xref: /linux/drivers/usb/serial/cp210x.c (revision cdc32fd6f7b2b2580d7f1b74563f888e4dd9eb8a)
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_change_speed(struct tty_struct *, struct usb_serial_port *,
43 							struct ktermios *);
44 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
45 							struct ktermios*);
46 static int cp210x_tiocmget(struct tty_struct *);
47 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
48 static int cp210x_tiocmset_port(struct usb_serial_port *port,
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_dtr_rts(struct usb_serial_port *p, int on);
53 
54 static bool debug;
55 
56 static const struct usb_device_id id_table[] = {
57 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
58 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
59 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
60 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
61 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
62 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
63 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
64 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
65 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
66 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
67 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
68 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
69 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
70 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
71 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
72 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
73 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
74 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
75 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
76 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
77 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
78 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
79 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
80 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
81 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
82 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
83 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
84 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
85 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
86 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
87 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
88 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
89 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
90 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
91 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
92 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
93 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
94 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
95 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
96 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
97 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
98 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
99 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
100 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
101 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
102 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
103 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
104 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
105 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
106 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
107 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
108 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
109 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
110 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
111 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
112 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
113 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
114 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
115 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
116 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
117 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
118 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
119 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
120 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
121 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
122 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
123 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
124 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
125 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
126 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
127 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
128 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
129 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
130 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
131 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
132 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
133 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
134 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
135 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
136 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
137 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
138 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
139 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
140 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
141 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
142 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
143 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
144 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
145 	{ } /* Terminating Entry */
146 };
147 
148 MODULE_DEVICE_TABLE(usb, id_table);
149 
150 static struct usb_driver cp210x_driver = {
151 	.name		= "cp210x",
152 	.probe		= usb_serial_probe,
153 	.disconnect	= usb_serial_disconnect,
154 	.id_table	= id_table,
155 	.no_dynamic_id	= 	1,
156 };
157 
158 static struct usb_serial_driver cp210x_device = {
159 	.driver = {
160 		.owner =	THIS_MODULE,
161 		.name = 	"cp210x",
162 	},
163 	.usb_driver		= &cp210x_driver,
164 	.id_table		= id_table,
165 	.num_ports		= 1,
166 	.bulk_in_size		= 256,
167 	.bulk_out_size		= 256,
168 	.open			= cp210x_open,
169 	.close			= cp210x_close,
170 	.break_ctl		= cp210x_break_ctl,
171 	.set_termios		= cp210x_set_termios,
172 	.tiocmget 		= cp210x_tiocmget,
173 	.tiocmset		= cp210x_tiocmset,
174 	.attach			= cp210x_startup,
175 	.dtr_rts		= cp210x_dtr_rts
176 };
177 
178 /* Config request types */
179 #define REQTYPE_HOST_TO_DEVICE	0x41
180 #define REQTYPE_DEVICE_TO_HOST	0xc1
181 
182 /* Config request codes */
183 #define CP210X_IFC_ENABLE	0x00
184 #define CP210X_SET_BAUDDIV	0x01
185 #define CP210X_GET_BAUDDIV	0x02
186 #define CP210X_SET_LINE_CTL	0x03
187 #define CP210X_GET_LINE_CTL	0x04
188 #define CP210X_SET_BREAK	0x05
189 #define CP210X_IMM_CHAR		0x06
190 #define CP210X_SET_MHS		0x07
191 #define CP210X_GET_MDMSTS	0x08
192 #define CP210X_SET_XON		0x09
193 #define CP210X_SET_XOFF		0x0A
194 #define CP210X_SET_EVENTMASK	0x0B
195 #define CP210X_GET_EVENTMASK	0x0C
196 #define CP210X_SET_CHAR		0x0D
197 #define CP210X_GET_CHARS	0x0E
198 #define CP210X_GET_PROPS	0x0F
199 #define CP210X_GET_COMM_STATUS	0x10
200 #define CP210X_RESET		0x11
201 #define CP210X_PURGE		0x12
202 #define CP210X_SET_FLOW		0x13
203 #define CP210X_GET_FLOW		0x14
204 #define CP210X_EMBED_EVENTS	0x15
205 #define CP210X_GET_EVENTSTATE	0x16
206 #define CP210X_SET_CHARS	0x19
207 #define CP210X_GET_BAUDRATE	0x1D
208 #define CP210X_SET_BAUDRATE	0x1E
209 
210 /* CP210X_IFC_ENABLE */
211 #define UART_ENABLE		0x0001
212 #define UART_DISABLE		0x0000
213 
214 /* CP210X_(SET|GET)_BAUDDIV */
215 #define BAUD_RATE_GEN_FREQ	0x384000
216 
217 /* CP210X_(SET|GET)_LINE_CTL */
218 #define BITS_DATA_MASK		0X0f00
219 #define BITS_DATA_5		0X0500
220 #define BITS_DATA_6		0X0600
221 #define BITS_DATA_7		0X0700
222 #define BITS_DATA_8		0X0800
223 #define BITS_DATA_9		0X0900
224 
225 #define BITS_PARITY_MASK	0x00f0
226 #define BITS_PARITY_NONE	0x0000
227 #define BITS_PARITY_ODD		0x0010
228 #define BITS_PARITY_EVEN	0x0020
229 #define BITS_PARITY_MARK	0x0030
230 #define BITS_PARITY_SPACE	0x0040
231 
232 #define BITS_STOP_MASK		0x000f
233 #define BITS_STOP_1		0x0000
234 #define BITS_STOP_1_5		0x0001
235 #define BITS_STOP_2		0x0002
236 
237 /* CP210X_SET_BREAK */
238 #define BREAK_ON		0x0001
239 #define BREAK_OFF		0x0000
240 
241 /* CP210X_(SET_MHS|GET_MDMSTS) */
242 #define CONTROL_DTR		0x0001
243 #define CONTROL_RTS		0x0002
244 #define CONTROL_CTS		0x0010
245 #define CONTROL_DSR		0x0020
246 #define CONTROL_RING		0x0040
247 #define CONTROL_DCD		0x0080
248 #define CONTROL_WRITE_DTR	0x0100
249 #define CONTROL_WRITE_RTS	0x0200
250 
251 /*
252  * cp210x_get_config
253  * Reads from the CP210x configuration registers
254  * 'size' is specified in bytes.
255  * 'data' is a pointer to a pre-allocated array of integers large
256  * enough to hold 'size' bytes (with 4 bytes to each integer)
257  */
258 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
259 		unsigned int *data, int size)
260 {
261 	struct usb_serial *serial = port->serial;
262 	__le32 *buf;
263 	int result, i, length;
264 
265 	/* Number of integers required to contain the array */
266 	length = (((size - 1) | 3) + 1)/4;
267 
268 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
269 	if (!buf) {
270 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
271 		return -ENOMEM;
272 	}
273 
274 	/* Issue the request, attempting to read 'size' bytes */
275 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
276 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
277 				0, buf, size, 300);
278 
279 	/* Convert data into an array of integers */
280 	for (i = 0; i < length; i++)
281 		data[i] = le32_to_cpu(buf[i]);
282 
283 	kfree(buf);
284 
285 	if (result != size) {
286 		dbg("%s - Unable to send config request, "
287 				"request=0x%x size=%d result=%d\n",
288 				__func__, request, size, result);
289 		if (result > 0)
290 			result = -EPROTO;
291 
292 		return result;
293 	}
294 
295 	return 0;
296 }
297 
298 /*
299  * cp210x_set_config
300  * Writes to the CP210x configuration registers
301  * Values less than 16 bits wide are sent directly
302  * 'size' is specified in bytes.
303  */
304 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
305 		unsigned int *data, int size)
306 {
307 	struct usb_serial *serial = port->serial;
308 	__le32 *buf;
309 	int result, i, length;
310 
311 	/* Number of integers required to contain the array */
312 	length = (((size - 1) | 3) + 1)/4;
313 
314 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
315 	if (!buf) {
316 		dev_err(&port->dev, "%s - out of memory.\n",
317 				__func__);
318 		return -ENOMEM;
319 	}
320 
321 	/* Array of integers into bytes */
322 	for (i = 0; i < length; i++)
323 		buf[i] = cpu_to_le32(data[i]);
324 
325 	if (size > 2) {
326 		result = usb_control_msg(serial->dev,
327 				usb_sndctrlpipe(serial->dev, 0),
328 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
329 				0, buf, size, 300);
330 	} else {
331 		result = usb_control_msg(serial->dev,
332 				usb_sndctrlpipe(serial->dev, 0),
333 				request, REQTYPE_HOST_TO_DEVICE, data[0],
334 				0, NULL, 0, 300);
335 	}
336 
337 	kfree(buf);
338 
339 	if ((size > 2 && result != size) || result < 0) {
340 		dbg("%s - Unable to send request, "
341 				"request=0x%x size=%d result=%d\n",
342 				__func__, request, size, result);
343 		if (result > 0)
344 			result = -EPROTO;
345 
346 		return result;
347 	}
348 
349 	return 0;
350 }
351 
352 /*
353  * cp210x_set_config_single
354  * Convenience function for calling cp210x_set_config on single data values
355  * without requiring an integer pointer
356  */
357 static inline int cp210x_set_config_single(struct usb_serial_port *port,
358 		u8 request, unsigned int data)
359 {
360 	return cp210x_set_config(port, request, &data, 2);
361 }
362 
363 /*
364  * cp210x_quantise_baudrate
365  * Quantises the baud rate as per AN205 Table 1
366  */
367 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
368 	if (baud <= 300)
369 		baud = 300;
370 	else if (baud <= 600)      baud = 600;
371 	else if (baud <= 1200)     baud = 1200;
372 	else if (baud <= 1800)     baud = 1800;
373 	else if (baud <= 2400)     baud = 2400;
374 	else if (baud <= 4000)     baud = 4000;
375 	else if (baud <= 4803)     baud = 4800;
376 	else if (baud <= 7207)     baud = 7200;
377 	else if (baud <= 9612)     baud = 9600;
378 	else if (baud <= 14428)    baud = 14400;
379 	else if (baud <= 16062)    baud = 16000;
380 	else if (baud <= 19250)    baud = 19200;
381 	else if (baud <= 28912)    baud = 28800;
382 	else if (baud <= 38601)    baud = 38400;
383 	else if (baud <= 51558)    baud = 51200;
384 	else if (baud <= 56280)    baud = 56000;
385 	else if (baud <= 58053)    baud = 57600;
386 	else if (baud <= 64111)    baud = 64000;
387 	else if (baud <= 77608)    baud = 76800;
388 	else if (baud <= 117028)   baud = 115200;
389 	else if (baud <= 129347)   baud = 128000;
390 	else if (baud <= 156868)   baud = 153600;
391 	else if (baud <= 237832)   baud = 230400;
392 	else if (baud <= 254234)   baud = 250000;
393 	else if (baud <= 273066)   baud = 256000;
394 	else if (baud <= 491520)   baud = 460800;
395 	else if (baud <= 567138)   baud = 500000;
396 	else if (baud <= 670254)   baud = 576000;
397 	else if (baud <= 1053257)  baud = 921600;
398 	else if (baud <= 1474560)  baud = 1228800;
399 	else if (baud <= 2457600)  baud = 1843200;
400 	else                       baud = 3686400;
401 	return baud;
402 }
403 
404 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
405 {
406 	int result;
407 
408 	dbg("%s - port %d", __func__, port->number);
409 
410 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
411 								UART_ENABLE);
412 	if (result) {
413 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
414 		return result;
415 	}
416 
417 	/* Configure the termios structure */
418 	cp210x_get_termios(tty, port);
419 
420 	/* The baud rate must be initialised on cp2104 */
421 	if (tty)
422 		cp210x_change_speed(tty, port, NULL);
423 
424 	return usb_serial_generic_open(tty, port);
425 }
426 
427 static void cp210x_close(struct usb_serial_port *port)
428 {
429 	dbg("%s - port %d", __func__, port->number);
430 
431 	usb_serial_generic_close(port);
432 
433 	mutex_lock(&port->serial->disc_mutex);
434 	if (!port->serial->disconnected)
435 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
436 	mutex_unlock(&port->serial->disc_mutex);
437 }
438 
439 /*
440  * cp210x_get_termios
441  * Reads the baud rate, data bits, parity, stop bits and flow control mode
442  * from the device, corrects any unsupported values, and configures the
443  * termios structure to reflect the state of the device
444  */
445 static void cp210x_get_termios(struct tty_struct *tty,
446 	struct usb_serial_port *port)
447 {
448 	unsigned int baud;
449 
450 	if (tty) {
451 		cp210x_get_termios_port(tty->driver_data,
452 			&tty->termios->c_cflag, &baud);
453 		tty_encode_baud_rate(tty, baud, baud);
454 	}
455 
456 	else {
457 		unsigned int cflag;
458 		cflag = 0;
459 		cp210x_get_termios_port(port, &cflag, &baud);
460 	}
461 }
462 
463 /*
464  * cp210x_get_termios_port
465  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
466  */
467 static void cp210x_get_termios_port(struct usb_serial_port *port,
468 	unsigned int *cflagp, unsigned int *baudp)
469 {
470 	unsigned int cflag, modem_ctl[4];
471 	unsigned int baud;
472 	unsigned int bits;
473 
474 	dbg("%s - port %d", __func__, port->number);
475 
476 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
477 
478 	dbg("%s - baud rate = %d", __func__, baud);
479 	*baudp = baud;
480 
481 	cflag = *cflagp;
482 
483 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
484 	cflag &= ~CSIZE;
485 	switch (bits & BITS_DATA_MASK) {
486 	case BITS_DATA_5:
487 		dbg("%s - data bits = 5", __func__);
488 		cflag |= CS5;
489 		break;
490 	case BITS_DATA_6:
491 		dbg("%s - data bits = 6", __func__);
492 		cflag |= CS6;
493 		break;
494 	case BITS_DATA_7:
495 		dbg("%s - data bits = 7", __func__);
496 		cflag |= CS7;
497 		break;
498 	case BITS_DATA_8:
499 		dbg("%s - data bits = 8", __func__);
500 		cflag |= CS8;
501 		break;
502 	case BITS_DATA_9:
503 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
504 								__func__);
505 		cflag |= CS8;
506 		bits &= ~BITS_DATA_MASK;
507 		bits |= BITS_DATA_8;
508 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
509 		break;
510 	default:
511 		dbg("%s - Unknown number of data bits, using 8", __func__);
512 		cflag |= CS8;
513 		bits &= ~BITS_DATA_MASK;
514 		bits |= BITS_DATA_8;
515 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
516 		break;
517 	}
518 
519 	switch (bits & BITS_PARITY_MASK) {
520 	case BITS_PARITY_NONE:
521 		dbg("%s - parity = NONE", __func__);
522 		cflag &= ~PARENB;
523 		break;
524 	case BITS_PARITY_ODD:
525 		dbg("%s - parity = ODD", __func__);
526 		cflag |= (PARENB|PARODD);
527 		break;
528 	case BITS_PARITY_EVEN:
529 		dbg("%s - parity = EVEN", __func__);
530 		cflag &= ~PARODD;
531 		cflag |= PARENB;
532 		break;
533 	case BITS_PARITY_MARK:
534 		dbg("%s - parity = MARK", __func__);
535 		cflag |= (PARENB|PARODD|CMSPAR);
536 		break;
537 	case BITS_PARITY_SPACE:
538 		dbg("%s - parity = SPACE", __func__);
539 		cflag &= ~PARODD;
540 		cflag |= (PARENB|CMSPAR);
541 		break;
542 	default:
543 		dbg("%s - Unknown parity mode, disabling parity", __func__);
544 		cflag &= ~PARENB;
545 		bits &= ~BITS_PARITY_MASK;
546 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
547 		break;
548 	}
549 
550 	cflag &= ~CSTOPB;
551 	switch (bits & BITS_STOP_MASK) {
552 	case BITS_STOP_1:
553 		dbg("%s - stop bits = 1", __func__);
554 		break;
555 	case BITS_STOP_1_5:
556 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
557 								__func__);
558 		bits &= ~BITS_STOP_MASK;
559 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
560 		break;
561 	case BITS_STOP_2:
562 		dbg("%s - stop bits = 2", __func__);
563 		cflag |= CSTOPB;
564 		break;
565 	default:
566 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
567 								__func__);
568 		bits &= ~BITS_STOP_MASK;
569 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
570 		break;
571 	}
572 
573 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
574 	if (modem_ctl[0] & 0x0008) {
575 		dbg("%s - flow control = CRTSCTS", __func__);
576 		cflag |= CRTSCTS;
577 	} else {
578 		dbg("%s - flow control = NONE", __func__);
579 		cflag &= ~CRTSCTS;
580 	}
581 
582 	*cflagp = cflag;
583 }
584 
585 /*
586  * CP2101 supports the following baud rates:
587  *
588  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
589  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
590  *
591  * CP2102 and CP2103 support the following additional rates:
592  *
593  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
594  *	576000
595  *
596  * The device will map a requested rate to a supported one, but the result
597  * of requests for rates greater than 1053257 is undefined (see AN205).
598  *
599  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
600  * respectively, with an error less than 1%. The actual rates are determined
601  * by
602  *
603  *	div = round(freq / (2 x prescale x request))
604  *	actual = freq / (2 x prescale x div)
605  *
606  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
607  * or 1 otherwise.
608  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
609  * otherwise.
610  */
611 static void cp210x_change_speed(struct tty_struct *tty,
612 		struct usb_serial_port *port, struct ktermios *old_termios)
613 {
614 	u32 baud;
615 
616 	baud = tty->termios->c_ospeed;
617 
618 	/* This maps the requested rate to a rate valid on cp2102 or cp2103.
619 	 *
620 	 * NOTE: B0 is not implemented.
621 	 */
622 	baud = cp210x_quantise_baudrate(baud);
623 
624 	dbg("%s - setting baud rate to %u", __func__, baud);
625 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
626 							sizeof(baud))) {
627 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
628 		if (old_termios)
629 			baud = old_termios->c_ospeed;
630 		else
631 			baud = 9600;
632 	}
633 
634 	tty_encode_baud_rate(tty, baud, baud);
635 }
636 
637 static void cp210x_set_termios(struct tty_struct *tty,
638 		struct usb_serial_port *port, struct ktermios *old_termios)
639 {
640 	unsigned int cflag, old_cflag;
641 	unsigned int bits;
642 	unsigned int modem_ctl[4];
643 
644 	dbg("%s - port %d", __func__, port->number);
645 
646 	if (!tty)
647 		return;
648 
649 	cflag = tty->termios->c_cflag;
650 	old_cflag = old_termios->c_cflag;
651 
652 	if (tty->termios->c_ospeed != old_termios->c_ospeed)
653 		cp210x_change_speed(tty, port, old_termios);
654 
655 	/* If the number of data bits is to be updated */
656 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
657 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
658 		bits &= ~BITS_DATA_MASK;
659 		switch (cflag & CSIZE) {
660 		case CS5:
661 			bits |= BITS_DATA_5;
662 			dbg("%s - data bits = 5", __func__);
663 			break;
664 		case CS6:
665 			bits |= BITS_DATA_6;
666 			dbg("%s - data bits = 6", __func__);
667 			break;
668 		case CS7:
669 			bits |= BITS_DATA_7;
670 			dbg("%s - data bits = 7", __func__);
671 			break;
672 		case CS8:
673 			bits |= BITS_DATA_8;
674 			dbg("%s - data bits = 8", __func__);
675 			break;
676 		/*case CS9:
677 			bits |= BITS_DATA_9;
678 			dbg("%s - data bits = 9", __func__);
679 			break;*/
680 		default:
681 			dbg("cp210x driver does not "
682 					"support the number of bits requested,"
683 					" using 8 bit mode\n");
684 				bits |= BITS_DATA_8;
685 				break;
686 		}
687 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
688 			dbg("Number of data bits requested "
689 					"not supported by device\n");
690 	}
691 
692 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
693 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
694 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
695 		bits &= ~BITS_PARITY_MASK;
696 		if (cflag & PARENB) {
697 			if (cflag & CMSPAR) {
698 			    if (cflag & PARODD) {
699 				    bits |= BITS_PARITY_MARK;
700 				    dbg("%s - parity = MARK", __func__);
701 			    } else {
702 				    bits |= BITS_PARITY_SPACE;
703 				    dbg("%s - parity = SPACE", __func__);
704 			    }
705 			} else {
706 			    if (cflag & PARODD) {
707 				    bits |= BITS_PARITY_ODD;
708 				    dbg("%s - parity = ODD", __func__);
709 			    } else {
710 				    bits |= BITS_PARITY_EVEN;
711 				    dbg("%s - parity = EVEN", __func__);
712 			    }
713 			}
714 		}
715 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
716 			dbg("Parity mode not supported "
717 					"by device\n");
718 	}
719 
720 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
721 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
722 		bits &= ~BITS_STOP_MASK;
723 		if (cflag & CSTOPB) {
724 			bits |= BITS_STOP_2;
725 			dbg("%s - stop bits = 2", __func__);
726 		} else {
727 			bits |= BITS_STOP_1;
728 			dbg("%s - stop bits = 1", __func__);
729 		}
730 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
731 			dbg("Number of stop bits requested "
732 					"not supported by device\n");
733 	}
734 
735 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
736 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
737 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
738 				__func__, modem_ctl[0], modem_ctl[1],
739 				modem_ctl[2], modem_ctl[3]);
740 
741 		if (cflag & CRTSCTS) {
742 			modem_ctl[0] &= ~0x7B;
743 			modem_ctl[0] |= 0x09;
744 			modem_ctl[1] = 0x80;
745 			dbg("%s - flow control = CRTSCTS", __func__);
746 		} else {
747 			modem_ctl[0] &= ~0x7B;
748 			modem_ctl[0] |= 0x01;
749 			modem_ctl[1] |= 0x40;
750 			dbg("%s - flow control = NONE", __func__);
751 		}
752 
753 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
754 				__func__, modem_ctl[0], modem_ctl[1],
755 				modem_ctl[2], modem_ctl[3]);
756 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
757 	}
758 
759 }
760 
761 static int cp210x_tiocmset (struct tty_struct *tty,
762 		unsigned int set, unsigned int clear)
763 {
764 	struct usb_serial_port *port = tty->driver_data;
765 	return cp210x_tiocmset_port(port, set, clear);
766 }
767 
768 static int cp210x_tiocmset_port(struct usb_serial_port *port,
769 		unsigned int set, unsigned int clear)
770 {
771 	unsigned int control = 0;
772 
773 	dbg("%s - port %d", __func__, port->number);
774 
775 	if (set & TIOCM_RTS) {
776 		control |= CONTROL_RTS;
777 		control |= CONTROL_WRITE_RTS;
778 	}
779 	if (set & TIOCM_DTR) {
780 		control |= CONTROL_DTR;
781 		control |= CONTROL_WRITE_DTR;
782 	}
783 	if (clear & TIOCM_RTS) {
784 		control &= ~CONTROL_RTS;
785 		control |= CONTROL_WRITE_RTS;
786 	}
787 	if (clear & TIOCM_DTR) {
788 		control &= ~CONTROL_DTR;
789 		control |= CONTROL_WRITE_DTR;
790 	}
791 
792 	dbg("%s - control = 0x%.4x", __func__, control);
793 
794 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
795 }
796 
797 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
798 {
799 	if (on)
800 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
801 	else
802 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
803 }
804 
805 static int cp210x_tiocmget (struct tty_struct *tty)
806 {
807 	struct usb_serial_port *port = tty->driver_data;
808 	unsigned int control;
809 	int result;
810 
811 	dbg("%s - port %d", __func__, port->number);
812 
813 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
814 
815 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
816 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
817 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
818 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
819 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
820 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
821 
822 	dbg("%s - control = 0x%.2x", __func__, control);
823 
824 	return result;
825 }
826 
827 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
828 {
829 	struct usb_serial_port *port = tty->driver_data;
830 	unsigned int state;
831 
832 	dbg("%s - port %d", __func__, port->number);
833 	if (break_state == 0)
834 		state = BREAK_OFF;
835 	else
836 		state = BREAK_ON;
837 	dbg("%s - turning break %s", __func__,
838 			state == BREAK_OFF ? "off" : "on");
839 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
840 }
841 
842 static int cp210x_startup(struct usb_serial *serial)
843 {
844 	/* cp210x buffers behave strangely unless device is reset */
845 	usb_reset_device(serial->dev);
846 	return 0;
847 }
848 
849 static int __init cp210x_init(void)
850 {
851 	int retval;
852 
853 	retval = usb_serial_register(&cp210x_device);
854 	if (retval)
855 		return retval; /* Failed to register */
856 
857 	retval = usb_register(&cp210x_driver);
858 	if (retval) {
859 		/* Failed to register */
860 		usb_serial_deregister(&cp210x_device);
861 		return retval;
862 	}
863 
864 	/* Success */
865 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
866 	       DRIVER_DESC "\n");
867 	return 0;
868 }
869 
870 static void __exit cp210x_exit(void)
871 {
872 	usb_deregister(&cp210x_driver);
873 	usb_serial_deregister(&cp210x_device);
874 }
875 
876 module_init(cp210x_init);
877 module_exit(cp210x_exit);
878 
879 MODULE_DESCRIPTION(DRIVER_DESC);
880 MODULE_VERSION(DRIVER_VERSION);
881 MODULE_LICENSE("GPL");
882 
883 module_param(debug, bool, S_IRUGO | S_IWUSR);
884 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
885