xref: /linux/drivers/usb/serial/cp210x.c (revision 43377df70480f82919032eb09832e9646a8a5efb)
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_change_speed(struct tty_struct *, struct usb_serial_port *,
35 							struct ktermios *);
36 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
37 							struct ktermios*);
38 static bool cp210x_tx_empty(struct usb_serial_port *port);
39 static int cp210x_tiocmget(struct tty_struct *);
40 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
41 static int cp210x_tiocmset_port(struct usb_serial_port *port,
42 		unsigned int, unsigned int);
43 static void cp210x_break_ctl(struct tty_struct *, int);
44 static int cp210x_attach(struct usb_serial *);
45 static void cp210x_disconnect(struct usb_serial *);
46 static void cp210x_release(struct usb_serial *);
47 static int cp210x_port_probe(struct usb_serial_port *);
48 static int cp210x_port_remove(struct usb_serial_port *);
49 static void cp210x_dtr_rts(struct usb_serial_port *port, int on);
50 static void cp210x_process_read_urb(struct urb *urb);
51 static void cp210x_enable_event_mode(struct usb_serial_port *port);
52 static void cp210x_disable_event_mode(struct usb_serial_port *port);
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(0x0988, 0x0578) }, /* Teraoka AD2000 */
65 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
66 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
67 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
68 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
69 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
70 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
71 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
72 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
73 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
74 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
75 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
76 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
77 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
78 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
79 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
80 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
81 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
82 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
83 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
84 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
85 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
86 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
87 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
88 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
89 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
90 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
91 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
92 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
93 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
94 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
95 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
96 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
97 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
98 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
99 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
100 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
101 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
104 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
105 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
106 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
107 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
108 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
109 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
110 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
111 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
112 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
113 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
114 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
115 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
116 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
117 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
118 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
119 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
120 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
121 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
122 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
123 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
124 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
125 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
126 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
127 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
128 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
129 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
130 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
131 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
132 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
133 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
134 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
135 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
136 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
137 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
138 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
139 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
140 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
141 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
142 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
143 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
144 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
145 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
146 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
147 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
148 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
149 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
150 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
151 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
152 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
153 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
154 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
155 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
156 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
157 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
158 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
159 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
160 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
161 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
162 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
163 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
164 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
165 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
166 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
167 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
168 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
169 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
170 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
171 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
172 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
173 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
174 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
175 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
176 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
177 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
178 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
179 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
180 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
181 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
182 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
183 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
184 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
185 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
186 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
187 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
188 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
189 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
190 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
191 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
192 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
193 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
194 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
195 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
196 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
197 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
198 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
199 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
200 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
201 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
202 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
203 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
204 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
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 
273 static struct usb_serial_driver cp210x_device = {
274 	.driver = {
275 		.owner =	THIS_MODULE,
276 		.name =		"cp210x",
277 	},
278 	.id_table		= id_table,
279 	.num_ports		= 1,
280 	.bulk_in_size		= 256,
281 	.bulk_out_size		= 256,
282 	.open			= cp210x_open,
283 	.close			= cp210x_close,
284 	.break_ctl		= cp210x_break_ctl,
285 	.set_termios		= cp210x_set_termios,
286 	.tx_empty		= cp210x_tx_empty,
287 	.throttle		= usb_serial_generic_throttle,
288 	.unthrottle		= usb_serial_generic_unthrottle,
289 	.tiocmget		= cp210x_tiocmget,
290 	.tiocmset		= cp210x_tiocmset,
291 	.get_icount		= usb_serial_generic_get_icount,
292 	.attach			= cp210x_attach,
293 	.disconnect		= cp210x_disconnect,
294 	.release		= cp210x_release,
295 	.port_probe		= cp210x_port_probe,
296 	.port_remove		= cp210x_port_remove,
297 	.dtr_rts		= cp210x_dtr_rts,
298 	.process_read_urb	= cp210x_process_read_urb,
299 };
300 
301 static struct usb_serial_driver * const serial_drivers[] = {
302 	&cp210x_device, NULL
303 };
304 
305 /* Config request types */
306 #define REQTYPE_HOST_TO_INTERFACE	0x41
307 #define REQTYPE_INTERFACE_TO_HOST	0xc1
308 #define REQTYPE_HOST_TO_DEVICE	0x40
309 #define REQTYPE_DEVICE_TO_HOST	0xc0
310 
311 /* Config request codes */
312 #define CP210X_IFC_ENABLE	0x00
313 #define CP210X_SET_BAUDDIV	0x01
314 #define CP210X_GET_BAUDDIV	0x02
315 #define CP210X_SET_LINE_CTL	0x03
316 #define CP210X_GET_LINE_CTL	0x04
317 #define CP210X_SET_BREAK	0x05
318 #define CP210X_IMM_CHAR		0x06
319 #define CP210X_SET_MHS		0x07
320 #define CP210X_GET_MDMSTS	0x08
321 #define CP210X_SET_XON		0x09
322 #define CP210X_SET_XOFF		0x0A
323 #define CP210X_SET_EVENTMASK	0x0B
324 #define CP210X_GET_EVENTMASK	0x0C
325 #define CP210X_SET_CHAR		0x0D
326 #define CP210X_GET_CHARS	0x0E
327 #define CP210X_GET_PROPS	0x0F
328 #define CP210X_GET_COMM_STATUS	0x10
329 #define CP210X_RESET		0x11
330 #define CP210X_PURGE		0x12
331 #define CP210X_SET_FLOW		0x13
332 #define CP210X_GET_FLOW		0x14
333 #define CP210X_EMBED_EVENTS	0x15
334 #define CP210X_GET_EVENTSTATE	0x16
335 #define CP210X_SET_CHARS	0x19
336 #define CP210X_GET_BAUDRATE	0x1D
337 #define CP210X_SET_BAUDRATE	0x1E
338 #define CP210X_VENDOR_SPECIFIC	0xFF
339 
340 /* CP210X_IFC_ENABLE */
341 #define UART_ENABLE		0x0001
342 #define UART_DISABLE		0x0000
343 
344 /* CP210X_(SET|GET)_BAUDDIV */
345 #define BAUD_RATE_GEN_FREQ	0x384000
346 
347 /* CP210X_(SET|GET)_LINE_CTL */
348 #define BITS_DATA_MASK		0X0f00
349 #define BITS_DATA_5		0X0500
350 #define BITS_DATA_6		0X0600
351 #define BITS_DATA_7		0X0700
352 #define BITS_DATA_8		0X0800
353 #define BITS_DATA_9		0X0900
354 
355 #define BITS_PARITY_MASK	0x00f0
356 #define BITS_PARITY_NONE	0x0000
357 #define BITS_PARITY_ODD		0x0010
358 #define BITS_PARITY_EVEN	0x0020
359 #define BITS_PARITY_MARK	0x0030
360 #define BITS_PARITY_SPACE	0x0040
361 
362 #define BITS_STOP_MASK		0x000f
363 #define BITS_STOP_1		0x0000
364 #define BITS_STOP_1_5		0x0001
365 #define BITS_STOP_2		0x0002
366 
367 /* CP210X_SET_BREAK */
368 #define BREAK_ON		0x0001
369 #define BREAK_OFF		0x0000
370 
371 /* CP210X_(SET_MHS|GET_MDMSTS) */
372 #define CONTROL_DTR		0x0001
373 #define CONTROL_RTS		0x0002
374 #define CONTROL_CTS		0x0010
375 #define CONTROL_DSR		0x0020
376 #define CONTROL_RING		0x0040
377 #define CONTROL_DCD		0x0080
378 #define CONTROL_WRITE_DTR	0x0100
379 #define CONTROL_WRITE_RTS	0x0200
380 
381 /* CP210X_VENDOR_SPECIFIC values */
382 #define CP210X_READ_2NCONFIG	0x000E
383 #define CP210X_READ_LATCH	0x00C2
384 #define CP210X_GET_PARTNUM	0x370B
385 #define CP210X_GET_PORTCONFIG	0x370C
386 #define CP210X_GET_DEVICEMODE	0x3711
387 #define CP210X_WRITE_LATCH	0x37E1
388 
389 /* Part number definitions */
390 #define CP210X_PARTNUM_CP2101	0x01
391 #define CP210X_PARTNUM_CP2102	0x02
392 #define CP210X_PARTNUM_CP2103	0x03
393 #define CP210X_PARTNUM_CP2104	0x04
394 #define CP210X_PARTNUM_CP2105	0x05
395 #define CP210X_PARTNUM_CP2108	0x08
396 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
397 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
398 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
399 #define CP210X_PARTNUM_UNKNOWN	0xFF
400 
401 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
402 struct cp210x_comm_status {
403 	__le32   ulErrors;
404 	__le32   ulHoldReasons;
405 	__le32   ulAmountInInQueue;
406 	__le32   ulAmountInOutQueue;
407 	u8       bEofReceived;
408 	u8       bWaitForImmediate;
409 	u8       bReserved;
410 } __packed;
411 
412 /*
413  * CP210X_PURGE - 16 bits passed in wValue of USB request.
414  * SiLabs app note AN571 gives a strange description of the 4 bits:
415  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
416  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
417  */
418 #define PURGE_ALL		0x000f
419 
420 /* CP210X_EMBED_EVENTS */
421 #define CP210X_ESCCHAR		0xec
422 
423 #define CP210X_LSR_OVERRUN	BIT(1)
424 #define CP210X_LSR_PARITY	BIT(2)
425 #define CP210X_LSR_FRAME	BIT(3)
426 #define CP210X_LSR_BREAK	BIT(4)
427 
428 
429 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
430 struct cp210x_flow_ctl {
431 	__le32	ulControlHandshake;
432 	__le32	ulFlowReplace;
433 	__le32	ulXonLimit;
434 	__le32	ulXoffLimit;
435 };
436 
437 /* cp210x_flow_ctl::ulControlHandshake */
438 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
439 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
440 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
441 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
442 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
443 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
444 
445 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
446 #define CP210X_SERIAL_DTR_INACTIVE	0
447 #define CP210X_SERIAL_DTR_ACTIVE	1
448 #define CP210X_SERIAL_DTR_FLOW_CTL	2
449 
450 /* cp210x_flow_ctl::ulFlowReplace */
451 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
452 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
453 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
454 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
455 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
456 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
457 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
458 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
459 
460 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
461 #define CP210X_SERIAL_RTS_INACTIVE	0
462 #define CP210X_SERIAL_RTS_ACTIVE	1
463 #define CP210X_SERIAL_RTS_FLOW_CTL	2
464 
465 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
466 struct cp210x_pin_mode {
467 	u8	eci;
468 	u8	sci;
469 };
470 
471 #define CP210X_PIN_MODE_MODEM		0
472 #define CP210X_PIN_MODE_GPIO		BIT(0)
473 
474 /*
475  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
476  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
477  */
478 struct cp210x_dual_port_config {
479 	__le16	gpio_mode;
480 	u8	__pad0[2];
481 	__le16	reset_state;
482 	u8	__pad1[4];
483 	__le16	suspend_state;
484 	u8	sci_cfg;
485 	u8	eci_cfg;
486 	u8	device_cfg;
487 } __packed;
488 
489 /*
490  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
491  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
492  */
493 struct cp210x_single_port_config {
494 	__le16	gpio_mode;
495 	u8	__pad0[2];
496 	__le16	reset_state;
497 	u8	__pad1[4];
498 	__le16	suspend_state;
499 	u8	device_cfg;
500 } __packed;
501 
502 /* GPIO modes */
503 #define CP210X_SCI_GPIO_MODE_OFFSET	9
504 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
505 
506 #define CP210X_ECI_GPIO_MODE_OFFSET	2
507 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
508 
509 #define CP210X_GPIO_MODE_OFFSET		8
510 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
511 
512 /* CP2105 port configuration values */
513 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
514 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
515 #define CP2105_GPIO1_RS485_MODE		BIT(2)
516 
517 /* CP2104 port configuration values */
518 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
519 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
520 #define CP2104_GPIO2_RS485_MODE		BIT(2)
521 
522 /* CP2102N configuration array indices */
523 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
524 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
525 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
526 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
527 
528 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
529 struct cp210x_gpio_write {
530 	u8	mask;
531 	u8	state;
532 };
533 
534 /*
535  * Helper to get interface number when we only have struct usb_serial.
536  */
537 static u8 cp210x_interface_num(struct usb_serial *serial)
538 {
539 	struct usb_host_interface *cur_altsetting;
540 
541 	cur_altsetting = serial->interface->cur_altsetting;
542 
543 	return cur_altsetting->desc.bInterfaceNumber;
544 }
545 
546 /*
547  * Reads a variable-sized block of CP210X_ registers, identified by req.
548  * Returns data into buf in native USB byte order.
549  */
550 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
551 		void *buf, int bufsize)
552 {
553 	struct usb_serial *serial = port->serial;
554 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
555 	void *dmabuf;
556 	int result;
557 
558 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
559 	if (!dmabuf)
560 		return -ENOMEM;
561 
562 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
563 			req, REQTYPE_INTERFACE_TO_HOST, 0,
564 			port_priv->bInterfaceNumber, dmabuf, bufsize,
565 			USB_CTRL_SET_TIMEOUT);
566 	if (result == bufsize) {
567 		memcpy(buf, dmabuf, bufsize);
568 		result = 0;
569 	} else {
570 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
571 				req, bufsize, result);
572 		if (result >= 0)
573 			result = -EIO;
574 	}
575 
576 	kfree(dmabuf);
577 
578 	return result;
579 }
580 
581 /*
582  * Reads any 8-bit CP210X_ register identified by req.
583  */
584 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
585 {
586 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
587 }
588 
589 /*
590  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
591  * Returns data into buf in native USB byte order.
592  */
593 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
594 				    void *buf, int bufsize)
595 {
596 	void *dmabuf;
597 	int result;
598 
599 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
600 	if (!dmabuf)
601 		return -ENOMEM;
602 
603 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
604 				 CP210X_VENDOR_SPECIFIC, type, val,
605 				 cp210x_interface_num(serial), dmabuf, bufsize,
606 				 USB_CTRL_GET_TIMEOUT);
607 	if (result == bufsize) {
608 		memcpy(buf, dmabuf, bufsize);
609 		result = 0;
610 	} else {
611 		dev_err(&serial->interface->dev,
612 			"failed to get vendor val 0x%04x size %d: %d\n", val,
613 			bufsize, result);
614 		if (result >= 0)
615 			result = -EIO;
616 	}
617 
618 	kfree(dmabuf);
619 
620 	return result;
621 }
622 
623 /*
624  * Writes any 16-bit CP210X_ register (req) whose value is passed
625  * entirely in the wValue field of the USB request.
626  */
627 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
628 {
629 	struct usb_serial *serial = port->serial;
630 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
631 	int result;
632 
633 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
634 			req, REQTYPE_HOST_TO_INTERFACE, val,
635 			port_priv->bInterfaceNumber, NULL, 0,
636 			USB_CTRL_SET_TIMEOUT);
637 	if (result < 0) {
638 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
639 				req, result);
640 	}
641 
642 	return result;
643 }
644 
645 /*
646  * Writes a variable-sized block of CP210X_ registers, identified by req.
647  * Data in buf must be in native USB byte order.
648  */
649 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
650 		void *buf, int bufsize)
651 {
652 	struct usb_serial *serial = port->serial;
653 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
654 	void *dmabuf;
655 	int result;
656 
657 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
658 	if (!dmabuf)
659 		return -ENOMEM;
660 
661 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
662 			req, REQTYPE_HOST_TO_INTERFACE, 0,
663 			port_priv->bInterfaceNumber, dmabuf, bufsize,
664 			USB_CTRL_SET_TIMEOUT);
665 
666 	kfree(dmabuf);
667 
668 	if (result == bufsize) {
669 		result = 0;
670 	} else {
671 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
672 				req, bufsize, result);
673 		if (result >= 0)
674 			result = -EIO;
675 	}
676 
677 	return result;
678 }
679 
680 /*
681  * Writes any 32-bit CP210X_ register identified by req.
682  */
683 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
684 {
685 	__le32 le32_val;
686 
687 	le32_val = cpu_to_le32(val);
688 
689 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
690 }
691 
692 #ifdef CONFIG_GPIOLIB
693 /*
694  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
695  * Data in buf must be in native USB byte order.
696  */
697 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
698 				     u16 val, void *buf, int bufsize)
699 {
700 	void *dmabuf;
701 	int result;
702 
703 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
704 	if (!dmabuf)
705 		return -ENOMEM;
706 
707 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
708 				 CP210X_VENDOR_SPECIFIC, type, val,
709 				 cp210x_interface_num(serial), dmabuf, bufsize,
710 				 USB_CTRL_SET_TIMEOUT);
711 
712 	kfree(dmabuf);
713 
714 	if (result == bufsize) {
715 		result = 0;
716 	} else {
717 		dev_err(&serial->interface->dev,
718 			"failed to set vendor val 0x%04x size %d: %d\n", val,
719 			bufsize, result);
720 		if (result >= 0)
721 			result = -EIO;
722 	}
723 
724 	return result;
725 }
726 #endif
727 
728 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
729 {
730 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
731 	int result;
732 
733 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
734 	if (result) {
735 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
736 		return result;
737 	}
738 
739 	if (tty)
740 		cp210x_set_termios(tty, port, NULL);
741 
742 	result = usb_serial_generic_open(tty, port);
743 	if (result)
744 		goto err_disable;
745 
746 	return 0;
747 
748 err_disable:
749 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
750 	port_priv->event_mode = false;
751 
752 	return result;
753 }
754 
755 static void cp210x_close(struct usb_serial_port *port)
756 {
757 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
758 
759 	usb_serial_generic_close(port);
760 
761 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
762 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
763 
764 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
765 
766 	/* Disabling the interface disables event-insertion mode. */
767 	port_priv->event_mode = false;
768 }
769 
770 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
771 {
772 	if (lsr & CP210X_LSR_BREAK) {
773 		port->icount.brk++;
774 		*flag = TTY_BREAK;
775 	} else if (lsr & CP210X_LSR_PARITY) {
776 		port->icount.parity++;
777 		*flag = TTY_PARITY;
778 	} else if (lsr & CP210X_LSR_FRAME) {
779 		port->icount.frame++;
780 		*flag = TTY_FRAME;
781 	}
782 
783 	if (lsr & CP210X_LSR_OVERRUN) {
784 		port->icount.overrun++;
785 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
786 	}
787 }
788 
789 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
790 {
791 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
792 
793 	switch (port_priv->event_state) {
794 	case ES_DATA:
795 		if (*ch == CP210X_ESCCHAR) {
796 			port_priv->event_state = ES_ESCAPE;
797 			break;
798 		}
799 		return false;
800 	case ES_ESCAPE:
801 		switch (*ch) {
802 		case 0:
803 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
804 			*ch = CP210X_ESCCHAR;
805 			port_priv->event_state = ES_DATA;
806 			return false;
807 		case 1:
808 			port_priv->event_state = ES_LSR_DATA_0;
809 			break;
810 		case 2:
811 			port_priv->event_state = ES_LSR;
812 			break;
813 		case 3:
814 			port_priv->event_state = ES_MSR;
815 			break;
816 		default:
817 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
818 			port_priv->event_state = ES_DATA;
819 			break;
820 		}
821 		break;
822 	case ES_LSR_DATA_0:
823 		port_priv->lsr = *ch;
824 		port_priv->event_state = ES_LSR_DATA_1;
825 		break;
826 	case ES_LSR_DATA_1:
827 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
828 				__func__, port_priv->lsr, *ch);
829 		cp210x_process_lsr(port, port_priv->lsr, flag);
830 		port_priv->event_state = ES_DATA;
831 		return false;
832 	case ES_LSR:
833 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
834 		port_priv->lsr = *ch;
835 		cp210x_process_lsr(port, port_priv->lsr, flag);
836 		port_priv->event_state = ES_DATA;
837 		break;
838 	case ES_MSR:
839 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
840 		/* unimplemented */
841 		port_priv->event_state = ES_DATA;
842 		break;
843 	}
844 
845 	return true;
846 }
847 
848 static void cp210x_process_read_urb(struct urb *urb)
849 {
850 	struct usb_serial_port *port = urb->context;
851 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
852 	unsigned char *ch = urb->transfer_buffer;
853 	char flag;
854 	int i;
855 
856 	if (!urb->actual_length)
857 		return;
858 
859 	if (port_priv->event_mode) {
860 		for (i = 0; i < urb->actual_length; i++, ch++) {
861 			flag = TTY_NORMAL;
862 
863 			if (cp210x_process_char(port, ch, &flag))
864 				continue;
865 
866 			tty_insert_flip_char(&port->port, *ch, flag);
867 		}
868 	} else {
869 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
870 	}
871 	tty_flip_buffer_push(&port->port);
872 }
873 
874 /*
875  * Read how many bytes are waiting in the TX queue.
876  */
877 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
878 		u32 *count)
879 {
880 	struct usb_serial *serial = port->serial;
881 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
882 	struct cp210x_comm_status *sts;
883 	int result;
884 
885 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
886 	if (!sts)
887 		return -ENOMEM;
888 
889 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
890 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
891 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
892 			USB_CTRL_GET_TIMEOUT);
893 	if (result == sizeof(*sts)) {
894 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
895 		result = 0;
896 	} else {
897 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
898 		if (result >= 0)
899 			result = -EIO;
900 	}
901 
902 	kfree(sts);
903 
904 	return result;
905 }
906 
907 static bool cp210x_tx_empty(struct usb_serial_port *port)
908 {
909 	int err;
910 	u32 count;
911 
912 	err = cp210x_get_tx_queue_byte_count(port, &count);
913 	if (err)
914 		return true;
915 
916 	return !count;
917 }
918 
919 struct cp210x_rate {
920 	speed_t rate;
921 	speed_t high;
922 };
923 
924 static const struct cp210x_rate cp210x_an205_table1[] = {
925 	{ 300, 300 },
926 	{ 600, 600 },
927 	{ 1200, 1200 },
928 	{ 1800, 1800 },
929 	{ 2400, 2400 },
930 	{ 4000, 4000 },
931 	{ 4800, 4803 },
932 	{ 7200, 7207 },
933 	{ 9600, 9612 },
934 	{ 14400, 14428 },
935 	{ 16000, 16062 },
936 	{ 19200, 19250 },
937 	{ 28800, 28912 },
938 	{ 38400, 38601 },
939 	{ 51200, 51558 },
940 	{ 56000, 56280 },
941 	{ 57600, 58053 },
942 	{ 64000, 64111 },
943 	{ 76800, 77608 },
944 	{ 115200, 117028 },
945 	{ 128000, 129347 },
946 	{ 153600, 156868 },
947 	{ 230400, 237832 },
948 	{ 250000, 254234 },
949 	{ 256000, 273066 },
950 	{ 460800, 491520 },
951 	{ 500000, 567138 },
952 	{ 576000, 670254 },
953 	{ 921600, UINT_MAX }
954 };
955 
956 /*
957  * Quantises the baud rate as per AN205 Table 1
958  */
959 static speed_t cp210x_get_an205_rate(speed_t baud)
960 {
961 	int i;
962 
963 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
964 		if (baud <= cp210x_an205_table1[i].high)
965 			break;
966 	}
967 
968 	return cp210x_an205_table1[i].rate;
969 }
970 
971 static speed_t cp210x_get_actual_rate(speed_t baud)
972 {
973 	unsigned int prescale = 1;
974 	unsigned int div;
975 
976 	if (baud <= 365)
977 		prescale = 4;
978 
979 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
980 	baud = 48000000 / (2 * prescale * div);
981 
982 	return baud;
983 }
984 
985 /*
986  * CP2101 supports the following baud rates:
987  *
988  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
989  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
990  *
991  * CP2102 and CP2103 support the following additional rates:
992  *
993  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
994  *	576000
995  *
996  * The device will map a requested rate to a supported one, but the result
997  * of requests for rates greater than 1053257 is undefined (see AN205).
998  *
999  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1000  * respectively, with an error less than 1%. The actual rates are determined
1001  * by
1002  *
1003  *	div = round(freq / (2 x prescale x request))
1004  *	actual = freq / (2 x prescale x div)
1005  *
1006  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1007  * or 1 otherwise.
1008  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1009  * otherwise.
1010  */
1011 static void cp210x_change_speed(struct tty_struct *tty,
1012 		struct usb_serial_port *port, struct ktermios *old_termios)
1013 {
1014 	struct usb_serial *serial = port->serial;
1015 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1016 	u32 baud;
1017 
1018 	/*
1019 	 * This maps the requested rate to the actual rate, a valid rate on
1020 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1021 	 *
1022 	 * NOTE: B0 is not implemented.
1023 	 */
1024 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1025 
1026 	if (priv->use_actual_rate)
1027 		baud = cp210x_get_actual_rate(baud);
1028 	else if (baud < 1000000)
1029 		baud = cp210x_get_an205_rate(baud);
1030 
1031 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1032 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1033 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1034 		if (old_termios)
1035 			baud = old_termios->c_ospeed;
1036 		else
1037 			baud = 9600;
1038 	}
1039 
1040 	tty_encode_baud_rate(tty, baud, baud);
1041 }
1042 
1043 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1044 {
1045 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1046 	int ret;
1047 
1048 	if (port_priv->event_mode)
1049 		return;
1050 
1051 	port_priv->event_state = ES_DATA;
1052 	port_priv->event_mode = true;
1053 
1054 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1055 	if (ret) {
1056 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1057 		port_priv->event_mode = false;
1058 	}
1059 }
1060 
1061 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1062 {
1063 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1064 	int ret;
1065 
1066 	if (!port_priv->event_mode)
1067 		return;
1068 
1069 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1070 	if (ret) {
1071 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1072 		return;
1073 	}
1074 
1075 	port_priv->event_mode = false;
1076 }
1077 
1078 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1079 {
1080 	bool iflag_change;
1081 
1082 	iflag_change = ((a->c_iflag ^ b->c_iflag) & INPCK);
1083 
1084 	return tty_termios_hw_change(a, b) || iflag_change;
1085 }
1086 
1087 static void cp210x_set_flow_control(struct tty_struct *tty,
1088 		struct usb_serial_port *port, struct ktermios *old_termios)
1089 {
1090 	struct cp210x_flow_ctl flow_ctl;
1091 	u32 flow_repl;
1092 	u32 ctl_hs;
1093 	int ret;
1094 
1095 	if (old_termios && C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS))
1096 		return;
1097 
1098 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1099 			sizeof(flow_ctl));
1100 	if (ret)
1101 		return;
1102 
1103 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1104 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1105 
1106 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1107 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1108 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1109 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1110 	ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1111 
1112 	if (C_CRTSCTS(tty)) {
1113 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1114 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1115 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
1116 	} else {
1117 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1118 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1119 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_ACTIVE);
1120 	}
1121 
1122 	dev_dbg(&port->dev, "%s - ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1123 			__func__, ctl_hs, flow_repl);
1124 
1125 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1126 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1127 
1128 	cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1129 			sizeof(flow_ctl));
1130 }
1131 
1132 static void cp210x_set_termios(struct tty_struct *tty,
1133 		struct usb_serial_port *port, struct ktermios *old_termios)
1134 {
1135 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1136 	u16 bits;
1137 	int ret;
1138 
1139 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1140 		return;
1141 
1142 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1143 		cp210x_change_speed(tty, port, old_termios);
1144 
1145 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1146 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1147 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1148 		tty->termios.c_cflag |= CS8;
1149 	}
1150 
1151 	bits = 0;
1152 
1153 	switch (C_CSIZE(tty)) {
1154 	case CS5:
1155 		bits |= BITS_DATA_5;
1156 		break;
1157 	case CS6:
1158 		bits |= BITS_DATA_6;
1159 		break;
1160 	case CS7:
1161 		bits |= BITS_DATA_7;
1162 		break;
1163 	case CS8:
1164 	default:
1165 		bits |= BITS_DATA_8;
1166 		break;
1167 	}
1168 
1169 	if (C_PARENB(tty)) {
1170 		if (C_CMSPAR(tty)) {
1171 			if (C_PARODD(tty))
1172 				bits |= BITS_PARITY_MARK;
1173 			else
1174 				bits |= BITS_PARITY_SPACE;
1175 		} else {
1176 			if (C_PARODD(tty))
1177 				bits |= BITS_PARITY_ODD;
1178 			else
1179 				bits |= BITS_PARITY_EVEN;
1180 		}
1181 	}
1182 
1183 	if (C_CSTOPB(tty))
1184 		bits |= BITS_STOP_2;
1185 	else
1186 		bits |= BITS_STOP_1;
1187 
1188 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1189 	if (ret)
1190 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1191 
1192 	cp210x_set_flow_control(tty, port, old_termios);
1193 
1194 	/*
1195 	 * Enable event-insertion mode only if input parity checking is
1196 	 * enabled for now.
1197 	 */
1198 	if (I_INPCK(tty))
1199 		cp210x_enable_event_mode(port);
1200 	else
1201 		cp210x_disable_event_mode(port);
1202 }
1203 
1204 static int cp210x_tiocmset(struct tty_struct *tty,
1205 		unsigned int set, unsigned int clear)
1206 {
1207 	struct usb_serial_port *port = tty->driver_data;
1208 	return cp210x_tiocmset_port(port, set, clear);
1209 }
1210 
1211 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1212 		unsigned int set, unsigned int clear)
1213 {
1214 	u16 control = 0;
1215 
1216 	if (set & TIOCM_RTS) {
1217 		control |= CONTROL_RTS;
1218 		control |= CONTROL_WRITE_RTS;
1219 	}
1220 	if (set & TIOCM_DTR) {
1221 		control |= CONTROL_DTR;
1222 		control |= CONTROL_WRITE_DTR;
1223 	}
1224 	if (clear & TIOCM_RTS) {
1225 		control &= ~CONTROL_RTS;
1226 		control |= CONTROL_WRITE_RTS;
1227 	}
1228 	if (clear & TIOCM_DTR) {
1229 		control &= ~CONTROL_DTR;
1230 		control |= CONTROL_WRITE_DTR;
1231 	}
1232 
1233 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1234 
1235 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1236 }
1237 
1238 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1239 {
1240 	if (on)
1241 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1242 	else
1243 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1244 }
1245 
1246 static int cp210x_tiocmget(struct tty_struct *tty)
1247 {
1248 	struct usb_serial_port *port = tty->driver_data;
1249 	u8 control;
1250 	int result;
1251 
1252 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1253 	if (result)
1254 		return result;
1255 
1256 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1257 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1258 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1259 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1260 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1261 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1262 
1263 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1264 
1265 	return result;
1266 }
1267 
1268 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1269 {
1270 	struct usb_serial_port *port = tty->driver_data;
1271 	u16 state;
1272 
1273 	if (break_state == 0)
1274 		state = BREAK_OFF;
1275 	else
1276 		state = BREAK_ON;
1277 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1278 		state == BREAK_OFF ? "off" : "on");
1279 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1280 }
1281 
1282 #ifdef CONFIG_GPIOLIB
1283 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1284 {
1285 	struct usb_serial *serial = gpiochip_get_data(gc);
1286 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1287 
1288 	if (priv->gpio_altfunc & BIT(offset))
1289 		return -ENODEV;
1290 
1291 	return 0;
1292 }
1293 
1294 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1295 {
1296 	struct usb_serial *serial = gpiochip_get_data(gc);
1297 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1298 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1299 	int result;
1300 	u8 buf;
1301 
1302 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1303 		req_type = REQTYPE_INTERFACE_TO_HOST;
1304 
1305 	result = usb_autopm_get_interface(serial->interface);
1306 	if (result)
1307 		return result;
1308 
1309 	result = cp210x_read_vendor_block(serial, req_type,
1310 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1311 	usb_autopm_put_interface(serial->interface);
1312 	if (result < 0)
1313 		return result;
1314 
1315 	return !!(buf & BIT(gpio));
1316 }
1317 
1318 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1319 {
1320 	struct usb_serial *serial = gpiochip_get_data(gc);
1321 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1322 	struct cp210x_gpio_write buf;
1323 	int result;
1324 
1325 	if (value == 1)
1326 		buf.state = BIT(gpio);
1327 	else
1328 		buf.state = 0;
1329 
1330 	buf.mask = BIT(gpio);
1331 
1332 	result = usb_autopm_get_interface(serial->interface);
1333 	if (result)
1334 		goto out;
1335 
1336 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1337 		result = cp210x_write_vendor_block(serial,
1338 						   REQTYPE_HOST_TO_INTERFACE,
1339 						   CP210X_WRITE_LATCH, &buf,
1340 						   sizeof(buf));
1341 	} else {
1342 		u16 wIndex = buf.state << 8 | buf.mask;
1343 
1344 		result = usb_control_msg(serial->dev,
1345 					 usb_sndctrlpipe(serial->dev, 0),
1346 					 CP210X_VENDOR_SPECIFIC,
1347 					 REQTYPE_HOST_TO_DEVICE,
1348 					 CP210X_WRITE_LATCH,
1349 					 wIndex,
1350 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1351 	}
1352 
1353 	usb_autopm_put_interface(serial->interface);
1354 out:
1355 	if (result < 0) {
1356 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1357 				result);
1358 	}
1359 }
1360 
1361 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1362 {
1363 	struct usb_serial *serial = gpiochip_get_data(gc);
1364 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1365 
1366 	return priv->gpio_input & BIT(gpio);
1367 }
1368 
1369 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1370 {
1371 	struct usb_serial *serial = gpiochip_get_data(gc);
1372 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1373 
1374 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1375 		/* hardware does not support an input mode */
1376 		return -ENOTSUPP;
1377 	}
1378 
1379 	/* push-pull pins cannot be changed to be inputs */
1380 	if (priv->gpio_pushpull & BIT(gpio))
1381 		return -EINVAL;
1382 
1383 	/* make sure to release pin if it is being driven low */
1384 	cp210x_gpio_set(gc, gpio, 1);
1385 
1386 	priv->gpio_input |= BIT(gpio);
1387 
1388 	return 0;
1389 }
1390 
1391 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1392 					int value)
1393 {
1394 	struct usb_serial *serial = gpiochip_get_data(gc);
1395 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1396 
1397 	priv->gpio_input &= ~BIT(gpio);
1398 	cp210x_gpio_set(gc, gpio, value);
1399 
1400 	return 0;
1401 }
1402 
1403 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1404 				  unsigned long config)
1405 {
1406 	struct usb_serial *serial = gpiochip_get_data(gc);
1407 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1408 	enum pin_config_param param = pinconf_to_config_param(config);
1409 
1410 	/* Succeed only if in correct mode (this can't be set at runtime) */
1411 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1412 	    (priv->gpio_pushpull & BIT(gpio)))
1413 		return 0;
1414 
1415 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1416 	    !(priv->gpio_pushpull & BIT(gpio)))
1417 		return 0;
1418 
1419 	return -ENOTSUPP;
1420 }
1421 
1422 /*
1423  * This function is for configuring GPIO using shared pins, where other signals
1424  * are made unavailable by configuring the use of GPIO. This is believed to be
1425  * only applicable to the cp2105 at this point, the other devices supported by
1426  * this driver that provide GPIO do so in a way that does not impact other
1427  * signals and are thus expected to have very different initialisation.
1428  */
1429 static int cp2105_gpioconf_init(struct usb_serial *serial)
1430 {
1431 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1432 	struct cp210x_pin_mode mode;
1433 	struct cp210x_dual_port_config config;
1434 	u8 intf_num = cp210x_interface_num(serial);
1435 	u8 iface_config;
1436 	int result;
1437 
1438 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1439 					  CP210X_GET_DEVICEMODE, &mode,
1440 					  sizeof(mode));
1441 	if (result < 0)
1442 		return result;
1443 
1444 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1445 					  CP210X_GET_PORTCONFIG, &config,
1446 					  sizeof(config));
1447 	if (result < 0)
1448 		return result;
1449 
1450 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1451 	if (intf_num == 0) {
1452 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1453 			/* mark all GPIOs of this interface as reserved */
1454 			priv->gpio_altfunc = 0xff;
1455 			return 0;
1456 		}
1457 
1458 		iface_config = config.eci_cfg;
1459 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1460 						CP210X_ECI_GPIO_MODE_MASK) >>
1461 						CP210X_ECI_GPIO_MODE_OFFSET);
1462 		priv->gc.ngpio = 2;
1463 	} else if (intf_num == 1) {
1464 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1465 			/* mark all GPIOs of this interface as reserved */
1466 			priv->gpio_altfunc = 0xff;
1467 			return 0;
1468 		}
1469 
1470 		iface_config = config.sci_cfg;
1471 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1472 						CP210X_SCI_GPIO_MODE_MASK) >>
1473 						CP210X_SCI_GPIO_MODE_OFFSET);
1474 		priv->gc.ngpio = 3;
1475 	} else {
1476 		return -ENODEV;
1477 	}
1478 
1479 	/* mark all pins which are not in GPIO mode */
1480 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1481 		priv->gpio_altfunc |= BIT(0);
1482 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1483 			CP2105_GPIO1_RS485_MODE))
1484 		priv->gpio_altfunc |= BIT(1);
1485 
1486 	/* driver implementation for CP2105 only supports outputs */
1487 	priv->gpio_input = 0;
1488 
1489 	return 0;
1490 }
1491 
1492 static int cp2104_gpioconf_init(struct usb_serial *serial)
1493 {
1494 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1495 	struct cp210x_single_port_config config;
1496 	u8 iface_config;
1497 	u8 gpio_latch;
1498 	int result;
1499 	u8 i;
1500 
1501 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1502 					  CP210X_GET_PORTCONFIG, &config,
1503 					  sizeof(config));
1504 	if (result < 0)
1505 		return result;
1506 
1507 	priv->gc.ngpio = 4;
1508 
1509 	iface_config = config.device_cfg;
1510 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1511 					CP210X_GPIO_MODE_MASK) >>
1512 					CP210X_GPIO_MODE_OFFSET);
1513 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1514 					CP210X_GPIO_MODE_MASK) >>
1515 					CP210X_GPIO_MODE_OFFSET);
1516 
1517 	/* mark all pins which are not in GPIO mode */
1518 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1519 		priv->gpio_altfunc |= BIT(0);
1520 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1521 		priv->gpio_altfunc |= BIT(1);
1522 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1523 		priv->gpio_altfunc |= BIT(2);
1524 
1525 	/*
1526 	 * Like CP2102N, CP2104 has also no strict input and output pin
1527 	 * modes.
1528 	 * Do the same input mode emulation as CP2102N.
1529 	 */
1530 	for (i = 0; i < priv->gc.ngpio; ++i) {
1531 		/*
1532 		 * Set direction to "input" iff pin is open-drain and reset
1533 		 * value is 1.
1534 		 */
1535 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1536 			priv->gpio_input |= BIT(i);
1537 	}
1538 
1539 	return 0;
1540 }
1541 
1542 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1543 {
1544 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1545 	const u16 config_size = 0x02a6;
1546 	u8 gpio_rst_latch;
1547 	u8 config_version;
1548 	u8 gpio_pushpull;
1549 	u8 *config_buf;
1550 	u8 gpio_latch;
1551 	u8 gpio_ctrl;
1552 	int result;
1553 	u8 i;
1554 
1555 	/*
1556 	 * Retrieve device configuration from the device.
1557 	 * The array received contains all customization settings done at the
1558 	 * factory/manufacturer. Format of the array is documented at the
1559 	 * time of writing at:
1560 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1561 	 */
1562 	config_buf = kmalloc(config_size, GFP_KERNEL);
1563 	if (!config_buf)
1564 		return -ENOMEM;
1565 
1566 	result = cp210x_read_vendor_block(serial,
1567 					  REQTYPE_DEVICE_TO_HOST,
1568 					  CP210X_READ_2NCONFIG,
1569 					  config_buf,
1570 					  config_size);
1571 	if (result < 0) {
1572 		kfree(config_buf);
1573 		return result;
1574 	}
1575 
1576 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1577 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1578 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1579 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1580 
1581 	kfree(config_buf);
1582 
1583 	/* Make sure this is a config format we understand. */
1584 	if (config_version != 0x01)
1585 		return -ENOTSUPP;
1586 
1587 	priv->gc.ngpio = 4;
1588 
1589 	/*
1590 	 * Get default pin states after reset. Needed so we can determine
1591 	 * the direction of an open-drain pin.
1592 	 */
1593 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1594 
1595 	/* 0 indicates open-drain mode, 1 is push-pull */
1596 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1597 
1598 	/* 0 indicates GPIO mode, 1 is alternate function */
1599 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1600 
1601 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1602 		/*
1603 		 * For the QFN28 package, GPIO4-6 are controlled by
1604 		 * the low three bits of the mode/latch fields.
1605 		 * Contrary to the document linked above, the bits for
1606 		 * the SUSPEND pins are elsewhere.  No alternate
1607 		 * function is available for these pins.
1608 		 */
1609 		priv->gc.ngpio = 7;
1610 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1611 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1612 	}
1613 
1614 	/*
1615 	 * The CP2102N does not strictly has input and output pin modes,
1616 	 * it only knows open-drain and push-pull modes which is set at
1617 	 * factory. An open-drain pin can function both as an
1618 	 * input or an output. We emulate input mode for open-drain pins
1619 	 * by making sure they are not driven low, and we do not allow
1620 	 * push-pull pins to be set as an input.
1621 	 */
1622 	for (i = 0; i < priv->gc.ngpio; ++i) {
1623 		/*
1624 		 * Set direction to "input" iff pin is open-drain and reset
1625 		 * value is 1.
1626 		 */
1627 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1628 			priv->gpio_input |= BIT(i);
1629 	}
1630 
1631 	return 0;
1632 }
1633 
1634 static int cp210x_gpio_init(struct usb_serial *serial)
1635 {
1636 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1637 	int result;
1638 
1639 	switch (priv->partnum) {
1640 	case CP210X_PARTNUM_CP2104:
1641 		result = cp2104_gpioconf_init(serial);
1642 		break;
1643 	case CP210X_PARTNUM_CP2105:
1644 		result = cp2105_gpioconf_init(serial);
1645 		break;
1646 	case CP210X_PARTNUM_CP2102N_QFN28:
1647 	case CP210X_PARTNUM_CP2102N_QFN24:
1648 	case CP210X_PARTNUM_CP2102N_QFN20:
1649 		result = cp2102n_gpioconf_init(serial);
1650 		break;
1651 	default:
1652 		return 0;
1653 	}
1654 
1655 	if (result < 0)
1656 		return result;
1657 
1658 	priv->gc.label = "cp210x";
1659 	priv->gc.request = cp210x_gpio_request;
1660 	priv->gc.get_direction = cp210x_gpio_direction_get;
1661 	priv->gc.direction_input = cp210x_gpio_direction_input;
1662 	priv->gc.direction_output = cp210x_gpio_direction_output;
1663 	priv->gc.get = cp210x_gpio_get;
1664 	priv->gc.set = cp210x_gpio_set;
1665 	priv->gc.set_config = cp210x_gpio_set_config;
1666 	priv->gc.owner = THIS_MODULE;
1667 	priv->gc.parent = &serial->interface->dev;
1668 	priv->gc.base = -1;
1669 	priv->gc.can_sleep = true;
1670 
1671 	result = gpiochip_add_data(&priv->gc, serial);
1672 	if (!result)
1673 		priv->gpio_registered = true;
1674 
1675 	return result;
1676 }
1677 
1678 static void cp210x_gpio_remove(struct usb_serial *serial)
1679 {
1680 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1681 
1682 	if (priv->gpio_registered) {
1683 		gpiochip_remove(&priv->gc);
1684 		priv->gpio_registered = false;
1685 	}
1686 }
1687 
1688 #else
1689 
1690 static int cp210x_gpio_init(struct usb_serial *serial)
1691 {
1692 	return 0;
1693 }
1694 
1695 static void cp210x_gpio_remove(struct usb_serial *serial)
1696 {
1697 	/* Nothing to do */
1698 }
1699 
1700 #endif
1701 
1702 static int cp210x_port_probe(struct usb_serial_port *port)
1703 {
1704 	struct usb_serial *serial = port->serial;
1705 	struct cp210x_port_private *port_priv;
1706 
1707 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1708 	if (!port_priv)
1709 		return -ENOMEM;
1710 
1711 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1712 
1713 	usb_set_serial_port_data(port, port_priv);
1714 
1715 	return 0;
1716 }
1717 
1718 static int cp210x_port_remove(struct usb_serial_port *port)
1719 {
1720 	struct cp210x_port_private *port_priv;
1721 
1722 	port_priv = usb_get_serial_port_data(port);
1723 	kfree(port_priv);
1724 
1725 	return 0;
1726 }
1727 
1728 static void cp210x_init_max_speed(struct usb_serial *serial)
1729 {
1730 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1731 	bool use_actual_rate = false;
1732 	speed_t min = 300;
1733 	speed_t max;
1734 
1735 	switch (priv->partnum) {
1736 	case CP210X_PARTNUM_CP2101:
1737 		max = 921600;
1738 		break;
1739 	case CP210X_PARTNUM_CP2102:
1740 	case CP210X_PARTNUM_CP2103:
1741 		max = 1000000;
1742 		break;
1743 	case CP210X_PARTNUM_CP2104:
1744 		use_actual_rate = true;
1745 		max = 2000000;
1746 		break;
1747 	case CP210X_PARTNUM_CP2108:
1748 		max = 2000000;
1749 		break;
1750 	case CP210X_PARTNUM_CP2105:
1751 		if (cp210x_interface_num(serial) == 0) {
1752 			use_actual_rate = true;
1753 			max = 2000000;	/* ECI */
1754 		} else {
1755 			min = 2400;
1756 			max = 921600;	/* SCI */
1757 		}
1758 		break;
1759 	case CP210X_PARTNUM_CP2102N_QFN28:
1760 	case CP210X_PARTNUM_CP2102N_QFN24:
1761 	case CP210X_PARTNUM_CP2102N_QFN20:
1762 		use_actual_rate = true;
1763 		max = 3000000;
1764 		break;
1765 	default:
1766 		max = 2000000;
1767 		break;
1768 	}
1769 
1770 	priv->min_speed = min;
1771 	priv->max_speed = max;
1772 	priv->use_actual_rate = use_actual_rate;
1773 }
1774 
1775 static int cp210x_attach(struct usb_serial *serial)
1776 {
1777 	int result;
1778 	struct cp210x_serial_private *priv;
1779 
1780 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1781 	if (!priv)
1782 		return -ENOMEM;
1783 
1784 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1785 					  CP210X_GET_PARTNUM, &priv->partnum,
1786 					  sizeof(priv->partnum));
1787 	if (result < 0) {
1788 		dev_warn(&serial->interface->dev,
1789 			 "querying part number failed\n");
1790 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1791 	}
1792 
1793 	usb_set_serial_data(serial, priv);
1794 
1795 	cp210x_init_max_speed(serial);
1796 
1797 	result = cp210x_gpio_init(serial);
1798 	if (result < 0) {
1799 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1800 				result);
1801 	}
1802 
1803 	return 0;
1804 }
1805 
1806 static void cp210x_disconnect(struct usb_serial *serial)
1807 {
1808 	cp210x_gpio_remove(serial);
1809 }
1810 
1811 static void cp210x_release(struct usb_serial *serial)
1812 {
1813 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1814 
1815 	cp210x_gpio_remove(serial);
1816 
1817 	kfree(priv);
1818 }
1819 
1820 module_usb_serial_driver(serial_drivers, id_table);
1821 
1822 MODULE_DESCRIPTION(DRIVER_DESC);
1823 MODULE_LICENSE("GPL v2");
1824