xref: /linux/drivers/usb/serial/pl2303.c (revision 22511e665eadc2c49021886d07aaef39db90ca82)
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(ADLINK_VENDOR_ID, ADLINK_ND6530GC_PRODUCT_ID) },
117 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
118 	{ USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
119 	{ USB_DEVICE(IBM_VENDOR_ID, IBM_PRODUCT_ID) },
120 	{ }					/* Terminating entry */
121 };
122 
123 MODULE_DEVICE_TABLE(usb, id_table);
124 
125 #define SET_LINE_REQUEST_TYPE		0x21
126 #define SET_LINE_REQUEST		0x20
127 
128 #define SET_CONTROL_REQUEST_TYPE	0x21
129 #define SET_CONTROL_REQUEST		0x22
130 #define CONTROL_DTR			0x01
131 #define CONTROL_RTS			0x02
132 
133 #define BREAK_REQUEST_TYPE		0x21
134 #define BREAK_REQUEST			0x23
135 #define BREAK_ON			0xffff
136 #define BREAK_OFF			0x0000
137 
138 #define GET_LINE_REQUEST_TYPE		0xa1
139 #define GET_LINE_REQUEST		0x21
140 
141 #define VENDOR_WRITE_REQUEST_TYPE	0x40
142 #define VENDOR_WRITE_REQUEST		0x01
143 #define VENDOR_WRITE_NREQUEST		0x80
144 
145 #define VENDOR_READ_REQUEST_TYPE	0xc0
146 #define VENDOR_READ_REQUEST		0x01
147 #define VENDOR_READ_NREQUEST		0x81
148 
149 #define UART_STATE_INDEX		8
150 #define UART_STATE_MSR_MASK		0x8b
151 #define UART_STATE_TRANSIENT_MASK	0x74
152 #define UART_DCD			0x01
153 #define UART_DSR			0x02
154 #define UART_BREAK_ERROR		0x04
155 #define UART_RING			0x08
156 #define UART_FRAME_ERROR		0x10
157 #define UART_PARITY_ERROR		0x20
158 #define UART_OVERRUN_ERROR		0x40
159 #define UART_CTS			0x80
160 
161 #define PL2303_FLOWCTRL_MASK		0xf0
162 
163 #define PL2303_READ_TYPE_HX_STATUS	0x8080
164 
165 #define PL2303_HXN_RESET_REG		0x07
166 #define PL2303_HXN_RESET_UPSTREAM_PIPE	0x02
167 #define PL2303_HXN_RESET_DOWNSTREAM_PIPE	0x01
168 
169 #define PL2303_HXN_FLOWCTRL_REG		0x0a
170 #define PL2303_HXN_FLOWCTRL_MASK	0x1c
171 #define PL2303_HXN_FLOWCTRL_NONE	0x1c
172 #define PL2303_HXN_FLOWCTRL_RTS_CTS	0x18
173 #define PL2303_HXN_FLOWCTRL_XON_XOFF	0x0c
174 
175 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
176 
177 enum pl2303_type {
178 	TYPE_H,
179 	TYPE_HX,
180 	TYPE_TA,
181 	TYPE_TB,
182 	TYPE_HXD,
183 	TYPE_HXN,
184 	TYPE_COUNT
185 };
186 
187 struct pl2303_type_data {
188 	const char *name;
189 	speed_t max_baud_rate;
190 	unsigned long quirks;
191 	unsigned int no_autoxonxoff:1;
192 	unsigned int no_divisors:1;
193 	unsigned int alt_divisors:1;
194 };
195 
196 struct pl2303_serial_private {
197 	const struct pl2303_type_data *type;
198 	unsigned long quirks;
199 };
200 
201 struct pl2303_private {
202 	spinlock_t lock;
203 	u8 line_control;
204 	u8 line_status;
205 
206 	u8 line_settings[7];
207 };
208 
209 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
210 	[TYPE_H] = {
211 		.name			= "H",
212 		.max_baud_rate		= 1228800,
213 		.quirks			= PL2303_QUIRK_LEGACY,
214 		.no_autoxonxoff		= true,
215 	},
216 	[TYPE_HX] = {
217 		.name			= "HX",
218 		.max_baud_rate		= 6000000,
219 	},
220 	[TYPE_TA] = {
221 		.name			= "TA",
222 		.max_baud_rate		= 6000000,
223 		.alt_divisors		= true,
224 	},
225 	[TYPE_TB] = {
226 		.name			= "TB",
227 		.max_baud_rate		= 12000000,
228 		.alt_divisors		= true,
229 	},
230 	[TYPE_HXD] = {
231 		.name			= "HXD",
232 		.max_baud_rate		= 12000000,
233 	},
234 	[TYPE_HXN] = {
235 		.name			= "G",
236 		.max_baud_rate		= 12000000,
237 		.no_divisors		= true,
238 	},
239 };
240 
241 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
242 							unsigned char buf[1])
243 {
244 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
245 	struct device *dev = &serial->interface->dev;
246 	u8 request;
247 	int res;
248 
249 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
250 		request = VENDOR_READ_NREQUEST;
251 	else
252 		request = VENDOR_READ_REQUEST;
253 
254 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
255 			request, VENDOR_READ_REQUEST_TYPE,
256 			value, 0, buf, 1, 100);
257 	if (res != 1) {
258 		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
259 								value, res);
260 		if (res >= 0)
261 			res = -EIO;
262 
263 		return res;
264 	}
265 
266 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
267 
268 	return 0;
269 }
270 
271 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
272 {
273 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
274 	struct device *dev = &serial->interface->dev;
275 	u8 request;
276 	int res;
277 
278 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
279 
280 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
281 		request = VENDOR_WRITE_NREQUEST;
282 	else
283 		request = VENDOR_WRITE_REQUEST;
284 
285 	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
286 			request, VENDOR_WRITE_REQUEST_TYPE,
287 			value, index, NULL, 0, 100);
288 	if (res) {
289 		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
290 								value, res);
291 		return res;
292 	}
293 
294 	return 0;
295 }
296 
297 static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
298 {
299 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
300 	int ret = 0;
301 	u8 *buf;
302 
303 	buf = kmalloc(1, GFP_KERNEL);
304 	if (!buf)
305 		return -ENOMEM;
306 
307 	if (spriv->type == &pl2303_type_data[TYPE_HXN])
308 		ret = pl2303_vendor_read(serial, reg, buf);
309 	else
310 		ret = pl2303_vendor_read(serial, reg | 0x80, buf);
311 
312 	if (ret)
313 		goto out_free;
314 
315 	*buf &= ~mask;
316 	*buf |= val & mask;
317 
318 	ret = pl2303_vendor_write(serial, reg, *buf);
319 out_free:
320 	kfree(buf);
321 
322 	return ret;
323 }
324 
325 static int pl2303_probe(struct usb_serial *serial,
326 					const struct usb_device_id *id)
327 {
328 	usb_set_serial_data(serial, (void *)id->driver_info);
329 
330 	return 0;
331 }
332 
333 /*
334  * Use interrupt endpoint from first interface if available.
335  *
336  * This is needed due to the looney way its endpoints are set up.
337  */
338 static int pl2303_endpoint_hack(struct usb_serial *serial,
339 					struct usb_serial_endpoints *epds)
340 {
341 	struct usb_interface *interface = serial->interface;
342 	struct usb_device *dev = serial->dev;
343 	struct device *ddev = &interface->dev;
344 	struct usb_host_interface *iface_desc;
345 	struct usb_endpoint_descriptor *endpoint;
346 	unsigned int i;
347 
348 	if (interface == dev->actconfig->interface[0])
349 		return 0;
350 
351 	/* check out the endpoints of the other interface */
352 	iface_desc = dev->actconfig->interface[0]->cur_altsetting;
353 
354 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
355 		endpoint = &iface_desc->endpoint[i].desc;
356 
357 		if (!usb_endpoint_is_int_in(endpoint))
358 			continue;
359 
360 		dev_dbg(ddev, "found interrupt in on separate interface\n");
361 		if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
362 			epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
363 	}
364 
365 	return 0;
366 }
367 
368 static int pl2303_calc_num_ports(struct usb_serial *serial,
369 					struct usb_serial_endpoints *epds)
370 {
371 	unsigned long quirks = (unsigned long)usb_get_serial_data(serial);
372 	struct device *dev = &serial->interface->dev;
373 	int ret;
374 
375 	if (quirks & PL2303_QUIRK_ENDPOINT_HACK) {
376 		ret = pl2303_endpoint_hack(serial, epds);
377 		if (ret)
378 			return ret;
379 	}
380 
381 	if (epds->num_interrupt_in < 1) {
382 		dev_err(dev, "required interrupt-in endpoint missing\n");
383 		return -ENODEV;
384 	}
385 
386 	return 1;
387 }
388 
389 static bool pl2303_supports_hx_status(struct usb_serial *serial)
390 {
391 	int ret;
392 	u8 buf;
393 
394 	ret = usb_control_msg_recv(serial->dev, 0, VENDOR_READ_REQUEST,
395 			VENDOR_READ_REQUEST_TYPE, PL2303_READ_TYPE_HX_STATUS,
396 			0, &buf, 1, 100, GFP_KERNEL);
397 
398 	return ret == 0;
399 }
400 
401 static int pl2303_detect_type(struct usb_serial *serial)
402 {
403 	struct usb_device_descriptor *desc = &serial->dev->descriptor;
404 	u16 bcdDevice, bcdUSB;
405 
406 	/*
407 	 * Legacy PL2303H, variants 0 and 1 (difference unknown).
408 	 */
409 	if (desc->bDeviceClass == 0x02)
410 		return TYPE_H;		/* variant 0 */
411 
412 	if (desc->bMaxPacketSize0 != 0x40) {
413 		if (desc->bDeviceClass == 0x00 || desc->bDeviceClass == 0xff)
414 			return TYPE_H;	/* variant 1 */
415 
416 		return TYPE_H;		/* variant 0 */
417 	}
418 
419 	bcdDevice = le16_to_cpu(desc->bcdDevice);
420 	bcdUSB = le16_to_cpu(desc->bcdUSB);
421 
422 	switch (bcdUSB) {
423 	case 0x110:
424 		switch (bcdDevice) {
425 		case 0x300:
426 			return TYPE_HX;
427 		case 0x400:
428 			return TYPE_HXD;
429 		default:
430 			return TYPE_HX;
431 		}
432 		break;
433 	case 0x200:
434 		switch (bcdDevice) {
435 		case 0x100:
436 		case 0x105:
437 		case 0x305:
438 		case 0x405:
439 		case 0x605:
440 			/*
441 			 * Assume it's an HXN-type if the device doesn't
442 			 * support the old read request value.
443 			 */
444 			if (!pl2303_supports_hx_status(serial))
445 				return TYPE_HXN;
446 			break;
447 		case 0x300:
448 			return TYPE_TA;
449 		case 0x500:
450 			return TYPE_TB;
451 		}
452 		break;
453 	}
454 
455 	dev_err(&serial->interface->dev,
456 			"unknown device type, please report to linux-usb@vger.kernel.org\n");
457 	return -ENODEV;
458 }
459 
460 static int pl2303_startup(struct usb_serial *serial)
461 {
462 	struct pl2303_serial_private *spriv;
463 	enum pl2303_type type;
464 	unsigned char *buf;
465 	int ret;
466 
467 	ret = pl2303_detect_type(serial);
468 	if (ret < 0)
469 		return ret;
470 
471 	type = ret;
472 	dev_dbg(&serial->interface->dev, "device type: %s\n", pl2303_type_data[type].name);
473 
474 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
475 	if (!spriv)
476 		return -ENOMEM;
477 
478 	spriv->type = &pl2303_type_data[type];
479 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
480 	spriv->quirks |= spriv->type->quirks;
481 
482 	usb_set_serial_data(serial, spriv);
483 
484 	if (type != TYPE_HXN) {
485 		buf = kmalloc(1, GFP_KERNEL);
486 		if (!buf) {
487 			kfree(spriv);
488 			return -ENOMEM;
489 		}
490 
491 		pl2303_vendor_read(serial, 0x8484, buf);
492 		pl2303_vendor_write(serial, 0x0404, 0);
493 		pl2303_vendor_read(serial, 0x8484, buf);
494 		pl2303_vendor_read(serial, 0x8383, buf);
495 		pl2303_vendor_read(serial, 0x8484, buf);
496 		pl2303_vendor_write(serial, 0x0404, 1);
497 		pl2303_vendor_read(serial, 0x8484, buf);
498 		pl2303_vendor_read(serial, 0x8383, buf);
499 		pl2303_vendor_write(serial, 0, 1);
500 		pl2303_vendor_write(serial, 1, 0);
501 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
502 			pl2303_vendor_write(serial, 2, 0x24);
503 		else
504 			pl2303_vendor_write(serial, 2, 0x44);
505 
506 		kfree(buf);
507 	}
508 
509 	return 0;
510 }
511 
512 static void pl2303_release(struct usb_serial *serial)
513 {
514 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
515 
516 	kfree(spriv);
517 }
518 
519 static int pl2303_port_probe(struct usb_serial_port *port)
520 {
521 	struct pl2303_private *priv;
522 
523 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
524 	if (!priv)
525 		return -ENOMEM;
526 
527 	spin_lock_init(&priv->lock);
528 
529 	usb_set_serial_port_data(port, priv);
530 
531 	port->port.drain_delay = 256;
532 
533 	return 0;
534 }
535 
536 static void pl2303_port_remove(struct usb_serial_port *port)
537 {
538 	struct pl2303_private *priv = usb_get_serial_port_data(port);
539 
540 	kfree(priv);
541 }
542 
543 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
544 {
545 	struct usb_device *dev = port->serial->dev;
546 	int retval;
547 
548 	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
549 
550 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
551 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
552 				 value, 0, NULL, 0, 100);
553 	if (retval)
554 		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
555 
556 	return retval;
557 }
558 
559 /*
560  * Returns the nearest supported baud rate that can be set directly without
561  * using divisors.
562  */
563 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
564 {
565 	static const speed_t baud_sup[] = {
566 		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
567 		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
568 		614400, 921600, 1228800, 2457600, 3000000, 6000000
569 	};
570 
571 	unsigned i;
572 
573 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
574 		if (baud_sup[i] > baud)
575 			break;
576 	}
577 
578 	if (i == ARRAY_SIZE(baud_sup))
579 		baud = baud_sup[i - 1];
580 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
581 		baud = baud_sup[i - 1];
582 	else
583 		baud = baud_sup[i];
584 
585 	return baud;
586 }
587 
588 /*
589  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
590  *       use 9600 baud.
591  */
592 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
593 								speed_t baud)
594 {
595 	put_unaligned_le32(baud, buf);
596 
597 	return baud;
598 }
599 
600 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
601 								speed_t baud)
602 {
603 	unsigned int baseline, mantissa, exponent;
604 
605 	/*
606 	 * Apparently the formula is:
607 	 *   baudrate = 12M * 32 / (mantissa * 4^exponent)
608 	 * where
609 	 *   mantissa = buf[8:0]
610 	 *   exponent = buf[11:9]
611 	 */
612 	baseline = 12000000 * 32;
613 	mantissa = baseline / baud;
614 	if (mantissa == 0)
615 		mantissa = 1;	/* Avoid dividing by zero if baud > 32*12M. */
616 	exponent = 0;
617 	while (mantissa >= 512) {
618 		if (exponent < 7) {
619 			mantissa >>= 2;	/* divide by 4 */
620 			exponent++;
621 		} else {
622 			/* Exponent is maxed. Trim mantissa and leave. */
623 			mantissa = 511;
624 			break;
625 		}
626 	}
627 
628 	buf[3] = 0x80;
629 	buf[2] = 0;
630 	buf[1] = exponent << 1 | mantissa >> 8;
631 	buf[0] = mantissa & 0xff;
632 
633 	/* Calculate and return the exact baud rate. */
634 	baud = (baseline / mantissa) >> (exponent << 1);
635 
636 	return baud;
637 }
638 
639 static speed_t pl2303_encode_baud_rate_divisor_alt(unsigned char buf[4],
640 								speed_t baud)
641 {
642 	unsigned int baseline, mantissa, exponent;
643 
644 	/*
645 	 * Apparently, for the TA version the formula is:
646 	 *   baudrate = 12M * 32 / (mantissa * 2^exponent)
647 	 * where
648 	 *   mantissa = buf[10:0]
649 	 *   exponent = buf[15:13 16]
650 	 */
651 	baseline = 12000000 * 32;
652 	mantissa = baseline / baud;
653 	if (mantissa == 0)
654 		mantissa = 1;   /* Avoid dividing by zero if baud > 32*12M. */
655 	exponent = 0;
656 	while (mantissa >= 2048) {
657 		if (exponent < 15) {
658 			mantissa >>= 1; /* divide by 2 */
659 			exponent++;
660 		} else {
661 			/* Exponent is maxed. Trim mantissa and leave. */
662 			mantissa = 2047;
663 			break;
664 		}
665 	}
666 
667 	buf[3] = 0x80;
668 	buf[2] = exponent & 0x01;
669 	buf[1] = (exponent & ~0x01) << 4 | mantissa >> 8;
670 	buf[0] = mantissa & 0xff;
671 
672 	/* Calculate and return the exact baud rate. */
673 	baud = (baseline / mantissa) >> exponent;
674 
675 	return baud;
676 }
677 
678 static void pl2303_encode_baud_rate(struct tty_struct *tty,
679 					struct usb_serial_port *port,
680 					u8 buf[4])
681 {
682 	struct usb_serial *serial = port->serial;
683 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
684 	speed_t	baud_sup;
685 	speed_t baud;
686 
687 	baud = tty_get_baud_rate(tty);
688 	dev_dbg(&port->dev, "baud requested = %u\n", baud);
689 	if (!baud)
690 		return;
691 
692 	if (spriv->type->max_baud_rate)
693 		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
694 	/*
695 	 * Use direct method for supported baud rates, otherwise use divisors.
696 	 * Newer chip types do not support divisor encoding.
697 	 */
698 	if (spriv->type->no_divisors)
699 		baud_sup = baud;
700 	else
701 		baud_sup = pl2303_get_supported_baud_rate(baud);
702 
703 	if (baud == baud_sup)
704 		baud = pl2303_encode_baud_rate_direct(buf, baud);
705 	else if (spriv->type->alt_divisors)
706 		baud = pl2303_encode_baud_rate_divisor_alt(buf, baud);
707 	else
708 		baud = pl2303_encode_baud_rate_divisor(buf, baud);
709 
710 	/* Save resulting baud rate */
711 	tty_encode_baud_rate(tty, baud, baud);
712 	dev_dbg(&port->dev, "baud set = %u\n", baud);
713 }
714 
715 static int pl2303_get_line_request(struct usb_serial_port *port,
716 							unsigned char buf[7])
717 {
718 	struct usb_device *udev = port->serial->dev;
719 	int ret;
720 
721 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
722 				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
723 				0, 0, buf, 7, 100);
724 	if (ret != 7) {
725 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
726 
727 		if (ret >= 0)
728 			ret = -EIO;
729 
730 		return ret;
731 	}
732 
733 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
734 
735 	return 0;
736 }
737 
738 static int pl2303_set_line_request(struct usb_serial_port *port,
739 							unsigned char buf[7])
740 {
741 	struct usb_device *udev = port->serial->dev;
742 	int ret;
743 
744 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
745 				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
746 				0, 0, buf, 7, 100);
747 	if (ret < 0) {
748 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
749 		return ret;
750 	}
751 
752 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
753 
754 	return 0;
755 }
756 
757 static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
758 {
759 	bool ixon_change;
760 
761 	ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
762 			a->c_cc[VSTART] != b->c_cc[VSTART] ||
763 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
764 
765 	return tty_termios_hw_change(a, b) || ixon_change;
766 }
767 
768 static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
769 {
770 	if (!I_IXON(tty) || I_IXANY(tty))
771 		return false;
772 
773 	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
774 		return false;
775 
776 	if (type->no_autoxonxoff)
777 		return false;
778 
779 	return true;
780 }
781 
782 static void pl2303_set_termios(struct tty_struct *tty,
783 		struct usb_serial_port *port, struct ktermios *old_termios)
784 {
785 	struct usb_serial *serial = port->serial;
786 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
787 	struct pl2303_private *priv = usb_get_serial_port_data(port);
788 	unsigned long flags;
789 	unsigned char *buf;
790 	int ret;
791 	u8 control;
792 
793 	if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
794 		return;
795 
796 	buf = kzalloc(7, GFP_KERNEL);
797 	if (!buf) {
798 		/* Report back no change occurred */
799 		if (old_termios)
800 			tty->termios = *old_termios;
801 		return;
802 	}
803 
804 	pl2303_get_line_request(port, buf);
805 
806 	buf[6] = tty_get_char_size(tty->termios.c_cflag);
807 	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
808 
809 	/* For reference buf[0]:buf[3] baud rate value */
810 	pl2303_encode_baud_rate(tty, port, &buf[0]);
811 
812 	/* For reference buf[4]=0 is 1 stop bits */
813 	/* For reference buf[4]=1 is 1.5 stop bits */
814 	/* For reference buf[4]=2 is 2 stop bits */
815 	if (C_CSTOPB(tty)) {
816 		/*
817 		 * NOTE: Comply with "real" UARTs / RS232:
818 		 *       use 1.5 instead of 2 stop bits with 5 data bits
819 		 */
820 		if (C_CSIZE(tty) == CS5) {
821 			buf[4] = 1;
822 			dev_dbg(&port->dev, "stop bits = 1.5\n");
823 		} else {
824 			buf[4] = 2;
825 			dev_dbg(&port->dev, "stop bits = 2\n");
826 		}
827 	} else {
828 		buf[4] = 0;
829 		dev_dbg(&port->dev, "stop bits = 1\n");
830 	}
831 
832 	if (C_PARENB(tty)) {
833 		/* For reference buf[5]=0 is none parity */
834 		/* For reference buf[5]=1 is odd parity */
835 		/* For reference buf[5]=2 is even parity */
836 		/* For reference buf[5]=3 is mark parity */
837 		/* For reference buf[5]=4 is space parity */
838 		if (C_PARODD(tty)) {
839 			if (C_CMSPAR(tty)) {
840 				buf[5] = 3;
841 				dev_dbg(&port->dev, "parity = mark\n");
842 			} else {
843 				buf[5] = 1;
844 				dev_dbg(&port->dev, "parity = odd\n");
845 			}
846 		} else {
847 			if (C_CMSPAR(tty)) {
848 				buf[5] = 4;
849 				dev_dbg(&port->dev, "parity = space\n");
850 			} else {
851 				buf[5] = 2;
852 				dev_dbg(&port->dev, "parity = even\n");
853 			}
854 		}
855 	} else {
856 		buf[5] = 0;
857 		dev_dbg(&port->dev, "parity = none\n");
858 	}
859 
860 	/*
861 	 * Some PL2303 are known to lose bytes if you change serial settings
862 	 * even to the same values as before. Thus we actually need to filter
863 	 * in this specific case.
864 	 *
865 	 * Note that the tty_termios_hw_change check above is not sufficient
866 	 * as a previously requested baud rate may differ from the one
867 	 * actually used (and stored in old_termios).
868 	 *
869 	 * NOTE: No additional locking needed for line_settings as it is
870 	 *       only used in set_termios, which is serialised against itself.
871 	 */
872 	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
873 		ret = pl2303_set_line_request(port, buf);
874 		if (!ret)
875 			memcpy(priv->line_settings, buf, 7);
876 	}
877 
878 	/* change control lines if we are switching to or from B0 */
879 	spin_lock_irqsave(&priv->lock, flags);
880 	control = priv->line_control;
881 	if (C_BAUD(tty) == B0)
882 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
883 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
884 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
885 	if (control != priv->line_control) {
886 		control = priv->line_control;
887 		spin_unlock_irqrestore(&priv->lock, flags);
888 		pl2303_set_control_lines(port, control);
889 	} else {
890 		spin_unlock_irqrestore(&priv->lock, flags);
891 	}
892 
893 	if (C_CRTSCTS(tty)) {
894 		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
895 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
896 		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
897 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
898 					PL2303_HXN_FLOWCTRL_MASK,
899 					PL2303_HXN_FLOWCTRL_RTS_CTS);
900 		} else {
901 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
902 		}
903 	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
904 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
905 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
906 					PL2303_HXN_FLOWCTRL_MASK,
907 					PL2303_HXN_FLOWCTRL_XON_XOFF);
908 		} else {
909 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
910 		}
911 	} else {
912 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
913 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
914 					PL2303_HXN_FLOWCTRL_MASK,
915 					PL2303_HXN_FLOWCTRL_NONE);
916 		} else {
917 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
918 		}
919 	}
920 
921 	kfree(buf);
922 }
923 
924 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
925 {
926 	struct pl2303_private *priv = usb_get_serial_port_data(port);
927 	unsigned long flags;
928 	u8 control;
929 
930 	spin_lock_irqsave(&priv->lock, flags);
931 	if (on)
932 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
933 	else
934 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
935 	control = priv->line_control;
936 	spin_unlock_irqrestore(&priv->lock, flags);
937 
938 	pl2303_set_control_lines(port, control);
939 }
940 
941 static void pl2303_close(struct usb_serial_port *port)
942 {
943 	usb_serial_generic_close(port);
944 	usb_kill_urb(port->interrupt_in_urb);
945 	pl2303_set_break(port, false);
946 }
947 
948 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
949 {
950 	struct usb_serial *serial = port->serial;
951 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
952 	int result;
953 
954 	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
955 		usb_clear_halt(serial->dev, port->write_urb->pipe);
956 		usb_clear_halt(serial->dev, port->read_urb->pipe);
957 	} else {
958 		/* reset upstream data pipes */
959 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
960 			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
961 					PL2303_HXN_RESET_UPSTREAM_PIPE |
962 					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
963 		} else {
964 			pl2303_vendor_write(serial, 8, 0);
965 			pl2303_vendor_write(serial, 9, 0);
966 		}
967 	}
968 
969 	/* Setup termios */
970 	if (tty)
971 		pl2303_set_termios(tty, port, NULL);
972 
973 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
974 	if (result) {
975 		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
976 			result);
977 		return result;
978 	}
979 
980 	result = usb_serial_generic_open(tty, port);
981 	if (result) {
982 		usb_kill_urb(port->interrupt_in_urb);
983 		return result;
984 	}
985 
986 	return 0;
987 }
988 
989 static int pl2303_tiocmset(struct tty_struct *tty,
990 			   unsigned int set, unsigned int clear)
991 {
992 	struct usb_serial_port *port = tty->driver_data;
993 	struct pl2303_private *priv = usb_get_serial_port_data(port);
994 	unsigned long flags;
995 	u8 control;
996 	int ret;
997 
998 	spin_lock_irqsave(&priv->lock, flags);
999 	if (set & TIOCM_RTS)
1000 		priv->line_control |= CONTROL_RTS;
1001 	if (set & TIOCM_DTR)
1002 		priv->line_control |= CONTROL_DTR;
1003 	if (clear & TIOCM_RTS)
1004 		priv->line_control &= ~CONTROL_RTS;
1005 	if (clear & TIOCM_DTR)
1006 		priv->line_control &= ~CONTROL_DTR;
1007 	control = priv->line_control;
1008 	spin_unlock_irqrestore(&priv->lock, flags);
1009 
1010 	ret = pl2303_set_control_lines(port, control);
1011 	if (ret)
1012 		return usb_translate_errors(ret);
1013 
1014 	return 0;
1015 }
1016 
1017 static int pl2303_tiocmget(struct tty_struct *tty)
1018 {
1019 	struct usb_serial_port *port = tty->driver_data;
1020 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1021 	unsigned long flags;
1022 	unsigned int mcr;
1023 	unsigned int status;
1024 	unsigned int result;
1025 
1026 	spin_lock_irqsave(&priv->lock, flags);
1027 	mcr = priv->line_control;
1028 	status = priv->line_status;
1029 	spin_unlock_irqrestore(&priv->lock, flags);
1030 
1031 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
1032 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
1033 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
1034 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
1035 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
1036 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
1037 
1038 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
1039 
1040 	return result;
1041 }
1042 
1043 static int pl2303_carrier_raised(struct usb_serial_port *port)
1044 {
1045 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1046 
1047 	if (priv->line_status & UART_DCD)
1048 		return 1;
1049 
1050 	return 0;
1051 }
1052 
1053 static void pl2303_set_break(struct usb_serial_port *port, bool enable)
1054 {
1055 	struct usb_serial *serial = port->serial;
1056 	u16 state;
1057 	int result;
1058 
1059 	if (enable)
1060 		state = BREAK_ON;
1061 	else
1062 		state = BREAK_OFF;
1063 
1064 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1065 			state == BREAK_OFF ? "off" : "on");
1066 
1067 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1068 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
1069 				 0, NULL, 0, 100);
1070 	if (result)
1071 		dev_err(&port->dev, "error sending break = %d\n", result);
1072 }
1073 
1074 static void pl2303_break_ctl(struct tty_struct *tty, int state)
1075 {
1076 	struct usb_serial_port *port = tty->driver_data;
1077 
1078 	pl2303_set_break(port, state);
1079 }
1080 
1081 static void pl2303_update_line_status(struct usb_serial_port *port,
1082 				      unsigned char *data,
1083 				      unsigned int actual_length)
1084 {
1085 	struct usb_serial *serial = port->serial;
1086 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
1087 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1088 	struct tty_struct *tty;
1089 	unsigned long flags;
1090 	unsigned int status_idx = UART_STATE_INDEX;
1091 	u8 status;
1092 	u8 delta;
1093 
1094 	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
1095 		status_idx = 0;
1096 
1097 	if (actual_length < status_idx + 1)
1098 		return;
1099 
1100 	status = data[status_idx];
1101 
1102 	/* Save off the uart status for others to look at */
1103 	spin_lock_irqsave(&priv->lock, flags);
1104 	delta = priv->line_status ^ status;
1105 	priv->line_status = status;
1106 	spin_unlock_irqrestore(&priv->lock, flags);
1107 
1108 	if (status & UART_BREAK_ERROR)
1109 		usb_serial_handle_break(port);
1110 
1111 	if (delta & UART_STATE_MSR_MASK) {
1112 		if (delta & UART_CTS)
1113 			port->icount.cts++;
1114 		if (delta & UART_DSR)
1115 			port->icount.dsr++;
1116 		if (delta & UART_RING)
1117 			port->icount.rng++;
1118 		if (delta & UART_DCD) {
1119 			port->icount.dcd++;
1120 			tty = tty_port_tty_get(&port->port);
1121 			if (tty) {
1122 				usb_serial_handle_dcd_change(port, tty,
1123 							status & UART_DCD);
1124 				tty_kref_put(tty);
1125 			}
1126 		}
1127 
1128 		wake_up_interruptible(&port->port.delta_msr_wait);
1129 	}
1130 }
1131 
1132 static void pl2303_read_int_callback(struct urb *urb)
1133 {
1134 	struct usb_serial_port *port =  urb->context;
1135 	unsigned char *data = urb->transfer_buffer;
1136 	unsigned int actual_length = urb->actual_length;
1137 	int status = urb->status;
1138 	int retval;
1139 
1140 	switch (status) {
1141 	case 0:
1142 		/* success */
1143 		break;
1144 	case -ECONNRESET:
1145 	case -ENOENT:
1146 	case -ESHUTDOWN:
1147 		/* this urb is terminated, clean up */
1148 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1149 			__func__, status);
1150 		return;
1151 	default:
1152 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1153 			__func__, status);
1154 		goto exit;
1155 	}
1156 
1157 	usb_serial_debug_data(&port->dev, __func__,
1158 			      urb->actual_length, urb->transfer_buffer);
1159 
1160 	pl2303_update_line_status(port, data, actual_length);
1161 
1162 exit:
1163 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1164 	if (retval) {
1165 		dev_err(&port->dev,
1166 			"%s - usb_submit_urb failed with result %d\n",
1167 			__func__, retval);
1168 	}
1169 }
1170 
1171 static void pl2303_process_read_urb(struct urb *urb)
1172 {
1173 	struct usb_serial_port *port = urb->context;
1174 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1175 	unsigned char *data = urb->transfer_buffer;
1176 	char tty_flag = TTY_NORMAL;
1177 	unsigned long flags;
1178 	u8 line_status;
1179 	int i;
1180 
1181 	/* update line status */
1182 	spin_lock_irqsave(&priv->lock, flags);
1183 	line_status = priv->line_status;
1184 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1185 	spin_unlock_irqrestore(&priv->lock, flags);
1186 
1187 	if (!urb->actual_length)
1188 		return;
1189 
1190 	/*
1191 	 * Break takes precedence over parity, which takes precedence over
1192 	 * framing errors.
1193 	 */
1194 	if (line_status & UART_BREAK_ERROR)
1195 		tty_flag = TTY_BREAK;
1196 	else if (line_status & UART_PARITY_ERROR)
1197 		tty_flag = TTY_PARITY;
1198 	else if (line_status & UART_FRAME_ERROR)
1199 		tty_flag = TTY_FRAME;
1200 
1201 	if (tty_flag != TTY_NORMAL)
1202 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1203 								tty_flag);
1204 	/* overrun is special, not associated with a char */
1205 	if (line_status & UART_OVERRUN_ERROR)
1206 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1207 
1208 	if (port->sysrq) {
1209 		for (i = 0; i < urb->actual_length; ++i)
1210 			if (!usb_serial_handle_sysrq_char(port, data[i]))
1211 				tty_insert_flip_char(&port->port, data[i],
1212 						tty_flag);
1213 	} else {
1214 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1215 							urb->actual_length);
1216 	}
1217 
1218 	tty_flip_buffer_push(&port->port);
1219 }
1220 
1221 static struct usb_serial_driver pl2303_device = {
1222 	.driver = {
1223 		.owner =	THIS_MODULE,
1224 		.name =		"pl2303",
1225 	},
1226 	.id_table =		id_table,
1227 	.num_bulk_in =		1,
1228 	.num_bulk_out =		1,
1229 	.num_interrupt_in =	0,	/* see pl2303_calc_num_ports */
1230 	.bulk_in_size =		256,
1231 	.bulk_out_size =	256,
1232 	.open =			pl2303_open,
1233 	.close =		pl2303_close,
1234 	.dtr_rts =		pl2303_dtr_rts,
1235 	.carrier_raised =	pl2303_carrier_raised,
1236 	.break_ctl =		pl2303_break_ctl,
1237 	.set_termios =		pl2303_set_termios,
1238 	.tiocmget =		pl2303_tiocmget,
1239 	.tiocmset =		pl2303_tiocmset,
1240 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
1241 	.process_read_urb =	pl2303_process_read_urb,
1242 	.read_int_callback =	pl2303_read_int_callback,
1243 	.probe =		pl2303_probe,
1244 	.calc_num_ports =	pl2303_calc_num_ports,
1245 	.attach =		pl2303_startup,
1246 	.release =		pl2303_release,
1247 	.port_probe =		pl2303_port_probe,
1248 	.port_remove =		pl2303_port_remove,
1249 };
1250 
1251 static struct usb_serial_driver * const serial_drivers[] = {
1252 	&pl2303_device, NULL
1253 };
1254 
1255 module_usb_serial_driver(serial_drivers, id_table);
1256 
1257 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1258 MODULE_LICENSE("GPL v2");
1259