xref: /openbmc/linux/drivers/usb/serial/pl2303.c (revision c21b37f6)
1 /*
2  * Prolific PL2303 USB to serial adaptor driver
3  *
4  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
5  * Copyright (C) 2003 IBM Corp.
6  *
7  * Original driver for 2.2.x by anonymous
8  *
9  *	This program is free software; you can redistribute it and/or
10  *	modify it under the terms of the GNU General Public License version
11  *	2 as published by the Free Software Foundation.
12  *
13  * See Documentation/usb/usb-serial.txt for more information on using this driver
14  *
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/tty.h>
22 #include <linux/tty_driver.h>
23 #include <linux/tty_flip.h>
24 #include <linux/serial.h>
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/spinlock.h>
28 #include <asm/uaccess.h>
29 #include <linux/usb.h>
30 #include <linux/usb/serial.h>
31 #include "pl2303.h"
32 
33 /*
34  * Version Information
35  */
36 #define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"
37 
38 static int debug;
39 
40 #define PL2303_CLOSING_WAIT	(30*HZ)
41 
42 #define PL2303_BUF_SIZE		1024
43 #define PL2303_TMP_BUF_SIZE	1024
44 
45 struct pl2303_buf {
46 	unsigned int	buf_size;
47 	char		*buf_buf;
48 	char		*buf_get;
49 	char		*buf_put;
50 };
51 
52 static struct usb_device_id id_table [] = {
53 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
54 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
55 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
56 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
57 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
58 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
59 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
60 	{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
61 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
62 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
63 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
64 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
65 	{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
66 	{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
67 	{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
68 	{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
69 	{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
70 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
71 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
72 	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
73 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
74 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
75 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
76 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
77 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
78 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
79 	{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
80 	{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
81 	{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
82 	{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
83 	{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
84 	{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID) },
85 	{ USB_DEVICE(HUAWEI_VENDOR_ID, HUAWEI_PRODUCT_ID) },
86 	{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
87 	{ }					/* Terminating entry */
88 };
89 
90 MODULE_DEVICE_TABLE(usb, id_table);
91 
92 static struct usb_driver pl2303_driver = {
93 	.name =		"pl2303",
94 	.probe =	usb_serial_probe,
95 	.disconnect =	usb_serial_disconnect,
96 	.id_table =	id_table,
97 	.no_dynamic_id = 	1,
98 };
99 
100 #define SET_LINE_REQUEST_TYPE		0x21
101 #define SET_LINE_REQUEST		0x20
102 
103 #define SET_CONTROL_REQUEST_TYPE	0x21
104 #define SET_CONTROL_REQUEST		0x22
105 #define CONTROL_DTR			0x01
106 #define CONTROL_RTS			0x02
107 
108 #define BREAK_REQUEST_TYPE		0x21
109 #define BREAK_REQUEST			0x23
110 #define BREAK_ON			0xffff
111 #define BREAK_OFF			0x0000
112 
113 #define GET_LINE_REQUEST_TYPE		0xa1
114 #define GET_LINE_REQUEST		0x21
115 
116 #define VENDOR_WRITE_REQUEST_TYPE	0x40
117 #define VENDOR_WRITE_REQUEST		0x01
118 
119 #define VENDOR_READ_REQUEST_TYPE	0xc0
120 #define VENDOR_READ_REQUEST		0x01
121 
122 #define UART_STATE			0x08
123 #define UART_STATE_TRANSIENT_MASK	0x74
124 #define UART_DCD			0x01
125 #define UART_DSR			0x02
126 #define UART_BREAK_ERROR		0x04
127 #define UART_RING			0x08
128 #define UART_FRAME_ERROR		0x10
129 #define UART_PARITY_ERROR		0x20
130 #define UART_OVERRUN_ERROR		0x40
131 #define UART_CTS			0x80
132 
133 
134 enum pl2303_type {
135 	type_0,		/* don't know the difference between type 0 and */
136 	type_1,		/* type 1, until someone from prolific tells us... */
137 	HX,		/* HX version of the pl2303 chip */
138 };
139 
140 struct pl2303_private {
141 	spinlock_t lock;
142 	struct pl2303_buf *buf;
143 	int write_urb_in_use;
144 	wait_queue_head_t delta_msr_wait;
145 	u8 line_control;
146 	u8 line_status;
147 	u8 termios_initialized;
148 	enum pl2303_type type;
149 };
150 
151 /*
152  * pl2303_buf_alloc
153  *
154  * Allocate a circular buffer and all associated memory.
155  */
156 static struct pl2303_buf *pl2303_buf_alloc(unsigned int size)
157 {
158 	struct pl2303_buf *pb;
159 
160 	if (size == 0)
161 		return NULL;
162 
163 	pb = kmalloc(sizeof(struct pl2303_buf), GFP_KERNEL);
164 	if (pb == NULL)
165 		return NULL;
166 
167 	pb->buf_buf = kmalloc(size, GFP_KERNEL);
168 	if (pb->buf_buf == NULL) {
169 		kfree(pb);
170 		return NULL;
171 	}
172 
173 	pb->buf_size = size;
174 	pb->buf_get = pb->buf_put = pb->buf_buf;
175 
176 	return pb;
177 }
178 
179 /*
180  * pl2303_buf_free
181  *
182  * Free the buffer and all associated memory.
183  */
184 static void pl2303_buf_free(struct pl2303_buf *pb)
185 {
186 	if (pb) {
187 		kfree(pb->buf_buf);
188 		kfree(pb);
189 	}
190 }
191 
192 /*
193  * pl2303_buf_clear
194  *
195  * Clear out all data in the circular buffer.
196  */
197 static void pl2303_buf_clear(struct pl2303_buf *pb)
198 {
199 	if (pb != NULL)
200 		pb->buf_get = pb->buf_put;
201 		/* equivalent to a get of all data available */
202 }
203 
204 /*
205  * pl2303_buf_data_avail
206  *
207  * Return the number of bytes of data available in the circular
208  * buffer.
209  */
210 static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb)
211 {
212 	if (pb == NULL)
213 		return 0;
214 
215 	return ((pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size);
216 }
217 
218 /*
219  * pl2303_buf_space_avail
220  *
221  * Return the number of bytes of space available in the circular
222  * buffer.
223  */
224 static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb)
225 {
226 	if (pb == NULL)
227 		return 0;
228 
229 	return ((pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size);
230 }
231 
232 /*
233  * pl2303_buf_put
234  *
235  * Copy data data from a user buffer and put it into the circular buffer.
236  * Restrict to the amount of space available.
237  *
238  * Return the number of bytes copied.
239  */
240 static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
241 				   unsigned int count)
242 {
243 	unsigned int len;
244 
245 	if (pb == NULL)
246 		return 0;
247 
248 	len  = pl2303_buf_space_avail(pb);
249 	if (count > len)
250 		count = len;
251 
252 	if (count == 0)
253 		return 0;
254 
255 	len = pb->buf_buf + pb->buf_size - pb->buf_put;
256 	if (count > len) {
257 		memcpy(pb->buf_put, buf, len);
258 		memcpy(pb->buf_buf, buf+len, count - len);
259 		pb->buf_put = pb->buf_buf + count - len;
260 	} else {
261 		memcpy(pb->buf_put, buf, count);
262 		if (count < len)
263 			pb->buf_put += count;
264 		else /* count == len */
265 			pb->buf_put = pb->buf_buf;
266 	}
267 
268 	return count;
269 }
270 
271 /*
272  * pl2303_buf_get
273  *
274  * Get data from the circular buffer and copy to the given buffer.
275  * Restrict to the amount of data available.
276  *
277  * Return the number of bytes copied.
278  */
279 static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
280 				   unsigned int count)
281 {
282 	unsigned int len;
283 
284 	if (pb == NULL)
285 		return 0;
286 
287 	len = pl2303_buf_data_avail(pb);
288 	if (count > len)
289 		count = len;
290 
291 	if (count == 0)
292 		return 0;
293 
294 	len = pb->buf_buf + pb->buf_size - pb->buf_get;
295 	if (count > len) {
296 		memcpy(buf, pb->buf_get, len);
297 		memcpy(buf+len, pb->buf_buf, count - len);
298 		pb->buf_get = pb->buf_buf + count - len;
299 	} else {
300 		memcpy(buf, pb->buf_get, count);
301 		if (count < len)
302 			pb->buf_get += count;
303 		else /* count == len */
304 			pb->buf_get = pb->buf_buf;
305 	}
306 
307 	return count;
308 }
309 
310 static int pl2303_startup(struct usb_serial *serial)
311 {
312 	struct pl2303_private *priv;
313 	enum pl2303_type type = type_0;
314 	int i;
315 
316 	if (serial->dev->descriptor.bDeviceClass == 0x02)
317 		type = type_0;
318 	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
319 		type = HX;
320 	else if (serial->dev->descriptor.bDeviceClass == 0x00)
321 		type = type_1;
322 	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
323 		type = type_1;
324 	dbg("device type: %d", type);
325 
326 	for (i = 0; i < serial->num_ports; ++i) {
327 		priv = kzalloc(sizeof(struct pl2303_private), GFP_KERNEL);
328 		if (!priv)
329 			goto cleanup;
330 		spin_lock_init(&priv->lock);
331 		priv->buf = pl2303_buf_alloc(PL2303_BUF_SIZE);
332 		if (priv->buf == NULL) {
333 			kfree(priv);
334 			goto cleanup;
335 		}
336 		init_waitqueue_head(&priv->delta_msr_wait);
337 		priv->type = type;
338 		usb_set_serial_port_data(serial->port[i], priv);
339 	}
340 	return 0;
341 
342 cleanup:
343 	for (--i; i>=0; --i) {
344 		priv = usb_get_serial_port_data(serial->port[i]);
345 		pl2303_buf_free(priv->buf);
346 		kfree(priv);
347 		usb_set_serial_port_data(serial->port[i], NULL);
348 	}
349 	return -ENOMEM;
350 }
351 
352 static int set_control_lines(struct usb_device *dev, u8 value)
353 {
354 	int retval;
355 
356 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
357 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
358 				 value, 0, NULL, 0, 100);
359 	dbg("%s - value = %d, retval = %d", __FUNCTION__, value, retval);
360 	return retval;
361 }
362 
363 static void pl2303_send(struct usb_serial_port *port)
364 {
365 	int count, result;
366 	struct pl2303_private *priv = usb_get_serial_port_data(port);
367 	unsigned long flags;
368 
369 	dbg("%s - port %d", __FUNCTION__, port->number);
370 
371 	spin_lock_irqsave(&priv->lock, flags);
372 
373 	if (priv->write_urb_in_use) {
374 		spin_unlock_irqrestore(&priv->lock, flags);
375 		return;
376 	}
377 
378 	count = pl2303_buf_get(priv->buf, port->write_urb->transfer_buffer,
379 			       port->bulk_out_size);
380 
381 	if (count == 0) {
382 		spin_unlock_irqrestore(&priv->lock, flags);
383 		return;
384 	}
385 
386 	priv->write_urb_in_use = 1;
387 
388 	spin_unlock_irqrestore(&priv->lock, flags);
389 
390 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count,
391 			      port->write_urb->transfer_buffer);
392 
393 	port->write_urb->transfer_buffer_length = count;
394 	port->write_urb->dev = port->serial->dev;
395 	result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
396 	if (result) {
397 		dev_err(&port->dev, "%s - failed submitting write urb,"
398 			" error %d\n", __FUNCTION__, result);
399 		priv->write_urb_in_use = 0;
400 		// TODO: reschedule pl2303_send
401 	}
402 
403 	usb_serial_port_softint(port);
404 }
405 
406 static int pl2303_write(struct usb_serial_port *port, const unsigned char *buf,
407 			int count)
408 {
409 	struct pl2303_private *priv = usb_get_serial_port_data(port);
410 	unsigned long flags;
411 
412 	dbg("%s - port %d, %d bytes", __FUNCTION__, port->number, count);
413 
414 	if (!count)
415 		return count;
416 
417 	spin_lock_irqsave(&priv->lock, flags);
418 	count = pl2303_buf_put(priv->buf, buf, count);
419 	spin_unlock_irqrestore(&priv->lock, flags);
420 
421 	pl2303_send(port);
422 
423 	return count;
424 }
425 
426 static int pl2303_write_room(struct usb_serial_port *port)
427 {
428 	struct pl2303_private *priv = usb_get_serial_port_data(port);
429 	int room = 0;
430 	unsigned long flags;
431 
432 	dbg("%s - port %d", __FUNCTION__, port->number);
433 
434 	spin_lock_irqsave(&priv->lock, flags);
435 	room = pl2303_buf_space_avail(priv->buf);
436 	spin_unlock_irqrestore(&priv->lock, flags);
437 
438 	dbg("%s - returns %d", __FUNCTION__, room);
439 	return room;
440 }
441 
442 static int pl2303_chars_in_buffer(struct usb_serial_port *port)
443 {
444 	struct pl2303_private *priv = usb_get_serial_port_data(port);
445 	int chars = 0;
446 	unsigned long flags;
447 
448 	dbg("%s - port %d", __FUNCTION__, port->number);
449 
450 	spin_lock_irqsave(&priv->lock, flags);
451 	chars = pl2303_buf_data_avail(priv->buf);
452 	spin_unlock_irqrestore(&priv->lock, flags);
453 
454 	dbg("%s - returns %d", __FUNCTION__, chars);
455 	return chars;
456 }
457 
458 static void pl2303_set_termios(struct usb_serial_port *port,
459 			       struct ktermios *old_termios)
460 {
461 	struct usb_serial *serial = port->serial;
462 	struct pl2303_private *priv = usb_get_serial_port_data(port);
463 	unsigned long flags;
464 	unsigned int cflag;
465 	unsigned char *buf;
466 	int baud;
467 	int i;
468 	u8 control;
469 
470 	dbg("%s -  port %d", __FUNCTION__, port->number);
471 
472 	if ((!port->tty) || (!port->tty->termios)) {
473 		dbg("%s - no tty structures", __FUNCTION__);
474 		return;
475 	}
476 
477 	spin_lock_irqsave(&priv->lock, flags);
478 	if (!priv->termios_initialized) {
479 		*(port->tty->termios) = tty_std_termios;
480 		port->tty->termios->c_cflag = B9600 | CS8 | CREAD |
481 					      HUPCL | CLOCAL;
482 		priv->termios_initialized = 1;
483 	}
484 	spin_unlock_irqrestore(&priv->lock, flags);
485 
486 	cflag = port->tty->termios->c_cflag;
487 
488 	buf = kzalloc(7, GFP_KERNEL);
489 	if (!buf) {
490 		dev_err(&port->dev, "%s - out of memory.\n", __FUNCTION__);
491 		return;
492 	}
493 
494 	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
495 			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
496 			    0, 0, buf, 7, 100);
497 	dbg("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
498 	    buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
499 
500 	if (cflag & CSIZE) {
501 		switch (cflag & CSIZE) {
502 			case CS5:	buf[6] = 5;	break;
503 			case CS6:	buf[6] = 6;	break;
504 			case CS7:	buf[6] = 7;	break;
505 			default:
506 			case CS8:	buf[6] = 8;	break;
507 		}
508 		dbg("%s - data bits = %d", __FUNCTION__, buf[6]);
509 	}
510 
511 	baud = tty_get_baud_rate(port->tty);;
512 	dbg("%s - baud = %d", __FUNCTION__, baud);
513 	if (baud) {
514 		buf[0] = baud & 0xff;
515 		buf[1] = (baud >> 8) & 0xff;
516 		buf[2] = (baud >> 16) & 0xff;
517 		buf[3] = (baud >> 24) & 0xff;
518 	}
519 
520 	/* For reference buf[4]=0 is 1 stop bits */
521 	/* For reference buf[4]=1 is 1.5 stop bits */
522 	/* For reference buf[4]=2 is 2 stop bits */
523 	if (cflag & CSTOPB) {
524 		buf[4] = 2;
525 		dbg("%s - stop bits = 2", __FUNCTION__);
526 	} else {
527 		buf[4] = 0;
528 		dbg("%s - stop bits = 1", __FUNCTION__);
529 	}
530 
531 	if (cflag & PARENB) {
532 		/* For reference buf[5]=0 is none parity */
533 		/* For reference buf[5]=1 is odd parity */
534 		/* For reference buf[5]=2 is even parity */
535 		/* For reference buf[5]=3 is mark parity */
536 		/* For reference buf[5]=4 is space parity */
537 		if (cflag & PARODD) {
538 			buf[5] = 1;
539 			dbg("%s - parity = odd", __FUNCTION__);
540 		} else {
541 			buf[5] = 2;
542 			dbg("%s - parity = even", __FUNCTION__);
543 		}
544 	} else {
545 		buf[5] = 0;
546 		dbg("%s - parity = none", __FUNCTION__);
547 	}
548 
549 	i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
550 			    SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
551 			    0, 0, buf, 7, 100);
552 	dbg("0x21:0x20:0:0  %d", i);
553 
554 	/* change control lines if we are switching to or from B0 */
555 	spin_lock_irqsave(&priv->lock, flags);
556 	control = priv->line_control;
557 	if ((cflag & CBAUD) == B0)
558 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
559 	else
560 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
561 	if (control != priv->line_control) {
562 		control = priv->line_control;
563 		spin_unlock_irqrestore(&priv->lock, flags);
564 		set_control_lines(serial->dev, control);
565 	} else {
566 		spin_unlock_irqrestore(&priv->lock, flags);
567 	}
568 
569 	buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;
570 
571 	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
572 			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
573 			    0, 0, buf, 7, 100);
574 	dbg("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
575 	     buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
576 
577 	if (cflag & CRTSCTS) {
578 		__u16 index;
579 		if (priv->type == HX)
580 			index = 0x61;
581 		else
582 			index = 0x41;
583 		i = usb_control_msg(serial->dev,
584 				    usb_sndctrlpipe(serial->dev, 0),
585 				    VENDOR_WRITE_REQUEST,
586 				    VENDOR_WRITE_REQUEST_TYPE,
587 				    0x0, index, NULL, 0, 100);
588 		dbg("0x40:0x1:0x0:0x%x  %d", index, i);
589 	} else {
590 		i = usb_control_msg(serial->dev,
591 				    usb_sndctrlpipe(serial->dev, 0),
592 				    VENDOR_WRITE_REQUEST,
593 				    VENDOR_WRITE_REQUEST_TYPE,
594 				    0x0, 0x0, NULL, 0, 100);
595 		dbg ("0x40:0x1:0x0:0x0  %d", i);
596 	}
597 
598 	kfree(buf);
599 }
600 
601 static void pl2303_close(struct usb_serial_port *port, struct file *filp)
602 {
603 	struct pl2303_private *priv = usb_get_serial_port_data(port);
604 	unsigned long flags;
605 	unsigned int c_cflag;
606 	int bps;
607 	long timeout;
608 	wait_queue_t wait;
609 
610 	dbg("%s - port %d", __FUNCTION__, port->number);
611 
612 	/* wait for data to drain from the buffer */
613 	spin_lock_irqsave(&priv->lock, flags);
614 	timeout = PL2303_CLOSING_WAIT;
615 	init_waitqueue_entry(&wait, current);
616 	add_wait_queue(&port->tty->write_wait, &wait);
617 	for (;;) {
618 		set_current_state(TASK_INTERRUPTIBLE);
619 		if (pl2303_buf_data_avail(priv->buf) == 0 ||
620 		    timeout == 0 || signal_pending(current) ||
621 		    !usb_get_intfdata(port->serial->interface))	/* disconnect */
622 			break;
623 		spin_unlock_irqrestore(&priv->lock, flags);
624 		timeout = schedule_timeout(timeout);
625 		spin_lock_irqsave(&priv->lock, flags);
626 	}
627 	set_current_state(TASK_RUNNING);
628 	remove_wait_queue(&port->tty->write_wait, &wait);
629 	/* clear out any remaining data in the buffer */
630 	pl2303_buf_clear(priv->buf);
631 	spin_unlock_irqrestore(&priv->lock, flags);
632 
633 	/* wait for characters to drain from the device */
634 	/* (this is long enough for the entire 256 byte */
635 	/* pl2303 hardware buffer to drain with no flow */
636 	/* control for data rates of 1200 bps or more, */
637 	/* for lower rates we should really know how much */
638 	/* data is in the buffer to compute a delay */
639 	/* that is not unnecessarily long) */
640 	bps = tty_get_baud_rate(port->tty);
641 	if (bps > 1200)
642 		timeout = max((HZ*2560)/bps,HZ/10);
643 	else
644 		timeout = 2*HZ;
645 	schedule_timeout_interruptible(timeout);
646 
647 	/* shutdown our urbs */
648 	dbg("%s - shutting down urbs", __FUNCTION__);
649 	usb_kill_urb(port->write_urb);
650 	usb_kill_urb(port->read_urb);
651 	usb_kill_urb(port->interrupt_in_urb);
652 
653 	if (port->tty) {
654 		c_cflag = port->tty->termios->c_cflag;
655 		if (c_cflag & HUPCL) {
656 			/* drop DTR and RTS */
657 			spin_lock_irqsave(&priv->lock, flags);
658 			priv->line_control = 0;
659 			spin_unlock_irqrestore(&priv->lock, flags);
660 			set_control_lines(port->serial->dev, 0);
661 		}
662 	}
663 }
664 
665 static int pl2303_open(struct usb_serial_port *port, struct file *filp)
666 {
667 	struct ktermios tmp_termios;
668 	struct usb_serial *serial = port->serial;
669 	struct pl2303_private *priv = usb_get_serial_port_data(port);
670 	unsigned char *buf;
671 	int result;
672 
673 	dbg("%s -  port %d", __FUNCTION__, port->number);
674 
675 	if (priv->type != HX) {
676 		usb_clear_halt(serial->dev, port->write_urb->pipe);
677 		usb_clear_halt(serial->dev, port->read_urb->pipe);
678 	}
679 
680 	buf = kmalloc(10, GFP_KERNEL);
681 	if (buf==NULL)
682 		return -ENOMEM;
683 
684 #define FISH(a,b,c,d)								\
685 	result=usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev,0),	\
686 			       b, a, c, d, buf, 1, 100);			\
687 	dbg("0x%x:0x%x:0x%x:0x%x  %d - %x",a,b,c,d,result,buf[0]);
688 
689 #define SOUP(a,b,c,d)								\
690 	result=usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev,0),	\
691 			       b, a, c, d, NULL, 0, 100);			\
692 	dbg("0x%x:0x%x:0x%x:0x%x  %d",a,b,c,d,result);
693 
694 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
695 	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 0);
696 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
697 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
698 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
699 	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 1);
700 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
701 	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
702 	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0, 1);
703 	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 1, 0);
704 
705 	if (priv->type == HX) {
706 		/* HX chip */
707 		SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x44);
708 		/* reset upstream data pipes */
709           	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 8, 0);
710         	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 9, 0);
711 	} else {
712 		SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x24);
713 	}
714 
715 	kfree(buf);
716 
717 	/* Setup termios */
718 	if (port->tty) {
719 		pl2303_set_termios(port, &tmp_termios);
720 	}
721 
722 	//FIXME: need to assert RTS and DTR if CRTSCTS off
723 
724 	dbg("%s - submitting read urb", __FUNCTION__);
725 	port->read_urb->dev = serial->dev;
726 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
727 	if (result) {
728 		dev_err(&port->dev, "%s - failed submitting read urb,"
729 			" error %d\n", __FUNCTION__, result);
730 		pl2303_close(port, NULL);
731 		return -EPROTO;
732 	}
733 
734 	dbg("%s - submitting interrupt urb", __FUNCTION__);
735 	port->interrupt_in_urb->dev = serial->dev;
736 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
737 	if (result) {
738 		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
739 			" error %d\n", __FUNCTION__, result);
740 		pl2303_close(port, NULL);
741 		return -EPROTO;
742 	}
743 	return 0;
744 }
745 
746 static int pl2303_tiocmset(struct usb_serial_port *port, struct file *file,
747 			   unsigned int set, unsigned int clear)
748 {
749 	struct pl2303_private *priv = usb_get_serial_port_data(port);
750 	unsigned long flags;
751 	u8 control;
752 
753 	if (!usb_get_intfdata(port->serial->interface))
754 		return -ENODEV;
755 
756 	spin_lock_irqsave(&priv->lock, flags);
757 	if (set & TIOCM_RTS)
758 		priv->line_control |= CONTROL_RTS;
759 	if (set & TIOCM_DTR)
760 		priv->line_control |= CONTROL_DTR;
761 	if (clear & TIOCM_RTS)
762 		priv->line_control &= ~CONTROL_RTS;
763 	if (clear & TIOCM_DTR)
764 		priv->line_control &= ~CONTROL_DTR;
765 	control = priv->line_control;
766 	spin_unlock_irqrestore(&priv->lock, flags);
767 
768 	return set_control_lines(port->serial->dev, control);
769 }
770 
771 static int pl2303_tiocmget(struct usb_serial_port *port, struct file *file)
772 {
773 	struct pl2303_private *priv = usb_get_serial_port_data(port);
774 	unsigned long flags;
775 	unsigned int mcr;
776 	unsigned int status;
777 	unsigned int result;
778 
779 	dbg("%s (%d)", __FUNCTION__, port->number);
780 
781 	if (!usb_get_intfdata(port->serial->interface))
782 		return -ENODEV;
783 
784 	spin_lock_irqsave(&priv->lock, flags);
785 	mcr = priv->line_control;
786 	status = priv->line_status;
787 	spin_unlock_irqrestore(&priv->lock, flags);
788 
789 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
790 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
791 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
792 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
793 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
794 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
795 
796 	dbg("%s - result = %x", __FUNCTION__, result);
797 
798 	return result;
799 }
800 
801 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
802 {
803 	struct pl2303_private *priv = usb_get_serial_port_data(port);
804 	unsigned long flags;
805 	unsigned int prevstatus;
806 	unsigned int status;
807 	unsigned int changed;
808 
809 	spin_lock_irqsave(&priv->lock, flags);
810 	prevstatus = priv->line_status;
811 	spin_unlock_irqrestore(&priv->lock, flags);
812 
813 	while (1) {
814 		interruptible_sleep_on(&priv->delta_msr_wait);
815 		/* see if a signal did it */
816 		if (signal_pending(current))
817 			return -ERESTARTSYS;
818 
819 		spin_lock_irqsave(&priv->lock, flags);
820 		status = priv->line_status;
821 		spin_unlock_irqrestore(&priv->lock, flags);
822 
823 		changed=prevstatus^status;
824 
825 		if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
826 		    ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
827 		    ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
828 		    ((arg & TIOCM_CTS) && (changed & UART_CTS)) ) {
829 			return 0;
830 		}
831 		prevstatus = status;
832 	}
833 	/* NOTREACHED */
834 	return 0;
835 }
836 
837 static int pl2303_ioctl(struct usb_serial_port *port, struct file *file,
838 			unsigned int cmd, unsigned long arg)
839 {
840 	dbg("%s (%d) cmd = 0x%04x", __FUNCTION__, port->number, cmd);
841 
842 	switch (cmd) {
843 		case TIOCMIWAIT:
844 			dbg("%s (%d) TIOCMIWAIT", __FUNCTION__,  port->number);
845 			return wait_modem_info(port, arg);
846 
847 		default:
848 			dbg("%s not supported = 0x%04x", __FUNCTION__, cmd);
849 			break;
850 	}
851 
852 	return -ENOIOCTLCMD;
853 }
854 
855 static void pl2303_break_ctl(struct usb_serial_port *port, int break_state)
856 {
857 	struct usb_serial *serial = port->serial;
858 	u16 state;
859 	int result;
860 
861 	dbg("%s - port %d", __FUNCTION__, port->number);
862 
863 	if (break_state == 0)
864 		state = BREAK_OFF;
865 	else
866 		state = BREAK_ON;
867 	dbg("%s - turning break %s", __FUNCTION__, state==BREAK_OFF ? "off" : "on");
868 
869 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
870 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
871 				 0, NULL, 0, 100);
872 	if (result)
873 		dbg("%s - error sending break = %d", __FUNCTION__, result);
874 }
875 
876 static void pl2303_shutdown(struct usb_serial *serial)
877 {
878 	int i;
879 	struct pl2303_private *priv;
880 
881 	dbg("%s", __FUNCTION__);
882 
883 	for (i = 0; i < serial->num_ports; ++i) {
884 		priv = usb_get_serial_port_data(serial->port[i]);
885 		if (priv) {
886 			pl2303_buf_free(priv->buf);
887 			kfree(priv);
888 			usb_set_serial_port_data(serial->port[i], NULL);
889 		}
890 	}
891 }
892 
893 static void pl2303_update_line_status(struct usb_serial_port *port,
894 				      unsigned char *data,
895 				      unsigned int actual_length)
896 {
897 
898 	struct pl2303_private *priv = usb_get_serial_port_data(port);
899 	unsigned long flags;
900 	u8 status_idx = UART_STATE;
901 	u8 length = UART_STATE + 1;
902 	u16 idv, idp;
903 
904 	idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
905 	idp = le16_to_cpu(port->serial->dev->descriptor.idProduct);
906 
907 
908 	if (idv == SIEMENS_VENDOR_ID) {
909 		if (idp == SIEMENS_PRODUCT_ID_X65 ||
910 		    idp == SIEMENS_PRODUCT_ID_SX1 ||
911 		    idp == SIEMENS_PRODUCT_ID_X75) {
912 
913 			length = 1;
914 			status_idx = 0;
915 		}
916 	}
917 
918 	if (actual_length < length)
919 		return;
920 
921         /* Save off the uart status for others to look at */
922 	spin_lock_irqsave(&priv->lock, flags);
923 	priv->line_status = data[status_idx];
924 	spin_unlock_irqrestore(&priv->lock, flags);
925 	wake_up_interruptible(&priv->delta_msr_wait);
926 }
927 
928 static void pl2303_read_int_callback(struct urb *urb)
929 {
930 	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
931 	unsigned char *data = urb->transfer_buffer;
932 	unsigned int actual_length = urb->actual_length;
933 	int status = urb->status;
934 	int retval;
935 
936 	dbg("%s (%d)", __FUNCTION__, port->number);
937 
938 	switch (status) {
939 	case 0:
940 		/* success */
941 		break;
942 	case -ECONNRESET:
943 	case -ENOENT:
944 	case -ESHUTDOWN:
945 		/* this urb is terminated, clean up */
946 		dbg("%s - urb shutting down with status: %d", __FUNCTION__,
947 		    status);
948 		return;
949 	default:
950 		dbg("%s - nonzero urb status received: %d", __FUNCTION__,
951 		    status);
952 		goto exit;
953 	}
954 
955 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
956 			      urb->actual_length, urb->transfer_buffer);
957 
958 	pl2303_update_line_status(port, data, actual_length);
959 
960 exit:
961 	retval = usb_submit_urb(urb, GFP_ATOMIC);
962 	if (retval)
963 		dev_err(&urb->dev->dev,
964 			"%s - usb_submit_urb failed with result %d\n",
965 			__FUNCTION__, retval);
966 }
967 
968 static void pl2303_read_bulk_callback(struct urb *urb)
969 {
970 	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
971 	struct pl2303_private *priv = usb_get_serial_port_data(port);
972 	struct tty_struct *tty;
973 	unsigned char *data = urb->transfer_buffer;
974 	unsigned long flags;
975 	int i;
976 	int result;
977 	int status = urb->status;
978 	u8 line_status;
979 	char tty_flag;
980 
981 	dbg("%s - port %d", __FUNCTION__, port->number);
982 
983 	if (status) {
984 		dbg("%s - urb status = %d", __FUNCTION__, status);
985 		if (!port->open_count) {
986 			dbg("%s - port is closed, exiting.", __FUNCTION__);
987 			return;
988 		}
989 		if (status == -EPROTO) {
990 			/* PL2303 mysteriously fails with -EPROTO reschedule
991 			 * the read */
992 			dbg("%s - caught -EPROTO, resubmitting the urb",
993 			    __FUNCTION__);
994 			urb->dev = port->serial->dev;
995 			result = usb_submit_urb(urb, GFP_ATOMIC);
996 			if (result)
997 				dev_err(&urb->dev->dev, "%s - failed"
998 					" resubmitting read urb, error %d\n",
999 					__FUNCTION__, result);
1000 			return;
1001 		}
1002 		dbg("%s - unable to handle the error, exiting.", __FUNCTION__);
1003 		return;
1004 	}
1005 
1006 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
1007 			      urb->actual_length, data);
1008 
1009 	/* get tty_flag from status */
1010 	tty_flag = TTY_NORMAL;
1011 
1012 	spin_lock_irqsave(&priv->lock, flags);
1013 	line_status = priv->line_status;
1014 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1015 	spin_unlock_irqrestore(&priv->lock, flags);
1016 	wake_up_interruptible(&priv->delta_msr_wait);
1017 
1018 	/* break takes precedence over parity, */
1019 	/* which takes precedence over framing errors */
1020 	if (line_status & UART_BREAK_ERROR )
1021 		tty_flag = TTY_BREAK;
1022 	else if (line_status & UART_PARITY_ERROR)
1023 		tty_flag = TTY_PARITY;
1024 	else if (line_status & UART_FRAME_ERROR)
1025 		tty_flag = TTY_FRAME;
1026 	dbg("%s - tty_flag = %d", __FUNCTION__, tty_flag);
1027 
1028 	tty = port->tty;
1029 	if (tty && urb->actual_length) {
1030 		tty_buffer_request_room(tty, urb->actual_length + 1);
1031 		/* overrun is special, not associated with a char */
1032 		if (line_status & UART_OVERRUN_ERROR)
1033 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1034 		for (i = 0; i < urb->actual_length; ++i)
1035 			tty_insert_flip_char(tty, data[i], tty_flag);
1036 		tty_flip_buffer_push(tty);
1037 	}
1038 
1039 	/* Schedule the next read _if_ we are still open */
1040 	if (port->open_count) {
1041 		urb->dev = port->serial->dev;
1042 		result = usb_submit_urb(urb, GFP_ATOMIC);
1043 		if (result)
1044 			dev_err(&urb->dev->dev, "%s - failed resubmitting"
1045 				" read urb, error %d\n", __FUNCTION__, result);
1046 	}
1047 
1048 	return;
1049 }
1050 
1051 static void pl2303_write_bulk_callback(struct urb *urb)
1052 {
1053 	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
1054 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1055 	int result;
1056 	int status = urb->status;
1057 
1058 	dbg("%s - port %d", __FUNCTION__, port->number);
1059 
1060 	switch (status) {
1061 	case 0:
1062 		/* success */
1063 		break;
1064 	case -ECONNRESET:
1065 	case -ENOENT:
1066 	case -ESHUTDOWN:
1067 		/* this urb is terminated, clean up */
1068 		dbg("%s - urb shutting down with status: %d", __FUNCTION__,
1069 		    status);
1070 		priv->write_urb_in_use = 0;
1071 		return;
1072 	default:
1073 		/* error in the urb, so we have to resubmit it */
1074 		dbg("%s - Overflow in write", __FUNCTION__);
1075 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__,
1076 		    status);
1077 		port->write_urb->transfer_buffer_length = 1;
1078 		port->write_urb->dev = port->serial->dev;
1079 		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1080 		if (result)
1081 			dev_err(&urb->dev->dev, "%s - failed resubmitting write"
1082 				" urb, error %d\n", __FUNCTION__, result);
1083 		else
1084 			return;
1085 	}
1086 
1087 	priv->write_urb_in_use = 0;
1088 
1089 	/* send any buffered data */
1090 	pl2303_send(port);
1091 }
1092 
1093 /* All of the device info needed for the PL2303 SIO serial converter */
1094 static struct usb_serial_driver pl2303_device = {
1095 	.driver = {
1096 		.owner =	THIS_MODULE,
1097 		.name =		"pl2303",
1098 	},
1099 	.id_table =		id_table,
1100 	.usb_driver = 		&pl2303_driver,
1101 	.num_interrupt_in =	NUM_DONT_CARE,
1102 	.num_bulk_in =		1,
1103 	.num_bulk_out =		1,
1104 	.num_ports =		1,
1105 	.open =			pl2303_open,
1106 	.close =		pl2303_close,
1107 	.write =		pl2303_write,
1108 	.ioctl =		pl2303_ioctl,
1109 	.break_ctl =		pl2303_break_ctl,
1110 	.set_termios =		pl2303_set_termios,
1111 	.tiocmget =		pl2303_tiocmget,
1112 	.tiocmset =		pl2303_tiocmset,
1113 	.read_bulk_callback =	pl2303_read_bulk_callback,
1114 	.read_int_callback =	pl2303_read_int_callback,
1115 	.write_bulk_callback =	pl2303_write_bulk_callback,
1116 	.write_room =		pl2303_write_room,
1117 	.chars_in_buffer =	pl2303_chars_in_buffer,
1118 	.attach =		pl2303_startup,
1119 	.shutdown =		pl2303_shutdown,
1120 };
1121 
1122 static int __init pl2303_init(void)
1123 {
1124 	int retval;
1125 
1126 	retval = usb_serial_register(&pl2303_device);
1127 	if (retval)
1128 		goto failed_usb_serial_register;
1129 	retval = usb_register(&pl2303_driver);
1130 	if (retval)
1131 		goto failed_usb_register;
1132 	info(DRIVER_DESC);
1133 	return 0;
1134 failed_usb_register:
1135 	usb_serial_deregister(&pl2303_device);
1136 failed_usb_serial_register:
1137 	return retval;
1138 }
1139 
1140 static void __exit pl2303_exit(void)
1141 {
1142 	usb_deregister(&pl2303_driver);
1143 	usb_serial_deregister(&pl2303_device);
1144 }
1145 
1146 module_init(pl2303_init);
1147 module_exit(pl2303_exit);
1148 
1149 MODULE_DESCRIPTION(DRIVER_DESC);
1150 MODULE_LICENSE("GPL");
1151 
1152 module_param(debug, bool, S_IRUGO | S_IWUSR);
1153 MODULE_PARM_DESC(debug, "Debug enabled or not");
1154 
1155