xref: /linux/drivers/usb/serial/cp210x.c (revision 6627ae19385283b89356a199d7f03c75ba35fb29)
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 bool cp210x_tx_empty(struct usb_serial_port *port);
42 static int cp210x_tiocmget(struct tty_struct *);
43 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
44 static int cp210x_tiocmset_port(struct usb_serial_port *port,
45 		unsigned int, unsigned int);
46 static void cp210x_break_ctl(struct tty_struct *, int);
47 static int cp210x_port_probe(struct usb_serial_port *);
48 static int cp210x_port_remove(struct usb_serial_port *);
49 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
50 
51 static const struct usb_device_id id_table[] = {
52 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
53 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
54 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
55 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
56 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
57 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
58 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
59 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
60 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
61 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
62 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
63 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
64 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
65 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
66 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
67 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
68 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
69 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
70 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
71 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
72 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
73 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
74 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
75 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
76 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
77 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
78 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
79 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
80 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
81 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
82 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
83 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
84 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
85 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
86 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
87 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
88 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
89 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
90 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
91 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
92 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
93 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
94 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
95 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
96 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
97 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
98 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
99 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
100 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
101 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
102 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
103 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
104 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
105 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
106 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
107 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
108 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
109 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
110 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
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, 0x85F8) }, /* Virtenio Preon32 */
124 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
125 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
126 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
127 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
128 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
129 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
130 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
131 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
132 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
133 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
134 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
135 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
136 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
137 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
138 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
139 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
140 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
141 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
142 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
143 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
144 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
145 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
146 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
147 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
148 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
149 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
150 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
151 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
152 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
153 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
154 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
155 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
156 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
157 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
158 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
159 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
160 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
161 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
162 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
163 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
164 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
165 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
166 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
167 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
168 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
169 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
170 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
171 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
172 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
173 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
174 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
175 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
176 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
177 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
178 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
179 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
180 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
181 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
182 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
183 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
184 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
185 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
186 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
187 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
188 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
189 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
190 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
191 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
192 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
193 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
194 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
195 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
196 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
197 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
198 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
199 	{ } /* Terminating Entry */
200 };
201 
202 MODULE_DEVICE_TABLE(usb, id_table);
203 
204 struct cp210x_port_private {
205 	__u8			bInterfaceNumber;
206 	bool			has_swapped_line_ctl;
207 };
208 
209 static struct usb_serial_driver cp210x_device = {
210 	.driver = {
211 		.owner =	THIS_MODULE,
212 		.name =		"cp210x",
213 	},
214 	.id_table		= id_table,
215 	.num_ports		= 1,
216 	.bulk_in_size		= 256,
217 	.bulk_out_size		= 256,
218 	.open			= cp210x_open,
219 	.close			= cp210x_close,
220 	.break_ctl		= cp210x_break_ctl,
221 	.set_termios		= cp210x_set_termios,
222 	.tx_empty		= cp210x_tx_empty,
223 	.tiocmget		= cp210x_tiocmget,
224 	.tiocmset		= cp210x_tiocmset,
225 	.port_probe		= cp210x_port_probe,
226 	.port_remove		= cp210x_port_remove,
227 	.dtr_rts		= cp210x_dtr_rts
228 };
229 
230 static struct usb_serial_driver * const serial_drivers[] = {
231 	&cp210x_device, NULL
232 };
233 
234 /* Config request types */
235 #define REQTYPE_HOST_TO_INTERFACE	0x41
236 #define REQTYPE_INTERFACE_TO_HOST	0xc1
237 #define REQTYPE_HOST_TO_DEVICE	0x40
238 #define REQTYPE_DEVICE_TO_HOST	0xc0
239 
240 /* Config request codes */
241 #define CP210X_IFC_ENABLE	0x00
242 #define CP210X_SET_BAUDDIV	0x01
243 #define CP210X_GET_BAUDDIV	0x02
244 #define CP210X_SET_LINE_CTL	0x03
245 #define CP210X_GET_LINE_CTL	0x04
246 #define CP210X_SET_BREAK	0x05
247 #define CP210X_IMM_CHAR		0x06
248 #define CP210X_SET_MHS		0x07
249 #define CP210X_GET_MDMSTS	0x08
250 #define CP210X_SET_XON		0x09
251 #define CP210X_SET_XOFF		0x0A
252 #define CP210X_SET_EVENTMASK	0x0B
253 #define CP210X_GET_EVENTMASK	0x0C
254 #define CP210X_SET_CHAR		0x0D
255 #define CP210X_GET_CHARS	0x0E
256 #define CP210X_GET_PROPS	0x0F
257 #define CP210X_GET_COMM_STATUS	0x10
258 #define CP210X_RESET		0x11
259 #define CP210X_PURGE		0x12
260 #define CP210X_SET_FLOW		0x13
261 #define CP210X_GET_FLOW		0x14
262 #define CP210X_EMBED_EVENTS	0x15
263 #define CP210X_GET_EVENTSTATE	0x16
264 #define CP210X_SET_CHARS	0x19
265 #define CP210X_GET_BAUDRATE	0x1D
266 #define CP210X_SET_BAUDRATE	0x1E
267 
268 /* CP210X_IFC_ENABLE */
269 #define UART_ENABLE		0x0001
270 #define UART_DISABLE		0x0000
271 
272 /* CP210X_(SET|GET)_BAUDDIV */
273 #define BAUD_RATE_GEN_FREQ	0x384000
274 
275 /* CP210X_(SET|GET)_LINE_CTL */
276 #define BITS_DATA_MASK		0X0f00
277 #define BITS_DATA_5		0X0500
278 #define BITS_DATA_6		0X0600
279 #define BITS_DATA_7		0X0700
280 #define BITS_DATA_8		0X0800
281 #define BITS_DATA_9		0X0900
282 
283 #define BITS_PARITY_MASK	0x00f0
284 #define BITS_PARITY_NONE	0x0000
285 #define BITS_PARITY_ODD		0x0010
286 #define BITS_PARITY_EVEN	0x0020
287 #define BITS_PARITY_MARK	0x0030
288 #define BITS_PARITY_SPACE	0x0040
289 
290 #define BITS_STOP_MASK		0x000f
291 #define BITS_STOP_1		0x0000
292 #define BITS_STOP_1_5		0x0001
293 #define BITS_STOP_2		0x0002
294 
295 /* CP210X_SET_BREAK */
296 #define BREAK_ON		0x0001
297 #define BREAK_OFF		0x0000
298 
299 /* CP210X_(SET_MHS|GET_MDMSTS) */
300 #define CONTROL_DTR		0x0001
301 #define CONTROL_RTS		0x0002
302 #define CONTROL_CTS		0x0010
303 #define CONTROL_DSR		0x0020
304 #define CONTROL_RING		0x0040
305 #define CONTROL_DCD		0x0080
306 #define CONTROL_WRITE_DTR	0x0100
307 #define CONTROL_WRITE_RTS	0x0200
308 
309 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
310 struct cp210x_comm_status {
311 	__le32   ulErrors;
312 	__le32   ulHoldReasons;
313 	__le32   ulAmountInInQueue;
314 	__le32   ulAmountInOutQueue;
315 	u8       bEofReceived;
316 	u8       bWaitForImmediate;
317 	u8       bReserved;
318 } __packed;
319 
320 /*
321  * CP210X_PURGE - 16 bits passed in wValue of USB request.
322  * SiLabs app note AN571 gives a strange description of the 4 bits:
323  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
324  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
325  */
326 #define PURGE_ALL		0x000f
327 
328 /*
329  * cp210x_get_config
330  * Reads from the CP210x configuration registers
331  * 'size' is specified in bytes.
332  * 'data' is a pointer to a pre-allocated array of integers large
333  * enough to hold 'size' bytes (with 4 bytes to each integer)
334  */
335 static int cp210x_get_config(struct usb_serial_port *port, u8 request,
336 		unsigned int *data, int size)
337 {
338 	struct usb_serial *serial = port->serial;
339 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
340 	__le32 *buf;
341 	int result, i, length;
342 
343 	/* Number of integers required to contain the array */
344 	length = (((size - 1) | 3) + 1) / 4;
345 
346 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
347 	if (!buf)
348 		return -ENOMEM;
349 
350 	/* Issue the request, attempting to read 'size' bytes */
351 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
352 				request, REQTYPE_INTERFACE_TO_HOST, 0x0000,
353 				port_priv->bInterfaceNumber, buf, size,
354 				USB_CTRL_GET_TIMEOUT);
355 
356 	/* Convert data into an array of integers */
357 	for (i = 0; i < length; i++)
358 		data[i] = le32_to_cpu(buf[i]);
359 
360 	kfree(buf);
361 
362 	if (result != size) {
363 		dev_dbg(&port->dev, "%s - Unable to send config 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
376  * Writes to the CP210x configuration registers
377  * Values less than 16 bits wide are sent directly
378  * 'size' is specified in bytes.
379  */
380 static int cp210x_set_config(struct usb_serial_port *port, u8 request,
381 		unsigned int *data, int size)
382 {
383 	struct usb_serial *serial = port->serial;
384 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
385 	__le32 *buf;
386 	int result, i, length;
387 
388 	/* Number of integers required to contain the array */
389 	length = (((size - 1) | 3) + 1) / 4;
390 
391 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
392 	if (!buf)
393 		return -ENOMEM;
394 
395 	/* Array of integers into bytes */
396 	for (i = 0; i < length; i++)
397 		buf[i] = cpu_to_le32(data[i]);
398 
399 	if (size > 2) {
400 		result = usb_control_msg(serial->dev,
401 				usb_sndctrlpipe(serial->dev, 0),
402 				request, REQTYPE_HOST_TO_INTERFACE, 0x0000,
403 				port_priv->bInterfaceNumber, buf, size,
404 				USB_CTRL_SET_TIMEOUT);
405 	} else {
406 		result = usb_control_msg(serial->dev,
407 				usb_sndctrlpipe(serial->dev, 0),
408 				request, REQTYPE_HOST_TO_INTERFACE, data[0],
409 				port_priv->bInterfaceNumber, NULL, 0,
410 				USB_CTRL_SET_TIMEOUT);
411 	}
412 
413 	kfree(buf);
414 
415 	if ((size > 2 && result != size) || result < 0) {
416 		dev_dbg(&port->dev, "%s - Unable to send request, request=0x%x size=%d result=%d\n",
417 			__func__, request, size, result);
418 		if (result > 0)
419 			result = -EPROTO;
420 
421 		return result;
422 	}
423 
424 	return 0;
425 }
426 
427 /*
428  * cp210x_set_config_single
429  * Convenience function for calling cp210x_set_config on single data values
430  * without requiring an integer pointer
431  */
432 static inline int cp210x_set_config_single(struct usb_serial_port *port,
433 		u8 request, unsigned int data)
434 {
435 	return cp210x_set_config(port, request, &data, 2);
436 }
437 
438 /*
439  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
440  * Write a known good value 0x800, read it back.
441  * If it comes back swapped the bug is detected.
442  * Preserve the original register value.
443  */
444 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
445 {
446 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
447 	unsigned int line_ctl_save;
448 	unsigned int line_ctl_test;
449 	int err;
450 
451 	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, &line_ctl_save, 2);
452 	if (err)
453 		return err;
454 
455 	line_ctl_test = 0x800;
456 	err = cp210x_set_config(port, CP210X_SET_LINE_CTL, &line_ctl_test, 2);
457 	if (err)
458 		return err;
459 
460 	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, &line_ctl_test, 2);
461 	if (err)
462 		return err;
463 
464 	if (line_ctl_test == 8) {
465 		port_priv->has_swapped_line_ctl = true;
466 		line_ctl_save = swab16((u16)line_ctl_save);
467 	}
468 
469 	return cp210x_set_config(port, CP210X_SET_LINE_CTL, &line_ctl_save, 2);
470 }
471 
472 /*
473  * Must always be called instead of cp210x_get_config(CP210X_GET_LINE_CTL)
474  * to workaround cp2108 bug and get correct value.
475  */
476 static int cp210x_get_line_ctl(struct usb_serial_port *port, unsigned int *ctl)
477 {
478 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
479 	int err;
480 
481 	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, ctl, 2);
482 	if (err)
483 		return err;
484 
485 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
486 	if (port_priv->has_swapped_line_ctl)
487 		*ctl = swab16((u16)(*ctl));
488 
489 	return 0;
490 }
491 
492 /*
493  * cp210x_quantise_baudrate
494  * Quantises the baud rate as per AN205 Table 1
495  */
496 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
497 {
498 	if (baud <= 300)
499 		baud = 300;
500 	else if (baud <= 600)      baud = 600;
501 	else if (baud <= 1200)     baud = 1200;
502 	else if (baud <= 1800)     baud = 1800;
503 	else if (baud <= 2400)     baud = 2400;
504 	else if (baud <= 4000)     baud = 4000;
505 	else if (baud <= 4803)     baud = 4800;
506 	else if (baud <= 7207)     baud = 7200;
507 	else if (baud <= 9612)     baud = 9600;
508 	else if (baud <= 14428)    baud = 14400;
509 	else if (baud <= 16062)    baud = 16000;
510 	else if (baud <= 19250)    baud = 19200;
511 	else if (baud <= 28912)    baud = 28800;
512 	else if (baud <= 38601)    baud = 38400;
513 	else if (baud <= 51558)    baud = 51200;
514 	else if (baud <= 56280)    baud = 56000;
515 	else if (baud <= 58053)    baud = 57600;
516 	else if (baud <= 64111)    baud = 64000;
517 	else if (baud <= 77608)    baud = 76800;
518 	else if (baud <= 117028)   baud = 115200;
519 	else if (baud <= 129347)   baud = 128000;
520 	else if (baud <= 156868)   baud = 153600;
521 	else if (baud <= 237832)   baud = 230400;
522 	else if (baud <= 254234)   baud = 250000;
523 	else if (baud <= 273066)   baud = 256000;
524 	else if (baud <= 491520)   baud = 460800;
525 	else if (baud <= 567138)   baud = 500000;
526 	else if (baud <= 670254)   baud = 576000;
527 	else if (baud < 1000000)
528 		baud = 921600;
529 	else if (baud > 2000000)
530 		baud = 2000000;
531 	return baud;
532 }
533 
534 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
535 {
536 	int result;
537 
538 	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,
539 								UART_ENABLE);
540 	if (result) {
541 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
542 		return result;
543 	}
544 
545 	/* Configure the termios structure */
546 	cp210x_get_termios(tty, port);
547 
548 	/* The baud rate must be initialised on cp2104 */
549 	if (tty)
550 		cp210x_change_speed(tty, port, NULL);
551 
552 	return usb_serial_generic_open(tty, port);
553 }
554 
555 static void cp210x_close(struct usb_serial_port *port)
556 {
557 	unsigned int purge_ctl;
558 
559 	usb_serial_generic_close(port);
560 
561 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
562 	purge_ctl = PURGE_ALL;
563 	cp210x_set_config(port, CP210X_PURGE, &purge_ctl, 2);
564 
565 	cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
566 }
567 
568 /*
569  * Read how many bytes are waiting in the TX queue.
570  */
571 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
572 		u32 *count)
573 {
574 	struct usb_serial *serial = port->serial;
575 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
576 	struct cp210x_comm_status *sts;
577 	int result;
578 
579 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
580 	if (!sts)
581 		return -ENOMEM;
582 
583 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
584 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
585 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
586 			USB_CTRL_GET_TIMEOUT);
587 	if (result == sizeof(*sts)) {
588 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
589 		result = 0;
590 	} else {
591 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
592 		if (result >= 0)
593 			result = -EPROTO;
594 	}
595 
596 	kfree(sts);
597 
598 	return result;
599 }
600 
601 static bool cp210x_tx_empty(struct usb_serial_port *port)
602 {
603 	int err;
604 	u32 count;
605 
606 	err = cp210x_get_tx_queue_byte_count(port, &count);
607 	if (err)
608 		return true;
609 
610 	return !count;
611 }
612 
613 /*
614  * cp210x_get_termios
615  * Reads the baud rate, data bits, parity, stop bits and flow control mode
616  * from the device, corrects any unsupported values, and configures the
617  * termios structure to reflect the state of the device
618  */
619 static void cp210x_get_termios(struct tty_struct *tty,
620 	struct usb_serial_port *port)
621 {
622 	unsigned int baud;
623 
624 	if (tty) {
625 		cp210x_get_termios_port(tty->driver_data,
626 			&tty->termios.c_cflag, &baud);
627 		tty_encode_baud_rate(tty, baud, baud);
628 	} else {
629 		unsigned int cflag;
630 		cflag = 0;
631 		cp210x_get_termios_port(port, &cflag, &baud);
632 	}
633 }
634 
635 /*
636  * cp210x_get_termios_port
637  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
638  */
639 static void cp210x_get_termios_port(struct usb_serial_port *port,
640 	unsigned int *cflagp, unsigned int *baudp)
641 {
642 	struct device *dev = &port->dev;
643 	unsigned int cflag, modem_ctl[4];
644 	unsigned int baud;
645 	unsigned int bits;
646 
647 	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
648 
649 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
650 	*baudp = baud;
651 
652 	cflag = *cflagp;
653 
654 	cp210x_get_line_ctl(port, &bits);
655 	cflag &= ~CSIZE;
656 	switch (bits & BITS_DATA_MASK) {
657 	case BITS_DATA_5:
658 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
659 		cflag |= CS5;
660 		break;
661 	case BITS_DATA_6:
662 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
663 		cflag |= CS6;
664 		break;
665 	case BITS_DATA_7:
666 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
667 		cflag |= CS7;
668 		break;
669 	case BITS_DATA_8:
670 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
671 		cflag |= CS8;
672 		break;
673 	case BITS_DATA_9:
674 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
675 		cflag |= CS8;
676 		bits &= ~BITS_DATA_MASK;
677 		bits |= BITS_DATA_8;
678 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
679 		break;
680 	default:
681 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
682 		cflag |= CS8;
683 		bits &= ~BITS_DATA_MASK;
684 		bits |= BITS_DATA_8;
685 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
686 		break;
687 	}
688 
689 	switch (bits & BITS_PARITY_MASK) {
690 	case BITS_PARITY_NONE:
691 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
692 		cflag &= ~PARENB;
693 		break;
694 	case BITS_PARITY_ODD:
695 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
696 		cflag |= (PARENB|PARODD);
697 		break;
698 	case BITS_PARITY_EVEN:
699 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
700 		cflag &= ~PARODD;
701 		cflag |= PARENB;
702 		break;
703 	case BITS_PARITY_MARK:
704 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
705 		cflag |= (PARENB|PARODD|CMSPAR);
706 		break;
707 	case BITS_PARITY_SPACE:
708 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
709 		cflag &= ~PARODD;
710 		cflag |= (PARENB|CMSPAR);
711 		break;
712 	default:
713 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
714 		cflag &= ~PARENB;
715 		bits &= ~BITS_PARITY_MASK;
716 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
717 		break;
718 	}
719 
720 	cflag &= ~CSTOPB;
721 	switch (bits & BITS_STOP_MASK) {
722 	case BITS_STOP_1:
723 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
724 		break;
725 	case BITS_STOP_1_5:
726 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
727 		bits &= ~BITS_STOP_MASK;
728 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
729 		break;
730 	case BITS_STOP_2:
731 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
732 		cflag |= CSTOPB;
733 		break;
734 	default:
735 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
736 		bits &= ~BITS_STOP_MASK;
737 		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
738 		break;
739 	}
740 
741 	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
742 	if (modem_ctl[0] & 0x0008) {
743 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
744 		cflag |= CRTSCTS;
745 	} else {
746 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
747 		cflag &= ~CRTSCTS;
748 	}
749 
750 	*cflagp = cflag;
751 }
752 
753 /*
754  * CP2101 supports the following baud rates:
755  *
756  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
757  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
758  *
759  * CP2102 and CP2103 support the following additional rates:
760  *
761  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
762  *	576000
763  *
764  * The device will map a requested rate to a supported one, but the result
765  * of requests for rates greater than 1053257 is undefined (see AN205).
766  *
767  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
768  * respectively, with an error less than 1%. The actual rates are determined
769  * by
770  *
771  *	div = round(freq / (2 x prescale x request))
772  *	actual = freq / (2 x prescale x div)
773  *
774  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
775  * or 1 otherwise.
776  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
777  * otherwise.
778  */
779 static void cp210x_change_speed(struct tty_struct *tty,
780 		struct usb_serial_port *port, struct ktermios *old_termios)
781 {
782 	u32 baud;
783 
784 	baud = tty->termios.c_ospeed;
785 
786 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
787 	 * or to an arbitrary rate in [1M,2M].
788 	 *
789 	 * NOTE: B0 is not implemented.
790 	 */
791 	baud = cp210x_quantise_baudrate(baud);
792 
793 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
794 	if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
795 							sizeof(baud))) {
796 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
797 		if (old_termios)
798 			baud = old_termios->c_ospeed;
799 		else
800 			baud = 9600;
801 	}
802 
803 	tty_encode_baud_rate(tty, baud, baud);
804 }
805 
806 static void cp210x_set_termios(struct tty_struct *tty,
807 		struct usb_serial_port *port, struct ktermios *old_termios)
808 {
809 	struct device *dev = &port->dev;
810 	unsigned int cflag, old_cflag;
811 	unsigned int bits;
812 	unsigned int modem_ctl[4];
813 
814 	cflag = tty->termios.c_cflag;
815 	old_cflag = old_termios->c_cflag;
816 
817 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
818 		cp210x_change_speed(tty, port, old_termios);
819 
820 	/* If the number of data bits is to be updated */
821 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
822 		cp210x_get_line_ctl(port, &bits);
823 		bits &= ~BITS_DATA_MASK;
824 		switch (cflag & CSIZE) {
825 		case CS5:
826 			bits |= BITS_DATA_5;
827 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
828 			break;
829 		case CS6:
830 			bits |= BITS_DATA_6;
831 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
832 			break;
833 		case CS7:
834 			bits |= BITS_DATA_7;
835 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
836 			break;
837 		case CS8:
838 			bits |= BITS_DATA_8;
839 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
840 			break;
841 		/*case CS9:
842 			bits |= BITS_DATA_9;
843 			dev_dbg(dev, "%s - data bits = 9\n", __func__);
844 			break;*/
845 		default:
846 			dev_dbg(dev, "cp210x driver does not support the number of bits requested, using 8 bit mode\n");
847 			bits |= BITS_DATA_8;
848 			break;
849 		}
850 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
851 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
852 	}
853 
854 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
855 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
856 		cp210x_get_line_ctl(port, &bits);
857 		bits &= ~BITS_PARITY_MASK;
858 		if (cflag & PARENB) {
859 			if (cflag & CMSPAR) {
860 				if (cflag & PARODD) {
861 					bits |= BITS_PARITY_MARK;
862 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
863 				} else {
864 					bits |= BITS_PARITY_SPACE;
865 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
866 				}
867 			} else {
868 				if (cflag & PARODD) {
869 					bits |= BITS_PARITY_ODD;
870 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
871 				} else {
872 					bits |= BITS_PARITY_EVEN;
873 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
874 				}
875 			}
876 		}
877 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
878 			dev_dbg(dev, "Parity mode not supported by device\n");
879 	}
880 
881 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
882 		cp210x_get_line_ctl(port, &bits);
883 		bits &= ~BITS_STOP_MASK;
884 		if (cflag & CSTOPB) {
885 			bits |= BITS_STOP_2;
886 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
887 		} else {
888 			bits |= BITS_STOP_1;
889 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
890 		}
891 		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
892 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
893 	}
894 
895 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
896 		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);
897 		dev_dbg(dev, "%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
898 			__func__, modem_ctl[0], modem_ctl[1],
899 			modem_ctl[2], modem_ctl[3]);
900 
901 		if (cflag & CRTSCTS) {
902 			modem_ctl[0] &= ~0x7B;
903 			modem_ctl[0] |= 0x09;
904 			modem_ctl[1] = 0x80;
905 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
906 		} else {
907 			modem_ctl[0] &= ~0x7B;
908 			modem_ctl[0] |= 0x01;
909 			modem_ctl[1] |= 0x40;
910 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
911 		}
912 
913 		dev_dbg(dev, "%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",
914 			__func__, modem_ctl[0], modem_ctl[1],
915 			modem_ctl[2], modem_ctl[3]);
916 		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
917 	}
918 
919 }
920 
921 static int cp210x_tiocmset(struct tty_struct *tty,
922 		unsigned int set, unsigned int clear)
923 {
924 	struct usb_serial_port *port = tty->driver_data;
925 	return cp210x_tiocmset_port(port, set, clear);
926 }
927 
928 static int cp210x_tiocmset_port(struct usb_serial_port *port,
929 		unsigned int set, unsigned int clear)
930 {
931 	unsigned int control = 0;
932 
933 	if (set & TIOCM_RTS) {
934 		control |= CONTROL_RTS;
935 		control |= CONTROL_WRITE_RTS;
936 	}
937 	if (set & TIOCM_DTR) {
938 		control |= CONTROL_DTR;
939 		control |= CONTROL_WRITE_DTR;
940 	}
941 	if (clear & TIOCM_RTS) {
942 		control &= ~CONTROL_RTS;
943 		control |= CONTROL_WRITE_RTS;
944 	}
945 	if (clear & TIOCM_DTR) {
946 		control &= ~CONTROL_DTR;
947 		control |= CONTROL_WRITE_DTR;
948 	}
949 
950 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
951 
952 	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
953 }
954 
955 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
956 {
957 	if (on)
958 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
959 	else
960 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
961 }
962 
963 static int cp210x_tiocmget(struct tty_struct *tty)
964 {
965 	struct usb_serial_port *port = tty->driver_data;
966 	unsigned int control;
967 	int result;
968 
969 	cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
970 
971 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
972 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
973 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
974 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
975 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
976 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
977 
978 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
979 
980 	return result;
981 }
982 
983 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
984 {
985 	struct usb_serial_port *port = tty->driver_data;
986 	unsigned int state;
987 
988 	if (break_state == 0)
989 		state = BREAK_OFF;
990 	else
991 		state = BREAK_ON;
992 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
993 		state == BREAK_OFF ? "off" : "on");
994 	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
995 }
996 
997 static int cp210x_port_probe(struct usb_serial_port *port)
998 {
999 	struct usb_serial *serial = port->serial;
1000 	struct usb_host_interface *cur_altsetting;
1001 	struct cp210x_port_private *port_priv;
1002 	int ret;
1003 
1004 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1005 	if (!port_priv)
1006 		return -ENOMEM;
1007 
1008 	cur_altsetting = serial->interface->cur_altsetting;
1009 	port_priv->bInterfaceNumber = cur_altsetting->desc.bInterfaceNumber;
1010 
1011 	usb_set_serial_port_data(port, port_priv);
1012 
1013 	ret = cp210x_detect_swapped_line_ctl(port);
1014 	if (ret) {
1015 		kfree(port_priv);
1016 		return ret;
1017 	}
1018 
1019 	return 0;
1020 }
1021 
1022 static int cp210x_port_remove(struct usb_serial_port *port)
1023 {
1024 	struct cp210x_port_private *port_priv;
1025 
1026 	port_priv = usb_get_serial_port_data(port);
1027 	kfree(port_priv);
1028 
1029 	return 0;
1030 }
1031 
1032 module_usb_serial_driver(serial_drivers, id_table);
1033 
1034 MODULE_DESCRIPTION(DRIVER_DESC);
1035 MODULE_LICENSE("GPL");
1036