xref: /linux/drivers/usb/serial/cp210x.c (revision 541e05ec3add5ab5bcf238d60161b53480280b20)
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, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
92 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
93 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
94 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
95 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
96 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
97 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
98 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
99 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
100 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
101 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
102 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
103 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
104 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
105 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesys ETRX2USB */
106 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
107 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
108 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
109 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
110 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
111 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
112 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
113 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
114 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
115 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
116 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
117 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
118 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
119 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
120 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
121 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
122 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
123 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
124 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
125 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
126 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
127 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
128 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
129 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
130 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
131 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
132 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
133 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
134 	{ } /* Terminating Entry */
135 };
136 
137 MODULE_DEVICE_TABLE(usb, id_table);
138 
139 static struct usb_driver cp210x_driver = {
140 	.name		= "cp210x",
141 	.probe		= usb_serial_probe,
142 	.disconnect	= usb_serial_disconnect,
143 	.id_table	= id_table,
144 	.no_dynamic_id	= 	1,
145 };
146 
147 static struct usb_serial_driver cp210x_device = {
148 	.driver = {
149 		.owner =	THIS_MODULE,
150 		.name = 	"cp210x",
151 	},
152 	.usb_driver		= &cp210x_driver,
153 	.id_table		= id_table,
154 	.num_ports		= 1,
155 	.bulk_in_size		= 256,
156 	.bulk_out_size		= 256,
157 	.open			= cp210x_open,
158 	.close			= cp210x_close,
159 	.break_ctl		= cp210x_break_ctl,
160 	.set_termios		= cp210x_set_termios,
161 	.tiocmget 		= cp210x_tiocmget,
162 	.tiocmset		= cp210x_tiocmset,
163 	.attach			= cp210x_startup,
164 	.dtr_rts		= cp210x_dtr_rts,
165 	.carrier_raised		= cp210x_carrier_raised
166 };
167 
168 /* Config request types */
169 #define REQTYPE_HOST_TO_DEVICE	0x41
170 #define REQTYPE_DEVICE_TO_HOST	0xc1
171 
172 /* Config request codes */
173 #define CP210X_IFC_ENABLE	0x00
174 #define CP210X_SET_BAUDDIV	0x01
175 #define CP210X_GET_BAUDDIV	0x02
176 #define CP210X_SET_LINE_CTL	0x03
177 #define CP210X_GET_LINE_CTL	0x04
178 #define CP210X_SET_BREAK	0x05
179 #define CP210X_IMM_CHAR		0x06
180 #define CP210X_SET_MHS		0x07
181 #define CP210X_GET_MDMSTS	0x08
182 #define CP210X_SET_XON		0x09
183 #define CP210X_SET_XOFF		0x0A
184 #define CP210X_SET_EVENTMASK	0x0B
185 #define CP210X_GET_EVENTMASK	0x0C
186 #define CP210X_SET_CHAR		0x0D
187 #define CP210X_GET_CHARS	0x0E
188 #define CP210X_GET_PROPS	0x0F
189 #define CP210X_GET_COMM_STATUS	0x10
190 #define CP210X_RESET		0x11
191 #define CP210X_PURGE		0x12
192 #define CP210X_SET_FLOW		0x13
193 #define CP210X_GET_FLOW		0x14
194 #define CP210X_EMBED_EVENTS	0x15
195 #define CP210X_GET_EVENTSTATE	0x16
196 #define CP210X_SET_CHARS	0x19
197 
198 /* CP210X_IFC_ENABLE */
199 #define UART_ENABLE		0x0001
200 #define UART_DISABLE		0x0000
201 
202 /* CP210X_(SET|GET)_BAUDDIV */
203 #define BAUD_RATE_GEN_FREQ	0x384000
204 
205 /* CP210X_(SET|GET)_LINE_CTL */
206 #define BITS_DATA_MASK		0X0f00
207 #define BITS_DATA_5		0X0500
208 #define BITS_DATA_6		0X0600
209 #define BITS_DATA_7		0X0700
210 #define BITS_DATA_8		0X0800
211 #define BITS_DATA_9		0X0900
212 
213 #define BITS_PARITY_MASK	0x00f0
214 #define BITS_PARITY_NONE	0x0000
215 #define BITS_PARITY_ODD		0x0010
216 #define BITS_PARITY_EVEN	0x0020
217 #define BITS_PARITY_MARK	0x0030
218 #define BITS_PARITY_SPACE	0x0040
219 
220 #define BITS_STOP_MASK		0x000f
221 #define BITS_STOP_1		0x0000
222 #define BITS_STOP_1_5		0x0001
223 #define BITS_STOP_2		0x0002
224 
225 /* CP210X_SET_BREAK */
226 #define BREAK_ON		0x0001
227 #define BREAK_OFF		0x0000
228 
229 /* CP210X_(SET_MHS|GET_MDMSTS) */
230 #define CONTROL_DTR		0x0001
231 #define CONTROL_RTS		0x0002
232 #define CONTROL_CTS		0x0010
233 #define CONTROL_DSR		0x0020
234 #define CONTROL_RING		0x0040
235 #define CONTROL_DCD		0x0080
236 #define CONTROL_WRITE_DTR	0x0100
237 #define CONTROL_WRITE_RTS	0x0200
238 
239 /*
240  * cp210x_get_config
241  * Reads from the CP210x configuration registers
242  * 'size' is specified in bytes.
243  * 'data' is a pointer to a pre-allocated array of integers large
244  * enough to hold 'size' bytes (with 4 bytes to each integer)
245  */
246 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
247 		unsigned int *data, int size)
248 {
249 	struct usb_serial *serial = port->serial;
250 	__le32 *buf;
251 	int result, i, length;
252 
253 	/* Number of integers required to contain the array */
254 	length = (((size - 1) | 3) + 1)/4;
255 
256 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
257 	if (!buf) {
258 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
259 		return -ENOMEM;
260 	}
261 
262 	/* Issue the request, attempting to read 'size' bytes */
263 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
264 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
265 				0, buf, size, 300);
266 
267 	/* Convert data into an array of integers */
268 	for (i = 0; i < length; i++)
269 		data[i] = le32_to_cpu(buf[i]);
270 
271 	kfree(buf);
272 
273 	if (result != size) {
274 		dbg("%s - Unable to send config request, "
275 				"request=0x%x size=%d result=%d\n",
276 				__func__, request, size, result);
277 		return -EPROTO;
278 	}
279 
280 	return 0;
281 }
282 
283 /*
284  * cp210x_set_config
285  * Writes to the CP210x configuration registers
286  * Values less than 16 bits wide are sent directly
287  * 'size' is specified in bytes.
288  */
289 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
290 		unsigned int *data, int size)
291 {
292 	struct usb_serial *serial = port->serial;
293 	__le32 *buf;
294 	int result, i, length;
295 
296 	/* Number of integers required to contain the array */
297 	length = (((size - 1) | 3) + 1)/4;
298 
299 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
300 	if (!buf) {
301 		dev_err(&port->dev, "%s - out of memory.\n",
302 				__func__);
303 		return -ENOMEM;
304 	}
305 
306 	/* Array of integers into bytes */
307 	for (i = 0; i < length; i++)
308 		buf[i] = cpu_to_le32(data[i]);
309 
310 	if (size > 2) {
311 		result = usb_control_msg(serial->dev,
312 				usb_sndctrlpipe(serial->dev, 0),
313 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
314 				0, buf, size, 300);
315 	} else {
316 		result = usb_control_msg(serial->dev,
317 				usb_sndctrlpipe(serial->dev, 0),
318 				request, REQTYPE_HOST_TO_DEVICE, data[0],
319 				0, NULL, 0, 300);
320 	}
321 
322 	kfree(buf);
323 
324 	if ((size > 2 && result != size) || result < 0) {
325 		dbg("%s - Unable to send request, "
326 				"request=0x%x size=%d result=%d\n",
327 				__func__, request, size, result);
328 		return -EPROTO;
329 	}
330 
331 	return 0;
332 }
333 
334 /*
335  * cp210x_set_config_single
336  * Convenience function for calling cp210x_set_config on single data values
337  * without requiring an integer pointer
338  */
339 static inline int cp210x_set_config_single(struct usb_serial_port *port,
340 		u8 request, unsigned int data)
341 {
342 	return cp210x_set_config(port, request, &data, 2);
343 }
344 
345 /*
346  * cp210x_quantise_baudrate
347  * Quantises the baud rate as per AN205 Table 1
348  */
349 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
350 	if      (baud <= 56)       baud = 0;
351 	else if (baud <= 300)      baud = 300;
352 	else if (baud <= 600)      baud = 600;
353 	else if (baud <= 1200)     baud = 1200;
354 	else if (baud <= 1800)     baud = 1800;
355 	else if (baud <= 2400)     baud = 2400;
356 	else if (baud <= 4000)     baud = 4000;
357 	else if (baud <= 4803)     baud = 4800;
358 	else if (baud <= 7207)     baud = 7200;
359 	else if (baud <= 9612)     baud = 9600;
360 	else if (baud <= 14428)    baud = 14400;
361 	else if (baud <= 16062)    baud = 16000;
362 	else if (baud <= 19250)    baud = 19200;
363 	else if (baud <= 28912)    baud = 28800;
364 	else if (baud <= 38601)    baud = 38400;
365 	else if (baud <= 51558)    baud = 51200;
366 	else if (baud <= 56280)    baud = 56000;
367 	else if (baud <= 58053)    baud = 57600;
368 	else if (baud <= 64111)    baud = 64000;
369 	else if (baud <= 77608)    baud = 76800;
370 	else if (baud <= 117028)   baud = 115200;
371 	else if (baud <= 129347)   baud = 128000;
372 	else if (baud <= 156868)   baud = 153600;
373 	else if (baud <= 237832)   baud = 230400;
374 	else if (baud <= 254234)   baud = 250000;
375 	else if (baud <= 273066)   baud = 256000;
376 	else if (baud <= 491520)   baud = 460800;
377 	else if (baud <= 567138)   baud = 500000;
378 	else if (baud <= 670254)   baud = 576000;
379 	else if (baud <= 1053257)  baud = 921600;
380 	else if (baud <= 1474560)  baud = 1228800;
381 	else if (baud <= 2457600)  baud = 1843200;
382 	else                       baud = 3686400;
383 	return baud;
384 }
385 
386 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
387 {
388 	int result;
389 
390 	dbg("%s - port %d", __func__, port->number);
391 
392 	if (cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_ENABLE)) {
393 		dev_err(&port->dev, "%s - Unable to enable UART\n",
394 				__func__);
395 		return -EPROTO;
396 	}
397 
398 	result = usb_serial_generic_open(tty, port);
399 	if (result)
400 		return result;
401 
402 	/* Configure the termios structure */
403 	cp210x_get_termios(tty, port);
404 	return 0;
405 }
406 
407 static void cp210x_close(struct usb_serial_port *port)
408 {
409 	dbg("%s - port %d", __func__, port->number);
410 
411 	usb_serial_generic_close(port);
412 
413 	mutex_lock(&port->serial->disc_mutex);
414 	if (!port->serial->disconnected)
415 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
416 	mutex_unlock(&port->serial->disc_mutex);
417 }
418 
419 /*
420  * cp210x_get_termios
421  * Reads the baud rate, data bits, parity, stop bits and flow control mode
422  * from the device, corrects any unsupported values, and configures the
423  * termios structure to reflect the state of the device
424  */
425 static void cp210x_get_termios(struct tty_struct *tty,
426 	struct usb_serial_port *port)
427 {
428 	unsigned int baud;
429 
430 	if (tty) {
431 		cp210x_get_termios_port(tty->driver_data,
432 			&tty->termios->c_cflag, &baud);
433 		tty_encode_baud_rate(tty, baud, baud);
434 	}
435 
436 	else {
437 		unsigned int cflag;
438 		cflag = 0;
439 		cp210x_get_termios_port(port, &cflag, &baud);
440 	}
441 }
442 
443 /*
444  * cp210x_get_termios_port
445  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
446  */
447 static void cp210x_get_termios_port(struct usb_serial_port *port,
448 	unsigned int *cflagp, unsigned int *baudp)
449 {
450 	unsigned int cflag, modem_ctl[4];
451 	unsigned int baud;
452 	unsigned int bits;
453 
454 	dbg("%s - port %d", __func__, port->number);
455 
456 	cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
457 	/* Convert to baudrate */
458 	if (baud)
459 		baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
460 
461 	dbg("%s - baud rate = %d", __func__, baud);
462 	*baudp = baud;
463 
464 	cflag = *cflagp;
465 
466 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
467 	cflag &= ~CSIZE;
468 	switch (bits & BITS_DATA_MASK) {
469 	case BITS_DATA_5:
470 		dbg("%s - data bits = 5", __func__);
471 		cflag |= CS5;
472 		break;
473 	case BITS_DATA_6:
474 		dbg("%s - data bits = 6", __func__);
475 		cflag |= CS6;
476 		break;
477 	case BITS_DATA_7:
478 		dbg("%s - data bits = 7", __func__);
479 		cflag |= CS7;
480 		break;
481 	case BITS_DATA_8:
482 		dbg("%s - data bits = 8", __func__);
483 		cflag |= CS8;
484 		break;
485 	case BITS_DATA_9:
486 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
487 								__func__);
488 		cflag |= CS8;
489 		bits &= ~BITS_DATA_MASK;
490 		bits |= BITS_DATA_8;
491 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
492 		break;
493 	default:
494 		dbg("%s - Unknown number of data bits, using 8", __func__);
495 		cflag |= CS8;
496 		bits &= ~BITS_DATA_MASK;
497 		bits |= BITS_DATA_8;
498 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
499 		break;
500 	}
501 
502 	switch (bits & BITS_PARITY_MASK) {
503 	case BITS_PARITY_NONE:
504 		dbg("%s - parity = NONE", __func__);
505 		cflag &= ~PARENB;
506 		break;
507 	case BITS_PARITY_ODD:
508 		dbg("%s - parity = ODD", __func__);
509 		cflag |= (PARENB|PARODD);
510 		break;
511 	case BITS_PARITY_EVEN:
512 		dbg("%s - parity = EVEN", __func__);
513 		cflag &= ~PARODD;
514 		cflag |= PARENB;
515 		break;
516 	case BITS_PARITY_MARK:
517 		dbg("%s - parity = MARK (not supported, disabling parity)",
518 				__func__);
519 		cflag &= ~PARENB;
520 		bits &= ~BITS_PARITY_MASK;
521 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
522 		break;
523 	case BITS_PARITY_SPACE:
524 		dbg("%s - parity = SPACE (not supported, disabling parity)",
525 				__func__);
526 		cflag &= ~PARENB;
527 		bits &= ~BITS_PARITY_MASK;
528 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
529 		break;
530 	default:
531 		dbg("%s - Unknown parity mode, disabling parity", __func__);
532 		cflag &= ~PARENB;
533 		bits &= ~BITS_PARITY_MASK;
534 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
535 		break;
536 	}
537 
538 	cflag &= ~CSTOPB;
539 	switch (bits & BITS_STOP_MASK) {
540 	case BITS_STOP_1:
541 		dbg("%s - stop bits = 1", __func__);
542 		break;
543 	case BITS_STOP_1_5:
544 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
545 								__func__);
546 		bits &= ~BITS_STOP_MASK;
547 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
548 		break;
549 	case BITS_STOP_2:
550 		dbg("%s - stop bits = 2", __func__);
551 		cflag |= CSTOPB;
552 		break;
553 	default:
554 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
555 								__func__);
556 		bits &= ~BITS_STOP_MASK;
557 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
558 		break;
559 	}
560 
561 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
562 	if (modem_ctl[0] & 0x0008) {
563 		dbg("%s - flow control = CRTSCTS", __func__);
564 		cflag |= CRTSCTS;
565 	} else {
566 		dbg("%s - flow control = NONE", __func__);
567 		cflag &= ~CRTSCTS;
568 	}
569 
570 	*cflagp = cflag;
571 }
572 
573 static void cp210x_set_termios(struct tty_struct *tty,
574 		struct usb_serial_port *port, struct ktermios *old_termios)
575 {
576 	unsigned int cflag, old_cflag;
577 	unsigned int baud = 0, bits;
578 	unsigned int modem_ctl[4];
579 
580 	dbg("%s - port %d", __func__, port->number);
581 
582 	if (!tty)
583 		return;
584 
585 	tty->termios->c_cflag &= ~CMSPAR;
586 	cflag = tty->termios->c_cflag;
587 	old_cflag = old_termios->c_cflag;
588 	baud = cp210x_quantise_baudrate(tty_get_baud_rate(tty));
589 
590 	/* If the baud rate is to be updated*/
591 	if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
592 		dbg("%s - Setting baud rate to %d baud", __func__,
593 				baud);
594 		if (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
595 					((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
596 			dbg("Baud rate requested not supported by device");
597 			baud = tty_termios_baud_rate(old_termios);
598 		}
599 	}
600 	/* Report back the resulting baud rate */
601 	tty_encode_baud_rate(tty, baud, baud);
602 
603 	/* If the number of data bits is to be updated */
604 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
605 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
606 		bits &= ~BITS_DATA_MASK;
607 		switch (cflag & CSIZE) {
608 		case CS5:
609 			bits |= BITS_DATA_5;
610 			dbg("%s - data bits = 5", __func__);
611 			break;
612 		case CS6:
613 			bits |= BITS_DATA_6;
614 			dbg("%s - data bits = 6", __func__);
615 			break;
616 		case CS7:
617 			bits |= BITS_DATA_7;
618 			dbg("%s - data bits = 7", __func__);
619 			break;
620 		case CS8:
621 			bits |= BITS_DATA_8;
622 			dbg("%s - data bits = 8", __func__);
623 			break;
624 		/*case CS9:
625 			bits |= BITS_DATA_9;
626 			dbg("%s - data bits = 9", __func__);
627 			break;*/
628 		default:
629 			dbg("cp210x driver does not "
630 					"support the number of bits requested,"
631 					" using 8 bit mode\n");
632 				bits |= BITS_DATA_8;
633 				break;
634 		}
635 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
636 			dbg("Number of data bits requested "
637 					"not supported by device\n");
638 	}
639 
640 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
641 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
642 		bits &= ~BITS_PARITY_MASK;
643 		if (cflag & PARENB) {
644 			if (cflag & PARODD) {
645 				bits |= BITS_PARITY_ODD;
646 				dbg("%s - parity = ODD", __func__);
647 			} else {
648 				bits |= BITS_PARITY_EVEN;
649 				dbg("%s - parity = EVEN", __func__);
650 			}
651 		}
652 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
653 			dbg("Parity mode not supported "
654 					"by device\n");
655 	}
656 
657 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
658 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
659 		bits &= ~BITS_STOP_MASK;
660 		if (cflag & CSTOPB) {
661 			bits |= BITS_STOP_2;
662 			dbg("%s - stop bits = 2", __func__);
663 		} else {
664 			bits |= BITS_STOP_1;
665 			dbg("%s - stop bits = 1", __func__);
666 		}
667 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
668 			dbg("Number of stop bits requested "
669 					"not supported by device\n");
670 	}
671 
672 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
673 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
674 		dbg("%s - read 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 
678 		if (cflag & CRTSCTS) {
679 			modem_ctl[0] &= ~0x7B;
680 			modem_ctl[0] |= 0x09;
681 			modem_ctl[1] = 0x80;
682 			dbg("%s - flow control = CRTSCTS", __func__);
683 		} else {
684 			modem_ctl[0] &= ~0x7B;
685 			modem_ctl[0] |= 0x01;
686 			modem_ctl[1] |= 0x40;
687 			dbg("%s - flow control = NONE", __func__);
688 		}
689 
690 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
691 				__func__, modem_ctl[0], modem_ctl[1],
692 				modem_ctl[2], modem_ctl[3]);
693 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
694 	}
695 
696 }
697 
698 static int cp210x_tiocmset (struct tty_struct *tty, struct file *file,
699 		unsigned int set, unsigned int clear)
700 {
701 	struct usb_serial_port *port = tty->driver_data;
702 	return cp210x_tiocmset_port(port, file, set, clear);
703 }
704 
705 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *file,
706 		unsigned int set, unsigned int clear)
707 {
708 	unsigned int control = 0;
709 
710 	dbg("%s - port %d", __func__, port->number);
711 
712 	if (set & TIOCM_RTS) {
713 		control |= CONTROL_RTS;
714 		control |= CONTROL_WRITE_RTS;
715 	}
716 	if (set & TIOCM_DTR) {
717 		control |= CONTROL_DTR;
718 		control |= CONTROL_WRITE_DTR;
719 	}
720 	if (clear & TIOCM_RTS) {
721 		control &= ~CONTROL_RTS;
722 		control |= CONTROL_WRITE_RTS;
723 	}
724 	if (clear & TIOCM_DTR) {
725 		control &= ~CONTROL_DTR;
726 		control |= CONTROL_WRITE_DTR;
727 	}
728 
729 	dbg("%s - control = 0x%.4x", __func__, control);
730 
731 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
732 }
733 
734 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
735 {
736 	if (on)
737 		cp210x_tiocmset_port(p, NULL,  TIOCM_DTR|TIOCM_RTS, 0);
738 	else
739 		cp210x_tiocmset_port(p, NULL,  0, TIOCM_DTR|TIOCM_RTS);
740 }
741 
742 static int cp210x_tiocmget (struct tty_struct *tty, struct file *file)
743 {
744 	struct usb_serial_port *port = tty->driver_data;
745 	unsigned int control;
746 	int result;
747 
748 	dbg("%s - port %d", __func__, port->number);
749 
750 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
751 
752 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
753 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
754 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
755 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
756 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
757 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
758 
759 	dbg("%s - control = 0x%.2x", __func__, control);
760 
761 	return result;
762 }
763 
764 static int cp210x_carrier_raised(struct usb_serial_port *p)
765 {
766 	unsigned int control;
767 	cp210x_get_config(p, CP210X_GET_MDMSTS, &control, 1);
768 	if (control & CONTROL_DCD)
769 		return 1;
770 	return 0;
771 }
772 
773 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
774 {
775 	struct usb_serial_port *port = tty->driver_data;
776 	unsigned int state;
777 
778 	dbg("%s - port %d", __func__, port->number);
779 	if (break_state == 0)
780 		state = BREAK_OFF;
781 	else
782 		state = BREAK_ON;
783 	dbg("%s - turning break %s", __func__,
784 			state == BREAK_OFF ? "off" : "on");
785 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
786 }
787 
788 static int cp210x_startup(struct usb_serial *serial)
789 {
790 	/* cp210x buffers behave strangely unless device is reset */
791 	usb_reset_device(serial->dev);
792 	return 0;
793 }
794 
795 static int __init cp210x_init(void)
796 {
797 	int retval;
798 
799 	retval = usb_serial_register(&cp210x_device);
800 	if (retval)
801 		return retval; /* Failed to register */
802 
803 	retval = usb_register(&cp210x_driver);
804 	if (retval) {
805 		/* Failed to register */
806 		usb_serial_deregister(&cp210x_device);
807 		return retval;
808 	}
809 
810 	/* Success */
811 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
812 	       DRIVER_DESC "\n");
813 	return 0;
814 }
815 
816 static void __exit cp210x_exit(void)
817 {
818 	usb_deregister(&cp210x_driver);
819 	usb_serial_deregister(&cp210x_device);
820 }
821 
822 module_init(cp210x_init);
823 module_exit(cp210x_exit);
824 
825 MODULE_DESCRIPTION(DRIVER_DESC);
826 MODULE_VERSION(DRIVER_VERSION);
827 MODULE_LICENSE("GPL");
828 
829 module_param(debug, bool, S_IRUGO | S_IWUSR);
830 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
831