xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision d23bac9f8b3cf1ad674d6390364d559103013213)
1 /*
2  * Silicon Laboratories CP2101/CP2102 USB to RS232 serial adaptor driver
3  *
4  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License version
8  *	2 as published by the Free Software Foundation.
9  *
10  * Support to set flow control line levels using TIOCMGET and TIOCMSET
11  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
12  * control thanks to Munir Nassar nassarmu@real-time.com
13  *
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <linux/tty.h>
20 #include <linux/tty_flip.h>
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/usb.h>
24 #include <linux/uaccess.h>
25 #include <linux/usb/serial.h>
26 
27 /*
28  * Version Information
29  */
30 #define DRIVER_VERSION "v0.08"
31 #define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver"
32 
33 /*
34  * Function Prototypes
35  */
36 static int cp2101_open(struct tty_struct *, struct usb_serial_port *,
37 							struct file *);
38 static void cp2101_cleanup(struct usb_serial_port *);
39 static void cp2101_close(struct tty_struct *, struct usb_serial_port *,
40 							struct file*);
41 static void cp2101_get_termios(struct tty_struct *);
42 static void cp2101_set_termios(struct tty_struct *, struct usb_serial_port *,
43 							struct ktermios*);
44 static int cp2101_tiocmget(struct tty_struct *, struct file *);
45 static int cp2101_tiocmset(struct tty_struct *, struct file *,
46 		unsigned int, unsigned int);
47 static void cp2101_break_ctl(struct tty_struct *, int);
48 static int cp2101_startup(struct usb_serial *);
49 static void cp2101_shutdown(struct usb_serial *);
50 
51 
52 static int debug;
53 
54 static struct usb_device_id id_table [] = {
55 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
56 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
57 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
58 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
59 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
60 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
61 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
62 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
63 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
64 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
65 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
66 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
67 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
68 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
69 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
70 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
71 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
72 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
73 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
74 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
75 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
76 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
77 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
78 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
79 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
80 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
81 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
82 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
83 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
84 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
85 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
86 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
87 	{ USB_DEVICE(0x10c4, 0x8293) }, /* Telegesys ETRX2USB */
88 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
89 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
90 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
91 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
92 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
93 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
94 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
95 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
96 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
97 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
98 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
99 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
100 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
101 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
102 	{ } /* Terminating Entry */
103 };
104 
105 MODULE_DEVICE_TABLE(usb, id_table);
106 
107 static struct usb_driver cp2101_driver = {
108 	.name		= "cp2101",
109 	.probe		= usb_serial_probe,
110 	.disconnect	= usb_serial_disconnect,
111 	.id_table	= id_table,
112 	.no_dynamic_id	= 	1,
113 };
114 
115 static struct usb_serial_driver cp2101_device = {
116 	.driver = {
117 		.owner =	THIS_MODULE,
118 		.name = 	"cp2101",
119 	},
120 	.usb_driver		= &cp2101_driver,
121 	.id_table		= id_table,
122 	.num_ports		= 1,
123 	.open			= cp2101_open,
124 	.close			= cp2101_close,
125 	.break_ctl		= cp2101_break_ctl,
126 	.set_termios		= cp2101_set_termios,
127 	.tiocmget 		= cp2101_tiocmget,
128 	.tiocmset		= cp2101_tiocmset,
129 	.attach			= cp2101_startup,
130 	.shutdown		= cp2101_shutdown,
131 };
132 
133 /* Config request types */
134 #define REQTYPE_HOST_TO_DEVICE	0x41
135 #define REQTYPE_DEVICE_TO_HOST	0xc1
136 
137 /* Config SET requests. To GET, add 1 to the request number */
138 #define CP2101_UART 		0x00	/* Enable / Disable */
139 #define CP2101_BAUDRATE		0x01	/* (BAUD_RATE_GEN_FREQ / baudrate) */
140 #define CP2101_BITS		0x03	/* 0x(0)(databits)(parity)(stopbits) */
141 #define CP2101_BREAK		0x05	/* On / Off */
142 #define CP2101_CONTROL		0x07	/* Flow control line states */
143 #define CP2101_MODEMCTL		0x13	/* Modem controls */
144 #define CP2101_CONFIG_6		0x19	/* 6 bytes of config data ??? */
145 
146 /* CP2101_UART */
147 #define UART_ENABLE		0x0001
148 #define UART_DISABLE		0x0000
149 
150 /* CP2101_BAUDRATE */
151 #define BAUD_RATE_GEN_FREQ	0x384000
152 
153 /* CP2101_BITS */
154 #define BITS_DATA_MASK		0X0f00
155 #define BITS_DATA_5		0X0500
156 #define BITS_DATA_6		0X0600
157 #define BITS_DATA_7		0X0700
158 #define BITS_DATA_8		0X0800
159 #define BITS_DATA_9		0X0900
160 
161 #define BITS_PARITY_MASK	0x00f0
162 #define BITS_PARITY_NONE	0x0000
163 #define BITS_PARITY_ODD		0x0010
164 #define BITS_PARITY_EVEN	0x0020
165 #define BITS_PARITY_MARK	0x0030
166 #define BITS_PARITY_SPACE	0x0040
167 
168 #define BITS_STOP_MASK		0x000f
169 #define BITS_STOP_1		0x0000
170 #define BITS_STOP_1_5		0x0001
171 #define BITS_STOP_2		0x0002
172 
173 /* CP2101_BREAK */
174 #define BREAK_ON		0x0000
175 #define BREAK_OFF		0x0001
176 
177 /* CP2101_CONTROL */
178 #define CONTROL_DTR		0x0001
179 #define CONTROL_RTS		0x0002
180 #define CONTROL_CTS		0x0010
181 #define CONTROL_DSR		0x0020
182 #define CONTROL_RING		0x0040
183 #define CONTROL_DCD		0x0080
184 #define CONTROL_WRITE_DTR	0x0100
185 #define CONTROL_WRITE_RTS	0x0200
186 
187 /*
188  * cp2101_get_config
189  * Reads from the CP2101 configuration registers
190  * 'size' is specified in bytes.
191  * 'data' is a pointer to a pre-allocated array of integers large
192  * enough to hold 'size' bytes (with 4 bytes to each integer)
193  */
194 static int cp2101_get_config(struct usb_serial_port *port, u8 request,
195 		unsigned int *data, int size)
196 {
197 	struct usb_serial *serial = port->serial;
198 	__le32 *buf;
199 	int result, i, length;
200 
201 	/* Number of integers required to contain the array */
202 	length = (((size - 1) | 3) + 1)/4;
203 
204 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
205 	if (!buf) {
206 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
207 		return -ENOMEM;
208 	}
209 
210 	/* For get requests, the request number must be incremented */
211 	request++;
212 
213 	/* Issue the request, attempting to read 'size' bytes */
214 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
215 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
216 				0, buf, size, 300);
217 
218 	/* Convert data into an array of integers */
219 	for (i = 0; i < length; i++)
220 		data[i] = le32_to_cpu(buf[i]);
221 
222 	kfree(buf);
223 
224 	if (result != size) {
225 		dbg("%s - Unable to send config request, "
226 				"request=0x%x size=%d result=%d\n",
227 				__func__, request, size, result);
228 		return -EPROTO;
229 	}
230 
231 	return 0;
232 }
233 
234 /*
235  * cp2101_set_config
236  * Writes to the CP2101 configuration registers
237  * Values less than 16 bits wide are sent directly
238  * 'size' is specified in bytes.
239  */
240 static int cp2101_set_config(struct usb_serial_port *port, u8 request,
241 		unsigned int *data, int size)
242 {
243 	struct usb_serial *serial = port->serial;
244 	__le32 *buf;
245 	int result, i, length;
246 
247 	/* Number of integers required to contain the array */
248 	length = (((size - 1) | 3) + 1)/4;
249 
250 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
251 	if (!buf) {
252 		dev_err(&port->dev, "%s - out of memory.\n",
253 				__func__);
254 		return -ENOMEM;
255 	}
256 
257 	/* Array of integers into bytes */
258 	for (i = 0; i < length; i++)
259 		buf[i] = cpu_to_le32(data[i]);
260 
261 	if (size > 2) {
262 		result = usb_control_msg(serial->dev,
263 				usb_sndctrlpipe(serial->dev, 0),
264 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
265 				0, buf, size, 300);
266 	} else {
267 		result = usb_control_msg(serial->dev,
268 				usb_sndctrlpipe(serial->dev, 0),
269 				request, REQTYPE_HOST_TO_DEVICE, data[0],
270 				0, NULL, 0, 300);
271 	}
272 
273 	kfree(buf);
274 
275 	if ((size > 2 && result != size) || result < 0) {
276 		dbg("%s - Unable to send request, "
277 				"request=0x%x size=%d result=%d\n",
278 				__func__, request, size, result);
279 		return -EPROTO;
280 	}
281 
282 	/* Single data value */
283 	result = usb_control_msg(serial->dev,
284 			usb_sndctrlpipe(serial->dev, 0),
285 			request, REQTYPE_HOST_TO_DEVICE, data[0],
286 			0, NULL, 0, 300);
287 	return 0;
288 }
289 
290 /*
291  * cp2101_set_config_single
292  * Convenience function for calling cp2101_set_config on single data values
293  * without requiring an integer pointer
294  */
295 static inline int cp2101_set_config_single(struct usb_serial_port *port,
296 		u8 request, unsigned int data)
297 {
298 	return cp2101_set_config(port, request, &data, 2);
299 }
300 
301 /*
302  * cp2101_quantise_baudrate
303  * Quantises the baud rate as per AN205 Table 1
304  */
305 static unsigned int cp2101_quantise_baudrate(unsigned int baud) {
306 	if      (baud <= 56)       baud = 0;
307 	else if (baud <= 300)      baud = 300;
308 	else if (baud <= 600)      baud = 600;
309 	else if (baud <= 1200)     baud = 1200;
310 	else if (baud <= 1800)     baud = 1800;
311 	else if (baud <= 2400)     baud = 2400;
312 	else if (baud <= 4000)     baud = 4000;
313 	else if (baud <= 4803)     baud = 4800;
314 	else if (baud <= 7207)     baud = 7200;
315 	else if (baud <= 9612)     baud = 9600;
316 	else if (baud <= 14428)    baud = 14400;
317 	else if (baud <= 16062)    baud = 16000;
318 	else if (baud <= 19250)    baud = 19200;
319 	else if (baud <= 28912)    baud = 28800;
320 	else if (baud <= 38601)    baud = 38400;
321 	else if (baud <= 51558)    baud = 51200;
322 	else if (baud <= 56280)    baud = 56000;
323 	else if (baud <= 58053)    baud = 57600;
324 	else if (baud <= 64111)    baud = 64000;
325 	else if (baud <= 77608)    baud = 76800;
326 	else if (baud <= 117028)   baud = 115200;
327 	else if (baud <= 129347)   baud = 128000;
328 	else if (baud <= 156868)   baud = 153600;
329 	else if (baud <= 237832)   baud = 230400;
330 	else if (baud <= 254234)   baud = 250000;
331 	else if (baud <= 273066)   baud = 256000;
332 	else if (baud <= 491520)   baud = 460800;
333 	else if (baud <= 567138)   baud = 500000;
334 	else if (baud <= 670254)   baud = 576000;
335 	else if (baud <= 1053257)  baud = 921600;
336 	else if (baud <= 1474560)  baud = 1228800;
337 	else if (baud <= 2457600)  baud = 1843200;
338 	else                       baud = 3686400;
339 	return baud;
340 }
341 
342 static int cp2101_open(struct tty_struct *tty, struct usb_serial_port *port,
343 				struct file *filp)
344 {
345 	struct usb_serial *serial = port->serial;
346 	int result;
347 
348 	dbg("%s - port %d", __func__, port->number);
349 
350 	if (cp2101_set_config_single(port, CP2101_UART, UART_ENABLE)) {
351 		dev_err(&port->dev, "%s - Unable to enable UART\n",
352 				__func__);
353 		return -EPROTO;
354 	}
355 
356 	/* Start reading from the device */
357 	usb_fill_bulk_urb(port->read_urb, serial->dev,
358 			usb_rcvbulkpipe(serial->dev,
359 			port->bulk_in_endpointAddress),
360 			port->read_urb->transfer_buffer,
361 			port->read_urb->transfer_buffer_length,
362 			serial->type->read_bulk_callback,
363 			port);
364 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
365 	if (result) {
366 		dev_err(&port->dev, "%s - failed resubmitting read urb, "
367 				"error %d\n", __func__, result);
368 		return result;
369 	}
370 
371 	/* Configure the termios structure */
372 	cp2101_get_termios(tty);
373 
374 	/* Set the DTR and RTS pins low */
375 	cp2101_tiocmset(tty, NULL, TIOCM_DTR | TIOCM_RTS, 0);
376 
377 	return 0;
378 }
379 
380 static void cp2101_cleanup(struct usb_serial_port *port)
381 {
382 	struct usb_serial *serial = port->serial;
383 
384 	dbg("%s - port %d", __func__, port->number);
385 
386 	if (serial->dev) {
387 		/* shutdown any bulk reads that might be going on */
388 		if (serial->num_bulk_out)
389 			usb_kill_urb(port->write_urb);
390 		if (serial->num_bulk_in)
391 			usb_kill_urb(port->read_urb);
392 	}
393 }
394 
395 static void cp2101_close(struct tty_struct *tty, struct usb_serial_port *port,
396 					struct file *filp)
397 {
398 	dbg("%s - port %d", __func__, port->number);
399 
400 	/* shutdown our urbs */
401 	dbg("%s - shutting down urbs", __func__);
402 	usb_kill_urb(port->write_urb);
403 	usb_kill_urb(port->read_urb);
404 
405 	mutex_lock(&port->serial->disc_mutex);
406 	if (!port->serial->disconnected)
407 		cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
408 	mutex_unlock(&port->serial->disc_mutex);
409 }
410 
411 /*
412  * cp2101_get_termios
413  * Reads the baud rate, data bits, parity, stop bits and flow control mode
414  * from the device, corrects any unsupported values, and configures the
415  * termios structure to reflect the state of the device
416  */
417 static void cp2101_get_termios (struct tty_struct *tty)
418 {
419 	struct usb_serial_port *port = tty->driver_data;
420 	unsigned int cflag, modem_ctl[4];
421 	unsigned int baud;
422 	unsigned int bits;
423 
424 	dbg("%s - port %d", __func__, port->number);
425 
426 	cp2101_get_config(port, CP2101_BAUDRATE, &baud, 2);
427 	/* Convert to baudrate */
428 	if (baud)
429 		baud = cp2101_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
430 
431 	dbg("%s - baud rate = %d", __func__, baud);
432 
433 	tty_encode_baud_rate(tty, baud, baud);
434 	cflag = tty->termios->c_cflag;
435 
436 	cp2101_get_config(port, CP2101_BITS, &bits, 2);
437 	cflag &= ~CSIZE;
438 	switch (bits & BITS_DATA_MASK) {
439 	case BITS_DATA_5:
440 		dbg("%s - data bits = 5", __func__);
441 		cflag |= CS5;
442 		break;
443 	case BITS_DATA_6:
444 		dbg("%s - data bits = 6", __func__);
445 		cflag |= CS6;
446 		break;
447 	case BITS_DATA_7:
448 		dbg("%s - data bits = 7", __func__);
449 		cflag |= CS7;
450 		break;
451 	case BITS_DATA_8:
452 		dbg("%s - data bits = 8", __func__);
453 		cflag |= CS8;
454 		break;
455 	case BITS_DATA_9:
456 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
457 								__func__);
458 		cflag |= CS8;
459 		bits &= ~BITS_DATA_MASK;
460 		bits |= BITS_DATA_8;
461 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
462 		break;
463 	default:
464 		dbg("%s - Unknown number of data bits, using 8", __func__);
465 		cflag |= CS8;
466 		bits &= ~BITS_DATA_MASK;
467 		bits |= BITS_DATA_8;
468 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
469 		break;
470 	}
471 
472 	switch (bits & BITS_PARITY_MASK) {
473 	case BITS_PARITY_NONE:
474 		dbg("%s - parity = NONE", __func__);
475 		cflag &= ~PARENB;
476 		break;
477 	case BITS_PARITY_ODD:
478 		dbg("%s - parity = ODD", __func__);
479 		cflag |= (PARENB|PARODD);
480 		break;
481 	case BITS_PARITY_EVEN:
482 		dbg("%s - parity = EVEN", __func__);
483 		cflag &= ~PARODD;
484 		cflag |= PARENB;
485 		break;
486 	case BITS_PARITY_MARK:
487 		dbg("%s - parity = MARK (not supported, disabling parity)",
488 				__func__);
489 		cflag &= ~PARENB;
490 		bits &= ~BITS_PARITY_MASK;
491 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
492 		break;
493 	case BITS_PARITY_SPACE:
494 		dbg("%s - parity = SPACE (not supported, disabling parity)",
495 				__func__);
496 		cflag &= ~PARENB;
497 		bits &= ~BITS_PARITY_MASK;
498 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
499 		break;
500 	default:
501 		dbg("%s - Unknown parity mode, disabling parity", __func__);
502 		cflag &= ~PARENB;
503 		bits &= ~BITS_PARITY_MASK;
504 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
505 		break;
506 	}
507 
508 	cflag &= ~CSTOPB;
509 	switch (bits & BITS_STOP_MASK) {
510 	case BITS_STOP_1:
511 		dbg("%s - stop bits = 1", __func__);
512 		break;
513 	case BITS_STOP_1_5:
514 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
515 								__func__);
516 		bits &= ~BITS_STOP_MASK;
517 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
518 		break;
519 	case BITS_STOP_2:
520 		dbg("%s - stop bits = 2", __func__);
521 		cflag |= CSTOPB;
522 		break;
523 	default:
524 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
525 								__func__);
526 		bits &= ~BITS_STOP_MASK;
527 		cp2101_set_config(port, CP2101_BITS, &bits, 2);
528 		break;
529 	}
530 
531 	cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
532 	if (modem_ctl[0] & 0x0008) {
533 		dbg("%s - flow control = CRTSCTS", __func__);
534 		cflag |= CRTSCTS;
535 	} else {
536 		dbg("%s - flow control = NONE", __func__);
537 		cflag &= ~CRTSCTS;
538 	}
539 
540 	tty->termios->c_cflag = cflag;
541 }
542 
543 static void cp2101_set_termios(struct tty_struct *tty,
544 		struct usb_serial_port *port, struct ktermios *old_termios)
545 {
546 	unsigned int cflag, old_cflag;
547 	unsigned int baud = 0, bits;
548 	unsigned int modem_ctl[4];
549 
550 	dbg("%s - port %d", __func__, port->number);
551 
552 	if (!tty)
553 		return;
554 
555 	tty->termios->c_cflag &= ~CMSPAR;
556 	cflag = tty->termios->c_cflag;
557 	old_cflag = old_termios->c_cflag;
558 	baud = cp2101_quantise_baudrate(tty_get_baud_rate(tty));
559 
560 	/* If the baud rate is to be updated*/
561 	if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
562 		dbg("%s - Setting baud rate to %d baud", __func__,
563 				baud);
564 		if (cp2101_set_config_single(port, CP2101_BAUDRATE,
565 					((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
566 			dbg("Baud rate requested not supported by device\n");
567 			baud = tty_termios_baud_rate(old_termios);
568 		}
569 	}
570 	/* Report back the resulting baud rate */
571 	tty_encode_baud_rate(tty, baud, baud);
572 
573 	/* If the number of data bits is to be updated */
574 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
575 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
576 		bits &= ~BITS_DATA_MASK;
577 		switch (cflag & CSIZE) {
578 		case CS5:
579 			bits |= BITS_DATA_5;
580 			dbg("%s - data bits = 5", __func__);
581 			break;
582 		case CS6:
583 			bits |= BITS_DATA_6;
584 			dbg("%s - data bits = 6", __func__);
585 			break;
586 		case CS7:
587 			bits |= BITS_DATA_7;
588 			dbg("%s - data bits = 7", __func__);
589 			break;
590 		case CS8:
591 			bits |= BITS_DATA_8;
592 			dbg("%s - data bits = 8", __func__);
593 			break;
594 		/*case CS9:
595 			bits |= BITS_DATA_9;
596 			dbg("%s - data bits = 9", __func__);
597 			break;*/
598 		default:
599 			dbg("cp2101 driver does not "
600 					"support the number of bits requested,"
601 					" using 8 bit mode\n");
602 				bits |= BITS_DATA_8;
603 				break;
604 		}
605 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
606 			dbg("Number of data bits requested "
607 					"not supported by device\n");
608 	}
609 
610 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
611 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
612 		bits &= ~BITS_PARITY_MASK;
613 		if (cflag & PARENB) {
614 			if (cflag & PARODD) {
615 				bits |= BITS_PARITY_ODD;
616 				dbg("%s - parity = ODD", __func__);
617 			} else {
618 				bits |= BITS_PARITY_EVEN;
619 				dbg("%s - parity = EVEN", __func__);
620 			}
621 		}
622 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
623 			dbg("Parity mode not supported "
624 					"by device\n");
625 	}
626 
627 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
628 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
629 		bits &= ~BITS_STOP_MASK;
630 		if (cflag & CSTOPB) {
631 			bits |= BITS_STOP_2;
632 			dbg("%s - stop bits = 2", __func__);
633 		} else {
634 			bits |= BITS_STOP_1;
635 			dbg("%s - stop bits = 1", __func__);
636 		}
637 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
638 			dbg("Number of stop bits requested "
639 					"not supported by device\n");
640 	}
641 
642 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
643 		cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
644 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
645 				__func__, modem_ctl[0], modem_ctl[1],
646 				modem_ctl[2], modem_ctl[3]);
647 
648 		if (cflag & CRTSCTS) {
649 			modem_ctl[0] &= ~0x7B;
650 			modem_ctl[0] |= 0x09;
651 			modem_ctl[1] = 0x80;
652 			dbg("%s - flow control = CRTSCTS", __func__);
653 		} else {
654 			modem_ctl[0] &= ~0x7B;
655 			modem_ctl[0] |= 0x01;
656 			modem_ctl[1] |= 0x40;
657 			dbg("%s - flow control = NONE", __func__);
658 		}
659 
660 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
661 				__func__, modem_ctl[0], modem_ctl[1],
662 				modem_ctl[2], modem_ctl[3]);
663 		cp2101_set_config(port, CP2101_MODEMCTL, modem_ctl, 16);
664 	}
665 
666 }
667 
668 static int cp2101_tiocmset (struct tty_struct *tty, struct file *file,
669 		unsigned int set, unsigned int clear)
670 {
671 	struct usb_serial_port *port = tty->driver_data;
672 	unsigned int control = 0;
673 
674 	dbg("%s - port %d", __func__, port->number);
675 
676 	if (set & TIOCM_RTS) {
677 		control |= CONTROL_RTS;
678 		control |= CONTROL_WRITE_RTS;
679 	}
680 	if (set & TIOCM_DTR) {
681 		control |= CONTROL_DTR;
682 		control |= CONTROL_WRITE_DTR;
683 	}
684 	if (clear & TIOCM_RTS) {
685 		control &= ~CONTROL_RTS;
686 		control |= CONTROL_WRITE_RTS;
687 	}
688 	if (clear & TIOCM_DTR) {
689 		control &= ~CONTROL_DTR;
690 		control |= CONTROL_WRITE_DTR;
691 	}
692 
693 	dbg("%s - control = 0x%.4x", __func__, control);
694 
695 	return cp2101_set_config(port, CP2101_CONTROL, &control, 2);
696 
697 }
698 
699 static int cp2101_tiocmget (struct tty_struct *tty, struct file *file)
700 {
701 	struct usb_serial_port *port = tty->driver_data;
702 	unsigned int control;
703 	int result;
704 
705 	dbg("%s - port %d", __func__, port->number);
706 
707 	cp2101_get_config(port, CP2101_CONTROL, &control, 1);
708 
709 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
710 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
711 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
712 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
713 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
714 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
715 
716 	dbg("%s - control = 0x%.2x", __func__, control);
717 
718 	return result;
719 }
720 
721 static void cp2101_break_ctl (struct tty_struct *tty, int break_state)
722 {
723 	struct usb_serial_port *port = tty->driver_data;
724 	unsigned int state;
725 
726 	dbg("%s - port %d", __func__, port->number);
727 	if (break_state == 0)
728 		state = BREAK_OFF;
729 	else
730 		state = BREAK_ON;
731 	dbg("%s - turning break %s", __func__,
732 			state == BREAK_OFF ? "off" : "on");
733 	cp2101_set_config(port, CP2101_BREAK, &state, 2);
734 }
735 
736 static int cp2101_startup(struct usb_serial *serial)
737 {
738 	/* CP2101 buffers behave strangely unless device is reset */
739 	usb_reset_device(serial->dev);
740 	return 0;
741 }
742 
743 static void cp2101_shutdown(struct usb_serial *serial)
744 {
745 	int i;
746 
747 	dbg("%s", __func__);
748 
749 	/* Stop reads and writes on all ports */
750 	for (i = 0; i < serial->num_ports; ++i)
751 		cp2101_cleanup(serial->port[i]);
752 }
753 
754 static int __init cp2101_init(void)
755 {
756 	int retval;
757 
758 	retval = usb_serial_register(&cp2101_device);
759 	if (retval)
760 		return retval; /* Failed to register */
761 
762 	retval = usb_register(&cp2101_driver);
763 	if (retval) {
764 		/* Failed to register */
765 		usb_serial_deregister(&cp2101_device);
766 		return retval;
767 	}
768 
769 	/* Success */
770 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
771 	       DRIVER_DESC "\n");
772 	return 0;
773 }
774 
775 static void __exit cp2101_exit(void)
776 {
777 	usb_deregister(&cp2101_driver);
778 	usb_serial_deregister(&cp2101_device);
779 }
780 
781 module_init(cp2101_init);
782 module_exit(cp2101_exit);
783 
784 MODULE_DESCRIPTION(DRIVER_DESC);
785 MODULE_VERSION(DRIVER_VERSION);
786 MODULE_LICENSE("GPL");
787 
788 module_param(debug, bool, S_IRUGO | S_IWUSR);
789 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
790