xref: /openbmc/linux/drivers/usb/serial/pl2303.c (revision 6197e5b7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Prolific PL2303 USB to serial adaptor driver
4  *
5  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2003 IBM Corp.
7  *
8  * Original driver for 2.2.x by anonymous
9  *
10  * See Documentation/usb/usb-serial.rst for more information on using this
11  * driver
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_driver.h>
19 #include <linux/tty_flip.h>
20 #include <linux/serial.h>
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/spinlock.h>
24 #include <linux/uaccess.h>
25 #include <linux/usb.h>
26 #include <linux/usb/serial.h>
27 #include <asm/unaligned.h>
28 #include "pl2303.h"
29 
30 
31 #define PL2303_QUIRK_UART_STATE_IDX0		BIT(0)
32 #define PL2303_QUIRK_LEGACY			BIT(1)
33 #define PL2303_QUIRK_ENDPOINT_HACK		BIT(2)
34 
35 static const struct usb_device_id id_table[] = {
36 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID),
37 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
38 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
39 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
40 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
41 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_CHILITAG) },
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(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ZTEK) },
49 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_TB) },
50 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GC) },
51 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GB) },
52 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GT) },
53 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GL) },
54 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GE) },
55 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GS) },
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 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
60 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC485),
61 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
62 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC232B),
63 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
64 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID2) },
65 	{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
66 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
67 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
68 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
69 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
70 	{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
71 	{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
72 	{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
73 	{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
74 	{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
75 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
76 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
77 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
78 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
79 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
80 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
81 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
82 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
83 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81),
84 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
85 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
86 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
87 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
88 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
89 	{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
90 	{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
91 	{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
92 	{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
93 	{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
94 	{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID),
95 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
96 	{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
97 	{ USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
98 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
99 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
100 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
101 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220TA_PRODUCT_ID) },
102 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD381_PRODUCT_ID) },
103 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD381GC_PRODUCT_ID) },
104 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD960_PRODUCT_ID) },
105 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD960TA_PRODUCT_ID) },
106 	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
107 	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
108 	{ USB_DEVICE(HP_VENDOR_ID, HP_LM920_PRODUCT_ID) },
109 	{ USB_DEVICE(HP_VENDOR_ID, HP_LM940_PRODUCT_ID) },
110 	{ USB_DEVICE(HP_VENDOR_ID, HP_TD620_PRODUCT_ID) },
111 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
112 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
113 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
114 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
115 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
116 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
117 	{ USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
118 	{ }					/* Terminating entry */
119 };
120 
121 MODULE_DEVICE_TABLE(usb, id_table);
122 
123 #define SET_LINE_REQUEST_TYPE		0x21
124 #define SET_LINE_REQUEST		0x20
125 
126 #define SET_CONTROL_REQUEST_TYPE	0x21
127 #define SET_CONTROL_REQUEST		0x22
128 #define CONTROL_DTR			0x01
129 #define CONTROL_RTS			0x02
130 
131 #define BREAK_REQUEST_TYPE		0x21
132 #define BREAK_REQUEST			0x23
133 #define BREAK_ON			0xffff
134 #define BREAK_OFF			0x0000
135 
136 #define GET_LINE_REQUEST_TYPE		0xa1
137 #define GET_LINE_REQUEST		0x21
138 
139 #define VENDOR_WRITE_REQUEST_TYPE	0x40
140 #define VENDOR_WRITE_REQUEST		0x01
141 #define VENDOR_WRITE_NREQUEST		0x80
142 
143 #define VENDOR_READ_REQUEST_TYPE	0xc0
144 #define VENDOR_READ_REQUEST		0x01
145 #define VENDOR_READ_NREQUEST		0x81
146 
147 #define UART_STATE_INDEX		8
148 #define UART_STATE_MSR_MASK		0x8b
149 #define UART_STATE_TRANSIENT_MASK	0x74
150 #define UART_DCD			0x01
151 #define UART_DSR			0x02
152 #define UART_BREAK_ERROR		0x04
153 #define UART_RING			0x08
154 #define UART_FRAME_ERROR		0x10
155 #define UART_PARITY_ERROR		0x20
156 #define UART_OVERRUN_ERROR		0x40
157 #define UART_CTS			0x80
158 
159 #define PL2303_FLOWCTRL_MASK		0xf0
160 
161 #define PL2303_READ_TYPE_HX_STATUS	0x8080
162 
163 #define PL2303_HXN_RESET_REG		0x07
164 #define PL2303_HXN_RESET_UPSTREAM_PIPE	0x02
165 #define PL2303_HXN_RESET_DOWNSTREAM_PIPE	0x01
166 
167 #define PL2303_HXN_FLOWCTRL_REG		0x0a
168 #define PL2303_HXN_FLOWCTRL_MASK	0x1c
169 #define PL2303_HXN_FLOWCTRL_NONE	0x1c
170 #define PL2303_HXN_FLOWCTRL_RTS_CTS	0x18
171 #define PL2303_HXN_FLOWCTRL_XON_XOFF	0x0c
172 
173 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
174 
175 enum pl2303_type {
176 	TYPE_01,	/* Type 0 and 1 (difference unknown) */
177 	TYPE_HX,	/* HX version of the pl2303 chip */
178 	TYPE_HXN,	/* HXN version of the pl2303 chip */
179 	TYPE_COUNT
180 };
181 
182 struct pl2303_type_data {
183 	speed_t max_baud_rate;
184 	unsigned long quirks;
185 	unsigned int no_autoxonxoff:1;
186 	unsigned int no_divisors:1;
187 };
188 
189 struct pl2303_serial_private {
190 	const struct pl2303_type_data *type;
191 	unsigned long quirks;
192 };
193 
194 struct pl2303_private {
195 	spinlock_t lock;
196 	u8 line_control;
197 	u8 line_status;
198 
199 	u8 line_settings[7];
200 };
201 
202 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
203 	[TYPE_01] = {
204 		.max_baud_rate		= 1228800,
205 		.quirks			= PL2303_QUIRK_LEGACY,
206 		.no_autoxonxoff		= true,
207 	},
208 	[TYPE_HX] = {
209 		.max_baud_rate		= 12000000,
210 	},
211 	[TYPE_HXN] = {
212 		.max_baud_rate		= 12000000,
213 		.no_divisors		= true,
214 	},
215 };
216 
217 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
218 							unsigned char buf[1])
219 {
220 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
221 	struct device *dev = &serial->interface->dev;
222 	u8 request;
223 	int res;
224 
225 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
226 		request = VENDOR_READ_NREQUEST;
227 	else
228 		request = VENDOR_READ_REQUEST;
229 
230 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
231 			request, VENDOR_READ_REQUEST_TYPE,
232 			value, 0, buf, 1, 100);
233 	if (res != 1) {
234 		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
235 								value, res);
236 		if (res >= 0)
237 			res = -EIO;
238 
239 		return res;
240 	}
241 
242 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
243 
244 	return 0;
245 }
246 
247 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
248 {
249 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
250 	struct device *dev = &serial->interface->dev;
251 	u8 request;
252 	int res;
253 
254 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
255 
256 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
257 		request = VENDOR_WRITE_NREQUEST;
258 	else
259 		request = VENDOR_WRITE_REQUEST;
260 
261 	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
262 			request, VENDOR_WRITE_REQUEST_TYPE,
263 			value, index, NULL, 0, 100);
264 	if (res) {
265 		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
266 								value, res);
267 		return res;
268 	}
269 
270 	return 0;
271 }
272 
273 static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
274 {
275 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
276 	int ret = 0;
277 	u8 *buf;
278 
279 	buf = kmalloc(1, GFP_KERNEL);
280 	if (!buf)
281 		return -ENOMEM;
282 
283 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
284 		ret = pl2303_vendor_read(serial, reg, buf);
285 	else
286 		ret = pl2303_vendor_read(serial, reg | 0x80, buf);
287 
288 	if (ret)
289 		goto out_free;
290 
291 	*buf &= ~mask;
292 	*buf |= val & mask;
293 
294 	ret = pl2303_vendor_write(serial, reg, *buf);
295 out_free:
296 	kfree(buf);
297 
298 	return ret;
299 }
300 
301 static int pl2303_probe(struct usb_serial *serial,
302 					const struct usb_device_id *id)
303 {
304 	usb_set_serial_data(serial, (void *)id->driver_info);
305 
306 	return 0;
307 }
308 
309 /*
310  * Use interrupt endpoint from first interface if available.
311  *
312  * This is needed due to the looney way its endpoints are set up.
313  */
314 static int pl2303_endpoint_hack(struct usb_serial *serial,
315 					struct usb_serial_endpoints *epds)
316 {
317 	struct usb_interface *interface = serial->interface;
318 	struct usb_device *dev = serial->dev;
319 	struct device *ddev = &interface->dev;
320 	struct usb_host_interface *iface_desc;
321 	struct usb_endpoint_descriptor *endpoint;
322 	unsigned int i;
323 
324 	if (interface == dev->actconfig->interface[0])
325 		return 0;
326 
327 	/* check out the endpoints of the other interface */
328 	iface_desc = dev->actconfig->interface[0]->cur_altsetting;
329 
330 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
331 		endpoint = &iface_desc->endpoint[i].desc;
332 
333 		if (!usb_endpoint_is_int_in(endpoint))
334 			continue;
335 
336 		dev_dbg(ddev, "found interrupt in on separate interface\n");
337 		if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
338 			epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
339 	}
340 
341 	return 0;
342 }
343 
344 static int pl2303_calc_num_ports(struct usb_serial *serial,
345 					struct usb_serial_endpoints *epds)
346 {
347 	unsigned long quirks = (unsigned long)usb_get_serial_data(serial);
348 	struct device *dev = &serial->interface->dev;
349 	int ret;
350 
351 	if (quirks & PL2303_QUIRK_ENDPOINT_HACK) {
352 		ret = pl2303_endpoint_hack(serial, epds);
353 		if (ret)
354 			return ret;
355 	}
356 
357 	if (epds->num_interrupt_in < 1) {
358 		dev_err(dev, "required interrupt-in endpoint missing\n");
359 		return -ENODEV;
360 	}
361 
362 	return 1;
363 }
364 
365 static int pl2303_startup(struct usb_serial *serial)
366 {
367 	struct pl2303_serial_private *spriv;
368 	enum pl2303_type type = TYPE_01;
369 	unsigned char *buf;
370 	int res;
371 
372 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
373 	if (!spriv)
374 		return -ENOMEM;
375 
376 	buf = kmalloc(1, GFP_KERNEL);
377 	if (!buf) {
378 		kfree(spriv);
379 		return -ENOMEM;
380 	}
381 
382 	if (serial->dev->descriptor.bDeviceClass == 0x02)
383 		type = TYPE_01;		/* type 0 */
384 	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
385 		type = TYPE_HX;
386 	else if (serial->dev->descriptor.bDeviceClass == 0x00)
387 		type = TYPE_01;		/* type 1 */
388 	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
389 		type = TYPE_01;		/* type 1 */
390 	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
391 
392 	if (type == TYPE_HX) {
393 		res = usb_control_msg(serial->dev,
394 				usb_rcvctrlpipe(serial->dev, 0),
395 				VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
396 				PL2303_READ_TYPE_HX_STATUS, 0, buf, 1, 100);
397 		if (res != 1)
398 			type = TYPE_HXN;
399 	}
400 
401 	spriv->type = &pl2303_type_data[type];
402 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
403 	spriv->quirks |= spriv->type->quirks;
404 
405 	usb_set_serial_data(serial, spriv);
406 
407 	if (type != TYPE_HXN) {
408 		pl2303_vendor_read(serial, 0x8484, buf);
409 		pl2303_vendor_write(serial, 0x0404, 0);
410 		pl2303_vendor_read(serial, 0x8484, buf);
411 		pl2303_vendor_read(serial, 0x8383, buf);
412 		pl2303_vendor_read(serial, 0x8484, buf);
413 		pl2303_vendor_write(serial, 0x0404, 1);
414 		pl2303_vendor_read(serial, 0x8484, buf);
415 		pl2303_vendor_read(serial, 0x8383, buf);
416 		pl2303_vendor_write(serial, 0, 1);
417 		pl2303_vendor_write(serial, 1, 0);
418 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
419 			pl2303_vendor_write(serial, 2, 0x24);
420 		else
421 			pl2303_vendor_write(serial, 2, 0x44);
422 	}
423 
424 	kfree(buf);
425 
426 	return 0;
427 }
428 
429 static void pl2303_release(struct usb_serial *serial)
430 {
431 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
432 
433 	kfree(spriv);
434 }
435 
436 static int pl2303_port_probe(struct usb_serial_port *port)
437 {
438 	struct pl2303_private *priv;
439 
440 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
441 	if (!priv)
442 		return -ENOMEM;
443 
444 	spin_lock_init(&priv->lock);
445 
446 	usb_set_serial_port_data(port, priv);
447 
448 	port->port.drain_delay = 256;
449 
450 	return 0;
451 }
452 
453 static void pl2303_port_remove(struct usb_serial_port *port)
454 {
455 	struct pl2303_private *priv = usb_get_serial_port_data(port);
456 
457 	kfree(priv);
458 }
459 
460 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
461 {
462 	struct usb_device *dev = port->serial->dev;
463 	int retval;
464 
465 	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
466 
467 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
468 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
469 				 value, 0, NULL, 0, 100);
470 	if (retval)
471 		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
472 
473 	return retval;
474 }
475 
476 /*
477  * Returns the nearest supported baud rate that can be set directly without
478  * using divisors.
479  */
480 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
481 {
482 	static const speed_t baud_sup[] = {
483 		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
484 		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
485 		614400, 921600, 1228800, 2457600, 3000000, 6000000
486 	};
487 
488 	unsigned i;
489 
490 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
491 		if (baud_sup[i] > baud)
492 			break;
493 	}
494 
495 	if (i == ARRAY_SIZE(baud_sup))
496 		baud = baud_sup[i - 1];
497 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
498 		baud = baud_sup[i - 1];
499 	else
500 		baud = baud_sup[i];
501 
502 	return baud;
503 }
504 
505 /*
506  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
507  *       use 9600 baud.
508  */
509 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
510 								speed_t baud)
511 {
512 	put_unaligned_le32(baud, buf);
513 
514 	return baud;
515 }
516 
517 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
518 								speed_t baud)
519 {
520 	unsigned int baseline, mantissa, exponent;
521 
522 	/*
523 	 * Apparently the formula is:
524 	 *   baudrate = 12M * 32 / (mantissa * 4^exponent)
525 	 * where
526 	 *   mantissa = buf[8:0]
527 	 *   exponent = buf[11:9]
528 	 */
529 	baseline = 12000000 * 32;
530 	mantissa = baseline / baud;
531 	if (mantissa == 0)
532 		mantissa = 1;	/* Avoid dividing by zero if baud > 32*12M. */
533 	exponent = 0;
534 	while (mantissa >= 512) {
535 		if (exponent < 7) {
536 			mantissa >>= 2;	/* divide by 4 */
537 			exponent++;
538 		} else {
539 			/* Exponent is maxed. Trim mantissa and leave. */
540 			mantissa = 511;
541 			break;
542 		}
543 	}
544 
545 	buf[3] = 0x80;
546 	buf[2] = 0;
547 	buf[1] = exponent << 1 | mantissa >> 8;
548 	buf[0] = mantissa & 0xff;
549 
550 	/* Calculate and return the exact baud rate. */
551 	baud = (baseline / mantissa) >> (exponent << 1);
552 
553 	return baud;
554 }
555 
556 static void pl2303_encode_baud_rate(struct tty_struct *tty,
557 					struct usb_serial_port *port,
558 					u8 buf[4])
559 {
560 	struct usb_serial *serial = port->serial;
561 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
562 	speed_t	baud_sup;
563 	speed_t baud;
564 
565 	baud = tty_get_baud_rate(tty);
566 	dev_dbg(&port->dev, "baud requested = %u\n", baud);
567 	if (!baud)
568 		return;
569 
570 	if (spriv->type->max_baud_rate)
571 		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
572 	/*
573 	 * Use direct method for supported baud rates, otherwise use divisors.
574 	 * Newer chip types do not support divisor encoding.
575 	 */
576 	if (spriv->type->no_divisors)
577 		baud_sup = baud;
578 	else
579 		baud_sup = pl2303_get_supported_baud_rate(baud);
580 
581 	if (baud == baud_sup)
582 		baud = pl2303_encode_baud_rate_direct(buf, baud);
583 	else
584 		baud = pl2303_encode_baud_rate_divisor(buf, baud);
585 
586 	/* Save resulting baud rate */
587 	tty_encode_baud_rate(tty, baud, baud);
588 	dev_dbg(&port->dev, "baud set = %u\n", baud);
589 }
590 
591 static int pl2303_get_line_request(struct usb_serial_port *port,
592 							unsigned char buf[7])
593 {
594 	struct usb_device *udev = port->serial->dev;
595 	int ret;
596 
597 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
598 				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
599 				0, 0, buf, 7, 100);
600 	if (ret != 7) {
601 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
602 
603 		if (ret >= 0)
604 			ret = -EIO;
605 
606 		return ret;
607 	}
608 
609 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
610 
611 	return 0;
612 }
613 
614 static int pl2303_set_line_request(struct usb_serial_port *port,
615 							unsigned char buf[7])
616 {
617 	struct usb_device *udev = port->serial->dev;
618 	int ret;
619 
620 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
621 				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
622 				0, 0, buf, 7, 100);
623 	if (ret < 0) {
624 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
625 		return ret;
626 	}
627 
628 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
629 
630 	return 0;
631 }
632 
633 static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
634 {
635 	bool ixon_change;
636 
637 	ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
638 			a->c_cc[VSTART] != b->c_cc[VSTART] ||
639 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
640 
641 	return tty_termios_hw_change(a, b) || ixon_change;
642 }
643 
644 static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
645 {
646 	if (!I_IXON(tty) || I_IXANY(tty))
647 		return false;
648 
649 	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
650 		return false;
651 
652 	if (type->no_autoxonxoff)
653 		return false;
654 
655 	return true;
656 }
657 
658 static void pl2303_set_termios(struct tty_struct *tty,
659 		struct usb_serial_port *port, struct ktermios *old_termios)
660 {
661 	struct usb_serial *serial = port->serial;
662 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
663 	struct pl2303_private *priv = usb_get_serial_port_data(port);
664 	unsigned long flags;
665 	unsigned char *buf;
666 	int ret;
667 	u8 control;
668 
669 	if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
670 		return;
671 
672 	buf = kzalloc(7, GFP_KERNEL);
673 	if (!buf) {
674 		/* Report back no change occurred */
675 		if (old_termios)
676 			tty->termios = *old_termios;
677 		return;
678 	}
679 
680 	pl2303_get_line_request(port, buf);
681 
682 	switch (C_CSIZE(tty)) {
683 	case CS5:
684 		buf[6] = 5;
685 		break;
686 	case CS6:
687 		buf[6] = 6;
688 		break;
689 	case CS7:
690 		buf[6] = 7;
691 		break;
692 	default:
693 	case CS8:
694 		buf[6] = 8;
695 	}
696 	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
697 
698 	/* For reference buf[0]:buf[3] baud rate value */
699 	pl2303_encode_baud_rate(tty, port, &buf[0]);
700 
701 	/* For reference buf[4]=0 is 1 stop bits */
702 	/* For reference buf[4]=1 is 1.5 stop bits */
703 	/* For reference buf[4]=2 is 2 stop bits */
704 	if (C_CSTOPB(tty)) {
705 		/*
706 		 * NOTE: Comply with "real" UARTs / RS232:
707 		 *       use 1.5 instead of 2 stop bits with 5 data bits
708 		 */
709 		if (C_CSIZE(tty) == CS5) {
710 			buf[4] = 1;
711 			dev_dbg(&port->dev, "stop bits = 1.5\n");
712 		} else {
713 			buf[4] = 2;
714 			dev_dbg(&port->dev, "stop bits = 2\n");
715 		}
716 	} else {
717 		buf[4] = 0;
718 		dev_dbg(&port->dev, "stop bits = 1\n");
719 	}
720 
721 	if (C_PARENB(tty)) {
722 		/* For reference buf[5]=0 is none parity */
723 		/* For reference buf[5]=1 is odd parity */
724 		/* For reference buf[5]=2 is even parity */
725 		/* For reference buf[5]=3 is mark parity */
726 		/* For reference buf[5]=4 is space parity */
727 		if (C_PARODD(tty)) {
728 			if (C_CMSPAR(tty)) {
729 				buf[5] = 3;
730 				dev_dbg(&port->dev, "parity = mark\n");
731 			} else {
732 				buf[5] = 1;
733 				dev_dbg(&port->dev, "parity = odd\n");
734 			}
735 		} else {
736 			if (C_CMSPAR(tty)) {
737 				buf[5] = 4;
738 				dev_dbg(&port->dev, "parity = space\n");
739 			} else {
740 				buf[5] = 2;
741 				dev_dbg(&port->dev, "parity = even\n");
742 			}
743 		}
744 	} else {
745 		buf[5] = 0;
746 		dev_dbg(&port->dev, "parity = none\n");
747 	}
748 
749 	/*
750 	 * Some PL2303 are known to lose bytes if you change serial settings
751 	 * even to the same values as before. Thus we actually need to filter
752 	 * in this specific case.
753 	 *
754 	 * Note that the tty_termios_hw_change check above is not sufficient
755 	 * as a previously requested baud rate may differ from the one
756 	 * actually used (and stored in old_termios).
757 	 *
758 	 * NOTE: No additional locking needed for line_settings as it is
759 	 *       only used in set_termios, which is serialised against itself.
760 	 */
761 	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
762 		ret = pl2303_set_line_request(port, buf);
763 		if (!ret)
764 			memcpy(priv->line_settings, buf, 7);
765 	}
766 
767 	/* change control lines if we are switching to or from B0 */
768 	spin_lock_irqsave(&priv->lock, flags);
769 	control = priv->line_control;
770 	if (C_BAUD(tty) == B0)
771 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
772 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
773 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
774 	if (control != priv->line_control) {
775 		control = priv->line_control;
776 		spin_unlock_irqrestore(&priv->lock, flags);
777 		pl2303_set_control_lines(port, control);
778 	} else {
779 		spin_unlock_irqrestore(&priv->lock, flags);
780 	}
781 
782 	if (C_CRTSCTS(tty)) {
783 		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
784 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
785 		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
786 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
787 					PL2303_HXN_FLOWCTRL_MASK,
788 					PL2303_HXN_FLOWCTRL_RTS_CTS);
789 		} else {
790 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
791 		}
792 	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
793 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
794 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
795 					PL2303_HXN_FLOWCTRL_MASK,
796 					PL2303_HXN_FLOWCTRL_XON_XOFF);
797 		} else {
798 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
799 		}
800 	} else {
801 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
802 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
803 					PL2303_HXN_FLOWCTRL_MASK,
804 					PL2303_HXN_FLOWCTRL_NONE);
805 		} else {
806 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
807 		}
808 	}
809 
810 	kfree(buf);
811 }
812 
813 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
814 {
815 	struct pl2303_private *priv = usb_get_serial_port_data(port);
816 	unsigned long flags;
817 	u8 control;
818 
819 	spin_lock_irqsave(&priv->lock, flags);
820 	if (on)
821 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
822 	else
823 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
824 	control = priv->line_control;
825 	spin_unlock_irqrestore(&priv->lock, flags);
826 
827 	pl2303_set_control_lines(port, control);
828 }
829 
830 static void pl2303_close(struct usb_serial_port *port)
831 {
832 	usb_serial_generic_close(port);
833 	usb_kill_urb(port->interrupt_in_urb);
834 	pl2303_set_break(port, false);
835 }
836 
837 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
838 {
839 	struct usb_serial *serial = port->serial;
840 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
841 	int result;
842 
843 	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
844 		usb_clear_halt(serial->dev, port->write_urb->pipe);
845 		usb_clear_halt(serial->dev, port->read_urb->pipe);
846 	} else {
847 		/* reset upstream data pipes */
848 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
849 			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
850 					PL2303_HXN_RESET_UPSTREAM_PIPE |
851 					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
852 		} else {
853 			pl2303_vendor_write(serial, 8, 0);
854 			pl2303_vendor_write(serial, 9, 0);
855 		}
856 	}
857 
858 	/* Setup termios */
859 	if (tty)
860 		pl2303_set_termios(tty, port, NULL);
861 
862 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
863 	if (result) {
864 		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
865 			result);
866 		return result;
867 	}
868 
869 	result = usb_serial_generic_open(tty, port);
870 	if (result) {
871 		usb_kill_urb(port->interrupt_in_urb);
872 		return result;
873 	}
874 
875 	return 0;
876 }
877 
878 static int pl2303_tiocmset(struct tty_struct *tty,
879 			   unsigned int set, unsigned int clear)
880 {
881 	struct usb_serial_port *port = tty->driver_data;
882 	struct pl2303_private *priv = usb_get_serial_port_data(port);
883 	unsigned long flags;
884 	u8 control;
885 	int ret;
886 
887 	spin_lock_irqsave(&priv->lock, flags);
888 	if (set & TIOCM_RTS)
889 		priv->line_control |= CONTROL_RTS;
890 	if (set & TIOCM_DTR)
891 		priv->line_control |= CONTROL_DTR;
892 	if (clear & TIOCM_RTS)
893 		priv->line_control &= ~CONTROL_RTS;
894 	if (clear & TIOCM_DTR)
895 		priv->line_control &= ~CONTROL_DTR;
896 	control = priv->line_control;
897 	spin_unlock_irqrestore(&priv->lock, flags);
898 
899 	ret = pl2303_set_control_lines(port, control);
900 	if (ret)
901 		return usb_translate_errors(ret);
902 
903 	return 0;
904 }
905 
906 static int pl2303_tiocmget(struct tty_struct *tty)
907 {
908 	struct usb_serial_port *port = tty->driver_data;
909 	struct pl2303_private *priv = usb_get_serial_port_data(port);
910 	unsigned long flags;
911 	unsigned int mcr;
912 	unsigned int status;
913 	unsigned int result;
914 
915 	spin_lock_irqsave(&priv->lock, flags);
916 	mcr = priv->line_control;
917 	status = priv->line_status;
918 	spin_unlock_irqrestore(&priv->lock, flags);
919 
920 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
921 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
922 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
923 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
924 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
925 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
926 
927 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
928 
929 	return result;
930 }
931 
932 static int pl2303_carrier_raised(struct usb_serial_port *port)
933 {
934 	struct pl2303_private *priv = usb_get_serial_port_data(port);
935 
936 	if (priv->line_status & UART_DCD)
937 		return 1;
938 
939 	return 0;
940 }
941 
942 static int pl2303_get_serial(struct tty_struct *tty,
943 			struct serial_struct *ss)
944 {
945 	struct usb_serial_port *port = tty->driver_data;
946 
947 	ss->type = PORT_16654;
948 	ss->line = port->minor;
949 	ss->port = port->port_number;
950 	ss->baud_base = 460800;
951 	return 0;
952 }
953 
954 static void pl2303_set_break(struct usb_serial_port *port, bool enable)
955 {
956 	struct usb_serial *serial = port->serial;
957 	u16 state;
958 	int result;
959 
960 	if (enable)
961 		state = BREAK_ON;
962 	else
963 		state = BREAK_OFF;
964 
965 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
966 			state == BREAK_OFF ? "off" : "on");
967 
968 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
969 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
970 				 0, NULL, 0, 100);
971 	if (result)
972 		dev_err(&port->dev, "error sending break = %d\n", result);
973 }
974 
975 static void pl2303_break_ctl(struct tty_struct *tty, int state)
976 {
977 	struct usb_serial_port *port = tty->driver_data;
978 
979 	pl2303_set_break(port, state);
980 }
981 
982 static void pl2303_update_line_status(struct usb_serial_port *port,
983 				      unsigned char *data,
984 				      unsigned int actual_length)
985 {
986 	struct usb_serial *serial = port->serial;
987 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
988 	struct pl2303_private *priv = usb_get_serial_port_data(port);
989 	struct tty_struct *tty;
990 	unsigned long flags;
991 	unsigned int status_idx = UART_STATE_INDEX;
992 	u8 status;
993 	u8 delta;
994 
995 	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
996 		status_idx = 0;
997 
998 	if (actual_length < status_idx + 1)
999 		return;
1000 
1001 	status = data[status_idx];
1002 
1003 	/* Save off the uart status for others to look at */
1004 	spin_lock_irqsave(&priv->lock, flags);
1005 	delta = priv->line_status ^ status;
1006 	priv->line_status = status;
1007 	spin_unlock_irqrestore(&priv->lock, flags);
1008 
1009 	if (status & UART_BREAK_ERROR)
1010 		usb_serial_handle_break(port);
1011 
1012 	if (delta & UART_STATE_MSR_MASK) {
1013 		if (delta & UART_CTS)
1014 			port->icount.cts++;
1015 		if (delta & UART_DSR)
1016 			port->icount.dsr++;
1017 		if (delta & UART_RING)
1018 			port->icount.rng++;
1019 		if (delta & UART_DCD) {
1020 			port->icount.dcd++;
1021 			tty = tty_port_tty_get(&port->port);
1022 			if (tty) {
1023 				usb_serial_handle_dcd_change(port, tty,
1024 							status & UART_DCD);
1025 				tty_kref_put(tty);
1026 			}
1027 		}
1028 
1029 		wake_up_interruptible(&port->port.delta_msr_wait);
1030 	}
1031 }
1032 
1033 static void pl2303_read_int_callback(struct urb *urb)
1034 {
1035 	struct usb_serial_port *port =  urb->context;
1036 	unsigned char *data = urb->transfer_buffer;
1037 	unsigned int actual_length = urb->actual_length;
1038 	int status = urb->status;
1039 	int retval;
1040 
1041 	switch (status) {
1042 	case 0:
1043 		/* success */
1044 		break;
1045 	case -ECONNRESET:
1046 	case -ENOENT:
1047 	case -ESHUTDOWN:
1048 		/* this urb is terminated, clean up */
1049 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1050 			__func__, status);
1051 		return;
1052 	default:
1053 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1054 			__func__, status);
1055 		goto exit;
1056 	}
1057 
1058 	usb_serial_debug_data(&port->dev, __func__,
1059 			      urb->actual_length, urb->transfer_buffer);
1060 
1061 	pl2303_update_line_status(port, data, actual_length);
1062 
1063 exit:
1064 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1065 	if (retval) {
1066 		dev_err(&port->dev,
1067 			"%s - usb_submit_urb failed with result %d\n",
1068 			__func__, retval);
1069 	}
1070 }
1071 
1072 static void pl2303_process_read_urb(struct urb *urb)
1073 {
1074 	struct usb_serial_port *port = urb->context;
1075 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1076 	unsigned char *data = urb->transfer_buffer;
1077 	char tty_flag = TTY_NORMAL;
1078 	unsigned long flags;
1079 	u8 line_status;
1080 	int i;
1081 
1082 	/* update line status */
1083 	spin_lock_irqsave(&priv->lock, flags);
1084 	line_status = priv->line_status;
1085 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1086 	spin_unlock_irqrestore(&priv->lock, flags);
1087 
1088 	if (!urb->actual_length)
1089 		return;
1090 
1091 	/*
1092 	 * Break takes precedence over parity, which takes precedence over
1093 	 * framing errors.
1094 	 */
1095 	if (line_status & UART_BREAK_ERROR)
1096 		tty_flag = TTY_BREAK;
1097 	else if (line_status & UART_PARITY_ERROR)
1098 		tty_flag = TTY_PARITY;
1099 	else if (line_status & UART_FRAME_ERROR)
1100 		tty_flag = TTY_FRAME;
1101 
1102 	if (tty_flag != TTY_NORMAL)
1103 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1104 								tty_flag);
1105 	/* overrun is special, not associated with a char */
1106 	if (line_status & UART_OVERRUN_ERROR)
1107 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1108 
1109 	if (port->sysrq) {
1110 		for (i = 0; i < urb->actual_length; ++i)
1111 			if (!usb_serial_handle_sysrq_char(port, data[i]))
1112 				tty_insert_flip_char(&port->port, data[i],
1113 						tty_flag);
1114 	} else {
1115 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1116 							urb->actual_length);
1117 	}
1118 
1119 	tty_flip_buffer_push(&port->port);
1120 }
1121 
1122 static struct usb_serial_driver pl2303_device = {
1123 	.driver = {
1124 		.owner =	THIS_MODULE,
1125 		.name =		"pl2303",
1126 	},
1127 	.id_table =		id_table,
1128 	.num_bulk_in =		1,
1129 	.num_bulk_out =		1,
1130 	.num_interrupt_in =	0,	/* see pl2303_calc_num_ports */
1131 	.bulk_in_size =		256,
1132 	.bulk_out_size =	256,
1133 	.open =			pl2303_open,
1134 	.close =		pl2303_close,
1135 	.dtr_rts =		pl2303_dtr_rts,
1136 	.carrier_raised =	pl2303_carrier_raised,
1137 	.get_serial =		pl2303_get_serial,
1138 	.break_ctl =		pl2303_break_ctl,
1139 	.set_termios =		pl2303_set_termios,
1140 	.tiocmget =		pl2303_tiocmget,
1141 	.tiocmset =		pl2303_tiocmset,
1142 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
1143 	.process_read_urb =	pl2303_process_read_urb,
1144 	.read_int_callback =	pl2303_read_int_callback,
1145 	.probe =		pl2303_probe,
1146 	.calc_num_ports =	pl2303_calc_num_ports,
1147 	.attach =		pl2303_startup,
1148 	.release =		pl2303_release,
1149 	.port_probe =		pl2303_port_probe,
1150 	.port_remove =		pl2303_port_remove,
1151 };
1152 
1153 static struct usb_serial_driver * const serial_drivers[] = {
1154 	&pl2303_device, NULL
1155 };
1156 
1157 module_usb_serial_driver(serial_drivers, id_table);
1158 
1159 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1160 MODULE_LICENSE("GPL v2");
1161