xref: /openbmc/linux/drivers/usb/serial/pl2303.c (revision b34e08d5)
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
14  * driver
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/slab.h>
20 #include <linux/tty.h>
21 #include <linux/tty_driver.h>
22 #include <linux/tty_flip.h>
23 #include <linux/serial.h>
24 #include <linux/module.h>
25 #include <linux/moduleparam.h>
26 #include <linux/spinlock.h>
27 #include <linux/uaccess.h>
28 #include <linux/usb.h>
29 #include <linux/usb/serial.h>
30 #include <asm/unaligned.h>
31 #include "pl2303.h"
32 
33 
34 #define PL2303_QUIRK_UART_STATE_IDX0		BIT(0)
35 #define PL2303_QUIRK_LEGACY			BIT(1)
36 
37 static const struct usb_device_id id_table[] = {
38 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
39 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
40 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
41 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
42 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
43 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
44 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
45 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
46 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
47 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
48 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
49 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
50 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
51 	{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
52 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
53 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
54 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
55 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
56 	{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
57 	{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
58 	{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
59 	{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
60 	{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
61 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
62 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
63 	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
64 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
65 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
66 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
67 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
68 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
69 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
70 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
71 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
72 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
73 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
74 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
75 	{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
76 	{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
77 	{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
78 	{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
79 	{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
80 	{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID) },
81 	{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
82 	{ USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
83 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
84 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
85 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
86 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
87 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
88 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
89 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
90 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
91 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
92 	{ }					/* Terminating entry */
93 };
94 
95 MODULE_DEVICE_TABLE(usb, id_table);
96 
97 #define SET_LINE_REQUEST_TYPE		0x21
98 #define SET_LINE_REQUEST		0x20
99 
100 #define SET_CONTROL_REQUEST_TYPE	0x21
101 #define SET_CONTROL_REQUEST		0x22
102 #define CONTROL_DTR			0x01
103 #define CONTROL_RTS			0x02
104 
105 #define BREAK_REQUEST_TYPE		0x21
106 #define BREAK_REQUEST			0x23
107 #define BREAK_ON			0xffff
108 #define BREAK_OFF			0x0000
109 
110 #define GET_LINE_REQUEST_TYPE		0xa1
111 #define GET_LINE_REQUEST		0x21
112 
113 #define VENDOR_WRITE_REQUEST_TYPE	0x40
114 #define VENDOR_WRITE_REQUEST		0x01
115 
116 #define VENDOR_READ_REQUEST_TYPE	0xc0
117 #define VENDOR_READ_REQUEST		0x01
118 
119 #define UART_STATE_INDEX		8
120 #define UART_STATE_MSR_MASK		0x8b
121 #define UART_STATE_TRANSIENT_MASK	0x74
122 #define UART_DCD			0x01
123 #define UART_DSR			0x02
124 #define UART_BREAK_ERROR		0x04
125 #define UART_RING			0x08
126 #define UART_FRAME_ERROR		0x10
127 #define UART_PARITY_ERROR		0x20
128 #define UART_OVERRUN_ERROR		0x40
129 #define UART_CTS			0x80
130 
131 
132 enum pl2303_type {
133 	TYPE_01,	/* Type 0 and 1 (difference unknown) */
134 	TYPE_HX,	/* HX version of the pl2303 chip */
135 	TYPE_COUNT
136 };
137 
138 struct pl2303_type_data {
139 	speed_t max_baud_rate;
140 	unsigned long quirks;
141 };
142 
143 struct pl2303_serial_private {
144 	const struct pl2303_type_data *type;
145 	unsigned long quirks;
146 };
147 
148 struct pl2303_private {
149 	spinlock_t lock;
150 	u8 line_control;
151 	u8 line_status;
152 
153 	u8 line_settings[7];
154 };
155 
156 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
157 	[TYPE_01] = {
158 		.max_baud_rate =	1228800,
159 		.quirks =		PL2303_QUIRK_LEGACY,
160 	},
161 };
162 
163 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
164 							unsigned char buf[1])
165 {
166 	struct device *dev = &serial->interface->dev;
167 	int res;
168 
169 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
170 			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
171 			value, 0, buf, 1, 100);
172 	if (res != 1) {
173 		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
174 								value, res);
175 		if (res >= 0)
176 			res = -EIO;
177 
178 		return res;
179 	}
180 
181 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
182 
183 	return 0;
184 }
185 
186 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
187 {
188 	struct device *dev = &serial->interface->dev;
189 	int res;
190 
191 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
192 
193 	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
194 			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
195 			value, index, NULL, 0, 100);
196 	if (res) {
197 		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
198 								value, res);
199 		return res;
200 	}
201 
202 	return 0;
203 }
204 
205 static int pl2303_probe(struct usb_serial *serial,
206 					const struct usb_device_id *id)
207 {
208 	usb_set_serial_data(serial, (void *)id->driver_info);
209 
210 	return 0;
211 }
212 
213 static int pl2303_startup(struct usb_serial *serial)
214 {
215 	struct pl2303_serial_private *spriv;
216 	enum pl2303_type type = TYPE_01;
217 	unsigned char *buf;
218 
219 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
220 	if (!spriv)
221 		return -ENOMEM;
222 
223 	buf = kmalloc(1, GFP_KERNEL);
224 	if (!buf) {
225 		kfree(spriv);
226 		return -ENOMEM;
227 	}
228 
229 	if (serial->dev->descriptor.bDeviceClass == 0x02)
230 		type = TYPE_01;		/* type 0 */
231 	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
232 		type = TYPE_HX;
233 	else if (serial->dev->descriptor.bDeviceClass == 0x00)
234 		type = TYPE_01;		/* type 1 */
235 	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
236 		type = TYPE_01;		/* type 1 */
237 	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
238 
239 	spriv->type = &pl2303_type_data[type];
240 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
241 	spriv->quirks |= spriv->type->quirks;
242 
243 	usb_set_serial_data(serial, spriv);
244 
245 	pl2303_vendor_read(serial, 0x8484, buf);
246 	pl2303_vendor_write(serial, 0x0404, 0);
247 	pl2303_vendor_read(serial, 0x8484, buf);
248 	pl2303_vendor_read(serial, 0x8383, buf);
249 	pl2303_vendor_read(serial, 0x8484, buf);
250 	pl2303_vendor_write(serial, 0x0404, 1);
251 	pl2303_vendor_read(serial, 0x8484, buf);
252 	pl2303_vendor_read(serial, 0x8383, buf);
253 	pl2303_vendor_write(serial, 0, 1);
254 	pl2303_vendor_write(serial, 1, 0);
255 	if (spriv->quirks & PL2303_QUIRK_LEGACY)
256 		pl2303_vendor_write(serial, 2, 0x24);
257 	else
258 		pl2303_vendor_write(serial, 2, 0x44);
259 
260 	kfree(buf);
261 
262 	return 0;
263 }
264 
265 static void pl2303_release(struct usb_serial *serial)
266 {
267 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
268 
269 	kfree(spriv);
270 }
271 
272 static int pl2303_port_probe(struct usb_serial_port *port)
273 {
274 	struct pl2303_private *priv;
275 
276 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
277 	if (!priv)
278 		return -ENOMEM;
279 
280 	spin_lock_init(&priv->lock);
281 
282 	usb_set_serial_port_data(port, priv);
283 
284 	port->port.drain_delay = 256;
285 
286 	return 0;
287 }
288 
289 static int pl2303_port_remove(struct usb_serial_port *port)
290 {
291 	struct pl2303_private *priv = usb_get_serial_port_data(port);
292 
293 	kfree(priv);
294 
295 	return 0;
296 }
297 
298 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
299 {
300 	struct usb_device *dev = port->serial->dev;
301 	int retval;
302 
303 	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
304 
305 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
306 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
307 				 value, 0, NULL, 0, 100);
308 	if (retval)
309 		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
310 
311 	return retval;
312 }
313 
314 /*
315  * Returns the nearest supported baud rate that can be set directly without
316  * using divisors.
317  */
318 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
319 {
320 	static const speed_t baud_sup[] = {
321 		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
322 		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
323 		614400, 921600, 1228800, 2457600, 3000000, 6000000
324 	};
325 
326 	unsigned i;
327 
328 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
329 		if (baud_sup[i] > baud)
330 			break;
331 	}
332 
333 	if (i == ARRAY_SIZE(baud_sup))
334 		baud = baud_sup[i - 1];
335 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
336 		baud = baud_sup[i - 1];
337 	else
338 		baud = baud_sup[i];
339 
340 	return baud;
341 }
342 
343 /*
344  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
345  *       use 9600 baud.
346  */
347 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
348 								speed_t baud)
349 {
350 	put_unaligned_le32(baud, buf);
351 
352 	return baud;
353 }
354 
355 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
356 								speed_t baud)
357 {
358 	unsigned int tmp;
359 
360 	/*
361 	 * Apparently the formula is:
362 	 * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
363 	 */
364 	tmp = 12000000 * 32 / baud;
365 	buf[3] = 0x80;
366 	buf[2] = 0;
367 	buf[1] = (tmp >= 256);
368 	while (tmp >= 256) {
369 		tmp >>= 2;
370 		buf[1] <<= 1;
371 	}
372 	buf[0] = tmp;
373 
374 	return baud;
375 }
376 
377 static void pl2303_encode_baud_rate(struct tty_struct *tty,
378 					struct usb_serial_port *port,
379 					u8 buf[4])
380 {
381 	struct usb_serial *serial = port->serial;
382 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
383 	speed_t	baud_sup;
384 	speed_t baud;
385 
386 	baud = tty_get_baud_rate(tty);
387 	dev_dbg(&port->dev, "baud requested = %u\n", baud);
388 	if (!baud)
389 		return;
390 
391 	if (spriv->type->max_baud_rate)
392 		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
393 	/*
394 	 * Set baud rate to nearest supported value.
395 	 *
396 	 * NOTE: Baud rate 500k can only be set using divisors.
397 	 */
398 	baud_sup = pl2303_get_supported_baud_rate(baud);
399 
400 	if (baud == 500000)
401 		baud = pl2303_encode_baud_rate_divisor(buf, baud);
402 	else
403 		baud = pl2303_encode_baud_rate_direct(buf, baud_sup);
404 
405 	/* Save resulting baud rate */
406 	tty_encode_baud_rate(tty, baud, baud);
407 	dev_dbg(&port->dev, "baud set = %u\n", baud);
408 }
409 
410 static int pl2303_get_line_request(struct usb_serial_port *port,
411 							unsigned char buf[7])
412 {
413 	struct usb_device *udev = port->serial->dev;
414 	int ret;
415 
416 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
417 				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
418 				0, 0, buf, 7, 100);
419 	if (ret != 7) {
420 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
421 
422 		if (ret > 0)
423 			ret = -EIO;
424 
425 		return ret;
426 	}
427 
428 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
429 
430 	return 0;
431 }
432 
433 static int pl2303_set_line_request(struct usb_serial_port *port,
434 							unsigned char buf[7])
435 {
436 	struct usb_device *udev = port->serial->dev;
437 	int ret;
438 
439 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
440 				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
441 				0, 0, buf, 7, 100);
442 	if (ret != 7) {
443 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
444 
445 		if (ret > 0)
446 			ret = -EIO;
447 
448 		return ret;
449 	}
450 
451 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
452 
453 	return 0;
454 }
455 
456 static void pl2303_set_termios(struct tty_struct *tty,
457 		struct usb_serial_port *port, struct ktermios *old_termios)
458 {
459 	struct usb_serial *serial = port->serial;
460 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
461 	struct pl2303_private *priv = usb_get_serial_port_data(port);
462 	unsigned long flags;
463 	unsigned char *buf;
464 	int ret;
465 	u8 control;
466 
467 	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
468 		return;
469 
470 	buf = kzalloc(7, GFP_KERNEL);
471 	if (!buf) {
472 		/* Report back no change occurred */
473 		if (old_termios)
474 			tty->termios = *old_termios;
475 		return;
476 	}
477 
478 	pl2303_get_line_request(port, buf);
479 
480 	switch (C_CSIZE(tty)) {
481 	case CS5:
482 		buf[6] = 5;
483 		break;
484 	case CS6:
485 		buf[6] = 6;
486 		break;
487 	case CS7:
488 		buf[6] = 7;
489 		break;
490 	default:
491 	case CS8:
492 		buf[6] = 8;
493 	}
494 	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
495 
496 	/* For reference buf[0]:buf[3] baud rate value */
497 	pl2303_encode_baud_rate(tty, port, &buf[0]);
498 
499 	/* For reference buf[4]=0 is 1 stop bits */
500 	/* For reference buf[4]=1 is 1.5 stop bits */
501 	/* For reference buf[4]=2 is 2 stop bits */
502 	if (C_CSTOPB(tty)) {
503 		/*
504 		 * NOTE: Comply with "real" UARTs / RS232:
505 		 *       use 1.5 instead of 2 stop bits with 5 data bits
506 		 */
507 		if (C_CSIZE(tty) == CS5) {
508 			buf[4] = 1;
509 			dev_dbg(&port->dev, "stop bits = 1.5\n");
510 		} else {
511 			buf[4] = 2;
512 			dev_dbg(&port->dev, "stop bits = 2\n");
513 		}
514 	} else {
515 		buf[4] = 0;
516 		dev_dbg(&port->dev, "stop bits = 1\n");
517 	}
518 
519 	if (C_PARENB(tty)) {
520 		/* For reference buf[5]=0 is none parity */
521 		/* For reference buf[5]=1 is odd parity */
522 		/* For reference buf[5]=2 is even parity */
523 		/* For reference buf[5]=3 is mark parity */
524 		/* For reference buf[5]=4 is space parity */
525 		if (C_PARODD(tty)) {
526 			if (C_CMSPAR(tty)) {
527 				buf[5] = 3;
528 				dev_dbg(&port->dev, "parity = mark\n");
529 			} else {
530 				buf[5] = 1;
531 				dev_dbg(&port->dev, "parity = odd\n");
532 			}
533 		} else {
534 			if (C_CMSPAR(tty)) {
535 				buf[5] = 4;
536 				dev_dbg(&port->dev, "parity = space\n");
537 			} else {
538 				buf[5] = 2;
539 				dev_dbg(&port->dev, "parity = even\n");
540 			}
541 		}
542 	} else {
543 		buf[5] = 0;
544 		dev_dbg(&port->dev, "parity = none\n");
545 	}
546 
547 	/*
548 	 * Some PL2303 are known to lose bytes if you change serial settings
549 	 * even to the same values as before. Thus we actually need to filter
550 	 * in this specific case.
551 	 *
552 	 * Note that the tty_termios_hw_change check above is not sufficient
553 	 * as a previously requested baud rate may differ from the one
554 	 * actually used (and stored in old_termios).
555 	 *
556 	 * NOTE: No additional locking needed for line_settings as it is
557 	 *       only used in set_termios, which is serialised against itself.
558 	 */
559 	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
560 		ret = pl2303_set_line_request(port, buf);
561 		if (!ret)
562 			memcpy(priv->line_settings, buf, 7);
563 	}
564 
565 	/* change control lines if we are switching to or from B0 */
566 	spin_lock_irqsave(&priv->lock, flags);
567 	control = priv->line_control;
568 	if (C_BAUD(tty) == B0)
569 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
570 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
571 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
572 	if (control != priv->line_control) {
573 		control = priv->line_control;
574 		spin_unlock_irqrestore(&priv->lock, flags);
575 		pl2303_set_control_lines(port, control);
576 	} else {
577 		spin_unlock_irqrestore(&priv->lock, flags);
578 	}
579 
580 	if (C_CRTSCTS(tty)) {
581 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
582 			pl2303_vendor_write(serial, 0x0, 0x41);
583 		else
584 			pl2303_vendor_write(serial, 0x0, 0x61);
585 	} else {
586 		pl2303_vendor_write(serial, 0x0, 0x0);
587 	}
588 
589 	kfree(buf);
590 }
591 
592 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
593 {
594 	struct pl2303_private *priv = usb_get_serial_port_data(port);
595 	unsigned long flags;
596 	u8 control;
597 
598 	spin_lock_irqsave(&priv->lock, flags);
599 	if (on)
600 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
601 	else
602 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
603 	control = priv->line_control;
604 	spin_unlock_irqrestore(&priv->lock, flags);
605 
606 	pl2303_set_control_lines(port, control);
607 }
608 
609 static void pl2303_close(struct usb_serial_port *port)
610 {
611 	usb_serial_generic_close(port);
612 	usb_kill_urb(port->interrupt_in_urb);
613 }
614 
615 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
616 {
617 	struct usb_serial *serial = port->serial;
618 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
619 	int result;
620 
621 	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
622 		usb_clear_halt(serial->dev, port->write_urb->pipe);
623 		usb_clear_halt(serial->dev, port->read_urb->pipe);
624 	} else {
625 		/* reset upstream data pipes */
626 		pl2303_vendor_write(serial, 8, 0);
627 		pl2303_vendor_write(serial, 9, 0);
628 	}
629 
630 	/* Setup termios */
631 	if (tty)
632 		pl2303_set_termios(tty, port, NULL);
633 
634 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
635 	if (result) {
636 		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
637 			result);
638 		return result;
639 	}
640 
641 	result = usb_serial_generic_open(tty, port);
642 	if (result) {
643 		usb_kill_urb(port->interrupt_in_urb);
644 		return result;
645 	}
646 
647 	return 0;
648 }
649 
650 static int pl2303_tiocmset(struct tty_struct *tty,
651 			   unsigned int set, unsigned int clear)
652 {
653 	struct usb_serial_port *port = tty->driver_data;
654 	struct pl2303_private *priv = usb_get_serial_port_data(port);
655 	unsigned long flags;
656 	u8 control;
657 	int ret;
658 
659 	spin_lock_irqsave(&priv->lock, flags);
660 	if (set & TIOCM_RTS)
661 		priv->line_control |= CONTROL_RTS;
662 	if (set & TIOCM_DTR)
663 		priv->line_control |= CONTROL_DTR;
664 	if (clear & TIOCM_RTS)
665 		priv->line_control &= ~CONTROL_RTS;
666 	if (clear & TIOCM_DTR)
667 		priv->line_control &= ~CONTROL_DTR;
668 	control = priv->line_control;
669 	spin_unlock_irqrestore(&priv->lock, flags);
670 
671 	ret = pl2303_set_control_lines(port, control);
672 	if (ret)
673 		return usb_translate_errors(ret);
674 
675 	return 0;
676 }
677 
678 static int pl2303_tiocmget(struct tty_struct *tty)
679 {
680 	struct usb_serial_port *port = tty->driver_data;
681 	struct pl2303_private *priv = usb_get_serial_port_data(port);
682 	unsigned long flags;
683 	unsigned int mcr;
684 	unsigned int status;
685 	unsigned int result;
686 
687 	spin_lock_irqsave(&priv->lock, flags);
688 	mcr = priv->line_control;
689 	status = priv->line_status;
690 	spin_unlock_irqrestore(&priv->lock, flags);
691 
692 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
693 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
694 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
695 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
696 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
697 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
698 
699 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
700 
701 	return result;
702 }
703 
704 static int pl2303_carrier_raised(struct usb_serial_port *port)
705 {
706 	struct pl2303_private *priv = usb_get_serial_port_data(port);
707 
708 	if (priv->line_status & UART_DCD)
709 		return 1;
710 
711 	return 0;
712 }
713 
714 static int pl2303_ioctl(struct tty_struct *tty,
715 			unsigned int cmd, unsigned long arg)
716 {
717 	struct serial_struct ser;
718 	struct usb_serial_port *port = tty->driver_data;
719 
720 	switch (cmd) {
721 	case TIOCGSERIAL:
722 		memset(&ser, 0, sizeof ser);
723 		ser.type = PORT_16654;
724 		ser.line = port->minor;
725 		ser.port = port->port_number;
726 		ser.baud_base = 460800;
727 
728 		if (copy_to_user((void __user *)arg, &ser, sizeof ser))
729 			return -EFAULT;
730 
731 		return 0;
732 	default:
733 		break;
734 	}
735 
736 	return -ENOIOCTLCMD;
737 }
738 
739 static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
740 {
741 	struct usb_serial_port *port = tty->driver_data;
742 	struct usb_serial *serial = port->serial;
743 	u16 state;
744 	int result;
745 
746 	if (break_state == 0)
747 		state = BREAK_OFF;
748 	else
749 		state = BREAK_ON;
750 
751 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
752 			state == BREAK_OFF ? "off" : "on");
753 
754 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
755 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
756 				 0, NULL, 0, 100);
757 	if (result)
758 		dev_err(&port->dev, "error sending break = %d\n", result);
759 }
760 
761 static void pl2303_update_line_status(struct usb_serial_port *port,
762 				      unsigned char *data,
763 				      unsigned int actual_length)
764 {
765 	struct usb_serial *serial = port->serial;
766 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
767 	struct pl2303_private *priv = usb_get_serial_port_data(port);
768 	struct tty_struct *tty;
769 	unsigned long flags;
770 	unsigned int status_idx = UART_STATE_INDEX;
771 	u8 status;
772 	u8 delta;
773 
774 	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
775 		status_idx = 0;
776 
777 	if (actual_length < status_idx + 1)
778 		return;
779 
780 	status = data[status_idx];
781 
782 	/* Save off the uart status for others to look at */
783 	spin_lock_irqsave(&priv->lock, flags);
784 	delta = priv->line_status ^ status;
785 	priv->line_status = status;
786 	spin_unlock_irqrestore(&priv->lock, flags);
787 
788 	if (status & UART_BREAK_ERROR)
789 		usb_serial_handle_break(port);
790 
791 	if (delta & UART_STATE_MSR_MASK) {
792 		if (delta & UART_CTS)
793 			port->icount.cts++;
794 		if (delta & UART_DSR)
795 			port->icount.dsr++;
796 		if (delta & UART_RING)
797 			port->icount.rng++;
798 		if (delta & UART_DCD) {
799 			port->icount.dcd++;
800 			tty = tty_port_tty_get(&port->port);
801 			if (tty) {
802 				usb_serial_handle_dcd_change(port, tty,
803 							status & UART_DCD);
804 				tty_kref_put(tty);
805 			}
806 		}
807 
808 		wake_up_interruptible(&port->port.delta_msr_wait);
809 	}
810 }
811 
812 static void pl2303_read_int_callback(struct urb *urb)
813 {
814 	struct usb_serial_port *port =  urb->context;
815 	unsigned char *data = urb->transfer_buffer;
816 	unsigned int actual_length = urb->actual_length;
817 	int status = urb->status;
818 	int retval;
819 
820 	switch (status) {
821 	case 0:
822 		/* success */
823 		break;
824 	case -ECONNRESET:
825 	case -ENOENT:
826 	case -ESHUTDOWN:
827 		/* this urb is terminated, clean up */
828 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
829 			__func__, status);
830 		return;
831 	default:
832 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
833 			__func__, status);
834 		goto exit;
835 	}
836 
837 	usb_serial_debug_data(&port->dev, __func__,
838 			      urb->actual_length, urb->transfer_buffer);
839 
840 	pl2303_update_line_status(port, data, actual_length);
841 
842 exit:
843 	retval = usb_submit_urb(urb, GFP_ATOMIC);
844 	if (retval) {
845 		dev_err(&port->dev,
846 			"%s - usb_submit_urb failed with result %d\n",
847 			__func__, retval);
848 	}
849 }
850 
851 static void pl2303_process_read_urb(struct urb *urb)
852 {
853 	struct usb_serial_port *port = urb->context;
854 	struct pl2303_private *priv = usb_get_serial_port_data(port);
855 	unsigned char *data = urb->transfer_buffer;
856 	char tty_flag = TTY_NORMAL;
857 	unsigned long flags;
858 	u8 line_status;
859 	int i;
860 
861 	/* update line status */
862 	spin_lock_irqsave(&priv->lock, flags);
863 	line_status = priv->line_status;
864 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
865 	spin_unlock_irqrestore(&priv->lock, flags);
866 
867 	if (!urb->actual_length)
868 		return;
869 
870 	/*
871 	 * Break takes precedence over parity, which takes precedence over
872 	 * framing errors.
873 	 */
874 	if (line_status & UART_BREAK_ERROR)
875 		tty_flag = TTY_BREAK;
876 	else if (line_status & UART_PARITY_ERROR)
877 		tty_flag = TTY_PARITY;
878 	else if (line_status & UART_FRAME_ERROR)
879 		tty_flag = TTY_FRAME;
880 
881 	if (tty_flag != TTY_NORMAL)
882 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
883 								tty_flag);
884 	/* overrun is special, not associated with a char */
885 	if (line_status & UART_OVERRUN_ERROR)
886 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
887 
888 	if (port->port.console && port->sysrq) {
889 		for (i = 0; i < urb->actual_length; ++i)
890 			if (!usb_serial_handle_sysrq_char(port, data[i]))
891 				tty_insert_flip_char(&port->port, data[i],
892 						tty_flag);
893 	} else {
894 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
895 							urb->actual_length);
896 	}
897 
898 	tty_flip_buffer_push(&port->port);
899 }
900 
901 static struct usb_serial_driver pl2303_device = {
902 	.driver = {
903 		.owner =	THIS_MODULE,
904 		.name =		"pl2303",
905 	},
906 	.id_table =		id_table,
907 	.num_ports =		1,
908 	.bulk_in_size =		256,
909 	.bulk_out_size =	256,
910 	.open =			pl2303_open,
911 	.close =		pl2303_close,
912 	.dtr_rts =		pl2303_dtr_rts,
913 	.carrier_raised =	pl2303_carrier_raised,
914 	.ioctl =		pl2303_ioctl,
915 	.break_ctl =		pl2303_break_ctl,
916 	.set_termios =		pl2303_set_termios,
917 	.tiocmget =		pl2303_tiocmget,
918 	.tiocmset =		pl2303_tiocmset,
919 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
920 	.process_read_urb =	pl2303_process_read_urb,
921 	.read_int_callback =	pl2303_read_int_callback,
922 	.probe =		pl2303_probe,
923 	.attach =		pl2303_startup,
924 	.release =		pl2303_release,
925 	.port_probe =		pl2303_port_probe,
926 	.port_remove =		pl2303_port_remove,
927 };
928 
929 static struct usb_serial_driver * const serial_drivers[] = {
930 	&pl2303_device, NULL
931 };
932 
933 module_usb_serial_driver(serial_drivers, id_table);
934 
935 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
936 MODULE_LICENSE("GPL");
937