xref: /linux/drivers/usb/serial/cp210x.c (revision d14ac576d10f865970bb1324d337e5e24d79aaf4)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Silicon Laboratories CP210x USB to RS232 serial adaptor driver
4  *
5  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
6  *
7  * Support to set flow control line levels using TIOCMGET and TIOCMSET
8  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
9  * control thanks to Munir Nassar nassarmu@real-time.com
10  *
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/tty.h>
17 #include <linux/tty_flip.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/usb.h>
21 #include <linux/uaccess.h>
22 #include <linux/usb/serial.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/bitops.h>
25 #include <linux/mutex.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 	tcflag_t *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_attach(struct usb_serial *);
48 static void cp210x_disconnect(struct usb_serial *);
49 static void cp210x_release(struct usb_serial *);
50 static int cp210x_port_probe(struct usb_serial_port *);
51 static int cp210x_port_remove(struct usb_serial_port *);
52 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
53 
54 static const struct usb_device_id id_table[] = {
55 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
56 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
57 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
58 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
59 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
60 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
61 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
62 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
63 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
64 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
65 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
66 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
67 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
68 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
69 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
70 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
71 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
72 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
73 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
74 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
75 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
76 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
77 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
78 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
79 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
80 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
81 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
82 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
83 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
84 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
85 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
86 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
87 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
88 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
89 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
90 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
91 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
92 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
93 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
94 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
95 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
96 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
97 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
98 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
99 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
100 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
101 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
102 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
103 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
104 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
105 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
106 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
107 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
108 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
109 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
110 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
111 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
112 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
113 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
114 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
115 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
116 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
117 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
118 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
119 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
120 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
121 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
122 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
123 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
124 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
125 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
126 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
127 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
128 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
129 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
130 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
131 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
132 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
133 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
134 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
135 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
136 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
137 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
138 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
139 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
140 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
141 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
142 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
143 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
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(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
179 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
180 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
181 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
182 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
183 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
184 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
185 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
186 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
187 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
188 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
189 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
190 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
191 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
192 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
193 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
194 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
195 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
196 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
197 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
198 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
199 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
200 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
201 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
202 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
203 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
204 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
205 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
206 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
207 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
208 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
209 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
210 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
211 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
212 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
213 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
214 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
215 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
216 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
217 	{ } /* Terminating Entry */
218 };
219 
220 MODULE_DEVICE_TABLE(usb, id_table);
221 
222 struct cp210x_serial_private {
223 #ifdef CONFIG_GPIOLIB
224 	struct gpio_chip	gc;
225 	u8			config;
226 	u8			gpio_mode;
227 	bool			gpio_registered;
228 #endif
229 	u8			partnum;
230 };
231 
232 struct cp210x_port_private {
233 	__u8			bInterfaceNumber;
234 	bool			has_swapped_line_ctl;
235 };
236 
237 static struct usb_serial_driver cp210x_device = {
238 	.driver = {
239 		.owner =	THIS_MODULE,
240 		.name =		"cp210x",
241 	},
242 	.id_table		= id_table,
243 	.num_ports		= 1,
244 	.bulk_in_size		= 256,
245 	.bulk_out_size		= 256,
246 	.open			= cp210x_open,
247 	.close			= cp210x_close,
248 	.break_ctl		= cp210x_break_ctl,
249 	.set_termios		= cp210x_set_termios,
250 	.tx_empty		= cp210x_tx_empty,
251 	.tiocmget		= cp210x_tiocmget,
252 	.tiocmset		= cp210x_tiocmset,
253 	.attach			= cp210x_attach,
254 	.disconnect		= cp210x_disconnect,
255 	.release		= cp210x_release,
256 	.port_probe		= cp210x_port_probe,
257 	.port_remove		= cp210x_port_remove,
258 	.dtr_rts		= cp210x_dtr_rts
259 };
260 
261 static struct usb_serial_driver * const serial_drivers[] = {
262 	&cp210x_device, NULL
263 };
264 
265 /* Config request types */
266 #define REQTYPE_HOST_TO_INTERFACE	0x41
267 #define REQTYPE_INTERFACE_TO_HOST	0xc1
268 #define REQTYPE_HOST_TO_DEVICE	0x40
269 #define REQTYPE_DEVICE_TO_HOST	0xc0
270 
271 /* Config request codes */
272 #define CP210X_IFC_ENABLE	0x00
273 #define CP210X_SET_BAUDDIV	0x01
274 #define CP210X_GET_BAUDDIV	0x02
275 #define CP210X_SET_LINE_CTL	0x03
276 #define CP210X_GET_LINE_CTL	0x04
277 #define CP210X_SET_BREAK	0x05
278 #define CP210X_IMM_CHAR		0x06
279 #define CP210X_SET_MHS		0x07
280 #define CP210X_GET_MDMSTS	0x08
281 #define CP210X_SET_XON		0x09
282 #define CP210X_SET_XOFF		0x0A
283 #define CP210X_SET_EVENTMASK	0x0B
284 #define CP210X_GET_EVENTMASK	0x0C
285 #define CP210X_SET_CHAR		0x0D
286 #define CP210X_GET_CHARS	0x0E
287 #define CP210X_GET_PROPS	0x0F
288 #define CP210X_GET_COMM_STATUS	0x10
289 #define CP210X_RESET		0x11
290 #define CP210X_PURGE		0x12
291 #define CP210X_SET_FLOW		0x13
292 #define CP210X_GET_FLOW		0x14
293 #define CP210X_EMBED_EVENTS	0x15
294 #define CP210X_GET_EVENTSTATE	0x16
295 #define CP210X_SET_CHARS	0x19
296 #define CP210X_GET_BAUDRATE	0x1D
297 #define CP210X_SET_BAUDRATE	0x1E
298 #define CP210X_VENDOR_SPECIFIC	0xFF
299 
300 /* CP210X_IFC_ENABLE */
301 #define UART_ENABLE		0x0001
302 #define UART_DISABLE		0x0000
303 
304 /* CP210X_(SET|GET)_BAUDDIV */
305 #define BAUD_RATE_GEN_FREQ	0x384000
306 
307 /* CP210X_(SET|GET)_LINE_CTL */
308 #define BITS_DATA_MASK		0X0f00
309 #define BITS_DATA_5		0X0500
310 #define BITS_DATA_6		0X0600
311 #define BITS_DATA_7		0X0700
312 #define BITS_DATA_8		0X0800
313 #define BITS_DATA_9		0X0900
314 
315 #define BITS_PARITY_MASK	0x00f0
316 #define BITS_PARITY_NONE	0x0000
317 #define BITS_PARITY_ODD		0x0010
318 #define BITS_PARITY_EVEN	0x0020
319 #define BITS_PARITY_MARK	0x0030
320 #define BITS_PARITY_SPACE	0x0040
321 
322 #define BITS_STOP_MASK		0x000f
323 #define BITS_STOP_1		0x0000
324 #define BITS_STOP_1_5		0x0001
325 #define BITS_STOP_2		0x0002
326 
327 /* CP210X_SET_BREAK */
328 #define BREAK_ON		0x0001
329 #define BREAK_OFF		0x0000
330 
331 /* CP210X_(SET_MHS|GET_MDMSTS) */
332 #define CONTROL_DTR		0x0001
333 #define CONTROL_RTS		0x0002
334 #define CONTROL_CTS		0x0010
335 #define CONTROL_DSR		0x0020
336 #define CONTROL_RING		0x0040
337 #define CONTROL_DCD		0x0080
338 #define CONTROL_WRITE_DTR	0x0100
339 #define CONTROL_WRITE_RTS	0x0200
340 
341 /* CP210X_VENDOR_SPECIFIC values */
342 #define CP210X_READ_LATCH	0x00C2
343 #define CP210X_GET_PARTNUM	0x370B
344 #define CP210X_GET_PORTCONFIG	0x370C
345 #define CP210X_GET_DEVICEMODE	0x3711
346 #define CP210X_WRITE_LATCH	0x37E1
347 
348 /* Part number definitions */
349 #define CP210X_PARTNUM_CP2101	0x01
350 #define CP210X_PARTNUM_CP2102	0x02
351 #define CP210X_PARTNUM_CP2103	0x03
352 #define CP210X_PARTNUM_CP2104	0x04
353 #define CP210X_PARTNUM_CP2105	0x05
354 #define CP210X_PARTNUM_CP2108	0x08
355 #define CP210X_PARTNUM_UNKNOWN	0xFF
356 
357 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
358 struct cp210x_comm_status {
359 	__le32   ulErrors;
360 	__le32   ulHoldReasons;
361 	__le32   ulAmountInInQueue;
362 	__le32   ulAmountInOutQueue;
363 	u8       bEofReceived;
364 	u8       bWaitForImmediate;
365 	u8       bReserved;
366 } __packed;
367 
368 /*
369  * CP210X_PURGE - 16 bits passed in wValue of USB request.
370  * SiLabs app note AN571 gives a strange description of the 4 bits:
371  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
372  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
373  */
374 #define PURGE_ALL		0x000f
375 
376 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
377 struct cp210x_flow_ctl {
378 	__le32	ulControlHandshake;
379 	__le32	ulFlowReplace;
380 	__le32	ulXonLimit;
381 	__le32	ulXoffLimit;
382 } __packed;
383 
384 /* cp210x_flow_ctl::ulControlHandshake */
385 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
386 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
387 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
388 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
389 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
390 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
391 
392 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
393 #define CP210X_SERIAL_DTR_INACTIVE	0
394 #define CP210X_SERIAL_DTR_ACTIVE	1
395 #define CP210X_SERIAL_DTR_FLOW_CTL	2
396 
397 /* cp210x_flow_ctl::ulFlowReplace */
398 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
399 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
400 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
401 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
402 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
403 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
404 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
405 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
406 
407 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
408 #define CP210X_SERIAL_RTS_INACTIVE	0
409 #define CP210X_SERIAL_RTS_ACTIVE	1
410 #define CP210X_SERIAL_RTS_FLOW_CTL	2
411 
412 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
413 struct cp210x_pin_mode {
414 	u8	eci;
415 	u8	sci;
416 } __packed;
417 
418 #define CP210X_PIN_MODE_MODEM		0
419 #define CP210X_PIN_MODE_GPIO		BIT(0)
420 
421 /*
422  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes.
423  * Structure needs padding due to unused/unspecified bytes.
424  */
425 struct cp210x_config {
426 	__le16	gpio_mode;
427 	u8	__pad0[2];
428 	__le16	reset_state;
429 	u8	__pad1[4];
430 	__le16	suspend_state;
431 	u8	sci_cfg;
432 	u8	eci_cfg;
433 	u8	device_cfg;
434 } __packed;
435 
436 /* GPIO modes */
437 #define CP210X_SCI_GPIO_MODE_OFFSET	9
438 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
439 
440 #define CP210X_ECI_GPIO_MODE_OFFSET	2
441 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
442 
443 /* CP2105 port configuration values */
444 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
445 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
446 #define CP2105_GPIO1_RS485_MODE		BIT(2)
447 
448 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
449 struct cp210x_gpio_write {
450 	u8	mask;
451 	u8	state;
452 } __packed;
453 
454 /*
455  * Helper to get interface number when we only have struct usb_serial.
456  */
457 static u8 cp210x_interface_num(struct usb_serial *serial)
458 {
459 	struct usb_host_interface *cur_altsetting;
460 
461 	cur_altsetting = serial->interface->cur_altsetting;
462 
463 	return cur_altsetting->desc.bInterfaceNumber;
464 }
465 
466 /*
467  * Reads a variable-sized block of CP210X_ registers, identified by req.
468  * Returns data into buf in native USB byte order.
469  */
470 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
471 		void *buf, int bufsize)
472 {
473 	struct usb_serial *serial = port->serial;
474 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
475 	void *dmabuf;
476 	int result;
477 
478 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
479 	if (!dmabuf) {
480 		/*
481 		 * FIXME Some callers don't bother to check for error,
482 		 * at least give them consistent junk until they are fixed
483 		 */
484 		memset(buf, 0, bufsize);
485 		return -ENOMEM;
486 	}
487 
488 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
489 			req, REQTYPE_INTERFACE_TO_HOST, 0,
490 			port_priv->bInterfaceNumber, dmabuf, bufsize,
491 			USB_CTRL_SET_TIMEOUT);
492 	if (result == bufsize) {
493 		memcpy(buf, dmabuf, bufsize);
494 		result = 0;
495 	} else {
496 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
497 				req, bufsize, result);
498 		if (result >= 0)
499 			result = -EIO;
500 
501 		/*
502 		 * FIXME Some callers don't bother to check for error,
503 		 * at least give them consistent junk until they are fixed
504 		 */
505 		memset(buf, 0, bufsize);
506 	}
507 
508 	kfree(dmabuf);
509 
510 	return result;
511 }
512 
513 /*
514  * Reads any 32-bit CP210X_ register identified by req.
515  */
516 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
517 {
518 	__le32 le32_val;
519 	int err;
520 
521 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
522 	if (err) {
523 		/*
524 		 * FIXME Some callers don't bother to check for error,
525 		 * at least give them consistent junk until they are fixed
526 		 */
527 		*val = 0;
528 		return err;
529 	}
530 
531 	*val = le32_to_cpu(le32_val);
532 
533 	return 0;
534 }
535 
536 /*
537  * Reads any 16-bit CP210X_ register identified by req.
538  */
539 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
540 {
541 	__le16 le16_val;
542 	int err;
543 
544 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
545 	if (err)
546 		return err;
547 
548 	*val = le16_to_cpu(le16_val);
549 
550 	return 0;
551 }
552 
553 /*
554  * Reads any 8-bit CP210X_ register identified by req.
555  */
556 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
557 {
558 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
559 }
560 
561 /*
562  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
563  * Returns data into buf in native USB byte order.
564  */
565 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
566 				    void *buf, int bufsize)
567 {
568 	void *dmabuf;
569 	int result;
570 
571 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
572 	if (!dmabuf)
573 		return -ENOMEM;
574 
575 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
576 				 CP210X_VENDOR_SPECIFIC, type, val,
577 				 cp210x_interface_num(serial), dmabuf, bufsize,
578 				 USB_CTRL_GET_TIMEOUT);
579 	if (result == bufsize) {
580 		memcpy(buf, dmabuf, bufsize);
581 		result = 0;
582 	} else {
583 		dev_err(&serial->interface->dev,
584 			"failed to get vendor val 0x%04x size %d: %d\n", val,
585 			bufsize, result);
586 		if (result >= 0)
587 			result = -EIO;
588 	}
589 
590 	kfree(dmabuf);
591 
592 	return result;
593 }
594 
595 /*
596  * Writes any 16-bit CP210X_ register (req) whose value is passed
597  * entirely in the wValue field of the USB request.
598  */
599 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
600 {
601 	struct usb_serial *serial = port->serial;
602 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
603 	int result;
604 
605 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
606 			req, REQTYPE_HOST_TO_INTERFACE, val,
607 			port_priv->bInterfaceNumber, NULL, 0,
608 			USB_CTRL_SET_TIMEOUT);
609 	if (result < 0) {
610 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
611 				req, result);
612 	}
613 
614 	return result;
615 }
616 
617 /*
618  * Writes a variable-sized block of CP210X_ registers, identified by req.
619  * Data in buf must be in native USB byte order.
620  */
621 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
622 		void *buf, int bufsize)
623 {
624 	struct usb_serial *serial = port->serial;
625 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
626 	void *dmabuf;
627 	int result;
628 
629 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
630 	if (!dmabuf)
631 		return -ENOMEM;
632 
633 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
634 			req, REQTYPE_HOST_TO_INTERFACE, 0,
635 			port_priv->bInterfaceNumber, dmabuf, bufsize,
636 			USB_CTRL_SET_TIMEOUT);
637 
638 	kfree(dmabuf);
639 
640 	if (result == bufsize) {
641 		result = 0;
642 	} else {
643 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
644 				req, bufsize, result);
645 		if (result >= 0)
646 			result = -EIO;
647 	}
648 
649 	return result;
650 }
651 
652 /*
653  * Writes any 32-bit CP210X_ register identified by req.
654  */
655 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
656 {
657 	__le32 le32_val;
658 
659 	le32_val = cpu_to_le32(val);
660 
661 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
662 }
663 
664 #ifdef CONFIG_GPIOLIB
665 /*
666  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
667  * Data in buf must be in native USB byte order.
668  */
669 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
670 				     u16 val, void *buf, int bufsize)
671 {
672 	void *dmabuf;
673 	int result;
674 
675 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
676 	if (!dmabuf)
677 		return -ENOMEM;
678 
679 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
680 				 CP210X_VENDOR_SPECIFIC, type, val,
681 				 cp210x_interface_num(serial), dmabuf, bufsize,
682 				 USB_CTRL_SET_TIMEOUT);
683 
684 	kfree(dmabuf);
685 
686 	if (result == bufsize) {
687 		result = 0;
688 	} else {
689 		dev_err(&serial->interface->dev,
690 			"failed to set vendor val 0x%04x size %d: %d\n", val,
691 			bufsize, result);
692 		if (result >= 0)
693 			result = -EIO;
694 	}
695 
696 	return result;
697 }
698 #endif
699 
700 /*
701  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
702  * Write a known good value 0x800, read it back.
703  * If it comes back swapped the bug is detected.
704  * Preserve the original register value.
705  */
706 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
707 {
708 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
709 	u16 line_ctl_save;
710 	u16 line_ctl_test;
711 	int err;
712 
713 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
714 	if (err)
715 		return err;
716 
717 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
718 	if (err)
719 		return err;
720 
721 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
722 	if (err)
723 		return err;
724 
725 	if (line_ctl_test == 8) {
726 		port_priv->has_swapped_line_ctl = true;
727 		line_ctl_save = swab16(line_ctl_save);
728 	}
729 
730 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
731 }
732 
733 /*
734  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
735  * to workaround cp2108 bug and get correct value.
736  */
737 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
738 {
739 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
740 	int err;
741 
742 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
743 	if (err)
744 		return err;
745 
746 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
747 	if (port_priv->has_swapped_line_ctl)
748 		*ctl = swab16(*ctl);
749 
750 	return 0;
751 }
752 
753 /*
754  * cp210x_quantise_baudrate
755  * Quantises the baud rate as per AN205 Table 1
756  */
757 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
758 {
759 	if (baud <= 300)
760 		baud = 300;
761 	else if (baud <= 600)      baud = 600;
762 	else if (baud <= 1200)     baud = 1200;
763 	else if (baud <= 1800)     baud = 1800;
764 	else if (baud <= 2400)     baud = 2400;
765 	else if (baud <= 4000)     baud = 4000;
766 	else if (baud <= 4803)     baud = 4800;
767 	else if (baud <= 7207)     baud = 7200;
768 	else if (baud <= 9612)     baud = 9600;
769 	else if (baud <= 14428)    baud = 14400;
770 	else if (baud <= 16062)    baud = 16000;
771 	else if (baud <= 19250)    baud = 19200;
772 	else if (baud <= 28912)    baud = 28800;
773 	else if (baud <= 38601)    baud = 38400;
774 	else if (baud <= 51558)    baud = 51200;
775 	else if (baud <= 56280)    baud = 56000;
776 	else if (baud <= 58053)    baud = 57600;
777 	else if (baud <= 64111)    baud = 64000;
778 	else if (baud <= 77608)    baud = 76800;
779 	else if (baud <= 117028)   baud = 115200;
780 	else if (baud <= 129347)   baud = 128000;
781 	else if (baud <= 156868)   baud = 153600;
782 	else if (baud <= 237832)   baud = 230400;
783 	else if (baud <= 254234)   baud = 250000;
784 	else if (baud <= 273066)   baud = 256000;
785 	else if (baud <= 491520)   baud = 460800;
786 	else if (baud <= 567138)   baud = 500000;
787 	else if (baud <= 670254)   baud = 576000;
788 	else if (baud < 1000000)
789 		baud = 921600;
790 	else if (baud > 2000000)
791 		baud = 2000000;
792 	return baud;
793 }
794 
795 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
796 {
797 	int result;
798 
799 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
800 	if (result) {
801 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
802 		return result;
803 	}
804 
805 	/* Configure the termios structure */
806 	cp210x_get_termios(tty, port);
807 
808 	/* The baud rate must be initialised on cp2104 */
809 	if (tty)
810 		cp210x_change_speed(tty, port, NULL);
811 
812 	return usb_serial_generic_open(tty, port);
813 }
814 
815 static void cp210x_close(struct usb_serial_port *port)
816 {
817 	usb_serial_generic_close(port);
818 
819 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
820 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
821 
822 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
823 }
824 
825 /*
826  * Read how many bytes are waiting in the TX queue.
827  */
828 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
829 		u32 *count)
830 {
831 	struct usb_serial *serial = port->serial;
832 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
833 	struct cp210x_comm_status *sts;
834 	int result;
835 
836 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
837 	if (!sts)
838 		return -ENOMEM;
839 
840 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
841 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
842 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
843 			USB_CTRL_GET_TIMEOUT);
844 	if (result == sizeof(*sts)) {
845 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
846 		result = 0;
847 	} else {
848 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
849 		if (result >= 0)
850 			result = -EIO;
851 	}
852 
853 	kfree(sts);
854 
855 	return result;
856 }
857 
858 static bool cp210x_tx_empty(struct usb_serial_port *port)
859 {
860 	int err;
861 	u32 count;
862 
863 	err = cp210x_get_tx_queue_byte_count(port, &count);
864 	if (err)
865 		return true;
866 
867 	return !count;
868 }
869 
870 /*
871  * cp210x_get_termios
872  * Reads the baud rate, data bits, parity, stop bits and flow control mode
873  * from the device, corrects any unsupported values, and configures the
874  * termios structure to reflect the state of the device
875  */
876 static void cp210x_get_termios(struct tty_struct *tty,
877 	struct usb_serial_port *port)
878 {
879 	unsigned int baud;
880 
881 	if (tty) {
882 		cp210x_get_termios_port(tty->driver_data,
883 			&tty->termios.c_cflag, &baud);
884 		tty_encode_baud_rate(tty, baud, baud);
885 	} else {
886 		tcflag_t cflag;
887 		cflag = 0;
888 		cp210x_get_termios_port(port, &cflag, &baud);
889 	}
890 }
891 
892 /*
893  * cp210x_get_termios_port
894  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
895  */
896 static void cp210x_get_termios_port(struct usb_serial_port *port,
897 	tcflag_t *cflagp, unsigned int *baudp)
898 {
899 	struct device *dev = &port->dev;
900 	tcflag_t cflag;
901 	struct cp210x_flow_ctl flow_ctl;
902 	u32 baud;
903 	u16 bits;
904 	u32 ctl_hs;
905 
906 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
907 
908 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
909 	*baudp = baud;
910 
911 	cflag = *cflagp;
912 
913 	cp210x_get_line_ctl(port, &bits);
914 	cflag &= ~CSIZE;
915 	switch (bits & BITS_DATA_MASK) {
916 	case BITS_DATA_5:
917 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
918 		cflag |= CS5;
919 		break;
920 	case BITS_DATA_6:
921 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
922 		cflag |= CS6;
923 		break;
924 	case BITS_DATA_7:
925 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
926 		cflag |= CS7;
927 		break;
928 	case BITS_DATA_8:
929 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
930 		cflag |= CS8;
931 		break;
932 	case BITS_DATA_9:
933 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
934 		cflag |= CS8;
935 		bits &= ~BITS_DATA_MASK;
936 		bits |= BITS_DATA_8;
937 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
938 		break;
939 	default:
940 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
941 		cflag |= CS8;
942 		bits &= ~BITS_DATA_MASK;
943 		bits |= BITS_DATA_8;
944 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
945 		break;
946 	}
947 
948 	switch (bits & BITS_PARITY_MASK) {
949 	case BITS_PARITY_NONE:
950 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
951 		cflag &= ~PARENB;
952 		break;
953 	case BITS_PARITY_ODD:
954 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
955 		cflag |= (PARENB|PARODD);
956 		break;
957 	case BITS_PARITY_EVEN:
958 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
959 		cflag &= ~PARODD;
960 		cflag |= PARENB;
961 		break;
962 	case BITS_PARITY_MARK:
963 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
964 		cflag |= (PARENB|PARODD|CMSPAR);
965 		break;
966 	case BITS_PARITY_SPACE:
967 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
968 		cflag &= ~PARODD;
969 		cflag |= (PARENB|CMSPAR);
970 		break;
971 	default:
972 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
973 		cflag &= ~PARENB;
974 		bits &= ~BITS_PARITY_MASK;
975 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
976 		break;
977 	}
978 
979 	cflag &= ~CSTOPB;
980 	switch (bits & BITS_STOP_MASK) {
981 	case BITS_STOP_1:
982 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
983 		break;
984 	case BITS_STOP_1_5:
985 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
986 		bits &= ~BITS_STOP_MASK;
987 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
988 		break;
989 	case BITS_STOP_2:
990 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
991 		cflag |= CSTOPB;
992 		break;
993 	default:
994 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
995 		bits &= ~BITS_STOP_MASK;
996 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
997 		break;
998 	}
999 
1000 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1001 			sizeof(flow_ctl));
1002 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1003 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1004 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1005 		cflag |= CRTSCTS;
1006 	} else {
1007 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1008 		cflag &= ~CRTSCTS;
1009 	}
1010 
1011 	*cflagp = cflag;
1012 }
1013 
1014 /*
1015  * CP2101 supports the following baud rates:
1016  *
1017  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1018  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1019  *
1020  * CP2102 and CP2103 support the following additional rates:
1021  *
1022  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1023  *	576000
1024  *
1025  * The device will map a requested rate to a supported one, but the result
1026  * of requests for rates greater than 1053257 is undefined (see AN205).
1027  *
1028  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1029  * respectively, with an error less than 1%. The actual rates are determined
1030  * by
1031  *
1032  *	div = round(freq / (2 x prescale x request))
1033  *	actual = freq / (2 x prescale x div)
1034  *
1035  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1036  * or 1 otherwise.
1037  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1038  * otherwise.
1039  */
1040 static void cp210x_change_speed(struct tty_struct *tty,
1041 		struct usb_serial_port *port, struct ktermios *old_termios)
1042 {
1043 	u32 baud;
1044 
1045 	baud = tty->termios.c_ospeed;
1046 
1047 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
1048 	 * or to an arbitrary rate in [1M,2M].
1049 	 *
1050 	 * NOTE: B0 is not implemented.
1051 	 */
1052 	baud = cp210x_quantise_baudrate(baud);
1053 
1054 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1055 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1056 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1057 		if (old_termios)
1058 			baud = old_termios->c_ospeed;
1059 		else
1060 			baud = 9600;
1061 	}
1062 
1063 	tty_encode_baud_rate(tty, baud, baud);
1064 }
1065 
1066 static void cp210x_set_termios(struct tty_struct *tty,
1067 		struct usb_serial_port *port, struct ktermios *old_termios)
1068 {
1069 	struct device *dev = &port->dev;
1070 	unsigned int cflag, old_cflag;
1071 	u16 bits;
1072 
1073 	cflag = tty->termios.c_cflag;
1074 	old_cflag = old_termios->c_cflag;
1075 
1076 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1077 		cp210x_change_speed(tty, port, old_termios);
1078 
1079 	/* If the number of data bits is to be updated */
1080 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1081 		cp210x_get_line_ctl(port, &bits);
1082 		bits &= ~BITS_DATA_MASK;
1083 		switch (cflag & CSIZE) {
1084 		case CS5:
1085 			bits |= BITS_DATA_5;
1086 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1087 			break;
1088 		case CS6:
1089 			bits |= BITS_DATA_6;
1090 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1091 			break;
1092 		case CS7:
1093 			bits |= BITS_DATA_7;
1094 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1095 			break;
1096 		case CS8:
1097 		default:
1098 			bits |= BITS_DATA_8;
1099 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1100 			break;
1101 		}
1102 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1103 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1104 	}
1105 
1106 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1107 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1108 		cp210x_get_line_ctl(port, &bits);
1109 		bits &= ~BITS_PARITY_MASK;
1110 		if (cflag & PARENB) {
1111 			if (cflag & CMSPAR) {
1112 				if (cflag & PARODD) {
1113 					bits |= BITS_PARITY_MARK;
1114 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1115 				} else {
1116 					bits |= BITS_PARITY_SPACE;
1117 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1118 				}
1119 			} else {
1120 				if (cflag & PARODD) {
1121 					bits |= BITS_PARITY_ODD;
1122 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1123 				} else {
1124 					bits |= BITS_PARITY_EVEN;
1125 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1126 				}
1127 			}
1128 		}
1129 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1130 			dev_dbg(dev, "Parity mode not supported by device\n");
1131 	}
1132 
1133 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1134 		cp210x_get_line_ctl(port, &bits);
1135 		bits &= ~BITS_STOP_MASK;
1136 		if (cflag & CSTOPB) {
1137 			bits |= BITS_STOP_2;
1138 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1139 		} else {
1140 			bits |= BITS_STOP_1;
1141 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1142 		}
1143 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1144 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1145 	}
1146 
1147 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1148 		struct cp210x_flow_ctl flow_ctl;
1149 		u32 ctl_hs;
1150 		u32 flow_repl;
1151 
1152 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1153 				sizeof(flow_ctl));
1154 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1155 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1156 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1157 				__func__, ctl_hs, flow_repl);
1158 
1159 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1160 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1161 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1162 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1163 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1164 		if (cflag & CRTSCTS) {
1165 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1166 
1167 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1168 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1169 					CP210X_SERIAL_RTS_FLOW_CTL);
1170 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1171 		} else {
1172 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1173 
1174 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1175 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1176 					CP210X_SERIAL_RTS_ACTIVE);
1177 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1178 		}
1179 
1180 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1181 				__func__, ctl_hs, flow_repl);
1182 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1183 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1184 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1185 				sizeof(flow_ctl));
1186 	}
1187 
1188 }
1189 
1190 static int cp210x_tiocmset(struct tty_struct *tty,
1191 		unsigned int set, unsigned int clear)
1192 {
1193 	struct usb_serial_port *port = tty->driver_data;
1194 	return cp210x_tiocmset_port(port, set, clear);
1195 }
1196 
1197 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1198 		unsigned int set, unsigned int clear)
1199 {
1200 	u16 control = 0;
1201 
1202 	if (set & TIOCM_RTS) {
1203 		control |= CONTROL_RTS;
1204 		control |= CONTROL_WRITE_RTS;
1205 	}
1206 	if (set & TIOCM_DTR) {
1207 		control |= CONTROL_DTR;
1208 		control |= CONTROL_WRITE_DTR;
1209 	}
1210 	if (clear & TIOCM_RTS) {
1211 		control &= ~CONTROL_RTS;
1212 		control |= CONTROL_WRITE_RTS;
1213 	}
1214 	if (clear & TIOCM_DTR) {
1215 		control &= ~CONTROL_DTR;
1216 		control |= CONTROL_WRITE_DTR;
1217 	}
1218 
1219 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1220 
1221 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1222 }
1223 
1224 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1225 {
1226 	if (on)
1227 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1228 	else
1229 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1230 }
1231 
1232 static int cp210x_tiocmget(struct tty_struct *tty)
1233 {
1234 	struct usb_serial_port *port = tty->driver_data;
1235 	u8 control;
1236 	int result;
1237 
1238 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1239 	if (result)
1240 		return result;
1241 
1242 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1243 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1244 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1245 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1246 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1247 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1248 
1249 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1250 
1251 	return result;
1252 }
1253 
1254 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1255 {
1256 	struct usb_serial_port *port = tty->driver_data;
1257 	u16 state;
1258 
1259 	if (break_state == 0)
1260 		state = BREAK_OFF;
1261 	else
1262 		state = BREAK_ON;
1263 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1264 		state == BREAK_OFF ? "off" : "on");
1265 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1266 }
1267 
1268 #ifdef CONFIG_GPIOLIB
1269 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1270 {
1271 	struct usb_serial *serial = gpiochip_get_data(gc);
1272 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1273 
1274 	switch (offset) {
1275 	case 0:
1276 		if (priv->config & CP2105_GPIO0_TXLED_MODE)
1277 			return -ENODEV;
1278 		break;
1279 	case 1:
1280 		if (priv->config & (CP2105_GPIO1_RXLED_MODE |
1281 				    CP2105_GPIO1_RS485_MODE))
1282 			return -ENODEV;
1283 		break;
1284 	}
1285 
1286 	return 0;
1287 }
1288 
1289 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1290 {
1291 	struct usb_serial *serial = gpiochip_get_data(gc);
1292 	int result;
1293 	u8 buf;
1294 
1295 	result = cp210x_read_vendor_block(serial, REQTYPE_INTERFACE_TO_HOST,
1296 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1297 	if (result < 0)
1298 		return result;
1299 
1300 	return !!(buf & BIT(gpio));
1301 }
1302 
1303 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1304 {
1305 	struct usb_serial *serial = gpiochip_get_data(gc);
1306 	struct cp210x_gpio_write buf;
1307 
1308 	if (value == 1)
1309 		buf.state = BIT(gpio);
1310 	else
1311 		buf.state = 0;
1312 
1313 	buf.mask = BIT(gpio);
1314 
1315 	cp210x_write_vendor_block(serial, REQTYPE_HOST_TO_INTERFACE,
1316 				  CP210X_WRITE_LATCH, &buf, sizeof(buf));
1317 }
1318 
1319 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1320 {
1321 	/* Hardware does not support an input mode */
1322 	return 0;
1323 }
1324 
1325 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1326 {
1327 	/* Hardware does not support an input mode */
1328 	return -ENOTSUPP;
1329 }
1330 
1331 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1332 					int value)
1333 {
1334 	return 0;
1335 }
1336 
1337 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1338 				  unsigned long config)
1339 {
1340 	struct usb_serial *serial = gpiochip_get_data(gc);
1341 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1342 	enum pin_config_param param = pinconf_to_config_param(config);
1343 
1344 	/* Succeed only if in correct mode (this can't be set at runtime) */
1345 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1346 	    (priv->gpio_mode & BIT(gpio)))
1347 		return 0;
1348 
1349 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1350 	    !(priv->gpio_mode & BIT(gpio)))
1351 		return 0;
1352 
1353 	return -ENOTSUPP;
1354 }
1355 
1356 /*
1357  * This function is for configuring GPIO using shared pins, where other signals
1358  * are made unavailable by configuring the use of GPIO. This is believed to be
1359  * only applicable to the cp2105 at this point, the other devices supported by
1360  * this driver that provide GPIO do so in a way that does not impact other
1361  * signals and are thus expected to have very different initialisation.
1362  */
1363 static int cp2105_shared_gpio_init(struct usb_serial *serial)
1364 {
1365 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1366 	struct cp210x_pin_mode mode;
1367 	struct cp210x_config config;
1368 	u8 intf_num = cp210x_interface_num(serial);
1369 	int result;
1370 
1371 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1372 					  CP210X_GET_DEVICEMODE, &mode,
1373 					  sizeof(mode));
1374 	if (result < 0)
1375 		return result;
1376 
1377 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1378 					  CP210X_GET_PORTCONFIG, &config,
1379 					  sizeof(config));
1380 	if (result < 0)
1381 		return result;
1382 
1383 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1384 	if (intf_num == 0) {
1385 		if (mode.eci == CP210X_PIN_MODE_MODEM)
1386 			return 0;
1387 
1388 		priv->config = config.eci_cfg;
1389 		priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) &
1390 						CP210X_ECI_GPIO_MODE_MASK) >>
1391 						CP210X_ECI_GPIO_MODE_OFFSET);
1392 		priv->gc.ngpio = 2;
1393 	} else if (intf_num == 1) {
1394 		if (mode.sci == CP210X_PIN_MODE_MODEM)
1395 			return 0;
1396 
1397 		priv->config = config.sci_cfg;
1398 		priv->gpio_mode = (u8)((le16_to_cpu(config.gpio_mode) &
1399 						CP210X_SCI_GPIO_MODE_MASK) >>
1400 						CP210X_SCI_GPIO_MODE_OFFSET);
1401 		priv->gc.ngpio = 3;
1402 	} else {
1403 		return -ENODEV;
1404 	}
1405 
1406 	priv->gc.label = "cp210x";
1407 	priv->gc.request = cp210x_gpio_request;
1408 	priv->gc.get_direction = cp210x_gpio_direction_get;
1409 	priv->gc.direction_input = cp210x_gpio_direction_input;
1410 	priv->gc.direction_output = cp210x_gpio_direction_output;
1411 	priv->gc.get = cp210x_gpio_get;
1412 	priv->gc.set = cp210x_gpio_set;
1413 	priv->gc.set_config = cp210x_gpio_set_config;
1414 	priv->gc.owner = THIS_MODULE;
1415 	priv->gc.parent = &serial->interface->dev;
1416 	priv->gc.base = -1;
1417 	priv->gc.can_sleep = true;
1418 
1419 	result = gpiochip_add_data(&priv->gc, serial);
1420 	if (!result)
1421 		priv->gpio_registered = true;
1422 
1423 	return result;
1424 }
1425 
1426 static void cp210x_gpio_remove(struct usb_serial *serial)
1427 {
1428 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1429 
1430 	if (priv->gpio_registered) {
1431 		gpiochip_remove(&priv->gc);
1432 		priv->gpio_registered = false;
1433 	}
1434 }
1435 
1436 #else
1437 
1438 static int cp2105_shared_gpio_init(struct usb_serial *serial)
1439 {
1440 	return 0;
1441 }
1442 
1443 static void cp210x_gpio_remove(struct usb_serial *serial)
1444 {
1445 	/* Nothing to do */
1446 }
1447 
1448 #endif
1449 
1450 static int cp210x_port_probe(struct usb_serial_port *port)
1451 {
1452 	struct usb_serial *serial = port->serial;
1453 	struct cp210x_port_private *port_priv;
1454 	int ret;
1455 
1456 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1457 	if (!port_priv)
1458 		return -ENOMEM;
1459 
1460 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1461 
1462 	usb_set_serial_port_data(port, port_priv);
1463 
1464 	ret = cp210x_detect_swapped_line_ctl(port);
1465 	if (ret) {
1466 		kfree(port_priv);
1467 		return ret;
1468 	}
1469 
1470 	return 0;
1471 }
1472 
1473 static int cp210x_port_remove(struct usb_serial_port *port)
1474 {
1475 	struct cp210x_port_private *port_priv;
1476 
1477 	port_priv = usb_get_serial_port_data(port);
1478 	kfree(port_priv);
1479 
1480 	return 0;
1481 }
1482 
1483 static int cp210x_attach(struct usb_serial *serial)
1484 {
1485 	int result;
1486 	struct cp210x_serial_private *priv;
1487 
1488 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1489 	if (!priv)
1490 		return -ENOMEM;
1491 
1492 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1493 					  CP210X_GET_PARTNUM, &priv->partnum,
1494 					  sizeof(priv->partnum));
1495 	if (result < 0) {
1496 		dev_warn(&serial->interface->dev,
1497 			 "querying part number failed\n");
1498 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1499 	}
1500 
1501 	usb_set_serial_data(serial, priv);
1502 
1503 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1504 		result = cp2105_shared_gpio_init(serial);
1505 		if (result < 0) {
1506 			dev_err(&serial->interface->dev,
1507 				"GPIO initialisation failed, continuing without GPIO support\n");
1508 		}
1509 	}
1510 
1511 	return 0;
1512 }
1513 
1514 static void cp210x_disconnect(struct usb_serial *serial)
1515 {
1516 	cp210x_gpio_remove(serial);
1517 }
1518 
1519 static void cp210x_release(struct usb_serial *serial)
1520 {
1521 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1522 
1523 	cp210x_gpio_remove(serial);
1524 
1525 	kfree(priv);
1526 }
1527 
1528 module_usb_serial_driver(serial_drivers, id_table);
1529 
1530 MODULE_DESCRIPTION(DRIVER_DESC);
1531 MODULE_LICENSE("GPL v2");
1532