xref: /openbmc/linux/drivers/usb/serial/pl2303.c (revision 9a6b55ac)
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_LD960_PRODUCT_ID) },
103 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD960TA_PRODUCT_ID) },
104 	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
105 	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
106 	{ USB_DEVICE(HP_VENDOR_ID, HP_LM920_PRODUCT_ID) },
107 	{ USB_DEVICE(HP_VENDOR_ID, HP_LM940_PRODUCT_ID) },
108 	{ USB_DEVICE(HP_VENDOR_ID, HP_TD620_PRODUCT_ID) },
109 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
110 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
111 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
112 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
113 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
114 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
115 	{ USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
116 	{ }					/* Terminating entry */
117 };
118 
119 MODULE_DEVICE_TABLE(usb, id_table);
120 
121 #define SET_LINE_REQUEST_TYPE		0x21
122 #define SET_LINE_REQUEST		0x20
123 
124 #define SET_CONTROL_REQUEST_TYPE	0x21
125 #define SET_CONTROL_REQUEST		0x22
126 #define CONTROL_DTR			0x01
127 #define CONTROL_RTS			0x02
128 
129 #define BREAK_REQUEST_TYPE		0x21
130 #define BREAK_REQUEST			0x23
131 #define BREAK_ON			0xffff
132 #define BREAK_OFF			0x0000
133 
134 #define GET_LINE_REQUEST_TYPE		0xa1
135 #define GET_LINE_REQUEST		0x21
136 
137 #define VENDOR_WRITE_REQUEST_TYPE	0x40
138 #define VENDOR_WRITE_REQUEST		0x01
139 #define VENDOR_WRITE_NREQUEST		0x80
140 
141 #define VENDOR_READ_REQUEST_TYPE	0xc0
142 #define VENDOR_READ_REQUEST		0x01
143 #define VENDOR_READ_NREQUEST		0x81
144 
145 #define UART_STATE_INDEX		8
146 #define UART_STATE_MSR_MASK		0x8b
147 #define UART_STATE_TRANSIENT_MASK	0x74
148 #define UART_DCD			0x01
149 #define UART_DSR			0x02
150 #define UART_BREAK_ERROR		0x04
151 #define UART_RING			0x08
152 #define UART_FRAME_ERROR		0x10
153 #define UART_PARITY_ERROR		0x20
154 #define UART_OVERRUN_ERROR		0x40
155 #define UART_CTS			0x80
156 
157 #define PL2303_FLOWCTRL_MASK		0xf0
158 
159 #define PL2303_READ_TYPE_HX_STATUS	0x8080
160 
161 #define PL2303_HXN_RESET_REG		0x07
162 #define PL2303_HXN_RESET_UPSTREAM_PIPE	0x02
163 #define PL2303_HXN_RESET_DOWNSTREAM_PIPE	0x01
164 
165 #define PL2303_HXN_FLOWCTRL_REG		0x0a
166 #define PL2303_HXN_FLOWCTRL_MASK	0x1c
167 #define PL2303_HXN_FLOWCTRL_NONE	0x1c
168 #define PL2303_HXN_FLOWCTRL_RTS_CTS	0x18
169 #define PL2303_HXN_FLOWCTRL_XON_XOFF	0x0c
170 
171 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
172 
173 enum pl2303_type {
174 	TYPE_01,	/* Type 0 and 1 (difference unknown) */
175 	TYPE_HX,	/* HX version of the pl2303 chip */
176 	TYPE_HXN,	/* HXN version of the pl2303 chip */
177 	TYPE_COUNT
178 };
179 
180 struct pl2303_type_data {
181 	speed_t max_baud_rate;
182 	unsigned long quirks;
183 	unsigned int no_autoxonxoff:1;
184 };
185 
186 struct pl2303_serial_private {
187 	const struct pl2303_type_data *type;
188 	unsigned long quirks;
189 };
190 
191 struct pl2303_private {
192 	spinlock_t lock;
193 	u8 line_control;
194 	u8 line_status;
195 
196 	u8 line_settings[7];
197 };
198 
199 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
200 	[TYPE_01] = {
201 		.max_baud_rate		= 1228800,
202 		.quirks			= PL2303_QUIRK_LEGACY,
203 		.no_autoxonxoff		= true,
204 	},
205 	[TYPE_HX] = {
206 		.max_baud_rate		= 12000000,
207 	},
208 	[TYPE_HXN] = {
209 		.max_baud_rate		= 12000000,
210 	},
211 };
212 
213 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
214 							unsigned char buf[1])
215 {
216 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
217 	struct device *dev = &serial->interface->dev;
218 	u8 request;
219 	int res;
220 
221 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
222 		request = VENDOR_READ_NREQUEST;
223 	else
224 		request = VENDOR_READ_REQUEST;
225 
226 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
227 			request, VENDOR_READ_REQUEST_TYPE,
228 			value, 0, buf, 1, 100);
229 	if (res != 1) {
230 		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
231 								value, res);
232 		if (res >= 0)
233 			res = -EIO;
234 
235 		return res;
236 	}
237 
238 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
239 
240 	return 0;
241 }
242 
243 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
244 {
245 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
246 	struct device *dev = &serial->interface->dev;
247 	u8 request;
248 	int res;
249 
250 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
251 
252 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
253 		request = VENDOR_WRITE_NREQUEST;
254 	else
255 		request = VENDOR_WRITE_REQUEST;
256 
257 	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
258 			request, VENDOR_WRITE_REQUEST_TYPE,
259 			value, index, NULL, 0, 100);
260 	if (res) {
261 		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
262 								value, res);
263 		return res;
264 	}
265 
266 	return 0;
267 }
268 
269 static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
270 {
271 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
272 	int ret = 0;
273 	u8 *buf;
274 
275 	buf = kmalloc(1, GFP_KERNEL);
276 	if (!buf)
277 		return -ENOMEM;
278 
279 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
280 		ret = pl2303_vendor_read(serial, reg, buf);
281 	else
282 		ret = pl2303_vendor_read(serial, reg | 0x80, buf);
283 
284 	if (ret)
285 		goto out_free;
286 
287 	*buf &= ~mask;
288 	*buf |= val & mask;
289 
290 	ret = pl2303_vendor_write(serial, reg, *buf);
291 out_free:
292 	kfree(buf);
293 
294 	return ret;
295 }
296 
297 static int pl2303_probe(struct usb_serial *serial,
298 					const struct usb_device_id *id)
299 {
300 	usb_set_serial_data(serial, (void *)id->driver_info);
301 
302 	return 0;
303 }
304 
305 /*
306  * Use interrupt endpoint from first interface if available.
307  *
308  * This is needed due to the looney way its endpoints are set up.
309  */
310 static int pl2303_endpoint_hack(struct usb_serial *serial,
311 					struct usb_serial_endpoints *epds)
312 {
313 	struct usb_interface *interface = serial->interface;
314 	struct usb_device *dev = serial->dev;
315 	struct device *ddev = &interface->dev;
316 	struct usb_host_interface *iface_desc;
317 	struct usb_endpoint_descriptor *endpoint;
318 	unsigned int i;
319 
320 	if (interface == dev->actconfig->interface[0])
321 		return 0;
322 
323 	/* check out the endpoints of the other interface */
324 	iface_desc = dev->actconfig->interface[0]->cur_altsetting;
325 
326 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
327 		endpoint = &iface_desc->endpoint[i].desc;
328 
329 		if (!usb_endpoint_is_int_in(endpoint))
330 			continue;
331 
332 		dev_dbg(ddev, "found interrupt in on separate interface\n");
333 		if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
334 			epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
335 	}
336 
337 	return 0;
338 }
339 
340 static int pl2303_calc_num_ports(struct usb_serial *serial,
341 					struct usb_serial_endpoints *epds)
342 {
343 	unsigned long quirks = (unsigned long)usb_get_serial_data(serial);
344 	struct device *dev = &serial->interface->dev;
345 	int ret;
346 
347 	if (quirks & PL2303_QUIRK_ENDPOINT_HACK) {
348 		ret = pl2303_endpoint_hack(serial, epds);
349 		if (ret)
350 			return ret;
351 	}
352 
353 	if (epds->num_interrupt_in < 1) {
354 		dev_err(dev, "required interrupt-in endpoint missing\n");
355 		return -ENODEV;
356 	}
357 
358 	return 1;
359 }
360 
361 static int pl2303_startup(struct usb_serial *serial)
362 {
363 	struct pl2303_serial_private *spriv;
364 	enum pl2303_type type = TYPE_01;
365 	unsigned char *buf;
366 	int res;
367 
368 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
369 	if (!spriv)
370 		return -ENOMEM;
371 
372 	buf = kmalloc(1, GFP_KERNEL);
373 	if (!buf) {
374 		kfree(spriv);
375 		return -ENOMEM;
376 	}
377 
378 	if (serial->dev->descriptor.bDeviceClass == 0x02)
379 		type = TYPE_01;		/* type 0 */
380 	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
381 		type = TYPE_HX;
382 	else if (serial->dev->descriptor.bDeviceClass == 0x00)
383 		type = TYPE_01;		/* type 1 */
384 	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
385 		type = TYPE_01;		/* type 1 */
386 	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
387 
388 	if (type == TYPE_HX) {
389 		res = usb_control_msg(serial->dev,
390 				usb_rcvctrlpipe(serial->dev, 0),
391 				VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
392 				PL2303_READ_TYPE_HX_STATUS, 0, buf, 1, 100);
393 		if (res != 1)
394 			type = TYPE_HXN;
395 	}
396 
397 	spriv->type = &pl2303_type_data[type];
398 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
399 	spriv->quirks |= spriv->type->quirks;
400 
401 	usb_set_serial_data(serial, spriv);
402 
403 	if (type != TYPE_HXN) {
404 		pl2303_vendor_read(serial, 0x8484, buf);
405 		pl2303_vendor_write(serial, 0x0404, 0);
406 		pl2303_vendor_read(serial, 0x8484, buf);
407 		pl2303_vendor_read(serial, 0x8383, buf);
408 		pl2303_vendor_read(serial, 0x8484, buf);
409 		pl2303_vendor_write(serial, 0x0404, 1);
410 		pl2303_vendor_read(serial, 0x8484, buf);
411 		pl2303_vendor_read(serial, 0x8383, buf);
412 		pl2303_vendor_write(serial, 0, 1);
413 		pl2303_vendor_write(serial, 1, 0);
414 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
415 			pl2303_vendor_write(serial, 2, 0x24);
416 		else
417 			pl2303_vendor_write(serial, 2, 0x44);
418 	}
419 
420 	kfree(buf);
421 
422 	return 0;
423 }
424 
425 static void pl2303_release(struct usb_serial *serial)
426 {
427 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
428 
429 	kfree(spriv);
430 }
431 
432 static int pl2303_port_probe(struct usb_serial_port *port)
433 {
434 	struct pl2303_private *priv;
435 
436 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
437 	if (!priv)
438 		return -ENOMEM;
439 
440 	spin_lock_init(&priv->lock);
441 
442 	usb_set_serial_port_data(port, priv);
443 
444 	port->port.drain_delay = 256;
445 
446 	return 0;
447 }
448 
449 static int pl2303_port_remove(struct usb_serial_port *port)
450 {
451 	struct pl2303_private *priv = usb_get_serial_port_data(port);
452 
453 	kfree(priv);
454 
455 	return 0;
456 }
457 
458 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
459 {
460 	struct usb_device *dev = port->serial->dev;
461 	int retval;
462 
463 	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
464 
465 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
466 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
467 				 value, 0, NULL, 0, 100);
468 	if (retval)
469 		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
470 
471 	return retval;
472 }
473 
474 /*
475  * Returns the nearest supported baud rate that can be set directly without
476  * using divisors.
477  */
478 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
479 {
480 	static const speed_t baud_sup[] = {
481 		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
482 		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
483 		614400, 921600, 1228800, 2457600, 3000000, 6000000
484 	};
485 
486 	unsigned i;
487 
488 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
489 		if (baud_sup[i] > baud)
490 			break;
491 	}
492 
493 	if (i == ARRAY_SIZE(baud_sup))
494 		baud = baud_sup[i - 1];
495 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
496 		baud = baud_sup[i - 1];
497 	else
498 		baud = baud_sup[i];
499 
500 	return baud;
501 }
502 
503 /*
504  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
505  *       use 9600 baud.
506  */
507 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
508 								speed_t baud)
509 {
510 	put_unaligned_le32(baud, buf);
511 
512 	return baud;
513 }
514 
515 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
516 								speed_t baud)
517 {
518 	unsigned int baseline, mantissa, exponent;
519 
520 	/*
521 	 * Apparently the formula is:
522 	 *   baudrate = 12M * 32 / (mantissa * 4^exponent)
523 	 * where
524 	 *   mantissa = buf[8:0]
525 	 *   exponent = buf[11:9]
526 	 */
527 	baseline = 12000000 * 32;
528 	mantissa = baseline / baud;
529 	if (mantissa == 0)
530 		mantissa = 1;	/* Avoid dividing by zero if baud > 32*12M. */
531 	exponent = 0;
532 	while (mantissa >= 512) {
533 		if (exponent < 7) {
534 			mantissa >>= 2;	/* divide by 4 */
535 			exponent++;
536 		} else {
537 			/* Exponent is maxed. Trim mantissa and leave. */
538 			mantissa = 511;
539 			break;
540 		}
541 	}
542 
543 	buf[3] = 0x80;
544 	buf[2] = 0;
545 	buf[1] = exponent << 1 | mantissa >> 8;
546 	buf[0] = mantissa & 0xff;
547 
548 	/* Calculate and return the exact baud rate. */
549 	baud = (baseline / mantissa) >> (exponent << 1);
550 
551 	return baud;
552 }
553 
554 static void pl2303_encode_baud_rate(struct tty_struct *tty,
555 					struct usb_serial_port *port,
556 					u8 buf[4])
557 {
558 	struct usb_serial *serial = port->serial;
559 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
560 	speed_t	baud_sup;
561 	speed_t baud;
562 
563 	baud = tty_get_baud_rate(tty);
564 	dev_dbg(&port->dev, "baud requested = %u\n", baud);
565 	if (!baud)
566 		return;
567 
568 	if (spriv->type->max_baud_rate)
569 		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
570 	/*
571 	 * Use direct method for supported baud rates, otherwise use divisors.
572 	 */
573 	baud_sup = pl2303_get_supported_baud_rate(baud);
574 
575 	if (baud == baud_sup)
576 		baud = pl2303_encode_baud_rate_direct(buf, baud);
577 	else
578 		baud = pl2303_encode_baud_rate_divisor(buf, baud);
579 
580 	/* Save resulting baud rate */
581 	tty_encode_baud_rate(tty, baud, baud);
582 	dev_dbg(&port->dev, "baud set = %u\n", baud);
583 }
584 
585 static int pl2303_get_line_request(struct usb_serial_port *port,
586 							unsigned char buf[7])
587 {
588 	struct usb_device *udev = port->serial->dev;
589 	int ret;
590 
591 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
592 				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
593 				0, 0, buf, 7, 100);
594 	if (ret != 7) {
595 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
596 
597 		if (ret >= 0)
598 			ret = -EIO;
599 
600 		return ret;
601 	}
602 
603 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
604 
605 	return 0;
606 }
607 
608 static int pl2303_set_line_request(struct usb_serial_port *port,
609 							unsigned char buf[7])
610 {
611 	struct usb_device *udev = port->serial->dev;
612 	int ret;
613 
614 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
615 				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
616 				0, 0, buf, 7, 100);
617 	if (ret < 0) {
618 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
619 		return ret;
620 	}
621 
622 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
623 
624 	return 0;
625 }
626 
627 static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
628 {
629 	bool ixon_change;
630 
631 	ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
632 			a->c_cc[VSTART] != b->c_cc[VSTART] ||
633 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
634 
635 	return tty_termios_hw_change(a, b) || ixon_change;
636 }
637 
638 static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
639 {
640 	if (!I_IXON(tty) || I_IXANY(tty))
641 		return false;
642 
643 	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
644 		return false;
645 
646 	if (type->no_autoxonxoff)
647 		return false;
648 
649 	return true;
650 }
651 
652 static void pl2303_set_termios(struct tty_struct *tty,
653 		struct usb_serial_port *port, struct ktermios *old_termios)
654 {
655 	struct usb_serial *serial = port->serial;
656 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
657 	struct pl2303_private *priv = usb_get_serial_port_data(port);
658 	unsigned long flags;
659 	unsigned char *buf;
660 	int ret;
661 	u8 control;
662 
663 	if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
664 		return;
665 
666 	buf = kzalloc(7, GFP_KERNEL);
667 	if (!buf) {
668 		/* Report back no change occurred */
669 		if (old_termios)
670 			tty->termios = *old_termios;
671 		return;
672 	}
673 
674 	pl2303_get_line_request(port, buf);
675 
676 	switch (C_CSIZE(tty)) {
677 	case CS5:
678 		buf[6] = 5;
679 		break;
680 	case CS6:
681 		buf[6] = 6;
682 		break;
683 	case CS7:
684 		buf[6] = 7;
685 		break;
686 	default:
687 	case CS8:
688 		buf[6] = 8;
689 	}
690 	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
691 
692 	/* For reference buf[0]:buf[3] baud rate value */
693 	pl2303_encode_baud_rate(tty, port, &buf[0]);
694 
695 	/* For reference buf[4]=0 is 1 stop bits */
696 	/* For reference buf[4]=1 is 1.5 stop bits */
697 	/* For reference buf[4]=2 is 2 stop bits */
698 	if (C_CSTOPB(tty)) {
699 		/*
700 		 * NOTE: Comply with "real" UARTs / RS232:
701 		 *       use 1.5 instead of 2 stop bits with 5 data bits
702 		 */
703 		if (C_CSIZE(tty) == CS5) {
704 			buf[4] = 1;
705 			dev_dbg(&port->dev, "stop bits = 1.5\n");
706 		} else {
707 			buf[4] = 2;
708 			dev_dbg(&port->dev, "stop bits = 2\n");
709 		}
710 	} else {
711 		buf[4] = 0;
712 		dev_dbg(&port->dev, "stop bits = 1\n");
713 	}
714 
715 	if (C_PARENB(tty)) {
716 		/* For reference buf[5]=0 is none parity */
717 		/* For reference buf[5]=1 is odd parity */
718 		/* For reference buf[5]=2 is even parity */
719 		/* For reference buf[5]=3 is mark parity */
720 		/* For reference buf[5]=4 is space parity */
721 		if (C_PARODD(tty)) {
722 			if (C_CMSPAR(tty)) {
723 				buf[5] = 3;
724 				dev_dbg(&port->dev, "parity = mark\n");
725 			} else {
726 				buf[5] = 1;
727 				dev_dbg(&port->dev, "parity = odd\n");
728 			}
729 		} else {
730 			if (C_CMSPAR(tty)) {
731 				buf[5] = 4;
732 				dev_dbg(&port->dev, "parity = space\n");
733 			} else {
734 				buf[5] = 2;
735 				dev_dbg(&port->dev, "parity = even\n");
736 			}
737 		}
738 	} else {
739 		buf[5] = 0;
740 		dev_dbg(&port->dev, "parity = none\n");
741 	}
742 
743 	/*
744 	 * Some PL2303 are known to lose bytes if you change serial settings
745 	 * even to the same values as before. Thus we actually need to filter
746 	 * in this specific case.
747 	 *
748 	 * Note that the tty_termios_hw_change check above is not sufficient
749 	 * as a previously requested baud rate may differ from the one
750 	 * actually used (and stored in old_termios).
751 	 *
752 	 * NOTE: No additional locking needed for line_settings as it is
753 	 *       only used in set_termios, which is serialised against itself.
754 	 */
755 	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
756 		ret = pl2303_set_line_request(port, buf);
757 		if (!ret)
758 			memcpy(priv->line_settings, buf, 7);
759 	}
760 
761 	/* change control lines if we are switching to or from B0 */
762 	spin_lock_irqsave(&priv->lock, flags);
763 	control = priv->line_control;
764 	if (C_BAUD(tty) == B0)
765 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
766 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
767 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
768 	if (control != priv->line_control) {
769 		control = priv->line_control;
770 		spin_unlock_irqrestore(&priv->lock, flags);
771 		pl2303_set_control_lines(port, control);
772 	} else {
773 		spin_unlock_irqrestore(&priv->lock, flags);
774 	}
775 
776 	if (C_CRTSCTS(tty)) {
777 		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
778 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
779 		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
780 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
781 					PL2303_HXN_FLOWCTRL_MASK,
782 					PL2303_HXN_FLOWCTRL_RTS_CTS);
783 		} else {
784 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
785 		}
786 	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
787 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
788 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
789 					PL2303_HXN_FLOWCTRL_MASK,
790 					PL2303_HXN_FLOWCTRL_XON_XOFF);
791 		} else {
792 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
793 		}
794 	} else {
795 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
796 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
797 					PL2303_HXN_FLOWCTRL_MASK,
798 					PL2303_HXN_FLOWCTRL_NONE);
799 		} else {
800 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
801 		}
802 	}
803 
804 	kfree(buf);
805 }
806 
807 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
808 {
809 	struct pl2303_private *priv = usb_get_serial_port_data(port);
810 	unsigned long flags;
811 	u8 control;
812 
813 	spin_lock_irqsave(&priv->lock, flags);
814 	if (on)
815 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
816 	else
817 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
818 	control = priv->line_control;
819 	spin_unlock_irqrestore(&priv->lock, flags);
820 
821 	pl2303_set_control_lines(port, control);
822 }
823 
824 static void pl2303_close(struct usb_serial_port *port)
825 {
826 	usb_serial_generic_close(port);
827 	usb_kill_urb(port->interrupt_in_urb);
828 	pl2303_set_break(port, false);
829 }
830 
831 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
832 {
833 	struct usb_serial *serial = port->serial;
834 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
835 	int result;
836 
837 	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
838 		usb_clear_halt(serial->dev, port->write_urb->pipe);
839 		usb_clear_halt(serial->dev, port->read_urb->pipe);
840 	} else {
841 		/* reset upstream data pipes */
842 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
843 			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
844 					PL2303_HXN_RESET_UPSTREAM_PIPE |
845 					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
846 		} else {
847 			pl2303_vendor_write(serial, 8, 0);
848 			pl2303_vendor_write(serial, 9, 0);
849 		}
850 	}
851 
852 	/* Setup termios */
853 	if (tty)
854 		pl2303_set_termios(tty, port, NULL);
855 
856 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
857 	if (result) {
858 		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
859 			result);
860 		return result;
861 	}
862 
863 	result = usb_serial_generic_open(tty, port);
864 	if (result) {
865 		usb_kill_urb(port->interrupt_in_urb);
866 		return result;
867 	}
868 
869 	return 0;
870 }
871 
872 static int pl2303_tiocmset(struct tty_struct *tty,
873 			   unsigned int set, unsigned int clear)
874 {
875 	struct usb_serial_port *port = tty->driver_data;
876 	struct pl2303_private *priv = usb_get_serial_port_data(port);
877 	unsigned long flags;
878 	u8 control;
879 	int ret;
880 
881 	spin_lock_irqsave(&priv->lock, flags);
882 	if (set & TIOCM_RTS)
883 		priv->line_control |= CONTROL_RTS;
884 	if (set & TIOCM_DTR)
885 		priv->line_control |= CONTROL_DTR;
886 	if (clear & TIOCM_RTS)
887 		priv->line_control &= ~CONTROL_RTS;
888 	if (clear & TIOCM_DTR)
889 		priv->line_control &= ~CONTROL_DTR;
890 	control = priv->line_control;
891 	spin_unlock_irqrestore(&priv->lock, flags);
892 
893 	ret = pl2303_set_control_lines(port, control);
894 	if (ret)
895 		return usb_translate_errors(ret);
896 
897 	return 0;
898 }
899 
900 static int pl2303_tiocmget(struct tty_struct *tty)
901 {
902 	struct usb_serial_port *port = tty->driver_data;
903 	struct pl2303_private *priv = usb_get_serial_port_data(port);
904 	unsigned long flags;
905 	unsigned int mcr;
906 	unsigned int status;
907 	unsigned int result;
908 
909 	spin_lock_irqsave(&priv->lock, flags);
910 	mcr = priv->line_control;
911 	status = priv->line_status;
912 	spin_unlock_irqrestore(&priv->lock, flags);
913 
914 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
915 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
916 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
917 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
918 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
919 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
920 
921 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
922 
923 	return result;
924 }
925 
926 static int pl2303_carrier_raised(struct usb_serial_port *port)
927 {
928 	struct pl2303_private *priv = usb_get_serial_port_data(port);
929 
930 	if (priv->line_status & UART_DCD)
931 		return 1;
932 
933 	return 0;
934 }
935 
936 static int pl2303_get_serial(struct tty_struct *tty,
937 			struct serial_struct *ss)
938 {
939 	struct usb_serial_port *port = tty->driver_data;
940 
941 	ss->type = PORT_16654;
942 	ss->line = port->minor;
943 	ss->port = port->port_number;
944 	ss->baud_base = 460800;
945 	return 0;
946 }
947 
948 static void pl2303_set_break(struct usb_serial_port *port, bool enable)
949 {
950 	struct usb_serial *serial = port->serial;
951 	u16 state;
952 	int result;
953 
954 	if (enable)
955 		state = BREAK_ON;
956 	else
957 		state = BREAK_OFF;
958 
959 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
960 			state == BREAK_OFF ? "off" : "on");
961 
962 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
963 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
964 				 0, NULL, 0, 100);
965 	if (result)
966 		dev_err(&port->dev, "error sending break = %d\n", result);
967 }
968 
969 static void pl2303_break_ctl(struct tty_struct *tty, int state)
970 {
971 	struct usb_serial_port *port = tty->driver_data;
972 
973 	pl2303_set_break(port, state);
974 }
975 
976 static void pl2303_update_line_status(struct usb_serial_port *port,
977 				      unsigned char *data,
978 				      unsigned int actual_length)
979 {
980 	struct usb_serial *serial = port->serial;
981 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
982 	struct pl2303_private *priv = usb_get_serial_port_data(port);
983 	struct tty_struct *tty;
984 	unsigned long flags;
985 	unsigned int status_idx = UART_STATE_INDEX;
986 	u8 status;
987 	u8 delta;
988 
989 	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
990 		status_idx = 0;
991 
992 	if (actual_length < status_idx + 1)
993 		return;
994 
995 	status = data[status_idx];
996 
997 	/* Save off the uart status for others to look at */
998 	spin_lock_irqsave(&priv->lock, flags);
999 	delta = priv->line_status ^ status;
1000 	priv->line_status = status;
1001 	spin_unlock_irqrestore(&priv->lock, flags);
1002 
1003 	if (status & UART_BREAK_ERROR)
1004 		usb_serial_handle_break(port);
1005 
1006 	if (delta & UART_STATE_MSR_MASK) {
1007 		if (delta & UART_CTS)
1008 			port->icount.cts++;
1009 		if (delta & UART_DSR)
1010 			port->icount.dsr++;
1011 		if (delta & UART_RING)
1012 			port->icount.rng++;
1013 		if (delta & UART_DCD) {
1014 			port->icount.dcd++;
1015 			tty = tty_port_tty_get(&port->port);
1016 			if (tty) {
1017 				usb_serial_handle_dcd_change(port, tty,
1018 							status & UART_DCD);
1019 				tty_kref_put(tty);
1020 			}
1021 		}
1022 
1023 		wake_up_interruptible(&port->port.delta_msr_wait);
1024 	}
1025 }
1026 
1027 static void pl2303_read_int_callback(struct urb *urb)
1028 {
1029 	struct usb_serial_port *port =  urb->context;
1030 	unsigned char *data = urb->transfer_buffer;
1031 	unsigned int actual_length = urb->actual_length;
1032 	int status = urb->status;
1033 	int retval;
1034 
1035 	switch (status) {
1036 	case 0:
1037 		/* success */
1038 		break;
1039 	case -ECONNRESET:
1040 	case -ENOENT:
1041 	case -ESHUTDOWN:
1042 		/* this urb is terminated, clean up */
1043 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1044 			__func__, status);
1045 		return;
1046 	default:
1047 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1048 			__func__, status);
1049 		goto exit;
1050 	}
1051 
1052 	usb_serial_debug_data(&port->dev, __func__,
1053 			      urb->actual_length, urb->transfer_buffer);
1054 
1055 	pl2303_update_line_status(port, data, actual_length);
1056 
1057 exit:
1058 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1059 	if (retval) {
1060 		dev_err(&port->dev,
1061 			"%s - usb_submit_urb failed with result %d\n",
1062 			__func__, retval);
1063 	}
1064 }
1065 
1066 static void pl2303_process_read_urb(struct urb *urb)
1067 {
1068 	struct usb_serial_port *port = urb->context;
1069 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1070 	unsigned char *data = urb->transfer_buffer;
1071 	char tty_flag = TTY_NORMAL;
1072 	unsigned long flags;
1073 	u8 line_status;
1074 	int i;
1075 
1076 	/* update line status */
1077 	spin_lock_irqsave(&priv->lock, flags);
1078 	line_status = priv->line_status;
1079 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1080 	spin_unlock_irqrestore(&priv->lock, flags);
1081 
1082 	if (!urb->actual_length)
1083 		return;
1084 
1085 	/*
1086 	 * Break takes precedence over parity, which takes precedence over
1087 	 * framing errors.
1088 	 */
1089 	if (line_status & UART_BREAK_ERROR)
1090 		tty_flag = TTY_BREAK;
1091 	else if (line_status & UART_PARITY_ERROR)
1092 		tty_flag = TTY_PARITY;
1093 	else if (line_status & UART_FRAME_ERROR)
1094 		tty_flag = TTY_FRAME;
1095 
1096 	if (tty_flag != TTY_NORMAL)
1097 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1098 								tty_flag);
1099 	/* overrun is special, not associated with a char */
1100 	if (line_status & UART_OVERRUN_ERROR)
1101 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1102 
1103 	if (port->port.console && port->sysrq) {
1104 		for (i = 0; i < urb->actual_length; ++i)
1105 			if (!usb_serial_handle_sysrq_char(port, data[i]))
1106 				tty_insert_flip_char(&port->port, data[i],
1107 						tty_flag);
1108 	} else {
1109 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1110 							urb->actual_length);
1111 	}
1112 
1113 	tty_flip_buffer_push(&port->port);
1114 }
1115 
1116 static struct usb_serial_driver pl2303_device = {
1117 	.driver = {
1118 		.owner =	THIS_MODULE,
1119 		.name =		"pl2303",
1120 	},
1121 	.id_table =		id_table,
1122 	.num_bulk_in =		1,
1123 	.num_bulk_out =		1,
1124 	.num_interrupt_in =	0,	/* see pl2303_calc_num_ports */
1125 	.bulk_in_size =		256,
1126 	.bulk_out_size =	256,
1127 	.open =			pl2303_open,
1128 	.close =		pl2303_close,
1129 	.dtr_rts =		pl2303_dtr_rts,
1130 	.carrier_raised =	pl2303_carrier_raised,
1131 	.get_serial =		pl2303_get_serial,
1132 	.break_ctl =		pl2303_break_ctl,
1133 	.set_termios =		pl2303_set_termios,
1134 	.tiocmget =		pl2303_tiocmget,
1135 	.tiocmset =		pl2303_tiocmset,
1136 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
1137 	.process_read_urb =	pl2303_process_read_urb,
1138 	.read_int_callback =	pl2303_read_int_callback,
1139 	.probe =		pl2303_probe,
1140 	.calc_num_ports =	pl2303_calc_num_ports,
1141 	.attach =		pl2303_startup,
1142 	.release =		pl2303_release,
1143 	.port_probe =		pl2303_port_probe,
1144 	.port_remove =		pl2303_port_remove,
1145 };
1146 
1147 static struct usb_serial_driver * const serial_drivers[] = {
1148 	&pl2303_device, NULL
1149 };
1150 
1151 module_usb_serial_driver(serial_drivers, id_table);
1152 
1153 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1154 MODULE_LICENSE("GPL v2");
1155