xref: /linux/drivers/usb/serial/cp210x.c (revision f98a7aa81eeeadcad25665c3501c236d531d4382)
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 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
28 
29 /*
30  * Function Prototypes
31  */
32 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
33 static void cp210x_close(struct usb_serial_port *);
34 static void cp210x_get_termios(struct tty_struct *, struct usb_serial_port *);
35 static void cp210x_get_termios_port(struct usb_serial_port *port,
36 	unsigned int *cflagp, unsigned int *baudp);
37 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
38 							struct ktermios *);
39 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
40 							struct ktermios*);
41 static int cp210x_tiocmget(struct tty_struct *);
42 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
43 static int cp210x_tiocmset_port(struct usb_serial_port *port,
44 		unsigned int, unsigned int);
45 static void cp210x_break_ctl(struct tty_struct *, int);
46 static int cp210x_startup(struct usb_serial *);
47 static void cp210x_release(struct usb_serial *);
48 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
49 
50 static const struct usb_device_id id_table[] = {
51 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
52 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
53 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
54 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
55 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
56 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
57 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
58 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
59 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
60 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
61 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
62 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
63 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
64 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
65 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
66 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
67 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
68 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
69 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
70 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
71 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
72 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
73 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
74 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
75 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
76 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
77 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
78 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
79 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
80 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
81 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
82 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
83 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
84 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
85 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
86 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
87 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
88 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
89 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
90 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
91 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
92 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
93 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
94 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
95 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
96 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
97 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
98 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
99 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
100 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
101 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
102 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
103 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
104 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
105 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
106 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
107 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
108 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
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, 0x85F8) }, /* Virtenio Preon32 */
122 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
123 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
124 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
125 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
126 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
127 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
128 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
129 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
130 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
131 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
132 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
133 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
134 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
135 	{ USB_DEVICE(0x10C4, 0xEA80) }, /* Silicon Labs factory default */
136 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
137 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
138 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
139 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
140 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
141 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
142 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
143 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
144 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
145 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
146 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
147 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
148 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
149 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
150 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
151 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
152 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
153 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
154 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
155 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
156 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
157 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
158 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
159 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
160 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
161 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
162 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
163 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
164 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
165 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
166 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
167 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
168 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
169 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
170 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
171 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
172 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
173 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
174 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
175 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
176 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
177 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
178 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
179 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
180 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
181 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
182 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
183 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
184 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
185 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
186 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
187 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
188 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
189 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
190 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
191 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
192 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
193 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
194 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
195 	{ } /* Terminating Entry */
196 };
197 
198 MODULE_DEVICE_TABLE(usb, id_table);
199 
200 struct cp210x_serial_private {
201 	__u8			bInterfaceNumber;
202 };
203 
204 static struct usb_serial_driver cp210x_device = {
205 	.driver = {
206 		.owner =	THIS_MODULE,
207 		.name =		"cp210x",
208 	},
209 	.id_table		= id_table,
210 	.num_ports		= 1,
211 	.bulk_in_size		= 256,
212 	.bulk_out_size		= 256,
213 	.open			= cp210x_open,
214 	.close			= cp210x_close,
215 	.break_ctl		= cp210x_break_ctl,
216 	.set_termios		= cp210x_set_termios,
217 	.tiocmget		= cp210x_tiocmget,
218 	.tiocmset		= cp210x_tiocmset,
219 	.attach			= cp210x_startup,
220 	.release		= cp210x_release,
221 	.dtr_rts		= cp210x_dtr_rts
222 };
223 
224 static struct usb_serial_driver * const serial_drivers[] = {
225 	&cp210x_device, NULL
226 };
227 
228 /* Config request types */
229 #define REQTYPE_HOST_TO_INTERFACE	0x41
230 #define REQTYPE_INTERFACE_TO_HOST	0xc1
231 #define REQTYPE_HOST_TO_DEVICE	0x40
232 #define REQTYPE_DEVICE_TO_HOST	0xc0
233 
234 /* Config request codes */
235 #define CP210X_IFC_ENABLE	0x00
236 #define CP210X_SET_BAUDDIV	0x01
237 #define CP210X_GET_BAUDDIV	0x02
238 #define CP210X_SET_LINE_CTL	0x03
239 #define CP210X_GET_LINE_CTL	0x04
240 #define CP210X_SET_BREAK	0x05
241 #define CP210X_IMM_CHAR		0x06
242 #define CP210X_SET_MHS		0x07
243 #define CP210X_GET_MDMSTS	0x08
244 #define CP210X_SET_XON		0x09
245 #define CP210X_SET_XOFF		0x0A
246 #define CP210X_SET_EVENTMASK	0x0B
247 #define CP210X_GET_EVENTMASK	0x0C
248 #define CP210X_SET_CHAR		0x0D
249 #define CP210X_GET_CHARS	0x0E
250 #define CP210X_GET_PROPS	0x0F
251 #define CP210X_GET_COMM_STATUS	0x10
252 #define CP210X_RESET		0x11
253 #define CP210X_PURGE		0x12
254 #define CP210X_SET_FLOW		0x13
255 #define CP210X_GET_FLOW		0x14
256 #define CP210X_EMBED_EVENTS	0x15
257 #define CP210X_GET_EVENTSTATE	0x16
258 #define CP210X_SET_CHARS	0x19
259 #define CP210X_GET_BAUDRATE	0x1D
260 #define CP210X_SET_BAUDRATE	0x1E
261 
262 /* CP210X_IFC_ENABLE */
263 #define UART_ENABLE		0x0001
264 #define UART_DISABLE		0x0000
265 
266 /* CP210X_(SET|GET)_BAUDDIV */
267 #define BAUD_RATE_GEN_FREQ	0x384000
268 
269 /* CP210X_(SET|GET)_LINE_CTL */
270 #define BITS_DATA_MASK		0X0f00
271 #define BITS_DATA_5		0X0500
272 #define BITS_DATA_6		0X0600
273 #define BITS_DATA_7		0X0700
274 #define BITS_DATA_8		0X0800
275 #define BITS_DATA_9		0X0900
276 
277 #define BITS_PARITY_MASK	0x00f0
278 #define BITS_PARITY_NONE	0x0000
279 #define BITS_PARITY_ODD		0x0010
280 #define BITS_PARITY_EVEN	0x0020
281 #define BITS_PARITY_MARK	0x0030
282 #define BITS_PARITY_SPACE	0x0040
283 
284 #define BITS_STOP_MASK		0x000f
285 #define BITS_STOP_1		0x0000
286 #define BITS_STOP_1_5		0x0001
287 #define BITS_STOP_2		0x0002
288 
289 /* CP210X_SET_BREAK */
290 #define BREAK_ON		0x0001
291 #define BREAK_OFF		0x0000
292 
293 /* CP210X_(SET_MHS|GET_MDMSTS) */
294 #define CONTROL_DTR		0x0001
295 #define CONTROL_RTS		0x0002
296 #define CONTROL_CTS		0x0010
297 #define CONTROL_DSR		0x0020
298 #define CONTROL_RING		0x0040
299 #define CONTROL_DCD		0x0080
300 #define CONTROL_WRITE_DTR	0x0100
301 #define CONTROL_WRITE_RTS	0x0200
302 
303 /*
304  * cp210x_get_config
305  * Reads from the CP210x configuration registers
306  * 'size' is specified in bytes.
307  * 'data' is a pointer to a pre-allocated array of integers large
308  * enough to hold 'size' bytes (with 4 bytes to each integer)
309  */
310 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
311 		unsigned int *data, int size)
312 {
313 	struct usb_serial *serial = port->serial;
314 	struct cp210x_serial_private *spriv = usb_get_serial_data(serial);
315 	__le32 *buf;
316 	int result, i, length;
317 
318 	/* Number of integers required to contain the array */
319 	length = (((size - 1) | 3) + 1) / 4;
320 
321 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
322 	if (!buf)
323 		return -ENOMEM;
324 
325 	/* Issue the request, attempting to read 'size' bytes */
326 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
327 				request, REQTYPE_INTERFACE_TO_HOST, 0x0000,
328 				spriv->bInterfaceNumber, buf, size,
329 				USB_CTRL_GET_TIMEOUT);
330 
331 	/* Convert data into an array of integers */
332 	for (i = 0; i < length; i++)
333 		data[i] = le32_to_cpu(buf[i]);
334 
335 	kfree(buf);
336 
337 	if (result != size) {
338 		dev_dbg(&port->dev, "%s - Unable to send config request, request=0x%x size=%d result=%d\n",
339 			__func__, request, size, result);
340 		if (result > 0)
341 			result = -EPROTO;
342 
343 		return result;
344 	}
345 
346 	return 0;
347 }
348 
349 /*
350  * cp210x_set_config
351  * Writes to the CP210x configuration registers
352  * Values less than 16 bits wide are sent directly
353  * 'size' is specified in bytes.
354  */
355 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
356 		unsigned int *data, int size)
357 {
358 	struct usb_serial *serial = port->serial;
359 	struct cp210x_serial_private *spriv = usb_get_serial_data(serial);
360 	__le32 *buf;
361 	int result, i, length;
362 
363 	/* Number of integers required to contain the array */
364 	length = (((size - 1) | 3) + 1) / 4;
365 
366 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
367 	if (!buf)
368 		return -ENOMEM;
369 
370 	/* Array of integers into bytes */
371 	for (i = 0; i < length; i++)
372 		buf[i] = cpu_to_le32(data[i]);
373 
374 	if (size > 2) {
375 		result = usb_control_msg(serial->dev,
376 				usb_sndctrlpipe(serial->dev, 0),
377 				request, REQTYPE_HOST_TO_INTERFACE, 0x0000,
378 				spriv->bInterfaceNumber, buf, size,
379 				USB_CTRL_SET_TIMEOUT);
380 	} else {
381 		result = usb_control_msg(serial->dev,
382 				usb_sndctrlpipe(serial->dev, 0),
383 				request, REQTYPE_HOST_TO_INTERFACE, data[0],
384 				spriv->bInterfaceNumber, NULL, 0,
385 				USB_CTRL_SET_TIMEOUT);
386 	}
387 
388 	kfree(buf);
389 
390 	if ((size > 2 && result != size) || result < 0) {
391 		dev_dbg(&port->dev, "%s - Unable to send request, request=0x%x size=%d result=%d\n",
392 			__func__, request, size, result);
393 		if (result > 0)
394 			result = -EPROTO;
395 
396 		return result;
397 	}
398 
399 	return 0;
400 }
401 
402 /*
403  * cp210x_set_config_single
404  * Convenience function for calling cp210x_set_config on single data values
405  * without requiring an integer pointer
406  */
407 static inline int cp210x_set_config_single(struct usb_serial_port *port,
408 		u8 request, unsigned int data)
409 {
410 	return cp210x_set_config(port, request, &data, 2);
411 }
412 
413 /*
414  * cp210x_quantise_baudrate
415  * Quantises the baud rate as per AN205 Table 1
416  */
417 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
418 {
419 	if (baud <= 300)
420 		baud = 300;
421 	else if (baud <= 600)      baud = 600;
422 	else if (baud <= 1200)     baud = 1200;
423 	else if (baud <= 1800)     baud = 1800;
424 	else if (baud <= 2400)     baud = 2400;
425 	else if (baud <= 4000)     baud = 4000;
426 	else if (baud <= 4803)     baud = 4800;
427 	else if (baud <= 7207)     baud = 7200;
428 	else if (baud <= 9612)     baud = 9600;
429 	else if (baud <= 14428)    baud = 14400;
430 	else if (baud <= 16062)    baud = 16000;
431 	else if (baud <= 19250)    baud = 19200;
432 	else if (baud <= 28912)    baud = 28800;
433 	else if (baud <= 38601)    baud = 38400;
434 	else if (baud <= 51558)    baud = 51200;
435 	else if (baud <= 56280)    baud = 56000;
436 	else if (baud <= 58053)    baud = 57600;
437 	else if (baud <= 64111)    baud = 64000;
438 	else if (baud <= 77608)    baud = 76800;
439 	else if (baud <= 117028)   baud = 115200;
440 	else if (baud <= 129347)   baud = 128000;
441 	else if (baud <= 156868)   baud = 153600;
442 	else if (baud <= 237832)   baud = 230400;
443 	else if (baud <= 254234)   baud = 250000;
444 	else if (baud <= 273066)   baud = 256000;
445 	else if (baud <= 491520)   baud = 460800;
446 	else if (baud <= 567138)   baud = 500000;
447 	else if (baud <= 670254)   baud = 576000;
448 	else if (baud < 1000000)
449 		baud = 921600;
450 	else if (baud > 2000000)
451 		baud = 2000000;
452 	return baud;
453 }
454 
455 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
456 {
457 	int result;
458 
459 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
460 								UART_ENABLE);
461 	if (result) {
462 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
463 		return result;
464 	}
465 
466 	/* Configure the termios structure */
467 	cp210x_get_termios(tty, port);
468 
469 	/* The baud rate must be initialised on cp2104 */
470 	if (tty)
471 		cp210x_change_speed(tty, port, NULL);
472 
473 	return usb_serial_generic_open(tty, port);
474 }
475 
476 static void cp210x_close(struct usb_serial_port *port)
477 {
478 	usb_serial_generic_close(port);
479 	cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
480 }
481 
482 /*
483  * cp210x_get_termios
484  * Reads the baud rate, data bits, parity, stop bits and flow control mode
485  * from the device, corrects any unsupported values, and configures the
486  * termios structure to reflect the state of the device
487  */
488 static void cp210x_get_termios(struct tty_struct *tty,
489 	struct usb_serial_port *port)
490 {
491 	unsigned int baud;
492 
493 	if (tty) {
494 		cp210x_get_termios_port(tty->driver_data,
495 			&tty->termios.c_cflag, &baud);
496 		tty_encode_baud_rate(tty, baud, baud);
497 	} else {
498 		unsigned int cflag;
499 		cflag = 0;
500 		cp210x_get_termios_port(port, &cflag, &baud);
501 	}
502 }
503 
504 /*
505  * cp210x_get_termios_port
506  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
507  */
508 static void cp210x_get_termios_port(struct usb_serial_port *port,
509 	unsigned int *cflagp, unsigned int *baudp)
510 {
511 	struct device *dev = &port->dev;
512 	unsigned int cflag, modem_ctl[4];
513 	unsigned int baud;
514 	unsigned int bits;
515 
516 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
517 
518 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
519 	*baudp = baud;
520 
521 	cflag = *cflagp;
522 
523 	cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
524 	cflag &= ~CSIZE;
525 	switch (bits & BITS_DATA_MASK) {
526 	case BITS_DATA_5:
527 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
528 		cflag |= CS5;
529 		break;
530 	case BITS_DATA_6:
531 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
532 		cflag |= CS6;
533 		break;
534 	case BITS_DATA_7:
535 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
536 		cflag |= CS7;
537 		break;
538 	case BITS_DATA_8:
539 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
540 		cflag |= CS8;
541 		break;
542 	case BITS_DATA_9:
543 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
544 		cflag |= CS8;
545 		bits &= ~BITS_DATA_MASK;
546 		bits |= BITS_DATA_8;
547 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
548 		break;
549 	default:
550 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
551 		cflag |= CS8;
552 		bits &= ~BITS_DATA_MASK;
553 		bits |= BITS_DATA_8;
554 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
555 		break;
556 	}
557 
558 	switch (bits & BITS_PARITY_MASK) {
559 	case BITS_PARITY_NONE:
560 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
561 		cflag &= ~PARENB;
562 		break;
563 	case BITS_PARITY_ODD:
564 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
565 		cflag |= (PARENB|PARODD);
566 		break;
567 	case BITS_PARITY_EVEN:
568 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
569 		cflag &= ~PARODD;
570 		cflag |= PARENB;
571 		break;
572 	case BITS_PARITY_MARK:
573 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
574 		cflag |= (PARENB|PARODD|CMSPAR);
575 		break;
576 	case BITS_PARITY_SPACE:
577 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
578 		cflag &= ~PARODD;
579 		cflag |= (PARENB|CMSPAR);
580 		break;
581 	default:
582 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
583 		cflag &= ~PARENB;
584 		bits &= ~BITS_PARITY_MASK;
585 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
586 		break;
587 	}
588 
589 	cflag &= ~CSTOPB;
590 	switch (bits & BITS_STOP_MASK) {
591 	case BITS_STOP_1:
592 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
593 		break;
594 	case BITS_STOP_1_5:
595 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
596 		bits &= ~BITS_STOP_MASK;
597 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
598 		break;
599 	case BITS_STOP_2:
600 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
601 		cflag |= CSTOPB;
602 		break;
603 	default:
604 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
605 		bits &= ~BITS_STOP_MASK;
606 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
607 		break;
608 	}
609 
610 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
611 	if (modem_ctl[0] & 0x0008) {
612 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
613 		cflag |= CRTSCTS;
614 	} else {
615 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
616 		cflag &= ~CRTSCTS;
617 	}
618 
619 	*cflagp = cflag;
620 }
621 
622 /*
623  * CP2101 supports the following baud rates:
624  *
625  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
626  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
627  *
628  * CP2102 and CP2103 support the following additional rates:
629  *
630  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
631  *	576000
632  *
633  * The device will map a requested rate to a supported one, but the result
634  * of requests for rates greater than 1053257 is undefined (see AN205).
635  *
636  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
637  * respectively, with an error less than 1%. The actual rates are determined
638  * by
639  *
640  *	div = round(freq / (2 x prescale x request))
641  *	actual = freq / (2 x prescale x div)
642  *
643  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
644  * or 1 otherwise.
645  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
646  * otherwise.
647  */
648 static void cp210x_change_speed(struct tty_struct *tty,
649 		struct usb_serial_port *port, struct ktermios *old_termios)
650 {
651 	u32 baud;
652 
653 	baud = tty->termios.c_ospeed;
654 
655 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
656 	 * or to an arbitrary rate in [1M,2M].
657 	 *
658 	 * NOTE: B0 is not implemented.
659 	 */
660 	baud = cp210x_quantise_baudrate(baud);
661 
662 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
663 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
664 							sizeof(baud))) {
665 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
666 		if (old_termios)
667 			baud = old_termios->c_ospeed;
668 		else
669 			baud = 9600;
670 	}
671 
672 	tty_encode_baud_rate(tty, baud, baud);
673 }
674 
675 static void cp210x_set_termios(struct tty_struct *tty,
676 		struct usb_serial_port *port, struct ktermios *old_termios)
677 {
678 	struct device *dev = &port->dev;
679 	unsigned int cflag, old_cflag;
680 	unsigned int bits;
681 	unsigned int modem_ctl[4];
682 
683 	cflag = tty->termios.c_cflag;
684 	old_cflag = old_termios->c_cflag;
685 
686 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
687 		cp210x_change_speed(tty, port, old_termios);
688 
689 	/* If the number of data bits is to be updated */
690 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
691 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
692 		bits &= ~BITS_DATA_MASK;
693 		switch (cflag & CSIZE) {
694 		case CS5:
695 			bits |= BITS_DATA_5;
696 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
697 			break;
698 		case CS6:
699 			bits |= BITS_DATA_6;
700 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
701 			break;
702 		case CS7:
703 			bits |= BITS_DATA_7;
704 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
705 			break;
706 		case CS8:
707 			bits |= BITS_DATA_8;
708 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
709 			break;
710 		/*case CS9:
711 			bits |= BITS_DATA_9;
712 			dev_dbg(dev, "%s - data bits = 9\n", __func__);
713 			break;*/
714 		default:
715 			dev_dbg(dev, "cp210x driver does not support the number of bits requested, using 8 bit mode\n");
716 			bits |= BITS_DATA_8;
717 			break;
718 		}
719 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
720 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
721 	}
722 
723 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
724 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
725 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
726 		bits &= ~BITS_PARITY_MASK;
727 		if (cflag & PARENB) {
728 			if (cflag & CMSPAR) {
729 				if (cflag & PARODD) {
730 					bits |= BITS_PARITY_MARK;
731 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
732 				} else {
733 					bits |= BITS_PARITY_SPACE;
734 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
735 				}
736 			} else {
737 				if (cflag & PARODD) {
738 					bits |= BITS_PARITY_ODD;
739 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
740 				} else {
741 					bits |= BITS_PARITY_EVEN;
742 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
743 				}
744 			}
745 		}
746 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
747 			dev_dbg(dev, "Parity mode not supported by device\n");
748 	}
749 
750 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
751 		cp210x_get_config(port, CP210X_GET_LINE_CTL, &bits, 2);
752 		bits &= ~BITS_STOP_MASK;
753 		if (cflag & CSTOPB) {
754 			bits |= BITS_STOP_2;
755 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
756 		} else {
757 			bits |= BITS_STOP_1;
758 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
759 		}
760 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
761 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
762 	}
763 
764 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
765 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
766 		dev_dbg(dev, "%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
767 			__func__, modem_ctl[0], modem_ctl[1],
768 			modem_ctl[2], modem_ctl[3]);
769 
770 		if (cflag & CRTSCTS) {
771 			modem_ctl[0] &= ~0x7B;
772 			modem_ctl[0] |= 0x09;
773 			modem_ctl[1] = 0x80;
774 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
775 		} else {
776 			modem_ctl[0] &= ~0x7B;
777 			modem_ctl[0] |= 0x01;
778 			modem_ctl[1] |= 0x40;
779 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
780 		}
781 
782 		dev_dbg(dev, "%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
783 			__func__, modem_ctl[0], modem_ctl[1],
784 			modem_ctl[2], modem_ctl[3]);
785 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
786 	}
787 
788 }
789 
790 static int cp210x_tiocmset(struct tty_struct *tty,
791 		unsigned int set, unsigned int clear)
792 {
793 	struct usb_serial_port *port = tty->driver_data;
794 	return cp210x_tiocmset_port(port, set, clear);
795 }
796 
797 static int cp210x_tiocmset_port(struct usb_serial_port *port,
798 		unsigned int set, unsigned int clear)
799 {
800 	unsigned int control = 0;
801 
802 	if (set & TIOCM_RTS) {
803 		control |= CONTROL_RTS;
804 		control |= CONTROL_WRITE_RTS;
805 	}
806 	if (set & TIOCM_DTR) {
807 		control |= CONTROL_DTR;
808 		control |= CONTROL_WRITE_DTR;
809 	}
810 	if (clear & TIOCM_RTS) {
811 		control &= ~CONTROL_RTS;
812 		control |= CONTROL_WRITE_RTS;
813 	}
814 	if (clear & TIOCM_DTR) {
815 		control &= ~CONTROL_DTR;
816 		control |= CONTROL_WRITE_DTR;
817 	}
818 
819 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
820 
821 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
822 }
823 
824 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
825 {
826 	if (on)
827 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
828 	else
829 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
830 }
831 
832 static int cp210x_tiocmget(struct tty_struct *tty)
833 {
834 	struct usb_serial_port *port = tty->driver_data;
835 	unsigned int control;
836 	int result;
837 
838 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
839 
840 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
841 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
842 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
843 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
844 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
845 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
846 
847 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
848 
849 	return result;
850 }
851 
852 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
853 {
854 	struct usb_serial_port *port = tty->driver_data;
855 	unsigned int state;
856 
857 	if (break_state == 0)
858 		state = BREAK_OFF;
859 	else
860 		state = BREAK_ON;
861 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
862 		state == BREAK_OFF ? "off" : "on");
863 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
864 }
865 
866 static int cp210x_startup(struct usb_serial *serial)
867 {
868 	struct usb_host_interface *cur_altsetting;
869 	struct cp210x_serial_private *spriv;
870 
871 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
872 	if (!spriv)
873 		return -ENOMEM;
874 
875 	cur_altsetting = serial->interface->cur_altsetting;
876 	spriv->bInterfaceNumber = cur_altsetting->desc.bInterfaceNumber;
877 
878 	usb_set_serial_data(serial, spriv);
879 
880 	return 0;
881 }
882 
883 static void cp210x_release(struct usb_serial *serial)
884 {
885 	struct cp210x_serial_private *spriv;
886 
887 	spriv = usb_get_serial_data(serial);
888 	kfree(spriv);
889 }
890 
891 module_usb_serial_driver(serial_drivers, id_table);
892 
893 MODULE_DESCRIPTION(DRIVER_DESC);
894 MODULE_LICENSE("GPL");
895