xref: /linux/drivers/usb/serial/cp210x.c (revision 32786fdc9506aeba98278c1844d4bfb766863832)
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 #include <linux/gpio/driver.h>
27 #include <linux/bitops.h>
28 #include <linux/mutex.h>
29 
30 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
31 
32 /*
33  * Function Prototypes
34  */
35 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
36 static void cp210x_close(struct usb_serial_port *);
37 static void cp210x_get_termios(struct tty_struct *, struct usb_serial_port *);
38 static void cp210x_get_termios_port(struct usb_serial_port *port,
39 	tcflag_t *cflagp, unsigned int *baudp);
40 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
41 							struct ktermios *);
42 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
43 							struct ktermios*);
44 static bool cp210x_tx_empty(struct usb_serial_port *port);
45 static int cp210x_tiocmget(struct tty_struct *);
46 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
47 static int cp210x_tiocmset_port(struct usb_serial_port *port,
48 		unsigned int, unsigned int);
49 static void cp210x_break_ctl(struct tty_struct *, int);
50 static int cp210x_attach(struct usb_serial *);
51 static void cp210x_disconnect(struct usb_serial *);
52 static void cp210x_release(struct usb_serial *);
53 static int cp210x_port_probe(struct usb_serial_port *);
54 static int cp210x_port_remove(struct usb_serial_port *);
55 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
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(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
64 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
65 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
66 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
67 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
68 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
69 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
71 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
72 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
73 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
74 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
75 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
76 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
77 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
78 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
79 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
80 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
81 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
82 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
83 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
84 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
85 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
86 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
87 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
88 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
89 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
90 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
91 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
92 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
93 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
94 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
95 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
96 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
97 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
98 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
99 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
100 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
101 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
102 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
103 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
104 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
105 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
106 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
107 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
108 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
109 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
110 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
111 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
112 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
113 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
114 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
115 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
116 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
117 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
118 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
119 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
120 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
121 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
122 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
123 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
124 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
125 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
126 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
127 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
128 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
129 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
130 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
131 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
132 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
133 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
134 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
135 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
136 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
137 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
138 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
139 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
140 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
141 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
142 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
143 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
144 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
145 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
146 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
147 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
148 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
149 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
150 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
151 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
152 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
153 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
154 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
155 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
156 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
157 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
158 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
159 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
160 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
161 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
162 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
163 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
164 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
165 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
166 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
167 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
168 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
169 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
170 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
171 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
172 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
173 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
174 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
175 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
176 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
177 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
178 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
179 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
180 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
181 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
182 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
183 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
184 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
185 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
186 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
187 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
188 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
189 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
190 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
191 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
192 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
193 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
194 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
195 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
196 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
197 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
198 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
199 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
200 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
201 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
202 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
203 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
204 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
205 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
206 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
207 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
208 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
209 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
210 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
211 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
212 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
213 	{ } /* Terminating Entry */
214 };
215 
216 MODULE_DEVICE_TABLE(usb, id_table);
217 
218 struct cp210x_serial_private {
219 #ifdef CONFIG_GPIOLIB
220 	struct gpio_chip	gc;
221 	u8			config;
222 	u8			gpio_mode;
223 	bool			gpio_registered;
224 #endif
225 	u8			partnum;
226 };
227 
228 struct cp210x_port_private {
229 	__u8			bInterfaceNumber;
230 	bool			has_swapped_line_ctl;
231 };
232 
233 static struct usb_serial_driver cp210x_device = {
234 	.driver = {
235 		.owner =	THIS_MODULE,
236 		.name =		"cp210x",
237 	},
238 	.id_table		= id_table,
239 	.num_ports		= 1,
240 	.bulk_in_size		= 256,
241 	.bulk_out_size		= 256,
242 	.open			= cp210x_open,
243 	.close			= cp210x_close,
244 	.break_ctl		= cp210x_break_ctl,
245 	.set_termios		= cp210x_set_termios,
246 	.tx_empty		= cp210x_tx_empty,
247 	.tiocmget		= cp210x_tiocmget,
248 	.tiocmset		= cp210x_tiocmset,
249 	.attach			= cp210x_attach,
250 	.disconnect		= cp210x_disconnect,
251 	.release		= cp210x_release,
252 	.port_probe		= cp210x_port_probe,
253 	.port_remove		= cp210x_port_remove,
254 	.dtr_rts		= cp210x_dtr_rts
255 };
256 
257 static struct usb_serial_driver * const serial_drivers[] = {
258 	&cp210x_device, NULL
259 };
260 
261 /* Config request types */
262 #define REQTYPE_HOST_TO_INTERFACE	0x41
263 #define REQTYPE_INTERFACE_TO_HOST	0xc1
264 #define REQTYPE_HOST_TO_DEVICE	0x40
265 #define REQTYPE_DEVICE_TO_HOST	0xc0
266 
267 /* Config request codes */
268 #define CP210X_IFC_ENABLE	0x00
269 #define CP210X_SET_BAUDDIV	0x01
270 #define CP210X_GET_BAUDDIV	0x02
271 #define CP210X_SET_LINE_CTL	0x03
272 #define CP210X_GET_LINE_CTL	0x04
273 #define CP210X_SET_BREAK	0x05
274 #define CP210X_IMM_CHAR		0x06
275 #define CP210X_SET_MHS		0x07
276 #define CP210X_GET_MDMSTS	0x08
277 #define CP210X_SET_XON		0x09
278 #define CP210X_SET_XOFF		0x0A
279 #define CP210X_SET_EVENTMASK	0x0B
280 #define CP210X_GET_EVENTMASK	0x0C
281 #define CP210X_SET_CHAR		0x0D
282 #define CP210X_GET_CHARS	0x0E
283 #define CP210X_GET_PROPS	0x0F
284 #define CP210X_GET_COMM_STATUS	0x10
285 #define CP210X_RESET		0x11
286 #define CP210X_PURGE		0x12
287 #define CP210X_SET_FLOW		0x13
288 #define CP210X_GET_FLOW		0x14
289 #define CP210X_EMBED_EVENTS	0x15
290 #define CP210X_GET_EVENTSTATE	0x16
291 #define CP210X_SET_CHARS	0x19
292 #define CP210X_GET_BAUDRATE	0x1D
293 #define CP210X_SET_BAUDRATE	0x1E
294 #define CP210X_VENDOR_SPECIFIC	0xFF
295 
296 /* CP210X_IFC_ENABLE */
297 #define UART_ENABLE		0x0001
298 #define UART_DISABLE		0x0000
299 
300 /* CP210X_(SET|GET)_BAUDDIV */
301 #define BAUD_RATE_GEN_FREQ	0x384000
302 
303 /* CP210X_(SET|GET)_LINE_CTL */
304 #define BITS_DATA_MASK		0X0f00
305 #define BITS_DATA_5		0X0500
306 #define BITS_DATA_6		0X0600
307 #define BITS_DATA_7		0X0700
308 #define BITS_DATA_8		0X0800
309 #define BITS_DATA_9		0X0900
310 
311 #define BITS_PARITY_MASK	0x00f0
312 #define BITS_PARITY_NONE	0x0000
313 #define BITS_PARITY_ODD		0x0010
314 #define BITS_PARITY_EVEN	0x0020
315 #define BITS_PARITY_MARK	0x0030
316 #define BITS_PARITY_SPACE	0x0040
317 
318 #define BITS_STOP_MASK		0x000f
319 #define BITS_STOP_1		0x0000
320 #define BITS_STOP_1_5		0x0001
321 #define BITS_STOP_2		0x0002
322 
323 /* CP210X_SET_BREAK */
324 #define BREAK_ON		0x0001
325 #define BREAK_OFF		0x0000
326 
327 /* CP210X_(SET_MHS|GET_MDMSTS) */
328 #define CONTROL_DTR		0x0001
329 #define CONTROL_RTS		0x0002
330 #define CONTROL_CTS		0x0010
331 #define CONTROL_DSR		0x0020
332 #define CONTROL_RING		0x0040
333 #define CONTROL_DCD		0x0080
334 #define CONTROL_WRITE_DTR	0x0100
335 #define CONTROL_WRITE_RTS	0x0200
336 
337 /* CP210X_VENDOR_SPECIFIC values */
338 #define CP210X_READ_LATCH	0x00C2
339 #define CP210X_GET_PARTNUM	0x370B
340 #define CP210X_GET_PORTCONFIG	0x370C
341 #define CP210X_GET_DEVICEMODE	0x3711
342 #define CP210X_WRITE_LATCH	0x37E1
343 
344 /* Part number definitions */
345 #define CP210X_PARTNUM_CP2101	0x01
346 #define CP210X_PARTNUM_CP2102	0x02
347 #define CP210X_PARTNUM_CP2103	0x03
348 #define CP210X_PARTNUM_CP2104	0x04
349 #define CP210X_PARTNUM_CP2105	0x05
350 #define CP210X_PARTNUM_CP2108	0x08
351 
352 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
353 struct cp210x_comm_status {
354 	__le32   ulErrors;
355 	__le32   ulHoldReasons;
356 	__le32   ulAmountInInQueue;
357 	__le32   ulAmountInOutQueue;
358 	u8       bEofReceived;
359 	u8       bWaitForImmediate;
360 	u8       bReserved;
361 } __packed;
362 
363 /*
364  * CP210X_PURGE - 16 bits passed in wValue of USB request.
365  * SiLabs app note AN571 gives a strange description of the 4 bits:
366  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
367  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
368  */
369 #define PURGE_ALL		0x000f
370 
371 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
372 struct cp210x_flow_ctl {
373 	__le32	ulControlHandshake;
374 	__le32	ulFlowReplace;
375 	__le32	ulXonLimit;
376 	__le32	ulXoffLimit;
377 } __packed;
378 
379 /* cp210x_flow_ctl::ulControlHandshake */
380 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
381 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
382 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
383 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
384 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
385 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
386 
387 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
388 #define CP210X_SERIAL_DTR_INACTIVE	0
389 #define CP210X_SERIAL_DTR_ACTIVE	1
390 #define CP210X_SERIAL_DTR_FLOW_CTL	2
391 
392 /* cp210x_flow_ctl::ulFlowReplace */
393 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
394 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
395 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
396 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
397 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
398 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
399 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
400 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
401 
402 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
403 #define CP210X_SERIAL_RTS_INACTIVE	0
404 #define CP210X_SERIAL_RTS_ACTIVE	1
405 #define CP210X_SERIAL_RTS_FLOW_CTL	2
406 
407 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
408 struct cp210x_pin_mode {
409 	u8	eci;
410 	u8	sci;
411 } __packed;
412 
413 #define CP210X_PIN_MODE_MODEM		0
414 #define CP210X_PIN_MODE_GPIO		BIT(0)
415 
416 /*
417  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes.
418  * Structure needs padding due to unused/unspecified bytes.
419  */
420 struct cp210x_config {
421 	__le16	gpio_mode;
422 	u8	__pad0[2];
423 	__le16	reset_state;
424 	u8	__pad1[4];
425 	__le16	suspend_state;
426 	u8	sci_cfg;
427 	u8	eci_cfg;
428 	u8	device_cfg;
429 } __packed;
430 
431 /* GPIO modes */
432 #define CP210X_SCI_GPIO_MODE_OFFSET	9
433 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
434 
435 #define CP210X_ECI_GPIO_MODE_OFFSET	2
436 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
437 
438 /* CP2105 port configuration values */
439 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
440 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
441 #define CP2105_GPIO1_RS485_MODE		BIT(2)
442 
443 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
444 struct cp210x_gpio_write {
445 	u8	mask;
446 	u8	state;
447 } __packed;
448 
449 /*
450  * Helper to get interface number when we only have struct usb_serial.
451  */
452 static u8 cp210x_interface_num(struct usb_serial *serial)
453 {
454 	struct usb_host_interface *cur_altsetting;
455 
456 	cur_altsetting = serial->interface->cur_altsetting;
457 
458 	return cur_altsetting->desc.bInterfaceNumber;
459 }
460 
461 /*
462  * Reads a variable-sized block of CP210X_ registers, identified by req.
463  * Returns data into buf in native USB byte order.
464  */
465 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
466 		void *buf, int bufsize)
467 {
468 	struct usb_serial *serial = port->serial;
469 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
470 	void *dmabuf;
471 	int result;
472 
473 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
474 	if (!dmabuf) {
475 		/*
476 		 * FIXME Some callers don't bother to check for error,
477 		 * at least give them consistent junk until they are fixed
478 		 */
479 		memset(buf, 0, bufsize);
480 		return -ENOMEM;
481 	}
482 
483 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
484 			req, REQTYPE_INTERFACE_TO_HOST, 0,
485 			port_priv->bInterfaceNumber, dmabuf, bufsize,
486 			USB_CTRL_SET_TIMEOUT);
487 	if (result == bufsize) {
488 		memcpy(buf, dmabuf, bufsize);
489 		result = 0;
490 	} else {
491 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
492 				req, bufsize, result);
493 		if (result >= 0)
494 			result = -EIO;
495 
496 		/*
497 		 * FIXME Some callers don't bother to check for error,
498 		 * at least give them consistent junk until they are fixed
499 		 */
500 		memset(buf, 0, bufsize);
501 	}
502 
503 	kfree(dmabuf);
504 
505 	return result;
506 }
507 
508 /*
509  * Reads any 32-bit CP210X_ register identified by req.
510  */
511 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
512 {
513 	__le32 le32_val;
514 	int err;
515 
516 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
517 	if (err) {
518 		/*
519 		 * FIXME Some callers don't bother to check for error,
520 		 * at least give them consistent junk until they are fixed
521 		 */
522 		*val = 0;
523 		return err;
524 	}
525 
526 	*val = le32_to_cpu(le32_val);
527 
528 	return 0;
529 }
530 
531 /*
532  * Reads any 16-bit CP210X_ register identified by req.
533  */
534 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
535 {
536 	__le16 le16_val;
537 	int err;
538 
539 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
540 	if (err)
541 		return err;
542 
543 	*val = le16_to_cpu(le16_val);
544 
545 	return 0;
546 }
547 
548 /*
549  * Reads any 8-bit CP210X_ register identified by req.
550  */
551 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
552 {
553 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
554 }
555 
556 /*
557  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
558  * Returns data into buf in native USB byte order.
559  */
560 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
561 				    void *buf, int bufsize)
562 {
563 	void *dmabuf;
564 	int result;
565 
566 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
567 	if (!dmabuf)
568 		return -ENOMEM;
569 
570 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
571 				 CP210X_VENDOR_SPECIFIC, type, val,
572 				 cp210x_interface_num(serial), dmabuf, bufsize,
573 				 USB_CTRL_GET_TIMEOUT);
574 	if (result == bufsize) {
575 		memcpy(buf, dmabuf, bufsize);
576 		result = 0;
577 	} else {
578 		dev_err(&serial->interface->dev,
579 			"failed to get vendor val 0x%04x size %d: %d\n", val,
580 			bufsize, result);
581 		if (result >= 0)
582 			result = -EIO;
583 	}
584 
585 	kfree(dmabuf);
586 
587 	return result;
588 }
589 
590 /*
591  * Writes any 16-bit CP210X_ register (req) whose value is passed
592  * entirely in the wValue field of the USB request.
593  */
594 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
595 {
596 	struct usb_serial *serial = port->serial;
597 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
598 	int result;
599 
600 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
601 			req, REQTYPE_HOST_TO_INTERFACE, val,
602 			port_priv->bInterfaceNumber, NULL, 0,
603 			USB_CTRL_SET_TIMEOUT);
604 	if (result < 0) {
605 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
606 				req, result);
607 	}
608 
609 	return result;
610 }
611 
612 /*
613  * Writes a variable-sized block of CP210X_ registers, identified by req.
614  * Data in buf must be in native USB byte order.
615  */
616 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
617 		void *buf, int bufsize)
618 {
619 	struct usb_serial *serial = port->serial;
620 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
621 	void *dmabuf;
622 	int result;
623 
624 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
625 	if (!dmabuf)
626 		return -ENOMEM;
627 
628 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
629 			req, REQTYPE_HOST_TO_INTERFACE, 0,
630 			port_priv->bInterfaceNumber, dmabuf, bufsize,
631 			USB_CTRL_SET_TIMEOUT);
632 
633 	kfree(dmabuf);
634 
635 	if (result == bufsize) {
636 		result = 0;
637 	} else {
638 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
639 				req, bufsize, result);
640 		if (result >= 0)
641 			result = -EIO;
642 	}
643 
644 	return result;
645 }
646 
647 /*
648  * Writes any 32-bit CP210X_ register identified by req.
649  */
650 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
651 {
652 	__le32 le32_val;
653 
654 	le32_val = cpu_to_le32(val);
655 
656 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
657 }
658 
659 #ifdef CONFIG_GPIOLIB
660 /*
661  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
662  * Data in buf must be in native USB byte order.
663  */
664 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
665 				     u16 val, void *buf, int bufsize)
666 {
667 	void *dmabuf;
668 	int result;
669 
670 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
671 	if (!dmabuf)
672 		return -ENOMEM;
673 
674 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
675 				 CP210X_VENDOR_SPECIFIC, type, val,
676 				 cp210x_interface_num(serial), dmabuf, bufsize,
677 				 USB_CTRL_SET_TIMEOUT);
678 
679 	kfree(dmabuf);
680 
681 	if (result == bufsize) {
682 		result = 0;
683 	} else {
684 		dev_err(&serial->interface->dev,
685 			"failed to set vendor val 0x%04x size %d: %d\n", val,
686 			bufsize, result);
687 		if (result >= 0)
688 			result = -EIO;
689 	}
690 
691 	return result;
692 }
693 #endif
694 
695 /*
696  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
697  * Write a known good value 0x800, read it back.
698  * If it comes back swapped the bug is detected.
699  * Preserve the original register value.
700  */
701 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
702 {
703 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
704 	u16 line_ctl_save;
705 	u16 line_ctl_test;
706 	int err;
707 
708 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
709 	if (err)
710 		return err;
711 
712 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
713 	if (err)
714 		return err;
715 
716 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
717 	if (err)
718 		return err;
719 
720 	if (line_ctl_test == 8) {
721 		port_priv->has_swapped_line_ctl = true;
722 		line_ctl_save = swab16(line_ctl_save);
723 	}
724 
725 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
726 }
727 
728 /*
729  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
730  * to workaround cp2108 bug and get correct value.
731  */
732 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
733 {
734 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
735 	int err;
736 
737 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
738 	if (err)
739 		return err;
740 
741 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
742 	if (port_priv->has_swapped_line_ctl)
743 		*ctl = swab16(*ctl);
744 
745 	return 0;
746 }
747 
748 /*
749  * cp210x_quantise_baudrate
750  * Quantises the baud rate as per AN205 Table 1
751  */
752 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
753 {
754 	if (baud <= 300)
755 		baud = 300;
756 	else if (baud <= 600)      baud = 600;
757 	else if (baud <= 1200)     baud = 1200;
758 	else if (baud <= 1800)     baud = 1800;
759 	else if (baud <= 2400)     baud = 2400;
760 	else if (baud <= 4000)     baud = 4000;
761 	else if (baud <= 4803)     baud = 4800;
762 	else if (baud <= 7207)     baud = 7200;
763 	else if (baud <= 9612)     baud = 9600;
764 	else if (baud <= 14428)    baud = 14400;
765 	else if (baud <= 16062)    baud = 16000;
766 	else if (baud <= 19250)    baud = 19200;
767 	else if (baud <= 28912)    baud = 28800;
768 	else if (baud <= 38601)    baud = 38400;
769 	else if (baud <= 51558)    baud = 51200;
770 	else if (baud <= 56280)    baud = 56000;
771 	else if (baud <= 58053)    baud = 57600;
772 	else if (baud <= 64111)    baud = 64000;
773 	else if (baud <= 77608)    baud = 76800;
774 	else if (baud <= 117028)   baud = 115200;
775 	else if (baud <= 129347)   baud = 128000;
776 	else if (baud <= 156868)   baud = 153600;
777 	else if (baud <= 237832)   baud = 230400;
778 	else if (baud <= 254234)   baud = 250000;
779 	else if (baud <= 273066)   baud = 256000;
780 	else if (baud <= 491520)   baud = 460800;
781 	else if (baud <= 567138)   baud = 500000;
782 	else if (baud <= 670254)   baud = 576000;
783 	else if (baud < 1000000)
784 		baud = 921600;
785 	else if (baud > 2000000)
786 		baud = 2000000;
787 	return baud;
788 }
789 
790 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
791 {
792 	int result;
793 
794 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
795 	if (result) {
796 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
797 		return result;
798 	}
799 
800 	/* Configure the termios structure */
801 	cp210x_get_termios(tty, port);
802 
803 	/* The baud rate must be initialised on cp2104 */
804 	if (tty)
805 		cp210x_change_speed(tty, port, NULL);
806 
807 	return usb_serial_generic_open(tty, port);
808 }
809 
810 static void cp210x_close(struct usb_serial_port *port)
811 {
812 	usb_serial_generic_close(port);
813 
814 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
815 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
816 
817 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
818 }
819 
820 /*
821  * Read how many bytes are waiting in the TX queue.
822  */
823 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
824 		u32 *count)
825 {
826 	struct usb_serial *serial = port->serial;
827 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
828 	struct cp210x_comm_status *sts;
829 	int result;
830 
831 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
832 	if (!sts)
833 		return -ENOMEM;
834 
835 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
836 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
837 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
838 			USB_CTRL_GET_TIMEOUT);
839 	if (result == sizeof(*sts)) {
840 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
841 		result = 0;
842 	} else {
843 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
844 		if (result >= 0)
845 			result = -EIO;
846 	}
847 
848 	kfree(sts);
849 
850 	return result;
851 }
852 
853 static bool cp210x_tx_empty(struct usb_serial_port *port)
854 {
855 	int err;
856 	u32 count;
857 
858 	err = cp210x_get_tx_queue_byte_count(port, &count);
859 	if (err)
860 		return true;
861 
862 	return !count;
863 }
864 
865 /*
866  * cp210x_get_termios
867  * Reads the baud rate, data bits, parity, stop bits and flow control mode
868  * from the device, corrects any unsupported values, and configures the
869  * termios structure to reflect the state of the device
870  */
871 static void cp210x_get_termios(struct tty_struct *tty,
872 	struct usb_serial_port *port)
873 {
874 	unsigned int baud;
875 
876 	if (tty) {
877 		cp210x_get_termios_port(tty->driver_data,
878 			&tty->termios.c_cflag, &baud);
879 		tty_encode_baud_rate(tty, baud, baud);
880 	} else {
881 		tcflag_t cflag;
882 		cflag = 0;
883 		cp210x_get_termios_port(port, &cflag, &baud);
884 	}
885 }
886 
887 /*
888  * cp210x_get_termios_port
889  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
890  */
891 static void cp210x_get_termios_port(struct usb_serial_port *port,
892 	tcflag_t *cflagp, unsigned int *baudp)
893 {
894 	struct device *dev = &port->dev;
895 	tcflag_t cflag;
896 	struct cp210x_flow_ctl flow_ctl;
897 	u32 baud;
898 	u16 bits;
899 	u32 ctl_hs;
900 
901 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
902 
903 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
904 	*baudp = baud;
905 
906 	cflag = *cflagp;
907 
908 	cp210x_get_line_ctl(port, &bits);
909 	cflag &= ~CSIZE;
910 	switch (bits & BITS_DATA_MASK) {
911 	case BITS_DATA_5:
912 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
913 		cflag |= CS5;
914 		break;
915 	case BITS_DATA_6:
916 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
917 		cflag |= CS6;
918 		break;
919 	case BITS_DATA_7:
920 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
921 		cflag |= CS7;
922 		break;
923 	case BITS_DATA_8:
924 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
925 		cflag |= CS8;
926 		break;
927 	case BITS_DATA_9:
928 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
929 		cflag |= CS8;
930 		bits &= ~BITS_DATA_MASK;
931 		bits |= BITS_DATA_8;
932 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
933 		break;
934 	default:
935 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
936 		cflag |= CS8;
937 		bits &= ~BITS_DATA_MASK;
938 		bits |= BITS_DATA_8;
939 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
940 		break;
941 	}
942 
943 	switch (bits & BITS_PARITY_MASK) {
944 	case BITS_PARITY_NONE:
945 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
946 		cflag &= ~PARENB;
947 		break;
948 	case BITS_PARITY_ODD:
949 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
950 		cflag |= (PARENB|PARODD);
951 		break;
952 	case BITS_PARITY_EVEN:
953 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
954 		cflag &= ~PARODD;
955 		cflag |= PARENB;
956 		break;
957 	case BITS_PARITY_MARK:
958 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
959 		cflag |= (PARENB|PARODD|CMSPAR);
960 		break;
961 	case BITS_PARITY_SPACE:
962 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
963 		cflag &= ~PARODD;
964 		cflag |= (PARENB|CMSPAR);
965 		break;
966 	default:
967 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
968 		cflag &= ~PARENB;
969 		bits &= ~BITS_PARITY_MASK;
970 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
971 		break;
972 	}
973 
974 	cflag &= ~CSTOPB;
975 	switch (bits & BITS_STOP_MASK) {
976 	case BITS_STOP_1:
977 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
978 		break;
979 	case BITS_STOP_1_5:
980 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
981 		bits &= ~BITS_STOP_MASK;
982 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
983 		break;
984 	case BITS_STOP_2:
985 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
986 		cflag |= CSTOPB;
987 		break;
988 	default:
989 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
990 		bits &= ~BITS_STOP_MASK;
991 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
992 		break;
993 	}
994 
995 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
996 			sizeof(flow_ctl));
997 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
998 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
999 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1000 		cflag |= CRTSCTS;
1001 	} else {
1002 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1003 		cflag &= ~CRTSCTS;
1004 	}
1005 
1006 	*cflagp = cflag;
1007 }
1008 
1009 /*
1010  * CP2101 supports the following baud rates:
1011  *
1012  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1013  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1014  *
1015  * CP2102 and CP2103 support the following additional rates:
1016  *
1017  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1018  *	576000
1019  *
1020  * The device will map a requested rate to a supported one, but the result
1021  * of requests for rates greater than 1053257 is undefined (see AN205).
1022  *
1023  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1024  * respectively, with an error less than 1%. The actual rates are determined
1025  * by
1026  *
1027  *	div = round(freq / (2 x prescale x request))
1028  *	actual = freq / (2 x prescale x div)
1029  *
1030  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1031  * or 1 otherwise.
1032  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1033  * otherwise.
1034  */
1035 static void cp210x_change_speed(struct tty_struct *tty,
1036 		struct usb_serial_port *port, struct ktermios *old_termios)
1037 {
1038 	u32 baud;
1039 
1040 	baud = tty->termios.c_ospeed;
1041 
1042 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
1043 	 * or to an arbitrary rate in [1M,2M].
1044 	 *
1045 	 * NOTE: B0 is not implemented.
1046 	 */
1047 	baud = cp210x_quantise_baudrate(baud);
1048 
1049 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1050 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1051 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1052 		if (old_termios)
1053 			baud = old_termios->c_ospeed;
1054 		else
1055 			baud = 9600;
1056 	}
1057 
1058 	tty_encode_baud_rate(tty, baud, baud);
1059 }
1060 
1061 static void cp210x_set_termios(struct tty_struct *tty,
1062 		struct usb_serial_port *port, struct ktermios *old_termios)
1063 {
1064 	struct device *dev = &port->dev;
1065 	unsigned int cflag, old_cflag;
1066 	u16 bits;
1067 
1068 	cflag = tty->termios.c_cflag;
1069 	old_cflag = old_termios->c_cflag;
1070 
1071 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1072 		cp210x_change_speed(tty, port, old_termios);
1073 
1074 	/* If the number of data bits is to be updated */
1075 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1076 		cp210x_get_line_ctl(port, &bits);
1077 		bits &= ~BITS_DATA_MASK;
1078 		switch (cflag & CSIZE) {
1079 		case CS5:
1080 			bits |= BITS_DATA_5;
1081 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1082 			break;
1083 		case CS6:
1084 			bits |= BITS_DATA_6;
1085 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1086 			break;
1087 		case CS7:
1088 			bits |= BITS_DATA_7;
1089 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1090 			break;
1091 		case CS8:
1092 		default:
1093 			bits |= BITS_DATA_8;
1094 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1095 			break;
1096 		}
1097 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1098 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1099 	}
1100 
1101 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1102 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1103 		cp210x_get_line_ctl(port, &bits);
1104 		bits &= ~BITS_PARITY_MASK;
1105 		if (cflag & PARENB) {
1106 			if (cflag & CMSPAR) {
1107 				if (cflag & PARODD) {
1108 					bits |= BITS_PARITY_MARK;
1109 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1110 				} else {
1111 					bits |= BITS_PARITY_SPACE;
1112 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1113 				}
1114 			} else {
1115 				if (cflag & PARODD) {
1116 					bits |= BITS_PARITY_ODD;
1117 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1118 				} else {
1119 					bits |= BITS_PARITY_EVEN;
1120 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1121 				}
1122 			}
1123 		}
1124 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1125 			dev_dbg(dev, "Parity mode not supported by device\n");
1126 	}
1127 
1128 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1129 		cp210x_get_line_ctl(port, &bits);
1130 		bits &= ~BITS_STOP_MASK;
1131 		if (cflag & CSTOPB) {
1132 			bits |= BITS_STOP_2;
1133 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1134 		} else {
1135 			bits |= BITS_STOP_1;
1136 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1137 		}
1138 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1139 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1140 	}
1141 
1142 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1143 		struct cp210x_flow_ctl flow_ctl;
1144 		u32 ctl_hs;
1145 		u32 flow_repl;
1146 
1147 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1148 				sizeof(flow_ctl));
1149 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1150 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1151 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1152 				__func__, ctl_hs, flow_repl);
1153 
1154 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1155 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1156 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1157 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1158 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1159 		if (cflag & CRTSCTS) {
1160 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1161 
1162 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1163 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1164 					CP210X_SERIAL_RTS_FLOW_CTL);
1165 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1166 		} else {
1167 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1168 
1169 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1170 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1171 					CP210X_SERIAL_RTS_ACTIVE);
1172 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1173 		}
1174 
1175 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1176 				__func__, ctl_hs, flow_repl);
1177 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1178 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1179 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1180 				sizeof(flow_ctl));
1181 	}
1182 
1183 }
1184 
1185 static int cp210x_tiocmset(struct tty_struct *tty,
1186 		unsigned int set, unsigned int clear)
1187 {
1188 	struct usb_serial_port *port = tty->driver_data;
1189 	return cp210x_tiocmset_port(port, set, clear);
1190 }
1191 
1192 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1193 		unsigned int set, unsigned int clear)
1194 {
1195 	u16 control = 0;
1196 
1197 	if (set & TIOCM_RTS) {
1198 		control |= CONTROL_RTS;
1199 		control |= CONTROL_WRITE_RTS;
1200 	}
1201 	if (set & TIOCM_DTR) {
1202 		control |= CONTROL_DTR;
1203 		control |= CONTROL_WRITE_DTR;
1204 	}
1205 	if (clear & TIOCM_RTS) {
1206 		control &= ~CONTROL_RTS;
1207 		control |= CONTROL_WRITE_RTS;
1208 	}
1209 	if (clear & TIOCM_DTR) {
1210 		control &= ~CONTROL_DTR;
1211 		control |= CONTROL_WRITE_DTR;
1212 	}
1213 
1214 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1215 
1216 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1217 }
1218 
1219 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1220 {
1221 	if (on)
1222 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1223 	else
1224 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1225 }
1226 
1227 static int cp210x_tiocmget(struct tty_struct *tty)
1228 {
1229 	struct usb_serial_port *port = tty->driver_data;
1230 	u8 control;
1231 	int result;
1232 
1233 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1234 	if (result)
1235 		return result;
1236 
1237 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1238 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1239 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1240 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1241 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1242 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1243 
1244 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1245 
1246 	return result;
1247 }
1248 
1249 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1250 {
1251 	struct usb_serial_port *port = tty->driver_data;
1252 	u16 state;
1253 
1254 	if (break_state == 0)
1255 		state = BREAK_OFF;
1256 	else
1257 		state = BREAK_ON;
1258 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1259 		state == BREAK_OFF ? "off" : "on");
1260 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1261 }
1262 
1263 #ifdef CONFIG_GPIOLIB
1264 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1265 {
1266 	struct usb_serial *serial = gpiochip_get_data(gc);
1267 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1268 
1269 	switch (offset) {
1270 	case 0:
1271 		if (priv->config & CP2105_GPIO0_TXLED_MODE)
1272 			return -ENODEV;
1273 		break;
1274 	case 1:
1275 		if (priv->config & (CP2105_GPIO1_RXLED_MODE |
1276 				    CP2105_GPIO1_RS485_MODE))
1277 			return -ENODEV;
1278 		break;
1279 	}
1280 
1281 	return 0;
1282 }
1283 
1284 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1285 {
1286 	struct usb_serial *serial = gpiochip_get_data(gc);
1287 	int result;
1288 	u8 buf;
1289 
1290 	result = cp210x_read_vendor_block(serial, REQTYPE_INTERFACE_TO_HOST,
1291 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1292 	if (result < 0)
1293 		return result;
1294 
1295 	return !!(buf & BIT(gpio));
1296 }
1297 
1298 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1299 {
1300 	struct usb_serial *serial = gpiochip_get_data(gc);
1301 	struct cp210x_gpio_write buf;
1302 
1303 	if (value == 1)
1304 		buf.state = BIT(gpio);
1305 	else
1306 		buf.state = 0;
1307 
1308 	buf.mask = BIT(gpio);
1309 
1310 	cp210x_write_vendor_block(serial, REQTYPE_HOST_TO_INTERFACE,
1311 				  CP210X_WRITE_LATCH, &buf, sizeof(buf));
1312 }
1313 
1314 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1315 {
1316 	/* Hardware does not support an input mode */
1317 	return 0;
1318 }
1319 
1320 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1321 {
1322 	/* Hardware does not support an input mode */
1323 	return -ENOTSUPP;
1324 }
1325 
1326 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1327 					int value)
1328 {
1329 	return 0;
1330 }
1331 
1332 static int cp210x_gpio_set_single_ended(struct gpio_chip *gc, unsigned int gpio,
1333 					enum single_ended_mode mode)
1334 {
1335 	struct usb_serial *serial = gpiochip_get_data(gc);
1336 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1337 
1338 	/* Succeed only if in correct mode (this can't be set at runtime) */
1339 	if ((mode == LINE_MODE_PUSH_PULL) && (priv->gpio_mode & BIT(gpio)))
1340 		return 0;
1341 
1342 	if ((mode == LINE_MODE_OPEN_DRAIN) && !(priv->gpio_mode & BIT(gpio)))
1343 		return 0;
1344 
1345 	return -ENOTSUPP;
1346 }
1347 
1348 /*
1349  * This function is for configuring GPIO using shared pins, where other signals
1350  * are made unavailable by configuring the use of GPIO. This is believed to be
1351  * only applicable to the cp2105 at this point, the other devices supported by
1352  * this driver that provide GPIO do so in a way that does not impact other
1353  * signals and are thus expected to have very different initialisation.
1354  */
1355 static int cp2105_shared_gpio_init(struct usb_serial *serial)
1356 {
1357 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1358 	struct cp210x_pin_mode mode;
1359 	struct cp210x_config config;
1360 	u8 intf_num = cp210x_interface_num(serial);
1361 	int result;
1362 
1363 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1364 					  CP210X_GET_DEVICEMODE, &mode,
1365 					  sizeof(mode));
1366 	if (result < 0)
1367 		return result;
1368 
1369 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1370 					  CP210X_GET_PORTCONFIG, &config,
1371 					  sizeof(config));
1372 	if (result < 0)
1373 		return result;
1374 
1375 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1376 	if (intf_num == 0) {
1377 		if (mode.eci == CP210X_PIN_MODE_MODEM)
1378 			return 0;
1379 
1380 		priv->config = config.eci_cfg;
1381 		priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) &
1382 						CP210X_ECI_GPIO_MODE_MASK) >>
1383 						CP210X_ECI_GPIO_MODE_OFFSET);
1384 		priv->gc.ngpio = 2;
1385 	} else if (intf_num == 1) {
1386 		if (mode.sci == CP210X_PIN_MODE_MODEM)
1387 			return 0;
1388 
1389 		priv->config = config.sci_cfg;
1390 		priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) &
1391 						CP210X_SCI_GPIO_MODE_MASK) >>
1392 						CP210X_SCI_GPIO_MODE_OFFSET);
1393 		priv->gc.ngpio = 3;
1394 	} else {
1395 		return -ENODEV;
1396 	}
1397 
1398 	priv->gc.label = "cp210x";
1399 	priv->gc.request = cp210x_gpio_request;
1400 	priv->gc.get_direction = cp210x_gpio_direction_get;
1401 	priv->gc.direction_input = cp210x_gpio_direction_input;
1402 	priv->gc.direction_output = cp210x_gpio_direction_output;
1403 	priv->gc.get = cp210x_gpio_get;
1404 	priv->gc.set = cp210x_gpio_set;
1405 	priv->gc.set_single_ended = cp210x_gpio_set_single_ended;
1406 	priv->gc.owner = THIS_MODULE;
1407 	priv->gc.parent = &serial->interface->dev;
1408 	priv->gc.base = -1;
1409 	priv->gc.can_sleep = true;
1410 
1411 	result = gpiochip_add_data(&priv->gc, serial);
1412 	if (!result)
1413 		priv->gpio_registered = true;
1414 
1415 	return result;
1416 }
1417 
1418 static void cp210x_gpio_remove(struct usb_serial *serial)
1419 {
1420 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1421 
1422 	if (priv->gpio_registered) {
1423 		gpiochip_remove(&priv->gc);
1424 		priv->gpio_registered = false;
1425 	}
1426 }
1427 
1428 #else
1429 
1430 static int cp2105_shared_gpio_init(struct usb_serial *serial)
1431 {
1432 	return 0;
1433 }
1434 
1435 static void cp210x_gpio_remove(struct usb_serial *serial)
1436 {
1437 	/* Nothing to do */
1438 }
1439 
1440 #endif
1441 
1442 static int cp210x_port_probe(struct usb_serial_port *port)
1443 {
1444 	struct usb_serial *serial = port->serial;
1445 	struct cp210x_port_private *port_priv;
1446 	int ret;
1447 
1448 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1449 	if (!port_priv)
1450 		return -ENOMEM;
1451 
1452 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1453 
1454 	usb_set_serial_port_data(port, port_priv);
1455 
1456 	ret = cp210x_detect_swapped_line_ctl(port);
1457 	if (ret) {
1458 		kfree(port_priv);
1459 		return ret;
1460 	}
1461 
1462 	return 0;
1463 }
1464 
1465 static int cp210x_port_remove(struct usb_serial_port *port)
1466 {
1467 	struct cp210x_port_private *port_priv;
1468 
1469 	port_priv = usb_get_serial_port_data(port);
1470 	kfree(port_priv);
1471 
1472 	return 0;
1473 }
1474 
1475 static int cp210x_attach(struct usb_serial *serial)
1476 {
1477 	int result;
1478 	struct cp210x_serial_private *priv;
1479 
1480 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1481 	if (!priv)
1482 		return -ENOMEM;
1483 
1484 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1485 					  CP210X_GET_PARTNUM, &priv->partnum,
1486 					  sizeof(priv->partnum));
1487 	if (result < 0)
1488 		goto err_free_priv;
1489 
1490 	usb_set_serial_data(serial, priv);
1491 
1492 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1493 		result = cp2105_shared_gpio_init(serial);
1494 		if (result < 0) {
1495 			dev_err(&serial->interface->dev,
1496 				"GPIO initialisation failed, continuing without GPIO support\n");
1497 		}
1498 	}
1499 
1500 	return 0;
1501 err_free_priv:
1502 	kfree(priv);
1503 
1504 	return result;
1505 }
1506 
1507 static void cp210x_disconnect(struct usb_serial *serial)
1508 {
1509 	cp210x_gpio_remove(serial);
1510 }
1511 
1512 static void cp210x_release(struct usb_serial *serial)
1513 {
1514 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1515 
1516 	cp210x_gpio_remove(serial);
1517 
1518 	kfree(priv);
1519 }
1520 
1521 module_usb_serial_driver(serial_drivers, id_table);
1522 
1523 MODULE_DESCRIPTION(DRIVER_DESC);
1524 MODULE_LICENSE("GPL");
1525