xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision e5990874e511d5bbca23b3396419480cb2ca0ee7)
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 	return usb_serial_generic_open(tty, port);
421 }
422 
423 static void cp210x_close(struct usb_serial_port *port)
424 {
425 	dbg("%s - port %d", __func__, port->number);
426 
427 	usb_serial_generic_close(port);
428 
429 	mutex_lock(&port->serial->disc_mutex);
430 	if (!port->serial->disconnected)
431 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
432 	mutex_unlock(&port->serial->disc_mutex);
433 }
434 
435 /*
436  * cp210x_get_termios
437  * Reads the baud rate, data bits, parity, stop bits and flow control mode
438  * from the device, corrects any unsupported values, and configures the
439  * termios structure to reflect the state of the device
440  */
441 static void cp210x_get_termios(struct tty_struct *tty,
442 	struct usb_serial_port *port)
443 {
444 	unsigned int baud;
445 
446 	if (tty) {
447 		cp210x_get_termios_port(tty->driver_data,
448 			&tty->termios->c_cflag, &baud);
449 		tty_encode_baud_rate(tty, baud, baud);
450 	}
451 
452 	else {
453 		unsigned int cflag;
454 		cflag = 0;
455 		cp210x_get_termios_port(port, &cflag, &baud);
456 	}
457 }
458 
459 /*
460  * cp210x_get_termios_port
461  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
462  */
463 static void cp210x_get_termios_port(struct usb_serial_port *port,
464 	unsigned int *cflagp, unsigned int *baudp)
465 {
466 	unsigned int cflag, modem_ctl[4];
467 	unsigned int baud;
468 	unsigned int bits;
469 
470 	dbg("%s - port %d", __func__, port->number);
471 
472 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
473 
474 	dbg("%s - baud rate = %d", __func__, baud);
475 	*baudp = baud;
476 
477 	cflag = *cflagp;
478 
479 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
480 	cflag &= ~CSIZE;
481 	switch (bits & BITS_DATA_MASK) {
482 	case BITS_DATA_5:
483 		dbg("%s - data bits = 5", __func__);
484 		cflag |= CS5;
485 		break;
486 	case BITS_DATA_6:
487 		dbg("%s - data bits = 6", __func__);
488 		cflag |= CS6;
489 		break;
490 	case BITS_DATA_7:
491 		dbg("%s - data bits = 7", __func__);
492 		cflag |= CS7;
493 		break;
494 	case BITS_DATA_8:
495 		dbg("%s - data bits = 8", __func__);
496 		cflag |= CS8;
497 		break;
498 	case BITS_DATA_9:
499 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
500 								__func__);
501 		cflag |= CS8;
502 		bits &= ~BITS_DATA_MASK;
503 		bits |= BITS_DATA_8;
504 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
505 		break;
506 	default:
507 		dbg("%s - Unknown number of data bits, using 8", __func__);
508 		cflag |= CS8;
509 		bits &= ~BITS_DATA_MASK;
510 		bits |= BITS_DATA_8;
511 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
512 		break;
513 	}
514 
515 	switch (bits & BITS_PARITY_MASK) {
516 	case BITS_PARITY_NONE:
517 		dbg("%s - parity = NONE", __func__);
518 		cflag &= ~PARENB;
519 		break;
520 	case BITS_PARITY_ODD:
521 		dbg("%s - parity = ODD", __func__);
522 		cflag |= (PARENB|PARODD);
523 		break;
524 	case BITS_PARITY_EVEN:
525 		dbg("%s - parity = EVEN", __func__);
526 		cflag &= ~PARODD;
527 		cflag |= PARENB;
528 		break;
529 	case BITS_PARITY_MARK:
530 		dbg("%s - parity = MARK", __func__);
531 		cflag |= (PARENB|PARODD|CMSPAR);
532 		break;
533 	case BITS_PARITY_SPACE:
534 		dbg("%s - parity = SPACE", __func__);
535 		cflag &= ~PARODD;
536 		cflag |= (PARENB|CMSPAR);
537 		break;
538 	default:
539 		dbg("%s - Unknown parity mode, disabling parity", __func__);
540 		cflag &= ~PARENB;
541 		bits &= ~BITS_PARITY_MASK;
542 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
543 		break;
544 	}
545 
546 	cflag &= ~CSTOPB;
547 	switch (bits & BITS_STOP_MASK) {
548 	case BITS_STOP_1:
549 		dbg("%s - stop bits = 1", __func__);
550 		break;
551 	case BITS_STOP_1_5:
552 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
553 								__func__);
554 		bits &= ~BITS_STOP_MASK;
555 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
556 		break;
557 	case BITS_STOP_2:
558 		dbg("%s - stop bits = 2", __func__);
559 		cflag |= CSTOPB;
560 		break;
561 	default:
562 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
563 								__func__);
564 		bits &= ~BITS_STOP_MASK;
565 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
566 		break;
567 	}
568 
569 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
570 	if (modem_ctl[0] & 0x0008) {
571 		dbg("%s - flow control = CRTSCTS", __func__);
572 		cflag |= CRTSCTS;
573 	} else {
574 		dbg("%s - flow control = NONE", __func__);
575 		cflag &= ~CRTSCTS;
576 	}
577 
578 	*cflagp = cflag;
579 }
580 
581 /*
582  * CP2101 supports the following baud rates:
583  *
584  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
585  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
586  *
587  * CP2102 and CP2103 support the following additional rates:
588  *
589  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
590  *	576000
591  *
592  * The device will map a requested rate to a supported one, but the result
593  * of requests for rates greater than 1053257 is undefined (see AN205).
594  *
595  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
596  * respectively, with an error less than 1%. The actual rates are determined
597  * by
598  *
599  *	div = round(freq / (2 x prescale x request))
600  *	actual = freq / (2 x prescale x div)
601  *
602  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
603  * or 1 otherwise.
604  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
605  * otherwise.
606  */
607 static void cp210x_change_speed(struct tty_struct *tty,
608 		struct usb_serial_port *port, struct ktermios *old_termios)
609 {
610 	u32 baud;
611 
612 	baud = tty->termios->c_ospeed;
613 
614 	/* This maps the requested rate to a rate valid on cp2102 or cp2103.
615 	 *
616 	 * NOTE: B0 is not implemented.
617 	 */
618 	baud = cp210x_quantise_baudrate(baud);
619 
620 	dbg("%s - setting baud rate to %u", __func__, baud);
621 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
622 							sizeof(baud))) {
623 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
624 		if (old_termios)
625 			baud = old_termios->c_ospeed;
626 		else
627 			baud = 9600;
628 	}
629 
630 	tty_encode_baud_rate(tty, baud, baud);
631 }
632 
633 static void cp210x_set_termios(struct tty_struct *tty,
634 		struct usb_serial_port *port, struct ktermios *old_termios)
635 {
636 	unsigned int cflag, old_cflag;
637 	unsigned int bits;
638 	unsigned int modem_ctl[4];
639 
640 	dbg("%s - port %d", __func__, port->number);
641 
642 	if (!tty)
643 		return;
644 
645 	cflag = tty->termios->c_cflag;
646 	old_cflag = old_termios->c_cflag;
647 
648 	if (tty->termios->c_ospeed != old_termios->c_ospeed)
649 		cp210x_change_speed(tty, port, old_termios);
650 
651 	/* If the number of data bits is to be updated */
652 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
653 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
654 		bits &= ~BITS_DATA_MASK;
655 		switch (cflag & CSIZE) {
656 		case CS5:
657 			bits |= BITS_DATA_5;
658 			dbg("%s - data bits = 5", __func__);
659 			break;
660 		case CS6:
661 			bits |= BITS_DATA_6;
662 			dbg("%s - data bits = 6", __func__);
663 			break;
664 		case CS7:
665 			bits |= BITS_DATA_7;
666 			dbg("%s - data bits = 7", __func__);
667 			break;
668 		case CS8:
669 			bits |= BITS_DATA_8;
670 			dbg("%s - data bits = 8", __func__);
671 			break;
672 		/*case CS9:
673 			bits |= BITS_DATA_9;
674 			dbg("%s - data bits = 9", __func__);
675 			break;*/
676 		default:
677 			dbg("cp210x driver does not "
678 					"support the number of bits requested,"
679 					" using 8 bit mode\n");
680 				bits |= BITS_DATA_8;
681 				break;
682 		}
683 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
684 			dbg("Number of data bits requested "
685 					"not supported by device\n");
686 	}
687 
688 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
689 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
690 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
691 		bits &= ~BITS_PARITY_MASK;
692 		if (cflag & PARENB) {
693 			if (cflag & CMSPAR) {
694 			    if (cflag & PARODD) {
695 				    bits |= BITS_PARITY_MARK;
696 				    dbg("%s - parity = MARK", __func__);
697 			    } else {
698 				    bits |= BITS_PARITY_SPACE;
699 				    dbg("%s - parity = SPACE", __func__);
700 			    }
701 			} else {
702 			    if (cflag & PARODD) {
703 				    bits |= BITS_PARITY_ODD;
704 				    dbg("%s - parity = ODD", __func__);
705 			    } else {
706 				    bits |= BITS_PARITY_EVEN;
707 				    dbg("%s - parity = EVEN", __func__);
708 			    }
709 			}
710 		}
711 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
712 			dbg("Parity mode not supported "
713 					"by device\n");
714 	}
715 
716 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
717 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
718 		bits &= ~BITS_STOP_MASK;
719 		if (cflag & CSTOPB) {
720 			bits |= BITS_STOP_2;
721 			dbg("%s - stop bits = 2", __func__);
722 		} else {
723 			bits |= BITS_STOP_1;
724 			dbg("%s - stop bits = 1", __func__);
725 		}
726 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
727 			dbg("Number of stop bits requested "
728 					"not supported by device\n");
729 	}
730 
731 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
732 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
733 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
734 				__func__, modem_ctl[0], modem_ctl[1],
735 				modem_ctl[2], modem_ctl[3]);
736 
737 		if (cflag & CRTSCTS) {
738 			modem_ctl[0] &= ~0x7B;
739 			modem_ctl[0] |= 0x09;
740 			modem_ctl[1] = 0x80;
741 			dbg("%s - flow control = CRTSCTS", __func__);
742 		} else {
743 			modem_ctl[0] &= ~0x7B;
744 			modem_ctl[0] |= 0x01;
745 			modem_ctl[1] |= 0x40;
746 			dbg("%s - flow control = NONE", __func__);
747 		}
748 
749 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
750 				__func__, modem_ctl[0], modem_ctl[1],
751 				modem_ctl[2], modem_ctl[3]);
752 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
753 	}
754 
755 }
756 
757 static int cp210x_tiocmset (struct tty_struct *tty,
758 		unsigned int set, unsigned int clear)
759 {
760 	struct usb_serial_port *port = tty->driver_data;
761 	return cp210x_tiocmset_port(port, set, clear);
762 }
763 
764 static int cp210x_tiocmset_port(struct usb_serial_port *port,
765 		unsigned int set, unsigned int clear)
766 {
767 	unsigned int control = 0;
768 
769 	dbg("%s - port %d", __func__, port->number);
770 
771 	if (set & TIOCM_RTS) {
772 		control |= CONTROL_RTS;
773 		control |= CONTROL_WRITE_RTS;
774 	}
775 	if (set & TIOCM_DTR) {
776 		control |= CONTROL_DTR;
777 		control |= CONTROL_WRITE_DTR;
778 	}
779 	if (clear & TIOCM_RTS) {
780 		control &= ~CONTROL_RTS;
781 		control |= CONTROL_WRITE_RTS;
782 	}
783 	if (clear & TIOCM_DTR) {
784 		control &= ~CONTROL_DTR;
785 		control |= CONTROL_WRITE_DTR;
786 	}
787 
788 	dbg("%s - control = 0x%.4x", __func__, control);
789 
790 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
791 }
792 
793 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
794 {
795 	if (on)
796 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
797 	else
798 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
799 }
800 
801 static int cp210x_tiocmget (struct tty_struct *tty)
802 {
803 	struct usb_serial_port *port = tty->driver_data;
804 	unsigned int control;
805 	int result;
806 
807 	dbg("%s - port %d", __func__, port->number);
808 
809 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
810 
811 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
812 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
813 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
814 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
815 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
816 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
817 
818 	dbg("%s - control = 0x%.2x", __func__, control);
819 
820 	return result;
821 }
822 
823 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
824 {
825 	struct usb_serial_port *port = tty->driver_data;
826 	unsigned int state;
827 
828 	dbg("%s - port %d", __func__, port->number);
829 	if (break_state == 0)
830 		state = BREAK_OFF;
831 	else
832 		state = BREAK_ON;
833 	dbg("%s - turning break %s", __func__,
834 			state == BREAK_OFF ? "off" : "on");
835 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
836 }
837 
838 static int cp210x_startup(struct usb_serial *serial)
839 {
840 	/* cp210x buffers behave strangely unless device is reset */
841 	usb_reset_device(serial->dev);
842 	return 0;
843 }
844 
845 static int __init cp210x_init(void)
846 {
847 	int retval;
848 
849 	retval = usb_serial_register(&cp210x_device);
850 	if (retval)
851 		return retval; /* Failed to register */
852 
853 	retval = usb_register(&cp210x_driver);
854 	if (retval) {
855 		/* Failed to register */
856 		usb_serial_deregister(&cp210x_device);
857 		return retval;
858 	}
859 
860 	/* Success */
861 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
862 	       DRIVER_DESC "\n");
863 	return 0;
864 }
865 
866 static void __exit cp210x_exit(void)
867 {
868 	usb_deregister(&cp210x_driver);
869 	usb_serial_deregister(&cp210x_device);
870 }
871 
872 module_init(cp210x_init);
873 module_exit(cp210x_exit);
874 
875 MODULE_DESCRIPTION(DRIVER_DESC);
876 MODULE_VERSION(DRIVER_VERSION);
877 MODULE_LICENSE("GPL");
878 
879 module_param(debug, bool, S_IRUGO | S_IWUSR);
880 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
881