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
35static 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_LM930_PRODUCT_ID) },
110	{ USB_DEVICE(HP_VENDOR_ID, HP_LM940_PRODUCT_ID) },
111	{ USB_DEVICE(HP_VENDOR_ID, HP_TD620_PRODUCT_ID) },
112	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
113	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
114	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
115	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
116	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
117	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530GC_PRODUCT_ID) },
118	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
119	{ USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
120	{ USB_DEVICE(IBM_VENDOR_ID, IBM_PRODUCT_ID) },
121	{ }					/* Terminating entry */
122};
123
124MODULE_DEVICE_TABLE(usb, id_table);
125
126#define SET_LINE_REQUEST_TYPE		0x21
127#define SET_LINE_REQUEST		0x20
128
129#define SET_CONTROL_REQUEST_TYPE	0x21
130#define SET_CONTROL_REQUEST		0x22
131#define CONTROL_DTR			0x01
132#define CONTROL_RTS			0x02
133
134#define BREAK_REQUEST_TYPE		0x21
135#define BREAK_REQUEST			0x23
136#define BREAK_ON			0xffff
137#define BREAK_OFF			0x0000
138
139#define GET_LINE_REQUEST_TYPE		0xa1
140#define GET_LINE_REQUEST		0x21
141
142#define VENDOR_WRITE_REQUEST_TYPE	0x40
143#define VENDOR_WRITE_REQUEST		0x01
144#define VENDOR_WRITE_NREQUEST		0x80
145
146#define VENDOR_READ_REQUEST_TYPE	0xc0
147#define VENDOR_READ_REQUEST		0x01
148#define VENDOR_READ_NREQUEST		0x81
149
150#define UART_STATE_INDEX		8
151#define UART_STATE_MSR_MASK		0x8b
152#define UART_STATE_TRANSIENT_MASK	0x74
153#define UART_DCD			0x01
154#define UART_DSR			0x02
155#define UART_BREAK_ERROR		0x04
156#define UART_RING			0x08
157#define UART_FRAME_ERROR		0x10
158#define UART_PARITY_ERROR		0x20
159#define UART_OVERRUN_ERROR		0x40
160#define UART_CTS			0x80
161
162#define PL2303_FLOWCTRL_MASK		0xf0
163
164#define PL2303_READ_TYPE_HX_STATUS	0x8080
165
166#define PL2303_HXN_RESET_REG		0x07
167#define PL2303_HXN_RESET_UPSTREAM_PIPE	0x02
168#define PL2303_HXN_RESET_DOWNSTREAM_PIPE	0x01
169
170#define PL2303_HXN_FLOWCTRL_REG		0x0a
171#define PL2303_HXN_FLOWCTRL_MASK	0x1c
172#define PL2303_HXN_FLOWCTRL_NONE	0x1c
173#define PL2303_HXN_FLOWCTRL_RTS_CTS	0x18
174#define PL2303_HXN_FLOWCTRL_XON_XOFF	0x0c
175
176static void pl2303_set_break(struct usb_serial_port *port, bool enable);
177
178enum pl2303_type {
179	TYPE_01,	/* Type 0 and 1 (difference unknown) */
180	TYPE_HX,	/* HX version of the pl2303 chip */
181	TYPE_HXN,	/* HXN version of the pl2303 chip */
182	TYPE_COUNT
183};
184
185struct pl2303_type_data {
186	speed_t max_baud_rate;
187	unsigned long quirks;
188	unsigned int no_autoxonxoff:1;
189	unsigned int no_divisors:1;
190};
191
192struct pl2303_serial_private {
193	const struct pl2303_type_data *type;
194	unsigned long quirks;
195};
196
197struct pl2303_private {
198	spinlock_t lock;
199	u8 line_control;
200	u8 line_status;
201
202	u8 line_settings[7];
203};
204
205static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
206	[TYPE_01] = {
207		.max_baud_rate		= 1228800,
208		.quirks			= PL2303_QUIRK_LEGACY,
209		.no_autoxonxoff		= true,
210	},
211	[TYPE_HX] = {
212		.max_baud_rate		= 12000000,
213	},
214	[TYPE_HXN] = {
215		.max_baud_rate		= 12000000,
216		.no_divisors		= true,
217	},
218};
219
220static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
221							unsigned char buf[1])
222{
223	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
224	struct device *dev = &serial->interface->dev;
225	u8 request;
226	int res;
227
228	if (spriv->type == &pl2303_type_data[TYPE_HXN])
229		request = VENDOR_READ_NREQUEST;
230	else
231		request = VENDOR_READ_REQUEST;
232
233	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
234			request, VENDOR_READ_REQUEST_TYPE,
235			value, 0, buf, 1, 100);
236	if (res != 1) {
237		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
238								value, res);
239		if (res >= 0)
240			res = -EIO;
241
242		return res;
243	}
244
245	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
246
247	return 0;
248}
249
250static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
251{
252	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
253	struct device *dev = &serial->interface->dev;
254	u8 request;
255	int res;
256
257	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
258
259	if (spriv->type == &pl2303_type_data[TYPE_HXN])
260		request = VENDOR_WRITE_NREQUEST;
261	else
262		request = VENDOR_WRITE_REQUEST;
263
264	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
265			request, VENDOR_WRITE_REQUEST_TYPE,
266			value, index, NULL, 0, 100);
267	if (res) {
268		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
269								value, res);
270		return res;
271	}
272
273	return 0;
274}
275
276static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
277{
278	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
279	int ret = 0;
280	u8 *buf;
281
282	buf = kmalloc(1, GFP_KERNEL);
283	if (!buf)
284		return -ENOMEM;
285
286	if (spriv->type == &pl2303_type_data[TYPE_HXN])
287		ret = pl2303_vendor_read(serial, reg, buf);
288	else
289		ret = pl2303_vendor_read(serial, reg | 0x80, buf);
290
291	if (ret)
292		goto out_free;
293
294	*buf &= ~mask;
295	*buf |= val & mask;
296
297	ret = pl2303_vendor_write(serial, reg, *buf);
298out_free:
299	kfree(buf);
300
301	return ret;
302}
303
304static int pl2303_probe(struct usb_serial *serial,
305					const struct usb_device_id *id)
306{
307	usb_set_serial_data(serial, (void *)id->driver_info);
308
309	return 0;
310}
311
312/*
313 * Use interrupt endpoint from first interface if available.
314 *
315 * This is needed due to the looney way its endpoints are set up.
316 */
317static int pl2303_endpoint_hack(struct usb_serial *serial,
318					struct usb_serial_endpoints *epds)
319{
320	struct usb_interface *interface = serial->interface;
321	struct usb_device *dev = serial->dev;
322	struct device *ddev = &interface->dev;
323	struct usb_host_interface *iface_desc;
324	struct usb_endpoint_descriptor *endpoint;
325	unsigned int i;
326
327	if (interface == dev->actconfig->interface[0])
328		return 0;
329
330	/* check out the endpoints of the other interface */
331	iface_desc = dev->actconfig->interface[0]->cur_altsetting;
332
333	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
334		endpoint = &iface_desc->endpoint[i].desc;
335
336		if (!usb_endpoint_is_int_in(endpoint))
337			continue;
338
339		dev_dbg(ddev, "found interrupt in on separate interface\n");
340		if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
341			epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
342	}
343
344	return 0;
345}
346
347static int pl2303_calc_num_ports(struct usb_serial *serial,
348					struct usb_serial_endpoints *epds)
349{
350	unsigned long quirks = (unsigned long)usb_get_serial_data(serial);
351	struct device *dev = &serial->interface->dev;
352	int ret;
353
354	if (quirks & PL2303_QUIRK_ENDPOINT_HACK) {
355		ret = pl2303_endpoint_hack(serial, epds);
356		if (ret)
357			return ret;
358	}
359
360	if (epds->num_interrupt_in < 1) {
361		dev_err(dev, "required interrupt-in endpoint missing\n");
362		return -ENODEV;
363	}
364
365	return 1;
366}
367
368static int pl2303_startup(struct usb_serial *serial)
369{
370	struct pl2303_serial_private *spriv;
371	enum pl2303_type type = TYPE_01;
372	unsigned char *buf;
373	int res;
374
375	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
376	if (!spriv)
377		return -ENOMEM;
378
379	buf = kmalloc(1, GFP_KERNEL);
380	if (!buf) {
381		kfree(spriv);
382		return -ENOMEM;
383	}
384
385	if (serial->dev->descriptor.bDeviceClass == 0x02)
386		type = TYPE_01;		/* type 0 */
387	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
388		type = TYPE_HX;
389	else if (serial->dev->descriptor.bDeviceClass == 0x00)
390		type = TYPE_01;		/* type 1 */
391	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
392		type = TYPE_01;		/* type 1 */
393	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
394
395	if (type == TYPE_HX) {
396		res = usb_control_msg(serial->dev,
397				usb_rcvctrlpipe(serial->dev, 0),
398				VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
399				PL2303_READ_TYPE_HX_STATUS, 0, buf, 1, 100);
400		if (res != 1)
401			type = TYPE_HXN;
402	}
403
404	spriv->type = &pl2303_type_data[type];
405	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
406	spriv->quirks |= spriv->type->quirks;
407
408	usb_set_serial_data(serial, spriv);
409
410	if (type != TYPE_HXN) {
411		pl2303_vendor_read(serial, 0x8484, buf);
412		pl2303_vendor_write(serial, 0x0404, 0);
413		pl2303_vendor_read(serial, 0x8484, buf);
414		pl2303_vendor_read(serial, 0x8383, buf);
415		pl2303_vendor_read(serial, 0x8484, buf);
416		pl2303_vendor_write(serial, 0x0404, 1);
417		pl2303_vendor_read(serial, 0x8484, buf);
418		pl2303_vendor_read(serial, 0x8383, buf);
419		pl2303_vendor_write(serial, 0, 1);
420		pl2303_vendor_write(serial, 1, 0);
421		if (spriv->quirks & PL2303_QUIRK_LEGACY)
422			pl2303_vendor_write(serial, 2, 0x24);
423		else
424			pl2303_vendor_write(serial, 2, 0x44);
425	}
426
427	kfree(buf);
428
429	return 0;
430}
431
432static void pl2303_release(struct usb_serial *serial)
433{
434	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
435
436	kfree(spriv);
437}
438
439static int pl2303_port_probe(struct usb_serial_port *port)
440{
441	struct pl2303_private *priv;
442
443	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
444	if (!priv)
445		return -ENOMEM;
446
447	spin_lock_init(&priv->lock);
448
449	usb_set_serial_port_data(port, priv);
450
451	port->port.drain_delay = 256;
452
453	return 0;
454}
455
456static int pl2303_port_remove(struct usb_serial_port *port)
457{
458	struct pl2303_private *priv = usb_get_serial_port_data(port);
459
460	kfree(priv);
461
462	return 0;
463}
464
465static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
466{
467	struct usb_device *dev = port->serial->dev;
468	int retval;
469
470	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
471
472	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
473				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
474				 value, 0, NULL, 0, 100);
475	if (retval)
476		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
477
478	return retval;
479}
480
481/*
482 * Returns the nearest supported baud rate that can be set directly without
483 * using divisors.
484 */
485static speed_t pl2303_get_supported_baud_rate(speed_t baud)
486{
487	static const speed_t baud_sup[] = {
488		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
489		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
490		614400, 921600, 1228800, 2457600, 3000000, 6000000
491	};
492
493	unsigned i;
494
495	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
496		if (baud_sup[i] > baud)
497			break;
498	}
499
500	if (i == ARRAY_SIZE(baud_sup))
501		baud = baud_sup[i - 1];
502	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
503		baud = baud_sup[i - 1];
504	else
505		baud = baud_sup[i];
506
507	return baud;
508}
509
510/*
511 * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
512 *       use 9600 baud.
513 */
514static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
515								speed_t baud)
516{
517	put_unaligned_le32(baud, buf);
518
519	return baud;
520}
521
522static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
523								speed_t baud)
524{
525	unsigned int baseline, mantissa, exponent;
526
527	/*
528	 * Apparently the formula is:
529	 *   baudrate = 12M * 32 / (mantissa * 4^exponent)
530	 * where
531	 *   mantissa = buf[8:0]
532	 *   exponent = buf[11:9]
533	 */
534	baseline = 12000000 * 32;
535	mantissa = baseline / baud;
536	if (mantissa == 0)
537		mantissa = 1;	/* Avoid dividing by zero if baud > 32*12M. */
538	exponent = 0;
539	while (mantissa >= 512) {
540		if (exponent < 7) {
541			mantissa >>= 2;	/* divide by 4 */
542			exponent++;
543		} else {
544			/* Exponent is maxed. Trim mantissa and leave. */
545			mantissa = 511;
546			break;
547		}
548	}
549
550	buf[3] = 0x80;
551	buf[2] = 0;
552	buf[1] = exponent << 1 | mantissa >> 8;
553	buf[0] = mantissa & 0xff;
554
555	/* Calculate and return the exact baud rate. */
556	baud = (baseline / mantissa) >> (exponent << 1);
557
558	return baud;
559}
560
561static void pl2303_encode_baud_rate(struct tty_struct *tty,
562					struct usb_serial_port *port,
563					u8 buf[4])
564{
565	struct usb_serial *serial = port->serial;
566	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
567	speed_t	baud_sup;
568	speed_t baud;
569
570	baud = tty_get_baud_rate(tty);
571	dev_dbg(&port->dev, "baud requested = %u\n", baud);
572	if (!baud)
573		return;
574
575	if (spriv->type->max_baud_rate)
576		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
577	/*
578	 * Use direct method for supported baud rates, otherwise use divisors.
579	 * Newer chip types do not support divisor encoding.
580	 */
581	if (spriv->type->no_divisors)
582		baud_sup = baud;
583	else
584		baud_sup = pl2303_get_supported_baud_rate(baud);
585
586	if (baud == baud_sup)
587		baud = pl2303_encode_baud_rate_direct(buf, baud);
588	else
589		baud = pl2303_encode_baud_rate_divisor(buf, baud);
590
591	/* Save resulting baud rate */
592	tty_encode_baud_rate(tty, baud, baud);
593	dev_dbg(&port->dev, "baud set = %u\n", baud);
594}
595
596static int pl2303_get_line_request(struct usb_serial_port *port,
597							unsigned char buf[7])
598{
599	struct usb_device *udev = port->serial->dev;
600	int ret;
601
602	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
603				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
604				0, 0, buf, 7, 100);
605	if (ret != 7) {
606		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
607
608		if (ret >= 0)
609			ret = -EIO;
610
611		return ret;
612	}
613
614	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
615
616	return 0;
617}
618
619static int pl2303_set_line_request(struct usb_serial_port *port,
620							unsigned char buf[7])
621{
622	struct usb_device *udev = port->serial->dev;
623	int ret;
624
625	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
626				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
627				0, 0, buf, 7, 100);
628	if (ret < 0) {
629		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
630		return ret;
631	}
632
633	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
634
635	return 0;
636}
637
638static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
639{
640	bool ixon_change;
641
642	ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
643			a->c_cc[VSTART] != b->c_cc[VSTART] ||
644			a->c_cc[VSTOP] != b->c_cc[VSTOP];
645
646	return tty_termios_hw_change(a, b) || ixon_change;
647}
648
649static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
650{
651	if (!I_IXON(tty) || I_IXANY(tty))
652		return false;
653
654	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
655		return false;
656
657	if (type->no_autoxonxoff)
658		return false;
659
660	return true;
661}
662
663static void pl2303_set_termios(struct tty_struct *tty,
664		struct usb_serial_port *port, struct ktermios *old_termios)
665{
666	struct usb_serial *serial = port->serial;
667	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
668	struct pl2303_private *priv = usb_get_serial_port_data(port);
669	unsigned long flags;
670	unsigned char *buf;
671	int ret;
672	u8 control;
673
674	if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
675		return;
676
677	buf = kzalloc(7, GFP_KERNEL);
678	if (!buf) {
679		/* Report back no change occurred */
680		if (old_termios)
681			tty->termios = *old_termios;
682		return;
683	}
684
685	pl2303_get_line_request(port, buf);
686
687	switch (C_CSIZE(tty)) {
688	case CS5:
689		buf[6] = 5;
690		break;
691	case CS6:
692		buf[6] = 6;
693		break;
694	case CS7:
695		buf[6] = 7;
696		break;
697	default:
698	case CS8:
699		buf[6] = 8;
700	}
701	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
702
703	/* For reference buf[0]:buf[3] baud rate value */
704	pl2303_encode_baud_rate(tty, port, &buf[0]);
705
706	/* For reference buf[4]=0 is 1 stop bits */
707	/* For reference buf[4]=1 is 1.5 stop bits */
708	/* For reference buf[4]=2 is 2 stop bits */
709	if (C_CSTOPB(tty)) {
710		/*
711		 * NOTE: Comply with "real" UARTs / RS232:
712		 *       use 1.5 instead of 2 stop bits with 5 data bits
713		 */
714		if (C_CSIZE(tty) == CS5) {
715			buf[4] = 1;
716			dev_dbg(&port->dev, "stop bits = 1.5\n");
717		} else {
718			buf[4] = 2;
719			dev_dbg(&port->dev, "stop bits = 2\n");
720		}
721	} else {
722		buf[4] = 0;
723		dev_dbg(&port->dev, "stop bits = 1\n");
724	}
725
726	if (C_PARENB(tty)) {
727		/* For reference buf[5]=0 is none parity */
728		/* For reference buf[5]=1 is odd parity */
729		/* For reference buf[5]=2 is even parity */
730		/* For reference buf[5]=3 is mark parity */
731		/* For reference buf[5]=4 is space parity */
732		if (C_PARODD(tty)) {
733			if (C_CMSPAR(tty)) {
734				buf[5] = 3;
735				dev_dbg(&port->dev, "parity = mark\n");
736			} else {
737				buf[5] = 1;
738				dev_dbg(&port->dev, "parity = odd\n");
739			}
740		} else {
741			if (C_CMSPAR(tty)) {
742				buf[5] = 4;
743				dev_dbg(&port->dev, "parity = space\n");
744			} else {
745				buf[5] = 2;
746				dev_dbg(&port->dev, "parity = even\n");
747			}
748		}
749	} else {
750		buf[5] = 0;
751		dev_dbg(&port->dev, "parity = none\n");
752	}
753
754	/*
755	 * Some PL2303 are known to lose bytes if you change serial settings
756	 * even to the same values as before. Thus we actually need to filter
757	 * in this specific case.
758	 *
759	 * Note that the tty_termios_hw_change check above is not sufficient
760	 * as a previously requested baud rate may differ from the one
761	 * actually used (and stored in old_termios).
762	 *
763	 * NOTE: No additional locking needed for line_settings as it is
764	 *       only used in set_termios, which is serialised against itself.
765	 */
766	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
767		ret = pl2303_set_line_request(port, buf);
768		if (!ret)
769			memcpy(priv->line_settings, buf, 7);
770	}
771
772	/* change control lines if we are switching to or from B0 */
773	spin_lock_irqsave(&priv->lock, flags);
774	control = priv->line_control;
775	if (C_BAUD(tty) == B0)
776		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
777	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
778		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
779	if (control != priv->line_control) {
780		control = priv->line_control;
781		spin_unlock_irqrestore(&priv->lock, flags);
782		pl2303_set_control_lines(port, control);
783	} else {
784		spin_unlock_irqrestore(&priv->lock, flags);
785	}
786
787	if (C_CRTSCTS(tty)) {
788		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
789			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
790		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
791			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
792					PL2303_HXN_FLOWCTRL_MASK,
793					PL2303_HXN_FLOWCTRL_RTS_CTS);
794		} else {
795			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
796		}
797	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
798		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
799			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
800					PL2303_HXN_FLOWCTRL_MASK,
801					PL2303_HXN_FLOWCTRL_XON_XOFF);
802		} else {
803			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
804		}
805	} else {
806		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
807			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
808					PL2303_HXN_FLOWCTRL_MASK,
809					PL2303_HXN_FLOWCTRL_NONE);
810		} else {
811			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
812		}
813	}
814
815	kfree(buf);
816}
817
818static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
819{
820	struct pl2303_private *priv = usb_get_serial_port_data(port);
821	unsigned long flags;
822	u8 control;
823
824	spin_lock_irqsave(&priv->lock, flags);
825	if (on)
826		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
827	else
828		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
829	control = priv->line_control;
830	spin_unlock_irqrestore(&priv->lock, flags);
831
832	pl2303_set_control_lines(port, control);
833}
834
835static void pl2303_close(struct usb_serial_port *port)
836{
837	usb_serial_generic_close(port);
838	usb_kill_urb(port->interrupt_in_urb);
839	pl2303_set_break(port, false);
840}
841
842static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
843{
844	struct usb_serial *serial = port->serial;
845	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
846	int result;
847
848	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
849		usb_clear_halt(serial->dev, port->write_urb->pipe);
850		usb_clear_halt(serial->dev, port->read_urb->pipe);
851	} else {
852		/* reset upstream data pipes */
853		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
854			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
855					PL2303_HXN_RESET_UPSTREAM_PIPE |
856					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
857		} else {
858			pl2303_vendor_write(serial, 8, 0);
859			pl2303_vendor_write(serial, 9, 0);
860		}
861	}
862
863	/* Setup termios */
864	if (tty)
865		pl2303_set_termios(tty, port, NULL);
866
867	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
868	if (result) {
869		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
870			result);
871		return result;
872	}
873
874	result = usb_serial_generic_open(tty, port);
875	if (result) {
876		usb_kill_urb(port->interrupt_in_urb);
877		return result;
878	}
879
880	return 0;
881}
882
883static int pl2303_tiocmset(struct tty_struct *tty,
884			   unsigned int set, unsigned int clear)
885{
886	struct usb_serial_port *port = tty->driver_data;
887	struct pl2303_private *priv = usb_get_serial_port_data(port);
888	unsigned long flags;
889	u8 control;
890	int ret;
891
892	spin_lock_irqsave(&priv->lock, flags);
893	if (set & TIOCM_RTS)
894		priv->line_control |= CONTROL_RTS;
895	if (set & TIOCM_DTR)
896		priv->line_control |= CONTROL_DTR;
897	if (clear & TIOCM_RTS)
898		priv->line_control &= ~CONTROL_RTS;
899	if (clear & TIOCM_DTR)
900		priv->line_control &= ~CONTROL_DTR;
901	control = priv->line_control;
902	spin_unlock_irqrestore(&priv->lock, flags);
903
904	ret = pl2303_set_control_lines(port, control);
905	if (ret)
906		return usb_translate_errors(ret);
907
908	return 0;
909}
910
911static int pl2303_tiocmget(struct tty_struct *tty)
912{
913	struct usb_serial_port *port = tty->driver_data;
914	struct pl2303_private *priv = usb_get_serial_port_data(port);
915	unsigned long flags;
916	unsigned int mcr;
917	unsigned int status;
918	unsigned int result;
919
920	spin_lock_irqsave(&priv->lock, flags);
921	mcr = priv->line_control;
922	status = priv->line_status;
923	spin_unlock_irqrestore(&priv->lock, flags);
924
925	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
926		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
927		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
928		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
929		  | ((status & UART_RING)	? TIOCM_RI  : 0)
930		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
931
932	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
933
934	return result;
935}
936
937static int pl2303_carrier_raised(struct usb_serial_port *port)
938{
939	struct pl2303_private *priv = usb_get_serial_port_data(port);
940
941	if (priv->line_status & UART_DCD)
942		return 1;
943
944	return 0;
945}
946
947static int pl2303_get_serial(struct tty_struct *tty,
948			struct serial_struct *ss)
949{
950	struct usb_serial_port *port = tty->driver_data;
951
952	ss->type = PORT_16654;
953	ss->line = port->minor;
954	ss->port = port->port_number;
955	ss->baud_base = 460800;
956	return 0;
957}
958
959static void pl2303_set_break(struct usb_serial_port *port, bool enable)
960{
961	struct usb_serial *serial = port->serial;
962	u16 state;
963	int result;
964
965	if (enable)
966		state = BREAK_ON;
967	else
968		state = BREAK_OFF;
969
970	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
971			state == BREAK_OFF ? "off" : "on");
972
973	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
974				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
975				 0, NULL, 0, 100);
976	if (result)
977		dev_err(&port->dev, "error sending break = %d\n", result);
978}
979
980static void pl2303_break_ctl(struct tty_struct *tty, int state)
981{
982	struct usb_serial_port *port = tty->driver_data;
983
984	pl2303_set_break(port, state);
985}
986
987static void pl2303_update_line_status(struct usb_serial_port *port,
988				      unsigned char *data,
989				      unsigned int actual_length)
990{
991	struct usb_serial *serial = port->serial;
992	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
993	struct pl2303_private *priv = usb_get_serial_port_data(port);
994	struct tty_struct *tty;
995	unsigned long flags;
996	unsigned int status_idx = UART_STATE_INDEX;
997	u8 status;
998	u8 delta;
999
1000	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
1001		status_idx = 0;
1002
1003	if (actual_length < status_idx + 1)
1004		return;
1005
1006	status = data[status_idx];
1007
1008	/* Save off the uart status for others to look at */
1009	spin_lock_irqsave(&priv->lock, flags);
1010	delta = priv->line_status ^ status;
1011	priv->line_status = status;
1012	spin_unlock_irqrestore(&priv->lock, flags);
1013
1014	if (status & UART_BREAK_ERROR)
1015		usb_serial_handle_break(port);
1016
1017	if (delta & UART_STATE_MSR_MASK) {
1018		if (delta & UART_CTS)
1019			port->icount.cts++;
1020		if (delta & UART_DSR)
1021			port->icount.dsr++;
1022		if (delta & UART_RING)
1023			port->icount.rng++;
1024		if (delta & UART_DCD) {
1025			port->icount.dcd++;
1026			tty = tty_port_tty_get(&port->port);
1027			if (tty) {
1028				usb_serial_handle_dcd_change(port, tty,
1029							status & UART_DCD);
1030				tty_kref_put(tty);
1031			}
1032		}
1033
1034		wake_up_interruptible(&port->port.delta_msr_wait);
1035	}
1036}
1037
1038static void pl2303_read_int_callback(struct urb *urb)
1039{
1040	struct usb_serial_port *port =  urb->context;
1041	unsigned char *data = urb->transfer_buffer;
1042	unsigned int actual_length = urb->actual_length;
1043	int status = urb->status;
1044	int retval;
1045
1046	switch (status) {
1047	case 0:
1048		/* success */
1049		break;
1050	case -ECONNRESET:
1051	case -ENOENT:
1052	case -ESHUTDOWN:
1053		/* this urb is terminated, clean up */
1054		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1055			__func__, status);
1056		return;
1057	default:
1058		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1059			__func__, status);
1060		goto exit;
1061	}
1062
1063	usb_serial_debug_data(&port->dev, __func__,
1064			      urb->actual_length, urb->transfer_buffer);
1065
1066	pl2303_update_line_status(port, data, actual_length);
1067
1068exit:
1069	retval = usb_submit_urb(urb, GFP_ATOMIC);
1070	if (retval) {
1071		dev_err(&port->dev,
1072			"%s - usb_submit_urb failed with result %d\n",
1073			__func__, retval);
1074	}
1075}
1076
1077static void pl2303_process_read_urb(struct urb *urb)
1078{
1079	struct usb_serial_port *port = urb->context;
1080	struct pl2303_private *priv = usb_get_serial_port_data(port);
1081	unsigned char *data = urb->transfer_buffer;
1082	char tty_flag = TTY_NORMAL;
1083	unsigned long flags;
1084	u8 line_status;
1085	int i;
1086
1087	/* update line status */
1088	spin_lock_irqsave(&priv->lock, flags);
1089	line_status = priv->line_status;
1090	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1091	spin_unlock_irqrestore(&priv->lock, flags);
1092
1093	if (!urb->actual_length)
1094		return;
1095
1096	/*
1097	 * Break takes precedence over parity, which takes precedence over
1098	 * framing errors.
1099	 */
1100	if (line_status & UART_BREAK_ERROR)
1101		tty_flag = TTY_BREAK;
1102	else if (line_status & UART_PARITY_ERROR)
1103		tty_flag = TTY_PARITY;
1104	else if (line_status & UART_FRAME_ERROR)
1105		tty_flag = TTY_FRAME;
1106
1107	if (tty_flag != TTY_NORMAL)
1108		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1109								tty_flag);
1110	/* overrun is special, not associated with a char */
1111	if (line_status & UART_OVERRUN_ERROR)
1112		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1113
1114	if (port->sysrq) {
1115		for (i = 0; i < urb->actual_length; ++i)
1116			if (!usb_serial_handle_sysrq_char(port, data[i]))
1117				tty_insert_flip_char(&port->port, data[i],
1118						tty_flag);
1119	} else {
1120		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1121							urb->actual_length);
1122	}
1123
1124	tty_flip_buffer_push(&port->port);
1125}
1126
1127static struct usb_serial_driver pl2303_device = {
1128	.driver = {
1129		.owner =	THIS_MODULE,
1130		.name =		"pl2303",
1131	},
1132	.id_table =		id_table,
1133	.num_bulk_in =		1,
1134	.num_bulk_out =		1,
1135	.num_interrupt_in =	0,	/* see pl2303_calc_num_ports */
1136	.bulk_in_size =		256,
1137	.bulk_out_size =	256,
1138	.open =			pl2303_open,
1139	.close =		pl2303_close,
1140	.dtr_rts =		pl2303_dtr_rts,
1141	.carrier_raised =	pl2303_carrier_raised,
1142	.get_serial =		pl2303_get_serial,
1143	.break_ctl =		pl2303_break_ctl,
1144	.set_termios =		pl2303_set_termios,
1145	.tiocmget =		pl2303_tiocmget,
1146	.tiocmset =		pl2303_tiocmset,
1147	.tiocmiwait =		usb_serial_generic_tiocmiwait,
1148	.process_read_urb =	pl2303_process_read_urb,
1149	.read_int_callback =	pl2303_read_int_callback,
1150	.probe =		pl2303_probe,
1151	.calc_num_ports =	pl2303_calc_num_ports,
1152	.attach =		pl2303_startup,
1153	.release =		pl2303_release,
1154	.port_probe =		pl2303_port_probe,
1155	.port_remove =		pl2303_port_remove,
1156};
1157
1158static struct usb_serial_driver * const serial_drivers[] = {
1159	&pl2303_device, NULL
1160};
1161
1162module_usb_serial_driver(serial_drivers, id_table);
1163
1164MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1165MODULE_LICENSE("GPL v2");
1166