xref: /linux/drivers/usb/serial/cp210x.c (revision 7748feffcd80f3ee25dae5e6acd3cf90e8e838d8)
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(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(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
205 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
206 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
207 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
208 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
209 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
210 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
211 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
212 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
213 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
214 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
215 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
216 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
217 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
218 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
219 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
220 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
221 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
222 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
227 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
228 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
229 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
230 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
231 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
232 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
233 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
234 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
235 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
236 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
237 	{ } /* Terminating Entry */
238 };
239 
240 MODULE_DEVICE_TABLE(usb, id_table);
241 
242 struct cp210x_serial_private {
243 #ifdef CONFIG_GPIOLIB
244 	struct gpio_chip	gc;
245 	bool			gpio_registered;
246 	u8			gpio_pushpull;
247 	u8			gpio_altfunc;
248 	u8			gpio_input;
249 #endif
250 	u8			partnum;
251 	speed_t			min_speed;
252 	speed_t			max_speed;
253 	bool			use_actual_rate;
254 };
255 
256 enum cp210x_event_state {
257 	ES_DATA,
258 	ES_ESCAPE,
259 	ES_LSR,
260 	ES_LSR_DATA_0,
261 	ES_LSR_DATA_1,
262 	ES_MSR
263 };
264 
265 struct cp210x_port_private {
266 	u8			bInterfaceNumber;
267 	bool			event_mode;
268 	enum cp210x_event_state event_state;
269 	u8 lsr;
270 };
271 
272 static struct usb_serial_driver cp210x_device = {
273 	.driver = {
274 		.owner =	THIS_MODULE,
275 		.name =		"cp210x",
276 	},
277 	.id_table		= id_table,
278 	.num_ports		= 1,
279 	.bulk_in_size		= 256,
280 	.bulk_out_size		= 256,
281 	.open			= cp210x_open,
282 	.close			= cp210x_close,
283 	.break_ctl		= cp210x_break_ctl,
284 	.set_termios		= cp210x_set_termios,
285 	.tx_empty		= cp210x_tx_empty,
286 	.throttle		= usb_serial_generic_throttle,
287 	.unthrottle		= usb_serial_generic_unthrottle,
288 	.tiocmget		= cp210x_tiocmget,
289 	.tiocmset		= cp210x_tiocmset,
290 	.get_icount		= usb_serial_generic_get_icount,
291 	.attach			= cp210x_attach,
292 	.disconnect		= cp210x_disconnect,
293 	.release		= cp210x_release,
294 	.port_probe		= cp210x_port_probe,
295 	.port_remove		= cp210x_port_remove,
296 	.dtr_rts		= cp210x_dtr_rts,
297 	.process_read_urb	= cp210x_process_read_urb,
298 };
299 
300 static struct usb_serial_driver * const serial_drivers[] = {
301 	&cp210x_device, NULL
302 };
303 
304 /* Config request types */
305 #define REQTYPE_HOST_TO_INTERFACE	0x41
306 #define REQTYPE_INTERFACE_TO_HOST	0xc1
307 #define REQTYPE_HOST_TO_DEVICE	0x40
308 #define REQTYPE_DEVICE_TO_HOST	0xc0
309 
310 /* Config request codes */
311 #define CP210X_IFC_ENABLE	0x00
312 #define CP210X_SET_BAUDDIV	0x01
313 #define CP210X_GET_BAUDDIV	0x02
314 #define CP210X_SET_LINE_CTL	0x03
315 #define CP210X_GET_LINE_CTL	0x04
316 #define CP210X_SET_BREAK	0x05
317 #define CP210X_IMM_CHAR		0x06
318 #define CP210X_SET_MHS		0x07
319 #define CP210X_GET_MDMSTS	0x08
320 #define CP210X_SET_XON		0x09
321 #define CP210X_SET_XOFF		0x0A
322 #define CP210X_SET_EVENTMASK	0x0B
323 #define CP210X_GET_EVENTMASK	0x0C
324 #define CP210X_SET_CHAR		0x0D
325 #define CP210X_GET_CHARS	0x0E
326 #define CP210X_GET_PROPS	0x0F
327 #define CP210X_GET_COMM_STATUS	0x10
328 #define CP210X_RESET		0x11
329 #define CP210X_PURGE		0x12
330 #define CP210X_SET_FLOW		0x13
331 #define CP210X_GET_FLOW		0x14
332 #define CP210X_EMBED_EVENTS	0x15
333 #define CP210X_GET_EVENTSTATE	0x16
334 #define CP210X_SET_CHARS	0x19
335 #define CP210X_GET_BAUDRATE	0x1D
336 #define CP210X_SET_BAUDRATE	0x1E
337 #define CP210X_VENDOR_SPECIFIC	0xFF
338 
339 /* CP210X_IFC_ENABLE */
340 #define UART_ENABLE		0x0001
341 #define UART_DISABLE		0x0000
342 
343 /* CP210X_(SET|GET)_BAUDDIV */
344 #define BAUD_RATE_GEN_FREQ	0x384000
345 
346 /* CP210X_(SET|GET)_LINE_CTL */
347 #define BITS_DATA_MASK		0X0f00
348 #define BITS_DATA_5		0X0500
349 #define BITS_DATA_6		0X0600
350 #define BITS_DATA_7		0X0700
351 #define BITS_DATA_8		0X0800
352 #define BITS_DATA_9		0X0900
353 
354 #define BITS_PARITY_MASK	0x00f0
355 #define BITS_PARITY_NONE	0x0000
356 #define BITS_PARITY_ODD		0x0010
357 #define BITS_PARITY_EVEN	0x0020
358 #define BITS_PARITY_MARK	0x0030
359 #define BITS_PARITY_SPACE	0x0040
360 
361 #define BITS_STOP_MASK		0x000f
362 #define BITS_STOP_1		0x0000
363 #define BITS_STOP_1_5		0x0001
364 #define BITS_STOP_2		0x0002
365 
366 /* CP210X_SET_BREAK */
367 #define BREAK_ON		0x0001
368 #define BREAK_OFF		0x0000
369 
370 /* CP210X_(SET_MHS|GET_MDMSTS) */
371 #define CONTROL_DTR		0x0001
372 #define CONTROL_RTS		0x0002
373 #define CONTROL_CTS		0x0010
374 #define CONTROL_DSR		0x0020
375 #define CONTROL_RING		0x0040
376 #define CONTROL_DCD		0x0080
377 #define CONTROL_WRITE_DTR	0x0100
378 #define CONTROL_WRITE_RTS	0x0200
379 
380 /* CP210X_(GET|SET)_CHARS */
381 struct cp210x_special_chars {
382 	u8	bEofChar;
383 	u8	bErrorChar;
384 	u8	bBreakChar;
385 	u8	bEventChar;
386 	u8	bXonChar;
387 	u8	bXoffChar;
388 };
389 
390 /* CP210X_VENDOR_SPECIFIC values */
391 #define CP210X_READ_2NCONFIG	0x000E
392 #define CP210X_READ_LATCH	0x00C2
393 #define CP210X_GET_PARTNUM	0x370B
394 #define CP210X_GET_PORTCONFIG	0x370C
395 #define CP210X_GET_DEVICEMODE	0x3711
396 #define CP210X_WRITE_LATCH	0x37E1
397 
398 /* Part number definitions */
399 #define CP210X_PARTNUM_CP2101	0x01
400 #define CP210X_PARTNUM_CP2102	0x02
401 #define CP210X_PARTNUM_CP2103	0x03
402 #define CP210X_PARTNUM_CP2104	0x04
403 #define CP210X_PARTNUM_CP2105	0x05
404 #define CP210X_PARTNUM_CP2108	0x08
405 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
406 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
407 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
408 #define CP210X_PARTNUM_UNKNOWN	0xFF
409 
410 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
411 struct cp210x_comm_status {
412 	__le32   ulErrors;
413 	__le32   ulHoldReasons;
414 	__le32   ulAmountInInQueue;
415 	__le32   ulAmountInOutQueue;
416 	u8       bEofReceived;
417 	u8       bWaitForImmediate;
418 	u8       bReserved;
419 } __packed;
420 
421 /*
422  * CP210X_PURGE - 16 bits passed in wValue of USB request.
423  * SiLabs app note AN571 gives a strange description of the 4 bits:
424  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
425  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
426  */
427 #define PURGE_ALL		0x000f
428 
429 /* CP210X_EMBED_EVENTS */
430 #define CP210X_ESCCHAR		0xec
431 
432 #define CP210X_LSR_OVERRUN	BIT(1)
433 #define CP210X_LSR_PARITY	BIT(2)
434 #define CP210X_LSR_FRAME	BIT(3)
435 #define CP210X_LSR_BREAK	BIT(4)
436 
437 
438 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
439 struct cp210x_flow_ctl {
440 	__le32	ulControlHandshake;
441 	__le32	ulFlowReplace;
442 	__le32	ulXonLimit;
443 	__le32	ulXoffLimit;
444 };
445 
446 /* cp210x_flow_ctl::ulControlHandshake */
447 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
448 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
449 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
450 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
451 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
452 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
453 
454 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
455 #define CP210X_SERIAL_DTR_INACTIVE	0
456 #define CP210X_SERIAL_DTR_ACTIVE	1
457 #define CP210X_SERIAL_DTR_FLOW_CTL	2
458 
459 /* cp210x_flow_ctl::ulFlowReplace */
460 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
461 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
462 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
463 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
464 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
465 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
466 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
467 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
468 
469 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
470 #define CP210X_SERIAL_RTS_INACTIVE	0
471 #define CP210X_SERIAL_RTS_ACTIVE	1
472 #define CP210X_SERIAL_RTS_FLOW_CTL	2
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 == bufsize) {
678 		result = 0;
679 	} else {
680 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
681 				req, bufsize, result);
682 		if (result >= 0)
683 			result = -EIO;
684 	}
685 
686 	return result;
687 }
688 
689 /*
690  * Writes any 32-bit CP210X_ register identified by req.
691  */
692 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
693 {
694 	__le32 le32_val;
695 
696 	le32_val = cpu_to_le32(val);
697 
698 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
699 }
700 
701 #ifdef CONFIG_GPIOLIB
702 /*
703  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
704  * Data in buf must be in native USB byte order.
705  */
706 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
707 				     u16 val, void *buf, int bufsize)
708 {
709 	void *dmabuf;
710 	int result;
711 
712 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
713 	if (!dmabuf)
714 		return -ENOMEM;
715 
716 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
717 				 CP210X_VENDOR_SPECIFIC, type, val,
718 				 cp210x_interface_num(serial), dmabuf, bufsize,
719 				 USB_CTRL_SET_TIMEOUT);
720 
721 	kfree(dmabuf);
722 
723 	if (result == bufsize) {
724 		result = 0;
725 	} else {
726 		dev_err(&serial->interface->dev,
727 			"failed to set vendor val 0x%04x size %d: %d\n", val,
728 			bufsize, result);
729 		if (result >= 0)
730 			result = -EIO;
731 	}
732 
733 	return result;
734 }
735 #endif
736 
737 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
738 {
739 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
740 	int result;
741 
742 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
743 	if (result) {
744 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
745 		return result;
746 	}
747 
748 	if (tty)
749 		cp210x_set_termios(tty, port, NULL);
750 
751 	result = usb_serial_generic_open(tty, port);
752 	if (result)
753 		goto err_disable;
754 
755 	return 0;
756 
757 err_disable:
758 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
759 	port_priv->event_mode = false;
760 
761 	return result;
762 }
763 
764 static void cp210x_close(struct usb_serial_port *port)
765 {
766 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
767 
768 	usb_serial_generic_close(port);
769 
770 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
771 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
772 
773 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
774 
775 	/* Disabling the interface disables event-insertion mode. */
776 	port_priv->event_mode = false;
777 }
778 
779 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
780 {
781 	if (lsr & CP210X_LSR_BREAK) {
782 		port->icount.brk++;
783 		*flag = TTY_BREAK;
784 	} else if (lsr & CP210X_LSR_PARITY) {
785 		port->icount.parity++;
786 		*flag = TTY_PARITY;
787 	} else if (lsr & CP210X_LSR_FRAME) {
788 		port->icount.frame++;
789 		*flag = TTY_FRAME;
790 	}
791 
792 	if (lsr & CP210X_LSR_OVERRUN) {
793 		port->icount.overrun++;
794 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
795 	}
796 }
797 
798 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
799 {
800 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
801 
802 	switch (port_priv->event_state) {
803 	case ES_DATA:
804 		if (*ch == CP210X_ESCCHAR) {
805 			port_priv->event_state = ES_ESCAPE;
806 			break;
807 		}
808 		return false;
809 	case ES_ESCAPE:
810 		switch (*ch) {
811 		case 0:
812 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
813 			*ch = CP210X_ESCCHAR;
814 			port_priv->event_state = ES_DATA;
815 			return false;
816 		case 1:
817 			port_priv->event_state = ES_LSR_DATA_0;
818 			break;
819 		case 2:
820 			port_priv->event_state = ES_LSR;
821 			break;
822 		case 3:
823 			port_priv->event_state = ES_MSR;
824 			break;
825 		default:
826 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
827 			port_priv->event_state = ES_DATA;
828 			break;
829 		}
830 		break;
831 	case ES_LSR_DATA_0:
832 		port_priv->lsr = *ch;
833 		port_priv->event_state = ES_LSR_DATA_1;
834 		break;
835 	case ES_LSR_DATA_1:
836 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
837 				__func__, port_priv->lsr, *ch);
838 		cp210x_process_lsr(port, port_priv->lsr, flag);
839 		port_priv->event_state = ES_DATA;
840 		return false;
841 	case ES_LSR:
842 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
843 		port_priv->lsr = *ch;
844 		cp210x_process_lsr(port, port_priv->lsr, flag);
845 		port_priv->event_state = ES_DATA;
846 		break;
847 	case ES_MSR:
848 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
849 		/* unimplemented */
850 		port_priv->event_state = ES_DATA;
851 		break;
852 	}
853 
854 	return true;
855 }
856 
857 static void cp210x_process_read_urb(struct urb *urb)
858 {
859 	struct usb_serial_port *port = urb->context;
860 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
861 	unsigned char *ch = urb->transfer_buffer;
862 	char flag;
863 	int i;
864 
865 	if (!urb->actual_length)
866 		return;
867 
868 	if (port_priv->event_mode) {
869 		for (i = 0; i < urb->actual_length; i++, ch++) {
870 			flag = TTY_NORMAL;
871 
872 			if (cp210x_process_char(port, ch, &flag))
873 				continue;
874 
875 			tty_insert_flip_char(&port->port, *ch, flag);
876 		}
877 	} else {
878 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
879 	}
880 	tty_flip_buffer_push(&port->port);
881 }
882 
883 /*
884  * Read how many bytes are waiting in the TX queue.
885  */
886 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
887 		u32 *count)
888 {
889 	struct usb_serial *serial = port->serial;
890 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
891 	struct cp210x_comm_status *sts;
892 	int result;
893 
894 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
895 	if (!sts)
896 		return -ENOMEM;
897 
898 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
899 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
900 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
901 			USB_CTRL_GET_TIMEOUT);
902 	if (result == sizeof(*sts)) {
903 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
904 		result = 0;
905 	} else {
906 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
907 		if (result >= 0)
908 			result = -EIO;
909 	}
910 
911 	kfree(sts);
912 
913 	return result;
914 }
915 
916 static bool cp210x_tx_empty(struct usb_serial_port *port)
917 {
918 	int err;
919 	u32 count;
920 
921 	err = cp210x_get_tx_queue_byte_count(port, &count);
922 	if (err)
923 		return true;
924 
925 	return !count;
926 }
927 
928 struct cp210x_rate {
929 	speed_t rate;
930 	speed_t high;
931 };
932 
933 static const struct cp210x_rate cp210x_an205_table1[] = {
934 	{ 300, 300 },
935 	{ 600, 600 },
936 	{ 1200, 1200 },
937 	{ 1800, 1800 },
938 	{ 2400, 2400 },
939 	{ 4000, 4000 },
940 	{ 4800, 4803 },
941 	{ 7200, 7207 },
942 	{ 9600, 9612 },
943 	{ 14400, 14428 },
944 	{ 16000, 16062 },
945 	{ 19200, 19250 },
946 	{ 28800, 28912 },
947 	{ 38400, 38601 },
948 	{ 51200, 51558 },
949 	{ 56000, 56280 },
950 	{ 57600, 58053 },
951 	{ 64000, 64111 },
952 	{ 76800, 77608 },
953 	{ 115200, 117028 },
954 	{ 128000, 129347 },
955 	{ 153600, 156868 },
956 	{ 230400, 237832 },
957 	{ 250000, 254234 },
958 	{ 256000, 273066 },
959 	{ 460800, 491520 },
960 	{ 500000, 567138 },
961 	{ 576000, 670254 },
962 	{ 921600, UINT_MAX }
963 };
964 
965 /*
966  * Quantises the baud rate as per AN205 Table 1
967  */
968 static speed_t cp210x_get_an205_rate(speed_t baud)
969 {
970 	int i;
971 
972 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
973 		if (baud <= cp210x_an205_table1[i].high)
974 			break;
975 	}
976 
977 	return cp210x_an205_table1[i].rate;
978 }
979 
980 static speed_t cp210x_get_actual_rate(speed_t baud)
981 {
982 	unsigned int prescale = 1;
983 	unsigned int div;
984 
985 	if (baud <= 365)
986 		prescale = 4;
987 
988 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
989 	baud = 48000000 / (2 * prescale * div);
990 
991 	return baud;
992 }
993 
994 /*
995  * CP2101 supports the following baud rates:
996  *
997  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
998  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
999  *
1000  * CP2102 and CP2103 support the following additional rates:
1001  *
1002  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1003  *	576000
1004  *
1005  * The device will map a requested rate to a supported one, but the result
1006  * of requests for rates greater than 1053257 is undefined (see AN205).
1007  *
1008  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1009  * respectively, with an error less than 1%. The actual rates are determined
1010  * by
1011  *
1012  *	div = round(freq / (2 x prescale x request))
1013  *	actual = freq / (2 x prescale x div)
1014  *
1015  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1016  * or 1 otherwise.
1017  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1018  * otherwise.
1019  */
1020 static void cp210x_change_speed(struct tty_struct *tty,
1021 		struct usb_serial_port *port, struct ktermios *old_termios)
1022 {
1023 	struct usb_serial *serial = port->serial;
1024 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1025 	u32 baud;
1026 
1027 	/*
1028 	 * This maps the requested rate to the actual rate, a valid rate on
1029 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1030 	 *
1031 	 * NOTE: B0 is not implemented.
1032 	 */
1033 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1034 
1035 	if (priv->use_actual_rate)
1036 		baud = cp210x_get_actual_rate(baud);
1037 	else if (baud < 1000000)
1038 		baud = cp210x_get_an205_rate(baud);
1039 
1040 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1041 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1042 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1043 		if (old_termios)
1044 			baud = old_termios->c_ospeed;
1045 		else
1046 			baud = 9600;
1047 	}
1048 
1049 	tty_encode_baud_rate(tty, baud, baud);
1050 }
1051 
1052 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1053 {
1054 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1055 	int ret;
1056 
1057 	if (port_priv->event_mode)
1058 		return;
1059 
1060 	port_priv->event_state = ES_DATA;
1061 	port_priv->event_mode = true;
1062 
1063 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1064 	if (ret) {
1065 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1066 		port_priv->event_mode = false;
1067 	}
1068 }
1069 
1070 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1071 {
1072 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1073 	int ret;
1074 
1075 	if (!port_priv->event_mode)
1076 		return;
1077 
1078 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1079 	if (ret) {
1080 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1081 		return;
1082 	}
1083 
1084 	port_priv->event_mode = false;
1085 }
1086 
1087 static int cp210x_set_chars(struct usb_serial_port *port,
1088 		struct cp210x_special_chars *chars)
1089 {
1090 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1091 	struct usb_serial *serial = port->serial;
1092 	void *dmabuf;
1093 	int result;
1094 
1095 	dmabuf = kmemdup(chars, sizeof(*chars), GFP_KERNEL);
1096 	if (!dmabuf)
1097 		return -ENOMEM;
1098 
1099 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1100 				CP210X_SET_CHARS, REQTYPE_HOST_TO_INTERFACE, 0,
1101 				port_priv->bInterfaceNumber,
1102 				dmabuf, sizeof(*chars), USB_CTRL_SET_TIMEOUT);
1103 
1104 	kfree(dmabuf);
1105 
1106 	if (result < 0) {
1107 		dev_err(&port->dev, "failed to set special chars: %d\n", result);
1108 		return result;
1109 	}
1110 
1111 	return 0;
1112 }
1113 
1114 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1115 {
1116 	bool iflag_change;
1117 
1118 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1119 
1120 	return tty_termios_hw_change(a, b) || iflag_change;
1121 }
1122 
1123 static void cp210x_set_flow_control(struct tty_struct *tty,
1124 		struct usb_serial_port *port, struct ktermios *old_termios)
1125 {
1126 	struct cp210x_special_chars chars;
1127 	struct cp210x_flow_ctl flow_ctl;
1128 	u32 flow_repl;
1129 	u32 ctl_hs;
1130 	int ret;
1131 
1132 	if (old_termios &&
1133 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1134 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1135 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF)) {
1136 		return;
1137 	}
1138 
1139 	if (I_IXON(tty) || I_IXOFF(tty)) {
1140 		memset(&chars, 0, sizeof(chars));
1141 
1142 		chars.bXonChar = START_CHAR(tty);
1143 		chars.bXoffChar = STOP_CHAR(tty);
1144 
1145 		ret = cp210x_set_chars(port, &chars);
1146 		if (ret)
1147 			return;
1148 	}
1149 
1150 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1151 			sizeof(flow_ctl));
1152 	if (ret)
1153 		return;
1154 
1155 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1156 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1157 
1158 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1159 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1160 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1161 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1162 	ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1163 
1164 	if (C_CRTSCTS(tty)) {
1165 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1166 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1167 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
1168 	} else {
1169 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1170 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1171 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_ACTIVE);
1172 	}
1173 
1174 	if (I_IXOFF(tty))
1175 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1176 	else
1177 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1178 
1179 	if (I_IXON(tty))
1180 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1181 	else
1182 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1183 
1184 	dev_dbg(&port->dev, "%s - ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1185 			__func__, ctl_hs, flow_repl);
1186 
1187 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1188 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1189 
1190 	cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1191 			sizeof(flow_ctl));
1192 }
1193 
1194 static void cp210x_set_termios(struct tty_struct *tty,
1195 		struct usb_serial_port *port, struct ktermios *old_termios)
1196 {
1197 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1198 	u16 bits;
1199 	int ret;
1200 
1201 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1202 		return;
1203 
1204 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1205 		cp210x_change_speed(tty, port, old_termios);
1206 
1207 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1208 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1209 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1210 		tty->termios.c_cflag |= CS8;
1211 	}
1212 
1213 	bits = 0;
1214 
1215 	switch (C_CSIZE(tty)) {
1216 	case CS5:
1217 		bits |= BITS_DATA_5;
1218 		break;
1219 	case CS6:
1220 		bits |= BITS_DATA_6;
1221 		break;
1222 	case CS7:
1223 		bits |= BITS_DATA_7;
1224 		break;
1225 	case CS8:
1226 	default:
1227 		bits |= BITS_DATA_8;
1228 		break;
1229 	}
1230 
1231 	if (C_PARENB(tty)) {
1232 		if (C_CMSPAR(tty)) {
1233 			if (C_PARODD(tty))
1234 				bits |= BITS_PARITY_MARK;
1235 			else
1236 				bits |= BITS_PARITY_SPACE;
1237 		} else {
1238 			if (C_PARODD(tty))
1239 				bits |= BITS_PARITY_ODD;
1240 			else
1241 				bits |= BITS_PARITY_EVEN;
1242 		}
1243 	}
1244 
1245 	if (C_CSTOPB(tty))
1246 		bits |= BITS_STOP_2;
1247 	else
1248 		bits |= BITS_STOP_1;
1249 
1250 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1251 	if (ret)
1252 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1253 
1254 	cp210x_set_flow_control(tty, port, old_termios);
1255 
1256 	/*
1257 	 * Enable event-insertion mode only if input parity checking is
1258 	 * enabled for now.
1259 	 */
1260 	if (I_INPCK(tty))
1261 		cp210x_enable_event_mode(port);
1262 	else
1263 		cp210x_disable_event_mode(port);
1264 }
1265 
1266 static int cp210x_tiocmset(struct tty_struct *tty,
1267 		unsigned int set, unsigned int clear)
1268 {
1269 	struct usb_serial_port *port = tty->driver_data;
1270 	return cp210x_tiocmset_port(port, set, clear);
1271 }
1272 
1273 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1274 		unsigned int set, unsigned int clear)
1275 {
1276 	u16 control = 0;
1277 
1278 	if (set & TIOCM_RTS) {
1279 		control |= CONTROL_RTS;
1280 		control |= CONTROL_WRITE_RTS;
1281 	}
1282 	if (set & TIOCM_DTR) {
1283 		control |= CONTROL_DTR;
1284 		control |= CONTROL_WRITE_DTR;
1285 	}
1286 	if (clear & TIOCM_RTS) {
1287 		control &= ~CONTROL_RTS;
1288 		control |= CONTROL_WRITE_RTS;
1289 	}
1290 	if (clear & TIOCM_DTR) {
1291 		control &= ~CONTROL_DTR;
1292 		control |= CONTROL_WRITE_DTR;
1293 	}
1294 
1295 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1296 
1297 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1298 }
1299 
1300 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1301 {
1302 	if (on)
1303 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1304 	else
1305 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1306 }
1307 
1308 static int cp210x_tiocmget(struct tty_struct *tty)
1309 {
1310 	struct usb_serial_port *port = tty->driver_data;
1311 	u8 control;
1312 	int result;
1313 
1314 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1315 	if (result)
1316 		return result;
1317 
1318 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1319 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1320 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1321 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1322 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1323 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1324 
1325 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1326 
1327 	return result;
1328 }
1329 
1330 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1331 {
1332 	struct usb_serial_port *port = tty->driver_data;
1333 	u16 state;
1334 
1335 	if (break_state == 0)
1336 		state = BREAK_OFF;
1337 	else
1338 		state = BREAK_ON;
1339 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1340 		state == BREAK_OFF ? "off" : "on");
1341 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1342 }
1343 
1344 #ifdef CONFIG_GPIOLIB
1345 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1346 {
1347 	struct usb_serial *serial = gpiochip_get_data(gc);
1348 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1349 
1350 	if (priv->gpio_altfunc & BIT(offset))
1351 		return -ENODEV;
1352 
1353 	return 0;
1354 }
1355 
1356 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1357 {
1358 	struct usb_serial *serial = gpiochip_get_data(gc);
1359 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1360 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1361 	int result;
1362 	u8 buf;
1363 
1364 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1365 		req_type = REQTYPE_INTERFACE_TO_HOST;
1366 
1367 	result = usb_autopm_get_interface(serial->interface);
1368 	if (result)
1369 		return result;
1370 
1371 	result = cp210x_read_vendor_block(serial, req_type,
1372 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1373 	usb_autopm_put_interface(serial->interface);
1374 	if (result < 0)
1375 		return result;
1376 
1377 	return !!(buf & BIT(gpio));
1378 }
1379 
1380 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1381 {
1382 	struct usb_serial *serial = gpiochip_get_data(gc);
1383 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1384 	struct cp210x_gpio_write buf;
1385 	int result;
1386 
1387 	if (value == 1)
1388 		buf.state = BIT(gpio);
1389 	else
1390 		buf.state = 0;
1391 
1392 	buf.mask = BIT(gpio);
1393 
1394 	result = usb_autopm_get_interface(serial->interface);
1395 	if (result)
1396 		goto out;
1397 
1398 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1399 		result = cp210x_write_vendor_block(serial,
1400 						   REQTYPE_HOST_TO_INTERFACE,
1401 						   CP210X_WRITE_LATCH, &buf,
1402 						   sizeof(buf));
1403 	} else {
1404 		u16 wIndex = buf.state << 8 | buf.mask;
1405 
1406 		result = usb_control_msg(serial->dev,
1407 					 usb_sndctrlpipe(serial->dev, 0),
1408 					 CP210X_VENDOR_SPECIFIC,
1409 					 REQTYPE_HOST_TO_DEVICE,
1410 					 CP210X_WRITE_LATCH,
1411 					 wIndex,
1412 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1413 	}
1414 
1415 	usb_autopm_put_interface(serial->interface);
1416 out:
1417 	if (result < 0) {
1418 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1419 				result);
1420 	}
1421 }
1422 
1423 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1424 {
1425 	struct usb_serial *serial = gpiochip_get_data(gc);
1426 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1427 
1428 	return priv->gpio_input & BIT(gpio);
1429 }
1430 
1431 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1432 {
1433 	struct usb_serial *serial = gpiochip_get_data(gc);
1434 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1435 
1436 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1437 		/* hardware does not support an input mode */
1438 		return -ENOTSUPP;
1439 	}
1440 
1441 	/* push-pull pins cannot be changed to be inputs */
1442 	if (priv->gpio_pushpull & BIT(gpio))
1443 		return -EINVAL;
1444 
1445 	/* make sure to release pin if it is being driven low */
1446 	cp210x_gpio_set(gc, gpio, 1);
1447 
1448 	priv->gpio_input |= BIT(gpio);
1449 
1450 	return 0;
1451 }
1452 
1453 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1454 					int value)
1455 {
1456 	struct usb_serial *serial = gpiochip_get_data(gc);
1457 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1458 
1459 	priv->gpio_input &= ~BIT(gpio);
1460 	cp210x_gpio_set(gc, gpio, value);
1461 
1462 	return 0;
1463 }
1464 
1465 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1466 				  unsigned long config)
1467 {
1468 	struct usb_serial *serial = gpiochip_get_data(gc);
1469 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1470 	enum pin_config_param param = pinconf_to_config_param(config);
1471 
1472 	/* Succeed only if in correct mode (this can't be set at runtime) */
1473 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1474 	    (priv->gpio_pushpull & BIT(gpio)))
1475 		return 0;
1476 
1477 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1478 	    !(priv->gpio_pushpull & BIT(gpio)))
1479 		return 0;
1480 
1481 	return -ENOTSUPP;
1482 }
1483 
1484 /*
1485  * This function is for configuring GPIO using shared pins, where other signals
1486  * are made unavailable by configuring the use of GPIO. This is believed to be
1487  * only applicable to the cp2105 at this point, the other devices supported by
1488  * this driver that provide GPIO do so in a way that does not impact other
1489  * signals and are thus expected to have very different initialisation.
1490  */
1491 static int cp2105_gpioconf_init(struct usb_serial *serial)
1492 {
1493 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1494 	struct cp210x_pin_mode mode;
1495 	struct cp210x_dual_port_config config;
1496 	u8 intf_num = cp210x_interface_num(serial);
1497 	u8 iface_config;
1498 	int result;
1499 
1500 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1501 					  CP210X_GET_DEVICEMODE, &mode,
1502 					  sizeof(mode));
1503 	if (result < 0)
1504 		return result;
1505 
1506 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1507 					  CP210X_GET_PORTCONFIG, &config,
1508 					  sizeof(config));
1509 	if (result < 0)
1510 		return result;
1511 
1512 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1513 	if (intf_num == 0) {
1514 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1515 			/* mark all GPIOs of this interface as reserved */
1516 			priv->gpio_altfunc = 0xff;
1517 			return 0;
1518 		}
1519 
1520 		iface_config = config.eci_cfg;
1521 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1522 						CP210X_ECI_GPIO_MODE_MASK) >>
1523 						CP210X_ECI_GPIO_MODE_OFFSET);
1524 		priv->gc.ngpio = 2;
1525 	} else if (intf_num == 1) {
1526 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1527 			/* mark all GPIOs of this interface as reserved */
1528 			priv->gpio_altfunc = 0xff;
1529 			return 0;
1530 		}
1531 
1532 		iface_config = config.sci_cfg;
1533 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1534 						CP210X_SCI_GPIO_MODE_MASK) >>
1535 						CP210X_SCI_GPIO_MODE_OFFSET);
1536 		priv->gc.ngpio = 3;
1537 	} else {
1538 		return -ENODEV;
1539 	}
1540 
1541 	/* mark all pins which are not in GPIO mode */
1542 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1543 		priv->gpio_altfunc |= BIT(0);
1544 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1545 			CP2105_GPIO1_RS485_MODE))
1546 		priv->gpio_altfunc |= BIT(1);
1547 
1548 	/* driver implementation for CP2105 only supports outputs */
1549 	priv->gpio_input = 0;
1550 
1551 	return 0;
1552 }
1553 
1554 static int cp2104_gpioconf_init(struct usb_serial *serial)
1555 {
1556 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1557 	struct cp210x_single_port_config config;
1558 	u8 iface_config;
1559 	u8 gpio_latch;
1560 	int result;
1561 	u8 i;
1562 
1563 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1564 					  CP210X_GET_PORTCONFIG, &config,
1565 					  sizeof(config));
1566 	if (result < 0)
1567 		return result;
1568 
1569 	priv->gc.ngpio = 4;
1570 
1571 	iface_config = config.device_cfg;
1572 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1573 					CP210X_GPIO_MODE_MASK) >>
1574 					CP210X_GPIO_MODE_OFFSET);
1575 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1576 					CP210X_GPIO_MODE_MASK) >>
1577 					CP210X_GPIO_MODE_OFFSET);
1578 
1579 	/* mark all pins which are not in GPIO mode */
1580 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1581 		priv->gpio_altfunc |= BIT(0);
1582 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1583 		priv->gpio_altfunc |= BIT(1);
1584 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1585 		priv->gpio_altfunc |= BIT(2);
1586 
1587 	/*
1588 	 * Like CP2102N, CP2104 has also no strict input and output pin
1589 	 * modes.
1590 	 * Do the same input mode emulation as CP2102N.
1591 	 */
1592 	for (i = 0; i < priv->gc.ngpio; ++i) {
1593 		/*
1594 		 * Set direction to "input" iff pin is open-drain and reset
1595 		 * value is 1.
1596 		 */
1597 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1598 			priv->gpio_input |= BIT(i);
1599 	}
1600 
1601 	return 0;
1602 }
1603 
1604 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1605 {
1606 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1607 	const u16 config_size = 0x02a6;
1608 	u8 gpio_rst_latch;
1609 	u8 config_version;
1610 	u8 gpio_pushpull;
1611 	u8 *config_buf;
1612 	u8 gpio_latch;
1613 	u8 gpio_ctrl;
1614 	int result;
1615 	u8 i;
1616 
1617 	/*
1618 	 * Retrieve device configuration from the device.
1619 	 * The array received contains all customization settings done at the
1620 	 * factory/manufacturer. Format of the array is documented at the
1621 	 * time of writing at:
1622 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1623 	 */
1624 	config_buf = kmalloc(config_size, GFP_KERNEL);
1625 	if (!config_buf)
1626 		return -ENOMEM;
1627 
1628 	result = cp210x_read_vendor_block(serial,
1629 					  REQTYPE_DEVICE_TO_HOST,
1630 					  CP210X_READ_2NCONFIG,
1631 					  config_buf,
1632 					  config_size);
1633 	if (result < 0) {
1634 		kfree(config_buf);
1635 		return result;
1636 	}
1637 
1638 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1639 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1640 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1641 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1642 
1643 	kfree(config_buf);
1644 
1645 	/* Make sure this is a config format we understand. */
1646 	if (config_version != 0x01)
1647 		return -ENOTSUPP;
1648 
1649 	priv->gc.ngpio = 4;
1650 
1651 	/*
1652 	 * Get default pin states after reset. Needed so we can determine
1653 	 * the direction of an open-drain pin.
1654 	 */
1655 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1656 
1657 	/* 0 indicates open-drain mode, 1 is push-pull */
1658 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1659 
1660 	/* 0 indicates GPIO mode, 1 is alternate function */
1661 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1662 
1663 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1664 		/*
1665 		 * For the QFN28 package, GPIO4-6 are controlled by
1666 		 * the low three bits of the mode/latch fields.
1667 		 * Contrary to the document linked above, the bits for
1668 		 * the SUSPEND pins are elsewhere.  No alternate
1669 		 * function is available for these pins.
1670 		 */
1671 		priv->gc.ngpio = 7;
1672 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1673 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1674 	}
1675 
1676 	/*
1677 	 * The CP2102N does not strictly has input and output pin modes,
1678 	 * it only knows open-drain and push-pull modes which is set at
1679 	 * factory. An open-drain pin can function both as an
1680 	 * input or an output. We emulate input mode for open-drain pins
1681 	 * by making sure they are not driven low, and we do not allow
1682 	 * push-pull pins to be set as an input.
1683 	 */
1684 	for (i = 0; i < priv->gc.ngpio; ++i) {
1685 		/*
1686 		 * Set direction to "input" iff pin is open-drain and reset
1687 		 * value is 1.
1688 		 */
1689 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1690 			priv->gpio_input |= BIT(i);
1691 	}
1692 
1693 	return 0;
1694 }
1695 
1696 static int cp210x_gpio_init(struct usb_serial *serial)
1697 {
1698 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1699 	int result;
1700 
1701 	switch (priv->partnum) {
1702 	case CP210X_PARTNUM_CP2104:
1703 		result = cp2104_gpioconf_init(serial);
1704 		break;
1705 	case CP210X_PARTNUM_CP2105:
1706 		result = cp2105_gpioconf_init(serial);
1707 		break;
1708 	case CP210X_PARTNUM_CP2102N_QFN28:
1709 	case CP210X_PARTNUM_CP2102N_QFN24:
1710 	case CP210X_PARTNUM_CP2102N_QFN20:
1711 		result = cp2102n_gpioconf_init(serial);
1712 		break;
1713 	default:
1714 		return 0;
1715 	}
1716 
1717 	if (result < 0)
1718 		return result;
1719 
1720 	priv->gc.label = "cp210x";
1721 	priv->gc.request = cp210x_gpio_request;
1722 	priv->gc.get_direction = cp210x_gpio_direction_get;
1723 	priv->gc.direction_input = cp210x_gpio_direction_input;
1724 	priv->gc.direction_output = cp210x_gpio_direction_output;
1725 	priv->gc.get = cp210x_gpio_get;
1726 	priv->gc.set = cp210x_gpio_set;
1727 	priv->gc.set_config = cp210x_gpio_set_config;
1728 	priv->gc.owner = THIS_MODULE;
1729 	priv->gc.parent = &serial->interface->dev;
1730 	priv->gc.base = -1;
1731 	priv->gc.can_sleep = true;
1732 
1733 	result = gpiochip_add_data(&priv->gc, serial);
1734 	if (!result)
1735 		priv->gpio_registered = true;
1736 
1737 	return result;
1738 }
1739 
1740 static void cp210x_gpio_remove(struct usb_serial *serial)
1741 {
1742 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1743 
1744 	if (priv->gpio_registered) {
1745 		gpiochip_remove(&priv->gc);
1746 		priv->gpio_registered = false;
1747 	}
1748 }
1749 
1750 #else
1751 
1752 static int cp210x_gpio_init(struct usb_serial *serial)
1753 {
1754 	return 0;
1755 }
1756 
1757 static void cp210x_gpio_remove(struct usb_serial *serial)
1758 {
1759 	/* Nothing to do */
1760 }
1761 
1762 #endif
1763 
1764 static int cp210x_port_probe(struct usb_serial_port *port)
1765 {
1766 	struct usb_serial *serial = port->serial;
1767 	struct cp210x_port_private *port_priv;
1768 
1769 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1770 	if (!port_priv)
1771 		return -ENOMEM;
1772 
1773 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1774 
1775 	usb_set_serial_port_data(port, port_priv);
1776 
1777 	return 0;
1778 }
1779 
1780 static int cp210x_port_remove(struct usb_serial_port *port)
1781 {
1782 	struct cp210x_port_private *port_priv;
1783 
1784 	port_priv = usb_get_serial_port_data(port);
1785 	kfree(port_priv);
1786 
1787 	return 0;
1788 }
1789 
1790 static void cp210x_init_max_speed(struct usb_serial *serial)
1791 {
1792 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1793 	bool use_actual_rate = false;
1794 	speed_t min = 300;
1795 	speed_t max;
1796 
1797 	switch (priv->partnum) {
1798 	case CP210X_PARTNUM_CP2101:
1799 		max = 921600;
1800 		break;
1801 	case CP210X_PARTNUM_CP2102:
1802 	case CP210X_PARTNUM_CP2103:
1803 		max = 1000000;
1804 		break;
1805 	case CP210X_PARTNUM_CP2104:
1806 		use_actual_rate = true;
1807 		max = 2000000;
1808 		break;
1809 	case CP210X_PARTNUM_CP2108:
1810 		max = 2000000;
1811 		break;
1812 	case CP210X_PARTNUM_CP2105:
1813 		if (cp210x_interface_num(serial) == 0) {
1814 			use_actual_rate = true;
1815 			max = 2000000;	/* ECI */
1816 		} else {
1817 			min = 2400;
1818 			max = 921600;	/* SCI */
1819 		}
1820 		break;
1821 	case CP210X_PARTNUM_CP2102N_QFN28:
1822 	case CP210X_PARTNUM_CP2102N_QFN24:
1823 	case CP210X_PARTNUM_CP2102N_QFN20:
1824 		use_actual_rate = true;
1825 		max = 3000000;
1826 		break;
1827 	default:
1828 		max = 2000000;
1829 		break;
1830 	}
1831 
1832 	priv->min_speed = min;
1833 	priv->max_speed = max;
1834 	priv->use_actual_rate = use_actual_rate;
1835 }
1836 
1837 static int cp210x_attach(struct usb_serial *serial)
1838 {
1839 	int result;
1840 	struct cp210x_serial_private *priv;
1841 
1842 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1843 	if (!priv)
1844 		return -ENOMEM;
1845 
1846 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1847 					  CP210X_GET_PARTNUM, &priv->partnum,
1848 					  sizeof(priv->partnum));
1849 	if (result < 0) {
1850 		dev_warn(&serial->interface->dev,
1851 			 "querying part number failed\n");
1852 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1853 	}
1854 
1855 	usb_set_serial_data(serial, priv);
1856 
1857 	cp210x_init_max_speed(serial);
1858 
1859 	result = cp210x_gpio_init(serial);
1860 	if (result < 0) {
1861 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1862 				result);
1863 	}
1864 
1865 	return 0;
1866 }
1867 
1868 static void cp210x_disconnect(struct usb_serial *serial)
1869 {
1870 	cp210x_gpio_remove(serial);
1871 }
1872 
1873 static void cp210x_release(struct usb_serial *serial)
1874 {
1875 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1876 
1877 	cp210x_gpio_remove(serial);
1878 
1879 	kfree(priv);
1880 }
1881 
1882 module_usb_serial_driver(serial_drivers, id_table);
1883 
1884 MODULE_DESCRIPTION(DRIVER_DESC);
1885 MODULE_LICENSE("GPL v2");
1886