xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision e8e0929d)
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_cleanup(struct usb_serial_port *);
38 static void cp210x_close(struct usb_serial_port *);
39 static void cp210x_get_termios(struct tty_struct *,
40 	struct usb_serial_port *port);
41 static void cp210x_get_termios_port(struct usb_serial_port *port,
42 	unsigned int *cflagp, unsigned int *baudp);
43 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
44 							struct ktermios*);
45 static int cp210x_tiocmget(struct tty_struct *, struct file *);
46 static int cp210x_tiocmset(struct tty_struct *, struct file *,
47 		unsigned int, unsigned int);
48 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *,
49 		unsigned int, unsigned int);
50 static void cp210x_break_ctl(struct tty_struct *, int);
51 static int cp210x_startup(struct usb_serial *);
52 static void cp210x_disconnect(struct usb_serial *);
53 
54 static int debug;
55 
56 static 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, 0x81F2) }, /* C1007 HF band RFID controller */
93 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
94 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
95 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
96 	{ USB_DEVICE(0x10c4, 0x8293) }, /* Telegesys ETRX2USB */
97 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
98 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
99 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
100 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
101 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
102 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
103 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
104 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
105 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
106 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
107 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
108 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
109 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
110 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
111 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
112 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
113 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
114 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
115 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
116 	{ } /* Terminating Entry */
117 };
118 
119 MODULE_DEVICE_TABLE(usb, id_table);
120 
121 static struct usb_driver cp210x_driver = {
122 	.name		= "cp210x",
123 	.probe		= usb_serial_probe,
124 	.disconnect	= usb_serial_disconnect,
125 	.id_table	= id_table,
126 	.no_dynamic_id	= 	1,
127 };
128 
129 static struct usb_serial_driver cp210x_device = {
130 	.driver = {
131 		.owner =	THIS_MODULE,
132 		.name = 	"cp210x",
133 	},
134 	.usb_driver		= &cp210x_driver,
135 	.id_table		= id_table,
136 	.num_ports		= 1,
137 	.open			= cp210x_open,
138 	.close			= cp210x_close,
139 	.break_ctl		= cp210x_break_ctl,
140 	.set_termios		= cp210x_set_termios,
141 	.tiocmget 		= cp210x_tiocmget,
142 	.tiocmset		= cp210x_tiocmset,
143 	.attach			= cp210x_startup,
144 	.disconnect		= cp210x_disconnect,
145 };
146 
147 /* Config request types */
148 #define REQTYPE_HOST_TO_DEVICE	0x41
149 #define REQTYPE_DEVICE_TO_HOST	0xc1
150 
151 /* Config request codes */
152 #define CP210X_IFC_ENABLE	0x00
153 #define CP210X_SET_BAUDDIV	0x01
154 #define CP210X_GET_BAUDDIV	0x02
155 #define CP210X_SET_LINE_CTL	0x03
156 #define CP210X_GET_LINE_CTL	0x04
157 #define CP210X_SET_BREAK	0x05
158 #define CP210X_IMM_CHAR		0x06
159 #define CP210X_SET_MHS		0x07
160 #define CP210X_GET_MDMSTS	0x08
161 #define CP210X_SET_XON		0x09
162 #define CP210X_SET_XOFF		0x0A
163 #define CP210X_SET_EVENTMASK	0x0B
164 #define CP210X_GET_EVENTMASK	0x0C
165 #define CP210X_SET_CHAR		0x0D
166 #define CP210X_GET_CHARS	0x0E
167 #define CP210X_GET_PROPS	0x0F
168 #define CP210X_GET_COMM_STATUS	0x10
169 #define CP210X_RESET		0x11
170 #define CP210X_PURGE		0x12
171 #define CP210X_SET_FLOW		0x13
172 #define CP210X_GET_FLOW		0x14
173 #define CP210X_EMBED_EVENTS	0x15
174 #define CP210X_GET_EVENTSTATE	0x16
175 #define CP210X_SET_CHARS	0x19
176 
177 /* CP210X_IFC_ENABLE */
178 #define UART_ENABLE		0x0001
179 #define UART_DISABLE		0x0000
180 
181 /* CP210X_(SET|GET)_BAUDDIV */
182 #define BAUD_RATE_GEN_FREQ	0x384000
183 
184 /* CP210X_(SET|GET)_LINE_CTL */
185 #define BITS_DATA_MASK		0X0f00
186 #define BITS_DATA_5		0X0500
187 #define BITS_DATA_6		0X0600
188 #define BITS_DATA_7		0X0700
189 #define BITS_DATA_8		0X0800
190 #define BITS_DATA_9		0X0900
191 
192 #define BITS_PARITY_MASK	0x00f0
193 #define BITS_PARITY_NONE	0x0000
194 #define BITS_PARITY_ODD		0x0010
195 #define BITS_PARITY_EVEN	0x0020
196 #define BITS_PARITY_MARK	0x0030
197 #define BITS_PARITY_SPACE	0x0040
198 
199 #define BITS_STOP_MASK		0x000f
200 #define BITS_STOP_1		0x0000
201 #define BITS_STOP_1_5		0x0001
202 #define BITS_STOP_2		0x0002
203 
204 /* CP210X_SET_BREAK */
205 #define BREAK_ON		0x0000
206 #define BREAK_OFF		0x0001
207 
208 /* CP210X_(SET_MHS|GET_MDMSTS) */
209 #define CONTROL_DTR		0x0001
210 #define CONTROL_RTS		0x0002
211 #define CONTROL_CTS		0x0010
212 #define CONTROL_DSR		0x0020
213 #define CONTROL_RING		0x0040
214 #define CONTROL_DCD		0x0080
215 #define CONTROL_WRITE_DTR	0x0100
216 #define CONTROL_WRITE_RTS	0x0200
217 
218 /*
219  * cp210x_get_config
220  * Reads from the CP210x configuration registers
221  * 'size' is specified in bytes.
222  * 'data' is a pointer to a pre-allocated array of integers large
223  * enough to hold 'size' bytes (with 4 bytes to each integer)
224  */
225 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
226 		unsigned int *data, int size)
227 {
228 	struct usb_serial *serial = port->serial;
229 	__le32 *buf;
230 	int result, i, length;
231 
232 	/* Number of integers required to contain the array */
233 	length = (((size - 1) | 3) + 1)/4;
234 
235 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
236 	if (!buf) {
237 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
238 		return -ENOMEM;
239 	}
240 
241 	/* Issue the request, attempting to read 'size' bytes */
242 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
243 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
244 				0, buf, size, 300);
245 
246 	/* Convert data into an array of integers */
247 	for (i = 0; i < length; i++)
248 		data[i] = le32_to_cpu(buf[i]);
249 
250 	kfree(buf);
251 
252 	if (result != size) {
253 		dbg("%s - Unable to send config request, "
254 				"request=0x%x size=%d result=%d\n",
255 				__func__, request, size, result);
256 		return -EPROTO;
257 	}
258 
259 	return 0;
260 }
261 
262 /*
263  * cp210x_set_config
264  * Writes to the CP210x configuration registers
265  * Values less than 16 bits wide are sent directly
266  * 'size' is specified in bytes.
267  */
268 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
269 		unsigned int *data, int size)
270 {
271 	struct usb_serial *serial = port->serial;
272 	__le32 *buf;
273 	int result, i, length;
274 
275 	/* Number of integers required to contain the array */
276 	length = (((size - 1) | 3) + 1)/4;
277 
278 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
279 	if (!buf) {
280 		dev_err(&port->dev, "%s - out of memory.\n",
281 				__func__);
282 		return -ENOMEM;
283 	}
284 
285 	/* Array of integers into bytes */
286 	for (i = 0; i < length; i++)
287 		buf[i] = cpu_to_le32(data[i]);
288 
289 	if (size > 2) {
290 		result = usb_control_msg(serial->dev,
291 				usb_sndctrlpipe(serial->dev, 0),
292 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
293 				0, buf, size, 300);
294 	} else {
295 		result = usb_control_msg(serial->dev,
296 				usb_sndctrlpipe(serial->dev, 0),
297 				request, REQTYPE_HOST_TO_DEVICE, data[0],
298 				0, NULL, 0, 300);
299 	}
300 
301 	kfree(buf);
302 
303 	if ((size > 2 && result != size) || result < 0) {
304 		dbg("%s - Unable to send request, "
305 				"request=0x%x size=%d result=%d\n",
306 				__func__, request, size, result);
307 		return -EPROTO;
308 	}
309 
310 	/* Single data value */
311 	result = usb_control_msg(serial->dev,
312 			usb_sndctrlpipe(serial->dev, 0),
313 			request, REQTYPE_HOST_TO_DEVICE, data[0],
314 			0, NULL, 0, 300);
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 	struct usb_serial *serial = port->serial;
373 	int result;
374 
375 	dbg("%s - port %d", __func__, port->number);
376 
377 	if (cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_ENABLE)) {
378 		dev_err(&port->dev, "%s - Unable to enable UART\n",
379 				__func__);
380 		return -EPROTO;
381 	}
382 
383 	/* Start reading from the device */
384 	usb_fill_bulk_urb(port->read_urb, serial->dev,
385 			usb_rcvbulkpipe(serial->dev,
386 			port->bulk_in_endpointAddress),
387 			port->read_urb->transfer_buffer,
388 			port->read_urb->transfer_buffer_length,
389 			serial->type->read_bulk_callback,
390 			port);
391 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
392 	if (result) {
393 		dev_err(&port->dev, "%s - failed resubmitting read urb, "
394 				"error %d\n", __func__, result);
395 		return result;
396 	}
397 
398 	/* Configure the termios structure */
399 	cp210x_get_termios(tty, port);
400 	return 0;
401 }
402 
403 static void cp210x_cleanup(struct usb_serial_port *port)
404 {
405 	struct usb_serial *serial = port->serial;
406 
407 	dbg("%s - port %d", __func__, port->number);
408 
409 	if (serial->dev) {
410 		/* shutdown any bulk reads that might be going on */
411 		if (serial->num_bulk_out)
412 			usb_kill_urb(port->write_urb);
413 		if (serial->num_bulk_in)
414 			usb_kill_urb(port->read_urb);
415 	}
416 }
417 
418 static void cp210x_close(struct usb_serial_port *port)
419 {
420 	dbg("%s - port %d", __func__, port->number);
421 
422 	/* shutdown our urbs */
423 	dbg("%s - shutting down urbs", __func__);
424 	usb_kill_urb(port->write_urb);
425 	usb_kill_urb(port->read_urb);
426 
427 	mutex_lock(&port->serial->disc_mutex);
428 	if (!port->serial->disconnected)
429 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
430 	mutex_unlock(&port->serial->disc_mutex);
431 }
432 
433 /*
434  * cp210x_get_termios
435  * Reads the baud rate, data bits, parity, stop bits and flow control mode
436  * from the device, corrects any unsupported values, and configures the
437  * termios structure to reflect the state of the device
438  */
439 static void cp210x_get_termios(struct tty_struct *tty,
440 	struct usb_serial_port *port)
441 {
442 	unsigned int baud;
443 
444 	if (tty) {
445 		cp210x_get_termios_port(tty->driver_data,
446 			&tty->termios->c_cflag, &baud);
447 		tty_encode_baud_rate(tty, baud, baud);
448 	}
449 
450 	else {
451 		unsigned int cflag;
452 		cflag = 0;
453 		cp210x_get_termios_port(port, &cflag, &baud);
454 	}
455 }
456 
457 /*
458  * cp210x_get_termios_port
459  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
460  */
461 static void cp210x_get_termios_port(struct usb_serial_port *port,
462 	unsigned int *cflagp, unsigned int *baudp)
463 {
464 	unsigned int cflag, modem_ctl[4];
465 	unsigned int baud;
466 	unsigned int bits;
467 
468 	dbg("%s - port %d", __func__, port->number);
469 
470 	cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
471 	/* Convert to baudrate */
472 	if (baud)
473 		baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
474 
475 	dbg("%s - baud rate = %d", __func__, baud);
476 	*baudp = baud;
477 
478 	cflag = *cflagp;
479 
480 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
481 	cflag &= ~CSIZE;
482 	switch (bits & BITS_DATA_MASK) {
483 	case BITS_DATA_5:
484 		dbg("%s - data bits = 5", __func__);
485 		cflag |= CS5;
486 		break;
487 	case BITS_DATA_6:
488 		dbg("%s - data bits = 6", __func__);
489 		cflag |= CS6;
490 		break;
491 	case BITS_DATA_7:
492 		dbg("%s - data bits = 7", __func__);
493 		cflag |= CS7;
494 		break;
495 	case BITS_DATA_8:
496 		dbg("%s - data bits = 8", __func__);
497 		cflag |= CS8;
498 		break;
499 	case BITS_DATA_9:
500 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
501 								__func__);
502 		cflag |= CS8;
503 		bits &= ~BITS_DATA_MASK;
504 		bits |= BITS_DATA_8;
505 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
506 		break;
507 	default:
508 		dbg("%s - Unknown number of data bits, using 8", __func__);
509 		cflag |= CS8;
510 		bits &= ~BITS_DATA_MASK;
511 		bits |= BITS_DATA_8;
512 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
513 		break;
514 	}
515 
516 	switch (bits & BITS_PARITY_MASK) {
517 	case BITS_PARITY_NONE:
518 		dbg("%s - parity = NONE", __func__);
519 		cflag &= ~PARENB;
520 		break;
521 	case BITS_PARITY_ODD:
522 		dbg("%s - parity = ODD", __func__);
523 		cflag |= (PARENB|PARODD);
524 		break;
525 	case BITS_PARITY_EVEN:
526 		dbg("%s - parity = EVEN", __func__);
527 		cflag &= ~PARODD;
528 		cflag |= PARENB;
529 		break;
530 	case BITS_PARITY_MARK:
531 		dbg("%s - parity = MARK (not supported, disabling parity)",
532 				__func__);
533 		cflag &= ~PARENB;
534 		bits &= ~BITS_PARITY_MASK;
535 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
536 		break;
537 	case BITS_PARITY_SPACE:
538 		dbg("%s - parity = SPACE (not supported, disabling parity)",
539 				__func__);
540 		cflag &= ~PARENB;
541 		bits &= ~BITS_PARITY_MASK;
542 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
543 		break;
544 	default:
545 		dbg("%s - Unknown parity mode, disabling parity", __func__);
546 		cflag &= ~PARENB;
547 		bits &= ~BITS_PARITY_MASK;
548 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
549 		break;
550 	}
551 
552 	cflag &= ~CSTOPB;
553 	switch (bits & BITS_STOP_MASK) {
554 	case BITS_STOP_1:
555 		dbg("%s - stop bits = 1", __func__);
556 		break;
557 	case BITS_STOP_1_5:
558 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
559 								__func__);
560 		bits &= ~BITS_STOP_MASK;
561 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
562 		break;
563 	case BITS_STOP_2:
564 		dbg("%s - stop bits = 2", __func__);
565 		cflag |= CSTOPB;
566 		break;
567 	default:
568 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
569 								__func__);
570 		bits &= ~BITS_STOP_MASK;
571 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
572 		break;
573 	}
574 
575 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
576 	if (modem_ctl[0] & 0x0008) {
577 		dbg("%s - flow control = CRTSCTS", __func__);
578 		cflag |= CRTSCTS;
579 	} else {
580 		dbg("%s - flow control = NONE", __func__);
581 		cflag &= ~CRTSCTS;
582 	}
583 
584 	*cflagp = cflag;
585 }
586 
587 static void cp210x_set_termios(struct tty_struct *tty,
588 		struct usb_serial_port *port, struct ktermios *old_termios)
589 {
590 	unsigned int cflag, old_cflag;
591 	unsigned int baud = 0, bits;
592 	unsigned int modem_ctl[4];
593 
594 	dbg("%s - port %d", __func__, port->number);
595 
596 	if (!tty)
597 		return;
598 
599 	tty->termios->c_cflag &= ~CMSPAR;
600 	cflag = tty->termios->c_cflag;
601 	old_cflag = old_termios->c_cflag;
602 	baud = cp210x_quantise_baudrate(tty_get_baud_rate(tty));
603 
604 	/* If the baud rate is to be updated*/
605 	if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
606 		dbg("%s - Setting baud rate to %d baud", __func__,
607 				baud);
608 		if (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
609 					((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
610 			dbg("Baud rate requested not supported by device\n");
611 			baud = tty_termios_baud_rate(old_termios);
612 		}
613 	}
614 	/* Report back the resulting baud rate */
615 	tty_encode_baud_rate(tty, baud, baud);
616 
617 	/* If the number of data bits is to be updated */
618 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
619 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
620 		bits &= ~BITS_DATA_MASK;
621 		switch (cflag & CSIZE) {
622 		case CS5:
623 			bits |= BITS_DATA_5;
624 			dbg("%s - data bits = 5", __func__);
625 			break;
626 		case CS6:
627 			bits |= BITS_DATA_6;
628 			dbg("%s - data bits = 6", __func__);
629 			break;
630 		case CS7:
631 			bits |= BITS_DATA_7;
632 			dbg("%s - data bits = 7", __func__);
633 			break;
634 		case CS8:
635 			bits |= BITS_DATA_8;
636 			dbg("%s - data bits = 8", __func__);
637 			break;
638 		/*case CS9:
639 			bits |= BITS_DATA_9;
640 			dbg("%s - data bits = 9", __func__);
641 			break;*/
642 		default:
643 			dbg("cp210x driver does not "
644 					"support the number of bits requested,"
645 					" using 8 bit mode\n");
646 				bits |= BITS_DATA_8;
647 				break;
648 		}
649 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
650 			dbg("Number of data bits requested "
651 					"not supported by device\n");
652 	}
653 
654 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
655 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
656 		bits &= ~BITS_PARITY_MASK;
657 		if (cflag & PARENB) {
658 			if (cflag & PARODD) {
659 				bits |= BITS_PARITY_ODD;
660 				dbg("%s - parity = ODD", __func__);
661 			} else {
662 				bits |= BITS_PARITY_EVEN;
663 				dbg("%s - parity = EVEN", __func__);
664 			}
665 		}
666 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
667 			dbg("Parity mode not supported "
668 					"by device\n");
669 	}
670 
671 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
672 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
673 		bits &= ~BITS_STOP_MASK;
674 		if (cflag & CSTOPB) {
675 			bits |= BITS_STOP_2;
676 			dbg("%s - stop bits = 2", __func__);
677 		} else {
678 			bits |= BITS_STOP_1;
679 			dbg("%s - stop bits = 1", __func__);
680 		}
681 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
682 			dbg("Number of stop bits requested "
683 					"not supported by device\n");
684 	}
685 
686 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
687 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
688 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
689 				__func__, modem_ctl[0], modem_ctl[1],
690 				modem_ctl[2], modem_ctl[3]);
691 
692 		if (cflag & CRTSCTS) {
693 			modem_ctl[0] &= ~0x7B;
694 			modem_ctl[0] |= 0x09;
695 			modem_ctl[1] = 0x80;
696 			dbg("%s - flow control = CRTSCTS", __func__);
697 		} else {
698 			modem_ctl[0] &= ~0x7B;
699 			modem_ctl[0] |= 0x01;
700 			modem_ctl[1] |= 0x40;
701 			dbg("%s - flow control = NONE", __func__);
702 		}
703 
704 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
705 				__func__, modem_ctl[0], modem_ctl[1],
706 				modem_ctl[2], modem_ctl[3]);
707 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
708 	}
709 
710 }
711 
712 static int cp210x_tiocmset (struct tty_struct *tty, struct file *file,
713 		unsigned int set, unsigned int clear)
714 {
715 	struct usb_serial_port *port = tty->driver_data;
716 	return cp210x_tiocmset_port(port, file, set, clear);
717 }
718 
719 static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *file,
720 		unsigned int set, unsigned int clear)
721 {
722 	unsigned int control = 0;
723 
724 	dbg("%s - port %d", __func__, port->number);
725 
726 	if (set & TIOCM_RTS) {
727 		control |= CONTROL_RTS;
728 		control |= CONTROL_WRITE_RTS;
729 	}
730 	if (set & TIOCM_DTR) {
731 		control |= CONTROL_DTR;
732 		control |= CONTROL_WRITE_DTR;
733 	}
734 	if (clear & TIOCM_RTS) {
735 		control &= ~CONTROL_RTS;
736 		control |= CONTROL_WRITE_RTS;
737 	}
738 	if (clear & TIOCM_DTR) {
739 		control &= ~CONTROL_DTR;
740 		control |= CONTROL_WRITE_DTR;
741 	}
742 
743 	dbg("%s - control = 0x%.4x", __func__, control);
744 
745 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
746 }
747 
748 static int cp210x_tiocmget (struct tty_struct *tty, struct file *file)
749 {
750 	struct usb_serial_port *port = tty->driver_data;
751 	unsigned int control;
752 	int result;
753 
754 	dbg("%s - port %d", __func__, port->number);
755 
756 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
757 
758 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
759 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
760 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
761 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
762 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
763 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
764 
765 	dbg("%s - control = 0x%.2x", __func__, control);
766 
767 	return result;
768 }
769 
770 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
771 {
772 	struct usb_serial_port *port = tty->driver_data;
773 	unsigned int state;
774 
775 	dbg("%s - port %d", __func__, port->number);
776 	if (break_state == 0)
777 		state = BREAK_OFF;
778 	else
779 		state = BREAK_ON;
780 	dbg("%s - turning break %s", __func__,
781 			state == BREAK_OFF ? "off" : "on");
782 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
783 }
784 
785 static int cp210x_startup(struct usb_serial *serial)
786 {
787 	/* cp210x buffers behave strangely unless device is reset */
788 	usb_reset_device(serial->dev);
789 	return 0;
790 }
791 
792 static void cp210x_disconnect(struct usb_serial *serial)
793 {
794 	int i;
795 
796 	dbg("%s", __func__);
797 
798 	/* Stop reads and writes on all ports */
799 	for (i = 0; i < serial->num_ports; ++i)
800 		cp210x_cleanup(serial->port[i]);
801 }
802 
803 static int __init cp210x_init(void)
804 {
805 	int retval;
806 
807 	retval = usb_serial_register(&cp210x_device);
808 	if (retval)
809 		return retval; /* Failed to register */
810 
811 	retval = usb_register(&cp210x_driver);
812 	if (retval) {
813 		/* Failed to register */
814 		usb_serial_deregister(&cp210x_device);
815 		return retval;
816 	}
817 
818 	/* Success */
819 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
820 	       DRIVER_DESC "\n");
821 	return 0;
822 }
823 
824 static void __exit cp210x_exit(void)
825 {
826 	usb_deregister(&cp210x_driver);
827 	usb_serial_deregister(&cp210x_device);
828 }
829 
830 module_init(cp210x_init);
831 module_exit(cp210x_exit);
832 
833 MODULE_DESCRIPTION(DRIVER_DESC);
834 MODULE_VERSION(DRIVER_VERSION);
835 MODULE_LICENSE("GPL");
836 
837 module_param(debug, bool, S_IRUGO | S_IWUSR);
838 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
839