xref: /linux/drivers/usb/serial/cp210x.c (revision 4c9f4865f4604744d4f1a43db22ac6ec9dc8e587)
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  * Copyright (C) 2010-2021 Johan Hovold (johan@kernel.org)
7  *
8  * Support to set flow control line levels using TIOCMGET and TIOCMSET
9  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
10  * control thanks to Munir Nassar nassarmu@real-time.com
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/module.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/gpio/driver.h>
23 #include <linux/bitops.h>
24 #include <linux/mutex.h>
25 
26 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
27 
28 /*
29  * Function Prototypes
30  */
31 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
32 static void cp210x_close(struct usb_serial_port *);
33 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
34 							struct ktermios *);
35 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
36 							struct ktermios*);
37 static bool cp210x_tx_empty(struct usb_serial_port *port);
38 static int cp210x_tiocmget(struct tty_struct *);
39 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
40 static int cp210x_tiocmset_port(struct usb_serial_port *port,
41 		unsigned int, unsigned int);
42 static void cp210x_break_ctl(struct tty_struct *, int);
43 static int cp210x_attach(struct usb_serial *);
44 static void cp210x_disconnect(struct usb_serial *);
45 static void cp210x_release(struct usb_serial *);
46 static int cp210x_port_probe(struct usb_serial_port *);
47 static void cp210x_port_remove(struct usb_serial_port *);
48 static void cp210x_dtr_rts(struct usb_serial_port *port, int on);
49 static void cp210x_process_read_urb(struct urb *urb);
50 static void cp210x_enable_event_mode(struct usb_serial_port *port);
51 static void cp210x_disable_event_mode(struct usb_serial_port *port);
52 
53 static const struct usb_device_id id_table[] = {
54 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
55 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
56 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
57 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
58 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
59 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
60 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
61 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
62 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
63 	{ USB_DEVICE(0x0988, 0x0578) }, /* Teraoka AD2000 */
64 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
65 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
66 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
67 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
68 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
69 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
71 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
72 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
73 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
74 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
75 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
76 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
77 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
78 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
79 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
80 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
81 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
82 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
83 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
84 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
85 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
86 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
87 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
88 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
89 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
90 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
91 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
92 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
93 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
94 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
95 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
96 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
97 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
98 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
99 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
100 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
104 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
105 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
106 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
107 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
108 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
109 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
110 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
111 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
112 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
113 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
114 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
115 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
116 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
117 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
118 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
119 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
120 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
121 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
122 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
123 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
124 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
125 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
126 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
127 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
128 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
129 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
130 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
131 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
132 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
133 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
134 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
135 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
136 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
137 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
138 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
139 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
140 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
141 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
142 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
143 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
144 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
145 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
146 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
147 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
148 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
149 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
150 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
151 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
152 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
153 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
154 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
155 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
156 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
157 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
158 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
159 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
160 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
161 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
162 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
163 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
164 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
165 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
166 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
167 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
168 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
169 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
170 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
171 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
172 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
173 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
174 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
175 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
176 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
177 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
178 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
179 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
180 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
181 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
182 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
183 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
184 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
185 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
186 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
187 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
188 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
189 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
190 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
191 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
192 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
193 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
194 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
195 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
196 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
197 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
198 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
199 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
200 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
201 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
202 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
203 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
204 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
205 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
206 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
207 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
208 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
209 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
210 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
211 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
212 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
213 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
214 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
215 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
216 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
217 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
218 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
219 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
220 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
221 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
222 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
227 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
228 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
229 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
230 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
231 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
232 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
233 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
234 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
235 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
236 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
237 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
238 	{ } /* Terminating Entry */
239 };
240 
241 MODULE_DEVICE_TABLE(usb, id_table);
242 
243 struct cp210x_serial_private {
244 #ifdef CONFIG_GPIOLIB
245 	struct gpio_chip	gc;
246 	bool			gpio_registered;
247 	u8			gpio_pushpull;
248 	u8			gpio_altfunc;
249 	u8			gpio_input;
250 #endif
251 	u8			partnum;
252 	speed_t			min_speed;
253 	speed_t			max_speed;
254 	bool			use_actual_rate;
255 };
256 
257 enum cp210x_event_state {
258 	ES_DATA,
259 	ES_ESCAPE,
260 	ES_LSR,
261 	ES_LSR_DATA_0,
262 	ES_LSR_DATA_1,
263 	ES_MSR
264 };
265 
266 struct cp210x_port_private {
267 	u8			bInterfaceNumber;
268 	bool			event_mode;
269 	enum cp210x_event_state event_state;
270 	u8			lsr;
271 
272 	struct mutex		mutex;
273 	bool			crtscts;
274 	bool			dtr;
275 	bool			rts;
276 };
277 
278 static struct usb_serial_driver cp210x_device = {
279 	.driver = {
280 		.owner =	THIS_MODULE,
281 		.name =		"cp210x",
282 	},
283 	.id_table		= id_table,
284 	.num_ports		= 1,
285 	.bulk_in_size		= 256,
286 	.bulk_out_size		= 256,
287 	.open			= cp210x_open,
288 	.close			= cp210x_close,
289 	.break_ctl		= cp210x_break_ctl,
290 	.set_termios		= cp210x_set_termios,
291 	.tx_empty		= cp210x_tx_empty,
292 	.throttle		= usb_serial_generic_throttle,
293 	.unthrottle		= usb_serial_generic_unthrottle,
294 	.tiocmget		= cp210x_tiocmget,
295 	.tiocmset		= cp210x_tiocmset,
296 	.get_icount		= usb_serial_generic_get_icount,
297 	.attach			= cp210x_attach,
298 	.disconnect		= cp210x_disconnect,
299 	.release		= cp210x_release,
300 	.port_probe		= cp210x_port_probe,
301 	.port_remove		= cp210x_port_remove,
302 	.dtr_rts		= cp210x_dtr_rts,
303 	.process_read_urb	= cp210x_process_read_urb,
304 };
305 
306 static struct usb_serial_driver * const serial_drivers[] = {
307 	&cp210x_device, NULL
308 };
309 
310 /* Config request types */
311 #define REQTYPE_HOST_TO_INTERFACE	0x41
312 #define REQTYPE_INTERFACE_TO_HOST	0xc1
313 #define REQTYPE_HOST_TO_DEVICE	0x40
314 #define REQTYPE_DEVICE_TO_HOST	0xc0
315 
316 /* Config request codes */
317 #define CP210X_IFC_ENABLE	0x00
318 #define CP210X_SET_BAUDDIV	0x01
319 #define CP210X_GET_BAUDDIV	0x02
320 #define CP210X_SET_LINE_CTL	0x03
321 #define CP210X_GET_LINE_CTL	0x04
322 #define CP210X_SET_BREAK	0x05
323 #define CP210X_IMM_CHAR		0x06
324 #define CP210X_SET_MHS		0x07
325 #define CP210X_GET_MDMSTS	0x08
326 #define CP210X_SET_XON		0x09
327 #define CP210X_SET_XOFF		0x0A
328 #define CP210X_SET_EVENTMASK	0x0B
329 #define CP210X_GET_EVENTMASK	0x0C
330 #define CP210X_SET_CHAR		0x0D
331 #define CP210X_GET_CHARS	0x0E
332 #define CP210X_GET_PROPS	0x0F
333 #define CP210X_GET_COMM_STATUS	0x10
334 #define CP210X_RESET		0x11
335 #define CP210X_PURGE		0x12
336 #define CP210X_SET_FLOW		0x13
337 #define CP210X_GET_FLOW		0x14
338 #define CP210X_EMBED_EVENTS	0x15
339 #define CP210X_GET_EVENTSTATE	0x16
340 #define CP210X_SET_CHARS	0x19
341 #define CP210X_GET_BAUDRATE	0x1D
342 #define CP210X_SET_BAUDRATE	0x1E
343 #define CP210X_VENDOR_SPECIFIC	0xFF
344 
345 /* CP210X_IFC_ENABLE */
346 #define UART_ENABLE		0x0001
347 #define UART_DISABLE		0x0000
348 
349 /* CP210X_(SET|GET)_BAUDDIV */
350 #define BAUD_RATE_GEN_FREQ	0x384000
351 
352 /* CP210X_(SET|GET)_LINE_CTL */
353 #define BITS_DATA_MASK		0X0f00
354 #define BITS_DATA_5		0X0500
355 #define BITS_DATA_6		0X0600
356 #define BITS_DATA_7		0X0700
357 #define BITS_DATA_8		0X0800
358 #define BITS_DATA_9		0X0900
359 
360 #define BITS_PARITY_MASK	0x00f0
361 #define BITS_PARITY_NONE	0x0000
362 #define BITS_PARITY_ODD		0x0010
363 #define BITS_PARITY_EVEN	0x0020
364 #define BITS_PARITY_MARK	0x0030
365 #define BITS_PARITY_SPACE	0x0040
366 
367 #define BITS_STOP_MASK		0x000f
368 #define BITS_STOP_1		0x0000
369 #define BITS_STOP_1_5		0x0001
370 #define BITS_STOP_2		0x0002
371 
372 /* CP210X_SET_BREAK */
373 #define BREAK_ON		0x0001
374 #define BREAK_OFF		0x0000
375 
376 /* CP210X_(SET_MHS|GET_MDMSTS) */
377 #define CONTROL_DTR		0x0001
378 #define CONTROL_RTS		0x0002
379 #define CONTROL_CTS		0x0010
380 #define CONTROL_DSR		0x0020
381 #define CONTROL_RING		0x0040
382 #define CONTROL_DCD		0x0080
383 #define CONTROL_WRITE_DTR	0x0100
384 #define CONTROL_WRITE_RTS	0x0200
385 
386 /* CP210X_(GET|SET)_CHARS */
387 struct cp210x_special_chars {
388 	u8	bEofChar;
389 	u8	bErrorChar;
390 	u8	bBreakChar;
391 	u8	bEventChar;
392 	u8	bXonChar;
393 	u8	bXoffChar;
394 };
395 
396 /* CP210X_VENDOR_SPECIFIC values */
397 #define CP210X_READ_2NCONFIG	0x000E
398 #define CP210X_READ_LATCH	0x00C2
399 #define CP210X_GET_PARTNUM	0x370B
400 #define CP210X_GET_PORTCONFIG	0x370C
401 #define CP210X_GET_DEVICEMODE	0x3711
402 #define CP210X_WRITE_LATCH	0x37E1
403 
404 /* Part number definitions */
405 #define CP210X_PARTNUM_CP2101	0x01
406 #define CP210X_PARTNUM_CP2102	0x02
407 #define CP210X_PARTNUM_CP2103	0x03
408 #define CP210X_PARTNUM_CP2104	0x04
409 #define CP210X_PARTNUM_CP2105	0x05
410 #define CP210X_PARTNUM_CP2108	0x08
411 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
412 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
413 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
414 #define CP210X_PARTNUM_UNKNOWN	0xFF
415 
416 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
417 struct cp210x_comm_status {
418 	__le32   ulErrors;
419 	__le32   ulHoldReasons;
420 	__le32   ulAmountInInQueue;
421 	__le32   ulAmountInOutQueue;
422 	u8       bEofReceived;
423 	u8       bWaitForImmediate;
424 	u8       bReserved;
425 } __packed;
426 
427 /*
428  * CP210X_PURGE - 16 bits passed in wValue of USB request.
429  * SiLabs app note AN571 gives a strange description of the 4 bits:
430  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
431  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
432  */
433 #define PURGE_ALL		0x000f
434 
435 /* CP210X_EMBED_EVENTS */
436 #define CP210X_ESCCHAR		0xec
437 
438 #define CP210X_LSR_OVERRUN	BIT(1)
439 #define CP210X_LSR_PARITY	BIT(2)
440 #define CP210X_LSR_FRAME	BIT(3)
441 #define CP210X_LSR_BREAK	BIT(4)
442 
443 
444 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
445 struct cp210x_flow_ctl {
446 	__le32	ulControlHandshake;
447 	__le32	ulFlowReplace;
448 	__le32	ulXonLimit;
449 	__le32	ulXoffLimit;
450 };
451 
452 /* cp210x_flow_ctl::ulControlHandshake */
453 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
454 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
455 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
456 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
457 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
458 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
459 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
460 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
461 
462 /* cp210x_flow_ctl::ulFlowReplace */
463 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
464 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
465 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
466 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
467 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
468 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
469 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
470 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
471 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
472 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
473 
474 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
475 struct cp210x_pin_mode {
476 	u8	eci;
477 	u8	sci;
478 };
479 
480 #define CP210X_PIN_MODE_MODEM		0
481 #define CP210X_PIN_MODE_GPIO		BIT(0)
482 
483 /*
484  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
485  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
486  */
487 struct cp210x_dual_port_config {
488 	__le16	gpio_mode;
489 	u8	__pad0[2];
490 	__le16	reset_state;
491 	u8	__pad1[4];
492 	__le16	suspend_state;
493 	u8	sci_cfg;
494 	u8	eci_cfg;
495 	u8	device_cfg;
496 } __packed;
497 
498 /*
499  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
500  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
501  */
502 struct cp210x_single_port_config {
503 	__le16	gpio_mode;
504 	u8	__pad0[2];
505 	__le16	reset_state;
506 	u8	__pad1[4];
507 	__le16	suspend_state;
508 	u8	device_cfg;
509 } __packed;
510 
511 /* GPIO modes */
512 #define CP210X_SCI_GPIO_MODE_OFFSET	9
513 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
514 
515 #define CP210X_ECI_GPIO_MODE_OFFSET	2
516 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
517 
518 #define CP210X_GPIO_MODE_OFFSET		8
519 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
520 
521 /* CP2105 port configuration values */
522 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
523 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
524 #define CP2105_GPIO1_RS485_MODE		BIT(2)
525 
526 /* CP2104 port configuration values */
527 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
528 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
529 #define CP2104_GPIO2_RS485_MODE		BIT(2)
530 
531 /* CP2102N configuration array indices */
532 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
533 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
534 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
535 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
536 
537 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
538 struct cp210x_gpio_write {
539 	u8	mask;
540 	u8	state;
541 };
542 
543 /*
544  * Helper to get interface number when we only have struct usb_serial.
545  */
546 static u8 cp210x_interface_num(struct usb_serial *serial)
547 {
548 	struct usb_host_interface *cur_altsetting;
549 
550 	cur_altsetting = serial->interface->cur_altsetting;
551 
552 	return cur_altsetting->desc.bInterfaceNumber;
553 }
554 
555 /*
556  * Reads a variable-sized block of CP210X_ registers, identified by req.
557  * Returns data into buf in native USB byte order.
558  */
559 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
560 		void *buf, int bufsize)
561 {
562 	struct usb_serial *serial = port->serial;
563 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
564 	void *dmabuf;
565 	int result;
566 
567 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
568 	if (!dmabuf)
569 		return -ENOMEM;
570 
571 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
572 			req, REQTYPE_INTERFACE_TO_HOST, 0,
573 			port_priv->bInterfaceNumber, dmabuf, bufsize,
574 			USB_CTRL_SET_TIMEOUT);
575 	if (result == bufsize) {
576 		memcpy(buf, dmabuf, bufsize);
577 		result = 0;
578 	} else {
579 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
580 				req, bufsize, result);
581 		if (result >= 0)
582 			result = -EIO;
583 	}
584 
585 	kfree(dmabuf);
586 
587 	return result;
588 }
589 
590 /*
591  * Reads any 8-bit CP210X_ register identified by req.
592  */
593 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
594 {
595 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
596 }
597 
598 /*
599  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
600  * Returns data into buf in native USB byte order.
601  */
602 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
603 				    void *buf, int bufsize)
604 {
605 	void *dmabuf;
606 	int result;
607 
608 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
609 	if (!dmabuf)
610 		return -ENOMEM;
611 
612 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
613 				 CP210X_VENDOR_SPECIFIC, type, val,
614 				 cp210x_interface_num(serial), dmabuf, bufsize,
615 				 USB_CTRL_GET_TIMEOUT);
616 	if (result == bufsize) {
617 		memcpy(buf, dmabuf, bufsize);
618 		result = 0;
619 	} else {
620 		dev_err(&serial->interface->dev,
621 			"failed to get vendor val 0x%04x size %d: %d\n", val,
622 			bufsize, result);
623 		if (result >= 0)
624 			result = -EIO;
625 	}
626 
627 	kfree(dmabuf);
628 
629 	return result;
630 }
631 
632 /*
633  * Writes any 16-bit CP210X_ register (req) whose value is passed
634  * entirely in the wValue field of the USB request.
635  */
636 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
637 {
638 	struct usb_serial *serial = port->serial;
639 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
640 	int result;
641 
642 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
643 			req, REQTYPE_HOST_TO_INTERFACE, val,
644 			port_priv->bInterfaceNumber, NULL, 0,
645 			USB_CTRL_SET_TIMEOUT);
646 	if (result < 0) {
647 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
648 				req, result);
649 	}
650 
651 	return result;
652 }
653 
654 /*
655  * Writes a variable-sized block of CP210X_ registers, identified by req.
656  * Data in buf must be in native USB byte order.
657  */
658 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
659 		void *buf, int bufsize)
660 {
661 	struct usb_serial *serial = port->serial;
662 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
663 	void *dmabuf;
664 	int result;
665 
666 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
667 	if (!dmabuf)
668 		return -ENOMEM;
669 
670 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
671 			req, REQTYPE_HOST_TO_INTERFACE, 0,
672 			port_priv->bInterfaceNumber, dmabuf, bufsize,
673 			USB_CTRL_SET_TIMEOUT);
674 
675 	kfree(dmabuf);
676 
677 	if (result < 0) {
678 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
679 				req, bufsize, result);
680 		return result;
681 	}
682 
683 	return 0;
684 }
685 
686 /*
687  * Writes any 32-bit CP210X_ register identified by req.
688  */
689 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
690 {
691 	__le32 le32_val;
692 
693 	le32_val = cpu_to_le32(val);
694 
695 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
696 }
697 
698 #ifdef CONFIG_GPIOLIB
699 /*
700  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
701  * Data in buf must be in native USB byte order.
702  */
703 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
704 				     u16 val, void *buf, int bufsize)
705 {
706 	void *dmabuf;
707 	int result;
708 
709 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
710 	if (!dmabuf)
711 		return -ENOMEM;
712 
713 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
714 				 CP210X_VENDOR_SPECIFIC, type, val,
715 				 cp210x_interface_num(serial), dmabuf, bufsize,
716 				 USB_CTRL_SET_TIMEOUT);
717 
718 	kfree(dmabuf);
719 
720 	if (result < 0) {
721 		dev_err(&serial->interface->dev,
722 			"failed to set vendor val 0x%04x size %d: %d\n", val,
723 			bufsize, result);
724 		return result;
725 	}
726 
727 	return 0;
728 }
729 #endif
730 
731 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
732 {
733 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
734 	int result;
735 
736 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
737 	if (result) {
738 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
739 		return result;
740 	}
741 
742 	if (tty)
743 		cp210x_set_termios(tty, port, NULL);
744 
745 	result = usb_serial_generic_open(tty, port);
746 	if (result)
747 		goto err_disable;
748 
749 	return 0;
750 
751 err_disable:
752 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
753 	port_priv->event_mode = false;
754 
755 	return result;
756 }
757 
758 static void cp210x_close(struct usb_serial_port *port)
759 {
760 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
761 
762 	usb_serial_generic_close(port);
763 
764 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
765 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
766 
767 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
768 
769 	/* Disabling the interface disables event-insertion mode. */
770 	port_priv->event_mode = false;
771 }
772 
773 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
774 {
775 	if (lsr & CP210X_LSR_BREAK) {
776 		port->icount.brk++;
777 		*flag = TTY_BREAK;
778 	} else if (lsr & CP210X_LSR_PARITY) {
779 		port->icount.parity++;
780 		*flag = TTY_PARITY;
781 	} else if (lsr & CP210X_LSR_FRAME) {
782 		port->icount.frame++;
783 		*flag = TTY_FRAME;
784 	}
785 
786 	if (lsr & CP210X_LSR_OVERRUN) {
787 		port->icount.overrun++;
788 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
789 	}
790 }
791 
792 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
793 {
794 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
795 
796 	switch (port_priv->event_state) {
797 	case ES_DATA:
798 		if (*ch == CP210X_ESCCHAR) {
799 			port_priv->event_state = ES_ESCAPE;
800 			break;
801 		}
802 		return false;
803 	case ES_ESCAPE:
804 		switch (*ch) {
805 		case 0:
806 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
807 			*ch = CP210X_ESCCHAR;
808 			port_priv->event_state = ES_DATA;
809 			return false;
810 		case 1:
811 			port_priv->event_state = ES_LSR_DATA_0;
812 			break;
813 		case 2:
814 			port_priv->event_state = ES_LSR;
815 			break;
816 		case 3:
817 			port_priv->event_state = ES_MSR;
818 			break;
819 		default:
820 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
821 			port_priv->event_state = ES_DATA;
822 			break;
823 		}
824 		break;
825 	case ES_LSR_DATA_0:
826 		port_priv->lsr = *ch;
827 		port_priv->event_state = ES_LSR_DATA_1;
828 		break;
829 	case ES_LSR_DATA_1:
830 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
831 				__func__, port_priv->lsr, *ch);
832 		cp210x_process_lsr(port, port_priv->lsr, flag);
833 		port_priv->event_state = ES_DATA;
834 		return false;
835 	case ES_LSR:
836 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
837 		port_priv->lsr = *ch;
838 		cp210x_process_lsr(port, port_priv->lsr, flag);
839 		port_priv->event_state = ES_DATA;
840 		break;
841 	case ES_MSR:
842 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
843 		/* unimplemented */
844 		port_priv->event_state = ES_DATA;
845 		break;
846 	}
847 
848 	return true;
849 }
850 
851 static void cp210x_process_read_urb(struct urb *urb)
852 {
853 	struct usb_serial_port *port = urb->context;
854 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
855 	unsigned char *ch = urb->transfer_buffer;
856 	char flag;
857 	int i;
858 
859 	if (!urb->actual_length)
860 		return;
861 
862 	if (port_priv->event_mode) {
863 		for (i = 0; i < urb->actual_length; i++, ch++) {
864 			flag = TTY_NORMAL;
865 
866 			if (cp210x_process_char(port, ch, &flag))
867 				continue;
868 
869 			tty_insert_flip_char(&port->port, *ch, flag);
870 		}
871 	} else {
872 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
873 	}
874 	tty_flip_buffer_push(&port->port);
875 }
876 
877 /*
878  * Read how many bytes are waiting in the TX queue.
879  */
880 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
881 		u32 *count)
882 {
883 	struct usb_serial *serial = port->serial;
884 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
885 	struct cp210x_comm_status *sts;
886 	int result;
887 
888 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
889 	if (!sts)
890 		return -ENOMEM;
891 
892 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
893 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
894 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
895 			USB_CTRL_GET_TIMEOUT);
896 	if (result == sizeof(*sts)) {
897 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
898 		result = 0;
899 	} else {
900 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
901 		if (result >= 0)
902 			result = -EIO;
903 	}
904 
905 	kfree(sts);
906 
907 	return result;
908 }
909 
910 static bool cp210x_tx_empty(struct usb_serial_port *port)
911 {
912 	int err;
913 	u32 count;
914 
915 	err = cp210x_get_tx_queue_byte_count(port, &count);
916 	if (err)
917 		return true;
918 
919 	return !count;
920 }
921 
922 struct cp210x_rate {
923 	speed_t rate;
924 	speed_t high;
925 };
926 
927 static const struct cp210x_rate cp210x_an205_table1[] = {
928 	{ 300, 300 },
929 	{ 600, 600 },
930 	{ 1200, 1200 },
931 	{ 1800, 1800 },
932 	{ 2400, 2400 },
933 	{ 4000, 4000 },
934 	{ 4800, 4803 },
935 	{ 7200, 7207 },
936 	{ 9600, 9612 },
937 	{ 14400, 14428 },
938 	{ 16000, 16062 },
939 	{ 19200, 19250 },
940 	{ 28800, 28912 },
941 	{ 38400, 38601 },
942 	{ 51200, 51558 },
943 	{ 56000, 56280 },
944 	{ 57600, 58053 },
945 	{ 64000, 64111 },
946 	{ 76800, 77608 },
947 	{ 115200, 117028 },
948 	{ 128000, 129347 },
949 	{ 153600, 156868 },
950 	{ 230400, 237832 },
951 	{ 250000, 254234 },
952 	{ 256000, 273066 },
953 	{ 460800, 491520 },
954 	{ 500000, 567138 },
955 	{ 576000, 670254 },
956 	{ 921600, UINT_MAX }
957 };
958 
959 /*
960  * Quantises the baud rate as per AN205 Table 1
961  */
962 static speed_t cp210x_get_an205_rate(speed_t baud)
963 {
964 	int i;
965 
966 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
967 		if (baud <= cp210x_an205_table1[i].high)
968 			break;
969 	}
970 
971 	return cp210x_an205_table1[i].rate;
972 }
973 
974 static speed_t cp210x_get_actual_rate(speed_t baud)
975 {
976 	unsigned int prescale = 1;
977 	unsigned int div;
978 
979 	if (baud <= 365)
980 		prescale = 4;
981 
982 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
983 	baud = 48000000 / (2 * prescale * div);
984 
985 	return baud;
986 }
987 
988 /*
989  * CP2101 supports the following baud rates:
990  *
991  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
992  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
993  *
994  * CP2102 and CP2103 support the following additional rates:
995  *
996  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
997  *	576000
998  *
999  * The device will map a requested rate to a supported one, but the result
1000  * of requests for rates greater than 1053257 is undefined (see AN205).
1001  *
1002  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1003  * respectively, with an error less than 1%. The actual rates are determined
1004  * by
1005  *
1006  *	div = round(freq / (2 x prescale x request))
1007  *	actual = freq / (2 x prescale x div)
1008  *
1009  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1010  * or 1 otherwise.
1011  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1012  * otherwise.
1013  */
1014 static void cp210x_change_speed(struct tty_struct *tty,
1015 		struct usb_serial_port *port, struct ktermios *old_termios)
1016 {
1017 	struct usb_serial *serial = port->serial;
1018 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1019 	u32 baud;
1020 
1021 	/*
1022 	 * This maps the requested rate to the actual rate, a valid rate on
1023 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1024 	 *
1025 	 * NOTE: B0 is not implemented.
1026 	 */
1027 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1028 
1029 	if (priv->use_actual_rate)
1030 		baud = cp210x_get_actual_rate(baud);
1031 	else if (baud < 1000000)
1032 		baud = cp210x_get_an205_rate(baud);
1033 
1034 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1035 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1036 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1037 		if (old_termios)
1038 			baud = old_termios->c_ospeed;
1039 		else
1040 			baud = 9600;
1041 	}
1042 
1043 	tty_encode_baud_rate(tty, baud, baud);
1044 }
1045 
1046 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1047 {
1048 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1049 	int ret;
1050 
1051 	if (port_priv->event_mode)
1052 		return;
1053 
1054 	port_priv->event_state = ES_DATA;
1055 	port_priv->event_mode = true;
1056 
1057 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1058 	if (ret) {
1059 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1060 		port_priv->event_mode = false;
1061 	}
1062 }
1063 
1064 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1065 {
1066 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1067 	int ret;
1068 
1069 	if (!port_priv->event_mode)
1070 		return;
1071 
1072 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1073 	if (ret) {
1074 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1075 		return;
1076 	}
1077 
1078 	port_priv->event_mode = false;
1079 }
1080 
1081 static int cp210x_set_chars(struct usb_serial_port *port,
1082 		struct cp210x_special_chars *chars)
1083 {
1084 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1085 	struct usb_serial *serial = port->serial;
1086 	void *dmabuf;
1087 	int result;
1088 
1089 	dmabuf = kmemdup(chars, sizeof(*chars), GFP_KERNEL);
1090 	if (!dmabuf)
1091 		return -ENOMEM;
1092 
1093 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1094 				CP210X_SET_CHARS, REQTYPE_HOST_TO_INTERFACE, 0,
1095 				port_priv->bInterfaceNumber,
1096 				dmabuf, sizeof(*chars), USB_CTRL_SET_TIMEOUT);
1097 
1098 	kfree(dmabuf);
1099 
1100 	if (result < 0) {
1101 		dev_err(&port->dev, "failed to set special chars: %d\n", result);
1102 		return result;
1103 	}
1104 
1105 	return 0;
1106 }
1107 
1108 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1109 {
1110 	bool iflag_change, cc_change;
1111 
1112 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1113 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1114 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1115 
1116 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1117 }
1118 
1119 static void cp210x_set_flow_control(struct tty_struct *tty,
1120 		struct usb_serial_port *port, struct ktermios *old_termios)
1121 {
1122 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1123 	struct cp210x_special_chars chars;
1124 	struct cp210x_flow_ctl flow_ctl;
1125 	u32 flow_repl;
1126 	u32 ctl_hs;
1127 	int ret;
1128 
1129 	if (old_termios &&
1130 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1131 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1132 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1133 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1134 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1135 		return;
1136 	}
1137 
1138 	if (I_IXON(tty) || I_IXOFF(tty)) {
1139 		memset(&chars, 0, sizeof(chars));
1140 
1141 		chars.bXonChar = START_CHAR(tty);
1142 		chars.bXoffChar = STOP_CHAR(tty);
1143 
1144 		ret = cp210x_set_chars(port, &chars);
1145 		if (ret)
1146 			return;
1147 	}
1148 
1149 	mutex_lock(&port_priv->mutex);
1150 
1151 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1152 			sizeof(flow_ctl));
1153 	if (ret)
1154 		goto out_unlock;
1155 
1156 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1157 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
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 	if (port_priv->dtr)
1164 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1165 	else
1166 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1167 
1168 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1169 	if (C_CRTSCTS(tty)) {
1170 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1171 		if (port_priv->rts)
1172 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1173 		else
1174 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1175 		port_priv->crtscts = true;
1176 	} else {
1177 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1178 		if (port_priv->rts)
1179 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1180 		else
1181 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1182 		port_priv->crtscts = false;
1183 	}
1184 
1185 	if (I_IXOFF(tty))
1186 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1187 	else
1188 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1189 
1190 	if (I_IXON(tty))
1191 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1192 	else
1193 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1194 
1195 	flow_ctl.ulXonLimit = cpu_to_le32(128);
1196 	flow_ctl.ulXoffLimit = cpu_to_le32(128);
1197 
1198 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1199 			ctl_hs, flow_repl);
1200 
1201 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1202 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1203 
1204 	cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1205 			sizeof(flow_ctl));
1206 out_unlock:
1207 	mutex_unlock(&port_priv->mutex);
1208 }
1209 
1210 static void cp210x_set_termios(struct tty_struct *tty,
1211 		struct usb_serial_port *port, struct ktermios *old_termios)
1212 {
1213 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1214 	u16 bits;
1215 	int ret;
1216 
1217 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1218 		return;
1219 
1220 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1221 		cp210x_change_speed(tty, port, old_termios);
1222 
1223 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1224 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1225 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1226 		tty->termios.c_cflag |= CS8;
1227 	}
1228 
1229 	bits = 0;
1230 
1231 	switch (C_CSIZE(tty)) {
1232 	case CS5:
1233 		bits |= BITS_DATA_5;
1234 		break;
1235 	case CS6:
1236 		bits |= BITS_DATA_6;
1237 		break;
1238 	case CS7:
1239 		bits |= BITS_DATA_7;
1240 		break;
1241 	case CS8:
1242 	default:
1243 		bits |= BITS_DATA_8;
1244 		break;
1245 	}
1246 
1247 	if (C_PARENB(tty)) {
1248 		if (C_CMSPAR(tty)) {
1249 			if (C_PARODD(tty))
1250 				bits |= BITS_PARITY_MARK;
1251 			else
1252 				bits |= BITS_PARITY_SPACE;
1253 		} else {
1254 			if (C_PARODD(tty))
1255 				bits |= BITS_PARITY_ODD;
1256 			else
1257 				bits |= BITS_PARITY_EVEN;
1258 		}
1259 	}
1260 
1261 	if (C_CSTOPB(tty))
1262 		bits |= BITS_STOP_2;
1263 	else
1264 		bits |= BITS_STOP_1;
1265 
1266 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1267 	if (ret)
1268 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1269 
1270 	cp210x_set_flow_control(tty, port, old_termios);
1271 
1272 	/*
1273 	 * Enable event-insertion mode only if input parity checking is
1274 	 * enabled for now.
1275 	 */
1276 	if (I_INPCK(tty))
1277 		cp210x_enable_event_mode(port);
1278 	else
1279 		cp210x_disable_event_mode(port);
1280 }
1281 
1282 static int cp210x_tiocmset(struct tty_struct *tty,
1283 		unsigned int set, unsigned int clear)
1284 {
1285 	struct usb_serial_port *port = tty->driver_data;
1286 	return cp210x_tiocmset_port(port, set, clear);
1287 }
1288 
1289 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1290 		unsigned int set, unsigned int clear)
1291 {
1292 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1293 	struct cp210x_flow_ctl flow_ctl;
1294 	u32 ctl_hs, flow_repl;
1295 	u16 control = 0;
1296 	int ret;
1297 
1298 	mutex_lock(&port_priv->mutex);
1299 
1300 	if (set & TIOCM_RTS) {
1301 		port_priv->rts = true;
1302 		control |= CONTROL_RTS;
1303 		control |= CONTROL_WRITE_RTS;
1304 	}
1305 	if (set & TIOCM_DTR) {
1306 		port_priv->dtr = true;
1307 		control |= CONTROL_DTR;
1308 		control |= CONTROL_WRITE_DTR;
1309 	}
1310 	if (clear & TIOCM_RTS) {
1311 		port_priv->rts = false;
1312 		control &= ~CONTROL_RTS;
1313 		control |= CONTROL_WRITE_RTS;
1314 	}
1315 	if (clear & TIOCM_DTR) {
1316 		port_priv->dtr = false;
1317 		control &= ~CONTROL_DTR;
1318 		control |= CONTROL_WRITE_DTR;
1319 	}
1320 
1321 	/*
1322 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1323 	 * flow control is enabled.
1324 	 */
1325 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1326 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1327 				sizeof(flow_ctl));
1328 		if (ret)
1329 			goto out_unlock;
1330 
1331 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1332 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1333 
1334 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1335 		if (port_priv->dtr)
1336 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1337 		else
1338 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1339 
1340 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1341 		if (port_priv->rts)
1342 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1343 		else
1344 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1345 
1346 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1347 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1348 
1349 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1350 				__func__, ctl_hs, flow_repl);
1351 
1352 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1353 				sizeof(flow_ctl));
1354 	} else {
1355 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1356 
1357 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1358 	}
1359 out_unlock:
1360 	mutex_unlock(&port_priv->mutex);
1361 
1362 	return ret;
1363 }
1364 
1365 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1366 {
1367 	if (on)
1368 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1369 	else
1370 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1371 }
1372 
1373 static int cp210x_tiocmget(struct tty_struct *tty)
1374 {
1375 	struct usb_serial_port *port = tty->driver_data;
1376 	u8 control;
1377 	int result;
1378 
1379 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1380 	if (result)
1381 		return result;
1382 
1383 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1384 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1385 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1386 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1387 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1388 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1389 
1390 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1391 
1392 	return result;
1393 }
1394 
1395 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1396 {
1397 	struct usb_serial_port *port = tty->driver_data;
1398 	u16 state;
1399 
1400 	if (break_state == 0)
1401 		state = BREAK_OFF;
1402 	else
1403 		state = BREAK_ON;
1404 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1405 		state == BREAK_OFF ? "off" : "on");
1406 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1407 }
1408 
1409 #ifdef CONFIG_GPIOLIB
1410 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1411 {
1412 	struct usb_serial *serial = gpiochip_get_data(gc);
1413 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1414 
1415 	if (priv->gpio_altfunc & BIT(offset))
1416 		return -ENODEV;
1417 
1418 	return 0;
1419 }
1420 
1421 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1422 {
1423 	struct usb_serial *serial = gpiochip_get_data(gc);
1424 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1425 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1426 	int result;
1427 	u8 buf;
1428 
1429 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1430 		req_type = REQTYPE_INTERFACE_TO_HOST;
1431 
1432 	result = usb_autopm_get_interface(serial->interface);
1433 	if (result)
1434 		return result;
1435 
1436 	result = cp210x_read_vendor_block(serial, req_type,
1437 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1438 	usb_autopm_put_interface(serial->interface);
1439 	if (result < 0)
1440 		return result;
1441 
1442 	return !!(buf & BIT(gpio));
1443 }
1444 
1445 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1446 {
1447 	struct usb_serial *serial = gpiochip_get_data(gc);
1448 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1449 	struct cp210x_gpio_write buf;
1450 	int result;
1451 
1452 	if (value == 1)
1453 		buf.state = BIT(gpio);
1454 	else
1455 		buf.state = 0;
1456 
1457 	buf.mask = BIT(gpio);
1458 
1459 	result = usb_autopm_get_interface(serial->interface);
1460 	if (result)
1461 		goto out;
1462 
1463 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1464 		result = cp210x_write_vendor_block(serial,
1465 						   REQTYPE_HOST_TO_INTERFACE,
1466 						   CP210X_WRITE_LATCH, &buf,
1467 						   sizeof(buf));
1468 	} else {
1469 		u16 wIndex = buf.state << 8 | buf.mask;
1470 
1471 		result = usb_control_msg(serial->dev,
1472 					 usb_sndctrlpipe(serial->dev, 0),
1473 					 CP210X_VENDOR_SPECIFIC,
1474 					 REQTYPE_HOST_TO_DEVICE,
1475 					 CP210X_WRITE_LATCH,
1476 					 wIndex,
1477 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1478 	}
1479 
1480 	usb_autopm_put_interface(serial->interface);
1481 out:
1482 	if (result < 0) {
1483 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1484 				result);
1485 	}
1486 }
1487 
1488 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1489 {
1490 	struct usb_serial *serial = gpiochip_get_data(gc);
1491 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1492 
1493 	return priv->gpio_input & BIT(gpio);
1494 }
1495 
1496 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1497 {
1498 	struct usb_serial *serial = gpiochip_get_data(gc);
1499 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1500 
1501 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1502 		/* hardware does not support an input mode */
1503 		return -ENOTSUPP;
1504 	}
1505 
1506 	/* push-pull pins cannot be changed to be inputs */
1507 	if (priv->gpio_pushpull & BIT(gpio))
1508 		return -EINVAL;
1509 
1510 	/* make sure to release pin if it is being driven low */
1511 	cp210x_gpio_set(gc, gpio, 1);
1512 
1513 	priv->gpio_input |= BIT(gpio);
1514 
1515 	return 0;
1516 }
1517 
1518 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1519 					int value)
1520 {
1521 	struct usb_serial *serial = gpiochip_get_data(gc);
1522 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1523 
1524 	priv->gpio_input &= ~BIT(gpio);
1525 	cp210x_gpio_set(gc, gpio, value);
1526 
1527 	return 0;
1528 }
1529 
1530 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1531 				  unsigned long config)
1532 {
1533 	struct usb_serial *serial = gpiochip_get_data(gc);
1534 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1535 	enum pin_config_param param = pinconf_to_config_param(config);
1536 
1537 	/* Succeed only if in correct mode (this can't be set at runtime) */
1538 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1539 	    (priv->gpio_pushpull & BIT(gpio)))
1540 		return 0;
1541 
1542 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1543 	    !(priv->gpio_pushpull & BIT(gpio)))
1544 		return 0;
1545 
1546 	return -ENOTSUPP;
1547 }
1548 
1549 /*
1550  * This function is for configuring GPIO using shared pins, where other signals
1551  * are made unavailable by configuring the use of GPIO. This is believed to be
1552  * only applicable to the cp2105 at this point, the other devices supported by
1553  * this driver that provide GPIO do so in a way that does not impact other
1554  * signals and are thus expected to have very different initialisation.
1555  */
1556 static int cp2105_gpioconf_init(struct usb_serial *serial)
1557 {
1558 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1559 	struct cp210x_pin_mode mode;
1560 	struct cp210x_dual_port_config config;
1561 	u8 intf_num = cp210x_interface_num(serial);
1562 	u8 iface_config;
1563 	int result;
1564 
1565 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1566 					  CP210X_GET_DEVICEMODE, &mode,
1567 					  sizeof(mode));
1568 	if (result < 0)
1569 		return result;
1570 
1571 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1572 					  CP210X_GET_PORTCONFIG, &config,
1573 					  sizeof(config));
1574 	if (result < 0)
1575 		return result;
1576 
1577 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1578 	if (intf_num == 0) {
1579 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1580 			/* mark all GPIOs of this interface as reserved */
1581 			priv->gpio_altfunc = 0xff;
1582 			return 0;
1583 		}
1584 
1585 		iface_config = config.eci_cfg;
1586 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1587 						CP210X_ECI_GPIO_MODE_MASK) >>
1588 						CP210X_ECI_GPIO_MODE_OFFSET);
1589 		priv->gc.ngpio = 2;
1590 	} else if (intf_num == 1) {
1591 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1592 			/* mark all GPIOs of this interface as reserved */
1593 			priv->gpio_altfunc = 0xff;
1594 			return 0;
1595 		}
1596 
1597 		iface_config = config.sci_cfg;
1598 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1599 						CP210X_SCI_GPIO_MODE_MASK) >>
1600 						CP210X_SCI_GPIO_MODE_OFFSET);
1601 		priv->gc.ngpio = 3;
1602 	} else {
1603 		return -ENODEV;
1604 	}
1605 
1606 	/* mark all pins which are not in GPIO mode */
1607 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1608 		priv->gpio_altfunc |= BIT(0);
1609 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1610 			CP2105_GPIO1_RS485_MODE))
1611 		priv->gpio_altfunc |= BIT(1);
1612 
1613 	/* driver implementation for CP2105 only supports outputs */
1614 	priv->gpio_input = 0;
1615 
1616 	return 0;
1617 }
1618 
1619 static int cp2104_gpioconf_init(struct usb_serial *serial)
1620 {
1621 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1622 	struct cp210x_single_port_config config;
1623 	u8 iface_config;
1624 	u8 gpio_latch;
1625 	int result;
1626 	u8 i;
1627 
1628 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1629 					  CP210X_GET_PORTCONFIG, &config,
1630 					  sizeof(config));
1631 	if (result < 0)
1632 		return result;
1633 
1634 	priv->gc.ngpio = 4;
1635 
1636 	iface_config = config.device_cfg;
1637 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1638 					CP210X_GPIO_MODE_MASK) >>
1639 					CP210X_GPIO_MODE_OFFSET);
1640 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1641 					CP210X_GPIO_MODE_MASK) >>
1642 					CP210X_GPIO_MODE_OFFSET);
1643 
1644 	/* mark all pins which are not in GPIO mode */
1645 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1646 		priv->gpio_altfunc |= BIT(0);
1647 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1648 		priv->gpio_altfunc |= BIT(1);
1649 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1650 		priv->gpio_altfunc |= BIT(2);
1651 
1652 	/*
1653 	 * Like CP2102N, CP2104 has also no strict input and output pin
1654 	 * modes.
1655 	 * Do the same input mode emulation as CP2102N.
1656 	 */
1657 	for (i = 0; i < priv->gc.ngpio; ++i) {
1658 		/*
1659 		 * Set direction to "input" iff pin is open-drain and reset
1660 		 * value is 1.
1661 		 */
1662 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1663 			priv->gpio_input |= BIT(i);
1664 	}
1665 
1666 	return 0;
1667 }
1668 
1669 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1670 {
1671 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1672 	const u16 config_size = 0x02a6;
1673 	u8 gpio_rst_latch;
1674 	u8 config_version;
1675 	u8 gpio_pushpull;
1676 	u8 *config_buf;
1677 	u8 gpio_latch;
1678 	u8 gpio_ctrl;
1679 	int result;
1680 	u8 i;
1681 
1682 	/*
1683 	 * Retrieve device configuration from the device.
1684 	 * The array received contains all customization settings done at the
1685 	 * factory/manufacturer. Format of the array is documented at the
1686 	 * time of writing at:
1687 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1688 	 */
1689 	config_buf = kmalloc(config_size, GFP_KERNEL);
1690 	if (!config_buf)
1691 		return -ENOMEM;
1692 
1693 	result = cp210x_read_vendor_block(serial,
1694 					  REQTYPE_DEVICE_TO_HOST,
1695 					  CP210X_READ_2NCONFIG,
1696 					  config_buf,
1697 					  config_size);
1698 	if (result < 0) {
1699 		kfree(config_buf);
1700 		return result;
1701 	}
1702 
1703 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1704 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1705 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1706 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1707 
1708 	kfree(config_buf);
1709 
1710 	/* Make sure this is a config format we understand. */
1711 	if (config_version != 0x01)
1712 		return -ENOTSUPP;
1713 
1714 	priv->gc.ngpio = 4;
1715 
1716 	/*
1717 	 * Get default pin states after reset. Needed so we can determine
1718 	 * the direction of an open-drain pin.
1719 	 */
1720 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1721 
1722 	/* 0 indicates open-drain mode, 1 is push-pull */
1723 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1724 
1725 	/* 0 indicates GPIO mode, 1 is alternate function */
1726 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1727 
1728 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1729 		/*
1730 		 * For the QFN28 package, GPIO4-6 are controlled by
1731 		 * the low three bits of the mode/latch fields.
1732 		 * Contrary to the document linked above, the bits for
1733 		 * the SUSPEND pins are elsewhere.  No alternate
1734 		 * function is available for these pins.
1735 		 */
1736 		priv->gc.ngpio = 7;
1737 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1738 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1739 	}
1740 
1741 	/*
1742 	 * The CP2102N does not strictly has input and output pin modes,
1743 	 * it only knows open-drain and push-pull modes which is set at
1744 	 * factory. An open-drain pin can function both as an
1745 	 * input or an output. We emulate input mode for open-drain pins
1746 	 * by making sure they are not driven low, and we do not allow
1747 	 * push-pull pins to be set as an input.
1748 	 */
1749 	for (i = 0; i < priv->gc.ngpio; ++i) {
1750 		/*
1751 		 * Set direction to "input" iff pin is open-drain and reset
1752 		 * value is 1.
1753 		 */
1754 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1755 			priv->gpio_input |= BIT(i);
1756 	}
1757 
1758 	return 0;
1759 }
1760 
1761 static int cp210x_gpio_init(struct usb_serial *serial)
1762 {
1763 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1764 	int result;
1765 
1766 	switch (priv->partnum) {
1767 	case CP210X_PARTNUM_CP2104:
1768 		result = cp2104_gpioconf_init(serial);
1769 		break;
1770 	case CP210X_PARTNUM_CP2105:
1771 		result = cp2105_gpioconf_init(serial);
1772 		break;
1773 	case CP210X_PARTNUM_CP2102N_QFN28:
1774 	case CP210X_PARTNUM_CP2102N_QFN24:
1775 	case CP210X_PARTNUM_CP2102N_QFN20:
1776 		result = cp2102n_gpioconf_init(serial);
1777 		break;
1778 	default:
1779 		return 0;
1780 	}
1781 
1782 	if (result < 0)
1783 		return result;
1784 
1785 	priv->gc.label = "cp210x";
1786 	priv->gc.request = cp210x_gpio_request;
1787 	priv->gc.get_direction = cp210x_gpio_direction_get;
1788 	priv->gc.direction_input = cp210x_gpio_direction_input;
1789 	priv->gc.direction_output = cp210x_gpio_direction_output;
1790 	priv->gc.get = cp210x_gpio_get;
1791 	priv->gc.set = cp210x_gpio_set;
1792 	priv->gc.set_config = cp210x_gpio_set_config;
1793 	priv->gc.owner = THIS_MODULE;
1794 	priv->gc.parent = &serial->interface->dev;
1795 	priv->gc.base = -1;
1796 	priv->gc.can_sleep = true;
1797 
1798 	result = gpiochip_add_data(&priv->gc, serial);
1799 	if (!result)
1800 		priv->gpio_registered = true;
1801 
1802 	return result;
1803 }
1804 
1805 static void cp210x_gpio_remove(struct usb_serial *serial)
1806 {
1807 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1808 
1809 	if (priv->gpio_registered) {
1810 		gpiochip_remove(&priv->gc);
1811 		priv->gpio_registered = false;
1812 	}
1813 }
1814 
1815 #else
1816 
1817 static int cp210x_gpio_init(struct usb_serial *serial)
1818 {
1819 	return 0;
1820 }
1821 
1822 static void cp210x_gpio_remove(struct usb_serial *serial)
1823 {
1824 	/* Nothing to do */
1825 }
1826 
1827 #endif
1828 
1829 static int cp210x_port_probe(struct usb_serial_port *port)
1830 {
1831 	struct usb_serial *serial = port->serial;
1832 	struct cp210x_port_private *port_priv;
1833 
1834 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1835 	if (!port_priv)
1836 		return -ENOMEM;
1837 
1838 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1839 	mutex_init(&port_priv->mutex);
1840 
1841 	usb_set_serial_port_data(port, port_priv);
1842 
1843 	return 0;
1844 }
1845 
1846 static void cp210x_port_remove(struct usb_serial_port *port)
1847 {
1848 	struct cp210x_port_private *port_priv;
1849 
1850 	port_priv = usb_get_serial_port_data(port);
1851 	kfree(port_priv);
1852 }
1853 
1854 static void cp210x_init_max_speed(struct usb_serial *serial)
1855 {
1856 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1857 	bool use_actual_rate = false;
1858 	speed_t min = 300;
1859 	speed_t max;
1860 
1861 	switch (priv->partnum) {
1862 	case CP210X_PARTNUM_CP2101:
1863 		max = 921600;
1864 		break;
1865 	case CP210X_PARTNUM_CP2102:
1866 	case CP210X_PARTNUM_CP2103:
1867 		max = 1000000;
1868 		break;
1869 	case CP210X_PARTNUM_CP2104:
1870 		use_actual_rate = true;
1871 		max = 2000000;
1872 		break;
1873 	case CP210X_PARTNUM_CP2108:
1874 		max = 2000000;
1875 		break;
1876 	case CP210X_PARTNUM_CP2105:
1877 		if (cp210x_interface_num(serial) == 0) {
1878 			use_actual_rate = true;
1879 			max = 2000000;	/* ECI */
1880 		} else {
1881 			min = 2400;
1882 			max = 921600;	/* SCI */
1883 		}
1884 		break;
1885 	case CP210X_PARTNUM_CP2102N_QFN28:
1886 	case CP210X_PARTNUM_CP2102N_QFN24:
1887 	case CP210X_PARTNUM_CP2102N_QFN20:
1888 		use_actual_rate = true;
1889 		max = 3000000;
1890 		break;
1891 	default:
1892 		max = 2000000;
1893 		break;
1894 	}
1895 
1896 	priv->min_speed = min;
1897 	priv->max_speed = max;
1898 	priv->use_actual_rate = use_actual_rate;
1899 }
1900 
1901 static int cp210x_attach(struct usb_serial *serial)
1902 {
1903 	int result;
1904 	struct cp210x_serial_private *priv;
1905 
1906 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1907 	if (!priv)
1908 		return -ENOMEM;
1909 
1910 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1911 					  CP210X_GET_PARTNUM, &priv->partnum,
1912 					  sizeof(priv->partnum));
1913 	if (result < 0) {
1914 		dev_warn(&serial->interface->dev,
1915 			 "querying part number failed\n");
1916 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1917 	}
1918 
1919 	usb_set_serial_data(serial, priv);
1920 
1921 	cp210x_init_max_speed(serial);
1922 
1923 	result = cp210x_gpio_init(serial);
1924 	if (result < 0) {
1925 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1926 				result);
1927 	}
1928 
1929 	return 0;
1930 }
1931 
1932 static void cp210x_disconnect(struct usb_serial *serial)
1933 {
1934 	cp210x_gpio_remove(serial);
1935 }
1936 
1937 static void cp210x_release(struct usb_serial *serial)
1938 {
1939 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1940 
1941 	cp210x_gpio_remove(serial);
1942 
1943 	kfree(priv);
1944 }
1945 
1946 module_usb_serial_driver(serial_drivers, id_table);
1947 
1948 MODULE_DESCRIPTION(DRIVER_DESC);
1949 MODULE_LICENSE("GPL v2");
1950