xref: /linux/drivers/usb/serial/cp210x.c (revision ba4bbdabecd11530dca78dbae3ee7e51ffdc0a06)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Silicon Laboratories CP210x USB to RS232 serial adaptor driver
4  *
5  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
6  * Copyright (C) 2010-2021 Johan Hovold (johan@kernel.org)
7  *
8  * Support to set flow control line levels using TIOCMGET and TIOCMSET
9  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
10  * control thanks to Munir Nassar nassarmu@real-time.com
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/module.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/gpio/driver.h>
23 #include <linux/bitops.h>
24 #include <linux/mutex.h>
25 
26 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
27 
28 /*
29  * Function Prototypes
30  */
31 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
32 static void cp210x_close(struct usb_serial_port *);
33 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
34 							struct ktermios *);
35 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
36 							struct ktermios*);
37 static bool cp210x_tx_empty(struct usb_serial_port *port);
38 static int cp210x_tiocmget(struct tty_struct *);
39 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
40 static int cp210x_tiocmset_port(struct usb_serial_port *port,
41 		unsigned int, unsigned int);
42 static void cp210x_break_ctl(struct tty_struct *, int);
43 static int cp210x_attach(struct usb_serial *);
44 static void cp210x_disconnect(struct usb_serial *);
45 static void cp210x_release(struct usb_serial *);
46 static int cp210x_port_probe(struct usb_serial_port *);
47 static void cp210x_port_remove(struct usb_serial_port *);
48 static void cp210x_dtr_rts(struct usb_serial_port *port, int on);
49 static void cp210x_process_read_urb(struct urb *urb);
50 static void cp210x_enable_event_mode(struct usb_serial_port *port);
51 static void cp210x_disable_event_mode(struct usb_serial_port *port);
52 
53 static const struct usb_device_id id_table[] = {
54 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
55 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
56 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
57 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
58 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
59 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
60 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
61 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
62 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
63 	{ USB_DEVICE(0x0988, 0x0578) }, /* Teraoka AD2000 */
64 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
65 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
66 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
67 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
68 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
69 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
71 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
72 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
73 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
74 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
75 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
76 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
77 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
78 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
79 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
80 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
81 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
82 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
83 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
84 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
85 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
86 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
87 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
88 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
89 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
90 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
91 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
92 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
93 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
94 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
95 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
96 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
97 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
98 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
99 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
100 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
104 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
105 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
106 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
107 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
108 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
109 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
110 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
111 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
112 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
113 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
114 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
115 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
116 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
117 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
118 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
119 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
120 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
121 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
122 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
123 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
124 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
125 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
126 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
127 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
128 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
129 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
130 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
131 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
132 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
133 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
134 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
135 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
136 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
137 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
138 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
139 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
140 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
141 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
142 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
143 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
144 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
145 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
146 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
147 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
148 	{ USB_DEVICE(0x10C4, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
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, 0x8A5B) }, /* CEL EM3588 ZigBee USB Stick */
159 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
160 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
161 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
162 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
163 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
164 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
165 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
166 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
167 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
168 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
169 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
170 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
171 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
172 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
173 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
174 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
175 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
176 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
177 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
178 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
179 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
180 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
181 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
182 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
183 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
184 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
185 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
186 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
187 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
188 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
189 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
190 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
191 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
192 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
193 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
194 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
195 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
196 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
197 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
198 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
199 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
200 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
201 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
202 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
203 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
204 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
205 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
206 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 M.2 Key E serial interface */
207 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 Display serial interface */
208 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
209 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
210 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
211 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
212 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
213 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
214 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
215 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
216 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
217 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
218 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
219 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
220 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
221 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
222 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
223 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
224 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
225 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
226 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
227 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
228 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
229 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
230 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
231 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
232 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
233 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
234 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
235 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
236 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
237 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
238 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
239 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
240 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
241 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
242 	{ } /* Terminating Entry */
243 };
244 
245 MODULE_DEVICE_TABLE(usb, id_table);
246 
247 struct cp210x_serial_private {
248 #ifdef CONFIG_GPIOLIB
249 	struct gpio_chip	gc;
250 	bool			gpio_registered;
251 	u16			gpio_pushpull;
252 	u16			gpio_altfunc;
253 	u16			gpio_input;
254 #endif
255 	u8			partnum;
256 	u32			fw_version;
257 	speed_t			min_speed;
258 	speed_t			max_speed;
259 	bool			use_actual_rate;
260 	bool			no_flow_control;
261 };
262 
263 enum cp210x_event_state {
264 	ES_DATA,
265 	ES_ESCAPE,
266 	ES_LSR,
267 	ES_LSR_DATA_0,
268 	ES_LSR_DATA_1,
269 	ES_MSR
270 };
271 
272 struct cp210x_port_private {
273 	u8			bInterfaceNumber;
274 	bool			event_mode;
275 	enum cp210x_event_state event_state;
276 	u8			lsr;
277 
278 	struct mutex		mutex;
279 	bool			crtscts;
280 	bool			dtr;
281 	bool			rts;
282 };
283 
284 static struct usb_serial_driver cp210x_device = {
285 	.driver = {
286 		.owner =	THIS_MODULE,
287 		.name =		"cp210x",
288 	},
289 	.id_table		= id_table,
290 	.num_ports		= 1,
291 	.bulk_in_size		= 256,
292 	.bulk_out_size		= 256,
293 	.open			= cp210x_open,
294 	.close			= cp210x_close,
295 	.break_ctl		= cp210x_break_ctl,
296 	.set_termios		= cp210x_set_termios,
297 	.tx_empty		= cp210x_tx_empty,
298 	.throttle		= usb_serial_generic_throttle,
299 	.unthrottle		= usb_serial_generic_unthrottle,
300 	.tiocmget		= cp210x_tiocmget,
301 	.tiocmset		= cp210x_tiocmset,
302 	.get_icount		= usb_serial_generic_get_icount,
303 	.attach			= cp210x_attach,
304 	.disconnect		= cp210x_disconnect,
305 	.release		= cp210x_release,
306 	.port_probe		= cp210x_port_probe,
307 	.port_remove		= cp210x_port_remove,
308 	.dtr_rts		= cp210x_dtr_rts,
309 	.process_read_urb	= cp210x_process_read_urb,
310 };
311 
312 static struct usb_serial_driver * const serial_drivers[] = {
313 	&cp210x_device, NULL
314 };
315 
316 /* Config request types */
317 #define REQTYPE_HOST_TO_INTERFACE	0x41
318 #define REQTYPE_INTERFACE_TO_HOST	0xc1
319 #define REQTYPE_HOST_TO_DEVICE	0x40
320 #define REQTYPE_DEVICE_TO_HOST	0xc0
321 
322 /* Config request codes */
323 #define CP210X_IFC_ENABLE	0x00
324 #define CP210X_SET_BAUDDIV	0x01
325 #define CP210X_GET_BAUDDIV	0x02
326 #define CP210X_SET_LINE_CTL	0x03
327 #define CP210X_GET_LINE_CTL	0x04
328 #define CP210X_SET_BREAK	0x05
329 #define CP210X_IMM_CHAR		0x06
330 #define CP210X_SET_MHS		0x07
331 #define CP210X_GET_MDMSTS	0x08
332 #define CP210X_SET_XON		0x09
333 #define CP210X_SET_XOFF		0x0A
334 #define CP210X_SET_EVENTMASK	0x0B
335 #define CP210X_GET_EVENTMASK	0x0C
336 #define CP210X_SET_CHAR		0x0D
337 #define CP210X_GET_CHARS	0x0E
338 #define CP210X_GET_PROPS	0x0F
339 #define CP210X_GET_COMM_STATUS	0x10
340 #define CP210X_RESET		0x11
341 #define CP210X_PURGE		0x12
342 #define CP210X_SET_FLOW		0x13
343 #define CP210X_GET_FLOW		0x14
344 #define CP210X_EMBED_EVENTS	0x15
345 #define CP210X_GET_EVENTSTATE	0x16
346 #define CP210X_SET_CHARS	0x19
347 #define CP210X_GET_BAUDRATE	0x1D
348 #define CP210X_SET_BAUDRATE	0x1E
349 #define CP210X_VENDOR_SPECIFIC	0xFF
350 
351 /* CP210X_IFC_ENABLE */
352 #define UART_ENABLE		0x0001
353 #define UART_DISABLE		0x0000
354 
355 /* CP210X_(SET|GET)_BAUDDIV */
356 #define BAUD_RATE_GEN_FREQ	0x384000
357 
358 /* CP210X_(SET|GET)_LINE_CTL */
359 #define BITS_DATA_MASK		0X0f00
360 #define BITS_DATA_5		0X0500
361 #define BITS_DATA_6		0X0600
362 #define BITS_DATA_7		0X0700
363 #define BITS_DATA_8		0X0800
364 #define BITS_DATA_9		0X0900
365 
366 #define BITS_PARITY_MASK	0x00f0
367 #define BITS_PARITY_NONE	0x0000
368 #define BITS_PARITY_ODD		0x0010
369 #define BITS_PARITY_EVEN	0x0020
370 #define BITS_PARITY_MARK	0x0030
371 #define BITS_PARITY_SPACE	0x0040
372 
373 #define BITS_STOP_MASK		0x000f
374 #define BITS_STOP_1		0x0000
375 #define BITS_STOP_1_5		0x0001
376 #define BITS_STOP_2		0x0002
377 
378 /* CP210X_SET_BREAK */
379 #define BREAK_ON		0x0001
380 #define BREAK_OFF		0x0000
381 
382 /* CP210X_(SET_MHS|GET_MDMSTS) */
383 #define CONTROL_DTR		0x0001
384 #define CONTROL_RTS		0x0002
385 #define CONTROL_CTS		0x0010
386 #define CONTROL_DSR		0x0020
387 #define CONTROL_RING		0x0040
388 #define CONTROL_DCD		0x0080
389 #define CONTROL_WRITE_DTR	0x0100
390 #define CONTROL_WRITE_RTS	0x0200
391 
392 /* CP210X_(GET|SET)_CHARS */
393 struct cp210x_special_chars {
394 	u8	bEofChar;
395 	u8	bErrorChar;
396 	u8	bBreakChar;
397 	u8	bEventChar;
398 	u8	bXonChar;
399 	u8	bXoffChar;
400 };
401 
402 /* CP210X_VENDOR_SPECIFIC values */
403 #define CP210X_READ_2NCONFIG	0x000E
404 #define CP210X_GET_FW_VER_2N	0x0010
405 #define CP210X_READ_LATCH	0x00C2
406 #define CP210X_GET_PARTNUM	0x370B
407 #define CP210X_GET_PORTCONFIG	0x370C
408 #define CP210X_GET_DEVICEMODE	0x3711
409 #define CP210X_WRITE_LATCH	0x37E1
410 
411 /* Part number definitions */
412 #define CP210X_PARTNUM_CP2101	0x01
413 #define CP210X_PARTNUM_CP2102	0x02
414 #define CP210X_PARTNUM_CP2103	0x03
415 #define CP210X_PARTNUM_CP2104	0x04
416 #define CP210X_PARTNUM_CP2105	0x05
417 #define CP210X_PARTNUM_CP2108	0x08
418 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
419 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
420 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
421 #define CP210X_PARTNUM_UNKNOWN	0xFF
422 
423 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
424 struct cp210x_comm_status {
425 	__le32   ulErrors;
426 	__le32   ulHoldReasons;
427 	__le32   ulAmountInInQueue;
428 	__le32   ulAmountInOutQueue;
429 	u8       bEofReceived;
430 	u8       bWaitForImmediate;
431 	u8       bReserved;
432 } __packed;
433 
434 /*
435  * CP210X_PURGE - 16 bits passed in wValue of USB request.
436  * SiLabs app note AN571 gives a strange description of the 4 bits:
437  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
438  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
439  */
440 #define PURGE_ALL		0x000f
441 
442 /* CP210X_EMBED_EVENTS */
443 #define CP210X_ESCCHAR		0xec
444 
445 #define CP210X_LSR_OVERRUN	BIT(1)
446 #define CP210X_LSR_PARITY	BIT(2)
447 #define CP210X_LSR_FRAME	BIT(3)
448 #define CP210X_LSR_BREAK	BIT(4)
449 
450 
451 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
452 struct cp210x_flow_ctl {
453 	__le32	ulControlHandshake;
454 	__le32	ulFlowReplace;
455 	__le32	ulXonLimit;
456 	__le32	ulXoffLimit;
457 };
458 
459 /* cp210x_flow_ctl::ulControlHandshake */
460 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
461 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
462 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
463 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
464 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
465 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
466 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
467 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
468 
469 /* cp210x_flow_ctl::ulFlowReplace */
470 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
471 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
472 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
473 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
474 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
475 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
476 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
477 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
478 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
479 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
480 
481 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
482 struct cp210x_pin_mode {
483 	u8	eci;
484 	u8	sci;
485 };
486 
487 #define CP210X_PIN_MODE_MODEM		0
488 #define CP210X_PIN_MODE_GPIO		BIT(0)
489 
490 /*
491  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
492  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
493  */
494 struct cp210x_dual_port_config {
495 	__le16	gpio_mode;
496 	u8	__pad0[2];
497 	__le16	reset_state;
498 	u8	__pad1[4];
499 	__le16	suspend_state;
500 	u8	sci_cfg;
501 	u8	eci_cfg;
502 	u8	device_cfg;
503 } __packed;
504 
505 /*
506  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
507  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
508  */
509 struct cp210x_single_port_config {
510 	__le16	gpio_mode;
511 	u8	__pad0[2];
512 	__le16	reset_state;
513 	u8	__pad1[4];
514 	__le16	suspend_state;
515 	u8	device_cfg;
516 } __packed;
517 
518 /* GPIO modes */
519 #define CP210X_SCI_GPIO_MODE_OFFSET	9
520 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
521 
522 #define CP210X_ECI_GPIO_MODE_OFFSET	2
523 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
524 
525 #define CP210X_GPIO_MODE_OFFSET		8
526 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
527 
528 /* CP2105 port configuration values */
529 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
530 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
531 #define CP2105_GPIO1_RS485_MODE		BIT(2)
532 
533 /* CP2104 port configuration values */
534 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
535 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
536 #define CP2104_GPIO2_RS485_MODE		BIT(2)
537 
538 struct cp210x_quad_port_state {
539 	__le16 gpio_mode_pb0;
540 	__le16 gpio_mode_pb1;
541 	__le16 gpio_mode_pb2;
542 	__le16 gpio_mode_pb3;
543 	__le16 gpio_mode_pb4;
544 
545 	__le16 gpio_lowpower_pb0;
546 	__le16 gpio_lowpower_pb1;
547 	__le16 gpio_lowpower_pb2;
548 	__le16 gpio_lowpower_pb3;
549 	__le16 gpio_lowpower_pb4;
550 
551 	__le16 gpio_latch_pb0;
552 	__le16 gpio_latch_pb1;
553 	__le16 gpio_latch_pb2;
554 	__le16 gpio_latch_pb3;
555 	__le16 gpio_latch_pb4;
556 };
557 
558 /*
559  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
560  * on a CP2108 chip.
561  *
562  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
563  */
564 struct cp210x_quad_port_config {
565 	struct cp210x_quad_port_state reset_state;
566 	struct cp210x_quad_port_state suspend_state;
567 	u8 ipdelay_ifc[4];
568 	u8 enhancedfxn_ifc[4];
569 	u8 enhancedfxn_device;
570 	u8 extclkfreq[4];
571 } __packed;
572 
573 #define CP2108_EF_IFC_GPIO_TXLED		0x01
574 #define CP2108_EF_IFC_GPIO_RXLED		0x02
575 #define CP2108_EF_IFC_GPIO_RS485		0x04
576 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
577 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
578 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
579 
580 /* CP2102N configuration array indices */
581 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
582 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
583 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
584 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
585 
586 /* CP2102N QFN20 port configuration values */
587 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
588 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
589 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
590 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
591 
592 /*
593  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
594  * for CP2102N, CP2103, CP2104 and CP2105.
595  */
596 struct cp210x_gpio_write {
597 	u8	mask;
598 	u8	state;
599 };
600 
601 /*
602  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
603  * for CP2108.
604  */
605 struct cp210x_gpio_write16 {
606 	__le16	mask;
607 	__le16	state;
608 };
609 
610 /*
611  * Helper to get interface number when we only have struct usb_serial.
612  */
613 static u8 cp210x_interface_num(struct usb_serial *serial)
614 {
615 	struct usb_host_interface *cur_altsetting;
616 
617 	cur_altsetting = serial->interface->cur_altsetting;
618 
619 	return cur_altsetting->desc.bInterfaceNumber;
620 }
621 
622 /*
623  * Reads a variable-sized block of CP210X_ registers, identified by req.
624  * Returns data into buf in native USB byte order.
625  */
626 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
627 		void *buf, int bufsize)
628 {
629 	struct usb_serial *serial = port->serial;
630 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
631 	void *dmabuf;
632 	int result;
633 
634 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
635 	if (!dmabuf)
636 		return -ENOMEM;
637 
638 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
639 			req, REQTYPE_INTERFACE_TO_HOST, 0,
640 			port_priv->bInterfaceNumber, dmabuf, bufsize,
641 			USB_CTRL_SET_TIMEOUT);
642 	if (result == bufsize) {
643 		memcpy(buf, dmabuf, bufsize);
644 		result = 0;
645 	} else {
646 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
647 				req, bufsize, result);
648 		if (result >= 0)
649 			result = -EIO;
650 	}
651 
652 	kfree(dmabuf);
653 
654 	return result;
655 }
656 
657 /*
658  * Reads any 8-bit CP210X_ register identified by req.
659  */
660 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
661 {
662 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
663 }
664 
665 /*
666  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
667  * Returns data into buf in native USB byte order.
668  */
669 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
670 				    void *buf, int bufsize)
671 {
672 	void *dmabuf;
673 	int result;
674 
675 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
676 	if (!dmabuf)
677 		return -ENOMEM;
678 
679 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
680 				 CP210X_VENDOR_SPECIFIC, type, val,
681 				 cp210x_interface_num(serial), dmabuf, bufsize,
682 				 USB_CTRL_GET_TIMEOUT);
683 	if (result == bufsize) {
684 		memcpy(buf, dmabuf, bufsize);
685 		result = 0;
686 	} else {
687 		dev_err(&serial->interface->dev,
688 			"failed to get vendor val 0x%04x size %d: %d\n", val,
689 			bufsize, result);
690 		if (result >= 0)
691 			result = -EIO;
692 	}
693 
694 	kfree(dmabuf);
695 
696 	return result;
697 }
698 
699 /*
700  * Writes any 16-bit CP210X_ register (req) whose value is passed
701  * entirely in the wValue field of the USB request.
702  */
703 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
704 {
705 	struct usb_serial *serial = port->serial;
706 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
707 	int result;
708 
709 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
710 			req, REQTYPE_HOST_TO_INTERFACE, val,
711 			port_priv->bInterfaceNumber, NULL, 0,
712 			USB_CTRL_SET_TIMEOUT);
713 	if (result < 0) {
714 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
715 				req, result);
716 	}
717 
718 	return result;
719 }
720 
721 /*
722  * Writes a variable-sized block of CP210X_ registers, identified by req.
723  * Data in buf must be in native USB byte order.
724  */
725 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
726 		void *buf, int bufsize)
727 {
728 	struct usb_serial *serial = port->serial;
729 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
730 	void *dmabuf;
731 	int result;
732 
733 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
734 	if (!dmabuf)
735 		return -ENOMEM;
736 
737 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
738 			req, REQTYPE_HOST_TO_INTERFACE, 0,
739 			port_priv->bInterfaceNumber, dmabuf, bufsize,
740 			USB_CTRL_SET_TIMEOUT);
741 
742 	kfree(dmabuf);
743 
744 	if (result < 0) {
745 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
746 				req, bufsize, result);
747 		return result;
748 	}
749 
750 	return 0;
751 }
752 
753 /*
754  * Writes any 32-bit CP210X_ register identified by req.
755  */
756 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
757 {
758 	__le32 le32_val;
759 
760 	le32_val = cpu_to_le32(val);
761 
762 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
763 }
764 
765 #ifdef CONFIG_GPIOLIB
766 /*
767  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
768  * Data in buf must be in native USB byte order.
769  */
770 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
771 				     u16 val, void *buf, int bufsize)
772 {
773 	void *dmabuf;
774 	int result;
775 
776 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
777 	if (!dmabuf)
778 		return -ENOMEM;
779 
780 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
781 				 CP210X_VENDOR_SPECIFIC, type, val,
782 				 cp210x_interface_num(serial), dmabuf, bufsize,
783 				 USB_CTRL_SET_TIMEOUT);
784 
785 	kfree(dmabuf);
786 
787 	if (result < 0) {
788 		dev_err(&serial->interface->dev,
789 			"failed to set vendor val 0x%04x size %d: %d\n", val,
790 			bufsize, result);
791 		return result;
792 	}
793 
794 	return 0;
795 }
796 #endif
797 
798 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
799 {
800 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
801 	int result;
802 
803 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
804 	if (result) {
805 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
806 		return result;
807 	}
808 
809 	if (tty)
810 		cp210x_set_termios(tty, port, NULL);
811 
812 	result = usb_serial_generic_open(tty, port);
813 	if (result)
814 		goto err_disable;
815 
816 	return 0;
817 
818 err_disable:
819 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
820 	port_priv->event_mode = false;
821 
822 	return result;
823 }
824 
825 static void cp210x_close(struct usb_serial_port *port)
826 {
827 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
828 
829 	usb_serial_generic_close(port);
830 
831 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
832 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
833 
834 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
835 
836 	/* Disabling the interface disables event-insertion mode. */
837 	port_priv->event_mode = false;
838 }
839 
840 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
841 {
842 	if (lsr & CP210X_LSR_BREAK) {
843 		port->icount.brk++;
844 		*flag = TTY_BREAK;
845 	} else if (lsr & CP210X_LSR_PARITY) {
846 		port->icount.parity++;
847 		*flag = TTY_PARITY;
848 	} else if (lsr & CP210X_LSR_FRAME) {
849 		port->icount.frame++;
850 		*flag = TTY_FRAME;
851 	}
852 
853 	if (lsr & CP210X_LSR_OVERRUN) {
854 		port->icount.overrun++;
855 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
856 	}
857 }
858 
859 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
860 {
861 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
862 
863 	switch (port_priv->event_state) {
864 	case ES_DATA:
865 		if (*ch == CP210X_ESCCHAR) {
866 			port_priv->event_state = ES_ESCAPE;
867 			break;
868 		}
869 		return false;
870 	case ES_ESCAPE:
871 		switch (*ch) {
872 		case 0:
873 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
874 			*ch = CP210X_ESCCHAR;
875 			port_priv->event_state = ES_DATA;
876 			return false;
877 		case 1:
878 			port_priv->event_state = ES_LSR_DATA_0;
879 			break;
880 		case 2:
881 			port_priv->event_state = ES_LSR;
882 			break;
883 		case 3:
884 			port_priv->event_state = ES_MSR;
885 			break;
886 		default:
887 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
888 			port_priv->event_state = ES_DATA;
889 			break;
890 		}
891 		break;
892 	case ES_LSR_DATA_0:
893 		port_priv->lsr = *ch;
894 		port_priv->event_state = ES_LSR_DATA_1;
895 		break;
896 	case ES_LSR_DATA_1:
897 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
898 				__func__, port_priv->lsr, *ch);
899 		cp210x_process_lsr(port, port_priv->lsr, flag);
900 		port_priv->event_state = ES_DATA;
901 		return false;
902 	case ES_LSR:
903 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
904 		port_priv->lsr = *ch;
905 		cp210x_process_lsr(port, port_priv->lsr, flag);
906 		port_priv->event_state = ES_DATA;
907 		break;
908 	case ES_MSR:
909 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
910 		/* unimplemented */
911 		port_priv->event_state = ES_DATA;
912 		break;
913 	}
914 
915 	return true;
916 }
917 
918 static void cp210x_process_read_urb(struct urb *urb)
919 {
920 	struct usb_serial_port *port = urb->context;
921 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
922 	unsigned char *ch = urb->transfer_buffer;
923 	char flag;
924 	int i;
925 
926 	if (!urb->actual_length)
927 		return;
928 
929 	if (port_priv->event_mode) {
930 		for (i = 0; i < urb->actual_length; i++, ch++) {
931 			flag = TTY_NORMAL;
932 
933 			if (cp210x_process_char(port, ch, &flag))
934 				continue;
935 
936 			tty_insert_flip_char(&port->port, *ch, flag);
937 		}
938 	} else {
939 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
940 	}
941 	tty_flip_buffer_push(&port->port);
942 }
943 
944 /*
945  * Read how many bytes are waiting in the TX queue.
946  */
947 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
948 		u32 *count)
949 {
950 	struct usb_serial *serial = port->serial;
951 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
952 	struct cp210x_comm_status *sts;
953 	int result;
954 
955 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
956 	if (!sts)
957 		return -ENOMEM;
958 
959 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
960 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
961 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
962 			USB_CTRL_GET_TIMEOUT);
963 	if (result == sizeof(*sts)) {
964 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
965 		result = 0;
966 	} else {
967 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
968 		if (result >= 0)
969 			result = -EIO;
970 	}
971 
972 	kfree(sts);
973 
974 	return result;
975 }
976 
977 static bool cp210x_tx_empty(struct usb_serial_port *port)
978 {
979 	int err;
980 	u32 count;
981 
982 	err = cp210x_get_tx_queue_byte_count(port, &count);
983 	if (err)
984 		return true;
985 
986 	return !count;
987 }
988 
989 struct cp210x_rate {
990 	speed_t rate;
991 	speed_t high;
992 };
993 
994 static const struct cp210x_rate cp210x_an205_table1[] = {
995 	{ 300, 300 },
996 	{ 600, 600 },
997 	{ 1200, 1200 },
998 	{ 1800, 1800 },
999 	{ 2400, 2400 },
1000 	{ 4000, 4000 },
1001 	{ 4800, 4803 },
1002 	{ 7200, 7207 },
1003 	{ 9600, 9612 },
1004 	{ 14400, 14428 },
1005 	{ 16000, 16062 },
1006 	{ 19200, 19250 },
1007 	{ 28800, 28912 },
1008 	{ 38400, 38601 },
1009 	{ 51200, 51558 },
1010 	{ 56000, 56280 },
1011 	{ 57600, 58053 },
1012 	{ 64000, 64111 },
1013 	{ 76800, 77608 },
1014 	{ 115200, 117028 },
1015 	{ 128000, 129347 },
1016 	{ 153600, 156868 },
1017 	{ 230400, 237832 },
1018 	{ 250000, 254234 },
1019 	{ 256000, 273066 },
1020 	{ 460800, 491520 },
1021 	{ 500000, 567138 },
1022 	{ 576000, 670254 },
1023 	{ 921600, UINT_MAX }
1024 };
1025 
1026 /*
1027  * Quantises the baud rate as per AN205 Table 1
1028  */
1029 static speed_t cp210x_get_an205_rate(speed_t baud)
1030 {
1031 	int i;
1032 
1033 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1034 		if (baud <= cp210x_an205_table1[i].high)
1035 			break;
1036 	}
1037 
1038 	return cp210x_an205_table1[i].rate;
1039 }
1040 
1041 static speed_t cp210x_get_actual_rate(speed_t baud)
1042 {
1043 	unsigned int prescale = 1;
1044 	unsigned int div;
1045 
1046 	if (baud <= 365)
1047 		prescale = 4;
1048 
1049 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1050 	baud = 48000000 / (2 * prescale * div);
1051 
1052 	return baud;
1053 }
1054 
1055 /*
1056  * CP2101 supports the following baud rates:
1057  *
1058  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1059  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1060  *
1061  * CP2102 and CP2103 support the following additional rates:
1062  *
1063  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1064  *	576000
1065  *
1066  * The device will map a requested rate to a supported one, but the result
1067  * of requests for rates greater than 1053257 is undefined (see AN205).
1068  *
1069  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1070  * respectively, with an error less than 1%. The actual rates are determined
1071  * by
1072  *
1073  *	div = round(freq / (2 x prescale x request))
1074  *	actual = freq / (2 x prescale x div)
1075  *
1076  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1077  * or 1 otherwise.
1078  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1079  * otherwise.
1080  */
1081 static void cp210x_change_speed(struct tty_struct *tty,
1082 		struct usb_serial_port *port, struct ktermios *old_termios)
1083 {
1084 	struct usb_serial *serial = port->serial;
1085 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1086 	u32 baud;
1087 
1088 	/*
1089 	 * This maps the requested rate to the actual rate, a valid rate on
1090 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1091 	 *
1092 	 * NOTE: B0 is not implemented.
1093 	 */
1094 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1095 
1096 	if (priv->use_actual_rate)
1097 		baud = cp210x_get_actual_rate(baud);
1098 	else if (baud < 1000000)
1099 		baud = cp210x_get_an205_rate(baud);
1100 
1101 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1102 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1103 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1104 		if (old_termios)
1105 			baud = old_termios->c_ospeed;
1106 		else
1107 			baud = 9600;
1108 	}
1109 
1110 	tty_encode_baud_rate(tty, baud, baud);
1111 }
1112 
1113 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1114 {
1115 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1116 	int ret;
1117 
1118 	if (port_priv->event_mode)
1119 		return;
1120 
1121 	port_priv->event_state = ES_DATA;
1122 	port_priv->event_mode = true;
1123 
1124 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1125 	if (ret) {
1126 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1127 		port_priv->event_mode = false;
1128 	}
1129 }
1130 
1131 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1132 {
1133 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1134 	int ret;
1135 
1136 	if (!port_priv->event_mode)
1137 		return;
1138 
1139 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1140 	if (ret) {
1141 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1142 		return;
1143 	}
1144 
1145 	port_priv->event_mode = false;
1146 }
1147 
1148 static int cp210x_set_chars(struct usb_serial_port *port,
1149 		struct cp210x_special_chars *chars)
1150 {
1151 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1152 	struct usb_serial *serial = port->serial;
1153 	void *dmabuf;
1154 	int result;
1155 
1156 	dmabuf = kmemdup(chars, sizeof(*chars), GFP_KERNEL);
1157 	if (!dmabuf)
1158 		return -ENOMEM;
1159 
1160 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1161 				CP210X_SET_CHARS, REQTYPE_HOST_TO_INTERFACE, 0,
1162 				port_priv->bInterfaceNumber,
1163 				dmabuf, sizeof(*chars), USB_CTRL_SET_TIMEOUT);
1164 
1165 	kfree(dmabuf);
1166 
1167 	if (result < 0)
1168 		return result;
1169 
1170 	return 0;
1171 }
1172 
1173 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1174 {
1175 	bool iflag_change, cc_change;
1176 
1177 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1178 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1179 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1180 
1181 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1182 }
1183 
1184 static void cp210x_set_flow_control(struct tty_struct *tty,
1185 		struct usb_serial_port *port, struct ktermios *old_termios)
1186 {
1187 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1188 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1189 	struct cp210x_special_chars chars;
1190 	struct cp210x_flow_ctl flow_ctl;
1191 	u32 flow_repl;
1192 	u32 ctl_hs;
1193 	bool crtscts;
1194 	int ret;
1195 
1196 	/*
1197 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1198 	 * CP2102N_E104). Report back that flow control is not supported.
1199 	 */
1200 	if (priv->no_flow_control) {
1201 		tty->termios.c_cflag &= ~CRTSCTS;
1202 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1203 	}
1204 
1205 	if (old_termios &&
1206 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1207 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1208 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1209 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1210 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1211 		return;
1212 	}
1213 
1214 	if (I_IXON(tty) || I_IXOFF(tty)) {
1215 		memset(&chars, 0, sizeof(chars));
1216 
1217 		chars.bXonChar = START_CHAR(tty);
1218 		chars.bXoffChar = STOP_CHAR(tty);
1219 
1220 		ret = cp210x_set_chars(port, &chars);
1221 		if (ret) {
1222 			dev_err(&port->dev, "failed to set special chars: %d\n",
1223 					ret);
1224 		}
1225 	}
1226 
1227 	mutex_lock(&port_priv->mutex);
1228 
1229 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1230 			sizeof(flow_ctl));
1231 	if (ret)
1232 		goto out_unlock;
1233 
1234 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1235 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1236 
1237 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1238 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1239 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1240 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1241 	if (port_priv->dtr)
1242 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1243 	else
1244 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1245 
1246 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1247 	if (C_CRTSCTS(tty)) {
1248 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1249 		if (port_priv->rts)
1250 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1251 		else
1252 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1253 		crtscts = true;
1254 	} else {
1255 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1256 		if (port_priv->rts)
1257 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1258 		else
1259 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1260 		crtscts = false;
1261 	}
1262 
1263 	if (I_IXOFF(tty)) {
1264 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1265 
1266 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1267 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1268 	} else {
1269 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1270 	}
1271 
1272 	if (I_IXON(tty))
1273 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1274 	else
1275 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1276 
1277 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1278 			ctl_hs, flow_repl);
1279 
1280 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1281 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1282 
1283 	ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1284 			sizeof(flow_ctl));
1285 	if (ret)
1286 		goto out_unlock;
1287 
1288 	port_priv->crtscts = crtscts;
1289 out_unlock:
1290 	mutex_unlock(&port_priv->mutex);
1291 }
1292 
1293 static void cp210x_set_termios(struct tty_struct *tty,
1294 		struct usb_serial_port *port, struct ktermios *old_termios)
1295 {
1296 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1297 	u16 bits;
1298 	int ret;
1299 
1300 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1301 		return;
1302 
1303 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1304 		cp210x_change_speed(tty, port, old_termios);
1305 
1306 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1307 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1308 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1309 		tty->termios.c_cflag |= CS8;
1310 	}
1311 
1312 	bits = 0;
1313 
1314 	switch (C_CSIZE(tty)) {
1315 	case CS5:
1316 		bits |= BITS_DATA_5;
1317 		break;
1318 	case CS6:
1319 		bits |= BITS_DATA_6;
1320 		break;
1321 	case CS7:
1322 		bits |= BITS_DATA_7;
1323 		break;
1324 	case CS8:
1325 	default:
1326 		bits |= BITS_DATA_8;
1327 		break;
1328 	}
1329 
1330 	if (C_PARENB(tty)) {
1331 		if (C_CMSPAR(tty)) {
1332 			if (C_PARODD(tty))
1333 				bits |= BITS_PARITY_MARK;
1334 			else
1335 				bits |= BITS_PARITY_SPACE;
1336 		} else {
1337 			if (C_PARODD(tty))
1338 				bits |= BITS_PARITY_ODD;
1339 			else
1340 				bits |= BITS_PARITY_EVEN;
1341 		}
1342 	}
1343 
1344 	if (C_CSTOPB(tty))
1345 		bits |= BITS_STOP_2;
1346 	else
1347 		bits |= BITS_STOP_1;
1348 
1349 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1350 	if (ret)
1351 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1352 
1353 	cp210x_set_flow_control(tty, port, old_termios);
1354 
1355 	/*
1356 	 * Enable event-insertion mode only if input parity checking is
1357 	 * enabled for now.
1358 	 */
1359 	if (I_INPCK(tty))
1360 		cp210x_enable_event_mode(port);
1361 	else
1362 		cp210x_disable_event_mode(port);
1363 }
1364 
1365 static int cp210x_tiocmset(struct tty_struct *tty,
1366 		unsigned int set, unsigned int clear)
1367 {
1368 	struct usb_serial_port *port = tty->driver_data;
1369 	return cp210x_tiocmset_port(port, set, clear);
1370 }
1371 
1372 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1373 		unsigned int set, unsigned int clear)
1374 {
1375 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1376 	struct cp210x_flow_ctl flow_ctl;
1377 	u32 ctl_hs, flow_repl;
1378 	u16 control = 0;
1379 	int ret;
1380 
1381 	mutex_lock(&port_priv->mutex);
1382 
1383 	if (set & TIOCM_RTS) {
1384 		port_priv->rts = true;
1385 		control |= CONTROL_RTS;
1386 		control |= CONTROL_WRITE_RTS;
1387 	}
1388 	if (set & TIOCM_DTR) {
1389 		port_priv->dtr = true;
1390 		control |= CONTROL_DTR;
1391 		control |= CONTROL_WRITE_DTR;
1392 	}
1393 	if (clear & TIOCM_RTS) {
1394 		port_priv->rts = false;
1395 		control &= ~CONTROL_RTS;
1396 		control |= CONTROL_WRITE_RTS;
1397 	}
1398 	if (clear & TIOCM_DTR) {
1399 		port_priv->dtr = false;
1400 		control &= ~CONTROL_DTR;
1401 		control |= CONTROL_WRITE_DTR;
1402 	}
1403 
1404 	/*
1405 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1406 	 * flow control is enabled.
1407 	 */
1408 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1409 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1410 				sizeof(flow_ctl));
1411 		if (ret)
1412 			goto out_unlock;
1413 
1414 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1415 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1416 
1417 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1418 		if (port_priv->dtr)
1419 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1420 		else
1421 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1422 
1423 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1424 		if (port_priv->rts)
1425 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1426 		else
1427 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1428 
1429 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1430 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1431 
1432 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1433 				__func__, ctl_hs, flow_repl);
1434 
1435 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1436 				sizeof(flow_ctl));
1437 	} else {
1438 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1439 
1440 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1441 	}
1442 out_unlock:
1443 	mutex_unlock(&port_priv->mutex);
1444 
1445 	return ret;
1446 }
1447 
1448 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1449 {
1450 	if (on)
1451 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1452 	else
1453 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1454 }
1455 
1456 static int cp210x_tiocmget(struct tty_struct *tty)
1457 {
1458 	struct usb_serial_port *port = tty->driver_data;
1459 	u8 control;
1460 	int result;
1461 
1462 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1463 	if (result)
1464 		return result;
1465 
1466 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1467 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1468 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1469 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1470 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1471 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1472 
1473 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1474 
1475 	return result;
1476 }
1477 
1478 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1479 {
1480 	struct usb_serial_port *port = tty->driver_data;
1481 	u16 state;
1482 
1483 	if (break_state == 0)
1484 		state = BREAK_OFF;
1485 	else
1486 		state = BREAK_ON;
1487 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1488 		state == BREAK_OFF ? "off" : "on");
1489 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1490 }
1491 
1492 #ifdef CONFIG_GPIOLIB
1493 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1494 {
1495 	struct usb_serial *serial = gpiochip_get_data(gc);
1496 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1497 	u8 req_type;
1498 	u16 mask;
1499 	int result;
1500 	int len;
1501 
1502 	result = usb_autopm_get_interface(serial->interface);
1503 	if (result)
1504 		return result;
1505 
1506 	switch (priv->partnum) {
1507 	case CP210X_PARTNUM_CP2105:
1508 		req_type = REQTYPE_INTERFACE_TO_HOST;
1509 		len = 1;
1510 		break;
1511 	case CP210X_PARTNUM_CP2108:
1512 		req_type = REQTYPE_INTERFACE_TO_HOST;
1513 		len = 2;
1514 		break;
1515 	default:
1516 		req_type = REQTYPE_DEVICE_TO_HOST;
1517 		len = 1;
1518 		break;
1519 	}
1520 
1521 	mask = 0;
1522 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1523 					  &mask, len);
1524 
1525 	usb_autopm_put_interface(serial->interface);
1526 
1527 	if (result < 0)
1528 		return result;
1529 
1530 	le16_to_cpus(&mask);
1531 
1532 	return !!(mask & BIT(gpio));
1533 }
1534 
1535 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1536 {
1537 	struct usb_serial *serial = gpiochip_get_data(gc);
1538 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1539 	struct cp210x_gpio_write16 buf16;
1540 	struct cp210x_gpio_write buf;
1541 	u16 mask, state;
1542 	u16 wIndex;
1543 	int result;
1544 
1545 	if (value == 1)
1546 		state = BIT(gpio);
1547 	else
1548 		state = 0;
1549 
1550 	mask = BIT(gpio);
1551 
1552 	result = usb_autopm_get_interface(serial->interface);
1553 	if (result)
1554 		goto out;
1555 
1556 	switch (priv->partnum) {
1557 	case CP210X_PARTNUM_CP2105:
1558 		buf.mask = (u8)mask;
1559 		buf.state = (u8)state;
1560 		result = cp210x_write_vendor_block(serial,
1561 						   REQTYPE_HOST_TO_INTERFACE,
1562 						   CP210X_WRITE_LATCH, &buf,
1563 						   sizeof(buf));
1564 		break;
1565 	case CP210X_PARTNUM_CP2108:
1566 		buf16.mask = cpu_to_le16(mask);
1567 		buf16.state = cpu_to_le16(state);
1568 		result = cp210x_write_vendor_block(serial,
1569 						   REQTYPE_HOST_TO_INTERFACE,
1570 						   CP210X_WRITE_LATCH, &buf16,
1571 						   sizeof(buf16));
1572 		break;
1573 	default:
1574 		wIndex = state << 8 | mask;
1575 		result = usb_control_msg(serial->dev,
1576 					 usb_sndctrlpipe(serial->dev, 0),
1577 					 CP210X_VENDOR_SPECIFIC,
1578 					 REQTYPE_HOST_TO_DEVICE,
1579 					 CP210X_WRITE_LATCH,
1580 					 wIndex,
1581 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1582 		break;
1583 	}
1584 
1585 	usb_autopm_put_interface(serial->interface);
1586 out:
1587 	if (result < 0) {
1588 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1589 				result);
1590 	}
1591 }
1592 
1593 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1594 {
1595 	struct usb_serial *serial = gpiochip_get_data(gc);
1596 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1597 
1598 	return priv->gpio_input & BIT(gpio);
1599 }
1600 
1601 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1602 {
1603 	struct usb_serial *serial = gpiochip_get_data(gc);
1604 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1605 
1606 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1607 		/* hardware does not support an input mode */
1608 		return -ENOTSUPP;
1609 	}
1610 
1611 	/* push-pull pins cannot be changed to be inputs */
1612 	if (priv->gpio_pushpull & BIT(gpio))
1613 		return -EINVAL;
1614 
1615 	/* make sure to release pin if it is being driven low */
1616 	cp210x_gpio_set(gc, gpio, 1);
1617 
1618 	priv->gpio_input |= BIT(gpio);
1619 
1620 	return 0;
1621 }
1622 
1623 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1624 					int value)
1625 {
1626 	struct usb_serial *serial = gpiochip_get_data(gc);
1627 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1628 
1629 	priv->gpio_input &= ~BIT(gpio);
1630 	cp210x_gpio_set(gc, gpio, value);
1631 
1632 	return 0;
1633 }
1634 
1635 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1636 				  unsigned long config)
1637 {
1638 	struct usb_serial *serial = gpiochip_get_data(gc);
1639 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1640 	enum pin_config_param param = pinconf_to_config_param(config);
1641 
1642 	/* Succeed only if in correct mode (this can't be set at runtime) */
1643 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1644 	    (priv->gpio_pushpull & BIT(gpio)))
1645 		return 0;
1646 
1647 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1648 	    !(priv->gpio_pushpull & BIT(gpio)))
1649 		return 0;
1650 
1651 	return -ENOTSUPP;
1652 }
1653 
1654 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1655 		unsigned long *valid_mask, unsigned int ngpios)
1656 {
1657 	struct usb_serial *serial = gpiochip_get_data(gc);
1658 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1659 	struct device *dev = &serial->interface->dev;
1660 	unsigned long altfunc_mask = priv->gpio_altfunc;
1661 
1662 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1663 
1664 	if (bitmap_empty(valid_mask, ngpios))
1665 		dev_dbg(dev, "no pin configured for GPIO\n");
1666 	else
1667 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1668 				valid_mask);
1669 	return 0;
1670 }
1671 
1672 /*
1673  * This function is for configuring GPIO using shared pins, where other signals
1674  * are made unavailable by configuring the use of GPIO. This is believed to be
1675  * only applicable to the cp2105 at this point, the other devices supported by
1676  * this driver that provide GPIO do so in a way that does not impact other
1677  * signals and are thus expected to have very different initialisation.
1678  */
1679 static int cp2105_gpioconf_init(struct usb_serial *serial)
1680 {
1681 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1682 	struct cp210x_pin_mode mode;
1683 	struct cp210x_dual_port_config config;
1684 	u8 intf_num = cp210x_interface_num(serial);
1685 	u8 iface_config;
1686 	int result;
1687 
1688 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1689 					  CP210X_GET_DEVICEMODE, &mode,
1690 					  sizeof(mode));
1691 	if (result < 0)
1692 		return result;
1693 
1694 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1695 					  CP210X_GET_PORTCONFIG, &config,
1696 					  sizeof(config));
1697 	if (result < 0)
1698 		return result;
1699 
1700 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1701 	if (intf_num == 0) {
1702 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1703 			/* mark all GPIOs of this interface as reserved */
1704 			priv->gpio_altfunc = 0xff;
1705 			return 0;
1706 		}
1707 
1708 		iface_config = config.eci_cfg;
1709 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1710 						CP210X_ECI_GPIO_MODE_MASK) >>
1711 						CP210X_ECI_GPIO_MODE_OFFSET);
1712 		priv->gc.ngpio = 2;
1713 	} else if (intf_num == 1) {
1714 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1715 			/* mark all GPIOs of this interface as reserved */
1716 			priv->gpio_altfunc = 0xff;
1717 			return 0;
1718 		}
1719 
1720 		iface_config = config.sci_cfg;
1721 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1722 						CP210X_SCI_GPIO_MODE_MASK) >>
1723 						CP210X_SCI_GPIO_MODE_OFFSET);
1724 		priv->gc.ngpio = 3;
1725 	} else {
1726 		return -ENODEV;
1727 	}
1728 
1729 	/* mark all pins which are not in GPIO mode */
1730 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1731 		priv->gpio_altfunc |= BIT(0);
1732 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1733 			CP2105_GPIO1_RS485_MODE))
1734 		priv->gpio_altfunc |= BIT(1);
1735 
1736 	/* driver implementation for CP2105 only supports outputs */
1737 	priv->gpio_input = 0;
1738 
1739 	return 0;
1740 }
1741 
1742 static int cp2104_gpioconf_init(struct usb_serial *serial)
1743 {
1744 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1745 	struct cp210x_single_port_config config;
1746 	u8 iface_config;
1747 	u8 gpio_latch;
1748 	int result;
1749 	u8 i;
1750 
1751 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1752 					  CP210X_GET_PORTCONFIG, &config,
1753 					  sizeof(config));
1754 	if (result < 0)
1755 		return result;
1756 
1757 	priv->gc.ngpio = 4;
1758 
1759 	iface_config = config.device_cfg;
1760 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1761 					CP210X_GPIO_MODE_MASK) >>
1762 					CP210X_GPIO_MODE_OFFSET);
1763 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1764 					CP210X_GPIO_MODE_MASK) >>
1765 					CP210X_GPIO_MODE_OFFSET);
1766 
1767 	/* mark all pins which are not in GPIO mode */
1768 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1769 		priv->gpio_altfunc |= BIT(0);
1770 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1771 		priv->gpio_altfunc |= BIT(1);
1772 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1773 		priv->gpio_altfunc |= BIT(2);
1774 
1775 	/*
1776 	 * Like CP2102N, CP2104 has also no strict input and output pin
1777 	 * modes.
1778 	 * Do the same input mode emulation as CP2102N.
1779 	 */
1780 	for (i = 0; i < priv->gc.ngpio; ++i) {
1781 		/*
1782 		 * Set direction to "input" iff pin is open-drain and reset
1783 		 * value is 1.
1784 		 */
1785 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1786 			priv->gpio_input |= BIT(i);
1787 	}
1788 
1789 	return 0;
1790 }
1791 
1792 static int cp2108_gpio_init(struct usb_serial *serial)
1793 {
1794 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1795 	struct cp210x_quad_port_config config;
1796 	u16 gpio_latch;
1797 	int result;
1798 	u8 i;
1799 
1800 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1801 					  CP210X_GET_PORTCONFIG, &config,
1802 					  sizeof(config));
1803 	if (result < 0)
1804 		return result;
1805 
1806 	priv->gc.ngpio = 16;
1807 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1808 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1809 
1810 	/*
1811 	 * Mark all pins which are not in GPIO mode.
1812 	 *
1813 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1814 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1815 	 *
1816 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1817 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1818 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1819 	 */
1820 	for (i = 0; i < 4; i++) {
1821 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1822 			priv->gpio_altfunc |= BIT(i * 4);
1823 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1824 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1825 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1826 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1827 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1828 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1829 	}
1830 
1831 	/*
1832 	 * Like CP2102N, CP2108 has also no strict input and output pin
1833 	 * modes. Do the same input mode emulation as CP2102N.
1834 	 */
1835 	for (i = 0; i < priv->gc.ngpio; ++i) {
1836 		/*
1837 		 * Set direction to "input" iff pin is open-drain and reset
1838 		 * value is 1.
1839 		 */
1840 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1841 			priv->gpio_input |= BIT(i);
1842 	}
1843 
1844 	return 0;
1845 }
1846 
1847 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1848 {
1849 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1850 	const u16 config_size = 0x02a6;
1851 	u8 gpio_rst_latch;
1852 	u8 config_version;
1853 	u8 gpio_pushpull;
1854 	u8 *config_buf;
1855 	u8 gpio_latch;
1856 	u8 gpio_ctrl;
1857 	int result;
1858 	u8 i;
1859 
1860 	/*
1861 	 * Retrieve device configuration from the device.
1862 	 * The array received contains all customization settings done at the
1863 	 * factory/manufacturer. Format of the array is documented at the
1864 	 * time of writing at:
1865 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1866 	 */
1867 	config_buf = kmalloc(config_size, GFP_KERNEL);
1868 	if (!config_buf)
1869 		return -ENOMEM;
1870 
1871 	result = cp210x_read_vendor_block(serial,
1872 					  REQTYPE_DEVICE_TO_HOST,
1873 					  CP210X_READ_2NCONFIG,
1874 					  config_buf,
1875 					  config_size);
1876 	if (result < 0) {
1877 		kfree(config_buf);
1878 		return result;
1879 	}
1880 
1881 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1882 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1883 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1884 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1885 
1886 	kfree(config_buf);
1887 
1888 	/* Make sure this is a config format we understand. */
1889 	if (config_version != 0x01)
1890 		return -ENOTSUPP;
1891 
1892 	priv->gc.ngpio = 4;
1893 
1894 	/*
1895 	 * Get default pin states after reset. Needed so we can determine
1896 	 * the direction of an open-drain pin.
1897 	 */
1898 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1899 
1900 	/* 0 indicates open-drain mode, 1 is push-pull */
1901 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1902 
1903 	/* 0 indicates GPIO mode, 1 is alternate function */
1904 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1905 		/* QFN20 is special... */
1906 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1907 			priv->gpio_altfunc |= BIT(0);
1908 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1909 			priv->gpio_altfunc |= BIT(1);
1910 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1911 			priv->gpio_altfunc |= BIT(2);
1912 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1913 			priv->gpio_altfunc |= BIT(3);
1914 	} else {
1915 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1916 	}
1917 
1918 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1919 		/*
1920 		 * For the QFN28 package, GPIO4-6 are controlled by
1921 		 * the low three bits of the mode/latch fields.
1922 		 * Contrary to the document linked above, the bits for
1923 		 * the SUSPEND pins are elsewhere.  No alternate
1924 		 * function is available for these pins.
1925 		 */
1926 		priv->gc.ngpio = 7;
1927 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1928 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1929 	}
1930 
1931 	/*
1932 	 * The CP2102N does not strictly has input and output pin modes,
1933 	 * it only knows open-drain and push-pull modes which is set at
1934 	 * factory. An open-drain pin can function both as an
1935 	 * input or an output. We emulate input mode for open-drain pins
1936 	 * by making sure they are not driven low, and we do not allow
1937 	 * push-pull pins to be set as an input.
1938 	 */
1939 	for (i = 0; i < priv->gc.ngpio; ++i) {
1940 		/*
1941 		 * Set direction to "input" iff pin is open-drain and reset
1942 		 * value is 1.
1943 		 */
1944 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1945 			priv->gpio_input |= BIT(i);
1946 	}
1947 
1948 	return 0;
1949 }
1950 
1951 static int cp210x_gpio_init(struct usb_serial *serial)
1952 {
1953 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1954 	int result;
1955 
1956 	switch (priv->partnum) {
1957 	case CP210X_PARTNUM_CP2104:
1958 		result = cp2104_gpioconf_init(serial);
1959 		break;
1960 	case CP210X_PARTNUM_CP2105:
1961 		result = cp2105_gpioconf_init(serial);
1962 		break;
1963 	case CP210X_PARTNUM_CP2108:
1964 		/*
1965 		 * The GPIOs are not tied to any specific port so only register
1966 		 * once for interface 0.
1967 		 */
1968 		if (cp210x_interface_num(serial) != 0)
1969 			return 0;
1970 		result = cp2108_gpio_init(serial);
1971 		break;
1972 	case CP210X_PARTNUM_CP2102N_QFN28:
1973 	case CP210X_PARTNUM_CP2102N_QFN24:
1974 	case CP210X_PARTNUM_CP2102N_QFN20:
1975 		result = cp2102n_gpioconf_init(serial);
1976 		break;
1977 	default:
1978 		return 0;
1979 	}
1980 
1981 	if (result < 0)
1982 		return result;
1983 
1984 	priv->gc.label = "cp210x";
1985 	priv->gc.get_direction = cp210x_gpio_direction_get;
1986 	priv->gc.direction_input = cp210x_gpio_direction_input;
1987 	priv->gc.direction_output = cp210x_gpio_direction_output;
1988 	priv->gc.get = cp210x_gpio_get;
1989 	priv->gc.set = cp210x_gpio_set;
1990 	priv->gc.set_config = cp210x_gpio_set_config;
1991 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1992 	priv->gc.owner = THIS_MODULE;
1993 	priv->gc.parent = &serial->interface->dev;
1994 	priv->gc.base = -1;
1995 	priv->gc.can_sleep = true;
1996 
1997 	result = gpiochip_add_data(&priv->gc, serial);
1998 	if (!result)
1999 		priv->gpio_registered = true;
2000 
2001 	return result;
2002 }
2003 
2004 static void cp210x_gpio_remove(struct usb_serial *serial)
2005 {
2006 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2007 
2008 	if (priv->gpio_registered) {
2009 		gpiochip_remove(&priv->gc);
2010 		priv->gpio_registered = false;
2011 	}
2012 }
2013 
2014 #else
2015 
2016 static int cp210x_gpio_init(struct usb_serial *serial)
2017 {
2018 	return 0;
2019 }
2020 
2021 static void cp210x_gpio_remove(struct usb_serial *serial)
2022 {
2023 	/* Nothing to do */
2024 }
2025 
2026 #endif
2027 
2028 static int cp210x_port_probe(struct usb_serial_port *port)
2029 {
2030 	struct usb_serial *serial = port->serial;
2031 	struct cp210x_port_private *port_priv;
2032 
2033 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
2034 	if (!port_priv)
2035 		return -ENOMEM;
2036 
2037 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
2038 	mutex_init(&port_priv->mutex);
2039 
2040 	usb_set_serial_port_data(port, port_priv);
2041 
2042 	return 0;
2043 }
2044 
2045 static void cp210x_port_remove(struct usb_serial_port *port)
2046 {
2047 	struct cp210x_port_private *port_priv;
2048 
2049 	port_priv = usb_get_serial_port_data(port);
2050 	kfree(port_priv);
2051 }
2052 
2053 static void cp210x_init_max_speed(struct usb_serial *serial)
2054 {
2055 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2056 	bool use_actual_rate = false;
2057 	speed_t min = 300;
2058 	speed_t max;
2059 
2060 	switch (priv->partnum) {
2061 	case CP210X_PARTNUM_CP2101:
2062 		max = 921600;
2063 		break;
2064 	case CP210X_PARTNUM_CP2102:
2065 	case CP210X_PARTNUM_CP2103:
2066 		max = 1000000;
2067 		break;
2068 	case CP210X_PARTNUM_CP2104:
2069 		use_actual_rate = true;
2070 		max = 2000000;
2071 		break;
2072 	case CP210X_PARTNUM_CP2108:
2073 		max = 2000000;
2074 		break;
2075 	case CP210X_PARTNUM_CP2105:
2076 		if (cp210x_interface_num(serial) == 0) {
2077 			use_actual_rate = true;
2078 			max = 2000000;	/* ECI */
2079 		} else {
2080 			min = 2400;
2081 			max = 921600;	/* SCI */
2082 		}
2083 		break;
2084 	case CP210X_PARTNUM_CP2102N_QFN28:
2085 	case CP210X_PARTNUM_CP2102N_QFN24:
2086 	case CP210X_PARTNUM_CP2102N_QFN20:
2087 		use_actual_rate = true;
2088 		max = 3000000;
2089 		break;
2090 	default:
2091 		max = 2000000;
2092 		break;
2093 	}
2094 
2095 	priv->min_speed = min;
2096 	priv->max_speed = max;
2097 	priv->use_actual_rate = use_actual_rate;
2098 }
2099 
2100 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2101 {
2102 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2103 	u8 ver[3];
2104 	int ret;
2105 
2106 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2107 			ver, sizeof(ver));
2108 	if (ret)
2109 		return ret;
2110 
2111 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2112 			ver[0], ver[1], ver[2]);
2113 
2114 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2115 
2116 	return 0;
2117 }
2118 
2119 static void cp210x_determine_quirks(struct usb_serial *serial)
2120 {
2121 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2122 	int ret;
2123 
2124 	switch (priv->partnum) {
2125 	case CP210X_PARTNUM_CP2102N_QFN28:
2126 	case CP210X_PARTNUM_CP2102N_QFN24:
2127 	case CP210X_PARTNUM_CP2102N_QFN20:
2128 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2129 		if (ret)
2130 			break;
2131 		if (priv->fw_version <= 0x10004)
2132 			priv->no_flow_control = true;
2133 		break;
2134 	default:
2135 		break;
2136 	}
2137 }
2138 
2139 static int cp210x_attach(struct usb_serial *serial)
2140 {
2141 	int result;
2142 	struct cp210x_serial_private *priv;
2143 
2144 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2145 	if (!priv)
2146 		return -ENOMEM;
2147 
2148 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2149 					  CP210X_GET_PARTNUM, &priv->partnum,
2150 					  sizeof(priv->partnum));
2151 	if (result < 0) {
2152 		dev_warn(&serial->interface->dev,
2153 			 "querying part number failed\n");
2154 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2155 	}
2156 
2157 	usb_set_serial_data(serial, priv);
2158 
2159 	cp210x_determine_quirks(serial);
2160 	cp210x_init_max_speed(serial);
2161 
2162 	result = cp210x_gpio_init(serial);
2163 	if (result < 0) {
2164 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2165 				result);
2166 	}
2167 
2168 	return 0;
2169 }
2170 
2171 static void cp210x_disconnect(struct usb_serial *serial)
2172 {
2173 	cp210x_gpio_remove(serial);
2174 }
2175 
2176 static void cp210x_release(struct usb_serial *serial)
2177 {
2178 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2179 
2180 	cp210x_gpio_remove(serial);
2181 
2182 	kfree(priv);
2183 }
2184 
2185 module_usb_serial_driver(serial_drivers, id_table);
2186 
2187 MODULE_DESCRIPTION(DRIVER_DESC);
2188 MODULE_LICENSE("GPL v2");
2189