 
900 	/* be sure only one write proceeds at a time */
901 	/* there are races on the port private buffer */
902 	spin_lock_irqsave(&priv->dp_port_lock, flags);
903 
904 	/* wait for urb status clear to submit another urb */
905 	if (priv->dp_write_urb_in_use) {
906 		/* buffer data if count is 1 (probably put_char) if possible */
907 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
908 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
909 			new_len = 1;
910 		} else {
911 			new_len = 0;
912 		}
913 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
914 		return new_len;
915 	}
916 
917 	/* allow space for any buffered data and for new data, up to */
918 	/* transfer buffer size - 2 (for command and length bytes) */
919 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
920 	data_len = new_len + priv->dp_out_buf_len;
921 
922 	if (data_len == 0) {
923 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
924 		return 0;
925 	}
926 
927 	port->write_urb->transfer_buffer_length = data_len+2;
928 
929 	*data++ = DIGI_CMD_SEND_DATA;
930 	*data++ = data_len;
931 
932 	/* copy in buffered data first */
933 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
934 	data += priv->dp_out_buf_len;
935 
936 	/* copy in new data */
937 	memcpy(data, buf, new_len);
938 
939 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
940 	if (ret == 0) {
941 		priv->dp_write_urb_in_use = 1;
942 		ret = new_len;
943 		priv->dp_out_buf_len = 0;
944 	}
945 
946 	/* return length of new data written, or error */
947 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
948 	if (ret < 0)
949 		dev_err_console(port,
950 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
951 			__func__, ret, priv->dp_port_num);
952 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
953 	return ret;
954 
955 }
956 
957 static void digi_write_bulk_callback(struct urb *urb)
958 {
959 
960 	struct usb_serial_port *port = urb->context;
961 	struct usb_serial *serial;
962 	struct digi_port *priv;
963 	struct digi_serial *serial_priv;
964 	unsigned long flags;
965 	int ret = 0;
966 	int status = urb->status;
967 	bool wakeup;
968 
969 	/* port and serial sanity check */
970 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
971 		pr_err("%s: port or port->private is NULL, status=%d\n",
972 			__func__, status);
973 		return;
974 	}
975 	serial = port->serial;
976 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
977 		dev_err(&port->dev,
978 			"%s: serial or serial->private is NULL, status=%d\n",
979 			__func__, status);
980 		return;
981 	}
982 
983 	/* handle oob callback */
984 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
985 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
986 		spin_lock_irqsave(&priv->dp_port_lock, flags);
987 		priv->dp_write_urb_in_use = 0;
988 		wake_up_interruptible(&priv->write_wait);
989 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
990 		return;
991 	}
992 
993 	/* try to send any buffered data on this port */
994 	wakeup = true;
995 	spin_lock_irqsave(&priv->dp_port_lock, flags);
996 	priv->dp_write_urb_in_use = 0;
997 	if (priv->dp_out_buf_len > 0) {
998 		*((unsigned char *)(port->write_urb->transfer_buffer))
999 			= (unsigned char)DIGI_CMD_SEND_DATA;
1000 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1001 			= (unsigned char)priv->dp_out_buf_len;
1002 		port->write_urb->transfer_buffer_length =
1003 						priv->dp_out_buf_len + 2;
1004 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1005 			priv->dp_out_buf_len);
1006 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1007 		if (ret == 0) {
1008 			priv->dp_write_urb_in_use = 1;
1009 			priv->dp_out_buf_len = 0;
1010 			wakeup = false;
1011 		}
1012 	}
1013 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1014 
1015 	if (ret && ret != -EPERM)
1016 		dev_err_console(port,
1017 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1018 			__func__, ret, priv->dp_port_num);
1019 
1020 	if (wakeup)
1021 		tty_port_tty_wakeup(&port->port);
1022 }
1023 
1024 static unsigned int digi_write_room(struct tty_struct *tty)
1025 {
1026 	struct usb_serial_port *port = tty->driver_data;
1027 	struct digi_port *priv = usb_get_serial_port_data(port);
1028 	unsigned long flags;
1029 	unsigned int room;
1030 
1031 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1032 
1033 	if (priv->dp_write_urb_in_use)
1034 		room = 0;
1035 	else
1036 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1037 
1038 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1039 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%u\n", priv->dp_port_num, room);
1040 	return room;
1041 
1042 }
1043 
1044 static unsigned int digi_chars_in_buffer(struct tty_struct *tty)
1045 {
1046 	struct usb_serial_port *port = tty->driver_data;
1047 	struct digi_port *priv = usb_get_serial_port_data(port);
1048 	unsigned long flags;
1049 	unsigned int chars;
1050 
1051 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1052 	if (priv->dp_write_urb_in_use)
1053 		chars = port->bulk_out_size - 2;
1054 	else
1055 		chars = priv->dp_out_buf_len;
1056 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1057 
1058 	dev_dbg(&port->dev, "%s: port=%d, chars=%d\n", __func__,
1059 			priv->dp_port_num, chars);
1060 	return chars;
1061 }
1062 
1063 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1064 {
1065 	/* Adjust DTR and RTS */
1066 	digi_set_modem_signals(port, on * (TIOCM_DTR | TIOCM_RTS), 1);
1067 }
1068 
1069 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1070 {
1071 	int ret;
1072 	unsigned char buf[32];
1073 	struct digi_port *priv = usb_get_serial_port_data(port);
1074 	struct ktermios not_termios;
1075 
1076 	/* be sure the device is started up */
1077 	if (digi_startup_device(port->serial) != 0)
1078 		return -ENXIO;
1079 
1080 	/* read modem signals automatically whenever they change */
1081 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1082 	buf[1] = priv->dp_port_num;
1083 	buf[2] = DIGI_ENABLE;
1084 	buf[3] = 0;
1085 
1086 	/* flush fifos */
1087 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1088 	buf[5] = priv->dp_port_num;
1089 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1090 	buf[7] = 0;
1091 
1092 	ret = digi_write_oob_command(port, buf, 8, 1);
1093 	if (ret != 0)
1094 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1095 
1096 	/* set termios settings */
1097 	if (tty) {
1098 		not_termios.c_cflag = ~tty->termios.c_cflag;
1099 		not_termios.c_iflag = ~tty->termios.c_iflag;
1100 		digi_set_termios(tty, port, &not_termios);
1101 	}
1102 	return 0;
1103 }
1104 
1105 
1106 static void digi_close(struct usb_serial_port *port)
1107 {
1108 	DEFINE_WAIT(wait);
1109 	int ret;
1110 	unsigned char buf[32];
1111 	struct digi_port *priv = usb_get_serial_port_data(port);
1112 
1113 	mutex_lock(&port->serial->disc_mutex);
1114 	/* if disconnected, just clear flags */
1115 	if (port->serial->disconnected)
1116 		goto exit;
1117 
1118 	/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1119 	digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1120 
1121 	/* disable input flow control */
1122 	buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1123 	buf[1] = priv->dp_port_num;
1124 	buf[2] = DIGI_DISABLE;
1125 	buf[3] = 0;
1126 
1127 	/* disable output flow control */
1128 	buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1129 	buf[5] = priv->dp_port_num;
1130 	buf[6] = DIGI_DISABLE;
1131 	buf[7] = 0;
1132 
1133 	/* disable reading modem signals automatically */
1134 	buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1135 	buf[9] = priv->dp_port_num;
1136 	buf[10] = DIGI_DISABLE;
1137 	buf[11] = 0;
1138 
1139 	/* disable receive */
1140 	buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1141 	buf[13] = priv->dp_port_num;
1142 	buf[14] = DIGI_DISABLE;
1143 	buf[15] = 0;
1144 
1145 	/* flush fifos */
1146 	buf[16] = DIGI_CMD_IFLUSH_FIFO;
1147 	buf[17] = priv->dp_port_num;
1148 	buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1149 	buf[19] = 0;
1150 
1151 	ret = digi_write_oob_command(port, buf, 20, 0);
1152 	if (ret != 0)
1153 		dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n",
1154 									ret);
1155 	/* wait for final commands on oob port to complete */
1156 	prepare_to_wait(&priv->dp_flush_wait, &wait,
1157 			TASK_INTERRUPTIBLE);
1158 	schedule_timeout(DIGI_CLOSE_TIMEOUT);
1159 	finish_wait(&priv->dp_flush_wait, &wait);
1160 
1161 	/* shutdown any outstanding bulk writes */
1162 	usb_kill_urb(port->write_urb);
1163 exit:
1164 	spin_lock_irq(&priv->dp_port_lock);
1165 	priv->dp_write_urb_in_use = 0;
1166 	wake_up_interruptible(&priv->dp_close_wait);
1167 	spin_unlock_irq(&priv->dp_port_lock);
1168 	mutex_unlock(&port->serial->disc_mutex);
1169 }
1170 
1171 
1172 /*
1173  *  Digi Startup Device
1174  *
1175  *  Starts reads on all ports.  Must be called AFTER startup, with
1176  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1177  */
1178 
1179 static int digi_startup_device(struct usb_serial *serial)
1180 {
1181 	int i, ret = 0;
1182 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1183 	struct usb_serial_port *port;
1184 
1185 	/* be sure this happens exactly once */
1186 	spin_lock(&serial_priv->ds_serial_lock);
1187 	if (serial_priv->ds_device_started) {
1188 		spin_unlock(&serial_priv->ds_serial_lock);
1189 		return 0;
1190 	}
1191 	serial_priv->ds_device_started = 1;
1192 	spin_unlock(&serial_priv->ds_serial_lock);
1193 
1194 	/* start reading from each bulk in endpoint for the device */
1195 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1196 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1197 		port = serial->port[i];
1198 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1199 		if (ret != 0) {
1200 			dev_err(&port->dev,
1201 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1202 				__func__, ret, i);
1203 			break;
1204 		}
1205 	}
1206 	return ret;
1207 }
1208 
1209 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1210 {
1211 	struct digi_port *priv;
1212 
1213 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1214 	if (!priv)
1215 		return -ENOMEM;
1216 
1217 	spin_lock_init(&priv->dp_port_lock);
1218 	priv->dp_port_num = port_num;
1219 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1220 	init_waitqueue_head(&priv->dp_flush_wait);
1221 	init_waitqueue_head(&priv->dp_close_wait);
1222 	init_waitqueue_head(&priv->write_wait);
1223 	priv->dp_port = port;
1224 
1225 	usb_set_serial_port_data(port, priv);
1226 
1227 	return 0;
1228 }
1229 
1230 static int digi_startup(struct usb_serial *serial)
1231 {
1232 	struct digi_serial *serial_priv;
1233 	int ret;
1234 
1235 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1236 	if (!serial_priv)
1237 		return -ENOMEM;
1238 
1239 	spin_lock_init(&serial_priv->ds_serial_lock);
1240 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1241 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1242 
1243 	ret = digi_port_init(serial_priv->ds_oob_port,
1244 						serial_priv->ds_oob_port_num);
1245 	if (ret) {
1246 		kfree(serial_priv);
1247 		return ret;
1248 	}
1249 
1250 	usb_set_serial_data(serial, serial_priv);
1251 
1252 	return 0;
1253 }
1254 
1255 
1256 static void digi_disconnect(struct usb_serial *serial)
1257 {
1258 	int i;
1259 
1260 	/* stop reads and writes on all ports */
1261 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1262 		usb_kill_urb(serial->port[i]->read_urb);
1263 		usb_kill_urb(serial->port[i]->write_urb);
1264 	}
1265 }
1266 
1267 
1268 static void digi_release(struct usb_serial *serial)
1269 {
1270 	struct digi_serial *serial_priv;
1271 	struct digi_port *priv;
1272 
1273 	serial_priv = usb_get_serial_data(serial);
1274 
1275 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1276 	kfree(priv);
1277 
1278 	kfree(serial_priv);
1279 }
1280 
1281 static int digi_port_probe(struct usb_serial_port *port)
1282 {
1283 	return digi_port_init(port, port->port_number);
1284 }
1285 
1286 static void digi_port_remove(struct usb_serial_port *port)
1287 {
1288 	struct digi_port *priv;
1289 
1290 	priv = usb_get_serial_port_data(port);
1291 	kfree(priv);
1292 }
1293 
1294 static void digi_read_bulk_callback(struct urb *urb)
1295 {
1296 	struct usb_serial_port *port = urb->context;
1297 	struct digi_port *priv;
1298 	struct digi_serial *serial_priv;
1299 	int ret;
1300 	int status = urb->status;
1301 
1302 	/* port sanity check, do not resubmit if port is not valid */
1303 	if (port == NULL)
1304 		return;
1305 	priv = usb_get_serial_port_data(port);
1306 	if (priv == NULL) {
1307 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1308 			__func__, status);
1309 		return;
1310 	}
1311 	if (port->serial == NULL ||
1312 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1313 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1314 			"is NULL, status=%d\n", __func__, status);
1315 		return;
1316 	}
1317 
1318 	/* do not resubmit urb if it has any status error */
1319 	if (status) {
1320 		dev_err(&port->dev,
1321 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1322 			__func__, status, priv->dp_port_num);
1323 		return;
1324 	}
1325 
1326 	/* handle oob or inb callback, do not resubmit if error */
1327 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1328 		if (digi_read_oob_callback(urb) != 0)
1329 			return;
1330 	} else {
1331 		if (digi_read_inb_callback(urb) != 0)
1332 			return;
1333 	}
1334 
1335 	/* continue read */
1336 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1337 	if (ret != 0 && ret != -EPERM) {
1338 		dev_err(&port->dev,
1339 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1340 			__func__, ret, priv->dp_port_num);
1341 	}
1342 
1343 }
1344 
1345 /*
1346  *  Digi Read INB Callback
1347  *
1348  *  Digi Read INB Callback handles reads on the in band ports, sending
1349  *  the data on to the tty subsystem.  When called we know port and
1350  *  port->private are not NULL and port->serial has been validated.
1351  *  It returns 0 if successful, 1 if successful but the port is
1352  *  throttled, and -1 if the sanity checks failed.
1353  */
1354 
1355 static int digi_read_inb_callback(struct urb *urb)
1356 {
1357 	struct usb_serial_port *port = urb->context;
1358 	struct digi_port *priv = usb_get_serial_port_data(port);
1359 	unsigned char *buf = urb->transfer_buffer;
1360 	unsigned long flags;
1361 	int opcode;
1362 	int len;
1363 	int port_status;
1364 	unsigned char *data;
1365 	int tty_flag, throttled;
1366 
1367 	/* short/multiple packet check */
1368 	if (urb->actual_length < 2) {
1369 		dev_warn(&port->dev, "short packet received\n");
1370 		return -1;
1371 	}
1372 
1373 	opcode = buf[0];
1374 	len = buf[1];
1375 
1376 	if (urb->actual_length != len + 2) {
1377 		dev_err(&port->dev, "malformed packet received: port=%d, opcode=%d, len=%d, actual_length=%u\n",
1378 			priv->dp_port_num, opcode, len, urb->actual_length);
1379 		return -1;
1380 	}
1381 
1382 	if (opcode == DIGI_CMD_RECEIVE_DATA && len < 1) {
1383 		dev_err(&port->dev, "malformed data packet received\n");
1384 		return -1;
1385 	}
1386 
1387 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1388 
1389 	/* check for throttle; if set, do not resubmit read urb */
1390 	/* indicate the read chain needs to be restarted on unthrottle */
1391 	throttled = priv->dp_throttled;
1392 	if (throttled)
1393 		priv->dp_throttle_restart = 1;
1394 
1395 	/* receive data */
1396 	if (opcode == DIGI_CMD_RECEIVE_DATA) {
1397 		port_status = buf[2];
1398 		data = &buf[3];
1399 
1400 		/* get flag from port_status */
1401 		tty_flag = 0;
1402 
1403 		/* overrun is special, not associated with a char */
1404 		if (port_status & DIGI_OVERRUN_ERROR)
1405 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1406 
1407 		/* break takes precedence over parity, */
1408 		/* which takes precedence over framing errors */
1409 		if (port_status & DIGI_BREAK_ERROR)
1410 			tty_flag = TTY_BREAK;
1411 		else if (port_status & DIGI_PARITY_ERROR)
1412 			tty_flag = TTY_PARITY;
1413 		else if (port_status & DIGI_FRAMING_ERROR)
1414 			tty_flag = TTY_FRAME;
1415 
1416 		/* data length is len-1 (one byte of len is port_status) */
1417 		--len;
1418 		if (len > 0) {
1419 			tty_insert_flip_string_fixed_flag(&port->port, data,
1420 					tty_flag, len);
1421 			tty_flip_buffer_push(&port->port);
1422 		}
1423 	}
1424 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1425 
1426 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1427 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1428 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1429 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1430 
1431 	return throttled ? 1 : 0;
1432 
1433 }
1434 
1435 
1436 /*
1437  *  Digi Read OOB Callback
1438  *
1439  *  Digi Read OOB Callback handles reads on the out of band port.
1440  *  When called we know port and port->private are not NULL and
1441  *  the port->serial is valid.  It returns 0 if successful, and
1442  *  -1 if the sanity checks failed.
1443  */
1444 
1445 static int digi_read_oob_callback(struct urb *urb)
1446 {
1447 
1448 	struct usb_serial_port *port = urb->context;
1449 	struct usb_serial *serial = port->serial;
1450 	struct tty_struct *tty;
1451 	struct digi_port *priv;
1452 	unsigned char *buf = urb->transfer_buffer;
1453 	int opcode, line, status, val;
1454 	unsigned long flags;
1455 	int i;
1456 	unsigned int rts;
1457 
1458 	if (urb->actual_length < 4)
1459 		return -1;
1460 
1461 	/* handle each oob command */
1462 	for (i = 0; i < urb->actual_length - 3; i += 4) {
1463 		opcode = buf[i];
1464 		line = buf[i + 1];
1465 		status = buf[i + 2];
1466 		val = buf[i + 3];
1467 
1468 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1469 			opcode, line, status, val);
1470 
1471 		if (status != 0 || line >= serial->type->num_ports)
1472 			continue;
1473 
1474 		port = serial->port[line];
1475 
1476 		priv = usb_get_serial_port_data(port);
1477 		if (priv == NULL)
1478 			return -1;
1479 
1480 		tty = tty_port_tty_get(&port->port);
1481 
1482 		rts = 0;
1483 		if (tty)
1484 			rts = C_CRTSCTS(tty);
1485 
1486 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1487 			bool wakeup = false;
1488 
1489 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1490 			/* convert from digi flags to termiox flags */
1491 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1492 				priv->dp_modem_signals |= TIOCM_CTS;
1493 				if (rts)
1494 					wakeup = true;
1495 			} else {
1496 				priv->dp_modem_signals &= ~TIOCM_CTS;
1497 				/* port must be open to use tty struct */
1498 			}
1499 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1500 				priv->dp_modem_signals |= TIOCM_DSR;
1501 			else
1502 				priv->dp_modem_signals &= ~TIOCM_DSR;
1503 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1504 				priv->dp_modem_signals |= TIOCM_RI;
1505 			else
1506 				priv->dp_modem_signals &= ~TIOCM_RI;
1507 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1508 				priv->dp_modem_signals |= TIOCM_CD;
1509 			else
1510 				priv->dp_modem_signals &= ~TIOCM_CD;
1511 
1512 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1513 
1514 			if (wakeup)
1515 				tty_port_tty_wakeup(&port->port);
1516 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1517 			spin_lock_irqsave(&priv->dp_port_lock, flags);
1518 			priv->dp_transmit_idle = 1;
1519 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1520 			spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1521 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1522 			wake_up_interruptible(&priv->dp_flush_wait);
1523 		}
1524 		tty_kref_put(tty);
1525 	}
1526 	return 0;
1527 
1528 }
1529 
1530 module_usb_serial_driver(serial_drivers, id_table_combined);
1531 
1532 MODULE_AUTHOR(DRIVER_AUTHOR);
1533 MODULE_DESCRIPTION(DRIVER_DESC);
1534 MODULE_LICENSE("GPL");
1535