xref: /linux/drivers/usb/serial/digi_acceleport.c (revision 08ec212c0f92cbf30e3ecc7349f18151714041d6)
1 /*
2 *  Digi AccelePort USB-4 and USB-2 Serial Converters
3 *
4 *  Copyright 2000 by Digi International
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  Shamelessly based on Brian Warner's keyspan_pda.c and Greg Kroah-Hartman's
12 *  usb-serial driver.
13 *
14 *  Peter Berger (pberger@brimson.com)
15 *  Al Borchers (borchers@steinerpoint.com)
16 */
17 
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/tty_driver.h>
24 #include <linux/tty_flip.h>
25 #include <linux/module.h>
26 #include <linux/spinlock.h>
27 #include <linux/workqueue.h>
28 #include <linux/uaccess.h>
29 #include <linux/usb.h>
30 #include <linux/wait.h>
31 #include <linux/usb/serial.h>
32 
33 /* Defines */
34 
35 /*
36  * Version Information
37  */
38 #define DRIVER_VERSION "v1.80.1.2"
39 #define DRIVER_AUTHOR "Peter Berger <pberger@brimson.com>, Al Borchers <borchers@steinerpoint.com>"
40 #define DRIVER_DESC "Digi AccelePort USB-2/USB-4 Serial Converter driver"
41 
42 /* port output buffer length -- must be <= transfer buffer length - 2 */
43 /* so we can be sure to send the full buffer in one urb */
44 #define DIGI_OUT_BUF_SIZE		8
45 
46 /* port input buffer length -- must be >= transfer buffer length - 3 */
47 /* so we can be sure to hold at least one full buffer from one urb */
48 #define DIGI_IN_BUF_SIZE		64
49 
50 /* retry timeout while sleeping */
51 #define DIGI_RETRY_TIMEOUT		(HZ/10)
52 
53 /* timeout while waiting for tty output to drain in close */
54 /* this delay is used twice in close, so the total delay could */
55 /* be twice this value */
56 #define DIGI_CLOSE_TIMEOUT		(5*HZ)
57 
58 
59 /* AccelePort USB Defines */
60 
61 /* ids */
62 #define DIGI_VENDOR_ID			0x05c5
63 #define DIGI_2_ID			0x0002	/* USB-2 */
64 #define DIGI_4_ID			0x0004	/* USB-4 */
65 
66 /* commands
67  * "INB": can be used on the in-band endpoint
68  * "OOB": can be used on the out-of-band endpoint
69  */
70 #define DIGI_CMD_SET_BAUD_RATE			0	/* INB, OOB */
71 #define DIGI_CMD_SET_WORD_SIZE			1	/* INB, OOB */
72 #define DIGI_CMD_SET_PARITY			2	/* INB, OOB */
73 #define DIGI_CMD_SET_STOP_BITS			3	/* INB, OOB */
74 #define DIGI_CMD_SET_INPUT_FLOW_CONTROL		4	/* INB, OOB */
75 #define DIGI_CMD_SET_OUTPUT_FLOW_CONTROL	5	/* INB, OOB */
76 #define DIGI_CMD_SET_DTR_SIGNAL			6	/* INB, OOB */
77 #define DIGI_CMD_SET_RTS_SIGNAL			7	/* INB, OOB */
78 #define DIGI_CMD_READ_INPUT_SIGNALS		8	/*      OOB */
79 #define DIGI_CMD_IFLUSH_FIFO			9	/*      OOB */
80 #define DIGI_CMD_RECEIVE_ENABLE			10	/* INB, OOB */
81 #define DIGI_CMD_BREAK_CONTROL			11	/* INB, OOB */
82 #define DIGI_CMD_LOCAL_LOOPBACK			12	/* INB, OOB */
83 #define DIGI_CMD_TRANSMIT_IDLE			13	/* INB, OOB */
84 #define DIGI_CMD_READ_UART_REGISTER		14	/*      OOB */
85 #define DIGI_CMD_WRITE_UART_REGISTER		15	/* INB, OOB */
86 #define DIGI_CMD_AND_UART_REGISTER		16	/* INB, OOB */
87 #define DIGI_CMD_OR_UART_REGISTER		17	/* INB, OOB */
88 #define DIGI_CMD_SEND_DATA			18	/* INB      */
89 #define DIGI_CMD_RECEIVE_DATA			19	/* INB      */
90 #define DIGI_CMD_RECEIVE_DISABLE		20	/* INB      */
91 #define DIGI_CMD_GET_PORT_TYPE			21	/*      OOB */
92 
93 /* baud rates */
94 #define DIGI_BAUD_50				0
95 #define DIGI_BAUD_75				1
96 #define DIGI_BAUD_110				2
97 #define DIGI_BAUD_150				3
98 #define DIGI_BAUD_200				4
99 #define DIGI_BAUD_300				5
100 #define DIGI_BAUD_600				6
101 #define DIGI_BAUD_1200				7
102 #define DIGI_BAUD_1800				8
103 #define DIGI_BAUD_2400				9
104 #define DIGI_BAUD_4800				10
105 #define DIGI_BAUD_7200				11
106 #define DIGI_BAUD_9600				12
107 #define DIGI_BAUD_14400				13
108 #define DIGI_BAUD_19200				14
109 #define DIGI_BAUD_28800				15
110 #define DIGI_BAUD_38400				16
111 #define DIGI_BAUD_57600				17
112 #define DIGI_BAUD_76800				18
113 #define DIGI_BAUD_115200			19
114 #define DIGI_BAUD_153600			20
115 #define DIGI_BAUD_230400			21
116 #define DIGI_BAUD_460800			22
117 
118 /* arguments */
119 #define DIGI_WORD_SIZE_5			0
120 #define DIGI_WORD_SIZE_6			1
121 #define DIGI_WORD_SIZE_7			2
122 #define DIGI_WORD_SIZE_8			3
123 
124 #define DIGI_PARITY_NONE			0
125 #define DIGI_PARITY_ODD				1
126 #define DIGI_PARITY_EVEN			2
127 #define DIGI_PARITY_MARK			3
128 #define DIGI_PARITY_SPACE			4
129 
130 #define DIGI_STOP_BITS_1			0
131 #define DIGI_STOP_BITS_2			1
132 
133 #define DIGI_INPUT_FLOW_CONTROL_XON_XOFF	1
134 #define DIGI_INPUT_FLOW_CONTROL_RTS		2
135 #define DIGI_INPUT_FLOW_CONTROL_DTR		4
136 
137 #define DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF	1
138 #define DIGI_OUTPUT_FLOW_CONTROL_CTS		2
139 #define DIGI_OUTPUT_FLOW_CONTROL_DSR		4
140 
141 #define DIGI_DTR_INACTIVE			0
142 #define DIGI_DTR_ACTIVE				1
143 #define DIGI_DTR_INPUT_FLOW_CONTROL		2
144 
145 #define DIGI_RTS_INACTIVE			0
146 #define DIGI_RTS_ACTIVE				1
147 #define DIGI_RTS_INPUT_FLOW_CONTROL		2
148 #define DIGI_RTS_TOGGLE				3
149 
150 #define DIGI_FLUSH_TX				1
151 #define DIGI_FLUSH_RX				2
152 #define DIGI_RESUME_TX				4 /* clears xoff condition */
153 
154 #define DIGI_TRANSMIT_NOT_IDLE			0
155 #define DIGI_TRANSMIT_IDLE			1
156 
157 #define DIGI_DISABLE				0
158 #define DIGI_ENABLE				1
159 
160 #define DIGI_DEASSERT				0
161 #define DIGI_ASSERT				1
162 
163 /* in band status codes */
164 #define DIGI_OVERRUN_ERROR			4
165 #define DIGI_PARITY_ERROR			8
166 #define DIGI_FRAMING_ERROR			16
167 #define DIGI_BREAK_ERROR			32
168 
169 /* out of band status */
170 #define DIGI_NO_ERROR				0
171 #define DIGI_BAD_FIRST_PARAMETER		1
172 #define DIGI_BAD_SECOND_PARAMETER		2
173 #define DIGI_INVALID_LINE			3
174 #define DIGI_INVALID_OPCODE			4
175 
176 /* input signals */
177 #define DIGI_READ_INPUT_SIGNALS_SLOT		1
178 #define DIGI_READ_INPUT_SIGNALS_ERR		2
179 #define DIGI_READ_INPUT_SIGNALS_BUSY		4
180 #define DIGI_READ_INPUT_SIGNALS_PE		8
181 #define DIGI_READ_INPUT_SIGNALS_CTS		16
182 #define DIGI_READ_INPUT_SIGNALS_DSR		32
183 #define DIGI_READ_INPUT_SIGNALS_RI		64
184 #define DIGI_READ_INPUT_SIGNALS_DCD		128
185 
186 
187 /* Structures */
188 
189 struct digi_serial {
190 	spinlock_t ds_serial_lock;
191 	struct usb_serial_port *ds_oob_port;	/* out-of-band port */
192 	int ds_oob_port_num;			/* index of out-of-band port */
193 	int ds_device_started;
194 };
195 
196 struct digi_port {
197 	spinlock_t dp_port_lock;
198 	int dp_port_num;
199 	int dp_out_buf_len;
200 	unsigned char dp_out_buf[DIGI_OUT_BUF_SIZE];
201 	int dp_write_urb_in_use;
202 	unsigned int dp_modem_signals;
203 	wait_queue_head_t dp_modem_change_wait;
204 	int dp_transmit_idle;
205 	wait_queue_head_t dp_transmit_idle_wait;
206 	int dp_throttled;
207 	int dp_throttle_restart;
208 	wait_queue_head_t dp_flush_wait;
209 	wait_queue_head_t dp_close_wait;	/* wait queue for close */
210 	struct work_struct dp_wakeup_work;
211 	struct usb_serial_port *dp_port;
212 };
213 
214 
215 /* Local Function Declarations */
216 
217 static void digi_wakeup_write(struct usb_serial_port *port);
218 static void digi_wakeup_write_lock(struct work_struct *work);
219 static int digi_write_oob_command(struct usb_serial_port *port,
220 	unsigned char *buf, int count, int interruptible);
221 static int digi_write_inb_command(struct usb_serial_port *port,
222 	unsigned char *buf, int count, unsigned long timeout);
223 static int digi_set_modem_signals(struct usb_serial_port *port,
224 	unsigned int modem_signals, int interruptible);
225 static int digi_transmit_idle(struct usb_serial_port *port,
226 	unsigned long timeout);
227 static void digi_rx_throttle(struct tty_struct *tty);
228 static void digi_rx_unthrottle(struct tty_struct *tty);
229 static void digi_set_termios(struct tty_struct *tty,
230 		struct usb_serial_port *port, struct ktermios *old_termios);
231 static void digi_break_ctl(struct tty_struct *tty, int break_state);
232 static int digi_tiocmget(struct tty_struct *tty);
233 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
234 		unsigned int clear);
235 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
236 		const unsigned char *buf, int count);
237 static void digi_write_bulk_callback(struct urb *urb);
238 static int digi_write_room(struct tty_struct *tty);
239 static int digi_chars_in_buffer(struct tty_struct *tty);
240 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
241 static void digi_close(struct usb_serial_port *port);
242 static void digi_dtr_rts(struct usb_serial_port *port, int on);
243 static int digi_startup_device(struct usb_serial *serial);
244 static int digi_startup(struct usb_serial *serial);
245 static void digi_disconnect(struct usb_serial *serial);
246 static void digi_release(struct usb_serial *serial);
247 static void digi_read_bulk_callback(struct urb *urb);
248 static int digi_read_inb_callback(struct urb *urb);
249 static int digi_read_oob_callback(struct urb *urb);
250 
251 
252 static const struct usb_device_id id_table_combined[] = {
253 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
254 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
255 	{ }						/* Terminating entry */
256 };
257 
258 static const struct usb_device_id id_table_2[] = {
259 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
260 	{ }						/* Terminating entry */
261 };
262 
263 static const struct usb_device_id id_table_4[] = {
264 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
265 	{ }						/* Terminating entry */
266 };
267 
268 MODULE_DEVICE_TABLE(usb, id_table_combined);
269 
270 /* device info needed for the Digi serial converter */
271 
272 static struct usb_serial_driver digi_acceleport_2_device = {
273 	.driver = {
274 		.owner =		THIS_MODULE,
275 		.name =			"digi_2",
276 	},
277 	.description =			"Digi 2 port USB adapter",
278 	.id_table =			id_table_2,
279 	.num_ports =			3,
280 	.open =				digi_open,
281 	.close =			digi_close,
282 	.dtr_rts =			digi_dtr_rts,
283 	.write =			digi_write,
284 	.write_room =			digi_write_room,
285 	.write_bulk_callback = 		digi_write_bulk_callback,
286 	.read_bulk_callback =		digi_read_bulk_callback,
287 	.chars_in_buffer =		digi_chars_in_buffer,
288 	.throttle =			digi_rx_throttle,
289 	.unthrottle =			digi_rx_unthrottle,
290 	.set_termios =			digi_set_termios,
291 	.break_ctl =			digi_break_ctl,
292 	.tiocmget =			digi_tiocmget,
293 	.tiocmset =			digi_tiocmset,
294 	.attach =			digi_startup,
295 	.disconnect =			digi_disconnect,
296 	.release =			digi_release,
297 };
298 
299 static struct usb_serial_driver digi_acceleport_4_device = {
300 	.driver = {
301 		.owner =		THIS_MODULE,
302 		.name =			"digi_4",
303 	},
304 	.description =			"Digi 4 port USB adapter",
305 	.id_table =			id_table_4,
306 	.num_ports =			4,
307 	.open =				digi_open,
308 	.close =			digi_close,
309 	.write =			digi_write,
310 	.write_room =			digi_write_room,
311 	.write_bulk_callback = 		digi_write_bulk_callback,
312 	.read_bulk_callback =		digi_read_bulk_callback,
313 	.chars_in_buffer =		digi_chars_in_buffer,
314 	.throttle =			digi_rx_throttle,
315 	.unthrottle =			digi_rx_unthrottle,
316 	.set_termios =			digi_set_termios,
317 	.break_ctl =			digi_break_ctl,
318 	.tiocmget =			digi_tiocmget,
319 	.tiocmset =			digi_tiocmset,
320 	.attach =			digi_startup,
321 	.disconnect =			digi_disconnect,
322 	.release =			digi_release,
323 };
324 
325 static struct usb_serial_driver * const serial_drivers[] = {
326 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
327 };
328 
329 /* Functions */
330 
331 /*
332  *  Cond Wait Interruptible Timeout Irqrestore
333  *
334  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
335  *  so that wake ups are not lost if they occur between the unlock
336  *  and the sleep.  In other words, spin_unlock_irqrestore and
337  *  interruptible_sleep_on_timeout are "atomic" with respect to
338  *  wake ups.  This is used to implement condition variables.
339  *
340  *  interruptible_sleep_on_timeout is deprecated and has been replaced
341  *  with the equivalent code.
342  */
343 
344 static long cond_wait_interruptible_timeout_irqrestore(
345 	wait_queue_head_t *q, long timeout,
346 	spinlock_t *lock, unsigned long flags)
347 __releases(lock)
348 {
349 	DEFINE_WAIT(wait);
350 
351 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
352 	spin_unlock_irqrestore(lock, flags);
353 	timeout = schedule_timeout(timeout);
354 	finish_wait(q, &wait);
355 
356 	return timeout;
357 }
358 
359 
360 /*
361  *  Digi Wakeup Write
362  *
363  *  Wake up port, line discipline, and tty processes sleeping
364  *  on writes.
365  */
366 
367 static void digi_wakeup_write_lock(struct work_struct *work)
368 {
369 	struct digi_port *priv =
370 			container_of(work, struct digi_port, dp_wakeup_work);
371 	struct usb_serial_port *port = priv->dp_port;
372 	unsigned long flags;
373 
374 	spin_lock_irqsave(&priv->dp_port_lock, flags);
375 	digi_wakeup_write(port);
376 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
377 }
378 
379 static void digi_wakeup_write(struct usb_serial_port *port)
380 {
381 	struct tty_struct *tty = tty_port_tty_get(&port->port);
382 	if (tty) {
383 		tty_wakeup(tty);
384 		tty_kref_put(tty);
385 	}
386 }
387 
388 
389 /*
390  *  Digi Write OOB Command
391  *
392  *  Write commands on the out of band port.  Commands are 4
393  *  bytes each, multiple commands can be sent at once, and
394  *  no command will be split across USB packets.  Returns 0
395  *  if successful, -EINTR if interrupted while sleeping and
396  *  the interruptible flag is true, or a negative error
397  *  returned by usb_submit_urb.
398  */
399 
400 static int digi_write_oob_command(struct usb_serial_port *port,
401 	unsigned char *buf, int count, int interruptible)
402 {
403 	int ret = 0;
404 	int len;
405 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
406 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
407 	unsigned long flags = 0;
408 
409 	dev_dbg(&port->dev,
410 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
411 		oob_priv->dp_port_num, count);
412 
413 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
414 	while (count > 0) {
415 		while (oob_priv->dp_write_urb_in_use) {
416 			cond_wait_interruptible_timeout_irqrestore(
417 				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
418 				&oob_priv->dp_port_lock, flags);
419 			if (interruptible && signal_pending(current))
420 				return -EINTR;
421 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
422 		}
423 
424 		/* len must be a multiple of 4, so commands are not split */
425 		len = min(count, oob_port->bulk_out_size);
426 		if (len > 4)
427 			len &= ~3;
428 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
429 		oob_port->write_urb->transfer_buffer_length = len;
430 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
431 		if (ret == 0) {
432 			oob_priv->dp_write_urb_in_use = 1;
433 			count -= len;
434 			buf += len;
435 		}
436 	}
437 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
438 	if (ret)
439 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
440 			__func__, ret);
441 	return ret;
442 
443 }
444 
445 
446 /*
447  *  Digi Write In Band Command
448  *
449  *  Write commands on the given port.  Commands are 4
450  *  bytes each, multiple commands can be sent at once, and
451  *  no command will be split across USB packets.  If timeout
452  *  is non-zero, write in band command will return after
453  *  waiting unsuccessfully for the URB status to clear for
454  *  timeout ticks.  Returns 0 if successful, or a negative
455  *  error returned by digi_write.
456  */
457 
458 static int digi_write_inb_command(struct usb_serial_port *port,
459 	unsigned char *buf, int count, unsigned long timeout)
460 {
461 	int ret = 0;
462 	int len;
463 	struct digi_port *priv = usb_get_serial_port_data(port);
464 	unsigned char *data = port->write_urb->transfer_buffer;
465 	unsigned long flags = 0;
466 
467 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
468 		priv->dp_port_num, count);
469 
470 	if (timeout)
471 		timeout += jiffies;
472 	else
473 		timeout = ULONG_MAX;
474 
475 	spin_lock_irqsave(&priv->dp_port_lock, flags);
476 	while (count > 0 && ret == 0) {
477 		while (priv->dp_write_urb_in_use &&
478 		       time_before(jiffies, timeout)) {
479 			cond_wait_interruptible_timeout_irqrestore(
480 				&port->write_wait, DIGI_RETRY_TIMEOUT,
481 				&priv->dp_port_lock, flags);
482 			if (signal_pending(current))
483 				return -EINTR;
484 			spin_lock_irqsave(&priv->dp_port_lock, flags);
485 		}
486 
487 		/* len must be a multiple of 4 and small enough to */
488 		/* guarantee the write will send buffered data first, */
489 		/* so commands are in order with data and not split */
490 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
491 		if (len > 4)
492 			len &= ~3;
493 
494 		/* write any buffered data first */
495 		if (priv->dp_out_buf_len > 0) {
496 			data[0] = DIGI_CMD_SEND_DATA;
497 			data[1] = priv->dp_out_buf_len;
498 			memcpy(data + 2, priv->dp_out_buf,
499 				priv->dp_out_buf_len);
500 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
501 			port->write_urb->transfer_buffer_length
502 				= priv->dp_out_buf_len + 2 + len;
503 		} else {
504 			memcpy(data, buf, len);
505 			port->write_urb->transfer_buffer_length = len;
506 		}
507 
508 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
509 		if (ret == 0) {
510 			priv->dp_write_urb_in_use = 1;
511 			priv->dp_out_buf_len = 0;
512 			count -= len;
513 			buf += len;
514 		}
515 
516 	}
517 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
518 
519 	if (ret)
520 		dev_err(&port->dev,
521 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
522 			__func__, ret, priv->dp_port_num);
523 	return ret;
524 }
525 
526 
527 /*
528  *  Digi Set Modem Signals
529  *
530  *  Sets or clears DTR and RTS on the port, according to the
531  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
532  *  for the modem_signals argument.  Returns 0 if successful,
533  *  -EINTR if interrupted while sleeping, or a non-zero error
534  *  returned by usb_submit_urb.
535  */
536 
537 static int digi_set_modem_signals(struct usb_serial_port *port,
538 	unsigned int modem_signals, int interruptible)
539 {
540 
541 	int ret;
542 	struct digi_port *port_priv = usb_get_serial_port_data(port);
543 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
544 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
545 	unsigned char *data = oob_port->write_urb->transfer_buffer;
546 	unsigned long flags = 0;
547 
548 
549 	dev_dbg(&port->dev,
550 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
551 		port_priv->dp_port_num, modem_signals);
552 
553 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
554 	spin_lock(&port_priv->dp_port_lock);
555 
556 	while (oob_priv->dp_write_urb_in_use) {
557 		spin_unlock(&port_priv->dp_port_lock);
558 		cond_wait_interruptible_timeout_irqrestore(
559 			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
560 			&oob_priv->dp_port_lock, flags);
561 		if (interruptible && signal_pending(current))
562 			return -EINTR;
563 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
564 		spin_lock(&port_priv->dp_port_lock);
565 	}
566 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
567 	data[1] = port_priv->dp_port_num;
568 	data[2] = (modem_signals & TIOCM_DTR) ?
569 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
570 	data[3] = 0;
571 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
572 	data[5] = port_priv->dp_port_num;
573 	data[6] = (modem_signals & TIOCM_RTS) ?
574 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
575 	data[7] = 0;
576 
577 	oob_port->write_urb->transfer_buffer_length = 8;
578 
579 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
580 	if (ret == 0) {
581 		oob_priv->dp_write_urb_in_use = 1;
582 		port_priv->dp_modem_signals =
583 			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
584 			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
585 	}
586 	spin_unlock(&port_priv->dp_port_lock);
587 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
588 	if (ret)
589 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
590 			__func__, ret);
591 	return ret;
592 }
593 
594 /*
595  *  Digi Transmit Idle
596  *
597  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
598  *  to go idle.  It returns 0 if successful or a negative error.
599  *
600  *  There are race conditions here if more than one process is calling
601  *  digi_transmit_idle on the same port at the same time.  However, this
602  *  is only called from close, and only one process can be in close on a
603  *  port at a time, so its ok.
604  */
605 
606 static int digi_transmit_idle(struct usb_serial_port *port,
607 	unsigned long timeout)
608 {
609 	int ret;
610 	unsigned char buf[2];
611 	struct digi_port *priv = usb_get_serial_port_data(port);
612 	unsigned long flags = 0;
613 
614 	spin_lock_irqsave(&priv->dp_port_lock, flags);
615 	priv->dp_transmit_idle = 0;
616 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
617 
618 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
619 	buf[1] = 0;
620 
621 	timeout += jiffies;
622 
623 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
624 	if (ret != 0)
625 		return ret;
626 
627 	spin_lock_irqsave(&priv->dp_port_lock, flags);
628 
629 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
630 		cond_wait_interruptible_timeout_irqrestore(
631 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
632 			&priv->dp_port_lock, flags);
633 		if (signal_pending(current))
634 			return -EINTR;
635 		spin_lock_irqsave(&priv->dp_port_lock, flags);
636 	}
637 	priv->dp_transmit_idle = 0;
638 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
639 	return 0;
640 
641 }
642 
643 
644 static void digi_rx_throttle(struct tty_struct *tty)
645 {
646 	unsigned long flags;
647 	struct usb_serial_port *port = tty->driver_data;
648 	struct digi_port *priv = usb_get_serial_port_data(port);
649 
650 	/* stop receiving characters by not resubmitting the read urb */
651 	spin_lock_irqsave(&priv->dp_port_lock, flags);
652 	priv->dp_throttled = 1;
653 	priv->dp_throttle_restart = 0;
654 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
655 }
656 
657 
658 static void digi_rx_unthrottle(struct tty_struct *tty)
659 {
660 	int ret = 0;
661 	unsigned long flags;
662 	struct usb_serial_port *port = tty->driver_data;
663 	struct digi_port *priv = usb_get_serial_port_data(port);
664 
665 	spin_lock_irqsave(&priv->dp_port_lock, flags);
666 
667 	/* restart read chain */
668 	if (priv->dp_throttle_restart)
669 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
670 
671 	/* turn throttle off */
672 	priv->dp_throttled = 0;
673 	priv->dp_throttle_restart = 0;
674 
675 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
676 
677 	if (ret)
678 		dev_err(&port->dev,
679 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
680 			__func__, ret, priv->dp_port_num);
681 }
682 
683 
684 static void digi_set_termios(struct tty_struct *tty,
685 		struct usb_serial_port *port, struct ktermios *old_termios)
686 {
687 	struct digi_port *priv = usb_get_serial_port_data(port);
688 	struct device *dev = &port->dev;
689 	unsigned int iflag = tty->termios.c_iflag;
690 	unsigned int cflag = tty->termios.c_cflag;
691 	unsigned int old_iflag = old_termios->c_iflag;
692 	unsigned int old_cflag = old_termios->c_cflag;
693 	unsigned char buf[32];
694 	unsigned int modem_signals;
695 	int arg, ret;
696 	int i = 0;
697 	speed_t baud;
698 
699 	dev_dbg(dev,
700 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
701 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
702 
703 	/* set baud rate */
704 	baud = tty_get_baud_rate(tty);
705 	if (baud != tty_termios_baud_rate(old_termios)) {
706 		arg = -1;
707 
708 		/* reassert DTR and (maybe) RTS on transition from B0 */
709 		if ((old_cflag&CBAUD) == B0) {
710 			/* don't set RTS if using hardware flow control */
711 			/* and throttling input */
712 			modem_signals = TIOCM_DTR;
713 			if (!(tty->termios.c_cflag & CRTSCTS) ||
714 			    !test_bit(TTY_THROTTLED, &tty->flags))
715 				modem_signals |= TIOCM_RTS;
716 			digi_set_modem_signals(port, modem_signals, 1);
717 		}
718 		switch (baud) {
719 		/* drop DTR and RTS on transition to B0 */
720 		case 0: digi_set_modem_signals(port, 0, 1); break;
721 		case 50: arg = DIGI_BAUD_50; break;
722 		case 75: arg = DIGI_BAUD_75; break;
723 		case 110: arg = DIGI_BAUD_110; break;
724 		case 150: arg = DIGI_BAUD_150; break;
725 		case 200: arg = DIGI_BAUD_200; break;
726 		case 300: arg = DIGI_BAUD_300; break;
727 		case 600: arg = DIGI_BAUD_600; break;
728 		case 1200: arg = DIGI_BAUD_1200; break;
729 		case 1800: arg = DIGI_BAUD_1800; break;
730 		case 2400: arg = DIGI_BAUD_2400; break;
731 		case 4800: arg = DIGI_BAUD_4800; break;
732 		case 9600: arg = DIGI_BAUD_9600; break;
733 		case 19200: arg = DIGI_BAUD_19200; break;
734 		case 38400: arg = DIGI_BAUD_38400; break;
735 		case 57600: arg = DIGI_BAUD_57600; break;
736 		case 115200: arg = DIGI_BAUD_115200; break;
737 		case 230400: arg = DIGI_BAUD_230400; break;
738 		case 460800: arg = DIGI_BAUD_460800; break;
739 		default:
740 			arg = DIGI_BAUD_9600;
741 			baud = 9600;
742 			break;
743 		}
744 		if (arg != -1) {
745 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
746 			buf[i++] = priv->dp_port_num;
747 			buf[i++] = arg;
748 			buf[i++] = 0;
749 		}
750 	}
751 	/* set parity */
752 	tty->termios.c_cflag &= ~CMSPAR;
753 
754 	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
755 		if (cflag&PARENB) {
756 			if (cflag&PARODD)
757 				arg = DIGI_PARITY_ODD;
758 			else
759 				arg = DIGI_PARITY_EVEN;
760 		} else {
761 			arg = DIGI_PARITY_NONE;
762 		}
763 		buf[i++] = DIGI_CMD_SET_PARITY;
764 		buf[i++] = priv->dp_port_num;
765 		buf[i++] = arg;
766 		buf[i++] = 0;
767 	}
768 	/* set word size */
769 	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
770 		arg = -1;
771 		switch (cflag&CSIZE) {
772 		case CS5: arg = DIGI_WORD_SIZE_5; break;
773 		case CS6: arg = DIGI_WORD_SIZE_6; break;
774 		case CS7: arg = DIGI_WORD_SIZE_7; break;
775 		case CS8: arg = DIGI_WORD_SIZE_8; break;
776 		default:
777 			dev_dbg(dev,
778 				"digi_set_termios: can't handle word size %d\n",
779 				(cflag&CSIZE));
780 			break;
781 		}
782 
783 		if (arg != -1) {
784 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
785 			buf[i++] = priv->dp_port_num;
786 			buf[i++] = arg;
787 			buf[i++] = 0;
788 		}
789 
790 	}
791 
792 	/* set stop bits */
793 	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
794 
795 		if ((cflag&CSTOPB))
796 			arg = DIGI_STOP_BITS_2;
797 		else
798 			arg = DIGI_STOP_BITS_1;
799 
800 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
801 		buf[i++] = priv->dp_port_num;
802 		buf[i++] = arg;
803 		buf[i++] = 0;
804 
805 	}
806 
807 	/* set input flow control */
808 	if ((iflag&IXOFF) != (old_iflag&IXOFF)
809 	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
810 		arg = 0;
811 		if (iflag&IXOFF)
812 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
813 		else
814 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
815 
816 		if (cflag&CRTSCTS) {
817 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
818 
819 			/* On USB-4 it is necessary to assert RTS prior */
820 			/* to selecting RTS input flow control.  */
821 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
822 			buf[i++] = priv->dp_port_num;
823 			buf[i++] = DIGI_RTS_ACTIVE;
824 			buf[i++] = 0;
825 
826 		} else {
827 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
828 		}
829 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
830 		buf[i++] = priv->dp_port_num;
831 		buf[i++] = arg;
832 		buf[i++] = 0;
833 	}
834 
835 	/* set output flow control */
836 	if ((iflag & IXON) != (old_iflag & IXON)
837 	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
838 		arg = 0;
839 		if (iflag & IXON)
840 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
841 		else
842 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
843 
844 		if (cflag & CRTSCTS) {
845 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
846 		} else {
847 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
848 			tty->hw_stopped = 0;
849 		}
850 
851 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
852 		buf[i++] = priv->dp_port_num;
853 		buf[i++] = arg;
854 		buf[i++] = 0;
855 	}
856 
857 	/* set receive enable/disable */
858 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
859 		if (cflag & CREAD)
860 			arg = DIGI_ENABLE;
861 		else
862 			arg = DIGI_DISABLE;
863 
864 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
865 		buf[i++] = priv->dp_port_num;
866 		buf[i++] = arg;
867 		buf[i++] = 0;
868 	}
869 	ret = digi_write_oob_command(port, buf, i, 1);
870 	if (ret != 0)
871 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
872 	tty_encode_baud_rate(tty, baud, baud);
873 }
874 
875 
876 static void digi_break_ctl(struct tty_struct *tty, int break_state)
877 {
878 	struct usb_serial_port *port = tty->driver_data;
879 	unsigned char buf[4];
880 
881 	buf[0] = DIGI_CMD_BREAK_CONTROL;
882 	buf[1] = 2;				/* length */
883 	buf[2] = break_state ? 1 : 0;
884 	buf[3] = 0;				/* pad */
885 	digi_write_inb_command(port, buf, 4, 0);
886 }
887 
888 
889 static int digi_tiocmget(struct tty_struct *tty)
890 {
891 	struct usb_serial_port *port = tty->driver_data;
892 	struct digi_port *priv = usb_get_serial_port_data(port);
893 	unsigned int val;
894 	unsigned long flags;
895 
896 	spin_lock_irqsave(&priv->dp_port_lock, flags);
897 	val = priv->dp_modem_signals;
898 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
899 	return val;
900 }
901 
902 
903 static int digi_tiocmset(struct tty_struct *tty,
904 					unsigned int set, unsigned int clear)
905 {
906 	struct usb_serial_port *port = tty->driver_data;
907 	struct digi_port *priv = usb_get_serial_port_data(port);
908 	unsigned int val;
909 	unsigned long flags;
910 
911 	spin_lock_irqsave(&priv->dp_port_lock, flags);
912 	val = (priv->dp_modem_signals & ~clear) | set;
913 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
914 	return digi_set_modem_signals(port, val, 1);
915 }
916 
917 
918 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
919 					const unsigned char *buf, int count)
920 {
921 
922 	int ret, data_len, new_len;
923 	struct digi_port *priv = usb_get_serial_port_data(port);
924 	unsigned char *data = port->write_urb->transfer_buffer;
925 	unsigned long flags = 0;
926 
927 	dev_dbg(&port->dev,
928 		"digi_write: TOP: port=%d, count=%d, in_interrupt=%ld\n",
929 		priv->dp_port_num, count, in_interrupt());
930 
931 	/* copy user data (which can sleep) before getting spin lock */
932 	count = min(count, port->bulk_out_size-2);
933 	count = min(64, count);
934 
935 	/* be sure only one write proceeds at a time */
936 	/* there are races on the port private buffer */
937 	spin_lock_irqsave(&priv->dp_port_lock, flags);
938 
939 	/* wait for urb status clear to submit another urb */
940 	if (priv->dp_write_urb_in_use) {
941 		/* buffer data if count is 1 (probably put_char) if possible */
942 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
943 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
944 			new_len = 1;
945 		} else {
946 			new_len = 0;
947 		}
948 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
949 		return new_len;
950 	}
951 
952 	/* allow space for any buffered data and for new data, up to */
953 	/* transfer buffer size - 2 (for command and length bytes) */
954 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
955 	data_len = new_len + priv->dp_out_buf_len;
956 
957 	if (data_len == 0) {
958 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
959 		return 0;
960 	}
961 
962 	port->write_urb->transfer_buffer_length = data_len+2;
963 
964 	*data++ = DIGI_CMD_SEND_DATA;
965 	*data++ = data_len;
966 
967 	/* copy in buffered data first */
968 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
969 	data += priv->dp_out_buf_len;
970 
971 	/* copy in new data */
972 	memcpy(data, buf, new_len);
973 
974 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
975 	if (ret == 0) {
976 		priv->dp_write_urb_in_use = 1;
977 		ret = new_len;
978 		priv->dp_out_buf_len = 0;
979 	}
980 
981 	/* return length of new data written, or error */
982 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
983 	if (ret < 0)
984 		dev_err_console(port,
985 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
986 			__func__, ret, priv->dp_port_num);
987 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
988 	return ret;
989 
990 }
991 
992 static void digi_write_bulk_callback(struct urb *urb)
993 {
994 
995 	struct usb_serial_port *port = urb->context;
996 	struct usb_serial *serial;
997 	struct digi_port *priv;
998 	struct digi_serial *serial_priv;
999 	int ret = 0;
1000 	int status = urb->status;
1001 
1002 	/* port and serial sanity check */
1003 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
1004 		pr_err("%s: port or port->private is NULL, status=%d\n",
1005 			__func__, status);
1006 		return;
1007 	}
1008 	serial = port->serial;
1009 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
1010 		dev_err(&port->dev,
1011 			"%s: serial or serial->private is NULL, status=%d\n",
1012 			__func__, status);
1013 		return;
1014 	}
1015 
1016 	/* handle oob callback */
1017 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1018 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
1019 		spin_lock(&priv->dp_port_lock);
1020 		priv->dp_write_urb_in_use = 0;
1021 		wake_up_interruptible(&port->write_wait);
1022 		spin_unlock(&priv->dp_port_lock);
1023 		return;
1024 	}
1025 
1026 	/* try to send any buffered data on this port */
1027 	spin_lock(&priv->dp_port_lock);
1028 	priv->dp_write_urb_in_use = 0;
1029 	if (priv->dp_out_buf_len > 0) {
1030 		*((unsigned char *)(port->write_urb->transfer_buffer))
1031 			= (unsigned char)DIGI_CMD_SEND_DATA;
1032 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1033 			= (unsigned char)priv->dp_out_buf_len;
1034 		port->write_urb->transfer_buffer_length =
1035 						priv->dp_out_buf_len + 2;
1036 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1037 			priv->dp_out_buf_len);
1038 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1039 		if (ret == 0) {
1040 			priv->dp_write_urb_in_use = 1;
1041 			priv->dp_out_buf_len = 0;
1042 		}
1043 	}
1044 	/* wake up processes sleeping on writes immediately */
1045 	digi_wakeup_write(port);
1046 	/* also queue up a wakeup at scheduler time, in case we */
1047 	/* lost the race in write_chan(). */
1048 	schedule_work(&priv->dp_wakeup_work);
1049 
1050 	spin_unlock(&priv->dp_port_lock);
1051 	if (ret && ret != -EPERM)
1052 		dev_err_console(port,
1053 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1054 			__func__, ret, priv->dp_port_num);
1055 }
1056 
1057 static int digi_write_room(struct tty_struct *tty)
1058 {
1059 	struct usb_serial_port *port = tty->driver_data;
1060 	struct digi_port *priv = usb_get_serial_port_data(port);
1061 	int room;
1062 	unsigned long flags = 0;
1063 
1064 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1065 
1066 	if (priv->dp_write_urb_in_use)
1067 		room = 0;
1068 	else
1069 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1070 
1071 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1072 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%d\n", priv->dp_port_num, room);
1073 	return room;
1074 
1075 }
1076 
1077 static int digi_chars_in_buffer(struct tty_struct *tty)
1078 {
1079 	struct usb_serial_port *port = tty->driver_data;
1080 	struct digi_port *priv = usb_get_serial_port_data(port);
1081 
1082 	if (priv->dp_write_urb_in_use) {
1083 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1084 			priv->dp_port_num, port->bulk_out_size - 2);
1085 		/* return(port->bulk_out_size - 2); */
1086 		return 256;
1087 	} else {
1088 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1089 			priv->dp_port_num, priv->dp_out_buf_len);
1090 		return priv->dp_out_buf_len;
1091 	}
1092 
1093 }
1094 
1095 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1096 {
1097 	/* Adjust DTR and RTS */
1098 	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
1099 }
1100 
1101 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1102 {
1103 	int ret;
1104 	unsigned char buf[32];
1105 	struct digi_port *priv = usb_get_serial_port_data(port);
1106 	struct ktermios not_termios;
1107 
1108 	/* be sure the device is started up */
1109 	if (digi_startup_device(port->serial) != 0)
1110 		return -ENXIO;
1111 
1112 	/* read modem signals automatically whenever they change */
1113 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1114 	buf[1] = priv->dp_port_num;
1115 	buf[2] = DIGI_ENABLE;
1116 	buf[3] = 0;
1117 
1118 	/* flush fifos */
1119 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1120 	buf[5] = priv->dp_port_num;
1121 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1122 	buf[7] = 0;
1123 
1124 	ret = digi_write_oob_command(port, buf, 8, 1);
1125 	if (ret != 0)
1126 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1127 
1128 	/* set termios settings */
1129 	if (tty) {
1130 		not_termios.c_cflag = ~tty->termios.c_cflag;
1131 		not_termios.c_iflag = ~tty->termios.c_iflag;
1132 		digi_set_termios(tty, port, &not_termios);
1133 	}
1134 	return 0;
1135 }
1136 
1137 
1138 static void digi_close(struct usb_serial_port *port)
1139 {
1140 	DEFINE_WAIT(wait);
1141 	int ret;
1142 	unsigned char buf[32];
1143 	struct digi_port *priv = usb_get_serial_port_data(port);
1144 
1145 	mutex_lock(&port->serial->disc_mutex);
1146 	/* if disconnected, just clear flags */
1147 	if (port->serial->disconnected)
1148 		goto exit;
1149 
1150 	if (port->serial->dev) {
1151 		/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1152 		digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1153 
1154 		/* disable input flow control */
1155 		buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1156 		buf[1] = priv->dp_port_num;
1157 		buf[2] = DIGI_DISABLE;
1158 		buf[3] = 0;
1159 
1160 		/* disable output flow control */
1161 		buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1162 		buf[5] = priv->dp_port_num;
1163 		buf[6] = DIGI_DISABLE;
1164 		buf[7] = 0;
1165 
1166 		/* disable reading modem signals automatically */
1167 		buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1168 		buf[9] = priv->dp_port_num;
1169 		buf[10] = DIGI_DISABLE;
1170 		buf[11] = 0;
1171 
1172 		/* disable receive */
1173 		buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1174 		buf[13] = priv->dp_port_num;
1175 		buf[14] = DIGI_DISABLE;
1176 		buf[15] = 0;
1177 
1178 		/* flush fifos */
1179 		buf[16] = DIGI_CMD_IFLUSH_FIFO;
1180 		buf[17] = priv->dp_port_num;
1181 		buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1182 		buf[19] = 0;
1183 
1184 		ret = digi_write_oob_command(port, buf, 20, 0);
1185 		if (ret != 0)
1186 			dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n", ret);
1187 
1188 		/* wait for final commands on oob port to complete */
1189 		prepare_to_wait(&priv->dp_flush_wait, &wait,
1190 							TASK_INTERRUPTIBLE);
1191 		schedule_timeout(DIGI_CLOSE_TIMEOUT);
1192 		finish_wait(&priv->dp_flush_wait, &wait);
1193 
1194 		/* shutdown any outstanding bulk writes */
1195 		usb_kill_urb(port->write_urb);
1196 	}
1197 exit:
1198 	spin_lock_irq(&priv->dp_port_lock);
1199 	priv->dp_write_urb_in_use = 0;
1200 	wake_up_interruptible(&priv->dp_close_wait);
1201 	spin_unlock_irq(&priv->dp_port_lock);
1202 	mutex_unlock(&port->serial->disc_mutex);
1203 }
1204 
1205 
1206 /*
1207  *  Digi Startup Device
1208  *
1209  *  Starts reads on all ports.  Must be called AFTER startup, with
1210  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1211  */
1212 
1213 static int digi_startup_device(struct usb_serial *serial)
1214 {
1215 	int i, ret = 0;
1216 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1217 	struct usb_serial_port *port;
1218 
1219 	/* be sure this happens exactly once */
1220 	spin_lock(&serial_priv->ds_serial_lock);
1221 	if (serial_priv->ds_device_started) {
1222 		spin_unlock(&serial_priv->ds_serial_lock);
1223 		return 0;
1224 	}
1225 	serial_priv->ds_device_started = 1;
1226 	spin_unlock(&serial_priv->ds_serial_lock);
1227 
1228 	/* start reading from each bulk in endpoint for the device */
1229 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1230 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1231 		port = serial->port[i];
1232 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1233 		if (ret != 0) {
1234 			dev_err(&port->dev,
1235 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1236 				__func__, ret, i);
1237 			break;
1238 		}
1239 	}
1240 	return ret;
1241 }
1242 
1243 
1244 static int digi_startup(struct usb_serial *serial)
1245 {
1246 
1247 	int i;
1248 	struct digi_port *priv;
1249 	struct digi_serial *serial_priv;
1250 
1251 	/* allocate the private data structures for all ports */
1252 	/* number of regular ports + 1 for the out-of-band port */
1253 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1254 		/* allocate port private structure */
1255 		priv = kmalloc(sizeof(struct digi_port), GFP_KERNEL);
1256 		if (priv == NULL) {
1257 			while (--i >= 0)
1258 				kfree(usb_get_serial_port_data(serial->port[i]));
1259 			return 1;			/* error */
1260 		}
1261 
1262 		/* initialize port private structure */
1263 		spin_lock_init(&priv->dp_port_lock);
1264 		priv->dp_port_num = i;
1265 		priv->dp_out_buf_len = 0;
1266 		priv->dp_write_urb_in_use = 0;
1267 		priv->dp_modem_signals = 0;
1268 		init_waitqueue_head(&priv->dp_modem_change_wait);
1269 		priv->dp_transmit_idle = 0;
1270 		init_waitqueue_head(&priv->dp_transmit_idle_wait);
1271 		priv->dp_throttled = 0;
1272 		priv->dp_throttle_restart = 0;
1273 		init_waitqueue_head(&priv->dp_flush_wait);
1274 		init_waitqueue_head(&priv->dp_close_wait);
1275 		INIT_WORK(&priv->dp_wakeup_work, digi_wakeup_write_lock);
1276 		priv->dp_port = serial->port[i];
1277 		/* initialize write wait queue for this port */
1278 		init_waitqueue_head(&serial->port[i]->write_wait);
1279 
1280 		usb_set_serial_port_data(serial->port[i], priv);
1281 	}
1282 
1283 	/* allocate serial private structure */
1284 	serial_priv = kmalloc(sizeof(struct digi_serial), GFP_KERNEL);
1285 	if (serial_priv == NULL) {
1286 		for (i = 0; i < serial->type->num_ports + 1; i++)
1287 			kfree(usb_get_serial_port_data(serial->port[i]));
1288 		return 1;			/* error */
1289 	}
1290 
1291 	/* initialize serial private structure */
1292 	spin_lock_init(&serial_priv->ds_serial_lock);
1293 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1294 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1295 	serial_priv->ds_device_started = 0;
1296 	usb_set_serial_data(serial, serial_priv);
1297 
1298 	return 0;
1299 }
1300 
1301 
1302 static void digi_disconnect(struct usb_serial *serial)
1303 {
1304 	int i;
1305 
1306 	/* stop reads and writes on all ports */
1307 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1308 		usb_kill_urb(serial->port[i]->read_urb);
1309 		usb_kill_urb(serial->port[i]->write_urb);
1310 	}
1311 }
1312 
1313 
1314 static void digi_release(struct usb_serial *serial)
1315 {
1316 	int i;
1317 
1318 	/* free the private data structures for all ports */
1319 	/* number of regular ports + 1 for the out-of-band port */
1320 	for (i = 0; i < serial->type->num_ports + 1; i++)
1321 		kfree(usb_get_serial_port_data(serial->port[i]));
1322 	kfree(usb_get_serial_data(serial));
1323 }
1324 
1325 
1326 static void digi_read_bulk_callback(struct urb *urb)
1327 {
1328 	struct usb_serial_port *port = urb->context;
1329 	struct digi_port *priv;
1330 	struct digi_serial *serial_priv;
1331 	int ret;
1332 	int status = urb->status;
1333 
1334 	/* port sanity check, do not resubmit if port is not valid */
1335 	if (port == NULL)
1336 		return;
1337 	priv = usb_get_serial_port_data(port);
1338 	if (priv == NULL) {
1339 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1340 			__func__, status);
1341 		return;
1342 	}
1343 	if (port->serial == NULL ||
1344 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1345 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1346 			"is NULL, status=%d\n", __func__, status);
1347 		return;
1348 	}
1349 
1350 	/* do not resubmit urb if it has any status error */
1351 	if (status) {
1352 		dev_err(&port->dev,
1353 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1354 			__func__, status, priv->dp_port_num);
1355 		return;
1356 	}
1357 
1358 	/* handle oob or inb callback, do not resubmit if error */
1359 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1360 		if (digi_read_oob_callback(urb) != 0)
1361 			return;
1362 	} else {
1363 		if (digi_read_inb_callback(urb) != 0)
1364 			return;
1365 	}
1366 
1367 	/* continue read */
1368 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1369 	if (ret != 0 && ret != -EPERM) {
1370 		dev_err(&port->dev,
1371 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1372 			__func__, ret, priv->dp_port_num);
1373 	}
1374 
1375 }
1376 
1377 /*
1378  *  Digi Read INB Callback
1379  *
1380  *  Digi Read INB Callback handles reads on the in band ports, sending
1381  *  the data on to the tty subsystem.  When called we know port and
1382  *  port->private are not NULL and port->serial has been validated.
1383  *  It returns 0 if successful, 1 if successful but the port is
1384  *  throttled, and -1 if the sanity checks failed.
1385  */
1386 
1387 static int digi_read_inb_callback(struct urb *urb)
1388 {
1389 
1390 	struct usb_serial_port *port = urb->context;
1391 	struct tty_struct *tty;
1392 	struct digi_port *priv = usb_get_serial_port_data(port);
1393 	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
1394 	int len = ((unsigned char *)urb->transfer_buffer)[1];
1395 	int port_status = ((unsigned char *)urb->transfer_buffer)[2];
1396 	unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
1397 	int flag, throttled;
1398 	int status = urb->status;
1399 
1400 	/* do not process callbacks on closed ports */
1401 	/* but do continue the read chain */
1402 	if (urb->status == -ENOENT)
1403 		return 0;
1404 
1405 	/* short/multiple packet check */
1406 	if (urb->actual_length != len + 2) {
1407 		dev_err(&port->dev, "%s: INCOMPLETE OR MULTIPLE PACKET, "
1408 			"status=%d, port=%d, opcode=%d, len=%d, "
1409 			"actual_length=%d, status=%d\n", __func__, status,
1410 			priv->dp_port_num, opcode, len, urb->actual_length,
1411 			port_status);
1412 		return -1;
1413 	}
1414 
1415 	tty = tty_port_tty_get(&port->port);
1416 	spin_lock(&priv->dp_port_lock);
1417 
1418 	/* check for throttle; if set, do not resubmit read urb */
1419 	/* indicate the read chain needs to be restarted on unthrottle */
1420 	throttled = priv->dp_throttled;
1421 	if (throttled)
1422 		priv->dp_throttle_restart = 1;
1423 
1424 	/* receive data */
1425 	if (tty && opcode == DIGI_CMD_RECEIVE_DATA) {
1426 		/* get flag from port_status */
1427 		flag = 0;
1428 
1429 		/* overrun is special, not associated with a char */
1430 		if (port_status & DIGI_OVERRUN_ERROR)
1431 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1432 
1433 		/* break takes precedence over parity, */
1434 		/* which takes precedence over framing errors */
1435 		if (port_status & DIGI_BREAK_ERROR)
1436 			flag = TTY_BREAK;
1437 		else if (port_status & DIGI_PARITY_ERROR)
1438 			flag = TTY_PARITY;
1439 		else if (port_status & DIGI_FRAMING_ERROR)
1440 			flag = TTY_FRAME;
1441 
1442 		/* data length is len-1 (one byte of len is port_status) */
1443 		--len;
1444 		if (len > 0) {
1445 			tty_insert_flip_string_fixed_flag(tty, data, flag,
1446 									len);
1447 			tty_flip_buffer_push(tty);
1448 		}
1449 	}
1450 	spin_unlock(&priv->dp_port_lock);
1451 	tty_kref_put(tty);
1452 
1453 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1454 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1455 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1456 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1457 
1458 	return throttled ? 1 : 0;
1459 
1460 }
1461 
1462 
1463 /*
1464  *  Digi Read OOB Callback
1465  *
1466  *  Digi Read OOB Callback handles reads on the out of band port.
1467  *  When called we know port and port->private are not NULL and
1468  *  the port->serial is valid.  It returns 0 if successful, and
1469  *  -1 if the sanity checks failed.
1470  */
1471 
1472 static int digi_read_oob_callback(struct urb *urb)
1473 {
1474 
1475 	struct usb_serial_port *port = urb->context;
1476 	struct usb_serial *serial = port->serial;
1477 	struct tty_struct *tty;
1478 	struct digi_port *priv = usb_get_serial_port_data(port);
1479 	int opcode, line, status, val;
1480 	int i;
1481 	unsigned int rts;
1482 
1483 	/* handle each oob command */
1484 	for (i = 0; i < urb->actual_length - 3;) {
1485 		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
1486 		line = ((unsigned char *)urb->transfer_buffer)[i++];
1487 		status = ((unsigned char *)urb->transfer_buffer)[i++];
1488 		val = ((unsigned char *)urb->transfer_buffer)[i++];
1489 
1490 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1491 			opcode, line, status, val);
1492 
1493 		if (status != 0 || line >= serial->type->num_ports)
1494 			continue;
1495 
1496 		port = serial->port[line];
1497 
1498 		priv = usb_get_serial_port_data(port);
1499 		if (priv == NULL)
1500 			return -1;
1501 
1502 		tty = tty_port_tty_get(&port->port);
1503 
1504 		rts = 0;
1505 		if (tty)
1506 			rts = tty->termios.c_cflag & CRTSCTS;
1507 
1508 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1509 			spin_lock(&priv->dp_port_lock);
1510 			/* convert from digi flags to termiox flags */
1511 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1512 				priv->dp_modem_signals |= TIOCM_CTS;
1513 				/* port must be open to use tty struct */
1514 				if (rts) {
1515 					tty->hw_stopped = 0;
1516 					digi_wakeup_write(port);
1517 				}
1518 			} else {
1519 				priv->dp_modem_signals &= ~TIOCM_CTS;
1520 				/* port must be open to use tty struct */
1521 				if (rts)
1522 					tty->hw_stopped = 1;
1523 			}
1524 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1525 				priv->dp_modem_signals |= TIOCM_DSR;
1526 			else
1527 				priv->dp_modem_signals &= ~TIOCM_DSR;
1528 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1529 				priv->dp_modem_signals |= TIOCM_RI;
1530 			else
1531 				priv->dp_modem_signals &= ~TIOCM_RI;
1532 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1533 				priv->dp_modem_signals |= TIOCM_CD;
1534 			else
1535 				priv->dp_modem_signals &= ~TIOCM_CD;
1536 
1537 			wake_up_interruptible(&priv->dp_modem_change_wait);
1538 			spin_unlock(&priv->dp_port_lock);
1539 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1540 			spin_lock(&priv->dp_port_lock);
1541 			priv->dp_transmit_idle = 1;
1542 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1543 			spin_unlock(&priv->dp_port_lock);
1544 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1545 			wake_up_interruptible(&priv->dp_flush_wait);
1546 		}
1547 		tty_kref_put(tty);
1548 	}
1549 	return 0;
1550 
1551 }
1552 
1553 module_usb_serial_driver(serial_drivers, id_table_combined);
1554 
1555 MODULE_AUTHOR(DRIVER_AUTHOR);
1556 MODULE_DESCRIPTION(DRIVER_DESC);
1557 MODULE_LICENSE("GPL");
1558