xref: /linux/drivers/usb/serial/cp210x.c (revision a90131763dfd9a95f43071f0b67a737e6ca6a6c0)
1 /*
2  * Silicon Laboratories CP210x 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 "v0.09"
31 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
32 
33 /*
34  * Function Prototypes
35  */
36 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
37 static void cp210x_close(struct usb_serial_port *);
38 static void cp210x_get_termios(struct tty_struct *,
39 	struct usb_serial_port *port);
40 static void cp210x_get_termios_port(struct usb_serial_port *port,
41 	unsigned int *cflagp, unsigned int *baudp);
42 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
43 							struct ktermios*);
44 static int cp210x_tiocmget(struct tty_struct *, struct file *);
45 static int cp210x_tiocmset(struct tty_struct *, struct file *,
46 		unsigned int, unsigned int);
47 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *,
48 		unsigned int, unsigned int);
49 static void cp210x_break_ctl(struct tty_struct *, int);
50 static int cp210x_startup(struct usb_serial *);
51 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
52 static int cp210x_carrier_raised(struct usb_serial_port *p);
53 
54 static int debug;
55 
56 static const struct usb_device_id id_table[] = {
57 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
58 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
59 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
60 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
61 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
62 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
63 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
64 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
65 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
66 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
67 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
68 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
69 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
70 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
71 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
72 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
73 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
74 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
75 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
76 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
77 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
78 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
79 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
80 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
81 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
82 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
83 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
84 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
85 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
86 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
87 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
88 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
89 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
90 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
91 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
92 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
93 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
94 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
95 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
96 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
97 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesys ETRX2USB */
98 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
99 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
100 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
101 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
102 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
103 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
104 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
105 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
106 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
107 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
108 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
109 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
110 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
111 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
112 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
113 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
114 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
115 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
116 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
117 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
118 	{ } /* Terminating Entry */
119 };
120 
121 MODULE_DEVICE_TABLE(usb, id_table);
122 
123 static struct usb_driver cp210x_driver = {
124 	.name		= "cp210x",
125 	.probe		= usb_serial_probe,
126 	.disconnect	= usb_serial_disconnect,
127 	.id_table	= id_table,
128 	.no_dynamic_id	= 	1,
129 };
130 
131 static struct usb_serial_driver cp210x_device = {
132 	.driver = {
133 		.owner =	THIS_MODULE,
134 		.name = 	"cp210x",
135 	},
136 	.usb_driver		= &cp210x_driver,
137 	.id_table		= id_table,
138 	.num_ports		= 1,
139 	.bulk_in_size		= 256,
140 	.bulk_out_size		= 256,
141 	.open			= cp210x_open,
142 	.close			= cp210x_close,
143 	.break_ctl		= cp210x_break_ctl,
144 	.set_termios		= cp210x_set_termios,
145 	.tiocmget 		= cp210x_tiocmget,
146 	.tiocmset		= cp210x_tiocmset,
147 	.attach			= cp210x_startup,
148 	.dtr_rts		= cp210x_dtr_rts,
149 	.carrier_raised		= cp210x_carrier_raised
150 };
151 
152 /* Config request types */
153 #define REQTYPE_HOST_TO_DEVICE	0x41
154 #define REQTYPE_DEVICE_TO_HOST	0xc1
155 
156 /* Config request codes */
157 #define CP210X_IFC_ENABLE	0x00
158 #define CP210X_SET_BAUDDIV	0x01
159 #define CP210X_GET_BAUDDIV	0x02
160 #define CP210X_SET_LINE_CTL	0x03
161 #define CP210X_GET_LINE_CTL	0x04
162 #define CP210X_SET_BREAK	0x05
163 #define CP210X_IMM_CHAR		0x06
164 #define CP210X_SET_MHS		0x07
165 #define CP210X_GET_MDMSTS	0x08
166 #define CP210X_SET_XON		0x09
167 #define CP210X_SET_XOFF		0x0A
168 #define CP210X_SET_EVENTMASK	0x0B
169 #define CP210X_GET_EVENTMASK	0x0C
170 #define CP210X_SET_CHAR		0x0D
171 #define CP210X_GET_CHARS	0x0E
172 #define CP210X_GET_PROPS	0x0F
173 #define CP210X_GET_COMM_STATUS	0x10
174 #define CP210X_RESET		0x11
175 #define CP210X_PURGE		0x12
176 #define CP210X_SET_FLOW		0x13
177 #define CP210X_GET_FLOW		0x14
178 #define CP210X_EMBED_EVENTS	0x15
179 #define CP210X_GET_EVENTSTATE	0x16
180 #define CP210X_SET_CHARS	0x19
181 
182 /* CP210X_IFC_ENABLE */
183 #define UART_ENABLE		0x0001
184 #define UART_DISABLE		0x0000
185 
186 /* CP210X_(SET|GET)_BAUDDIV */
187 #define BAUD_RATE_GEN_FREQ	0x384000
188 
189 /* CP210X_(SET|GET)_LINE_CTL */
190 #define BITS_DATA_MASK		0X0f00
191 #define BITS_DATA_5		0X0500
192 #define BITS_DATA_6		0X0600
193 #define BITS_DATA_7		0X0700
194 #define BITS_DATA_8		0X0800
195 #define BITS_DATA_9		0X0900
196 
197 #define BITS_PARITY_MASK	0x00f0
198 #define BITS_PARITY_NONE	0x0000
199 #define BITS_PARITY_ODD		0x0010
200 #define BITS_PARITY_EVEN	0x0020
201 #define BITS_PARITY_MARK	0x0030
202 #define BITS_PARITY_SPACE	0x0040
203 
204 #define BITS_STOP_MASK		0x000f
205 #define BITS_STOP_1		0x0000
206 #define BITS_STOP_1_5		0x0001
207 #define BITS_STOP_2		0x0002
208 
209 /* CP210X_SET_BREAK */
210 #define BREAK_ON		0x0000
211 #define BREAK_OFF		0x0001
212 
213 /* CP210X_(SET_MHS|GET_MDMSTS) */
214 #define CONTROL_DTR		0x0001
215 #define CONTROL_RTS		0x0002
216 #define CONTROL_CTS		0x0010
217 #define CONTROL_DSR		0x0020
218 #define CONTROL_RING		0x0040
219 #define CONTROL_DCD		0x0080
220 #define CONTROL_WRITE_DTR	0x0100
221 #define CONTROL_WRITE_RTS	0x0200
222 
223 /*
224  * cp210x_get_config
225  * Reads from the CP210x configuration registers
226  * 'size' is specified in bytes.
227  * 'data' is a pointer to a pre-allocated array of integers large
228  * enough to hold 'size' bytes (with 4 bytes to each integer)
229  */
230 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
231 		unsigned int *data, int size)
232 {
233 	struct usb_serial *serial = port->serial;
234 	__le32 *buf;
235 	int result, i, length;
236 
237 	/* Number of integers required to contain the array */
238 	length = (((size - 1) | 3) + 1)/4;
239 
240 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
241 	if (!buf) {
242 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
243 		return -ENOMEM;
244 	}
245 
246 	/* Issue the request, attempting to read 'size' bytes */
247 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
248 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
249 				0, buf, size, 300);
250 
251 	/* Convert data into an array of integers */
252 	for (i = 0; i < length; i++)
253 		data[i] = le32_to_cpu(buf[i]);
254 
255 	kfree(buf);
256 
257 	if (result != size) {
258 		dbg("%s - Unable to send config request, "
259 				"request=0x%x size=%d result=%d\n",
260 				__func__, request, size, result);
261 		return -EPROTO;
262 	}
263 
264 	return 0;
265 }
266 
267 /*
268  * cp210x_set_config
269  * Writes to the CP210x configuration registers
270  * Values less than 16 bits wide are sent directly
271  * 'size' is specified in bytes.
272  */
273 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
274 		unsigned int *data, int size)
275 {
276 	struct usb_serial *serial = port->serial;
277 	__le32 *buf;
278 	int result, i, length;
279 
280 	/* Number of integers required to contain the array */
281 	length = (((size - 1) | 3) + 1)/4;
282 
283 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
284 	if (!buf) {
285 		dev_err(&port->dev, "%s - out of memory.\n",
286 				__func__);
287 		return -ENOMEM;
288 	}
289 
290 	/* Array of integers into bytes */
291 	for (i = 0; i < length; i++)
292 		buf[i] = cpu_to_le32(data[i]);
293 
294 	if (size > 2) {
295 		result = usb_control_msg(serial->dev,
296 				usb_sndctrlpipe(serial->dev, 0),
297 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
298 				0, buf, size, 300);
299 	} else {
300 		result = usb_control_msg(serial->dev,
301 				usb_sndctrlpipe(serial->dev, 0),
302 				request, REQTYPE_HOST_TO_DEVICE, data[0],
303 				0, NULL, 0, 300);
304 	}
305 
306 	kfree(buf);
307 
308 	if ((size > 2 && result != size) || result < 0) {
309 		dbg("%s - Unable to send request, "
310 				"request=0x%x size=%d result=%d\n",
311 				__func__, request, size, result);
312 		return -EPROTO;
313 	}
314 
315 	return 0;
316 }
317 
318 /*
319  * cp210x_set_config_single
320  * Convenience function for calling cp210x_set_config on single data values
321  * without requiring an integer pointer
322  */
323 static inline int cp210x_set_config_single(struct usb_serial_port *port,
324 		u8 request, unsigned int data)
325 {
326 	return cp210x_set_config(port, request, &data, 2);
327 }
328 
329 /*
330  * cp210x_quantise_baudrate
331  * Quantises the baud rate as per AN205 Table 1
332  */
333 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
334 	if      (baud <= 56)       baud = 0;
335 	else if (baud <= 300)      baud = 300;
336 	else if (baud <= 600)      baud = 600;
337 	else if (baud <= 1200)     baud = 1200;
338 	else if (baud <= 1800)     baud = 1800;
339 	else if (baud <= 2400)     baud = 2400;
340 	else if (baud <= 4000)     baud = 4000;
341 	else if (baud <= 4803)     baud = 4800;
342 	else if (baud <= 7207)     baud = 7200;
343 	else if (baud <= 9612)     baud = 9600;
344 	else if (baud <= 14428)    baud = 14400;
345 	else if (baud <= 16062)    baud = 16000;
346 	else if (baud <= 19250)    baud = 19200;
347 	else if (baud <= 28912)    baud = 28800;
348 	else if (baud <= 38601)    baud = 38400;
349 	else if (baud <= 51558)    baud = 51200;
350 	else if (baud <= 56280)    baud = 56000;
351 	else if (baud <= 58053)    baud = 57600;
352 	else if (baud <= 64111)    baud = 64000;
353 	else if (baud <= 77608)    baud = 76800;
354 	else if (baud <= 117028)   baud = 115200;
355 	else if (baud <= 129347)   baud = 128000;
356 	else if (baud <= 156868)   baud = 153600;
357 	else if (baud <= 237832)   baud = 230400;
358 	else if (baud <= 254234)   baud = 250000;
359 	else if (baud <= 273066)   baud = 256000;
360 	else if (baud <= 491520)   baud = 460800;
361 	else if (baud <= 567138)   baud = 500000;
362 	else if (baud <= 670254)   baud = 576000;
363 	else if (baud <= 1053257)  baud = 921600;
364 	else if (baud <= 1474560)  baud = 1228800;
365 	else if (baud <= 2457600)  baud = 1843200;
366 	else                       baud = 3686400;
367 	return baud;
368 }
369 
370 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
371 {
372 	int result;
373 
374 	dbg("%s - port %d", __func__, port->number);
375 
376 	if (cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_ENABLE)) {
377 		dev_err(&port->dev, "%s - Unable to enable UART\n",
378 				__func__);
379 		return -EPROTO;
380 	}
381 
382 	result = usb_serial_generic_open(tty, port);
383 	if (result)
384 		return result;
385 
386 	/* Configure the termios structure */
387 	cp210x_get_termios(tty, port);
388 	return 0;
389 }
390 
391 static void cp210x_close(struct usb_serial_port *port)
392 {
393 	dbg("%s - port %d", __func__, port->number);
394 
395 	usb_serial_generic_close(port);
396 
397 	mutex_lock(&port->serial->disc_mutex);
398 	if (!port->serial->disconnected)
399 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
400 	mutex_unlock(&port->serial->disc_mutex);
401 }
402 
403 /*
404  * cp210x_get_termios
405  * Reads the baud rate, data bits, parity, stop bits and flow control mode
406  * from the device, corrects any unsupported values, and configures the
407  * termios structure to reflect the state of the device
408  */
409 static void cp210x_get_termios(struct tty_struct *tty,
410 	struct usb_serial_port *port)
411 {
412 	unsigned int baud;
413 
414 	if (tty) {
415 		cp210x_get_termios_port(tty->driver_data,
416 			&tty->termios->c_cflag, &baud);
417 		tty_encode_baud_rate(tty, baud, baud);
418 	}
419 
420 	else {
421 		unsigned int cflag;
422 		cflag = 0;
423 		cp210x_get_termios_port(port, &cflag, &baud);
424 	}
425 }
426 
427 /*
428  * cp210x_get_termios_port
429  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
430  */
431 static void cp210x_get_termios_port(struct usb_serial_port *port,
432 	unsigned int *cflagp, unsigned int *baudp)
433 {
434 	unsigned int cflag, modem_ctl[4];
435 	unsigned int baud;
436 	unsigned int bits;
437 
438 	dbg("%s - port %d", __func__, port->number);
439 
440 	cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
441 	/* Convert to baudrate */
442 	if (baud)
443 		baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
444 
445 	dbg("%s - baud rate = %d", __func__, baud);
446 	*baudp = baud;
447 
448 	cflag = *cflagp;
449 
450 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
451 	cflag &= ~CSIZE;
452 	switch (bits & BITS_DATA_MASK) {
453 	case BITS_DATA_5:
454 		dbg("%s - data bits = 5", __func__);
455 		cflag |= CS5;
456 		break;
457 	case BITS_DATA_6:
458 		dbg("%s - data bits = 6", __func__);
459 		cflag |= CS6;
460 		break;
461 	case BITS_DATA_7:
462 		dbg("%s - data bits = 7", __func__);
463 		cflag |= CS7;
464 		break;
465 	case BITS_DATA_8:
466 		dbg("%s - data bits = 8", __func__);
467 		cflag |= CS8;
468 		break;
469 	case BITS_DATA_9:
470 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
471 								__func__);
472 		cflag |= CS8;
473 		bits &= ~BITS_DATA_MASK;
474 		bits |= BITS_DATA_8;
475 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
476 		break;
477 	default:
478 		dbg("%s - Unknown number of data bits, using 8", __func__);
479 		cflag |= CS8;
480 		bits &= ~BITS_DATA_MASK;
481 		bits |= BITS_DATA_8;
482 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
483 		break;
484 	}
485 
486 	switch (bits & BITS_PARITY_MASK) {
487 	case BITS_PARITY_NONE:
488 		dbg("%s - parity = NONE", __func__);
489 		cflag &= ~PARENB;
490 		break;
491 	case BITS_PARITY_ODD:
492 		dbg("%s - parity = ODD", __func__);
493 		cflag |= (PARENB|PARODD);
494 		break;
495 	case BITS_PARITY_EVEN:
496 		dbg("%s - parity = EVEN", __func__);
497 		cflag &= ~PARODD;
498 		cflag |= PARENB;
499 		break;
500 	case BITS_PARITY_MARK:
501 		dbg("%s - parity = MARK (not supported, disabling parity)",
502 				__func__);
503 		cflag &= ~PARENB;
504 		bits &= ~BITS_PARITY_MASK;
505 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
506 		break;
507 	case BITS_PARITY_SPACE:
508 		dbg("%s - parity = SPACE (not supported, disabling parity)",
509 				__func__);
510 		cflag &= ~PARENB;
511 		bits &= ~BITS_PARITY_MASK;
512 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
513 		break;
514 	default:
515 		dbg("%s - Unknown parity mode, disabling parity", __func__);
516 		cflag &= ~PARENB;
517 		bits &= ~BITS_PARITY_MASK;
518 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
519 		break;
520 	}
521 
522 	cflag &= ~CSTOPB;
523 	switch (bits & BITS_STOP_MASK) {
524 	case BITS_STOP_1:
525 		dbg("%s - stop bits = 1", __func__);
526 		break;
527 	case BITS_STOP_1_5:
528 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
529 								__func__);
530 		bits &= ~BITS_STOP_MASK;
531 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
532 		break;
533 	case BITS_STOP_2:
534 		dbg("%s - stop bits = 2", __func__);
535 		cflag |= CSTOPB;
536 		break;
537 	default:
538 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
539 								__func__);
540 		bits &= ~BITS_STOP_MASK;
541 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
542 		break;
543 	}
544 
545 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
546 	if (modem_ctl[0] & 0x0008) {
547 		dbg("%s - flow control = CRTSCTS", __func__);
548 		cflag |= CRTSCTS;
549 	} else {
550 		dbg("%s - flow control = NONE", __func__);
551 		cflag &= ~CRTSCTS;
552 	}
553 
554 	*cflagp = cflag;
555 }
556 
557 static void cp210x_set_termios(struct tty_struct *tty,
558 		struct usb_serial_port *port, struct ktermios *old_termios)
559 {
560 	unsigned int cflag, old_cflag;
561 	unsigned int baud = 0, bits;
562 	unsigned int modem_ctl[4];
563 
564 	dbg("%s - port %d", __func__, port->number);
565 
566 	if (!tty)
567 		return;
568 
569 	tty->termios->c_cflag &= ~CMSPAR;
570 	cflag = tty->termios->c_cflag;
571 	old_cflag = old_termios->c_cflag;
572 	baud = cp210x_quantise_baudrate(tty_get_baud_rate(tty));
573 
574 	/* If the baud rate is to be updated*/
575 	if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
576 		dbg("%s - Setting baud rate to %d baud", __func__,
577 				baud);
578 		if (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
579 					((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
580 			dbg("Baud rate requested not supported by device");
581 			baud = tty_termios_baud_rate(old_termios);
582 		}
583 	}
584 	/* Report back the resulting baud rate */
585 	tty_encode_baud_rate(tty, baud, baud);
586 
587 	/* If the number of data bits is to be updated */
588 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
589 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
590 		bits &= ~BITS_DATA_MASK;
591 		switch (cflag & CSIZE) {
592 		case CS5:
593 			bits |= BITS_DATA_5;
594 			dbg("%s - data bits = 5", __func__);
595 			break;
596 		case CS6:
597 			bits |= BITS_DATA_6;
598 			dbg("%s - data bits = 6", __func__);
599 			break;
600 		case CS7:
601 			bits |= BITS_DATA_7;
602 			dbg("%s - data bits = 7", __func__);
603 			break;
604 		case CS8:
605 			bits |= BITS_DATA_8;
606 			dbg("%s - data bits = 8", __func__);
607 			break;
608 		/*case CS9:
609 			bits |= BITS_DATA_9;
610 			dbg("%s - data bits = 9", __func__);
611 			break;*/
612 		default:
613 			dbg("cp210x driver does not "
614 					"support the number of bits requested,"
615 					" using 8 bit mode\n");
616 				bits |= BITS_DATA_8;
617 				break;
618 		}
619 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
620 			dbg("Number of data bits requested "
621 					"not supported by device\n");
622 	}
623 
624 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
625 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
626 		bits &= ~BITS_PARITY_MASK;
627 		if (cflag & PARENB) {
628 			if (cflag & PARODD) {
629 				bits |= BITS_PARITY_ODD;
630 				dbg("%s - parity = ODD", __func__);
631 			} else {
632 				bits |= BITS_PARITY_EVEN;
633 				dbg("%s - parity = EVEN", __func__);
634 			}
635 		}
636 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
637 			dbg("Parity mode not supported "
638 					"by device\n");
639 	}
640 
641 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
642 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
643 		bits &= ~BITS_STOP_MASK;
644 		if (cflag & CSTOPB) {
645 			bits |= BITS_STOP_2;
646 			dbg("%s - stop bits = 2", __func__);
647 		} else {
648 			bits |= BITS_STOP_1;
649 			dbg("%s - stop bits = 1", __func__);
650 		}
651 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
652 			dbg("Number of stop bits requested "
653 					"not supported by device\n");
654 	}
655 
656 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
657 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
658 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
659 				__func__, modem_ctl[0], modem_ctl[1],
660 				modem_ctl[2], modem_ctl[3]);
661 
662 		if (cflag & CRTSCTS) {
663 			modem_ctl[0] &= ~0x7B;
664 			modem_ctl[0] |= 0x09;
665 			modem_ctl[1] = 0x80;
666 			dbg("%s - flow control = CRTSCTS", __func__);
667 		} else {
668 			modem_ctl[0] &= ~0x7B;
669 			modem_ctl[0] |= 0x01;
670 			modem_ctl[1] |= 0x40;
671 			dbg("%s - flow control = NONE", __func__);
672 		}
673 
674 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
675 				__func__, modem_ctl[0], modem_ctl[1],
676 				modem_ctl[2], modem_ctl[3]);
677 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
678 	}
679 
680 }
681 
682 static int cp210x_tiocmset (struct tty_struct *tty, struct file *file,
683 		unsigned int set, unsigned int clear)
684 {
685 	struct usb_serial_port *port = tty->driver_data;
686 	return cp210x_tiocmset_port(port, file, set, clear);
687 }
688 
689 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *file,
690 		unsigned int set, unsigned int clear)
691 {
692 	unsigned int control = 0;
693 
694 	dbg("%s - port %d", __func__, port->number);
695 
696 	if (set & TIOCM_RTS) {
697 		control |= CONTROL_RTS;
698 		control |= CONTROL_WRITE_RTS;
699 	}
700 	if (set & TIOCM_DTR) {
701 		control |= CONTROL_DTR;
702 		control |= CONTROL_WRITE_DTR;
703 	}
704 	if (clear & TIOCM_RTS) {
705 		control &= ~CONTROL_RTS;
706 		control |= CONTROL_WRITE_RTS;
707 	}
708 	if (clear & TIOCM_DTR) {
709 		control &= ~CONTROL_DTR;
710 		control |= CONTROL_WRITE_DTR;
711 	}
712 
713 	dbg("%s - control = 0x%.4x", __func__, control);
714 
715 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
716 }
717 
718 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
719 {
720 	if (on)
721 		cp210x_tiocmset_port(p, NULL,  TIOCM_DTR|TIOCM_RTS, 0);
722 	else
723 		cp210x_tiocmset_port(p, NULL,  0, TIOCM_DTR|TIOCM_RTS);
724 }
725 
726 static int cp210x_tiocmget (struct tty_struct *tty, struct file *file)
727 {
728 	struct usb_serial_port *port = tty->driver_data;
729 	unsigned int control;
730 	int result;
731 
732 	dbg("%s - port %d", __func__, port->number);
733 
734 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
735 
736 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
737 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
738 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
739 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
740 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
741 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
742 
743 	dbg("%s - control = 0x%.2x", __func__, control);
744 
745 	return result;
746 }
747 
748 static int cp210x_carrier_raised(struct usb_serial_port *p)
749 {
750 	unsigned int control;
751 	cp210x_get_config(p, CP210X_GET_MDMSTS, &control, 1);
752 	if (control & CONTROL_DCD)
753 		return 1;
754 	return 0;
755 }
756 
757 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
758 {
759 	struct usb_serial_port *port = tty->driver_data;
760 	unsigned int state;
761 
762 	dbg("%s - port %d", __func__, port->number);
763 	if (break_state == 0)
764 		state = BREAK_OFF;
765 	else
766 		state = BREAK_ON;
767 	dbg("%s - turning break %s", __func__,
768 			state == BREAK_OFF ? "off" : "on");
769 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
770 }
771 
772 static int cp210x_startup(struct usb_serial *serial)
773 {
774 	/* cp210x buffers behave strangely unless device is reset */
775 	usb_reset_device(serial->dev);
776 	return 0;
777 }
778 
779 static int __init cp210x_init(void)
780 {
781 	int retval;
782 
783 	retval = usb_serial_register(&cp210x_device);
784 	if (retval)
785 		return retval; /* Failed to register */
786 
787 	retval = usb_register(&cp210x_driver);
788 	if (retval) {
789 		/* Failed to register */
790 		usb_serial_deregister(&cp210x_device);
791 		return retval;
792 	}
793 
794 	/* Success */
795 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
796 	       DRIVER_DESC "\n");
797 	return 0;
798 }
799 
800 static void __exit cp210x_exit(void)
801 {
802 	usb_deregister(&cp210x_driver);
803 	usb_serial_deregister(&cp210x_device);
804 }
805 
806 module_init(cp210x_init);
807 module_exit(cp210x_exit);
808 
809 MODULE_DESCRIPTION(DRIVER_DESC);
810 MODULE_VERSION(DRIVER_VERSION);
811 MODULE_LICENSE("GPL");
812 
813 module_param(debug, bool, S_IRUGO | S_IWUSR);
814 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
815