xref: /linux/drivers/usb/serial/cp210x.c (revision 660f3b1410d327e8cd29adb5b834caa66ebbd7d4)
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 		dev_dbg(&port->dev, "%s - Unable to send config request, request=0x%x size=%d result=%d\n",
308 			__func__, request, size, result);
309 		if (result > 0)
310 			result = -EPROTO;
311 
312 		return result;
313 	}
314 
315 	return 0;
316 }
317 
318 /*
319  * cp210x_set_config
320  * Writes to the CP210x configuration registers
321  * Values less than 16 bits wide are sent directly
322  * 'size' is specified in bytes.
323  */
324 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
325 		unsigned int *data, int size)
326 {
327 	struct usb_serial *serial = port->serial;
328 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
329 	__le32 *buf;
330 	int result, i, length;
331 
332 	/* Number of integers required to contain the array */
333 	length = (((size - 1) | 3) + 1)/4;
334 
335 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
336 	if (!buf) {
337 		dev_err(&port->dev, "%s - out of memory.\n",
338 				__func__);
339 		return -ENOMEM;
340 	}
341 
342 	/* Array of integers into bytes */
343 	for (i = 0; i < length; i++)
344 		buf[i] = cpu_to_le32(data[i]);
345 
346 	if (size > 2) {
347 		result = usb_control_msg(serial->dev,
348 				usb_sndctrlpipe(serial->dev, 0),
349 				request, REQTYPE_HOST_TO_INTERFACE, 0x0000,
350 				port_priv->bInterfaceNumber, buf, size,
351 				USB_CTRL_SET_TIMEOUT);
352 	} else {
353 		result = usb_control_msg(serial->dev,
354 				usb_sndctrlpipe(serial->dev, 0),
355 				request, REQTYPE_HOST_TO_INTERFACE, data[0],
356 				port_priv->bInterfaceNumber, NULL, 0,
357 				USB_CTRL_SET_TIMEOUT);
358 	}
359 
360 	kfree(buf);
361 
362 	if ((size > 2 && result != size) || result < 0) {
363 		dev_dbg(&port->dev, "%s - Unable to send request, request=0x%x size=%d result=%d\n",
364 			__func__, request, size, result);
365 		if (result > 0)
366 			result = -EPROTO;
367 
368 		return result;
369 	}
370 
371 	return 0;
372 }
373 
374 /*
375  * cp210x_set_config_single
376  * Convenience function for calling cp210x_set_config on single data values
377  * without requiring an integer pointer
378  */
379 static inline int cp210x_set_config_single(struct usb_serial_port *port,
380 		u8 request, unsigned int data)
381 {
382 	return cp210x_set_config(port, request, &data, 2);
383 }
384 
385 /*
386  * cp210x_quantise_baudrate
387  * Quantises the baud rate as per AN205 Table 1
388  */
389 static unsigned int cp210x_quantise_baudrate(unsigned int baud) {
390 	if (baud <= 300)
391 		baud = 300;
392 	else if (baud <= 600)      baud = 600;
393 	else if (baud <= 1200)     baud = 1200;
394 	else if (baud <= 1800)     baud = 1800;
395 	else if (baud <= 2400)     baud = 2400;
396 	else if (baud <= 4000)     baud = 4000;
397 	else if (baud <= 4803)     baud = 4800;
398 	else if (baud <= 7207)     baud = 7200;
399 	else if (baud <= 9612)     baud = 9600;
400 	else if (baud <= 14428)    baud = 14400;
401 	else if (baud <= 16062)    baud = 16000;
402 	else if (baud <= 19250)    baud = 19200;
403 	else if (baud <= 28912)    baud = 28800;
404 	else if (baud <= 38601)    baud = 38400;
405 	else if (baud <= 51558)    baud = 51200;
406 	else if (baud <= 56280)    baud = 56000;
407 	else if (baud <= 58053)    baud = 57600;
408 	else if (baud <= 64111)    baud = 64000;
409 	else if (baud <= 77608)    baud = 76800;
410 	else if (baud <= 117028)   baud = 115200;
411 	else if (baud <= 129347)   baud = 128000;
412 	else if (baud <= 156868)   baud = 153600;
413 	else if (baud <= 237832)   baud = 230400;
414 	else if (baud <= 254234)   baud = 250000;
415 	else if (baud <= 273066)   baud = 256000;
416 	else if (baud <= 491520)   baud = 460800;
417 	else if (baud <= 567138)   baud = 500000;
418 	else if (baud <= 670254)   baud = 576000;
419 	else if (baud < 1000000)
420 		baud = 921600;
421 	else if (baud > 2000000)
422 		baud = 2000000;
423 	return baud;
424 }
425 
426 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
427 {
428 	int result;
429 
430 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
431 								UART_ENABLE);
432 	if (result) {
433 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
434 		return result;
435 	}
436 
437 	/* Configure the termios structure */
438 	cp210x_get_termios(tty, port);
439 
440 	/* The baud rate must be initialised on cp2104 */
441 	if (tty)
442 		cp210x_change_speed(tty, port, NULL);
443 
444 	return usb_serial_generic_open(tty, port);
445 }
446 
447 static void cp210x_close(struct usb_serial_port *port)
448 {
449 	usb_serial_generic_close(port);
450 
451 	mutex_lock(&port->serial->disc_mutex);
452 	if (!port->serial->disconnected)
453 		cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
454 	mutex_unlock(&port->serial->disc_mutex);
455 }
456 
457 /*
458  * cp210x_get_termios
459  * Reads the baud rate, data bits, parity, stop bits and flow control mode
460  * from the device, corrects any unsupported values, and configures the
461  * termios structure to reflect the state of the device
462  */
463 static void cp210x_get_termios(struct tty_struct *tty,
464 	struct usb_serial_port *port)
465 {
466 	unsigned int baud;
467 
468 	if (tty) {
469 		cp210x_get_termios_port(tty->driver_data,
470 			&tty->termios->c_cflag, &baud);
471 		tty_encode_baud_rate(tty, baud, baud);
472 	}
473 
474 	else {
475 		unsigned int cflag;
476 		cflag = 0;
477 		cp210x_get_termios_port(port, &cflag, &baud);
478 	}
479 }
480 
481 /*
482  * cp210x_get_termios_port
483  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
484  */
485 static void cp210x_get_termios_port(struct usb_serial_port *port,
486 	unsigned int *cflagp, unsigned int *baudp)
487 {
488 	struct device *dev = &port->dev;
489 	unsigned int cflag, modem_ctl[4];
490 	unsigned int baud;
491 	unsigned int bits;
492 
493 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
494 
495 	dev_dbg(dev, "%s - baud rate = %d\n", __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 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
505 		cflag |= CS5;
506 		break;
507 	case BITS_DATA_6:
508 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
509 		cflag |= CS6;
510 		break;
511 	case BITS_DATA_7:
512 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
513 		cflag |= CS7;
514 		break;
515 	case BITS_DATA_8:
516 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
517 		cflag |= CS8;
518 		break;
519 	case BITS_DATA_9:
520 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
521 		cflag |= CS8;
522 		bits &= ~BITS_DATA_MASK;
523 		bits |= BITS_DATA_8;
524 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
525 		break;
526 	default:
527 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
528 		cflag |= CS8;
529 		bits &= ~BITS_DATA_MASK;
530 		bits |= BITS_DATA_8;
531 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
532 		break;
533 	}
534 
535 	switch (bits & BITS_PARITY_MASK) {
536 	case BITS_PARITY_NONE:
537 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
538 		cflag &= ~PARENB;
539 		break;
540 	case BITS_PARITY_ODD:
541 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
542 		cflag |= (PARENB|PARODD);
543 		break;
544 	case BITS_PARITY_EVEN:
545 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
546 		cflag &= ~PARODD;
547 		cflag |= PARENB;
548 		break;
549 	case BITS_PARITY_MARK:
550 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
551 		cflag |= (PARENB|PARODD|CMSPAR);
552 		break;
553 	case BITS_PARITY_SPACE:
554 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
555 		cflag &= ~PARODD;
556 		cflag |= (PARENB|CMSPAR);
557 		break;
558 	default:
559 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
560 		cflag &= ~PARENB;
561 		bits &= ~BITS_PARITY_MASK;
562 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
563 		break;
564 	}
565 
566 	cflag &= ~CSTOPB;
567 	switch (bits & BITS_STOP_MASK) {
568 	case BITS_STOP_1:
569 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
570 		break;
571 	case BITS_STOP_1_5:
572 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
573 		bits &= ~BITS_STOP_MASK;
574 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
575 		break;
576 	case BITS_STOP_2:
577 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
578 		cflag |= CSTOPB;
579 		break;
580 	default:
581 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
582 		bits &= ~BITS_STOP_MASK;
583 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
584 		break;
585 	}
586 
587 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
588 	if (modem_ctl[0] & 0x0008) {
589 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
590 		cflag |= CRTSCTS;
591 	} else {
592 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
593 		cflag &= ~CRTSCTS;
594 	}
595 
596 	*cflagp = cflag;
597 }
598 
599 /*
600  * CP2101 supports the following baud rates:
601  *
602  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
603  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
604  *
605  * CP2102 and CP2103 support the following additional rates:
606  *
607  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
608  *	576000
609  *
610  * The device will map a requested rate to a supported one, but the result
611  * of requests for rates greater than 1053257 is undefined (see AN205).
612  *
613  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
614  * respectively, with an error less than 1%. The actual rates are determined
615  * by
616  *
617  *	div = round(freq / (2 x prescale x request))
618  *	actual = freq / (2 x prescale x div)
619  *
620  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
621  * or 1 otherwise.
622  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
623  * otherwise.
624  */
625 static void cp210x_change_speed(struct tty_struct *tty,
626 		struct usb_serial_port *port, struct ktermios *old_termios)
627 {
628 	u32 baud;
629 
630 	baud = tty->termios->c_ospeed;
631 
632 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
633 	 * or to an arbitrary rate in [1M,2M].
634 	 *
635 	 * NOTE: B0 is not implemented.
636 	 */
637 	baud = cp210x_quantise_baudrate(baud);
638 
639 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
640 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
641 							sizeof(baud))) {
642 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
643 		if (old_termios)
644 			baud = old_termios->c_ospeed;
645 		else
646 			baud = 9600;
647 	}
648 
649 	tty_encode_baud_rate(tty, baud, baud);
650 }
651 
652 static void cp210x_set_termios(struct tty_struct *tty,
653 		struct usb_serial_port *port, struct ktermios *old_termios)
654 {
655 	struct device *dev = &port->dev;
656 	unsigned int cflag, old_cflag;
657 	unsigned int bits;
658 	unsigned int modem_ctl[4];
659 
660 	dev_dbg(dev, "%s - port %d\n", __func__, port->number);
661 
662 	if (!tty)
663 		return;
664 
665 	cflag = tty->termios->c_cflag;
666 	old_cflag = old_termios->c_cflag;
667 
668 	if (tty->termios->c_ospeed != old_termios->c_ospeed)
669 		cp210x_change_speed(tty, port, old_termios);
670 
671 	/* If the number of data bits is to be updated */
672 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
673 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
674 		bits &= ~BITS_DATA_MASK;
675 		switch (cflag & CSIZE) {
676 		case CS5:
677 			bits |= BITS_DATA_5;
678 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
679 			break;
680 		case CS6:
681 			bits |= BITS_DATA_6;
682 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
683 			break;
684 		case CS7:
685 			bits |= BITS_DATA_7;
686 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
687 			break;
688 		case CS8:
689 			bits |= BITS_DATA_8;
690 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
691 			break;
692 		/*case CS9:
693 			bits |= BITS_DATA_9;
694 			dev_dbg(dev, "%s - data bits = 9\n", __func__);
695 			break;*/
696 		default:
697 			dev_dbg(dev, "cp210x driver does not support the number of bits requested, using 8 bit mode\n");
698 				bits |= BITS_DATA_8;
699 				break;
700 		}
701 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
702 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
703 	}
704 
705 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
706 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
707 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
708 		bits &= ~BITS_PARITY_MASK;
709 		if (cflag & PARENB) {
710 			if (cflag & CMSPAR) {
711 				if (cflag & PARODD) {
712 					bits |= BITS_PARITY_MARK;
713 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
714 				} else {
715 					bits |= BITS_PARITY_SPACE;
716 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
717 				}
718 			} else {
719 				if (cflag & PARODD) {
720 					bits |= BITS_PARITY_ODD;
721 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
722 				} else {
723 					bits |= BITS_PARITY_EVEN;
724 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
725 				}
726 			}
727 		}
728 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
729 			dev_dbg(dev, "Parity mode not supported by device\n");
730 	}
731 
732 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
733 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
734 		bits &= ~BITS_STOP_MASK;
735 		if (cflag & CSTOPB) {
736 			bits |= BITS_STOP_2;
737 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
738 		} else {
739 			bits |= BITS_STOP_1;
740 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
741 		}
742 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
743 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
744 	}
745 
746 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
747 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
748 		dev_dbg(dev, "%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
749 			__func__, modem_ctl[0], modem_ctl[1],
750 			modem_ctl[2], modem_ctl[3]);
751 
752 		if (cflag & CRTSCTS) {
753 			modem_ctl[0] &= ~0x7B;
754 			modem_ctl[0] |= 0x09;
755 			modem_ctl[1] = 0x80;
756 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
757 		} else {
758 			modem_ctl[0] &= ~0x7B;
759 			modem_ctl[0] |= 0x01;
760 			modem_ctl[1] |= 0x40;
761 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
762 		}
763 
764 		dev_dbg(dev, "%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
765 			__func__, modem_ctl[0], modem_ctl[1],
766 			modem_ctl[2], modem_ctl[3]);
767 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
768 	}
769 
770 }
771 
772 static int cp210x_tiocmset (struct tty_struct *tty,
773 		unsigned int set, unsigned int clear)
774 {
775 	struct usb_serial_port *port = tty->driver_data;
776 	return cp210x_tiocmset_port(port, set, clear);
777 }
778 
779 static int cp210x_tiocmset_port(struct usb_serial_port *port,
780 		unsigned int set, unsigned int clear)
781 {
782 	unsigned int control = 0;
783 
784 	if (set & TIOCM_RTS) {
785 		control |= CONTROL_RTS;
786 		control |= CONTROL_WRITE_RTS;
787 	}
788 	if (set & TIOCM_DTR) {
789 		control |= CONTROL_DTR;
790 		control |= CONTROL_WRITE_DTR;
791 	}
792 	if (clear & TIOCM_RTS) {
793 		control &= ~CONTROL_RTS;
794 		control |= CONTROL_WRITE_RTS;
795 	}
796 	if (clear & TIOCM_DTR) {
797 		control &= ~CONTROL_DTR;
798 		control |= CONTROL_WRITE_DTR;
799 	}
800 
801 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
802 
803 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
804 }
805 
806 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
807 {
808 	if (on)
809 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
810 	else
811 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
812 }
813 
814 static int cp210x_tiocmget (struct tty_struct *tty)
815 {
816 	struct usb_serial_port *port = tty->driver_data;
817 	unsigned int control;
818 	int result;
819 
820 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
821 
822 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
823 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
824 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
825 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
826 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
827 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
828 
829 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
830 
831 	return result;
832 }
833 
834 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
835 {
836 	struct usb_serial_port *port = tty->driver_data;
837 	unsigned int state;
838 
839 	if (break_state == 0)
840 		state = BREAK_OFF;
841 	else
842 		state = BREAK_ON;
843 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
844 		state == BREAK_OFF ? "off" : "on");
845 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
846 }
847 
848 static int cp210x_startup(struct usb_serial *serial)
849 {
850 	struct cp210x_port_private *port_priv;
851 	int i;
852 
853 	/* cp210x buffers behave strangely unless device is reset */
854 	usb_reset_device(serial->dev);
855 
856 	for (i = 0; i < serial->num_ports; i++) {
857 		port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
858 		if (!port_priv)
859 			return -ENOMEM;
860 
861 		port_priv->bInterfaceNumber =
862 		    serial->interface->cur_altsetting->desc.bInterfaceNumber;
863 
864 		usb_set_serial_port_data(serial->port[i], port_priv);
865 	}
866 
867 	return 0;
868 }
869 
870 static void cp210x_release(struct usb_serial *serial)
871 {
872 	struct cp210x_port_private *port_priv;
873 	int i;
874 
875 	for (i = 0; i < serial->num_ports; i++) {
876 		port_priv = usb_get_serial_port_data(serial->port[i]);
877 		kfree(port_priv);
878 		usb_set_serial_port_data(serial->port[i], NULL);
879 	}
880 }
881 
882 module_usb_serial_driver(serial_drivers, id_table);
883 
884 MODULE_DESCRIPTION(DRIVER_DESC);
885 MODULE_VERSION(DRIVER_VERSION);
886 MODULE_LICENSE("GPL");
887 
888 module_param(debug, bool, S_IRUGO | S_IWUSR);
889 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
890