xref: /linux/drivers/usb/serial/cp210x.c (revision 3fcc8f96829776cf181918461923d1e3bbb831a2)
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, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
86 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
87 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
88 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
89 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
90 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
91 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
92 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
93 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
94 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
95 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
96 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
97 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
98 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
99 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
100 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
101 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
102 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
103 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
104 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
105 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
106 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
107 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
108 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
109 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
110 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
111 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
112 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
113 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
114 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
115 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
116 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
117 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
118 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
119 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
120 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
121 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
122 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
123 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
124 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
125 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
126 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
127 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
128 	{ USB_DEVICE(0x10C4, 0xEA80) }, /* Silicon Labs factory default */
129 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
130 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
131 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
132 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
133 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
134 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
135 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
136 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
137 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
138 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
139 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
140 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
141 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
142 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
143 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
144 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
145 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
146 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
147 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
148 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
149 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
150 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
151 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
152 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
153 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
154 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
155 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
156 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
157 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
158 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
159 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
160 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
161 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
162 	{ } /* Terminating Entry */
163 };
164 
165 MODULE_DEVICE_TABLE(usb, id_table);
166 
167 struct cp210x_port_private {
168 	__u8			bInterfaceNumber;
169 };
170 
171 static struct usb_serial_driver cp210x_device = {
172 	.driver = {
173 		.owner =	THIS_MODULE,
174 		.name = 	"cp210x",
175 	},
176 	.id_table		= id_table,
177 	.num_ports		= 1,
178 	.bulk_in_size		= 256,
179 	.bulk_out_size		= 256,
180 	.open			= cp210x_open,
181 	.close			= cp210x_close,
182 	.break_ctl		= cp210x_break_ctl,
183 	.set_termios		= cp210x_set_termios,
184 	.tiocmget 		= cp210x_tiocmget,
185 	.tiocmset		= cp210x_tiocmset,
186 	.attach			= cp210x_startup,
187 	.release		= cp210x_release,
188 	.dtr_rts		= cp210x_dtr_rts
189 };
190 
191 static struct usb_serial_driver * const serial_drivers[] = {
192 	&cp210x_device, NULL
193 };
194 
195 /* Config request types */
196 #define REQTYPE_HOST_TO_INTERFACE	0x41
197 #define REQTYPE_INTERFACE_TO_HOST	0xc1
198 #define REQTYPE_HOST_TO_DEVICE	0x40
199 #define REQTYPE_DEVICE_TO_HOST	0xc0
200 
201 /* Config request codes */
202 #define CP210X_IFC_ENABLE	0x00
203 #define CP210X_SET_BAUDDIV	0x01
204 #define CP210X_GET_BAUDDIV	0x02
205 #define CP210X_SET_LINE_CTL	0x03
206 #define CP210X_GET_LINE_CTL	0x04
207 #define CP210X_SET_BREAK	0x05
208 #define CP210X_IMM_CHAR		0x06
209 #define CP210X_SET_MHS		0x07
210 #define CP210X_GET_MDMSTS	0x08
211 #define CP210X_SET_XON		0x09
212 #define CP210X_SET_XOFF		0x0A
213 #define CP210X_SET_EVENTMASK	0x0B
214 #define CP210X_GET_EVENTMASK	0x0C
215 #define CP210X_SET_CHAR		0x0D
216 #define CP210X_GET_CHARS	0x0E
217 #define CP210X_GET_PROPS	0x0F
218 #define CP210X_GET_COMM_STATUS	0x10
219 #define CP210X_RESET		0x11
220 #define CP210X_PURGE		0x12
221 #define CP210X_SET_FLOW		0x13
222 #define CP210X_GET_FLOW		0x14
223 #define CP210X_EMBED_EVENTS	0x15
224 #define CP210X_GET_EVENTSTATE	0x16
225 #define CP210X_SET_CHARS	0x19
226 #define CP210X_GET_BAUDRATE	0x1D
227 #define CP210X_SET_BAUDRATE	0x1E
228 
229 /* CP210X_IFC_ENABLE */
230 #define UART_ENABLE		0x0001
231 #define UART_DISABLE		0x0000
232 
233 /* CP210X_(SET|GET)_BAUDDIV */
234 #define BAUD_RATE_GEN_FREQ	0x384000
235 
236 /* CP210X_(SET|GET)_LINE_CTL */
237 #define BITS_DATA_MASK		0X0f00
238 #define BITS_DATA_5		0X0500
239 #define BITS_DATA_6		0X0600
240 #define BITS_DATA_7		0X0700
241 #define BITS_DATA_8		0X0800
242 #define BITS_DATA_9		0X0900
243 
244 #define BITS_PARITY_MASK	0x00f0
245 #define BITS_PARITY_NONE	0x0000
246 #define BITS_PARITY_ODD		0x0010
247 #define BITS_PARITY_EVEN	0x0020
248 #define BITS_PARITY_MARK	0x0030
249 #define BITS_PARITY_SPACE	0x0040
250 
251 #define BITS_STOP_MASK		0x000f
252 #define BITS_STOP_1		0x0000
253 #define BITS_STOP_1_5		0x0001
254 #define BITS_STOP_2		0x0002
255 
256 /* CP210X_SET_BREAK */
257 #define BREAK_ON		0x0001
258 #define BREAK_OFF		0x0000
259 
260 /* CP210X_(SET_MHS|GET_MDMSTS) */
261 #define CONTROL_DTR		0x0001
262 #define CONTROL_RTS		0x0002
263 #define CONTROL_CTS		0x0010
264 #define CONTROL_DSR		0x0020
265 #define CONTROL_RING		0x0040
266 #define CONTROL_DCD		0x0080
267 #define CONTROL_WRITE_DTR	0x0100
268 #define CONTROL_WRITE_RTS	0x0200
269 
270 /*
271  * cp210x_get_config
272  * Reads from the CP210x configuration registers
273  * 'size' is specified in bytes.
274  * 'data' is a pointer to a pre-allocated array of integers large
275  * enough to hold 'size' bytes (with 4 bytes to each integer)
276  */
277 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
278 		unsigned int *data, int size)
279 {
280 	struct usb_serial *serial = port->serial;
281 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
282 	__le32 *buf;
283 	int result, i, length;
284 
285 	/* Number of integers required to contain the array */
286 	length = (((size - 1) | 3) + 1)/4;
287 
288 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
289 	if (!buf) {
290 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
291 		return -ENOMEM;
292 	}
293 
294 	/* Issue the request, attempting to read 'size' bytes */
295 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
296 				request, REQTYPE_INTERFACE_TO_HOST, 0x0000,
297 				port_priv->bInterfaceNumber, buf, size,
298 				USB_CTRL_GET_TIMEOUT);
299 
300 	/* Convert data into an array of integers */
301 	for (i = 0; i < length; i++)
302 		data[i] = le32_to_cpu(buf[i]);
303 
304 	kfree(buf);
305 
306 	if (result != size) {
307 		dbg("%s - Unable to send config request, "
308 				"request=0x%x size=%d result=%d",
309 				__func__, request, size, result);
310 		if (result > 0)
311 			result = -EPROTO;
312 
313 		return result;
314 	}
315 
316 	return 0;
317 }
318 
319 /*
320  * cp210x_set_config
321  * Writes to the CP210x configuration registers
322  * Values less than 16 bits wide are sent directly
323  * 'size' is specified in bytes.
324  */
325 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
326 		unsigned int *data, int size)
327 {
328 	struct usb_serial *serial = port->serial;
329 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
330 	__le32 *buf;
331 	int result, i, length;
332 
333 	/* Number of integers required to contain the array */
334 	length = (((size - 1) | 3) + 1)/4;
335 
336 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
337 	if (!buf) {
338 		dev_err(&port->dev, "%s - out of memory.\n",
339 				__func__);
340 		return -ENOMEM;
341 	}
342 
343 	/* Array of integers into bytes */
344 	for (i = 0; i < length; i++)
345 		buf[i] = cpu_to_le32(data[i]);
346 
347 	if (size > 2) {
348 		result = usb_control_msg(serial->dev,
349 				usb_sndctrlpipe(serial->dev, 0),
350 				request, REQTYPE_HOST_TO_INTERFACE, 0x0000,
351 				port_priv->bInterfaceNumber, buf, size,
352 				USB_CTRL_SET_TIMEOUT);
353 	} else {
354 		result = usb_control_msg(serial->dev,
355 				usb_sndctrlpipe(serial->dev, 0),
356 				request, REQTYPE_HOST_TO_INTERFACE, data[0],
357 				port_priv->bInterfaceNumber, NULL, 0,
358 				USB_CTRL_SET_TIMEOUT);
359 	}
360 
361 	kfree(buf);
362 
363 	if ((size > 2 && result != size) || result < 0) {
364 		dbg("%s - Unable to send request, "
365 				"request=0x%x size=%d result=%d",
366 				__func__, request, size, result);
367 		if (result > 0)
368 			result = -EPROTO;
369 
370 		return result;
371 	}
372 
373 	return 0;
374 }
375 
376 /*
377  * cp210x_set_config_single
378  * Convenience function for calling cp210x_set_config on single data values
379  * without requiring an integer pointer
380  */
381 static inline int cp210x_set_config_single(struct usb_serial_port *port,
382 		u8 request, unsigned int data)
383 {
384 	return cp210x_set_config(port, request, &data, 2);
385 }
386 
387 /*
388  * cp210x_quantise_baudrate
389  * Quantises the baud rate as per AN205 Table 1
390  */
391 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
392 	if (baud <= 300)
393 		baud = 300;
394 	else if (baud <= 600)      baud = 600;
395 	else if (baud <= 1200)     baud = 1200;
396 	else if (baud <= 1800)     baud = 1800;
397 	else if (baud <= 2400)     baud = 2400;
398 	else if (baud <= 4000)     baud = 4000;
399 	else if (baud <= 4803)     baud = 4800;
400 	else if (baud <= 7207)     baud = 7200;
401 	else if (baud <= 9612)     baud = 9600;
402 	else if (baud <= 14428)    baud = 14400;
403 	else if (baud <= 16062)    baud = 16000;
404 	else if (baud <= 19250)    baud = 19200;
405 	else if (baud <= 28912)    baud = 28800;
406 	else if (baud <= 38601)    baud = 38400;
407 	else if (baud <= 51558)    baud = 51200;
408 	else if (baud <= 56280)    baud = 56000;
409 	else if (baud <= 58053)    baud = 57600;
410 	else if (baud <= 64111)    baud = 64000;
411 	else if (baud <= 77608)    baud = 76800;
412 	else if (baud <= 117028)   baud = 115200;
413 	else if (baud <= 129347)   baud = 128000;
414 	else if (baud <= 156868)   baud = 153600;
415 	else if (baud <= 237832)   baud = 230400;
416 	else if (baud <= 254234)   baud = 250000;
417 	else if (baud <= 273066)   baud = 256000;
418 	else if (baud <= 491520)   baud = 460800;
419 	else if (baud <= 567138)   baud = 500000;
420 	else if (baud <= 670254)   baud = 576000;
421 	else if (baud < 1000000)
422 		baud = 921600;
423 	else if (baud > 2000000)
424 		baud = 2000000;
425 	return baud;
426 }
427 
428 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
429 {
430 	int result;
431 
432 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
433 								UART_ENABLE);
434 	if (result) {
435 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
436 		return result;
437 	}
438 
439 	/* Configure the termios structure */
440 	cp210x_get_termios(tty, port);
441 
442 	/* The baud rate must be initialised on cp2104 */
443 	if (tty)
444 		cp210x_change_speed(tty, port, NULL);
445 
446 	return usb_serial_generic_open(tty, port);
447 }
448 
449 static void cp210x_close(struct usb_serial_port *port)
450 {
451 	usb_serial_generic_close(port);
452 
453 	mutex_lock(&port->serial->disc_mutex);
454 	if (!port->serial->disconnected)
455 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
456 	mutex_unlock(&port->serial->disc_mutex);
457 }
458 
459 /*
460  * cp210x_get_termios
461  * Reads the baud rate, data bits, parity, stop bits and flow control mode
462  * from the device, corrects any unsupported values, and configures the
463  * termios structure to reflect the state of the device
464  */
465 static void cp210x_get_termios(struct tty_struct *tty,
466 	struct usb_serial_port *port)
467 {
468 	unsigned int baud;
469 
470 	if (tty) {
471 		cp210x_get_termios_port(tty->driver_data,
472 			&tty->termios->c_cflag, &baud);
473 		tty_encode_baud_rate(tty, baud, baud);
474 	}
475 
476 	else {
477 		unsigned int cflag;
478 		cflag = 0;
479 		cp210x_get_termios_port(port, &cflag, &baud);
480 	}
481 }
482 
483 /*
484  * cp210x_get_termios_port
485  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
486  */
487 static void cp210x_get_termios_port(struct usb_serial_port *port,
488 	unsigned int *cflagp, unsigned int *baudp)
489 {
490 	unsigned int cflag, modem_ctl[4];
491 	unsigned int baud;
492 	unsigned int bits;
493 
494 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
495 
496 	dbg("%s - baud rate = %d", __func__, baud);
497 	*baudp = baud;
498 
499 	cflag = *cflagp;
500 
501 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
502 	cflag &= ~CSIZE;
503 	switch (bits & BITS_DATA_MASK) {
504 	case BITS_DATA_5:
505 		dbg("%s - data bits = 5", __func__);
506 		cflag |= CS5;
507 		break;
508 	case BITS_DATA_6:
509 		dbg("%s - data bits = 6", __func__);
510 		cflag |= CS6;
511 		break;
512 	case BITS_DATA_7:
513 		dbg("%s - data bits = 7", __func__);
514 		cflag |= CS7;
515 		break;
516 	case BITS_DATA_8:
517 		dbg("%s - data bits = 8", __func__);
518 		cflag |= CS8;
519 		break;
520 	case BITS_DATA_9:
521 		dbg("%s - data bits = 9 (not supported, using 8 data bits)",
522 								__func__);
523 		cflag |= CS8;
524 		bits &= ~BITS_DATA_MASK;
525 		bits |= BITS_DATA_8;
526 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
527 		break;
528 	default:
529 		dbg("%s - Unknown number of data bits, using 8", __func__);
530 		cflag |= CS8;
531 		bits &= ~BITS_DATA_MASK;
532 		bits |= BITS_DATA_8;
533 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
534 		break;
535 	}
536 
537 	switch (bits & BITS_PARITY_MASK) {
538 	case BITS_PARITY_NONE:
539 		dbg("%s - parity = NONE", __func__);
540 		cflag &= ~PARENB;
541 		break;
542 	case BITS_PARITY_ODD:
543 		dbg("%s - parity = ODD", __func__);
544 		cflag |= (PARENB|PARODD);
545 		break;
546 	case BITS_PARITY_EVEN:
547 		dbg("%s - parity = EVEN", __func__);
548 		cflag &= ~PARODD;
549 		cflag |= PARENB;
550 		break;
551 	case BITS_PARITY_MARK:
552 		dbg("%s - parity = MARK", __func__);
553 		cflag |= (PARENB|PARODD|CMSPAR);
554 		break;
555 	case BITS_PARITY_SPACE:
556 		dbg("%s - parity = SPACE", __func__);
557 		cflag &= ~PARODD;
558 		cflag |= (PARENB|CMSPAR);
559 		break;
560 	default:
561 		dbg("%s - Unknown parity mode, disabling parity", __func__);
562 		cflag &= ~PARENB;
563 		bits &= ~BITS_PARITY_MASK;
564 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
565 		break;
566 	}
567 
568 	cflag &= ~CSTOPB;
569 	switch (bits & BITS_STOP_MASK) {
570 	case BITS_STOP_1:
571 		dbg("%s - stop bits = 1", __func__);
572 		break;
573 	case BITS_STOP_1_5:
574 		dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
575 								__func__);
576 		bits &= ~BITS_STOP_MASK;
577 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
578 		break;
579 	case BITS_STOP_2:
580 		dbg("%s - stop bits = 2", __func__);
581 		cflag |= CSTOPB;
582 		break;
583 	default:
584 		dbg("%s - Unknown number of stop bits, using 1 stop bit",
585 								__func__);
586 		bits &= ~BITS_STOP_MASK;
587 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
588 		break;
589 	}
590 
591 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
592 	if (modem_ctl[0] & 0x0008) {
593 		dbg("%s - flow control = CRTSCTS", __func__);
594 		cflag |= CRTSCTS;
595 	} else {
596 		dbg("%s - flow control = NONE", __func__);
597 		cflag &= ~CRTSCTS;
598 	}
599 
600 	*cflagp = cflag;
601 }
602 
603 /*
604  * CP2101 supports the following baud rates:
605  *
606  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
607  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
608  *
609  * CP2102 and CP2103 support the following additional rates:
610  *
611  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
612  *	576000
613  *
614  * The device will map a requested rate to a supported one, but the result
615  * of requests for rates greater than 1053257 is undefined (see AN205).
616  *
617  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
618  * respectively, with an error less than 1%. The actual rates are determined
619  * by
620  *
621  *	div = round(freq / (2 x prescale x request))
622  *	actual = freq / (2 x prescale x div)
623  *
624  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
625  * or 1 otherwise.
626  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
627  * otherwise.
628  */
629 static void cp210x_change_speed(struct tty_struct *tty,
630 		struct usb_serial_port *port, struct ktermios *old_termios)
631 {
632 	u32 baud;
633 
634 	baud = tty->termios->c_ospeed;
635 
636 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
637 	 * or to an arbitrary rate in [1M,2M].
638 	 *
639 	 * NOTE: B0 is not implemented.
640 	 */
641 	baud = cp210x_quantise_baudrate(baud);
642 
643 	dbg("%s - setting baud rate to %u", __func__, baud);
644 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
645 							sizeof(baud))) {
646 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
647 		if (old_termios)
648 			baud = old_termios->c_ospeed;
649 		else
650 			baud = 9600;
651 	}
652 
653 	tty_encode_baud_rate(tty, baud, baud);
654 }
655 
656 static void cp210x_set_termios(struct tty_struct *tty,
657 		struct usb_serial_port *port, struct ktermios *old_termios)
658 {
659 	unsigned int cflag, old_cflag;
660 	unsigned int bits;
661 	unsigned int modem_ctl[4];
662 
663 	dbg("%s - port %d", __func__, port->number);
664 
665 	if (!tty)
666 		return;
667 
668 	cflag = tty->termios->c_cflag;
669 	old_cflag = old_termios->c_cflag;
670 
671 	if (tty->termios->c_ospeed != old_termios->c_ospeed)
672 		cp210x_change_speed(tty, port, old_termios);
673 
674 	/* If the number of data bits is to be updated */
675 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
676 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
677 		bits &= ~BITS_DATA_MASK;
678 		switch (cflag & CSIZE) {
679 		case CS5:
680 			bits |= BITS_DATA_5;
681 			dbg("%s - data bits = 5", __func__);
682 			break;
683 		case CS6:
684 			bits |= BITS_DATA_6;
685 			dbg("%s - data bits = 6", __func__);
686 			break;
687 		case CS7:
688 			bits |= BITS_DATA_7;
689 			dbg("%s - data bits = 7", __func__);
690 			break;
691 		case CS8:
692 			bits |= BITS_DATA_8;
693 			dbg("%s - data bits = 8", __func__);
694 			break;
695 		/*case CS9:
696 			bits |= BITS_DATA_9;
697 			dbg("%s - data bits = 9", __func__);
698 			break;*/
699 		default:
700 			dbg("cp210x driver does not "
701 					"support the number of bits requested,"
702 					" using 8 bit mode");
703 				bits |= BITS_DATA_8;
704 				break;
705 		}
706 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
707 			dbg("Number of data bits requested "
708 					"not supported by device");
709 	}
710 
711 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
712 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
713 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
714 		bits &= ~BITS_PARITY_MASK;
715 		if (cflag & PARENB) {
716 			if (cflag & CMSPAR) {
717 			    if (cflag & PARODD) {
718 				    bits |= BITS_PARITY_MARK;
719 				    dbg("%s - parity = MARK", __func__);
720 			    } else {
721 				    bits |= BITS_PARITY_SPACE;
722 				    dbg("%s - parity = SPACE", __func__);
723 			    }
724 			} else {
725 			    if (cflag & PARODD) {
726 				    bits |= BITS_PARITY_ODD;
727 				    dbg("%s - parity = ODD", __func__);
728 			    } else {
729 				    bits |= BITS_PARITY_EVEN;
730 				    dbg("%s - parity = EVEN", __func__);
731 			    }
732 			}
733 		}
734 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
735 			dbg("Parity mode not supported by device");
736 	}
737 
738 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
739 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
740 		bits &= ~BITS_STOP_MASK;
741 		if (cflag & CSTOPB) {
742 			bits |= BITS_STOP_2;
743 			dbg("%s - stop bits = 2", __func__);
744 		} else {
745 			bits |= BITS_STOP_1;
746 			dbg("%s - stop bits = 1", __func__);
747 		}
748 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
749 			dbg("Number of stop bits requested "
750 					"not supported by device");
751 	}
752 
753 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
754 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
755 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
756 				__func__, modem_ctl[0], modem_ctl[1],
757 				modem_ctl[2], modem_ctl[3]);
758 
759 		if (cflag & CRTSCTS) {
760 			modem_ctl[0] &= ~0x7B;
761 			modem_ctl[0] |= 0x09;
762 			modem_ctl[1] = 0x80;
763 			dbg("%s - flow control = CRTSCTS", __func__);
764 		} else {
765 			modem_ctl[0] &= ~0x7B;
766 			modem_ctl[0] |= 0x01;
767 			modem_ctl[1] |= 0x40;
768 			dbg("%s - flow control = NONE", __func__);
769 		}
770 
771 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
772 				__func__, modem_ctl[0], modem_ctl[1],
773 				modem_ctl[2], modem_ctl[3]);
774 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
775 	}
776 
777 }
778 
779 static int cp210x_tiocmset (struct tty_struct *tty,
780 		unsigned int set, unsigned int clear)
781 {
782 	struct usb_serial_port *port = tty->driver_data;
783 	return cp210x_tiocmset_port(port, set, clear);
784 }
785 
786 static int cp210x_tiocmset_port(struct usb_serial_port *port,
787 		unsigned int set, unsigned int clear)
788 {
789 	unsigned int control = 0;
790 
791 	if (set & TIOCM_RTS) {
792 		control |= CONTROL_RTS;
793 		control |= CONTROL_WRITE_RTS;
794 	}
795 	if (set & TIOCM_DTR) {
796 		control |= CONTROL_DTR;
797 		control |= CONTROL_WRITE_DTR;
798 	}
799 	if (clear & TIOCM_RTS) {
800 		control &= ~CONTROL_RTS;
801 		control |= CONTROL_WRITE_RTS;
802 	}
803 	if (clear & TIOCM_DTR) {
804 		control &= ~CONTROL_DTR;
805 		control |= CONTROL_WRITE_DTR;
806 	}
807 
808 	dbg("%s - control = 0x%.4x", __func__, control);
809 
810 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
811 }
812 
813 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
814 {
815 	if (on)
816 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
817 	else
818 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
819 }
820 
821 static int cp210x_tiocmget (struct tty_struct *tty)
822 {
823 	struct usb_serial_port *port = tty->driver_data;
824 	unsigned int control;
825 	int result;
826 
827 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
828 
829 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
830 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
831 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
832 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
833 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
834 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
835 
836 	dbg("%s - control = 0x%.2x", __func__, control);
837 
838 	return result;
839 }
840 
841 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
842 {
843 	struct usb_serial_port *port = tty->driver_data;
844 	unsigned int state;
845 
846 	if (break_state == 0)
847 		state = BREAK_OFF;
848 	else
849 		state = BREAK_ON;
850 	dbg("%s - turning break %s", __func__,
851 			state == BREAK_OFF ? "off" : "on");
852 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
853 }
854 
855 static int cp210x_startup(struct usb_serial *serial)
856 {
857 	struct cp210x_port_private *port_priv;
858 	int i;
859 
860 	/* cp210x buffers behave strangely unless device is reset */
861 	usb_reset_device(serial->dev);
862 
863 	for (i = 0; i < serial->num_ports; i++) {
864 		port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
865 		if (!port_priv)
866 			return -ENOMEM;
867 
868 		memset(port_priv, 0x00, sizeof(*port_priv));
869 		port_priv->bInterfaceNumber =
870 		    serial->interface->cur_altsetting->desc.bInterfaceNumber;
871 
872 		usb_set_serial_port_data(serial->port[i], port_priv);
873 	}
874 
875 	return 0;
876 }
877 
878 static void cp210x_release(struct usb_serial *serial)
879 {
880 	struct cp210x_port_private *port_priv;
881 	int i;
882 
883 	for (i = 0; i < serial->num_ports; i++) {
884 		port_priv = usb_get_serial_port_data(serial->port[i]);
885 		kfree(port_priv);
886 		usb_set_serial_port_data(serial->port[i], NULL);
887 	}
888 }
889 
890 module_usb_serial_driver(serial_drivers, id_table);
891 
892 MODULE_DESCRIPTION(DRIVER_DESC);
893 MODULE_VERSION(DRIVER_VERSION);
894 MODULE_LICENSE("GPL");
895 
896 module_param(debug, bool, S_IRUGO | S_IWUSR);
897 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
898