xref: /openbmc/linux/drivers/usb/serial/pl2303.c (revision f7777dcc)
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  * Copyright (C) 2009, 2013 Frank Schäfer <fschaefer.oss@googlemail.com>
8  *  - fixes, improvements and documentation for the baud rate encoding methods
9  * Copyright (C) 2013 Reinhard Max <max@suse.de>
10  *  - fixes and improvements for the divisor based baud rate encoding method
11  *
12  * Original driver for 2.2.x by anonymous
13  *
14  *	This program is free software; you can redistribute it and/or
15  *	modify it under the terms of the GNU General Public License version
16  *	2 as published by the Free Software Foundation.
17  *
18  * See Documentation/usb/usb-serial.txt for more information on using this
19  * driver
20  *
21  */
22 
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/tty.h>
28 #include <linux/tty_driver.h>
29 #include <linux/tty_flip.h>
30 #include <linux/serial.h>
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/spinlock.h>
34 #include <linux/uaccess.h>
35 #include <linux/usb.h>
36 #include <linux/usb/serial.h>
37 #include <asm/unaligned.h>
38 #include "pl2303.h"
39 
40 /*
41  * Version Information
42  */
43 #define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"
44 
45 static const struct usb_device_id id_table[] = {
46 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
47 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
48 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
49 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
50 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
51 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
52 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
53 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
54 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
55 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
56 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
57 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
58 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
59 	{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
60 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
61 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
62 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
63 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
64 	{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
65 	{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
66 	{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
67 	{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
68 	{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
69 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
70 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
71 	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
72 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
73 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
74 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
75 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
76 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
77 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
78 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
79 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
80 	{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
81 	{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
82 	{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
83 	{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
84 	{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
85 	{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID) },
86 	{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
87 	{ USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
88 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
89 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
90 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
91 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
92 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
93 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
94 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
95 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
96 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
97 	{ }					/* Terminating entry */
98 };
99 
100 MODULE_DEVICE_TABLE(usb, id_table);
101 
102 #define SET_LINE_REQUEST_TYPE		0x21
103 #define SET_LINE_REQUEST		0x20
104 
105 #define SET_CONTROL_REQUEST_TYPE	0x21
106 #define SET_CONTROL_REQUEST		0x22
107 #define CONTROL_DTR			0x01
108 #define CONTROL_RTS			0x02
109 
110 #define BREAK_REQUEST_TYPE		0x21
111 #define BREAK_REQUEST			0x23
112 #define BREAK_ON			0xffff
113 #define BREAK_OFF			0x0000
114 
115 #define GET_LINE_REQUEST_TYPE		0xa1
116 #define GET_LINE_REQUEST		0x21
117 
118 #define VENDOR_WRITE_REQUEST_TYPE	0x40
119 #define VENDOR_WRITE_REQUEST		0x01
120 
121 #define VENDOR_READ_REQUEST_TYPE	0xc0
122 #define VENDOR_READ_REQUEST		0x01
123 
124 #define UART_STATE			0x08
125 #define UART_STATE_TRANSIENT_MASK	0x74
126 #define UART_DCD			0x01
127 #define UART_DSR			0x02
128 #define UART_BREAK_ERROR		0x04
129 #define UART_RING			0x08
130 #define UART_FRAME_ERROR		0x10
131 #define UART_PARITY_ERROR		0x20
132 #define UART_OVERRUN_ERROR		0x40
133 #define UART_CTS			0x80
134 
135 
136 enum pl2303_type {
137 	type_0,		/* H version ? */
138 	type_1,		/* H version ? */
139 	HX_TA,		/* HX(A) / X(A) / TA version  */ /* TODO: improve */
140 	HXD_EA_RA_SA,	/* HXD / EA / RA / SA version */ /* TODO: improve */
141 	TB,		/* TB version */
142 	HX_CLONE,	/* Cheap and less functional clone of the HX chip */
143 };
144 /*
145  * NOTE: don't know the difference between type 0 and type 1,
146  * until someone from Prolific tells us...
147  * TODO: distinguish between X/HX, TA and HXD, EA, RA, SA variants
148  */
149 
150 struct pl2303_serial_private {
151 	enum pl2303_type type;
152 };
153 
154 struct pl2303_private {
155 	spinlock_t lock;
156 	u8 line_control;
157 	u8 line_status;
158 };
159 
160 static int pl2303_vendor_read(__u16 value, __u16 index,
161 		struct usb_serial *serial, unsigned char *buf)
162 {
163 	int res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
164 			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
165 			value, index, buf, 1, 100);
166 	dev_dbg(&serial->interface->dev, "0x%x:0x%x:0x%x:0x%x  %d - %x\n",
167 		VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, value, index,
168 		res, buf[0]);
169 	return res;
170 }
171 
172 static int pl2303_vendor_write(__u16 value, __u16 index,
173 		struct usb_serial *serial)
174 {
175 	int res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
176 			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
177 			value, index, NULL, 0, 100);
178 	dev_dbg(&serial->interface->dev, "0x%x:0x%x:0x%x:0x%x  %d\n",
179 		VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, value, index,
180 		res);
181 	return res;
182 }
183 
184 static int pl2303_startup(struct usb_serial *serial)
185 {
186 	struct pl2303_serial_private *spriv;
187 	enum pl2303_type type = type_0;
188 	char *type_str = "unknown (treating as type_0)";
189 	unsigned char *buf;
190 
191 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
192 	if (!spriv)
193 		return -ENOMEM;
194 
195 	buf = kmalloc(10, GFP_KERNEL);
196 	if (!buf) {
197 		kfree(spriv);
198 		return -ENOMEM;
199 	}
200 
201 	if (serial->dev->descriptor.bDeviceClass == 0x02) {
202 		type = type_0;
203 		type_str = "type_0";
204 	} else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40) {
205 		/*
206 		 * NOTE: The bcdDevice version is the only difference between
207 		 * the device descriptors of the X/HX, HXD, EA, RA, SA, TA, TB
208 		 */
209 		if (le16_to_cpu(serial->dev->descriptor.bcdDevice) == 0x300) {
210 			/* Check if the device is a clone */
211 			pl2303_vendor_read(0x9494, 0, serial, buf);
212 			/*
213 			 * NOTE: Not sure if this read is really needed.
214 			 * The HX returns 0x00, the clone 0x02, but the Windows
215 			 * driver seems to ignore the value and continues.
216 			 */
217 			pl2303_vendor_write(0x0606, 0xaa, serial);
218 			pl2303_vendor_read(0x8686, 0, serial, buf);
219 			if (buf[0] != 0xaa) {
220 				type = HX_CLONE;
221 				type_str = "X/HX clone (limited functionality)";
222 			} else {
223 				type = HX_TA;
224 				type_str = "X/HX/TA";
225 			}
226 			pl2303_vendor_write(0x0606, 0x00, serial);
227 		} else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
228 								     == 0x400) {
229 			type = HXD_EA_RA_SA;
230 			type_str = "HXD/EA/RA/SA";
231 		} else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
232 								     == 0x500) {
233 			type = TB;
234 			type_str = "TB";
235 		} else {
236 			dev_info(&serial->interface->dev,
237 					   "unknown/unsupported device type\n");
238 			kfree(spriv);
239 			kfree(buf);
240 			return -ENODEV;
241 		}
242 	} else if (serial->dev->descriptor.bDeviceClass == 0x00
243 		   || serial->dev->descriptor.bDeviceClass == 0xFF) {
244 		type = type_1;
245 		type_str = "type_1";
246 	}
247 	dev_dbg(&serial->interface->dev, "device type: %s\n", type_str);
248 
249 	spriv->type = type;
250 	usb_set_serial_data(serial, spriv);
251 
252 	pl2303_vendor_read(0x8484, 0, serial, buf);
253 	pl2303_vendor_write(0x0404, 0, serial);
254 	pl2303_vendor_read(0x8484, 0, serial, buf);
255 	pl2303_vendor_read(0x8383, 0, serial, buf);
256 	pl2303_vendor_read(0x8484, 0, serial, buf);
257 	pl2303_vendor_write(0x0404, 1, serial);
258 	pl2303_vendor_read(0x8484, 0, serial, buf);
259 	pl2303_vendor_read(0x8383, 0, serial, buf);
260 	pl2303_vendor_write(0, 1, serial);
261 	pl2303_vendor_write(1, 0, serial);
262 	if (type == type_0 || type == type_1)
263 		pl2303_vendor_write(2, 0x24, serial);
264 	else
265 		pl2303_vendor_write(2, 0x44, serial);
266 
267 	kfree(buf);
268 	return 0;
269 }
270 
271 static void pl2303_release(struct usb_serial *serial)
272 {
273 	struct pl2303_serial_private *spriv;
274 
275 	spriv = usb_get_serial_data(serial);
276 	kfree(spriv);
277 }
278 
279 static int pl2303_port_probe(struct usb_serial_port *port)
280 {
281 	struct pl2303_private *priv;
282 
283 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
284 	if (!priv)
285 		return -ENOMEM;
286 
287 	spin_lock_init(&priv->lock);
288 
289 	usb_set_serial_port_data(port, priv);
290 
291 	port->port.drain_delay = 256;
292 
293 	return 0;
294 }
295 
296 static int pl2303_port_remove(struct usb_serial_port *port)
297 {
298 	struct pl2303_private *priv;
299 
300 	priv = usb_get_serial_port_data(port);
301 	kfree(priv);
302 
303 	return 0;
304 }
305 
306 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
307 {
308 	struct usb_device *dev = port->serial->dev;
309 	int retval;
310 
311 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
312 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
313 				 value, 0, NULL, 0, 100);
314 	dev_dbg(&port->dev, "%s - value = %d, retval = %d\n", __func__,
315 		value, retval);
316 	return retval;
317 }
318 
319 static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type,
320 								      u8 buf[4])
321 {
322 	/*
323 	 * NOTE: Only the values defined in baud_sup are supported !
324 	 * => if unsupported values are set, the PL2303 uses 9600 baud instead
325 	 * => HX clones just don't work at unsupported baud rates < 115200 baud,
326 	 *    for baud rates > 115200 they run at 115200 baud
327 	 */
328 	const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
329 				 4800, 7200, 9600, 14400, 19200, 28800, 38400,
330 				 57600, 115200, 230400, 460800, 614400, 921600,
331 				 1228800, 2457600, 3000000, 6000000, 12000000 };
332 	/*
333 	 * NOTE: With the exception of type_0/1 devices, the following
334 	 * additional baud rates are supported (tested with HX rev. 3A only):
335 	 * 110*, 56000*, 128000, 134400, 161280, 201600, 256000*, 268800,
336 	 * 403200, 806400.	(*: not HX and HX clones)
337 	 *
338 	 * Maximum values: HXD, TB: 12000000; HX, TA: 6000000;
339 	 *                 type_0+1: 1228800; RA: 921600; HX clones, SA: 115200
340 	 *
341 	 * As long as we are not using this encoding method for anything else
342 	 * than the type_0+1, HX and HX clone chips, there is no point in
343 	 * complicating the code to support them.
344 	 */
345 	int i;
346 
347 	/* Set baudrate to nearest supported value */
348 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
349 		if (baud_sup[i] > baud)
350 			break;
351 	}
352 	if (i == ARRAY_SIZE(baud_sup))
353 		baud = baud_sup[i - 1];
354 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
355 		baud = baud_sup[i - 1];
356 	else
357 		baud = baud_sup[i];
358 	/* Respect the chip type specific baud rate limits */
359 	/*
360 	 * FIXME: as long as we don't know how to distinguish between the
361 	 * HXD, EA, RA, and SA chip variants, allow the max. value of 12M.
362 	 */
363 	if (type == HX_TA)
364 		baud = min_t(int, baud, 6000000);
365 	else if (type == type_0 || type == type_1)
366 		baud = min_t(int, baud, 1228800);
367 	else if (type == HX_CLONE)
368 		baud = min_t(int, baud, 115200);
369 	/* Direct (standard) baud rate encoding method */
370 	put_unaligned_le32(baud, buf);
371 
372 	return baud;
373 }
374 
375 static int pl2303_baudrate_encode_divisor(int baud, enum pl2303_type type,
376 								      u8 buf[4])
377 {
378 	/*
379 	 * Divisor based baud rate encoding method
380 	 *
381 	 * NOTE: HX clones do NOT support this method.
382 	 * It's not clear if the type_0/1 chips support it.
383 	 *
384 	 * divisor = 12MHz * 32 / baudrate = 2^A * B
385 	 *
386 	 * with
387 	 *
388 	 * A = buf[1] & 0x0e
389 	 * B = buf[0]  +  (buf[1] & 0x01) << 8
390 	 *
391 	 * Special cases:
392 	 * => 8 < B < 16: device seems to work not properly
393 	 * => B <= 8: device uses the max. value B = 512 instead
394 	 */
395 	unsigned int A, B;
396 
397 	/*
398 	 * NOTE: The Windows driver allows maximum baud rates of 110% of the
399 	 * specified maximium value.
400 	 * Quick tests with early (2004) HX (rev. A) chips suggest, that even
401 	 * higher baud rates (up to the maximum of 24M baud !) are working fine,
402 	 * but that should really be tested carefully in "real life" scenarios
403 	 * before removing the upper limit completely.
404 	 * Baud rates smaller than the specified 75 baud are definitely working
405 	 * fine.
406 	 */
407 	if (type == type_0 || type == type_1)
408 		baud = min_t(int, baud, 1228800 * 1.1);
409 	else if (type == HX_TA)
410 		baud = min_t(int, baud, 6000000 * 1.1);
411 	else if (type == HXD_EA_RA_SA)
412 		/* HXD, EA: 12Mbps; RA: 1Mbps; SA: 115200 bps */
413 		/*
414 		 * FIXME: as long as we don't know how to distinguish between
415 		 * these chip variants, allow the max. of these values
416 		 */
417 		baud = min_t(int, baud, 12000000 * 1.1);
418 	else if (type == TB)
419 		baud = min_t(int, baud, 12000000 * 1.1);
420 	/* Determine factors A and B */
421 	A = 0;
422 	B = 12000000 * 32 / baud;  /* 12MHz */
423 	B <<= 1; /* Add one bit for rounding */
424 	while (B > (512 << 1) && A <= 14) {
425 		A += 2;
426 		B >>= 2;
427 	}
428 	if (A > 14) { /* max. divisor = min. baudrate reached */
429 		A = 14;
430 		B = 512;
431 		/* => ~45.78 baud */
432 	} else {
433 		B = (B + 1) >> 1; /* Round the last bit */
434 	}
435 	/* Handle special cases */
436 	if (B == 512)
437 		B = 0; /* also: 1 to 8 */
438 	else if (B < 16)
439 		/*
440 		 * NOTE: With the current algorithm this happens
441 		 * only for A=0 and means that the min. divisor
442 		 * (respectively: the max. baudrate) is reached.
443 		 */
444 		B = 16;		/* => 24 MBaud */
445 	/* Encode the baud rate */
446 	buf[3] = 0x80;     /* Select divisor encoding method */
447 	buf[2] = 0;
448 	buf[1] = (A & 0x0e);		/* A */
449 	buf[1] |= ((B & 0x100) >> 8);	/* MSB of B */
450 	buf[0] = B & 0xff;		/* 8 LSBs of B */
451 	/* Calculate the actual/resulting baud rate */
452 	if (B <= 8)
453 		B = 512;
454 	baud = 12000000 * 32 / ((1 << A) * B);
455 
456 	return baud;
457 }
458 
459 static void pl2303_encode_baudrate(struct tty_struct *tty,
460 					struct usb_serial_port *port,
461 					enum pl2303_type type,
462 					u8 buf[4])
463 {
464 	int baud;
465 
466 	baud = tty_get_baud_rate(tty);
467 	dev_dbg(&port->dev, "baud requested = %d\n", baud);
468 	if (!baud)
469 		return;
470 	/*
471 	 * There are two methods for setting/encoding the baud rate
472 	 * 1) Direct method: encodes the baud rate value directly
473 	 *    => supported by all chip types
474 	 * 2) Divisor based method: encodes a divisor to a base value (12MHz*32)
475 	 *    => not supported by HX clones (and likely type_0/1 chips)
476 	 *
477 	 * NOTE: Although the divisor based baud rate encoding method is much
478 	 * more flexible, some of the standard baud rate values can not be
479 	 * realized exactly. But the difference is very small (max. 0.2%) and
480 	 * the device likely uses the same baud rate generator for both methods
481 	 * so that there is likley no difference.
482 	 */
483 	if (type == type_0 || type == type_1 || type == HX_CLONE)
484 		baud = pl2303_baudrate_encode_direct(baud, type, buf);
485 	else
486 		baud = pl2303_baudrate_encode_divisor(baud, type, buf);
487 	/* Save resulting baud rate */
488 	tty_encode_baud_rate(tty, baud, baud);
489 	dev_dbg(&port->dev, "baud set = %d\n", baud);
490 }
491 
492 static void pl2303_set_termios(struct tty_struct *tty,
493 		struct usb_serial_port *port, struct ktermios *old_termios)
494 {
495 	struct usb_serial *serial = port->serial;
496 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
497 	struct pl2303_private *priv = usb_get_serial_port_data(port);
498 	unsigned long flags;
499 	unsigned char *buf;
500 	int i;
501 	u8 control;
502 
503 	/*
504 	 * The PL2303 is reported to lose bytes if you change serial settings
505 	 * even to the same values as before. Thus we actually need to filter
506 	 * in this specific case.
507 	 */
508 	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
509 		return;
510 
511 	buf = kzalloc(7, GFP_KERNEL);
512 	if (!buf) {
513 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
514 		/* Report back no change occurred */
515 		if (old_termios)
516 			tty->termios = *old_termios;
517 		return;
518 	}
519 
520 	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
521 			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
522 			    0, 0, buf, 7, 100);
523 	dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %7ph\n", i, buf);
524 
525 	if (C_CSIZE(tty)) {
526 		switch (C_CSIZE(tty)) {
527 		case CS5:
528 			buf[6] = 5;
529 			break;
530 		case CS6:
531 			buf[6] = 6;
532 			break;
533 		case CS7:
534 			buf[6] = 7;
535 			break;
536 		default:
537 		case CS8:
538 			buf[6] = 8;
539 		}
540 		dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
541 	}
542 
543 	/* For reference:   buf[0]:buf[3] baud rate value */
544 	pl2303_encode_baudrate(tty, port, spriv->type, buf);
545 
546 	/* For reference buf[4]=0 is 1 stop bits */
547 	/* For reference buf[4]=1 is 1.5 stop bits */
548 	/* For reference buf[4]=2 is 2 stop bits */
549 	if (C_CSTOPB(tty)) {
550 		/*
551 		 * NOTE: Comply with "real" UARTs / RS232:
552 		 *       use 1.5 instead of 2 stop bits with 5 data bits
553 		 */
554 		if (C_CSIZE(tty) == CS5) {
555 			buf[4] = 1;
556 			dev_dbg(&port->dev, "stop bits = 1.5\n");
557 		} else {
558 			buf[4] = 2;
559 			dev_dbg(&port->dev, "stop bits = 2\n");
560 		}
561 	} else {
562 		buf[4] = 0;
563 		dev_dbg(&port->dev, "stop bits = 1\n");
564 	}
565 
566 	if (C_PARENB(tty)) {
567 		/* For reference buf[5]=0 is none parity */
568 		/* For reference buf[5]=1 is odd parity */
569 		/* For reference buf[5]=2 is even parity */
570 		/* For reference buf[5]=3 is mark parity */
571 		/* For reference buf[5]=4 is space parity */
572 		if (C_PARODD(tty)) {
573 			if (tty->termios.c_cflag & CMSPAR) {
574 				buf[5] = 3;
575 				dev_dbg(&port->dev, "parity = mark\n");
576 			} else {
577 				buf[5] = 1;
578 				dev_dbg(&port->dev, "parity = odd\n");
579 			}
580 		} else {
581 			if (tty->termios.c_cflag & CMSPAR) {
582 				buf[5] = 4;
583 				dev_dbg(&port->dev, "parity = space\n");
584 			} else {
585 				buf[5] = 2;
586 				dev_dbg(&port->dev, "parity = even\n");
587 			}
588 		}
589 	} else {
590 		buf[5] = 0;
591 		dev_dbg(&port->dev, "parity = none\n");
592 	}
593 
594 	i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
595 			    SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
596 			    0, 0, buf, 7, 100);
597 	dev_dbg(&port->dev, "0x21:0x20:0:0  %d\n", i);
598 
599 	/* change control lines if we are switching to or from B0 */
600 	spin_lock_irqsave(&priv->lock, flags);
601 	control = priv->line_control;
602 	if (C_BAUD(tty) == B0)
603 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
604 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
605 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
606 	if (control != priv->line_control) {
607 		control = priv->line_control;
608 		spin_unlock_irqrestore(&priv->lock, flags);
609 		pl2303_set_control_lines(port, control);
610 	} else {
611 		spin_unlock_irqrestore(&priv->lock, flags);
612 	}
613 
614 	memset(buf, 0, 7);
615 	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
616 			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
617 			    0, 0, buf, 7, 100);
618 	dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %7ph\n", i, buf);
619 
620 	if (C_CRTSCTS(tty)) {
621 		if (spriv->type == type_0 || spriv->type == type_1)
622 			pl2303_vendor_write(0x0, 0x41, serial);
623 		else
624 			pl2303_vendor_write(0x0, 0x61, serial);
625 	} else {
626 		pl2303_vendor_write(0x0, 0x0, serial);
627 	}
628 
629 	kfree(buf);
630 }
631 
632 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
633 {
634 	struct pl2303_private *priv = usb_get_serial_port_data(port);
635 	unsigned long flags;
636 	u8 control;
637 
638 	spin_lock_irqsave(&priv->lock, flags);
639 	/* Change DTR and RTS */
640 	if (on)
641 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
642 	else
643 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
644 	control = priv->line_control;
645 	spin_unlock_irqrestore(&priv->lock, flags);
646 	pl2303_set_control_lines(port, control);
647 }
648 
649 static void pl2303_close(struct usb_serial_port *port)
650 {
651 	usb_serial_generic_close(port);
652 	usb_kill_urb(port->interrupt_in_urb);
653 }
654 
655 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
656 {
657 	struct usb_serial *serial = port->serial;
658 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
659 	int result;
660 
661 	if (spriv->type == type_0 || spriv->type == type_1) {
662 		usb_clear_halt(serial->dev, port->write_urb->pipe);
663 		usb_clear_halt(serial->dev, port->read_urb->pipe);
664 	} else {
665 		/* reset upstream data pipes */
666 		pl2303_vendor_write(8, 0, serial);
667 		pl2303_vendor_write(9, 0, serial);
668 	}
669 
670 	/* Setup termios */
671 	if (tty)
672 		pl2303_set_termios(tty, port, NULL);
673 
674 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
675 	if (result) {
676 		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
677 			" error %d\n", __func__, result);
678 		return result;
679 	}
680 
681 	result = usb_serial_generic_open(tty, port);
682 	if (result) {
683 		usb_kill_urb(port->interrupt_in_urb);
684 		return result;
685 	}
686 
687 	return 0;
688 }
689 
690 static int pl2303_tiocmset(struct tty_struct *tty,
691 			   unsigned int set, unsigned int clear)
692 {
693 	struct usb_serial_port *port = tty->driver_data;
694 	struct pl2303_private *priv = usb_get_serial_port_data(port);
695 	unsigned long flags;
696 	u8 control;
697 	int ret;
698 
699 	spin_lock_irqsave(&priv->lock, flags);
700 	if (set & TIOCM_RTS)
701 		priv->line_control |= CONTROL_RTS;
702 	if (set & TIOCM_DTR)
703 		priv->line_control |= CONTROL_DTR;
704 	if (clear & TIOCM_RTS)
705 		priv->line_control &= ~CONTROL_RTS;
706 	if (clear & TIOCM_DTR)
707 		priv->line_control &= ~CONTROL_DTR;
708 	control = priv->line_control;
709 	spin_unlock_irqrestore(&priv->lock, flags);
710 
711 	ret = pl2303_set_control_lines(port, control);
712 	if (ret)
713 		return usb_translate_errors(ret);
714 
715 	return 0;
716 }
717 
718 static int pl2303_tiocmget(struct tty_struct *tty)
719 {
720 	struct usb_serial_port *port = tty->driver_data;
721 	struct pl2303_private *priv = usb_get_serial_port_data(port);
722 	unsigned long flags;
723 	unsigned int mcr;
724 	unsigned int status;
725 	unsigned int result;
726 
727 	spin_lock_irqsave(&priv->lock, flags);
728 	mcr = priv->line_control;
729 	status = priv->line_status;
730 	spin_unlock_irqrestore(&priv->lock, flags);
731 
732 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
733 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
734 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
735 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
736 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
737 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
738 
739 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
740 
741 	return result;
742 }
743 
744 static int pl2303_carrier_raised(struct usb_serial_port *port)
745 {
746 	struct pl2303_private *priv = usb_get_serial_port_data(port);
747 	if (priv->line_status & UART_DCD)
748 		return 1;
749 	return 0;
750 }
751 
752 static int pl2303_tiocmiwait(struct tty_struct *tty, unsigned long arg)
753 {
754 	struct usb_serial_port *port = tty->driver_data;
755 	struct pl2303_private *priv = usb_get_serial_port_data(port);
756 	unsigned long flags;
757 	unsigned int prevstatus;
758 	unsigned int status;
759 	unsigned int changed;
760 
761 	spin_lock_irqsave(&priv->lock, flags);
762 	prevstatus = priv->line_status;
763 	spin_unlock_irqrestore(&priv->lock, flags);
764 
765 	while (1) {
766 		interruptible_sleep_on(&port->port.delta_msr_wait);
767 		/* see if a signal did it */
768 		if (signal_pending(current))
769 			return -ERESTARTSYS;
770 
771 		if (port->serial->disconnected)
772 			return -EIO;
773 
774 		spin_lock_irqsave(&priv->lock, flags);
775 		status = priv->line_status;
776 		spin_unlock_irqrestore(&priv->lock, flags);
777 
778 		changed = prevstatus ^ status;
779 
780 		if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
781 		    ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
782 		    ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
783 		    ((arg & TIOCM_CTS) && (changed & UART_CTS))) {
784 			return 0;
785 		}
786 		prevstatus = status;
787 	}
788 	/* NOTREACHED */
789 	return 0;
790 }
791 
792 static int pl2303_ioctl(struct tty_struct *tty,
793 			unsigned int cmd, unsigned long arg)
794 {
795 	struct serial_struct ser;
796 	struct usb_serial_port *port = tty->driver_data;
797 
798 	dev_dbg(&port->dev, "%s cmd = 0x%04x\n", __func__, cmd);
799 
800 	switch (cmd) {
801 	case TIOCGSERIAL:
802 		memset(&ser, 0, sizeof ser);
803 		ser.type = PORT_16654;
804 		ser.line = port->minor;
805 		ser.port = port->port_number;
806 		ser.baud_base = 460800;
807 
808 		if (copy_to_user((void __user *)arg, &ser, sizeof ser))
809 			return -EFAULT;
810 
811 		return 0;
812 	default:
813 		dev_dbg(&port->dev, "%s not supported = 0x%04x\n", __func__, cmd);
814 		break;
815 	}
816 	return -ENOIOCTLCMD;
817 }
818 
819 static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
820 {
821 	struct usb_serial_port *port = tty->driver_data;
822 	struct usb_serial *serial = port->serial;
823 	u16 state;
824 	int result;
825 
826 	if (break_state == 0)
827 		state = BREAK_OFF;
828 	else
829 		state = BREAK_ON;
830 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
831 			state == BREAK_OFF ? "off" : "on");
832 
833 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
834 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
835 				 0, NULL, 0, 100);
836 	/* NOTE: HX clones don't support sending breaks, -EPIPE is returned */
837 	if (result)
838 		dev_err(&port->dev, "error sending break = %d\n", result);
839 }
840 
841 static void pl2303_update_line_status(struct usb_serial_port *port,
842 				      unsigned char *data,
843 				      unsigned int actual_length)
844 {
845 
846 	struct pl2303_private *priv = usb_get_serial_port_data(port);
847 	struct tty_struct *tty;
848 	unsigned long flags;
849 	u8 status_idx = UART_STATE;
850 	u8 length = UART_STATE + 1;
851 	u8 prev_line_status;
852 	u16 idv, idp;
853 
854 	idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
855 	idp = le16_to_cpu(port->serial->dev->descriptor.idProduct);
856 
857 
858 	if (idv == SIEMENS_VENDOR_ID) {
859 		if (idp == SIEMENS_PRODUCT_ID_X65 ||
860 		    idp == SIEMENS_PRODUCT_ID_SX1 ||
861 		    idp == SIEMENS_PRODUCT_ID_X75) {
862 
863 			length = 1;
864 			status_idx = 0;
865 		}
866 	}
867 
868 	if (actual_length < length)
869 		return;
870 
871 	/* Save off the uart status for others to look at */
872 	spin_lock_irqsave(&priv->lock, flags);
873 	prev_line_status = priv->line_status;
874 	priv->line_status = data[status_idx];
875 	spin_unlock_irqrestore(&priv->lock, flags);
876 	if (priv->line_status & UART_BREAK_ERROR)
877 		usb_serial_handle_break(port);
878 	wake_up_interruptible(&port->port.delta_msr_wait);
879 
880 	tty = tty_port_tty_get(&port->port);
881 	if (!tty)
882 		return;
883 	if ((priv->line_status ^ prev_line_status) & UART_DCD)
884 		usb_serial_handle_dcd_change(port, tty,
885 				priv->line_status & UART_DCD);
886 	tty_kref_put(tty);
887 }
888 
889 static void pl2303_read_int_callback(struct urb *urb)
890 {
891 	struct usb_serial_port *port =  urb->context;
892 	unsigned char *data = urb->transfer_buffer;
893 	unsigned int actual_length = urb->actual_length;
894 	int status = urb->status;
895 	int retval;
896 
897 	switch (status) {
898 	case 0:
899 		/* success */
900 		break;
901 	case -ECONNRESET:
902 	case -ENOENT:
903 	case -ESHUTDOWN:
904 		/* this urb is terminated, clean up */
905 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
906 			__func__, status);
907 		return;
908 	default:
909 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
910 			__func__, status);
911 		goto exit;
912 	}
913 
914 	usb_serial_debug_data(&port->dev, __func__,
915 			      urb->actual_length, urb->transfer_buffer);
916 
917 	pl2303_update_line_status(port, data, actual_length);
918 
919 exit:
920 	retval = usb_submit_urb(urb, GFP_ATOMIC);
921 	if (retval)
922 		dev_err(&port->dev,
923 			"%s - usb_submit_urb failed with result %d\n",
924 			__func__, retval);
925 }
926 
927 static void pl2303_process_read_urb(struct urb *urb)
928 {
929 	struct usb_serial_port *port = urb->context;
930 	struct pl2303_private *priv = usb_get_serial_port_data(port);
931 	unsigned char *data = urb->transfer_buffer;
932 	char tty_flag = TTY_NORMAL;
933 	unsigned long flags;
934 	u8 line_status;
935 	int i;
936 
937 	/* update line status */
938 	spin_lock_irqsave(&priv->lock, flags);
939 	line_status = priv->line_status;
940 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
941 	spin_unlock_irqrestore(&priv->lock, flags);
942 	wake_up_interruptible(&port->port.delta_msr_wait);
943 
944 	if (!urb->actual_length)
945 		return;
946 
947 	/* break takes precedence over parity, */
948 	/* which takes precedence over framing errors */
949 	if (line_status & UART_BREAK_ERROR)
950 		tty_flag = TTY_BREAK;
951 	else if (line_status & UART_PARITY_ERROR)
952 		tty_flag = TTY_PARITY;
953 	else if (line_status & UART_FRAME_ERROR)
954 		tty_flag = TTY_FRAME;
955 
956 	if (tty_flag != TTY_NORMAL)
957 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
958 								tty_flag);
959 	/* overrun is special, not associated with a char */
960 	if (line_status & UART_OVERRUN_ERROR)
961 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
962 
963 	if (port->port.console && port->sysrq) {
964 		for (i = 0; i < urb->actual_length; ++i)
965 			if (!usb_serial_handle_sysrq_char(port, data[i]))
966 				tty_insert_flip_char(&port->port, data[i],
967 						tty_flag);
968 	} else {
969 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
970 							urb->actual_length);
971 	}
972 
973 	tty_flip_buffer_push(&port->port);
974 }
975 
976 /* All of the device info needed for the PL2303 SIO serial converter */
977 static struct usb_serial_driver pl2303_device = {
978 	.driver = {
979 		.owner =	THIS_MODULE,
980 		.name =		"pl2303",
981 	},
982 	.id_table =		id_table,
983 	.num_ports =		1,
984 	.bulk_in_size =		256,
985 	.bulk_out_size =	256,
986 	.open =			pl2303_open,
987 	.close =		pl2303_close,
988 	.dtr_rts = 		pl2303_dtr_rts,
989 	.carrier_raised =	pl2303_carrier_raised,
990 	.ioctl =		pl2303_ioctl,
991 	.break_ctl =		pl2303_break_ctl,
992 	.set_termios =		pl2303_set_termios,
993 	.tiocmget =		pl2303_tiocmget,
994 	.tiocmset =		pl2303_tiocmset,
995 	.tiocmiwait =		pl2303_tiocmiwait,
996 	.process_read_urb =	pl2303_process_read_urb,
997 	.read_int_callback =	pl2303_read_int_callback,
998 	.attach =		pl2303_startup,
999 	.release =		pl2303_release,
1000 	.port_probe =		pl2303_port_probe,
1001 	.port_remove =		pl2303_port_remove,
1002 };
1003 
1004 static struct usb_serial_driver * const serial_drivers[] = {
1005 	&pl2303_device, NULL
1006 };
1007 
1008 module_usb_serial_driver(serial_drivers, id_table);
1009 
1010 MODULE_DESCRIPTION(DRIVER_DESC);
1011 MODULE_LICENSE("GPL");
1012