xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 3a35093a)
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(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
206 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
207 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
208 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
209 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
210 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
211 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
212 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
213 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
214 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
215 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
216 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
217 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
218 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
219 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
220 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
221 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
222 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
223 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
227 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
228 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
229 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
230 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
231 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
232 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
233 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
234 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
235 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
236 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
237 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
238 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
239 	{ } /* Terminating Entry */
240 };
241 
242 MODULE_DEVICE_TABLE(usb, id_table);
243 
244 struct cp210x_serial_private {
245 #ifdef CONFIG_GPIOLIB
246 	struct gpio_chip	gc;
247 	bool			gpio_registered;
248 	u8			gpio_pushpull;
249 	u8			gpio_altfunc;
250 	u8			gpio_input;
251 #endif
252 	u8			partnum;
253 	speed_t			min_speed;
254 	speed_t			max_speed;
255 	bool			use_actual_rate;
256 };
257 
258 enum cp210x_event_state {
259 	ES_DATA,
260 	ES_ESCAPE,
261 	ES_LSR,
262 	ES_LSR_DATA_0,
263 	ES_LSR_DATA_1,
264 	ES_MSR
265 };
266 
267 struct cp210x_port_private {
268 	u8			bInterfaceNumber;
269 	bool			event_mode;
270 	enum cp210x_event_state event_state;
271 	u8 lsr;
272 };
273 
274 static struct usb_serial_driver cp210x_device = {
275 	.driver = {
276 		.owner =	THIS_MODULE,
277 		.name =		"cp210x",
278 	},
279 	.id_table		= id_table,
280 	.num_ports		= 1,
281 	.bulk_in_size		= 256,
282 	.bulk_out_size		= 256,
283 	.open			= cp210x_open,
284 	.close			= cp210x_close,
285 	.break_ctl		= cp210x_break_ctl,
286 	.set_termios		= cp210x_set_termios,
287 	.tx_empty		= cp210x_tx_empty,
288 	.throttle		= usb_serial_generic_throttle,
289 	.unthrottle		= usb_serial_generic_unthrottle,
290 	.tiocmget		= cp210x_tiocmget,
291 	.tiocmset		= cp210x_tiocmset,
292 	.get_icount		= usb_serial_generic_get_icount,
293 	.attach			= cp210x_attach,
294 	.disconnect		= cp210x_disconnect,
295 	.release		= cp210x_release,
296 	.port_probe		= cp210x_port_probe,
297 	.port_remove		= cp210x_port_remove,
298 	.dtr_rts		= cp210x_dtr_rts,
299 	.process_read_urb	= cp210x_process_read_urb,
300 };
301 
302 static struct usb_serial_driver * const serial_drivers[] = {
303 	&cp210x_device, NULL
304 };
305 
306 /* Config request types */
307 #define REQTYPE_HOST_TO_INTERFACE	0x41
308 #define REQTYPE_INTERFACE_TO_HOST	0xc1
309 #define REQTYPE_HOST_TO_DEVICE	0x40
310 #define REQTYPE_DEVICE_TO_HOST	0xc0
311 
312 /* Config request codes */
313 #define CP210X_IFC_ENABLE	0x00
314 #define CP210X_SET_BAUDDIV	0x01
315 #define CP210X_GET_BAUDDIV	0x02
316 #define CP210X_SET_LINE_CTL	0x03
317 #define CP210X_GET_LINE_CTL	0x04
318 #define CP210X_SET_BREAK	0x05
319 #define CP210X_IMM_CHAR		0x06
320 #define CP210X_SET_MHS		0x07
321 #define CP210X_GET_MDMSTS	0x08
322 #define CP210X_SET_XON		0x09
323 #define CP210X_SET_XOFF		0x0A
324 #define CP210X_SET_EVENTMASK	0x0B
325 #define CP210X_GET_EVENTMASK	0x0C
326 #define CP210X_SET_CHAR		0x0D
327 #define CP210X_GET_CHARS	0x0E
328 #define CP210X_GET_PROPS	0x0F
329 #define CP210X_GET_COMM_STATUS	0x10
330 #define CP210X_RESET		0x11
331 #define CP210X_PURGE		0x12
332 #define CP210X_SET_FLOW		0x13
333 #define CP210X_GET_FLOW		0x14
334 #define CP210X_EMBED_EVENTS	0x15
335 #define CP210X_GET_EVENTSTATE	0x16
336 #define CP210X_SET_CHARS	0x19
337 #define CP210X_GET_BAUDRATE	0x1D
338 #define CP210X_SET_BAUDRATE	0x1E
339 #define CP210X_VENDOR_SPECIFIC	0xFF
340 
341 /* CP210X_IFC_ENABLE */
342 #define UART_ENABLE		0x0001
343 #define UART_DISABLE		0x0000
344 
345 /* CP210X_(SET|GET)_BAUDDIV */
346 #define BAUD_RATE_GEN_FREQ	0x384000
347 
348 /* CP210X_(SET|GET)_LINE_CTL */
349 #define BITS_DATA_MASK		0X0f00
350 #define BITS_DATA_5		0X0500
351 #define BITS_DATA_6		0X0600
352 #define BITS_DATA_7		0X0700
353 #define BITS_DATA_8		0X0800
354 #define BITS_DATA_9		0X0900
355 
356 #define BITS_PARITY_MASK	0x00f0
357 #define BITS_PARITY_NONE	0x0000
358 #define BITS_PARITY_ODD		0x0010
359 #define BITS_PARITY_EVEN	0x0020
360 #define BITS_PARITY_MARK	0x0030
361 #define BITS_PARITY_SPACE	0x0040
362 
363 #define BITS_STOP_MASK		0x000f
364 #define BITS_STOP_1		0x0000
365 #define BITS_STOP_1_5		0x0001
366 #define BITS_STOP_2		0x0002
367 
368 /* CP210X_SET_BREAK */
369 #define BREAK_ON		0x0001
370 #define BREAK_OFF		0x0000
371 
372 /* CP210X_(SET_MHS|GET_MDMSTS) */
373 #define CONTROL_DTR		0x0001
374 #define CONTROL_RTS		0x0002
375 #define CONTROL_CTS		0x0010
376 #define CONTROL_DSR		0x0020
377 #define CONTROL_RING		0x0040
378 #define CONTROL_DCD		0x0080
379 #define CONTROL_WRITE_DTR	0x0100
380 #define CONTROL_WRITE_RTS	0x0200
381 
382 /* CP210X_VENDOR_SPECIFIC values */
383 #define CP210X_READ_2NCONFIG	0x000E
384 #define CP210X_READ_LATCH	0x00C2
385 #define CP210X_GET_PARTNUM	0x370B
386 #define CP210X_GET_PORTCONFIG	0x370C
387 #define CP210X_GET_DEVICEMODE	0x3711
388 #define CP210X_WRITE_LATCH	0x37E1
389 
390 /* Part number definitions */
391 #define CP210X_PARTNUM_CP2101	0x01
392 #define CP210X_PARTNUM_CP2102	0x02
393 #define CP210X_PARTNUM_CP2103	0x03
394 #define CP210X_PARTNUM_CP2104	0x04
395 #define CP210X_PARTNUM_CP2105	0x05
396 #define CP210X_PARTNUM_CP2108	0x08
397 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
398 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
399 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
400 #define CP210X_PARTNUM_UNKNOWN	0xFF
401 
402 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
403 struct cp210x_comm_status {
404 	__le32   ulErrors;
405 	__le32   ulHoldReasons;
406 	__le32   ulAmountInInQueue;
407 	__le32   ulAmountInOutQueue;
408 	u8       bEofReceived;
409 	u8       bWaitForImmediate;
410 	u8       bReserved;
411 } __packed;
412 
413 /*
414  * CP210X_PURGE - 16 bits passed in wValue of USB request.
415  * SiLabs app note AN571 gives a strange description of the 4 bits:
416  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
417  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
418  */
419 #define PURGE_ALL		0x000f
420 
421 /* CP210X_EMBED_EVENTS */
422 #define CP210X_ESCCHAR		0xec
423 
424 #define CP210X_LSR_OVERRUN	BIT(1)
425 #define CP210X_LSR_PARITY	BIT(2)
426 #define CP210X_LSR_FRAME	BIT(3)
427 #define CP210X_LSR_BREAK	BIT(4)
428 
429 
430 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
431 struct cp210x_flow_ctl {
432 	__le32	ulControlHandshake;
433 	__le32	ulFlowReplace;
434 	__le32	ulXonLimit;
435 	__le32	ulXoffLimit;
436 };
437 
438 /* cp210x_flow_ctl::ulControlHandshake */
439 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
440 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
441 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
442 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
443 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
444 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
445 
446 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
447 #define CP210X_SERIAL_DTR_INACTIVE	0
448 #define CP210X_SERIAL_DTR_ACTIVE	1
449 #define CP210X_SERIAL_DTR_FLOW_CTL	2
450 
451 /* cp210x_flow_ctl::ulFlowReplace */
452 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
453 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
454 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
455 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
456 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
457 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
458 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
459 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
460 
461 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
462 #define CP210X_SERIAL_RTS_INACTIVE	0
463 #define CP210X_SERIAL_RTS_ACTIVE	1
464 #define CP210X_SERIAL_RTS_FLOW_CTL	2
465 
466 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
467 struct cp210x_pin_mode {
468 	u8	eci;
469 	u8	sci;
470 };
471 
472 #define CP210X_PIN_MODE_MODEM		0
473 #define CP210X_PIN_MODE_GPIO		BIT(0)
474 
475 /*
476  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
477  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
478  */
479 struct cp210x_dual_port_config {
480 	__le16	gpio_mode;
481 	u8	__pad0[2];
482 	__le16	reset_state;
483 	u8	__pad1[4];
484 	__le16	suspend_state;
485 	u8	sci_cfg;
486 	u8	eci_cfg;
487 	u8	device_cfg;
488 } __packed;
489 
490 /*
491  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
492  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
493  */
494 struct cp210x_single_port_config {
495 	__le16	gpio_mode;
496 	u8	__pad0[2];
497 	__le16	reset_state;
498 	u8	__pad1[4];
499 	__le16	suspend_state;
500 	u8	device_cfg;
501 } __packed;
502 
503 /* GPIO modes */
504 #define CP210X_SCI_GPIO_MODE_OFFSET	9
505 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
506 
507 #define CP210X_ECI_GPIO_MODE_OFFSET	2
508 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
509 
510 #define CP210X_GPIO_MODE_OFFSET		8
511 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
512 
513 /* CP2105 port configuration values */
514 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
515 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
516 #define CP2105_GPIO1_RS485_MODE		BIT(2)
517 
518 /* CP2104 port configuration values */
519 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
520 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
521 #define CP2104_GPIO2_RS485_MODE		BIT(2)
522 
523 /* CP2102N configuration array indices */
524 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
525 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
526 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
527 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
528 
529 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
530 struct cp210x_gpio_write {
531 	u8	mask;
532 	u8	state;
533 };
534 
535 /*
536  * Helper to get interface number when we only have struct usb_serial.
537  */
538 static u8 cp210x_interface_num(struct usb_serial *serial)
539 {
540 	struct usb_host_interface *cur_altsetting;
541 
542 	cur_altsetting = serial->interface->cur_altsetting;
543 
544 	return cur_altsetting->desc.bInterfaceNumber;
545 }
546 
547 /*
548  * Reads a variable-sized block of CP210X_ registers, identified by req.
549  * Returns data into buf in native USB byte order.
550  */
551 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
552 		void *buf, int bufsize)
553 {
554 	struct usb_serial *serial = port->serial;
555 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
556 	void *dmabuf;
557 	int result;
558 
559 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
560 	if (!dmabuf)
561 		return -ENOMEM;
562 
563 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
564 			req, REQTYPE_INTERFACE_TO_HOST, 0,
565 			port_priv->bInterfaceNumber, dmabuf, bufsize,
566 			USB_CTRL_SET_TIMEOUT);
567 	if (result == bufsize) {
568 		memcpy(buf, dmabuf, bufsize);
569 		result = 0;
570 	} else {
571 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
572 				req, bufsize, result);
573 		if (result >= 0)
574 			result = -EIO;
575 	}
576 
577 	kfree(dmabuf);
578 
579 	return result;
580 }
581 
582 /*
583  * Reads any 8-bit CP210X_ register identified by req.
584  */
585 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
586 {
587 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
588 }
589 
590 /*
591  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
592  * Returns data into buf in native USB byte order.
593  */
594 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
595 				    void *buf, int bufsize)
596 {
597 	void *dmabuf;
598 	int result;
599 
600 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
601 	if (!dmabuf)
602 		return -ENOMEM;
603 
604 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
605 				 CP210X_VENDOR_SPECIFIC, type, val,
606 				 cp210x_interface_num(serial), dmabuf, bufsize,
607 				 USB_CTRL_GET_TIMEOUT);
608 	if (result == bufsize) {
609 		memcpy(buf, dmabuf, bufsize);
610 		result = 0;
611 	} else {
612 		dev_err(&serial->interface->dev,
613 			"failed to get vendor val 0x%04x size %d: %d\n", val,
614 			bufsize, result);
615 		if (result >= 0)
616 			result = -EIO;
617 	}
618 
619 	kfree(dmabuf);
620 
621 	return result;
622 }
623 
624 /*
625  * Writes any 16-bit CP210X_ register (req) whose value is passed
626  * entirely in the wValue field of the USB request.
627  */
628 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
629 {
630 	struct usb_serial *serial = port->serial;
631 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
632 	int result;
633 
634 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
635 			req, REQTYPE_HOST_TO_INTERFACE, val,
636 			port_priv->bInterfaceNumber, NULL, 0,
637 			USB_CTRL_SET_TIMEOUT);
638 	if (result < 0) {
639 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
640 				req, result);
641 	}
642 
643 	return result;
644 }
645 
646 /*
647  * Writes a variable-sized block of CP210X_ registers, identified by req.
648  * Data in buf must be in native USB byte order.
649  */
650 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
651 		void *buf, int bufsize)
652 {
653 	struct usb_serial *serial = port->serial;
654 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
655 	void *dmabuf;
656 	int result;
657 
658 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
659 	if (!dmabuf)
660 		return -ENOMEM;
661 
662 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
663 			req, REQTYPE_HOST_TO_INTERFACE, 0,
664 			port_priv->bInterfaceNumber, dmabuf, bufsize,
665 			USB_CTRL_SET_TIMEOUT);
666 
667 	kfree(dmabuf);
668 
669 	if (result == bufsize) {
670 		result = 0;
671 	} else {
672 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
673 				req, bufsize, result);
674 		if (result >= 0)
675 			result = -EIO;
676 	}
677 
678 	return result;
679 }
680 
681 /*
682  * Writes any 32-bit CP210X_ register identified by req.
683  */
684 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
685 {
686 	__le32 le32_val;
687 
688 	le32_val = cpu_to_le32(val);
689 
690 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
691 }
692 
693 #ifdef CONFIG_GPIOLIB
694 /*
695  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
696  * Data in buf must be in native USB byte order.
697  */
698 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
699 				     u16 val, void *buf, int bufsize)
700 {
701 	void *dmabuf;
702 	int result;
703 
704 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
705 	if (!dmabuf)
706 		return -ENOMEM;
707 
708 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
709 				 CP210X_VENDOR_SPECIFIC, type, val,
710 				 cp210x_interface_num(serial), dmabuf, bufsize,
711 				 USB_CTRL_SET_TIMEOUT);
712 
713 	kfree(dmabuf);
714 
715 	if (result == bufsize) {
716 		result = 0;
717 	} else {
718 		dev_err(&serial->interface->dev,
719 			"failed to set vendor val 0x%04x size %d: %d\n", val,
720 			bufsize, result);
721 		if (result >= 0)
722 			result = -EIO;
723 	}
724 
725 	return result;
726 }
727 #endif
728 
729 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
730 {
731 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
732 	int result;
733 
734 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
735 	if (result) {
736 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
737 		return result;
738 	}
739 
740 	if (tty)
741 		cp210x_set_termios(tty, port, NULL);
742 
743 	result = usb_serial_generic_open(tty, port);
744 	if (result)
745 		goto err_disable;
746 
747 	return 0;
748 
749 err_disable:
750 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
751 	port_priv->event_mode = false;
752 
753 	return result;
754 }
755 
756 static void cp210x_close(struct usb_serial_port *port)
757 {
758 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
759 
760 	usb_serial_generic_close(port);
761 
762 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
763 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
764 
765 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
766 
767 	/* Disabling the interface disables event-insertion mode. */
768 	port_priv->event_mode = false;
769 }
770 
771 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
772 {
773 	if (lsr & CP210X_LSR_BREAK) {
774 		port->icount.brk++;
775 		*flag = TTY_BREAK;
776 	} else if (lsr & CP210X_LSR_PARITY) {
777 		port->icount.parity++;
778 		*flag = TTY_PARITY;
779 	} else if (lsr & CP210X_LSR_FRAME) {
780 		port->icount.frame++;
781 		*flag = TTY_FRAME;
782 	}
783 
784 	if (lsr & CP210X_LSR_OVERRUN) {
785 		port->icount.overrun++;
786 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
787 	}
788 }
789 
790 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
791 {
792 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
793 
794 	switch (port_priv->event_state) {
795 	case ES_DATA:
796 		if (*ch == CP210X_ESCCHAR) {
797 			port_priv->event_state = ES_ESCAPE;
798 			break;
799 		}
800 		return false;
801 	case ES_ESCAPE:
802 		switch (*ch) {
803 		case 0:
804 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
805 			*ch = CP210X_ESCCHAR;
806 			port_priv->event_state = ES_DATA;
807 			return false;
808 		case 1:
809 			port_priv->event_state = ES_LSR_DATA_0;
810 			break;
811 		case 2:
812 			port_priv->event_state = ES_LSR;
813 			break;
814 		case 3:
815 			port_priv->event_state = ES_MSR;
816 			break;
817 		default:
818 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
819 			port_priv->event_state = ES_DATA;
820 			break;
821 		}
822 		break;
823 	case ES_LSR_DATA_0:
824 		port_priv->lsr = *ch;
825 		port_priv->event_state = ES_LSR_DATA_1;
826 		break;
827 	case ES_LSR_DATA_1:
828 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
829 				__func__, port_priv->lsr, *ch);
830 		cp210x_process_lsr(port, port_priv->lsr, flag);
831 		port_priv->event_state = ES_DATA;
832 		return false;
833 	case ES_LSR:
834 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
835 		port_priv->lsr = *ch;
836 		cp210x_process_lsr(port, port_priv->lsr, flag);
837 		port_priv->event_state = ES_DATA;
838 		break;
839 	case ES_MSR:
840 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
841 		/* unimplemented */
842 		port_priv->event_state = ES_DATA;
843 		break;
844 	}
845 
846 	return true;
847 }
848 
849 static void cp210x_process_read_urb(struct urb *urb)
850 {
851 	struct usb_serial_port *port = urb->context;
852 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
853 	unsigned char *ch = urb->transfer_buffer;
854 	char flag;
855 	int i;
856 
857 	if (!urb->actual_length)
858 		return;
859 
860 	if (port_priv->event_mode) {
861 		for (i = 0; i < urb->actual_length; i++, ch++) {
862 			flag = TTY_NORMAL;
863 
864 			if (cp210x_process_char(port, ch, &flag))
865 				continue;
866 
867 			tty_insert_flip_char(&port->port, *ch, flag);
868 		}
869 	} else {
870 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
871 	}
872 	tty_flip_buffer_push(&port->port);
873 }
874 
875 /*
876  * Read how many bytes are waiting in the TX queue.
877  */
878 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
879 		u32 *count)
880 {
881 	struct usb_serial *serial = port->serial;
882 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
883 	struct cp210x_comm_status *sts;
884 	int result;
885 
886 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
887 	if (!sts)
888 		return -ENOMEM;
889 
890 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
891 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
892 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
893 			USB_CTRL_GET_TIMEOUT);
894 	if (result == sizeof(*sts)) {
895 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
896 		result = 0;
897 	} else {
898 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
899 		if (result >= 0)
900 			result = -EIO;
901 	}
902 
903 	kfree(sts);
904 
905 	return result;
906 }
907 
908 static bool cp210x_tx_empty(struct usb_serial_port *port)
909 {
910 	int err;
911 	u32 count;
912 
913 	err = cp210x_get_tx_queue_byte_count(port, &count);
914 	if (err)
915 		return true;
916 
917 	return !count;
918 }
919 
920 struct cp210x_rate {
921 	speed_t rate;
922 	speed_t high;
923 };
924 
925 static const struct cp210x_rate cp210x_an205_table1[] = {
926 	{ 300, 300 },
927 	{ 600, 600 },
928 	{ 1200, 1200 },
929 	{ 1800, 1800 },
930 	{ 2400, 2400 },
931 	{ 4000, 4000 },
932 	{ 4800, 4803 },
933 	{ 7200, 7207 },
934 	{ 9600, 9612 },
935 	{ 14400, 14428 },
936 	{ 16000, 16062 },
937 	{ 19200, 19250 },
938 	{ 28800, 28912 },
939 	{ 38400, 38601 },
940 	{ 51200, 51558 },
941 	{ 56000, 56280 },
942 	{ 57600, 58053 },
943 	{ 64000, 64111 },
944 	{ 76800, 77608 },
945 	{ 115200, 117028 },
946 	{ 128000, 129347 },
947 	{ 153600, 156868 },
948 	{ 230400, 237832 },
949 	{ 250000, 254234 },
950 	{ 256000, 273066 },
951 	{ 460800, 491520 },
952 	{ 500000, 567138 },
953 	{ 576000, 670254 },
954 	{ 921600, UINT_MAX }
955 };
956 
957 /*
958  * Quantises the baud rate as per AN205 Table 1
959  */
960 static speed_t cp210x_get_an205_rate(speed_t baud)
961 {
962 	int i;
963 
964 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
965 		if (baud <= cp210x_an205_table1[i].high)
966 			break;
967 	}
968 
969 	return cp210x_an205_table1[i].rate;
970 }
971 
972 static speed_t cp210x_get_actual_rate(speed_t baud)
973 {
974 	unsigned int prescale = 1;
975 	unsigned int div;
976 
977 	if (baud <= 365)
978 		prescale = 4;
979 
980 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
981 	baud = 48000000 / (2 * prescale * div);
982 
983 	return baud;
984 }
985 
986 /*
987  * CP2101 supports the following baud rates:
988  *
989  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
990  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
991  *
992  * CP2102 and CP2103 support the following additional rates:
993  *
994  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
995  *	576000
996  *
997  * The device will map a requested rate to a supported one, but the result
998  * of requests for rates greater than 1053257 is undefined (see AN205).
999  *
1000  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1001  * respectively, with an error less than 1%. The actual rates are determined
1002  * by
1003  *
1004  *	div = round(freq / (2 x prescale x request))
1005  *	actual = freq / (2 x prescale x div)
1006  *
1007  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1008  * or 1 otherwise.
1009  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1010  * otherwise.
1011  */
1012 static void cp210x_change_speed(struct tty_struct *tty,
1013 		struct usb_serial_port *port, struct ktermios *old_termios)
1014 {
1015 	struct usb_serial *serial = port->serial;
1016 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1017 	u32 baud;
1018 
1019 	/*
1020 	 * This maps the requested rate to the actual rate, a valid rate on
1021 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1022 	 *
1023 	 * NOTE: B0 is not implemented.
1024 	 */
1025 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1026 
1027 	if (priv->use_actual_rate)
1028 		baud = cp210x_get_actual_rate(baud);
1029 	else if (baud < 1000000)
1030 		baud = cp210x_get_an205_rate(baud);
1031 
1032 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1033 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1034 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1035 		if (old_termios)
1036 			baud = old_termios->c_ospeed;
1037 		else
1038 			baud = 9600;
1039 	}
1040 
1041 	tty_encode_baud_rate(tty, baud, baud);
1042 }
1043 
1044 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1045 {
1046 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1047 	int ret;
1048 
1049 	if (port_priv->event_mode)
1050 		return;
1051 
1052 	port_priv->event_state = ES_DATA;
1053 	port_priv->event_mode = true;
1054 
1055 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1056 	if (ret) {
1057 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1058 		port_priv->event_mode = false;
1059 	}
1060 }
1061 
1062 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1063 {
1064 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1065 	int ret;
1066 
1067 	if (!port_priv->event_mode)
1068 		return;
1069 
1070 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1071 	if (ret) {
1072 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1073 		return;
1074 	}
1075 
1076 	port_priv->event_mode = false;
1077 }
1078 
1079 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1080 {
1081 	bool iflag_change;
1082 
1083 	iflag_change = ((a->c_iflag ^ b->c_iflag) & INPCK);
1084 
1085 	return tty_termios_hw_change(a, b) || iflag_change;
1086 }
1087 
1088 static void cp210x_set_flow_control(struct tty_struct *tty,
1089 		struct usb_serial_port *port, struct ktermios *old_termios)
1090 {
1091 	struct cp210x_flow_ctl flow_ctl;
1092 	u32 flow_repl;
1093 	u32 ctl_hs;
1094 	int ret;
1095 
1096 	if (old_termios && C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS))
1097 		return;
1098 
1099 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1100 			sizeof(flow_ctl));
1101 	if (ret)
1102 		return;
1103 
1104 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1105 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1106 
1107 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1108 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1109 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1110 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1111 	ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1112 
1113 	if (C_CRTSCTS(tty)) {
1114 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1115 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1116 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
1117 	} else {
1118 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1119 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1120 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_ACTIVE);
1121 	}
1122 
1123 	dev_dbg(&port->dev, "%s - ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1124 			__func__, ctl_hs, flow_repl);
1125 
1126 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1127 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1128 
1129 	cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1130 			sizeof(flow_ctl));
1131 }
1132 
1133 static void cp210x_set_termios(struct tty_struct *tty,
1134 		struct usb_serial_port *port, struct ktermios *old_termios)
1135 {
1136 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1137 	u16 bits;
1138 	int ret;
1139 
1140 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1141 		return;
1142 
1143 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1144 		cp210x_change_speed(tty, port, old_termios);
1145 
1146 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1147 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1148 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1149 		tty->termios.c_cflag |= CS8;
1150 	}
1151 
1152 	bits = 0;
1153 
1154 	switch (C_CSIZE(tty)) {
1155 	case CS5:
1156 		bits |= BITS_DATA_5;
1157 		break;
1158 	case CS6:
1159 		bits |= BITS_DATA_6;
1160 		break;
1161 	case CS7:
1162 		bits |= BITS_DATA_7;
1163 		break;
1164 	case CS8:
1165 	default:
1166 		bits |= BITS_DATA_8;
1167 		break;
1168 	}
1169 
1170 	if (C_PARENB(tty)) {
1171 		if (C_CMSPAR(tty)) {
1172 			if (C_PARODD(tty))
1173 				bits |= BITS_PARITY_MARK;
1174 			else
1175 				bits |= BITS_PARITY_SPACE;
1176 		} else {
1177 			if (C_PARODD(tty))
1178 				bits |= BITS_PARITY_ODD;
1179 			else
1180 				bits |= BITS_PARITY_EVEN;
1181 		}
1182 	}
1183 
1184 	if (C_CSTOPB(tty))
1185 		bits |= BITS_STOP_2;
1186 	else
1187 		bits |= BITS_STOP_1;
1188 
1189 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1190 	if (ret)
1191 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1192 
1193 	cp210x_set_flow_control(tty, port, old_termios);
1194 
1195 	/*
1196 	 * Enable event-insertion mode only if input parity checking is
1197 	 * enabled for now.
1198 	 */
1199 	if (I_INPCK(tty))
1200 		cp210x_enable_event_mode(port);
1201 	else
1202 		cp210x_disable_event_mode(port);
1203 }
1204 
1205 static int cp210x_tiocmset(struct tty_struct *tty,
1206 		unsigned int set, unsigned int clear)
1207 {
1208 	struct usb_serial_port *port = tty->driver_data;
1209 	return cp210x_tiocmset_port(port, set, clear);
1210 }
1211 
1212 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1213 		unsigned int set, unsigned int clear)
1214 {
1215 	u16 control = 0;
1216 
1217 	if (set & TIOCM_RTS) {
1218 		control |= CONTROL_RTS;
1219 		control |= CONTROL_WRITE_RTS;
1220 	}
1221 	if (set & TIOCM_DTR) {
1222 		control |= CONTROL_DTR;
1223 		control |= CONTROL_WRITE_DTR;
1224 	}
1225 	if (clear & TIOCM_RTS) {
1226 		control &= ~CONTROL_RTS;
1227 		control |= CONTROL_WRITE_RTS;
1228 	}
1229 	if (clear & TIOCM_DTR) {
1230 		control &= ~CONTROL_DTR;
1231 		control |= CONTROL_WRITE_DTR;
1232 	}
1233 
1234 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1235 
1236 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1237 }
1238 
1239 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1240 {
1241 	if (on)
1242 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1243 	else
1244 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1245 }
1246 
1247 static int cp210x_tiocmget(struct tty_struct *tty)
1248 {
1249 	struct usb_serial_port *port = tty->driver_data;
1250 	u8 control;
1251 	int result;
1252 
1253 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1254 	if (result)
1255 		return result;
1256 
1257 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1258 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1259 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1260 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1261 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1262 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1263 
1264 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1265 
1266 	return result;
1267 }
1268 
1269 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1270 {
1271 	struct usb_serial_port *port = tty->driver_data;
1272 	u16 state;
1273 
1274 	if (break_state == 0)
1275 		state = BREAK_OFF;
1276 	else
1277 		state = BREAK_ON;
1278 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1279 		state == BREAK_OFF ? "off" : "on");
1280 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1281 }
1282 
1283 #ifdef CONFIG_GPIOLIB
1284 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1285 {
1286 	struct usb_serial *serial = gpiochip_get_data(gc);
1287 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1288 
1289 	if (priv->gpio_altfunc & BIT(offset))
1290 		return -ENODEV;
1291 
1292 	return 0;
1293 }
1294 
1295 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1296 {
1297 	struct usb_serial *serial = gpiochip_get_data(gc);
1298 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1299 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1300 	int result;
1301 	u8 buf;
1302 
1303 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1304 		req_type = REQTYPE_INTERFACE_TO_HOST;
1305 
1306 	result = usb_autopm_get_interface(serial->interface);
1307 	if (result)
1308 		return result;
1309 
1310 	result = cp210x_read_vendor_block(serial, req_type,
1311 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1312 	usb_autopm_put_interface(serial->interface);
1313 	if (result < 0)
1314 		return result;
1315 
1316 	return !!(buf & BIT(gpio));
1317 }
1318 
1319 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1320 {
1321 	struct usb_serial *serial = gpiochip_get_data(gc);
1322 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1323 	struct cp210x_gpio_write buf;
1324 	int result;
1325 
1326 	if (value == 1)
1327 		buf.state = BIT(gpio);
1328 	else
1329 		buf.state = 0;
1330 
1331 	buf.mask = BIT(gpio);
1332 
1333 	result = usb_autopm_get_interface(serial->interface);
1334 	if (result)
1335 		goto out;
1336 
1337 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1338 		result = cp210x_write_vendor_block(serial,
1339 						   REQTYPE_HOST_TO_INTERFACE,
1340 						   CP210X_WRITE_LATCH, &buf,
1341 						   sizeof(buf));
1342 	} else {
1343 		u16 wIndex = buf.state << 8 | buf.mask;
1344 
1345 		result = usb_control_msg(serial->dev,
1346 					 usb_sndctrlpipe(serial->dev, 0),
1347 					 CP210X_VENDOR_SPECIFIC,
1348 					 REQTYPE_HOST_TO_DEVICE,
1349 					 CP210X_WRITE_LATCH,
1350 					 wIndex,
1351 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1352 	}
1353 
1354 	usb_autopm_put_interface(serial->interface);
1355 out:
1356 	if (result < 0) {
1357 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1358 				result);
1359 	}
1360 }
1361 
1362 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1363 {
1364 	struct usb_serial *serial = gpiochip_get_data(gc);
1365 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1366 
1367 	return priv->gpio_input & BIT(gpio);
1368 }
1369 
1370 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1371 {
1372 	struct usb_serial *serial = gpiochip_get_data(gc);
1373 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1374 
1375 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1376 		/* hardware does not support an input mode */
1377 		return -ENOTSUPP;
1378 	}
1379 
1380 	/* push-pull pins cannot be changed to be inputs */
1381 	if (priv->gpio_pushpull & BIT(gpio))
1382 		return -EINVAL;
1383 
1384 	/* make sure to release pin if it is being driven low */
1385 	cp210x_gpio_set(gc, gpio, 1);
1386 
1387 	priv->gpio_input |= BIT(gpio);
1388 
1389 	return 0;
1390 }
1391 
1392 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1393 					int value)
1394 {
1395 	struct usb_serial *serial = gpiochip_get_data(gc);
1396 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1397 
1398 	priv->gpio_input &= ~BIT(gpio);
1399 	cp210x_gpio_set(gc, gpio, value);
1400 
1401 	return 0;
1402 }
1403 
1404 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1405 				  unsigned long config)
1406 {
1407 	struct usb_serial *serial = gpiochip_get_data(gc);
1408 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1409 	enum pin_config_param param = pinconf_to_config_param(config);
1410 
1411 	/* Succeed only if in correct mode (this can't be set at runtime) */
1412 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1413 	    (priv->gpio_pushpull & BIT(gpio)))
1414 		return 0;
1415 
1416 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1417 	    !(priv->gpio_pushpull & BIT(gpio)))
1418 		return 0;
1419 
1420 	return -ENOTSUPP;
1421 }
1422 
1423 /*
1424  * This function is for configuring GPIO using shared pins, where other signals
1425  * are made unavailable by configuring the use of GPIO. This is believed to be
1426  * only applicable to the cp2105 at this point, the other devices supported by
1427  * this driver that provide GPIO do so in a way that does not impact other
1428  * signals and are thus expected to have very different initialisation.
1429  */
1430 static int cp2105_gpioconf_init(struct usb_serial *serial)
1431 {
1432 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1433 	struct cp210x_pin_mode mode;
1434 	struct cp210x_dual_port_config config;
1435 	u8 intf_num = cp210x_interface_num(serial);
1436 	u8 iface_config;
1437 	int result;
1438 
1439 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1440 					  CP210X_GET_DEVICEMODE, &mode,
1441 					  sizeof(mode));
1442 	if (result < 0)
1443 		return result;
1444 
1445 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1446 					  CP210X_GET_PORTCONFIG, &config,
1447 					  sizeof(config));
1448 	if (result < 0)
1449 		return result;
1450 
1451 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1452 	if (intf_num == 0) {
1453 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1454 			/* mark all GPIOs of this interface as reserved */
1455 			priv->gpio_altfunc = 0xff;
1456 			return 0;
1457 		}
1458 
1459 		iface_config = config.eci_cfg;
1460 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1461 						CP210X_ECI_GPIO_MODE_MASK) >>
1462 						CP210X_ECI_GPIO_MODE_OFFSET);
1463 		priv->gc.ngpio = 2;
1464 	} else if (intf_num == 1) {
1465 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1466 			/* mark all GPIOs of this interface as reserved */
1467 			priv->gpio_altfunc = 0xff;
1468 			return 0;
1469 		}
1470 
1471 		iface_config = config.sci_cfg;
1472 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1473 						CP210X_SCI_GPIO_MODE_MASK) >>
1474 						CP210X_SCI_GPIO_MODE_OFFSET);
1475 		priv->gc.ngpio = 3;
1476 	} else {
1477 		return -ENODEV;
1478 	}
1479 
1480 	/* mark all pins which are not in GPIO mode */
1481 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1482 		priv->gpio_altfunc |= BIT(0);
1483 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1484 			CP2105_GPIO1_RS485_MODE))
1485 		priv->gpio_altfunc |= BIT(1);
1486 
1487 	/* driver implementation for CP2105 only supports outputs */
1488 	priv->gpio_input = 0;
1489 
1490 	return 0;
1491 }
1492 
1493 static int cp2104_gpioconf_init(struct usb_serial *serial)
1494 {
1495 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1496 	struct cp210x_single_port_config config;
1497 	u8 iface_config;
1498 	u8 gpio_latch;
1499 	int result;
1500 	u8 i;
1501 
1502 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1503 					  CP210X_GET_PORTCONFIG, &config,
1504 					  sizeof(config));
1505 	if (result < 0)
1506 		return result;
1507 
1508 	priv->gc.ngpio = 4;
1509 
1510 	iface_config = config.device_cfg;
1511 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1512 					CP210X_GPIO_MODE_MASK) >>
1513 					CP210X_GPIO_MODE_OFFSET);
1514 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1515 					CP210X_GPIO_MODE_MASK) >>
1516 					CP210X_GPIO_MODE_OFFSET);
1517 
1518 	/* mark all pins which are not in GPIO mode */
1519 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1520 		priv->gpio_altfunc |= BIT(0);
1521 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1522 		priv->gpio_altfunc |= BIT(1);
1523 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1524 		priv->gpio_altfunc |= BIT(2);
1525 
1526 	/*
1527 	 * Like CP2102N, CP2104 has also no strict input and output pin
1528 	 * modes.
1529 	 * Do the same input mode emulation as CP2102N.
1530 	 */
1531 	for (i = 0; i < priv->gc.ngpio; ++i) {
1532 		/*
1533 		 * Set direction to "input" iff pin is open-drain and reset
1534 		 * value is 1.
1535 		 */
1536 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1537 			priv->gpio_input |= BIT(i);
1538 	}
1539 
1540 	return 0;
1541 }
1542 
1543 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1544 {
1545 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1546 	const u16 config_size = 0x02a6;
1547 	u8 gpio_rst_latch;
1548 	u8 config_version;
1549 	u8 gpio_pushpull;
1550 	u8 *config_buf;
1551 	u8 gpio_latch;
1552 	u8 gpio_ctrl;
1553 	int result;
1554 	u8 i;
1555 
1556 	/*
1557 	 * Retrieve device configuration from the device.
1558 	 * The array received contains all customization settings done at the
1559 	 * factory/manufacturer. Format of the array is documented at the
1560 	 * time of writing at:
1561 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1562 	 */
1563 	config_buf = kmalloc(config_size, GFP_KERNEL);
1564 	if (!config_buf)
1565 		return -ENOMEM;
1566 
1567 	result = cp210x_read_vendor_block(serial,
1568 					  REQTYPE_DEVICE_TO_HOST,
1569 					  CP210X_READ_2NCONFIG,
1570 					  config_buf,
1571 					  config_size);
1572 	if (result < 0) {
1573 		kfree(config_buf);
1574 		return result;
1575 	}
1576 
1577 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1578 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1579 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1580 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1581 
1582 	kfree(config_buf);
1583 
1584 	/* Make sure this is a config format we understand. */
1585 	if (config_version != 0x01)
1586 		return -ENOTSUPP;
1587 
1588 	priv->gc.ngpio = 4;
1589 
1590 	/*
1591 	 * Get default pin states after reset. Needed so we can determine
1592 	 * the direction of an open-drain pin.
1593 	 */
1594 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1595 
1596 	/* 0 indicates open-drain mode, 1 is push-pull */
1597 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1598 
1599 	/* 0 indicates GPIO mode, 1 is alternate function */
1600 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1601 
1602 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1603 		/*
1604 		 * For the QFN28 package, GPIO4-6 are controlled by
1605 		 * the low three bits of the mode/latch fields.
1606 		 * Contrary to the document linked above, the bits for
1607 		 * the SUSPEND pins are elsewhere.  No alternate
1608 		 * function is available for these pins.
1609 		 */
1610 		priv->gc.ngpio = 7;
1611 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1612 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1613 	}
1614 
1615 	/*
1616 	 * The CP2102N does not strictly has input and output pin modes,
1617 	 * it only knows open-drain and push-pull modes which is set at
1618 	 * factory. An open-drain pin can function both as an
1619 	 * input or an output. We emulate input mode for open-drain pins
1620 	 * by making sure they are not driven low, and we do not allow
1621 	 * push-pull pins to be set as an input.
1622 	 */
1623 	for (i = 0; i < priv->gc.ngpio; ++i) {
1624 		/*
1625 		 * Set direction to "input" iff pin is open-drain and reset
1626 		 * value is 1.
1627 		 */
1628 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1629 			priv->gpio_input |= BIT(i);
1630 	}
1631 
1632 	return 0;
1633 }
1634 
1635 static int cp210x_gpio_init(struct usb_serial *serial)
1636 {
1637 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1638 	int result;
1639 
1640 	switch (priv->partnum) {
1641 	case CP210X_PARTNUM_CP2104:
1642 		result = cp2104_gpioconf_init(serial);
1643 		break;
1644 	case CP210X_PARTNUM_CP2105:
1645 		result = cp2105_gpioconf_init(serial);
1646 		break;
1647 	case CP210X_PARTNUM_CP2102N_QFN28:
1648 	case CP210X_PARTNUM_CP2102N_QFN24:
1649 	case CP210X_PARTNUM_CP2102N_QFN20:
1650 		result = cp2102n_gpioconf_init(serial);
1651 		break;
1652 	default:
1653 		return 0;
1654 	}
1655 
1656 	if (result < 0)
1657 		return result;
1658 
1659 	priv->gc.label = "cp210x";
1660 	priv->gc.request = cp210x_gpio_request;
1661 	priv->gc.get_direction = cp210x_gpio_direction_get;
1662 	priv->gc.direction_input = cp210x_gpio_direction_input;
1663 	priv->gc.direction_output = cp210x_gpio_direction_output;
1664 	priv->gc.get = cp210x_gpio_get;
1665 	priv->gc.set = cp210x_gpio_set;
1666 	priv->gc.set_config = cp210x_gpio_set_config;
1667 	priv->gc.owner = THIS_MODULE;
1668 	priv->gc.parent = &serial->interface->dev;
1669 	priv->gc.base = -1;
1670 	priv->gc.can_sleep = true;
1671 
1672 	result = gpiochip_add_data(&priv->gc, serial);
1673 	if (!result)
1674 		priv->gpio_registered = true;
1675 
1676 	return result;
1677 }
1678 
1679 static void cp210x_gpio_remove(struct usb_serial *serial)
1680 {
1681 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1682 
1683 	if (priv->gpio_registered) {
1684 		gpiochip_remove(&priv->gc);
1685 		priv->gpio_registered = false;
1686 	}
1687 }
1688 
1689 #else
1690 
1691 static int cp210x_gpio_init(struct usb_serial *serial)
1692 {
1693 	return 0;
1694 }
1695 
1696 static void cp210x_gpio_remove(struct usb_serial *serial)
1697 {
1698 	/* Nothing to do */
1699 }
1700 
1701 #endif
1702 
1703 static int cp210x_port_probe(struct usb_serial_port *port)
1704 {
1705 	struct usb_serial *serial = port->serial;
1706 	struct cp210x_port_private *port_priv;
1707 
1708 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1709 	if (!port_priv)
1710 		return -ENOMEM;
1711 
1712 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1713 
1714 	usb_set_serial_port_data(port, port_priv);
1715 
1716 	return 0;
1717 }
1718 
1719 static int cp210x_port_remove(struct usb_serial_port *port)
1720 {
1721 	struct cp210x_port_private *port_priv;
1722 
1723 	port_priv = usb_get_serial_port_data(port);
1724 	kfree(port_priv);
1725 
1726 	return 0;
1727 }
1728 
1729 static void cp210x_init_max_speed(struct usb_serial *serial)
1730 {
1731 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1732 	bool use_actual_rate = false;
1733 	speed_t min = 300;
1734 	speed_t max;
1735 
1736 	switch (priv->partnum) {
1737 	case CP210X_PARTNUM_CP2101:
1738 		max = 921600;
1739 		break;
1740 	case CP210X_PARTNUM_CP2102:
1741 	case CP210X_PARTNUM_CP2103:
1742 		max = 1000000;
1743 		break;
1744 	case CP210X_PARTNUM_CP2104:
1745 		use_actual_rate = true;
1746 		max = 2000000;
1747 		break;
1748 	case CP210X_PARTNUM_CP2108:
1749 		max = 2000000;
1750 		break;
1751 	case CP210X_PARTNUM_CP2105:
1752 		if (cp210x_interface_num(serial) == 0) {
1753 			use_actual_rate = true;
1754 			max = 2000000;	/* ECI */
1755 		} else {
1756 			min = 2400;
1757 			max = 921600;	/* SCI */
1758 		}
1759 		break;
1760 	case CP210X_PARTNUM_CP2102N_QFN28:
1761 	case CP210X_PARTNUM_CP2102N_QFN24:
1762 	case CP210X_PARTNUM_CP2102N_QFN20:
1763 		use_actual_rate = true;
1764 		max = 3000000;
1765 		break;
1766 	default:
1767 		max = 2000000;
1768 		break;
1769 	}
1770 
1771 	priv->min_speed = min;
1772 	priv->max_speed = max;
1773 	priv->use_actual_rate = use_actual_rate;
1774 }
1775 
1776 static int cp210x_attach(struct usb_serial *serial)
1777 {
1778 	int result;
1779 	struct cp210x_serial_private *priv;
1780 
1781 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1782 	if (!priv)
1783 		return -ENOMEM;
1784 
1785 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1786 					  CP210X_GET_PARTNUM, &priv->partnum,
1787 					  sizeof(priv->partnum));
1788 	if (result < 0) {
1789 		dev_warn(&serial->interface->dev,
1790 			 "querying part number failed\n");
1791 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1792 	}
1793 
1794 	usb_set_serial_data(serial, priv);
1795 
1796 	cp210x_init_max_speed(serial);
1797 
1798 	result = cp210x_gpio_init(serial);
1799 	if (result < 0) {
1800 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1801 				result);
1802 	}
1803 
1804 	return 0;
1805 }
1806 
1807 static void cp210x_disconnect(struct usb_serial *serial)
1808 {
1809 	cp210x_gpio_remove(serial);
1810 }
1811 
1812 static void cp210x_release(struct usb_serial *serial)
1813 {
1814 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1815 
1816 	cp210x_gpio_remove(serial);
1817 
1818 	kfree(priv);
1819 }
1820 
1821 module_usb_serial_driver(serial_drivers, id_table);
1822 
1823 MODULE_DESCRIPTION(DRIVER_DESC);
1824 MODULE_LICENSE("GPL v2");
1825