xref: /linux/drivers/usb/serial/cp210x.c (revision 0bf7a81c5d447c21db434be35363c44c0a30f598)
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(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
63 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
64 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
65 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
66 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
67 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
68 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
69 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
70 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
71 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
72 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
73 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
74 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
75 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
76 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
77 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
78 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
79 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
80 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
81 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
82 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
83 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
84 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
85 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
86 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
87 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
88 	{ USB_DEVICE(0x10C4, 0x8149) }, /* West Mountain Radio Computerized Battery Analyzer */
89 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
90 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
91 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
92 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
93 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
94 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
95 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
96 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
97 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
98 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
99 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
100 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
101 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
102 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
103 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
104 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
105 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
106 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesys ETRX2USB */
107 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
108 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
109 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
110 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
111 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
112 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
113 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
114 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
115 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
116 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
117 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
118 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
119 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
120 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
121 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
122 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
123 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
124 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
125 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
126 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
127 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
128 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
129 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
130 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
131 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
132 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
133 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
134 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
135 	{ } /* Terminating Entry */
136 };
137 
138 MODULE_DEVICE_TABLE(usb, id_table);
139 
140 static struct usb_driver cp210x_driver = {
141 	.name		= "cp210x",
142 	.probe		= usb_serial_probe,
143 	.disconnect	= usb_serial_disconnect,
144 	.id_table	= id_table,
145 	.no_dynamic_id	= 	1,
146 };
147 
148 static struct usb_serial_driver cp210x_device = {
149 	.driver = {
150 		.owner =	THIS_MODULE,
151 		.name = 	"cp210x",
152 	},
153 	.usb_driver		= &cp210x_driver,
154 	.id_table		= id_table,
155 	.num_ports		= 1,
156 	.bulk_in_size		= 256,
157 	.bulk_out_size		= 256,
158 	.open			= cp210x_open,
159 	.close			= cp210x_close,
160 	.break_ctl		= cp210x_break_ctl,
161 	.set_termios		= cp210x_set_termios,
162 	.tiocmget 		= cp210x_tiocmget,
163 	.tiocmset		= cp210x_tiocmset,
164 	.attach			= cp210x_startup,
165 	.dtr_rts		= cp210x_dtr_rts,
166 	.carrier_raised		= cp210x_carrier_raised
167 };
168 
169 /* Config request types */
170 #define REQTYPE_HOST_TO_DEVICE	0x41
171 #define REQTYPE_DEVICE_TO_HOST	0xc1
172 
173 /* Config request codes */
174 #define CP210X_IFC_ENABLE	0x00
175 #define CP210X_SET_BAUDDIV	0x01
176 #define CP210X_GET_BAUDDIV	0x02
177 #define CP210X_SET_LINE_CTL	0x03
178 #define CP210X_GET_LINE_CTL	0x04
179 #define CP210X_SET_BREAK	0x05
180 #define CP210X_IMM_CHAR		0x06
181 #define CP210X_SET_MHS		0x07
182 #define CP210X_GET_MDMSTS	0x08
183 #define CP210X_SET_XON		0x09
184 #define CP210X_SET_XOFF		0x0A
185 #define CP210X_SET_EVENTMASK	0x0B
186 #define CP210X_GET_EVENTMASK	0x0C
187 #define CP210X_SET_CHAR		0x0D
188 #define CP210X_GET_CHARS	0x0E
189 #define CP210X_GET_PROPS	0x0F
190 #define CP210X_GET_COMM_STATUS	0x10
191 #define CP210X_RESET		0x11
192 #define CP210X_PURGE		0x12
193 #define CP210X_SET_FLOW		0x13
194 #define CP210X_GET_FLOW		0x14
195 #define CP210X_EMBED_EVENTS	0x15
196 #define CP210X_GET_EVENTSTATE	0x16
197 #define CP210X_SET_CHARS	0x19
198 
199 /* CP210X_IFC_ENABLE */
200 #define UART_ENABLE		0x0001
201 #define UART_DISABLE		0x0000
202 
203 /* CP210X_(SET|GET)_BAUDDIV */
204 #define BAUD_RATE_GEN_FREQ	0x384000
205 
206 /* CP210X_(SET|GET)_LINE_CTL */
207 #define BITS_DATA_MASK		0X0f00
208 #define BITS_DATA_5		0X0500
209 #define BITS_DATA_6		0X0600
210 #define BITS_DATA_7		0X0700
211 #define BITS_DATA_8		0X0800
212 #define BITS_DATA_9		0X0900
213 
214 #define BITS_PARITY_MASK	0x00f0
215 #define BITS_PARITY_NONE	0x0000
216 #define BITS_PARITY_ODD		0x0010
217 #define BITS_PARITY_EVEN	0x0020
218 #define BITS_PARITY_MARK	0x0030
219 #define BITS_PARITY_SPACE	0x0040
220 
221 #define BITS_STOP_MASK		0x000f
222 #define BITS_STOP_1		0x0000
223 #define BITS_STOP_1_5		0x0001
224 #define BITS_STOP_2		0x0002
225 
226 /* CP210X_SET_BREAK */
227 #define BREAK_ON		0x0001
228 #define BREAK_OFF		0x0000
229 
230 /* CP210X_(SET_MHS|GET_MDMSTS) */
231 #define CONTROL_DTR		0x0001
232 #define CONTROL_RTS		0x0002
233 #define CONTROL_CTS		0x0010
234 #define CONTROL_DSR		0x0020
235 #define CONTROL_RING		0x0040
236 #define CONTROL_DCD		0x0080
237 #define CONTROL_WRITE_DTR	0x0100
238 #define CONTROL_WRITE_RTS	0x0200
239 
240 /*
241  * cp210x_get_config
242  * Reads from the CP210x configuration registers
243  * 'size' is specified in bytes.
244  * 'data' is a pointer to a pre-allocated array of integers large
245  * enough to hold 'size' bytes (with 4 bytes to each integer)
246  */
247 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
248 		unsigned int *data, int size)
249 {
250 	struct usb_serial *serial = port->serial;
251 	__le32 *buf;
252 	int result, i, length;
253 
254 	/* Number of integers required to contain the array */
255 	length = (((size - 1) | 3) + 1)/4;
256 
257 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
258 	if (!buf) {
259 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
260 		return -ENOMEM;
261 	}
262 
263 	/* Issue the request, attempting to read 'size' bytes */
264 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
265 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
266 				0, buf, size, 300);
267 
268 	/* Convert data into an array of integers */
269 	for (i = 0; i < length; i++)
270 		data[i] = le32_to_cpu(buf[i]);
271 
272 	kfree(buf);
273 
274 	if (result != size) {
275 		dbg("%s - Unable to send config request, "
276 				"request=0x%x size=%d result=%d\n",
277 				__func__, request, size, result);
278 		return -EPROTO;
279 	}
280 
281 	return 0;
282 }
283 
284 /*
285  * cp210x_set_config
286  * Writes to the CP210x configuration registers
287  * Values less than 16 bits wide are sent directly
288  * 'size' is specified in bytes.
289  */
290 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
291 		unsigned int *data, int size)
292 {
293 	struct usb_serial *serial = port->serial;
294 	__le32 *buf;
295 	int result, i, length;
296 
297 	/* Number of integers required to contain the array */
298 	length = (((size - 1) | 3) + 1)/4;
299 
300 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
301 	if (!buf) {
302 		dev_err(&port->dev, "%s - out of memory.\n",
303 				__func__);
304 		return -ENOMEM;
305 	}
306 
307 	/* Array of integers into bytes */
308 	for (i = 0; i < length; i++)
309 		buf[i] = cpu_to_le32(data[i]);
310 
311 	if (size > 2) {
312 		result = usb_control_msg(serial->dev,
313 				usb_sndctrlpipe(serial->dev, 0),
314 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
315 				0, buf, size, 300);
316 	} else {
317 		result = usb_control_msg(serial->dev,
318 				usb_sndctrlpipe(serial->dev, 0),
319 				request, REQTYPE_HOST_TO_DEVICE, data[0],
320 				0, NULL, 0, 300);
321 	}
322 
323 	kfree(buf);
324 
325 	if ((size > 2 && result != size) || result < 0) {
326 		dbg("%s - Unable to send request, "
327 				"request=0x%x size=%d result=%d\n",
328 				__func__, request, size, result);
329 		return -EPROTO;
330 	}
331 
332 	return 0;
333 }
334 
335 /*
336  * cp210x_set_config_single
337  * Convenience function for calling cp210x_set_config on single data values
338  * without requiring an integer pointer
339  */
340 static inline int cp210x_set_config_single(struct usb_serial_port *port,
341 		u8 request, unsigned int data)
342 {
343 	return cp210x_set_config(port, request, &data, 2);
344 }
345 
346 /*
347  * cp210x_quantise_baudrate
348  * Quantises the baud rate as per AN205 Table 1
349  */
350 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
351 	if      (baud <= 56)       baud = 0;
352 	else if (baud <= 300)      baud = 300;
353 	else if (baud <= 600)      baud = 600;
354 	else if (baud <= 1200)     baud = 1200;
355 	else if (baud <= 1800)     baud = 1800;
356 	else if (baud <= 2400)     baud = 2400;
357 	else if (baud <= 4000)     baud = 4000;
358 	else if (baud <= 4803)     baud = 4800;
359 	else if (baud <= 7207)     baud = 7200;
360 	else if (baud <= 9612)     baud = 9600;
361 	else if (baud <= 14428)    baud = 14400;
362 	else if (baud <= 16062)    baud = 16000;
363 	else if (baud <= 19250)    baud = 19200;
364 	else if (baud <= 28912)    baud = 28800;
365 	else if (baud <= 38601)    baud = 38400;
366 	else if (baud <= 51558)    baud = 51200;
367 	else if (baud <= 56280)    baud = 56000;
368 	else if (baud <= 58053)    baud = 57600;
369 	else if (baud <= 64111)    baud = 64000;
370 	else if (baud <= 77608)    baud = 76800;
371 	else if (baud <= 117028)   baud = 115200;
372 	else if (baud <= 129347)   baud = 128000;
373 	else if (baud <= 156868)   baud = 153600;
374 	else if (baud <= 237832)   baud = 230400;
375 	else if (baud <= 254234)   baud = 250000;
376 	else if (baud <= 273066)   baud = 256000;
377 	else if (baud <= 491520)   baud = 460800;
378 	else if (baud <= 567138)   baud = 500000;
379 	else if (baud <= 670254)   baud = 576000;
380 	else if (baud <= 1053257)  baud = 921600;
381 	else if (baud <= 1474560)  baud = 1228800;
382 	else if (baud <= 2457600)  baud = 1843200;
383 	else                       baud = 3686400;
384 	return baud;
385 }
386 
387 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
388 {
389 	int result;
390 
391 	dbg("%s - port %d", __func__, port->number);
392 
393 	if (cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_ENABLE)) {
394 		dev_err(&port->dev, "%s - Unable to enable UART\n",
395 				__func__);
396 		return -EPROTO;
397 	}
398 
399 	result = usb_serial_generic_open(tty, port);
400 	if (result)
401 		return result;
402 
403 	/* Configure the termios structure */
404 	cp210x_get_termios(tty, port);
405 	return 0;
406 }
407 
408 static void cp210x_close(struct usb_serial_port *port)
409 {
410 	dbg("%s - port %d", __func__, port->number);
411 
412 	usb_serial_generic_close(port);
413 
414 	mutex_lock(&port->serial->disc_mutex);
415 	if (!port->serial->disconnected)
416 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
417 	mutex_unlock(&port->serial->disc_mutex);
418 }
419 
420 /*
421  * cp210x_get_termios
422  * Reads the baud rate, data bits, parity, stop bits and flow control mode
423  * from the device, corrects any unsupported values, and configures the
424  * termios structure to reflect the state of the device
425  */
426 static void cp210x_get_termios(struct tty_struct *tty,
427 	struct usb_serial_port *port)
428 {
429 	unsigned int baud;
430 
431 	if (tty) {
432 		cp210x_get_termios_port(tty->driver_data,
433 			&tty->termios->c_cflag, &baud);
434 		tty_encode_baud_rate(tty, baud, baud);
435 	}
436 
437 	else {
438 		unsigned int cflag;
439 		cflag = 0;
440 		cp210x_get_termios_port(port, &cflag, &baud);
441 	}
442 }
443 
444 /*
445  * cp210x_get_termios_port
446  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
447  */
448 static void cp210x_get_termios_port(struct usb_serial_port *port,
449 	unsigned int *cflagp, unsigned int *baudp)
450 {
451 	unsigned int cflag, modem_ctl[4];
452 	unsigned int baud;
453 	unsigned int bits;
454 
455 	dbg("%s - port %d", __func__, port->number);
456 
457 	cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
458 	/* Convert to baudrate */
459 	if (baud)
460 		baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
461 
462 	dbg("%s - baud rate = %d", __func__, baud);
463 	*baudp = baud;
464 
465 	cflag = *cflagp;
466 
467 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
468 	cflag &= ~CSIZE;
469 	switch (bits & BITS_DATA_MASK) {
470 	case BITS_DATA_5:
471 		dbg("%s - data bits = 5", __func__);
472 		cflag |= CS5;
473 		break;
474 	case BITS_DATA_6:
475 		dbg("%s - data bits = 6", __func__);
476 		cflag |= CS6;
477 		break;
478 	case BITS_DATA_7:
479 		dbg("%s - data bits = 7", __func__);
480 		cflag |= CS7;
481 		break;
482 	case BITS_DATA_8:
483 		dbg("%s - data bits = 8", __func__);
484 		cflag |= CS8;
485 		break;
486 	case BITS_DATA_9:
487 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
488 								__func__);
489 		cflag |= CS8;
490 		bits &= ~BITS_DATA_MASK;
491 		bits |= BITS_DATA_8;
492 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
493 		break;
494 	default:
495 		dbg("%s - Unknown number of data bits, using 8", __func__);
496 		cflag |= CS8;
497 		bits &= ~BITS_DATA_MASK;
498 		bits |= BITS_DATA_8;
499 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
500 		break;
501 	}
502 
503 	switch (bits & BITS_PARITY_MASK) {
504 	case BITS_PARITY_NONE:
505 		dbg("%s - parity = NONE", __func__);
506 		cflag &= ~PARENB;
507 		break;
508 	case BITS_PARITY_ODD:
509 		dbg("%s - parity = ODD", __func__);
510 		cflag |= (PARENB|PARODD);
511 		break;
512 	case BITS_PARITY_EVEN:
513 		dbg("%s - parity = EVEN", __func__);
514 		cflag &= ~PARODD;
515 		cflag |= PARENB;
516 		break;
517 	case BITS_PARITY_MARK:
518 		dbg("%s - parity = MARK (not supported, disabling parity)",
519 				__func__);
520 		cflag &= ~PARENB;
521 		bits &= ~BITS_PARITY_MASK;
522 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
523 		break;
524 	case BITS_PARITY_SPACE:
525 		dbg("%s - parity = SPACE (not supported, disabling parity)",
526 				__func__);
527 		cflag &= ~PARENB;
528 		bits &= ~BITS_PARITY_MASK;
529 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
530 		break;
531 	default:
532 		dbg("%s - Unknown parity mode, disabling parity", __func__);
533 		cflag &= ~PARENB;
534 		bits &= ~BITS_PARITY_MASK;
535 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
536 		break;
537 	}
538 
539 	cflag &= ~CSTOPB;
540 	switch (bits & BITS_STOP_MASK) {
541 	case BITS_STOP_1:
542 		dbg("%s - stop bits = 1", __func__);
543 		break;
544 	case BITS_STOP_1_5:
545 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
546 								__func__);
547 		bits &= ~BITS_STOP_MASK;
548 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
549 		break;
550 	case BITS_STOP_2:
551 		dbg("%s - stop bits = 2", __func__);
552 		cflag |= CSTOPB;
553 		break;
554 	default:
555 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
556 								__func__);
557 		bits &= ~BITS_STOP_MASK;
558 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
559 		break;
560 	}
561 
562 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
563 	if (modem_ctl[0] & 0x0008) {
564 		dbg("%s - flow control = CRTSCTS", __func__);
565 		cflag |= CRTSCTS;
566 	} else {
567 		dbg("%s - flow control = NONE", __func__);
568 		cflag &= ~CRTSCTS;
569 	}
570 
571 	*cflagp = cflag;
572 }
573 
574 static void cp210x_set_termios(struct tty_struct *tty,
575 		struct usb_serial_port *port, struct ktermios *old_termios)
576 {
577 	unsigned int cflag, old_cflag;
578 	unsigned int baud = 0, bits;
579 	unsigned int modem_ctl[4];
580 
581 	dbg("%s - port %d", __func__, port->number);
582 
583 	if (!tty)
584 		return;
585 
586 	tty->termios->c_cflag &= ~CMSPAR;
587 	cflag = tty->termios->c_cflag;
588 	old_cflag = old_termios->c_cflag;
589 	baud = cp210x_quantise_baudrate(tty_get_baud_rate(tty));
590 
591 	/* If the baud rate is to be updated*/
592 	if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
593 		dbg("%s - Setting baud rate to %d baud", __func__,
594 				baud);
595 		if (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
596 					((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
597 			dbg("Baud rate requested not supported by device");
598 			baud = tty_termios_baud_rate(old_termios);
599 		}
600 	}
601 	/* Report back the resulting baud rate */
602 	tty_encode_baud_rate(tty, baud, baud);
603 
604 	/* If the number of data bits is to be updated */
605 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
606 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
607 		bits &= ~BITS_DATA_MASK;
608 		switch (cflag & CSIZE) {
609 		case CS5:
610 			bits |= BITS_DATA_5;
611 			dbg("%s - data bits = 5", __func__);
612 			break;
613 		case CS6:
614 			bits |= BITS_DATA_6;
615 			dbg("%s - data bits = 6", __func__);
616 			break;
617 		case CS7:
618 			bits |= BITS_DATA_7;
619 			dbg("%s - data bits = 7", __func__);
620 			break;
621 		case CS8:
622 			bits |= BITS_DATA_8;
623 			dbg("%s - data bits = 8", __func__);
624 			break;
625 		/*case CS9:
626 			bits |= BITS_DATA_9;
627 			dbg("%s - data bits = 9", __func__);
628 			break;*/
629 		default:
630 			dbg("cp210x driver does not "
631 					"support the number of bits requested,"
632 					" using 8 bit mode\n");
633 				bits |= BITS_DATA_8;
634 				break;
635 		}
636 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
637 			dbg("Number of data bits requested "
638 					"not supported by device\n");
639 	}
640 
641 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
642 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
643 		bits &= ~BITS_PARITY_MASK;
644 		if (cflag & PARENB) {
645 			if (cflag & PARODD) {
646 				bits |= BITS_PARITY_ODD;
647 				dbg("%s - parity = ODD", __func__);
648 			} else {
649 				bits |= BITS_PARITY_EVEN;
650 				dbg("%s - parity = EVEN", __func__);
651 			}
652 		}
653 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
654 			dbg("Parity mode not supported "
655 					"by device\n");
656 	}
657 
658 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
659 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
660 		bits &= ~BITS_STOP_MASK;
661 		if (cflag & CSTOPB) {
662 			bits |= BITS_STOP_2;
663 			dbg("%s - stop bits = 2", __func__);
664 		} else {
665 			bits |= BITS_STOP_1;
666 			dbg("%s - stop bits = 1", __func__);
667 		}
668 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
669 			dbg("Number of stop bits requested "
670 					"not supported by device\n");
671 	}
672 
673 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
674 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
675 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
676 				__func__, modem_ctl[0], modem_ctl[1],
677 				modem_ctl[2], modem_ctl[3]);
678 
679 		if (cflag & CRTSCTS) {
680 			modem_ctl[0] &= ~0x7B;
681 			modem_ctl[0] |= 0x09;
682 			modem_ctl[1] = 0x80;
683 			dbg("%s - flow control = CRTSCTS", __func__);
684 		} else {
685 			modem_ctl[0] &= ~0x7B;
686 			modem_ctl[0] |= 0x01;
687 			modem_ctl[1] |= 0x40;
688 			dbg("%s - flow control = NONE", __func__);
689 		}
690 
691 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
692 				__func__, modem_ctl[0], modem_ctl[1],
693 				modem_ctl[2], modem_ctl[3]);
694 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
695 	}
696 
697 }
698 
699 static int cp210x_tiocmset (struct tty_struct *tty, struct file *file,
700 		unsigned int set, unsigned int clear)
701 {
702 	struct usb_serial_port *port = tty->driver_data;
703 	return cp210x_tiocmset_port(port, file, set, clear);
704 }
705 
706 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *file,
707 		unsigned int set, unsigned int clear)
708 {
709 	unsigned int control = 0;
710 
711 	dbg("%s - port %d", __func__, port->number);
712 
713 	if (set & TIOCM_RTS) {
714 		control |= CONTROL_RTS;
715 		control |= CONTROL_WRITE_RTS;
716 	}
717 	if (set & TIOCM_DTR) {
718 		control |= CONTROL_DTR;
719 		control |= CONTROL_WRITE_DTR;
720 	}
721 	if (clear & TIOCM_RTS) {
722 		control &= ~CONTROL_RTS;
723 		control |= CONTROL_WRITE_RTS;
724 	}
725 	if (clear & TIOCM_DTR) {
726 		control &= ~CONTROL_DTR;
727 		control |= CONTROL_WRITE_DTR;
728 	}
729 
730 	dbg("%s - control = 0x%.4x", __func__, control);
731 
732 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
733 }
734 
735 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
736 {
737 	if (on)
738 		cp210x_tiocmset_port(p, NULL,  TIOCM_DTR|TIOCM_RTS, 0);
739 	else
740 		cp210x_tiocmset_port(p, NULL,  0, TIOCM_DTR|TIOCM_RTS);
741 }
742 
743 static int cp210x_tiocmget (struct tty_struct *tty, struct file *file)
744 {
745 	struct usb_serial_port *port = tty->driver_data;
746 	unsigned int control;
747 	int result;
748 
749 	dbg("%s - port %d", __func__, port->number);
750 
751 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
752 
753 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
754 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
755 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
756 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
757 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
758 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
759 
760 	dbg("%s - control = 0x%.2x", __func__, control);
761 
762 	return result;
763 }
764 
765 static int cp210x_carrier_raised(struct usb_serial_port *p)
766 {
767 	unsigned int control;
768 	cp210x_get_config(p, CP210X_GET_MDMSTS, &control, 1);
769 	if (control & CONTROL_DCD)
770 		return 1;
771 	return 0;
772 }
773 
774 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
775 {
776 	struct usb_serial_port *port = tty->driver_data;
777 	unsigned int state;
778 
779 	dbg("%s - port %d", __func__, port->number);
780 	if (break_state == 0)
781 		state = BREAK_OFF;
782 	else
783 		state = BREAK_ON;
784 	dbg("%s - turning break %s", __func__,
785 			state == BREAK_OFF ? "off" : "on");
786 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
787 }
788 
789 static int cp210x_startup(struct usb_serial *serial)
790 {
791 	/* cp210x buffers behave strangely unless device is reset */
792 	usb_reset_device(serial->dev);
793 	return 0;
794 }
795 
796 static int __init cp210x_init(void)
797 {
798 	int retval;
799 
800 	retval = usb_serial_register(&cp210x_device);
801 	if (retval)
802 		return retval; /* Failed to register */
803 
804 	retval = usb_register(&cp210x_driver);
805 	if (retval) {
806 		/* Failed to register */
807 		usb_serial_deregister(&cp210x_device);
808 		return retval;
809 	}
810 
811 	/* Success */
812 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
813 	       DRIVER_DESC "\n");
814 	return 0;
815 }
816 
817 static void __exit cp210x_exit(void)
818 {
819 	usb_deregister(&cp210x_driver);
820 	usb_serial_deregister(&cp210x_device);
821 }
822 
823 module_init(cp210x_init);
824 module_exit(cp210x_exit);
825 
826 MODULE_DESCRIPTION(DRIVER_DESC);
827 MODULE_VERSION(DRIVER_VERSION);
828 MODULE_LICENSE("GPL");
829 
830 module_param(debug, bool, S_IRUGO | S_IWUSR);
831 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
832