xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 63dc02bd)
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_release(struct usb_serial *);
53 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
54 
55 static bool debug;
56 
57 static const struct usb_device_id id_table[] = {
58 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
59 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
60 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
61 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
62 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
63 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
64 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
65 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
66 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
67 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
68 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
69 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
71 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
72 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
73 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
74 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
75 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
76 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
77 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
78 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
79 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
80 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
81 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
82 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
83 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
84 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
85 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
86 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
87 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
88 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
89 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
90 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
91 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
92 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
93 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
94 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
95 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
96 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
97 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
98 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
99 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
100 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
101 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
102 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
103 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
104 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
105 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
106 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
107 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
108 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
109 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
110 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
111 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
112 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
113 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
114 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
115 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
116 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
117 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
118 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
119 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
120 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
121 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
122 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
123 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
124 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
125 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
126 	{ USB_DEVICE(0x10C4, 0xEA80) }, /* Silicon Labs factory default */
127 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
128 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
129 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
130 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
131 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
132 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
133 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
134 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
135 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
136 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
137 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
138 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
139 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
140 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
141 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
142 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
143 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
144 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
145 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
146 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
147 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
148 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
149 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
150 	{ } /* Terminating Entry */
151 };
152 
153 MODULE_DEVICE_TABLE(usb, id_table);
154 
155 struct cp210x_port_private {
156 	__u8			bInterfaceNumber;
157 };
158 
159 static struct usb_driver cp210x_driver = {
160 	.name		= "cp210x",
161 	.probe		= usb_serial_probe,
162 	.disconnect	= usb_serial_disconnect,
163 	.id_table	= id_table,
164 };
165 
166 static struct usb_serial_driver cp210x_device = {
167 	.driver = {
168 		.owner =	THIS_MODULE,
169 		.name = 	"cp210x",
170 	},
171 	.id_table		= id_table,
172 	.num_ports		= 1,
173 	.bulk_in_size		= 256,
174 	.bulk_out_size		= 256,
175 	.open			= cp210x_open,
176 	.close			= cp210x_close,
177 	.break_ctl		= cp210x_break_ctl,
178 	.set_termios		= cp210x_set_termios,
179 	.tiocmget 		= cp210x_tiocmget,
180 	.tiocmset		= cp210x_tiocmset,
181 	.attach			= cp210x_startup,
182 	.release		= cp210x_release,
183 	.dtr_rts		= cp210x_dtr_rts
184 };
185 
186 static struct usb_serial_driver * const serial_drivers[] = {
187 	&cp210x_device, NULL
188 };
189 
190 /* Config request types */
191 #define REQTYPE_HOST_TO_DEVICE	0x41
192 #define REQTYPE_DEVICE_TO_HOST	0xc1
193 
194 /* Config request codes */
195 #define CP210X_IFC_ENABLE	0x00
196 #define CP210X_SET_BAUDDIV	0x01
197 #define CP210X_GET_BAUDDIV	0x02
198 #define CP210X_SET_LINE_CTL	0x03
199 #define CP210X_GET_LINE_CTL	0x04
200 #define CP210X_SET_BREAK	0x05
201 #define CP210X_IMM_CHAR		0x06
202 #define CP210X_SET_MHS		0x07
203 #define CP210X_GET_MDMSTS	0x08
204 #define CP210X_SET_XON		0x09
205 #define CP210X_SET_XOFF		0x0A
206 #define CP210X_SET_EVENTMASK	0x0B
207 #define CP210X_GET_EVENTMASK	0x0C
208 #define CP210X_SET_CHAR		0x0D
209 #define CP210X_GET_CHARS	0x0E
210 #define CP210X_GET_PROPS	0x0F
211 #define CP210X_GET_COMM_STATUS	0x10
212 #define CP210X_RESET		0x11
213 #define CP210X_PURGE		0x12
214 #define CP210X_SET_FLOW		0x13
215 #define CP210X_GET_FLOW		0x14
216 #define CP210X_EMBED_EVENTS	0x15
217 #define CP210X_GET_EVENTSTATE	0x16
218 #define CP210X_SET_CHARS	0x19
219 #define CP210X_GET_BAUDRATE	0x1D
220 #define CP210X_SET_BAUDRATE	0x1E
221 
222 /* CP210X_IFC_ENABLE */
223 #define UART_ENABLE		0x0001
224 #define UART_DISABLE		0x0000
225 
226 /* CP210X_(SET|GET)_BAUDDIV */
227 #define BAUD_RATE_GEN_FREQ	0x384000
228 
229 /* CP210X_(SET|GET)_LINE_CTL */
230 #define BITS_DATA_MASK		0X0f00
231 #define BITS_DATA_5		0X0500
232 #define BITS_DATA_6		0X0600
233 #define BITS_DATA_7		0X0700
234 #define BITS_DATA_8		0X0800
235 #define BITS_DATA_9		0X0900
236 
237 #define BITS_PARITY_MASK	0x00f0
238 #define BITS_PARITY_NONE	0x0000
239 #define BITS_PARITY_ODD		0x0010
240 #define BITS_PARITY_EVEN	0x0020
241 #define BITS_PARITY_MARK	0x0030
242 #define BITS_PARITY_SPACE	0x0040
243 
244 #define BITS_STOP_MASK		0x000f
245 #define BITS_STOP_1		0x0000
246 #define BITS_STOP_1_5		0x0001
247 #define BITS_STOP_2		0x0002
248 
249 /* CP210X_SET_BREAK */
250 #define BREAK_ON		0x0001
251 #define BREAK_OFF		0x0000
252 
253 /* CP210X_(SET_MHS|GET_MDMSTS) */
254 #define CONTROL_DTR		0x0001
255 #define CONTROL_RTS		0x0002
256 #define CONTROL_CTS		0x0010
257 #define CONTROL_DSR		0x0020
258 #define CONTROL_RING		0x0040
259 #define CONTROL_DCD		0x0080
260 #define CONTROL_WRITE_DTR	0x0100
261 #define CONTROL_WRITE_RTS	0x0200
262 
263 /*
264  * cp210x_get_config
265  * Reads from the CP210x configuration registers
266  * 'size' is specified in bytes.
267  * 'data' is a pointer to a pre-allocated array of integers large
268  * enough to hold 'size' bytes (with 4 bytes to each integer)
269  */
270 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
271 		unsigned int *data, int size)
272 {
273 	struct usb_serial *serial = port->serial;
274 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
275 	__le32 *buf;
276 	int result, i, length;
277 
278 	/* Number of integers required to contain the array */
279 	length = (((size - 1) | 3) + 1)/4;
280 
281 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
282 	if (!buf) {
283 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
284 		return -ENOMEM;
285 	}
286 
287 	/* Issue the request, attempting to read 'size' bytes */
288 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
289 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
290 				port_priv->bInterfaceNumber, buf, size,
291 				USB_CTRL_GET_TIMEOUT);
292 
293 	/* Convert data into an array of integers */
294 	for (i = 0; i < length; i++)
295 		data[i] = le32_to_cpu(buf[i]);
296 
297 	kfree(buf);
298 
299 	if (result != size) {
300 		dbg("%s - Unable to send config request, "
301 				"request=0x%x size=%d result=%d",
302 				__func__, request, size, result);
303 		if (result > 0)
304 			result = -EPROTO;
305 
306 		return result;
307 	}
308 
309 	return 0;
310 }
311 
312 /*
313  * cp210x_set_config
314  * Writes to the CP210x configuration registers
315  * Values less than 16 bits wide are sent directly
316  * 'size' is specified in bytes.
317  */
318 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
319 		unsigned int *data, int size)
320 {
321 	struct usb_serial *serial = port->serial;
322 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
323 	__le32 *buf;
324 	int result, i, length;
325 
326 	/* Number of integers required to contain the array */
327 	length = (((size - 1) | 3) + 1)/4;
328 
329 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
330 	if (!buf) {
331 		dev_err(&port->dev, "%s - out of memory.\n",
332 				__func__);
333 		return -ENOMEM;
334 	}
335 
336 	/* Array of integers into bytes */
337 	for (i = 0; i < length; i++)
338 		buf[i] = cpu_to_le32(data[i]);
339 
340 	if (size > 2) {
341 		result = usb_control_msg(serial->dev,
342 				usb_sndctrlpipe(serial->dev, 0),
343 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
344 				port_priv->bInterfaceNumber, buf, size,
345 				USB_CTRL_SET_TIMEOUT);
346 	} else {
347 		result = usb_control_msg(serial->dev,
348 				usb_sndctrlpipe(serial->dev, 0),
349 				request, REQTYPE_HOST_TO_DEVICE, data[0],
350 				port_priv->bInterfaceNumber, NULL, 0,
351 				USB_CTRL_SET_TIMEOUT);
352 	}
353 
354 	kfree(buf);
355 
356 	if ((size > 2 && result != size) || result < 0) {
357 		dbg("%s - Unable to send request, "
358 				"request=0x%x size=%d result=%d",
359 				__func__, request, size, result);
360 		if (result > 0)
361 			result = -EPROTO;
362 
363 		return result;
364 	}
365 
366 	return 0;
367 }
368 
369 /*
370  * cp210x_set_config_single
371  * Convenience function for calling cp210x_set_config on single data values
372  * without requiring an integer pointer
373  */
374 static inline int cp210x_set_config_single(struct usb_serial_port *port,
375 		u8 request, unsigned int data)
376 {
377 	return cp210x_set_config(port, request, &data, 2);
378 }
379 
380 /*
381  * cp210x_quantise_baudrate
382  * Quantises the baud rate as per AN205 Table 1
383  */
384 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
385 	if (baud <= 300)
386 		baud = 300;
387 	else if (baud <= 600)      baud = 600;
388 	else if (baud <= 1200)     baud = 1200;
389 	else if (baud <= 1800)     baud = 1800;
390 	else if (baud <= 2400)     baud = 2400;
391 	else if (baud <= 4000)     baud = 4000;
392 	else if (baud <= 4803)     baud = 4800;
393 	else if (baud <= 7207)     baud = 7200;
394 	else if (baud <= 9612)     baud = 9600;
395 	else if (baud <= 14428)    baud = 14400;
396 	else if (baud <= 16062)    baud = 16000;
397 	else if (baud <= 19250)    baud = 19200;
398 	else if (baud <= 28912)    baud = 28800;
399 	else if (baud <= 38601)    baud = 38400;
400 	else if (baud <= 51558)    baud = 51200;
401 	else if (baud <= 56280)    baud = 56000;
402 	else if (baud <= 58053)    baud = 57600;
403 	else if (baud <= 64111)    baud = 64000;
404 	else if (baud <= 77608)    baud = 76800;
405 	else if (baud <= 117028)   baud = 115200;
406 	else if (baud <= 129347)   baud = 128000;
407 	else if (baud <= 156868)   baud = 153600;
408 	else if (baud <= 237832)   baud = 230400;
409 	else if (baud <= 254234)   baud = 250000;
410 	else if (baud <= 273066)   baud = 256000;
411 	else if (baud <= 491520)   baud = 460800;
412 	else if (baud <= 567138)   baud = 500000;
413 	else if (baud <= 670254)   baud = 576000;
414 	else if (baud < 1000000)
415 		baud = 921600;
416 	else if (baud > 2000000)
417 		baud = 2000000;
418 	return baud;
419 }
420 
421 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
422 {
423 	int result;
424 
425 	dbg("%s - port %d", __func__, port->number);
426 
427 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
428 								UART_ENABLE);
429 	if (result) {
430 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
431 		return result;
432 	}
433 
434 	/* Configure the termios structure */
435 	cp210x_get_termios(tty, port);
436 
437 	/* The baud rate must be initialised on cp2104 */
438 	if (tty)
439 		cp210x_change_speed(tty, port, NULL);
440 
441 	return usb_serial_generic_open(tty, port);
442 }
443 
444 static void cp210x_close(struct usb_serial_port *port)
445 {
446 	dbg("%s - port %d", __func__, port->number);
447 
448 	usb_serial_generic_close(port);
449 
450 	mutex_lock(&port->serial->disc_mutex);
451 	if (!port->serial->disconnected)
452 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
453 	mutex_unlock(&port->serial->disc_mutex);
454 }
455 
456 /*
457  * cp210x_get_termios
458  * Reads the baud rate, data bits, parity, stop bits and flow control mode
459  * from the device, corrects any unsupported values, and configures the
460  * termios structure to reflect the state of the device
461  */
462 static void cp210x_get_termios(struct tty_struct *tty,
463 	struct usb_serial_port *port)
464 {
465 	unsigned int baud;
466 
467 	if (tty) {
468 		cp210x_get_termios_port(tty->driver_data,
469 			&tty->termios->c_cflag, &baud);
470 		tty_encode_baud_rate(tty, baud, baud);
471 	}
472 
473 	else {
474 		unsigned int cflag;
475 		cflag = 0;
476 		cp210x_get_termios_port(port, &cflag, &baud);
477 	}
478 }
479 
480 /*
481  * cp210x_get_termios_port
482  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
483  */
484 static void cp210x_get_termios_port(struct usb_serial_port *port,
485 	unsigned int *cflagp, unsigned int *baudp)
486 {
487 	unsigned int cflag, modem_ctl[4];
488 	unsigned int baud;
489 	unsigned int bits;
490 
491 	dbg("%s - port %d", __func__, port->number);
492 
493 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
494 
495 	dbg("%s - baud rate = %d", __func__, baud);
496 	*baudp = baud;
497 
498 	cflag = *cflagp;
499 
500 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
501 	cflag &= ~CSIZE;
502 	switch (bits & BITS_DATA_MASK) {
503 	case BITS_DATA_5:
504 		dbg("%s - data bits = 5", __func__);
505 		cflag |= CS5;
506 		break;
507 	case BITS_DATA_6:
508 		dbg("%s - data bits = 6", __func__);
509 		cflag |= CS6;
510 		break;
511 	case BITS_DATA_7:
512 		dbg("%s - data bits = 7", __func__);
513 		cflag |= CS7;
514 		break;
515 	case BITS_DATA_8:
516 		dbg("%s - data bits = 8", __func__);
517 		cflag |= CS8;
518 		break;
519 	case BITS_DATA_9:
520 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
521 								__func__);
522 		cflag |= CS8;
523 		bits &= ~BITS_DATA_MASK;
524 		bits |= BITS_DATA_8;
525 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
526 		break;
527 	default:
528 		dbg("%s - Unknown number of data bits, using 8", __func__);
529 		cflag |= CS8;
530 		bits &= ~BITS_DATA_MASK;
531 		bits |= BITS_DATA_8;
532 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
533 		break;
534 	}
535 
536 	switch (bits & BITS_PARITY_MASK) {
537 	case BITS_PARITY_NONE:
538 		dbg("%s - parity = NONE", __func__);
539 		cflag &= ~PARENB;
540 		break;
541 	case BITS_PARITY_ODD:
542 		dbg("%s - parity = ODD", __func__);
543 		cflag |= (PARENB|PARODD);
544 		break;
545 	case BITS_PARITY_EVEN:
546 		dbg("%s - parity = EVEN", __func__);
547 		cflag &= ~PARODD;
548 		cflag |= PARENB;
549 		break;
550 	case BITS_PARITY_MARK:
551 		dbg("%s - parity = MARK", __func__);
552 		cflag |= (PARENB|PARODD|CMSPAR);
553 		break;
554 	case BITS_PARITY_SPACE:
555 		dbg("%s - parity = SPACE", __func__);
556 		cflag &= ~PARODD;
557 		cflag |= (PARENB|CMSPAR);
558 		break;
559 	default:
560 		dbg("%s - Unknown parity mode, disabling parity", __func__);
561 		cflag &= ~PARENB;
562 		bits &= ~BITS_PARITY_MASK;
563 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
564 		break;
565 	}
566 
567 	cflag &= ~CSTOPB;
568 	switch (bits & BITS_STOP_MASK) {
569 	case BITS_STOP_1:
570 		dbg("%s - stop bits = 1", __func__);
571 		break;
572 	case BITS_STOP_1_5:
573 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
574 								__func__);
575 		bits &= ~BITS_STOP_MASK;
576 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
577 		break;
578 	case BITS_STOP_2:
579 		dbg("%s - stop bits = 2", __func__);
580 		cflag |= CSTOPB;
581 		break;
582 	default:
583 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
584 								__func__);
585 		bits &= ~BITS_STOP_MASK;
586 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
587 		break;
588 	}
589 
590 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
591 	if (modem_ctl[0] & 0x0008) {
592 		dbg("%s - flow control = CRTSCTS", __func__);
593 		cflag |= CRTSCTS;
594 	} else {
595 		dbg("%s - flow control = NONE", __func__);
596 		cflag &= ~CRTSCTS;
597 	}
598 
599 	*cflagp = cflag;
600 }
601 
602 /*
603  * CP2101 supports the following baud rates:
604  *
605  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
606  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
607  *
608  * CP2102 and CP2103 support the following additional rates:
609  *
610  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
611  *	576000
612  *
613  * The device will map a requested rate to a supported one, but the result
614  * of requests for rates greater than 1053257 is undefined (see AN205).
615  *
616  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
617  * respectively, with an error less than 1%. The actual rates are determined
618  * by
619  *
620  *	div = round(freq / (2 x prescale x request))
621  *	actual = freq / (2 x prescale x div)
622  *
623  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
624  * or 1 otherwise.
625  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
626  * otherwise.
627  */
628 static void cp210x_change_speed(struct tty_struct *tty,
629 		struct usb_serial_port *port, struct ktermios *old_termios)
630 {
631 	u32 baud;
632 
633 	baud = tty->termios->c_ospeed;
634 
635 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
636 	 * or to an arbitrary rate in [1M,2M].
637 	 *
638 	 * NOTE: B0 is not implemented.
639 	 */
640 	baud = cp210x_quantise_baudrate(baud);
641 
642 	dbg("%s - setting baud rate to %u", __func__, baud);
643 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
644 							sizeof(baud))) {
645 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
646 		if (old_termios)
647 			baud = old_termios->c_ospeed;
648 		else
649 			baud = 9600;
650 	}
651 
652 	tty_encode_baud_rate(tty, baud, baud);
653 }
654 
655 static void cp210x_set_termios(struct tty_struct *tty,
656 		struct usb_serial_port *port, struct ktermios *old_termios)
657 {
658 	unsigned int cflag, old_cflag;
659 	unsigned int bits;
660 	unsigned int modem_ctl[4];
661 
662 	dbg("%s - port %d", __func__, port->number);
663 
664 	if (!tty)
665 		return;
666 
667 	cflag = tty->termios->c_cflag;
668 	old_cflag = old_termios->c_cflag;
669 
670 	if (tty->termios->c_ospeed != old_termios->c_ospeed)
671 		cp210x_change_speed(tty, port, old_termios);
672 
673 	/* If the number of data bits is to be updated */
674 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
675 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
676 		bits &= ~BITS_DATA_MASK;
677 		switch (cflag & CSIZE) {
678 		case CS5:
679 			bits |= BITS_DATA_5;
680 			dbg("%s - data bits = 5", __func__);
681 			break;
682 		case CS6:
683 			bits |= BITS_DATA_6;
684 			dbg("%s - data bits = 6", __func__);
685 			break;
686 		case CS7:
687 			bits |= BITS_DATA_7;
688 			dbg("%s - data bits = 7", __func__);
689 			break;
690 		case CS8:
691 			bits |= BITS_DATA_8;
692 			dbg("%s - data bits = 8", __func__);
693 			break;
694 		/*case CS9:
695 			bits |= BITS_DATA_9;
696 			dbg("%s - data bits = 9", __func__);
697 			break;*/
698 		default:
699 			dbg("cp210x driver does not "
700 					"support the number of bits requested,"
701 					" using 8 bit mode");
702 				bits |= BITS_DATA_8;
703 				break;
704 		}
705 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
706 			dbg("Number of data bits requested "
707 					"not supported by device");
708 	}
709 
710 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
711 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
712 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
713 		bits &= ~BITS_PARITY_MASK;
714 		if (cflag & PARENB) {
715 			if (cflag & CMSPAR) {
716 			    if (cflag & PARODD) {
717 				    bits |= BITS_PARITY_MARK;
718 				    dbg("%s - parity = MARK", __func__);
719 			    } else {
720 				    bits |= BITS_PARITY_SPACE;
721 				    dbg("%s - parity = SPACE", __func__);
722 			    }
723 			} else {
724 			    if (cflag & PARODD) {
725 				    bits |= BITS_PARITY_ODD;
726 				    dbg("%s - parity = ODD", __func__);
727 			    } else {
728 				    bits |= BITS_PARITY_EVEN;
729 				    dbg("%s - parity = EVEN", __func__);
730 			    }
731 			}
732 		}
733 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
734 			dbg("Parity mode not supported by device");
735 	}
736 
737 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
738 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
739 		bits &= ~BITS_STOP_MASK;
740 		if (cflag & CSTOPB) {
741 			bits |= BITS_STOP_2;
742 			dbg("%s - stop bits = 2", __func__);
743 		} else {
744 			bits |= BITS_STOP_1;
745 			dbg("%s - stop bits = 1", __func__);
746 		}
747 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
748 			dbg("Number of stop bits requested "
749 					"not supported by device");
750 	}
751 
752 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
753 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
754 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
755 				__func__, modem_ctl[0], modem_ctl[1],
756 				modem_ctl[2], modem_ctl[3]);
757 
758 		if (cflag & CRTSCTS) {
759 			modem_ctl[0] &= ~0x7B;
760 			modem_ctl[0] |= 0x09;
761 			modem_ctl[1] = 0x80;
762 			dbg("%s - flow control = CRTSCTS", __func__);
763 		} else {
764 			modem_ctl[0] &= ~0x7B;
765 			modem_ctl[0] |= 0x01;
766 			modem_ctl[1] |= 0x40;
767 			dbg("%s - flow control = NONE", __func__);
768 		}
769 
770 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
771 				__func__, modem_ctl[0], modem_ctl[1],
772 				modem_ctl[2], modem_ctl[3]);
773 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
774 	}
775 
776 }
777 
778 static int cp210x_tiocmset (struct tty_struct *tty,
779 		unsigned int set, unsigned int clear)
780 {
781 	struct usb_serial_port *port = tty->driver_data;
782 	return cp210x_tiocmset_port(port, set, clear);
783 }
784 
785 static int cp210x_tiocmset_port(struct usb_serial_port *port,
786 		unsigned int set, unsigned int clear)
787 {
788 	unsigned int control = 0;
789 
790 	dbg("%s - port %d", __func__, port->number);
791 
792 	if (set & TIOCM_RTS) {
793 		control |= CONTROL_RTS;
794 		control |= CONTROL_WRITE_RTS;
795 	}
796 	if (set & TIOCM_DTR) {
797 		control |= CONTROL_DTR;
798 		control |= CONTROL_WRITE_DTR;
799 	}
800 	if (clear & TIOCM_RTS) {
801 		control &= ~CONTROL_RTS;
802 		control |= CONTROL_WRITE_RTS;
803 	}
804 	if (clear & TIOCM_DTR) {
805 		control &= ~CONTROL_DTR;
806 		control |= CONTROL_WRITE_DTR;
807 	}
808 
809 	dbg("%s - control = 0x%.4x", __func__, control);
810 
811 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
812 }
813 
814 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
815 {
816 	if (on)
817 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
818 	else
819 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
820 }
821 
822 static int cp210x_tiocmget (struct tty_struct *tty)
823 {
824 	struct usb_serial_port *port = tty->driver_data;
825 	unsigned int control;
826 	int result;
827 
828 	dbg("%s - port %d", __func__, port->number);
829 
830 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
831 
832 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
833 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
834 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
835 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
836 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
837 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
838 
839 	dbg("%s - control = 0x%.2x", __func__, control);
840 
841 	return result;
842 }
843 
844 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
845 {
846 	struct usb_serial_port *port = tty->driver_data;
847 	unsigned int state;
848 
849 	dbg("%s - port %d", __func__, port->number);
850 	if (break_state == 0)
851 		state = BREAK_OFF;
852 	else
853 		state = BREAK_ON;
854 	dbg("%s - turning break %s", __func__,
855 			state == BREAK_OFF ? "off" : "on");
856 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
857 }
858 
859 static int cp210x_startup(struct usb_serial *serial)
860 {
861 	struct cp210x_port_private *port_priv;
862 	int i;
863 
864 	/* cp210x buffers behave strangely unless device is reset */
865 	usb_reset_device(serial->dev);
866 
867 	for (i = 0; i < serial->num_ports; i++) {
868 		port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
869 		if (!port_priv)
870 			return -ENOMEM;
871 
872 		memset(port_priv, 0x00, sizeof(*port_priv));
873 		port_priv->bInterfaceNumber =
874 		    serial->interface->cur_altsetting->desc.bInterfaceNumber;
875 
876 		usb_set_serial_port_data(serial->port[i], port_priv);
877 	}
878 
879 	return 0;
880 }
881 
882 static void cp210x_release(struct usb_serial *serial)
883 {
884 	struct cp210x_port_private *port_priv;
885 	int i;
886 
887 	for (i = 0; i < serial->num_ports; i++) {
888 		port_priv = usb_get_serial_port_data(serial->port[i]);
889 		kfree(port_priv);
890 		usb_set_serial_port_data(serial->port[i], NULL);
891 	}
892 }
893 
894 module_usb_serial_driver(cp210x_driver, serial_drivers);
895 
896 MODULE_DESCRIPTION(DRIVER_DESC);
897 MODULE_VERSION(DRIVER_VERSION);
898 MODULE_LICENSE("GPL");
899 
900 module_param(debug, bool, S_IRUGO | S_IWUSR);
901 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
902