xref: /linux/drivers/usb/serial/pl2303.c (revision 63c3a1a9be06f8f8c75d54ef9331e35adb2e7919)
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_flip.h>
19 #include <linux/serial.h>
20 #include <linux/module.h>
21 #include <linux/spinlock.h>
22 #include <linux/usb.h>
23 #include <linux/usb/serial.h>
24 #include <linux/unaligned.h>
25 #include "pl2303.h"
26 
27 
28 #define PL2303_QUIRK_UART_STATE_IDX0		BIT(0)
29 #define PL2303_QUIRK_LEGACY			BIT(1)
30 #define PL2303_QUIRK_ENDPOINT_HACK		BIT(2)
31 #define PL2303_QUIRK_NO_BREAK_GETLINE		BIT(3)
32 
33 static const struct usb_device_id id_table[] = {
34 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID),
35 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
36 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
37 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
38 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
39 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_CHILITAG) },
40 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
41 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
42 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
43 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
44 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
45 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
46 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ZTEK) },
47 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_TB) },
48 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GC) },
49 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GB) },
50 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GT) },
51 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GL) },
52 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GE) },
53 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GS) },
54 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
55 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
56 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID),
57 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
58 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC485),
59 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
60 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC232B),
61 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
62 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID2) },
63 	{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
64 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
65 	{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
66 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
67 	{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
68 	{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
69 	{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
70 	{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
71 	{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
72 	{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
73 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
74 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
75 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
76 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
77 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
78 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
79 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
80 		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
81 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81),
82 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
83 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
84 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
85 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
86 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
87 	{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
88 	{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
89 	{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
90 	{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
91 	{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
92 	{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID),
93 		.driver_info = PL2303_QUIRK_ENDPOINT_HACK },
94 	{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
95 	{ USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
96 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
97 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
98 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
99 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220TA_PRODUCT_ID) },
100 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD381_PRODUCT_ID) },
101 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD381GC_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_LM930_PRODUCT_ID) },
108 	{ USB_DEVICE(HP_VENDOR_ID, HP_LM940_PRODUCT_ID) },
109 	{ USB_DEVICE(HP_VENDOR_ID, HP_TD620_PRODUCT_ID) },
110 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
111 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
112 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
113 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
114 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
115 	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530GC_PRODUCT_ID) },
116 	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
117 	{ USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
118 	{ USB_DEVICE(IBM_VENDOR_ID, IBM_PRODUCT_ID) },
119 	{ USB_DEVICE(MACROSILICON_VENDOR_ID, MACROSILICON_MS3020_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 int 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 0x101:
424 		/* USB 1.0.1? Let's assume they meant 1.1... */
425 		fallthrough;
426 	case 0x110:
427 		switch (bcdDevice) {
428 		case 0x300:
429 			return TYPE_HX;
430 		case 0x400:
431 			return TYPE_HXD;
432 		default:
433 			return TYPE_HX;
434 		}
435 		break;
436 	case 0x200:
437 		switch (bcdDevice) {
438 		case 0x100:	/* GC */
439 		case 0x105:
440 			return TYPE_HXN;
441 		case 0x300:	/* GT / TA */
442 			if (pl2303_supports_hx_status(serial))
443 				return TYPE_TA;
444 			fallthrough;
445 		case 0x305:
446 		case 0x400:	/* GL */
447 		case 0x405:
448 			return TYPE_HXN;
449 		case 0x500:	/* GE / TB */
450 			if (pl2303_supports_hx_status(serial))
451 				return TYPE_TB;
452 			fallthrough;
453 		case 0x505:
454 		case 0x600:	/* GS */
455 		case 0x605:
456 		case 0x700:	/* GR */
457 		case 0x705:
458 		case 0x905:	/* GT-2AB */
459 		case 0x1005:	/* GC-Q20 */
460 			return TYPE_HXN;
461 		}
462 		break;
463 	}
464 
465 	dev_err(&serial->interface->dev,
466 			"unknown device type, please report to linux-usb@vger.kernel.org\n");
467 	return -ENODEV;
468 }
469 
470 static bool pl2303_is_hxd_clone(struct usb_serial *serial)
471 {
472 	struct usb_device *udev = serial->dev;
473 	unsigned char *buf;
474 	int ret;
475 
476 	buf = kmalloc(7, GFP_KERNEL);
477 	if (!buf)
478 		return false;
479 
480 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
481 			      GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
482 			      0, 0, buf, 7, 100);
483 
484 	kfree(buf);
485 
486 	return ret == -EPIPE;
487 }
488 
489 static int pl2303_startup(struct usb_serial *serial)
490 {
491 	struct pl2303_serial_private *spriv;
492 	enum pl2303_type type;
493 	unsigned char *buf;
494 	int ret;
495 
496 	ret = pl2303_detect_type(serial);
497 	if (ret < 0)
498 		return ret;
499 
500 	type = ret;
501 	dev_dbg(&serial->interface->dev, "device type: %s\n", pl2303_type_data[type].name);
502 
503 	spriv = kzalloc_obj(*spriv);
504 	if (!spriv)
505 		return -ENOMEM;
506 
507 	spriv->type = &pl2303_type_data[type];
508 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
509 	spriv->quirks |= spriv->type->quirks;
510 
511 	if (type == TYPE_HXD && pl2303_is_hxd_clone(serial))
512 		spriv->quirks |= PL2303_QUIRK_NO_BREAK_GETLINE;
513 
514 	usb_set_serial_data(serial, spriv);
515 
516 	if (type != TYPE_HXN) {
517 		buf = kmalloc(1, GFP_KERNEL);
518 		if (!buf) {
519 			kfree(spriv);
520 			return -ENOMEM;
521 		}
522 
523 		pl2303_vendor_read(serial, 0x8484, buf);
524 		pl2303_vendor_write(serial, 0x0404, 0);
525 		pl2303_vendor_read(serial, 0x8484, buf);
526 		pl2303_vendor_read(serial, 0x8383, buf);
527 		pl2303_vendor_read(serial, 0x8484, buf);
528 		pl2303_vendor_write(serial, 0x0404, 1);
529 		pl2303_vendor_read(serial, 0x8484, buf);
530 		pl2303_vendor_read(serial, 0x8383, buf);
531 		pl2303_vendor_write(serial, 0, 1);
532 		pl2303_vendor_write(serial, 1, 0);
533 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
534 			pl2303_vendor_write(serial, 2, 0x24);
535 		else
536 			pl2303_vendor_write(serial, 2, 0x44);
537 
538 		kfree(buf);
539 	}
540 
541 	return 0;
542 }
543 
544 static void pl2303_release(struct usb_serial *serial)
545 {
546 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
547 
548 	kfree(spriv);
549 }
550 
551 static int pl2303_port_probe(struct usb_serial_port *port)
552 {
553 	struct pl2303_private *priv;
554 
555 	priv = kzalloc_obj(*priv);
556 	if (!priv)
557 		return -ENOMEM;
558 
559 	spin_lock_init(&priv->lock);
560 
561 	usb_set_serial_port_data(port, priv);
562 
563 	port->port.drain_delay = 256;
564 
565 	return 0;
566 }
567 
568 static void pl2303_port_remove(struct usb_serial_port *port)
569 {
570 	struct pl2303_private *priv = usb_get_serial_port_data(port);
571 
572 	kfree(priv);
573 }
574 
575 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
576 {
577 	struct usb_device *dev = port->serial->dev;
578 	int retval;
579 
580 	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
581 
582 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
583 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
584 				 value, 0, NULL, 0, 100);
585 	if (retval)
586 		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
587 
588 	return retval;
589 }
590 
591 /*
592  * Returns the nearest supported baud rate that can be set directly without
593  * using divisors.
594  */
595 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
596 {
597 	static const speed_t baud_sup[] = {
598 		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
599 		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
600 		614400, 921600, 1228800, 2457600, 3000000, 6000000
601 	};
602 
603 	unsigned i;
604 
605 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
606 		if (baud_sup[i] > baud)
607 			break;
608 	}
609 
610 	if (i == ARRAY_SIZE(baud_sup))
611 		baud = baud_sup[i - 1];
612 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
613 		baud = baud_sup[i - 1];
614 	else
615 		baud = baud_sup[i];
616 
617 	return baud;
618 }
619 
620 /*
621  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
622  *       use 9600 baud.
623  */
624 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
625 								speed_t baud)
626 {
627 	put_unaligned_le32(baud, buf);
628 
629 	return baud;
630 }
631 
632 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
633 								speed_t baud)
634 {
635 	unsigned int baseline, mantissa, exponent;
636 
637 	/*
638 	 * Apparently the formula is:
639 	 *   baudrate = 12M * 32 / (mantissa * 4^exponent)
640 	 * where
641 	 *   mantissa = buf[8:0]
642 	 *   exponent = buf[11:9]
643 	 */
644 	baseline = 12000000 * 32;
645 	mantissa = baseline / baud;
646 	if (mantissa == 0)
647 		mantissa = 1;	/* Avoid dividing by zero if baud > 32*12M. */
648 	exponent = 0;
649 	while (mantissa >= 512) {
650 		if (exponent < 7) {
651 			mantissa >>= 2;	/* divide by 4 */
652 			exponent++;
653 		} else {
654 			/* Exponent is maxed. Trim mantissa and leave. */
655 			mantissa = 511;
656 			break;
657 		}
658 	}
659 
660 	buf[3] = 0x80;
661 	buf[2] = 0;
662 	buf[1] = exponent << 1 | mantissa >> 8;
663 	buf[0] = mantissa & 0xff;
664 
665 	/* Calculate and return the exact baud rate. */
666 	baud = (baseline / mantissa) >> (exponent << 1);
667 
668 	return baud;
669 }
670 
671 static speed_t pl2303_encode_baud_rate_divisor_alt(unsigned char buf[4],
672 								speed_t baud)
673 {
674 	unsigned int baseline, mantissa, exponent;
675 
676 	/*
677 	 * Apparently, for the TA version the formula is:
678 	 *   baudrate = 12M * 32 / (mantissa * 2^exponent)
679 	 * where
680 	 *   mantissa = buf[10:0]
681 	 *   exponent = buf[15:13 16]
682 	 */
683 	baseline = 12000000 * 32;
684 	mantissa = baseline / baud;
685 	if (mantissa == 0)
686 		mantissa = 1;   /* Avoid dividing by zero if baud > 32*12M. */
687 	exponent = 0;
688 	while (mantissa >= 2048) {
689 		if (exponent < 15) {
690 			mantissa >>= 1; /* divide by 2 */
691 			exponent++;
692 		} else {
693 			/* Exponent is maxed. Trim mantissa and leave. */
694 			mantissa = 2047;
695 			break;
696 		}
697 	}
698 
699 	buf[3] = 0x80;
700 	buf[2] = exponent & 0x01;
701 	buf[1] = (exponent & ~0x01) << 4 | mantissa >> 8;
702 	buf[0] = mantissa & 0xff;
703 
704 	/* Calculate and return the exact baud rate. */
705 	baud = (baseline / mantissa) >> exponent;
706 
707 	return baud;
708 }
709 
710 static void pl2303_encode_baud_rate(struct tty_struct *tty,
711 					struct usb_serial_port *port,
712 					u8 buf[4])
713 {
714 	struct usb_serial *serial = port->serial;
715 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
716 	speed_t	baud_sup;
717 	speed_t baud;
718 
719 	baud = tty_get_baud_rate(tty);
720 	dev_dbg(&port->dev, "baud requested = %u\n", baud);
721 	if (!baud)
722 		return;
723 
724 	if (spriv->type->max_baud_rate)
725 		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
726 	/*
727 	 * Use direct method for supported baud rates, otherwise use divisors.
728 	 * Newer chip types do not support divisor encoding.
729 	 */
730 	if (spriv->type->no_divisors)
731 		baud_sup = baud;
732 	else
733 		baud_sup = pl2303_get_supported_baud_rate(baud);
734 
735 	if (baud == baud_sup)
736 		baud = pl2303_encode_baud_rate_direct(buf, baud);
737 	else if (spriv->type->alt_divisors)
738 		baud = pl2303_encode_baud_rate_divisor_alt(buf, baud);
739 	else
740 		baud = pl2303_encode_baud_rate_divisor(buf, baud);
741 
742 	/* Save resulting baud rate */
743 	tty_encode_baud_rate(tty, baud, baud);
744 	dev_dbg(&port->dev, "baud set = %u\n", baud);
745 }
746 
747 static int pl2303_get_line_request(struct usb_serial_port *port,
748 							unsigned char buf[7])
749 {
750 	struct usb_serial *serial = port->serial;
751 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
752 	struct usb_device *udev = serial->dev;
753 	int ret;
754 
755 	if (spriv->quirks & PL2303_QUIRK_NO_BREAK_GETLINE) {
756 		struct pl2303_private *priv = usb_get_serial_port_data(port);
757 
758 		memcpy(buf, priv->line_settings, 7);
759 		return 0;
760 	}
761 
762 	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
763 				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
764 				0, 0, buf, 7, 100);
765 	if (ret != 7) {
766 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
767 
768 		if (ret >= 0)
769 			ret = -EIO;
770 
771 		return ret;
772 	}
773 
774 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
775 
776 	return 0;
777 }
778 
779 static int pl2303_set_line_request(struct usb_serial_port *port,
780 							unsigned char buf[7])
781 {
782 	struct usb_device *udev = port->serial->dev;
783 	int ret;
784 
785 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
786 				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
787 				0, 0, buf, 7, 100);
788 	if (ret < 0) {
789 		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
790 		return ret;
791 	}
792 
793 	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
794 
795 	return 0;
796 }
797 
798 static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
799 {
800 	bool ixon_change;
801 
802 	ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
803 			a->c_cc[VSTART] != b->c_cc[VSTART] ||
804 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
805 
806 	return tty_termios_hw_change(a, b) || ixon_change;
807 }
808 
809 static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
810 {
811 	if (!I_IXON(tty) || I_IXANY(tty))
812 		return false;
813 
814 	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
815 		return false;
816 
817 	if (type->no_autoxonxoff)
818 		return false;
819 
820 	return true;
821 }
822 
823 static void pl2303_set_termios(struct tty_struct *tty,
824 			       struct usb_serial_port *port,
825 			       const struct ktermios *old_termios)
826 {
827 	struct usb_serial *serial = port->serial;
828 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
829 	struct pl2303_private *priv = usb_get_serial_port_data(port);
830 	unsigned long flags;
831 	unsigned char *buf;
832 	int ret;
833 	u8 control;
834 
835 	if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
836 		return;
837 
838 	buf = kzalloc(7, GFP_KERNEL);
839 	if (!buf) {
840 		/* Report back no change occurred */
841 		if (old_termios)
842 			tty->termios = *old_termios;
843 		return;
844 	}
845 
846 	pl2303_get_line_request(port, buf);
847 
848 	buf[6] = tty_get_char_size(tty->termios.c_cflag);
849 	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
850 
851 	/* For reference buf[0]:buf[3] baud rate value */
852 	pl2303_encode_baud_rate(tty, port, &buf[0]);
853 
854 	/* For reference buf[4]=0 is 1 stop bits */
855 	/* For reference buf[4]=1 is 1.5 stop bits */
856 	/* For reference buf[4]=2 is 2 stop bits */
857 	if (C_CSTOPB(tty)) {
858 		/*
859 		 * NOTE: Comply with "real" UARTs / RS232:
860 		 *       use 1.5 instead of 2 stop bits with 5 data bits
861 		 */
862 		if (C_CSIZE(tty) == CS5) {
863 			buf[4] = 1;
864 			dev_dbg(&port->dev, "stop bits = 1.5\n");
865 		} else {
866 			buf[4] = 2;
867 			dev_dbg(&port->dev, "stop bits = 2\n");
868 		}
869 	} else {
870 		buf[4] = 0;
871 		dev_dbg(&port->dev, "stop bits = 1\n");
872 	}
873 
874 	if (C_PARENB(tty)) {
875 		/* For reference buf[5]=0 is none parity */
876 		/* For reference buf[5]=1 is odd parity */
877 		/* For reference buf[5]=2 is even parity */
878 		/* For reference buf[5]=3 is mark parity */
879 		/* For reference buf[5]=4 is space parity */
880 		if (C_PARODD(tty)) {
881 			if (C_CMSPAR(tty)) {
882 				buf[5] = 3;
883 				dev_dbg(&port->dev, "parity = mark\n");
884 			} else {
885 				buf[5] = 1;
886 				dev_dbg(&port->dev, "parity = odd\n");
887 			}
888 		} else {
889 			if (C_CMSPAR(tty)) {
890 				buf[5] = 4;
891 				dev_dbg(&port->dev, "parity = space\n");
892 			} else {
893 				buf[5] = 2;
894 				dev_dbg(&port->dev, "parity = even\n");
895 			}
896 		}
897 	} else {
898 		buf[5] = 0;
899 		dev_dbg(&port->dev, "parity = none\n");
900 	}
901 
902 	/*
903 	 * Some PL2303 are known to lose bytes if you change serial settings
904 	 * even to the same values as before. Thus we actually need to filter
905 	 * in this specific case.
906 	 *
907 	 * Note that the tty_termios_hw_change check above is not sufficient
908 	 * as a previously requested baud rate may differ from the one
909 	 * actually used (and stored in old_termios).
910 	 *
911 	 * NOTE: No additional locking needed for line_settings as it is
912 	 *       only used in set_termios, which is serialised against itself.
913 	 */
914 	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
915 		ret = pl2303_set_line_request(port, buf);
916 		if (!ret)
917 			memcpy(priv->line_settings, buf, 7);
918 	}
919 
920 	/* change control lines if we are switching to or from B0 */
921 	spin_lock_irqsave(&priv->lock, flags);
922 	control = priv->line_control;
923 	if (C_BAUD(tty) == B0)
924 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
925 	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
926 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
927 	if (control != priv->line_control) {
928 		control = priv->line_control;
929 		spin_unlock_irqrestore(&priv->lock, flags);
930 		pl2303_set_control_lines(port, control);
931 	} else {
932 		spin_unlock_irqrestore(&priv->lock, flags);
933 	}
934 
935 	if (C_CRTSCTS(tty)) {
936 		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
937 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
938 		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
939 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
940 					PL2303_HXN_FLOWCTRL_MASK,
941 					PL2303_HXN_FLOWCTRL_RTS_CTS);
942 		} else {
943 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
944 		}
945 	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
946 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
947 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
948 					PL2303_HXN_FLOWCTRL_MASK,
949 					PL2303_HXN_FLOWCTRL_XON_XOFF);
950 		} else {
951 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
952 		}
953 	} else {
954 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
955 			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
956 					PL2303_HXN_FLOWCTRL_MASK,
957 					PL2303_HXN_FLOWCTRL_NONE);
958 		} else {
959 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
960 		}
961 	}
962 
963 	kfree(buf);
964 }
965 
966 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
967 {
968 	struct pl2303_private *priv = usb_get_serial_port_data(port);
969 	unsigned long flags;
970 	u8 control;
971 
972 	spin_lock_irqsave(&priv->lock, flags);
973 	if (on)
974 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
975 	else
976 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
977 	control = priv->line_control;
978 	spin_unlock_irqrestore(&priv->lock, flags);
979 
980 	pl2303_set_control_lines(port, control);
981 }
982 
983 static void pl2303_close(struct usb_serial_port *port)
984 {
985 	usb_serial_generic_close(port);
986 	usb_kill_urb(port->interrupt_in_urb);
987 	pl2303_set_break(port, false);
988 }
989 
990 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
991 {
992 	struct usb_serial *serial = port->serial;
993 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
994 	int result;
995 
996 	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
997 		usb_clear_halt(serial->dev, port->write_urb->pipe);
998 		usb_clear_halt(serial->dev, port->read_urb->pipe);
999 	} else {
1000 		/* reset upstream data pipes */
1001 		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
1002 			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
1003 					PL2303_HXN_RESET_UPSTREAM_PIPE |
1004 					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
1005 		} else {
1006 			pl2303_vendor_write(serial, 8, 0);
1007 			pl2303_vendor_write(serial, 9, 0);
1008 		}
1009 	}
1010 
1011 	/* Setup termios */
1012 	if (tty)
1013 		pl2303_set_termios(tty, port, NULL);
1014 
1015 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1016 	if (result) {
1017 		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
1018 			result);
1019 		return result;
1020 	}
1021 
1022 	result = usb_serial_generic_open(tty, port);
1023 	if (result) {
1024 		usb_kill_urb(port->interrupt_in_urb);
1025 		return result;
1026 	}
1027 
1028 	return 0;
1029 }
1030 
1031 static int pl2303_tiocmset(struct tty_struct *tty,
1032 			   unsigned int set, unsigned int clear)
1033 {
1034 	struct usb_serial_port *port = tty->driver_data;
1035 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1036 	unsigned long flags;
1037 	u8 control;
1038 	int ret;
1039 
1040 	spin_lock_irqsave(&priv->lock, flags);
1041 	if (set & TIOCM_RTS)
1042 		priv->line_control |= CONTROL_RTS;
1043 	if (set & TIOCM_DTR)
1044 		priv->line_control |= CONTROL_DTR;
1045 	if (clear & TIOCM_RTS)
1046 		priv->line_control &= ~CONTROL_RTS;
1047 	if (clear & TIOCM_DTR)
1048 		priv->line_control &= ~CONTROL_DTR;
1049 	control = priv->line_control;
1050 	spin_unlock_irqrestore(&priv->lock, flags);
1051 
1052 	ret = pl2303_set_control_lines(port, control);
1053 	if (ret)
1054 		return usb_translate_errors(ret);
1055 
1056 	return 0;
1057 }
1058 
1059 static int pl2303_tiocmget(struct tty_struct *tty)
1060 {
1061 	struct usb_serial_port *port = tty->driver_data;
1062 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1063 	unsigned long flags;
1064 	unsigned int mcr;
1065 	unsigned int status;
1066 	unsigned int result;
1067 
1068 	spin_lock_irqsave(&priv->lock, flags);
1069 	mcr = priv->line_control;
1070 	status = priv->line_status;
1071 	spin_unlock_irqrestore(&priv->lock, flags);
1072 
1073 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
1074 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
1075 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
1076 		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
1077 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
1078 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
1079 
1080 	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
1081 
1082 	return result;
1083 }
1084 
1085 static int pl2303_carrier_raised(struct usb_serial_port *port)
1086 {
1087 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1088 
1089 	if (priv->line_status & UART_DCD)
1090 		return 1;
1091 
1092 	return 0;
1093 }
1094 
1095 static int pl2303_set_break(struct usb_serial_port *port, bool enable)
1096 {
1097 	struct usb_serial *serial = port->serial;
1098 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
1099 	u16 state;
1100 	int result;
1101 
1102 	if (spriv->quirks & PL2303_QUIRK_NO_BREAK_GETLINE)
1103 		return -ENOTTY;
1104 
1105 	if (enable)
1106 		state = BREAK_ON;
1107 	else
1108 		state = BREAK_OFF;
1109 
1110 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1111 			state == BREAK_OFF ? "off" : "on");
1112 
1113 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1114 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
1115 				 0, NULL, 0, 100);
1116 	if (result) {
1117 		dev_err(&port->dev, "error sending break = %d\n", result);
1118 		return result;
1119 	}
1120 
1121 	return 0;
1122 }
1123 
1124 static int pl2303_break_ctl(struct tty_struct *tty, int state)
1125 {
1126 	struct usb_serial_port *port = tty->driver_data;
1127 
1128 	return pl2303_set_break(port, state);
1129 }
1130 
1131 static void pl2303_update_line_status(struct usb_serial_port *port,
1132 				      unsigned char *data,
1133 				      unsigned int actual_length)
1134 {
1135 	struct usb_serial *serial = port->serial;
1136 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
1137 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1138 	struct tty_struct *tty;
1139 	unsigned long flags;
1140 	unsigned int status_idx = UART_STATE_INDEX;
1141 	u8 status;
1142 	u8 delta;
1143 
1144 	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
1145 		status_idx = 0;
1146 
1147 	if (actual_length < status_idx + 1)
1148 		return;
1149 
1150 	status = data[status_idx];
1151 
1152 	/* Save off the uart status for others to look at */
1153 	spin_lock_irqsave(&priv->lock, flags);
1154 	delta = priv->line_status ^ status;
1155 	priv->line_status = status;
1156 	spin_unlock_irqrestore(&priv->lock, flags);
1157 
1158 	if (status & UART_BREAK_ERROR)
1159 		usb_serial_handle_break(port);
1160 
1161 	if (delta & UART_STATE_MSR_MASK) {
1162 		if (delta & UART_CTS)
1163 			port->icount.cts++;
1164 		if (delta & UART_DSR)
1165 			port->icount.dsr++;
1166 		if (delta & UART_RING)
1167 			port->icount.rng++;
1168 		if (delta & UART_DCD) {
1169 			port->icount.dcd++;
1170 			tty = tty_port_tty_get(&port->port);
1171 			if (tty) {
1172 				usb_serial_handle_dcd_change(port, tty,
1173 							status & UART_DCD);
1174 				tty_kref_put(tty);
1175 			}
1176 		}
1177 
1178 		wake_up_interruptible(&port->port.delta_msr_wait);
1179 	}
1180 }
1181 
1182 static void pl2303_read_int_callback(struct urb *urb)
1183 {
1184 	struct usb_serial_port *port =  urb->context;
1185 	unsigned char *data = urb->transfer_buffer;
1186 	unsigned int actual_length = urb->actual_length;
1187 	int status = urb->status;
1188 	int retval;
1189 
1190 	switch (status) {
1191 	case 0:
1192 		/* success */
1193 		break;
1194 	case -ECONNRESET:
1195 	case -ENOENT:
1196 	case -ESHUTDOWN:
1197 		/* this urb is terminated, clean up */
1198 		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1199 			__func__, status);
1200 		return;
1201 	default:
1202 		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1203 			__func__, status);
1204 		goto exit;
1205 	}
1206 
1207 	usb_serial_debug_data(&port->dev, __func__,
1208 			      urb->actual_length, urb->transfer_buffer);
1209 
1210 	pl2303_update_line_status(port, data, actual_length);
1211 
1212 exit:
1213 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1214 	if (retval) {
1215 		dev_err(&port->dev,
1216 			"%s - usb_submit_urb failed with result %d\n",
1217 			__func__, retval);
1218 	}
1219 }
1220 
1221 static void pl2303_process_read_urb(struct urb *urb)
1222 {
1223 	struct usb_serial_port *port = urb->context;
1224 	struct pl2303_private *priv = usb_get_serial_port_data(port);
1225 	unsigned char *data = urb->transfer_buffer;
1226 	char tty_flag = TTY_NORMAL;
1227 	unsigned long flags;
1228 	u8 line_status;
1229 	int i;
1230 
1231 	/* update line status */
1232 	spin_lock_irqsave(&priv->lock, flags);
1233 	line_status = priv->line_status;
1234 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1235 	spin_unlock_irqrestore(&priv->lock, flags);
1236 
1237 	if (!urb->actual_length)
1238 		return;
1239 
1240 	/*
1241 	 * Break takes precedence over parity, which takes precedence over
1242 	 * framing errors.
1243 	 */
1244 	if (line_status & UART_BREAK_ERROR)
1245 		tty_flag = TTY_BREAK;
1246 	else if (line_status & UART_PARITY_ERROR)
1247 		tty_flag = TTY_PARITY;
1248 	else if (line_status & UART_FRAME_ERROR)
1249 		tty_flag = TTY_FRAME;
1250 
1251 	if (tty_flag != TTY_NORMAL)
1252 		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1253 								tty_flag);
1254 	/* overrun is special, not associated with a char */
1255 	if (line_status & UART_OVERRUN_ERROR)
1256 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1257 
1258 	if (port->sysrq) {
1259 		for (i = 0; i < urb->actual_length; ++i)
1260 			if (!usb_serial_handle_sysrq_char(port, data[i]))
1261 				tty_insert_flip_char(&port->port, data[i],
1262 						tty_flag);
1263 	} else {
1264 		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1265 							urb->actual_length);
1266 	}
1267 
1268 	tty_flip_buffer_push(&port->port);
1269 }
1270 
1271 static struct usb_serial_driver pl2303_device = {
1272 	.driver = {
1273 		.name =		"pl2303",
1274 	},
1275 	.id_table =		id_table,
1276 	.num_bulk_in =		1,
1277 	.num_bulk_out =		1,
1278 	.num_interrupt_in =	0,	/* see pl2303_calc_num_ports */
1279 	.bulk_in_size =		256,
1280 	.bulk_out_size =	256,
1281 	.open =			pl2303_open,
1282 	.close =		pl2303_close,
1283 	.dtr_rts =		pl2303_dtr_rts,
1284 	.carrier_raised =	pl2303_carrier_raised,
1285 	.break_ctl =		pl2303_break_ctl,
1286 	.set_termios =		pl2303_set_termios,
1287 	.tiocmget =		pl2303_tiocmget,
1288 	.tiocmset =		pl2303_tiocmset,
1289 	.tiocmiwait =		usb_serial_generic_tiocmiwait,
1290 	.process_read_urb =	pl2303_process_read_urb,
1291 	.read_int_callback =	pl2303_read_int_callback,
1292 	.probe =		pl2303_probe,
1293 	.calc_num_ports =	pl2303_calc_num_ports,
1294 	.attach =		pl2303_startup,
1295 	.release =		pl2303_release,
1296 	.port_probe =		pl2303_port_probe,
1297 	.port_remove =		pl2303_port_remove,
1298 };
1299 
1300 static struct usb_serial_driver * const serial_drivers[] = {
1301 	&pl2303_device, NULL
1302 };
1303 
1304 module_usb_serial_driver(serial_drivers, id_table);
1305 
1306 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1307 MODULE_LICENSE("GPL v2");
1308