xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision b50f8f09c622297d3cf46e332e17ba8adedec9af)
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(0x0404, 0x034C) },	/* NCR Retail IO Box */
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, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
150 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
151 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
152 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
153 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
154 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
155 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
156 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
157 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
158 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
159 	{ USB_DEVICE(0x10C4, 0x8A5B) }, /* CEL EM3588 ZigBee USB Stick */
160 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
161 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
162 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
163 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
164 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
165 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
166 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
167 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
168 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
169 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
170 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
171 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
172 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
173 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
174 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
175 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
176 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
177 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
178 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
179 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
180 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
181 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
182 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
183 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
184 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
185 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
186 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
187 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
188 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
189 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
190 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
191 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
192 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
193 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
194 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
195 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
196 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
197 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
198 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
199 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
200 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
201 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
202 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
203 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
204 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
205 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
206 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
207 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 M.2 Key E serial interface */
208 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 Display serial interface */
209 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
210 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
211 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
212 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
213 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
214 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
215 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
216 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
217 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
218 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
219 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
220 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
221 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
222 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
223 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
224 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
225 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
226 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
227 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
228 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
229 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
230 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
231 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
232 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
233 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
234 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
235 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
236 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
237 	{ USB_DEVICE(0x2184, 0x0030) }, /* GW Instek GDM-834x Digital Multimeter */
238 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
239 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
240 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
241 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
242 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
243 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
244 	{ } /* Terminating Entry */
245 };
246 
247 MODULE_DEVICE_TABLE(usb, id_table);
248 
249 struct cp210x_serial_private {
250 #ifdef CONFIG_GPIOLIB
251 	struct gpio_chip	gc;
252 	bool			gpio_registered;
253 	u16			gpio_pushpull;
254 	u16			gpio_altfunc;
255 	u16			gpio_input;
256 #endif
257 	u8			partnum;
258 	u32			fw_version;
259 	speed_t			min_speed;
260 	speed_t			max_speed;
261 	bool			use_actual_rate;
262 	bool			no_flow_control;
263 	bool			no_event_mode;
264 };
265 
266 enum cp210x_event_state {
267 	ES_DATA,
268 	ES_ESCAPE,
269 	ES_LSR,
270 	ES_LSR_DATA_0,
271 	ES_LSR_DATA_1,
272 	ES_MSR
273 };
274 
275 struct cp210x_port_private {
276 	u8			bInterfaceNumber;
277 	bool			event_mode;
278 	enum cp210x_event_state event_state;
279 	u8			lsr;
280 
281 	struct mutex		mutex;
282 	bool			crtscts;
283 	bool			dtr;
284 	bool			rts;
285 };
286 
287 static struct usb_serial_driver cp210x_device = {
288 	.driver = {
289 		.owner =	THIS_MODULE,
290 		.name =		"cp210x",
291 	},
292 	.id_table		= id_table,
293 	.num_ports		= 1,
294 	.bulk_in_size		= 256,
295 	.bulk_out_size		= 256,
296 	.open			= cp210x_open,
297 	.close			= cp210x_close,
298 	.break_ctl		= cp210x_break_ctl,
299 	.set_termios		= cp210x_set_termios,
300 	.tx_empty		= cp210x_tx_empty,
301 	.throttle		= usb_serial_generic_throttle,
302 	.unthrottle		= usb_serial_generic_unthrottle,
303 	.tiocmget		= cp210x_tiocmget,
304 	.tiocmset		= cp210x_tiocmset,
305 	.get_icount		= usb_serial_generic_get_icount,
306 	.attach			= cp210x_attach,
307 	.disconnect		= cp210x_disconnect,
308 	.release		= cp210x_release,
309 	.port_probe		= cp210x_port_probe,
310 	.port_remove		= cp210x_port_remove,
311 	.dtr_rts		= cp210x_dtr_rts,
312 	.process_read_urb	= cp210x_process_read_urb,
313 };
314 
315 static struct usb_serial_driver * const serial_drivers[] = {
316 	&cp210x_device, NULL
317 };
318 
319 /* Config request types */
320 #define REQTYPE_HOST_TO_INTERFACE	0x41
321 #define REQTYPE_INTERFACE_TO_HOST	0xc1
322 #define REQTYPE_HOST_TO_DEVICE	0x40
323 #define REQTYPE_DEVICE_TO_HOST	0xc0
324 
325 /* Config request codes */
326 #define CP210X_IFC_ENABLE	0x00
327 #define CP210X_SET_BAUDDIV	0x01
328 #define CP210X_GET_BAUDDIV	0x02
329 #define CP210X_SET_LINE_CTL	0x03
330 #define CP210X_GET_LINE_CTL	0x04
331 #define CP210X_SET_BREAK	0x05
332 #define CP210X_IMM_CHAR		0x06
333 #define CP210X_SET_MHS		0x07
334 #define CP210X_GET_MDMSTS	0x08
335 #define CP210X_SET_XON		0x09
336 #define CP210X_SET_XOFF		0x0A
337 #define CP210X_SET_EVENTMASK	0x0B
338 #define CP210X_GET_EVENTMASK	0x0C
339 #define CP210X_SET_CHAR		0x0D
340 #define CP210X_GET_CHARS	0x0E
341 #define CP210X_GET_PROPS	0x0F
342 #define CP210X_GET_COMM_STATUS	0x10
343 #define CP210X_RESET		0x11
344 #define CP210X_PURGE		0x12
345 #define CP210X_SET_FLOW		0x13
346 #define CP210X_GET_FLOW		0x14
347 #define CP210X_EMBED_EVENTS	0x15
348 #define CP210X_GET_EVENTSTATE	0x16
349 #define CP210X_SET_CHARS	0x19
350 #define CP210X_GET_BAUDRATE	0x1D
351 #define CP210X_SET_BAUDRATE	0x1E
352 #define CP210X_VENDOR_SPECIFIC	0xFF
353 
354 /* CP210X_IFC_ENABLE */
355 #define UART_ENABLE		0x0001
356 #define UART_DISABLE		0x0000
357 
358 /* CP210X_(SET|GET)_BAUDDIV */
359 #define BAUD_RATE_GEN_FREQ	0x384000
360 
361 /* CP210X_(SET|GET)_LINE_CTL */
362 #define BITS_DATA_MASK		0X0f00
363 #define BITS_DATA_5		0X0500
364 #define BITS_DATA_6		0X0600
365 #define BITS_DATA_7		0X0700
366 #define BITS_DATA_8		0X0800
367 #define BITS_DATA_9		0X0900
368 
369 #define BITS_PARITY_MASK	0x00f0
370 #define BITS_PARITY_NONE	0x0000
371 #define BITS_PARITY_ODD		0x0010
372 #define BITS_PARITY_EVEN	0x0020
373 #define BITS_PARITY_MARK	0x0030
374 #define BITS_PARITY_SPACE	0x0040
375 
376 #define BITS_STOP_MASK		0x000f
377 #define BITS_STOP_1		0x0000
378 #define BITS_STOP_1_5		0x0001
379 #define BITS_STOP_2		0x0002
380 
381 /* CP210X_SET_BREAK */
382 #define BREAK_ON		0x0001
383 #define BREAK_OFF		0x0000
384 
385 /* CP210X_(SET_MHS|GET_MDMSTS) */
386 #define CONTROL_DTR		0x0001
387 #define CONTROL_RTS		0x0002
388 #define CONTROL_CTS		0x0010
389 #define CONTROL_DSR		0x0020
390 #define CONTROL_RING		0x0040
391 #define CONTROL_DCD		0x0080
392 #define CONTROL_WRITE_DTR	0x0100
393 #define CONTROL_WRITE_RTS	0x0200
394 
395 /* CP210X_(GET|SET)_CHARS */
396 struct cp210x_special_chars {
397 	u8	bEofChar;
398 	u8	bErrorChar;
399 	u8	bBreakChar;
400 	u8	bEventChar;
401 	u8	bXonChar;
402 	u8	bXoffChar;
403 };
404 
405 /* CP210X_VENDOR_SPECIFIC values */
406 #define CP210X_GET_FW_VER	0x000E
407 #define CP210X_READ_2NCONFIG	0x000E
408 #define CP210X_GET_FW_VER_2N	0x0010
409 #define CP210X_READ_LATCH	0x00C2
410 #define CP210X_GET_PARTNUM	0x370B
411 #define CP210X_GET_PORTCONFIG	0x370C
412 #define CP210X_GET_DEVICEMODE	0x3711
413 #define CP210X_WRITE_LATCH	0x37E1
414 
415 /* Part number definitions */
416 #define CP210X_PARTNUM_CP2101	0x01
417 #define CP210X_PARTNUM_CP2102	0x02
418 #define CP210X_PARTNUM_CP2103	0x03
419 #define CP210X_PARTNUM_CP2104	0x04
420 #define CP210X_PARTNUM_CP2105	0x05
421 #define CP210X_PARTNUM_CP2108	0x08
422 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
423 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
424 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
425 #define CP210X_PARTNUM_UNKNOWN	0xFF
426 
427 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
428 struct cp210x_comm_status {
429 	__le32   ulErrors;
430 	__le32   ulHoldReasons;
431 	__le32   ulAmountInInQueue;
432 	__le32   ulAmountInOutQueue;
433 	u8       bEofReceived;
434 	u8       bWaitForImmediate;
435 	u8       bReserved;
436 } __packed;
437 
438 /*
439  * CP210X_PURGE - 16 bits passed in wValue of USB request.
440  * SiLabs app note AN571 gives a strange description of the 4 bits:
441  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
442  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
443  */
444 #define PURGE_ALL		0x000f
445 
446 /* CP210X_EMBED_EVENTS */
447 #define CP210X_ESCCHAR		0xec
448 
449 #define CP210X_LSR_OVERRUN	BIT(1)
450 #define CP210X_LSR_PARITY	BIT(2)
451 #define CP210X_LSR_FRAME	BIT(3)
452 #define CP210X_LSR_BREAK	BIT(4)
453 
454 
455 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
456 struct cp210x_flow_ctl {
457 	__le32	ulControlHandshake;
458 	__le32	ulFlowReplace;
459 	__le32	ulXonLimit;
460 	__le32	ulXoffLimit;
461 };
462 
463 /* cp210x_flow_ctl::ulControlHandshake */
464 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
465 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
466 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
467 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
468 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
469 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
470 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
471 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
472 
473 /* cp210x_flow_ctl::ulFlowReplace */
474 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
475 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
476 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
477 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
478 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
479 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
480 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
481 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
482 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
483 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
484 
485 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
486 struct cp210x_pin_mode {
487 	u8	eci;
488 	u8	sci;
489 };
490 
491 #define CP210X_PIN_MODE_MODEM		0
492 #define CP210X_PIN_MODE_GPIO		BIT(0)
493 
494 /*
495  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
496  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
497  */
498 struct cp210x_dual_port_config {
499 	__le16	gpio_mode;
500 	u8	__pad0[2];
501 	__le16	reset_state;
502 	u8	__pad1[4];
503 	__le16	suspend_state;
504 	u8	sci_cfg;
505 	u8	eci_cfg;
506 	u8	device_cfg;
507 } __packed;
508 
509 /*
510  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
511  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
512  */
513 struct cp210x_single_port_config {
514 	__le16	gpio_mode;
515 	u8	__pad0[2];
516 	__le16	reset_state;
517 	u8	__pad1[4];
518 	__le16	suspend_state;
519 	u8	device_cfg;
520 } __packed;
521 
522 /* GPIO modes */
523 #define CP210X_SCI_GPIO_MODE_OFFSET	9
524 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
525 
526 #define CP210X_ECI_GPIO_MODE_OFFSET	2
527 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
528 
529 #define CP210X_GPIO_MODE_OFFSET		8
530 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
531 
532 /* CP2105 port configuration values */
533 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
534 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
535 #define CP2105_GPIO1_RS485_MODE		BIT(2)
536 
537 /* CP2104 port configuration values */
538 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
539 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
540 #define CP2104_GPIO2_RS485_MODE		BIT(2)
541 
542 struct cp210x_quad_port_state {
543 	__le16 gpio_mode_pb0;
544 	__le16 gpio_mode_pb1;
545 	__le16 gpio_mode_pb2;
546 	__le16 gpio_mode_pb3;
547 	__le16 gpio_mode_pb4;
548 
549 	__le16 gpio_lowpower_pb0;
550 	__le16 gpio_lowpower_pb1;
551 	__le16 gpio_lowpower_pb2;
552 	__le16 gpio_lowpower_pb3;
553 	__le16 gpio_lowpower_pb4;
554 
555 	__le16 gpio_latch_pb0;
556 	__le16 gpio_latch_pb1;
557 	__le16 gpio_latch_pb2;
558 	__le16 gpio_latch_pb3;
559 	__le16 gpio_latch_pb4;
560 };
561 
562 /*
563  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
564  * on a CP2108 chip.
565  *
566  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
567  */
568 struct cp210x_quad_port_config {
569 	struct cp210x_quad_port_state reset_state;
570 	struct cp210x_quad_port_state suspend_state;
571 	u8 ipdelay_ifc[4];
572 	u8 enhancedfxn_ifc[4];
573 	u8 enhancedfxn_device;
574 	u8 extclkfreq[4];
575 } __packed;
576 
577 #define CP2108_EF_IFC_GPIO_TXLED		0x01
578 #define CP2108_EF_IFC_GPIO_RXLED		0x02
579 #define CP2108_EF_IFC_GPIO_RS485		0x04
580 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
581 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
582 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
583 
584 /* CP2102N configuration array indices */
585 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
586 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
587 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
588 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
589 
590 /* CP2102N QFN20 port configuration values */
591 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
592 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
593 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
594 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
595 
596 /*
597  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
598  * for CP2102N, CP2103, CP2104 and CP2105.
599  */
600 struct cp210x_gpio_write {
601 	u8	mask;
602 	u8	state;
603 };
604 
605 /*
606  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
607  * for CP2108.
608  */
609 struct cp210x_gpio_write16 {
610 	__le16	mask;
611 	__le16	state;
612 };
613 
614 /*
615  * Helper to get interface number when we only have struct usb_serial.
616  */
617 static u8 cp210x_interface_num(struct usb_serial *serial)
618 {
619 	struct usb_host_interface *cur_altsetting;
620 
621 	cur_altsetting = serial->interface->cur_altsetting;
622 
623 	return cur_altsetting->desc.bInterfaceNumber;
624 }
625 
626 /*
627  * Reads a variable-sized block of CP210X_ registers, identified by req.
628  * Returns data into buf in native USB byte order.
629  */
630 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
631 		void *buf, int bufsize)
632 {
633 	struct usb_serial *serial = port->serial;
634 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
635 	int result;
636 
637 
638 	result = usb_control_msg_recv(serial->dev, 0, req,
639 			REQTYPE_INTERFACE_TO_HOST, 0,
640 			port_priv->bInterfaceNumber, buf, bufsize,
641 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
642 	if (result) {
643 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
644 				req, bufsize, result);
645 		return result;
646 	}
647 
648 	return 0;
649 }
650 
651 /*
652  * Reads any 8-bit CP210X_ register identified by req.
653  */
654 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
655 {
656 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
657 }
658 
659 /*
660  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
661  * Returns data into buf in native USB byte order.
662  */
663 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
664 				    void *buf, int bufsize)
665 {
666 	int result;
667 
668 	result = usb_control_msg_recv(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
669 			type, val, cp210x_interface_num(serial), buf, bufsize,
670 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
671 	if (result) {
672 		dev_err(&serial->interface->dev,
673 			"failed to get vendor val 0x%04x size %d: %d\n", val,
674 			bufsize, result);
675 		return result;
676 	}
677 
678 	return 0;
679 }
680 
681 /*
682  * Writes any 16-bit CP210X_ register (req) whose value is passed
683  * entirely in the wValue field of the USB request.
684  */
685 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
686 {
687 	struct usb_serial *serial = port->serial;
688 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
689 	int result;
690 
691 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
692 			req, REQTYPE_HOST_TO_INTERFACE, val,
693 			port_priv->bInterfaceNumber, NULL, 0,
694 			USB_CTRL_SET_TIMEOUT);
695 	if (result < 0) {
696 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
697 				req, result);
698 	}
699 
700 	return result;
701 }
702 
703 /*
704  * Writes a variable-sized block of CP210X_ registers, identified by req.
705  * Data in buf must be in native USB byte order.
706  */
707 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
708 		void *buf, int bufsize)
709 {
710 	struct usb_serial *serial = port->serial;
711 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
712 	int result;
713 
714 	result = usb_control_msg_send(serial->dev, 0, req,
715 			REQTYPE_HOST_TO_INTERFACE, 0,
716 			port_priv->bInterfaceNumber, buf, bufsize,
717 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
718 	if (result) {
719 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
720 				req, bufsize, result);
721 		return result;
722 	}
723 
724 	return 0;
725 }
726 
727 /*
728  * Writes any 32-bit CP210X_ register identified by req.
729  */
730 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
731 {
732 	__le32 le32_val;
733 
734 	le32_val = cpu_to_le32(val);
735 
736 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
737 }
738 
739 #ifdef CONFIG_GPIOLIB
740 /*
741  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
742  * Data in buf must be in native USB byte order.
743  */
744 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
745 				     u16 val, void *buf, int bufsize)
746 {
747 	int result;
748 
749 	result = usb_control_msg_send(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
750 			type, val, cp210x_interface_num(serial), buf, bufsize,
751 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
752 	if (result) {
753 		dev_err(&serial->interface->dev,
754 			"failed to set vendor val 0x%04x size %d: %d\n", val,
755 			bufsize, result);
756 		return result;
757 	}
758 
759 	return 0;
760 }
761 #endif
762 
763 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
764 {
765 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
766 	int result;
767 
768 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
769 	if (result) {
770 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
771 		return result;
772 	}
773 
774 	if (tty)
775 		cp210x_set_termios(tty, port, NULL);
776 
777 	result = usb_serial_generic_open(tty, port);
778 	if (result)
779 		goto err_disable;
780 
781 	return 0;
782 
783 err_disable:
784 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
785 	port_priv->event_mode = false;
786 
787 	return result;
788 }
789 
790 static void cp210x_close(struct usb_serial_port *port)
791 {
792 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
793 
794 	usb_serial_generic_close(port);
795 
796 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
797 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
798 
799 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
800 
801 	/* Disabling the interface disables event-insertion mode. */
802 	port_priv->event_mode = false;
803 }
804 
805 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
806 {
807 	if (lsr & CP210X_LSR_BREAK) {
808 		port->icount.brk++;
809 		*flag = TTY_BREAK;
810 	} else if (lsr & CP210X_LSR_PARITY) {
811 		port->icount.parity++;
812 		*flag = TTY_PARITY;
813 	} else if (lsr & CP210X_LSR_FRAME) {
814 		port->icount.frame++;
815 		*flag = TTY_FRAME;
816 	}
817 
818 	if (lsr & CP210X_LSR_OVERRUN) {
819 		port->icount.overrun++;
820 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
821 	}
822 }
823 
824 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
825 {
826 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
827 
828 	switch (port_priv->event_state) {
829 	case ES_DATA:
830 		if (*ch == CP210X_ESCCHAR) {
831 			port_priv->event_state = ES_ESCAPE;
832 			break;
833 		}
834 		return false;
835 	case ES_ESCAPE:
836 		switch (*ch) {
837 		case 0:
838 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
839 			*ch = CP210X_ESCCHAR;
840 			port_priv->event_state = ES_DATA;
841 			return false;
842 		case 1:
843 			port_priv->event_state = ES_LSR_DATA_0;
844 			break;
845 		case 2:
846 			port_priv->event_state = ES_LSR;
847 			break;
848 		case 3:
849 			port_priv->event_state = ES_MSR;
850 			break;
851 		default:
852 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
853 			port_priv->event_state = ES_DATA;
854 			break;
855 		}
856 		break;
857 	case ES_LSR_DATA_0:
858 		port_priv->lsr = *ch;
859 		port_priv->event_state = ES_LSR_DATA_1;
860 		break;
861 	case ES_LSR_DATA_1:
862 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
863 				__func__, port_priv->lsr, *ch);
864 		cp210x_process_lsr(port, port_priv->lsr, flag);
865 		port_priv->event_state = ES_DATA;
866 		return false;
867 	case ES_LSR:
868 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
869 		port_priv->lsr = *ch;
870 		cp210x_process_lsr(port, port_priv->lsr, flag);
871 		port_priv->event_state = ES_DATA;
872 		break;
873 	case ES_MSR:
874 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
875 		/* unimplemented */
876 		port_priv->event_state = ES_DATA;
877 		break;
878 	}
879 
880 	return true;
881 }
882 
883 static void cp210x_process_read_urb(struct urb *urb)
884 {
885 	struct usb_serial_port *port = urb->context;
886 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
887 	unsigned char *ch = urb->transfer_buffer;
888 	char flag;
889 	int i;
890 
891 	if (!urb->actual_length)
892 		return;
893 
894 	if (port_priv->event_mode) {
895 		for (i = 0; i < urb->actual_length; i++, ch++) {
896 			flag = TTY_NORMAL;
897 
898 			if (cp210x_process_char(port, ch, &flag))
899 				continue;
900 
901 			tty_insert_flip_char(&port->port, *ch, flag);
902 		}
903 	} else {
904 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
905 	}
906 	tty_flip_buffer_push(&port->port);
907 }
908 
909 /*
910  * Read how many bytes are waiting in the TX queue.
911  */
912 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
913 		u32 *count)
914 {
915 	struct usb_serial *serial = port->serial;
916 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
917 	struct cp210x_comm_status sts;
918 	int result;
919 
920 	result = usb_control_msg_recv(serial->dev, 0, CP210X_GET_COMM_STATUS,
921 			REQTYPE_INTERFACE_TO_HOST, 0,
922 			port_priv->bInterfaceNumber, &sts, sizeof(sts),
923 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
924 	if (result) {
925 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
926 		return result;
927 	}
928 
929 	*count = le32_to_cpu(sts.ulAmountInOutQueue);
930 
931 	return 0;
932 }
933 
934 static bool cp210x_tx_empty(struct usb_serial_port *port)
935 {
936 	int err;
937 	u32 count;
938 
939 	err = cp210x_get_tx_queue_byte_count(port, &count);
940 	if (err)
941 		return true;
942 
943 	return !count;
944 }
945 
946 struct cp210x_rate {
947 	speed_t rate;
948 	speed_t high;
949 };
950 
951 static const struct cp210x_rate cp210x_an205_table1[] = {
952 	{ 300, 300 },
953 	{ 600, 600 },
954 	{ 1200, 1200 },
955 	{ 1800, 1800 },
956 	{ 2400, 2400 },
957 	{ 4000, 4000 },
958 	{ 4800, 4803 },
959 	{ 7200, 7207 },
960 	{ 9600, 9612 },
961 	{ 14400, 14428 },
962 	{ 16000, 16062 },
963 	{ 19200, 19250 },
964 	{ 28800, 28912 },
965 	{ 38400, 38601 },
966 	{ 51200, 51558 },
967 	{ 56000, 56280 },
968 	{ 57600, 58053 },
969 	{ 64000, 64111 },
970 	{ 76800, 77608 },
971 	{ 115200, 117028 },
972 	{ 128000, 129347 },
973 	{ 153600, 156868 },
974 	{ 230400, 237832 },
975 	{ 250000, 254234 },
976 	{ 256000, 273066 },
977 	{ 460800, 491520 },
978 	{ 500000, 567138 },
979 	{ 576000, 670254 },
980 	{ 921600, UINT_MAX }
981 };
982 
983 /*
984  * Quantises the baud rate as per AN205 Table 1
985  */
986 static speed_t cp210x_get_an205_rate(speed_t baud)
987 {
988 	int i;
989 
990 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
991 		if (baud <= cp210x_an205_table1[i].high)
992 			break;
993 	}
994 
995 	return cp210x_an205_table1[i].rate;
996 }
997 
998 static speed_t cp210x_get_actual_rate(speed_t baud)
999 {
1000 	unsigned int prescale = 1;
1001 	unsigned int div;
1002 
1003 	if (baud <= 365)
1004 		prescale = 4;
1005 
1006 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1007 	baud = 48000000 / (2 * prescale * div);
1008 
1009 	return baud;
1010 }
1011 
1012 /*
1013  * CP2101 supports the following baud rates:
1014  *
1015  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1016  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1017  *
1018  * CP2102 and CP2103 support the following additional rates:
1019  *
1020  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1021  *	576000
1022  *
1023  * The device will map a requested rate to a supported one, but the result
1024  * of requests for rates greater than 1053257 is undefined (see AN205).
1025  *
1026  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1027  * respectively, with an error less than 1%. The actual rates are determined
1028  * by
1029  *
1030  *	div = round(freq / (2 x prescale x request))
1031  *	actual = freq / (2 x prescale x div)
1032  *
1033  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1034  * or 1 otherwise.
1035  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1036  * otherwise.
1037  */
1038 static void cp210x_change_speed(struct tty_struct *tty,
1039 		struct usb_serial_port *port, struct ktermios *old_termios)
1040 {
1041 	struct usb_serial *serial = port->serial;
1042 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1043 	u32 baud;
1044 
1045 	/*
1046 	 * This maps the requested rate to the actual rate, a valid rate on
1047 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1048 	 *
1049 	 * NOTE: B0 is not implemented.
1050 	 */
1051 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1052 
1053 	if (priv->use_actual_rate)
1054 		baud = cp210x_get_actual_rate(baud);
1055 	else if (baud < 1000000)
1056 		baud = cp210x_get_an205_rate(baud);
1057 
1058 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1059 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1060 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1061 		if (old_termios)
1062 			baud = old_termios->c_ospeed;
1063 		else
1064 			baud = 9600;
1065 	}
1066 
1067 	tty_encode_baud_rate(tty, baud, baud);
1068 }
1069 
1070 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1071 {
1072 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1073 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1074 	int ret;
1075 
1076 	if (port_priv->event_mode)
1077 		return;
1078 
1079 	if (priv->no_event_mode)
1080 		return;
1081 
1082 	port_priv->event_state = ES_DATA;
1083 	port_priv->event_mode = true;
1084 
1085 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1086 	if (ret) {
1087 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1088 		port_priv->event_mode = false;
1089 	}
1090 }
1091 
1092 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1093 {
1094 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1095 	int ret;
1096 
1097 	if (!port_priv->event_mode)
1098 		return;
1099 
1100 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1101 	if (ret) {
1102 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1103 		return;
1104 	}
1105 
1106 	port_priv->event_mode = false;
1107 }
1108 
1109 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1110 {
1111 	bool iflag_change, cc_change;
1112 
1113 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1114 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1115 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1116 
1117 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1118 }
1119 
1120 static void cp210x_set_flow_control(struct tty_struct *tty,
1121 		struct usb_serial_port *port, struct ktermios *old_termios)
1122 {
1123 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1124 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1125 	struct cp210x_special_chars chars;
1126 	struct cp210x_flow_ctl flow_ctl;
1127 	u32 flow_repl;
1128 	u32 ctl_hs;
1129 	bool crtscts;
1130 	int ret;
1131 
1132 	/*
1133 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1134 	 * CP2102N_E104). Report back that flow control is not supported.
1135 	 */
1136 	if (priv->no_flow_control) {
1137 		tty->termios.c_cflag &= ~CRTSCTS;
1138 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1139 	}
1140 
1141 	if (old_termios &&
1142 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1143 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1144 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1145 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1146 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1147 		return;
1148 	}
1149 
1150 	if (I_IXON(tty) || I_IXOFF(tty)) {
1151 		memset(&chars, 0, sizeof(chars));
1152 
1153 		chars.bXonChar = START_CHAR(tty);
1154 		chars.bXoffChar = STOP_CHAR(tty);
1155 
1156 		ret = cp210x_write_reg_block(port, CP210X_SET_CHARS, &chars,
1157 				sizeof(chars));
1158 		if (ret) {
1159 			dev_err(&port->dev, "failed to set special chars: %d\n",
1160 					ret);
1161 		}
1162 	}
1163 
1164 	mutex_lock(&port_priv->mutex);
1165 
1166 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1167 			sizeof(flow_ctl));
1168 	if (ret)
1169 		goto out_unlock;
1170 
1171 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1172 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1173 
1174 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1175 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1176 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1177 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1178 	if (port_priv->dtr)
1179 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1180 	else
1181 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1182 
1183 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1184 	if (C_CRTSCTS(tty)) {
1185 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1186 		if (port_priv->rts)
1187 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1188 		else
1189 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1190 		crtscts = true;
1191 	} else {
1192 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1193 		if (port_priv->rts)
1194 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1195 		else
1196 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1197 		crtscts = false;
1198 	}
1199 
1200 	if (I_IXOFF(tty)) {
1201 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1202 
1203 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1204 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1205 	} else {
1206 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1207 	}
1208 
1209 	if (I_IXON(tty))
1210 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1211 	else
1212 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1213 
1214 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1215 			ctl_hs, flow_repl);
1216 
1217 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1218 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1219 
1220 	ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1221 			sizeof(flow_ctl));
1222 	if (ret)
1223 		goto out_unlock;
1224 
1225 	port_priv->crtscts = crtscts;
1226 out_unlock:
1227 	mutex_unlock(&port_priv->mutex);
1228 }
1229 
1230 static void cp210x_set_termios(struct tty_struct *tty,
1231 		struct usb_serial_port *port, struct ktermios *old_termios)
1232 {
1233 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1234 	u16 bits;
1235 	int ret;
1236 
1237 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1238 		return;
1239 
1240 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1241 		cp210x_change_speed(tty, port, old_termios);
1242 
1243 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1244 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1245 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1246 		tty->termios.c_cflag |= CS8;
1247 	}
1248 
1249 	bits = 0;
1250 
1251 	switch (C_CSIZE(tty)) {
1252 	case CS5:
1253 		bits |= BITS_DATA_5;
1254 		break;
1255 	case CS6:
1256 		bits |= BITS_DATA_6;
1257 		break;
1258 	case CS7:
1259 		bits |= BITS_DATA_7;
1260 		break;
1261 	case CS8:
1262 	default:
1263 		bits |= BITS_DATA_8;
1264 		break;
1265 	}
1266 
1267 	if (C_PARENB(tty)) {
1268 		if (C_CMSPAR(tty)) {
1269 			if (C_PARODD(tty))
1270 				bits |= BITS_PARITY_MARK;
1271 			else
1272 				bits |= BITS_PARITY_SPACE;
1273 		} else {
1274 			if (C_PARODD(tty))
1275 				bits |= BITS_PARITY_ODD;
1276 			else
1277 				bits |= BITS_PARITY_EVEN;
1278 		}
1279 	}
1280 
1281 	if (C_CSTOPB(tty))
1282 		bits |= BITS_STOP_2;
1283 	else
1284 		bits |= BITS_STOP_1;
1285 
1286 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1287 	if (ret)
1288 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1289 
1290 	cp210x_set_flow_control(tty, port, old_termios);
1291 
1292 	/*
1293 	 * Enable event-insertion mode only if input parity checking is
1294 	 * enabled for now.
1295 	 */
1296 	if (I_INPCK(tty))
1297 		cp210x_enable_event_mode(port);
1298 	else
1299 		cp210x_disable_event_mode(port);
1300 }
1301 
1302 static int cp210x_tiocmset(struct tty_struct *tty,
1303 		unsigned int set, unsigned int clear)
1304 {
1305 	struct usb_serial_port *port = tty->driver_data;
1306 	return cp210x_tiocmset_port(port, set, clear);
1307 }
1308 
1309 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1310 		unsigned int set, unsigned int clear)
1311 {
1312 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1313 	struct cp210x_flow_ctl flow_ctl;
1314 	u32 ctl_hs, flow_repl;
1315 	u16 control = 0;
1316 	int ret;
1317 
1318 	mutex_lock(&port_priv->mutex);
1319 
1320 	if (set & TIOCM_RTS) {
1321 		port_priv->rts = true;
1322 		control |= CONTROL_RTS;
1323 		control |= CONTROL_WRITE_RTS;
1324 	}
1325 	if (set & TIOCM_DTR) {
1326 		port_priv->dtr = true;
1327 		control |= CONTROL_DTR;
1328 		control |= CONTROL_WRITE_DTR;
1329 	}
1330 	if (clear & TIOCM_RTS) {
1331 		port_priv->rts = false;
1332 		control &= ~CONTROL_RTS;
1333 		control |= CONTROL_WRITE_RTS;
1334 	}
1335 	if (clear & TIOCM_DTR) {
1336 		port_priv->dtr = false;
1337 		control &= ~CONTROL_DTR;
1338 		control |= CONTROL_WRITE_DTR;
1339 	}
1340 
1341 	/*
1342 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1343 	 * flow control is enabled.
1344 	 */
1345 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1346 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1347 				sizeof(flow_ctl));
1348 		if (ret)
1349 			goto out_unlock;
1350 
1351 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1352 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1353 
1354 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1355 		if (port_priv->dtr)
1356 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1357 		else
1358 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1359 
1360 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1361 		if (port_priv->rts)
1362 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1363 		else
1364 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1365 
1366 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1367 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1368 
1369 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1370 				__func__, ctl_hs, flow_repl);
1371 
1372 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1373 				sizeof(flow_ctl));
1374 	} else {
1375 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1376 
1377 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1378 	}
1379 out_unlock:
1380 	mutex_unlock(&port_priv->mutex);
1381 
1382 	return ret;
1383 }
1384 
1385 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1386 {
1387 	if (on)
1388 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1389 	else
1390 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1391 }
1392 
1393 static int cp210x_tiocmget(struct tty_struct *tty)
1394 {
1395 	struct usb_serial_port *port = tty->driver_data;
1396 	u8 control;
1397 	int result;
1398 
1399 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1400 	if (result)
1401 		return result;
1402 
1403 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1404 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1405 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1406 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1407 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1408 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1409 
1410 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1411 
1412 	return result;
1413 }
1414 
1415 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1416 {
1417 	struct usb_serial_port *port = tty->driver_data;
1418 	u16 state;
1419 
1420 	if (break_state == 0)
1421 		state = BREAK_OFF;
1422 	else
1423 		state = BREAK_ON;
1424 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1425 		state == BREAK_OFF ? "off" : "on");
1426 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1427 }
1428 
1429 #ifdef CONFIG_GPIOLIB
1430 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1431 {
1432 	struct usb_serial *serial = gpiochip_get_data(gc);
1433 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1434 	u8 req_type;
1435 	u16 mask;
1436 	int result;
1437 	int len;
1438 
1439 	result = usb_autopm_get_interface(serial->interface);
1440 	if (result)
1441 		return result;
1442 
1443 	switch (priv->partnum) {
1444 	case CP210X_PARTNUM_CP2105:
1445 		req_type = REQTYPE_INTERFACE_TO_HOST;
1446 		len = 1;
1447 		break;
1448 	case CP210X_PARTNUM_CP2108:
1449 		req_type = REQTYPE_INTERFACE_TO_HOST;
1450 		len = 2;
1451 		break;
1452 	default:
1453 		req_type = REQTYPE_DEVICE_TO_HOST;
1454 		len = 1;
1455 		break;
1456 	}
1457 
1458 	mask = 0;
1459 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1460 					  &mask, len);
1461 
1462 	usb_autopm_put_interface(serial->interface);
1463 
1464 	if (result < 0)
1465 		return result;
1466 
1467 	le16_to_cpus(&mask);
1468 
1469 	return !!(mask & BIT(gpio));
1470 }
1471 
1472 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1473 {
1474 	struct usb_serial *serial = gpiochip_get_data(gc);
1475 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1476 	struct cp210x_gpio_write16 buf16;
1477 	struct cp210x_gpio_write buf;
1478 	u16 mask, state;
1479 	u16 wIndex;
1480 	int result;
1481 
1482 	if (value == 1)
1483 		state = BIT(gpio);
1484 	else
1485 		state = 0;
1486 
1487 	mask = BIT(gpio);
1488 
1489 	result = usb_autopm_get_interface(serial->interface);
1490 	if (result)
1491 		goto out;
1492 
1493 	switch (priv->partnum) {
1494 	case CP210X_PARTNUM_CP2105:
1495 		buf.mask = (u8)mask;
1496 		buf.state = (u8)state;
1497 		result = cp210x_write_vendor_block(serial,
1498 						   REQTYPE_HOST_TO_INTERFACE,
1499 						   CP210X_WRITE_LATCH, &buf,
1500 						   sizeof(buf));
1501 		break;
1502 	case CP210X_PARTNUM_CP2108:
1503 		buf16.mask = cpu_to_le16(mask);
1504 		buf16.state = cpu_to_le16(state);
1505 		result = cp210x_write_vendor_block(serial,
1506 						   REQTYPE_HOST_TO_INTERFACE,
1507 						   CP210X_WRITE_LATCH, &buf16,
1508 						   sizeof(buf16));
1509 		break;
1510 	default:
1511 		wIndex = state << 8 | mask;
1512 		result = usb_control_msg(serial->dev,
1513 					 usb_sndctrlpipe(serial->dev, 0),
1514 					 CP210X_VENDOR_SPECIFIC,
1515 					 REQTYPE_HOST_TO_DEVICE,
1516 					 CP210X_WRITE_LATCH,
1517 					 wIndex,
1518 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1519 		break;
1520 	}
1521 
1522 	usb_autopm_put_interface(serial->interface);
1523 out:
1524 	if (result < 0) {
1525 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1526 				result);
1527 	}
1528 }
1529 
1530 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1531 {
1532 	struct usb_serial *serial = gpiochip_get_data(gc);
1533 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1534 
1535 	return priv->gpio_input & BIT(gpio);
1536 }
1537 
1538 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1539 {
1540 	struct usb_serial *serial = gpiochip_get_data(gc);
1541 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1542 
1543 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1544 		/* hardware does not support an input mode */
1545 		return -ENOTSUPP;
1546 	}
1547 
1548 	/* push-pull pins cannot be changed to be inputs */
1549 	if (priv->gpio_pushpull & BIT(gpio))
1550 		return -EINVAL;
1551 
1552 	/* make sure to release pin if it is being driven low */
1553 	cp210x_gpio_set(gc, gpio, 1);
1554 
1555 	priv->gpio_input |= BIT(gpio);
1556 
1557 	return 0;
1558 }
1559 
1560 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1561 					int value)
1562 {
1563 	struct usb_serial *serial = gpiochip_get_data(gc);
1564 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1565 
1566 	priv->gpio_input &= ~BIT(gpio);
1567 	cp210x_gpio_set(gc, gpio, value);
1568 
1569 	return 0;
1570 }
1571 
1572 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1573 				  unsigned long config)
1574 {
1575 	struct usb_serial *serial = gpiochip_get_data(gc);
1576 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1577 	enum pin_config_param param = pinconf_to_config_param(config);
1578 
1579 	/* Succeed only if in correct mode (this can't be set at runtime) */
1580 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1581 	    (priv->gpio_pushpull & BIT(gpio)))
1582 		return 0;
1583 
1584 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1585 	    !(priv->gpio_pushpull & BIT(gpio)))
1586 		return 0;
1587 
1588 	return -ENOTSUPP;
1589 }
1590 
1591 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1592 		unsigned long *valid_mask, unsigned int ngpios)
1593 {
1594 	struct usb_serial *serial = gpiochip_get_data(gc);
1595 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1596 	struct device *dev = &serial->interface->dev;
1597 	unsigned long altfunc_mask = priv->gpio_altfunc;
1598 
1599 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1600 
1601 	if (bitmap_empty(valid_mask, ngpios))
1602 		dev_dbg(dev, "no pin configured for GPIO\n");
1603 	else
1604 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1605 				valid_mask);
1606 	return 0;
1607 }
1608 
1609 /*
1610  * This function is for configuring GPIO using shared pins, where other signals
1611  * are made unavailable by configuring the use of GPIO. This is believed to be
1612  * only applicable to the cp2105 at this point, the other devices supported by
1613  * this driver that provide GPIO do so in a way that does not impact other
1614  * signals and are thus expected to have very different initialisation.
1615  */
1616 static int cp2105_gpioconf_init(struct usb_serial *serial)
1617 {
1618 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1619 	struct cp210x_pin_mode mode;
1620 	struct cp210x_dual_port_config config;
1621 	u8 intf_num = cp210x_interface_num(serial);
1622 	u8 iface_config;
1623 	int result;
1624 
1625 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1626 					  CP210X_GET_DEVICEMODE, &mode,
1627 					  sizeof(mode));
1628 	if (result < 0)
1629 		return result;
1630 
1631 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1632 					  CP210X_GET_PORTCONFIG, &config,
1633 					  sizeof(config));
1634 	if (result < 0)
1635 		return result;
1636 
1637 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1638 	if (intf_num == 0) {
1639 		priv->gc.ngpio = 2;
1640 
1641 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1642 			/* mark all GPIOs of this interface as reserved */
1643 			priv->gpio_altfunc = 0xff;
1644 			return 0;
1645 		}
1646 
1647 		iface_config = config.eci_cfg;
1648 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1649 						CP210X_ECI_GPIO_MODE_MASK) >>
1650 						CP210X_ECI_GPIO_MODE_OFFSET);
1651 	} else if (intf_num == 1) {
1652 		priv->gc.ngpio = 3;
1653 
1654 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1655 			/* mark all GPIOs of this interface as reserved */
1656 			priv->gpio_altfunc = 0xff;
1657 			return 0;
1658 		}
1659 
1660 		iface_config = config.sci_cfg;
1661 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1662 						CP210X_SCI_GPIO_MODE_MASK) >>
1663 						CP210X_SCI_GPIO_MODE_OFFSET);
1664 	} else {
1665 		return -ENODEV;
1666 	}
1667 
1668 	/* mark all pins which are not in GPIO mode */
1669 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1670 		priv->gpio_altfunc |= BIT(0);
1671 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1672 			CP2105_GPIO1_RS485_MODE))
1673 		priv->gpio_altfunc |= BIT(1);
1674 
1675 	/* driver implementation for CP2105 only supports outputs */
1676 	priv->gpio_input = 0;
1677 
1678 	return 0;
1679 }
1680 
1681 static int cp2104_gpioconf_init(struct usb_serial *serial)
1682 {
1683 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1684 	struct cp210x_single_port_config config;
1685 	u8 iface_config;
1686 	u8 gpio_latch;
1687 	int result;
1688 	u8 i;
1689 
1690 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1691 					  CP210X_GET_PORTCONFIG, &config,
1692 					  sizeof(config));
1693 	if (result < 0)
1694 		return result;
1695 
1696 	priv->gc.ngpio = 4;
1697 
1698 	iface_config = config.device_cfg;
1699 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1700 					CP210X_GPIO_MODE_MASK) >>
1701 					CP210X_GPIO_MODE_OFFSET);
1702 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1703 					CP210X_GPIO_MODE_MASK) >>
1704 					CP210X_GPIO_MODE_OFFSET);
1705 
1706 	/* mark all pins which are not in GPIO mode */
1707 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1708 		priv->gpio_altfunc |= BIT(0);
1709 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1710 		priv->gpio_altfunc |= BIT(1);
1711 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1712 		priv->gpio_altfunc |= BIT(2);
1713 
1714 	/*
1715 	 * Like CP2102N, CP2104 has also no strict input and output pin
1716 	 * modes.
1717 	 * Do the same input mode emulation as CP2102N.
1718 	 */
1719 	for (i = 0; i < priv->gc.ngpio; ++i) {
1720 		/*
1721 		 * Set direction to "input" iff pin is open-drain and reset
1722 		 * value is 1.
1723 		 */
1724 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1725 			priv->gpio_input |= BIT(i);
1726 	}
1727 
1728 	return 0;
1729 }
1730 
1731 static int cp2108_gpio_init(struct usb_serial *serial)
1732 {
1733 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1734 	struct cp210x_quad_port_config config;
1735 	u16 gpio_latch;
1736 	int result;
1737 	u8 i;
1738 
1739 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1740 					  CP210X_GET_PORTCONFIG, &config,
1741 					  sizeof(config));
1742 	if (result < 0)
1743 		return result;
1744 
1745 	priv->gc.ngpio = 16;
1746 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1747 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1748 
1749 	/*
1750 	 * Mark all pins which are not in GPIO mode.
1751 	 *
1752 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1753 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1754 	 *
1755 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1756 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1757 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1758 	 */
1759 	for (i = 0; i < 4; i++) {
1760 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1761 			priv->gpio_altfunc |= BIT(i * 4);
1762 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1763 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1764 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1765 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1766 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1767 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1768 	}
1769 
1770 	/*
1771 	 * Like CP2102N, CP2108 has also no strict input and output pin
1772 	 * modes. Do the same input mode emulation as CP2102N.
1773 	 */
1774 	for (i = 0; i < priv->gc.ngpio; ++i) {
1775 		/*
1776 		 * Set direction to "input" iff pin is open-drain and reset
1777 		 * value is 1.
1778 		 */
1779 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1780 			priv->gpio_input |= BIT(i);
1781 	}
1782 
1783 	return 0;
1784 }
1785 
1786 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1787 {
1788 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1789 	const u16 config_size = 0x02a6;
1790 	u8 gpio_rst_latch;
1791 	u8 config_version;
1792 	u8 gpio_pushpull;
1793 	u8 *config_buf;
1794 	u8 gpio_latch;
1795 	u8 gpio_ctrl;
1796 	int result;
1797 	u8 i;
1798 
1799 	/*
1800 	 * Retrieve device configuration from the device.
1801 	 * The array received contains all customization settings done at the
1802 	 * factory/manufacturer. Format of the array is documented at the
1803 	 * time of writing at:
1804 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1805 	 */
1806 	config_buf = kmalloc(config_size, GFP_KERNEL);
1807 	if (!config_buf)
1808 		return -ENOMEM;
1809 
1810 	result = cp210x_read_vendor_block(serial,
1811 					  REQTYPE_DEVICE_TO_HOST,
1812 					  CP210X_READ_2NCONFIG,
1813 					  config_buf,
1814 					  config_size);
1815 	if (result < 0) {
1816 		kfree(config_buf);
1817 		return result;
1818 	}
1819 
1820 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1821 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1822 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1823 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1824 
1825 	kfree(config_buf);
1826 
1827 	/* Make sure this is a config format we understand. */
1828 	if (config_version != 0x01)
1829 		return -ENOTSUPP;
1830 
1831 	priv->gc.ngpio = 4;
1832 
1833 	/*
1834 	 * Get default pin states after reset. Needed so we can determine
1835 	 * the direction of an open-drain pin.
1836 	 */
1837 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1838 
1839 	/* 0 indicates open-drain mode, 1 is push-pull */
1840 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1841 
1842 	/* 0 indicates GPIO mode, 1 is alternate function */
1843 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1844 		/* QFN20 is special... */
1845 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1846 			priv->gpio_altfunc |= BIT(0);
1847 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1848 			priv->gpio_altfunc |= BIT(1);
1849 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1850 			priv->gpio_altfunc |= BIT(2);
1851 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1852 			priv->gpio_altfunc |= BIT(3);
1853 	} else {
1854 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1855 	}
1856 
1857 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1858 		/*
1859 		 * For the QFN28 package, GPIO4-6 are controlled by
1860 		 * the low three bits of the mode/latch fields.
1861 		 * Contrary to the document linked above, the bits for
1862 		 * the SUSPEND pins are elsewhere.  No alternate
1863 		 * function is available for these pins.
1864 		 */
1865 		priv->gc.ngpio = 7;
1866 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1867 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1868 	}
1869 
1870 	/*
1871 	 * The CP2102N does not strictly has input and output pin modes,
1872 	 * it only knows open-drain and push-pull modes which is set at
1873 	 * factory. An open-drain pin can function both as an
1874 	 * input or an output. We emulate input mode for open-drain pins
1875 	 * by making sure they are not driven low, and we do not allow
1876 	 * push-pull pins to be set as an input.
1877 	 */
1878 	for (i = 0; i < priv->gc.ngpio; ++i) {
1879 		/*
1880 		 * Set direction to "input" iff pin is open-drain and reset
1881 		 * value is 1.
1882 		 */
1883 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1884 			priv->gpio_input |= BIT(i);
1885 	}
1886 
1887 	return 0;
1888 }
1889 
1890 static int cp210x_gpio_init(struct usb_serial *serial)
1891 {
1892 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1893 	int result;
1894 
1895 	switch (priv->partnum) {
1896 	case CP210X_PARTNUM_CP2104:
1897 		result = cp2104_gpioconf_init(serial);
1898 		break;
1899 	case CP210X_PARTNUM_CP2105:
1900 		result = cp2105_gpioconf_init(serial);
1901 		break;
1902 	case CP210X_PARTNUM_CP2108:
1903 		/*
1904 		 * The GPIOs are not tied to any specific port so only register
1905 		 * once for interface 0.
1906 		 */
1907 		if (cp210x_interface_num(serial) != 0)
1908 			return 0;
1909 		result = cp2108_gpio_init(serial);
1910 		break;
1911 	case CP210X_PARTNUM_CP2102N_QFN28:
1912 	case CP210X_PARTNUM_CP2102N_QFN24:
1913 	case CP210X_PARTNUM_CP2102N_QFN20:
1914 		result = cp2102n_gpioconf_init(serial);
1915 		break;
1916 	default:
1917 		return 0;
1918 	}
1919 
1920 	if (result < 0)
1921 		return result;
1922 
1923 	priv->gc.label = "cp210x";
1924 	priv->gc.get_direction = cp210x_gpio_direction_get;
1925 	priv->gc.direction_input = cp210x_gpio_direction_input;
1926 	priv->gc.direction_output = cp210x_gpio_direction_output;
1927 	priv->gc.get = cp210x_gpio_get;
1928 	priv->gc.set = cp210x_gpio_set;
1929 	priv->gc.set_config = cp210x_gpio_set_config;
1930 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1931 	priv->gc.owner = THIS_MODULE;
1932 	priv->gc.parent = &serial->interface->dev;
1933 	priv->gc.base = -1;
1934 	priv->gc.can_sleep = true;
1935 
1936 	result = gpiochip_add_data(&priv->gc, serial);
1937 	if (!result)
1938 		priv->gpio_registered = true;
1939 
1940 	return result;
1941 }
1942 
1943 static void cp210x_gpio_remove(struct usb_serial *serial)
1944 {
1945 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1946 
1947 	if (priv->gpio_registered) {
1948 		gpiochip_remove(&priv->gc);
1949 		priv->gpio_registered = false;
1950 	}
1951 }
1952 
1953 #else
1954 
1955 static int cp210x_gpio_init(struct usb_serial *serial)
1956 {
1957 	return 0;
1958 }
1959 
1960 static void cp210x_gpio_remove(struct usb_serial *serial)
1961 {
1962 	/* Nothing to do */
1963 }
1964 
1965 #endif
1966 
1967 static int cp210x_port_probe(struct usb_serial_port *port)
1968 {
1969 	struct usb_serial *serial = port->serial;
1970 	struct cp210x_port_private *port_priv;
1971 
1972 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1973 	if (!port_priv)
1974 		return -ENOMEM;
1975 
1976 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1977 	mutex_init(&port_priv->mutex);
1978 
1979 	usb_set_serial_port_data(port, port_priv);
1980 
1981 	return 0;
1982 }
1983 
1984 static void cp210x_port_remove(struct usb_serial_port *port)
1985 {
1986 	struct cp210x_port_private *port_priv;
1987 
1988 	port_priv = usb_get_serial_port_data(port);
1989 	kfree(port_priv);
1990 }
1991 
1992 static void cp210x_init_max_speed(struct usb_serial *serial)
1993 {
1994 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1995 	bool use_actual_rate = false;
1996 	speed_t min = 300;
1997 	speed_t max;
1998 
1999 	switch (priv->partnum) {
2000 	case CP210X_PARTNUM_CP2101:
2001 		max = 921600;
2002 		break;
2003 	case CP210X_PARTNUM_CP2102:
2004 	case CP210X_PARTNUM_CP2103:
2005 		max = 1000000;
2006 		break;
2007 	case CP210X_PARTNUM_CP2104:
2008 		use_actual_rate = true;
2009 		max = 2000000;
2010 		break;
2011 	case CP210X_PARTNUM_CP2108:
2012 		max = 2000000;
2013 		break;
2014 	case CP210X_PARTNUM_CP2105:
2015 		if (cp210x_interface_num(serial) == 0) {
2016 			use_actual_rate = true;
2017 			max = 2000000;	/* ECI */
2018 		} else {
2019 			min = 2400;
2020 			max = 921600;	/* SCI */
2021 		}
2022 		break;
2023 	case CP210X_PARTNUM_CP2102N_QFN28:
2024 	case CP210X_PARTNUM_CP2102N_QFN24:
2025 	case CP210X_PARTNUM_CP2102N_QFN20:
2026 		use_actual_rate = true;
2027 		max = 3000000;
2028 		break;
2029 	default:
2030 		max = 2000000;
2031 		break;
2032 	}
2033 
2034 	priv->min_speed = min;
2035 	priv->max_speed = max;
2036 	priv->use_actual_rate = use_actual_rate;
2037 }
2038 
2039 static void cp2102_determine_quirks(struct usb_serial *serial)
2040 {
2041 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2042 	u8 *buf;
2043 	int ret;
2044 
2045 	buf = kmalloc(2, GFP_KERNEL);
2046 	if (!buf)
2047 		return;
2048 	/*
2049 	 * Some (possibly counterfeit) CP2102 do not support event-insertion
2050 	 * mode and respond differently to malformed vendor requests.
2051 	 * Specifically, they return one instead of two bytes when sent a
2052 	 * two-byte part-number request.
2053 	 */
2054 	ret = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2055 			CP210X_VENDOR_SPECIFIC, REQTYPE_DEVICE_TO_HOST,
2056 			CP210X_GET_PARTNUM, 0, buf, 2, USB_CTRL_GET_TIMEOUT);
2057 	if (ret == 1) {
2058 		dev_dbg(&serial->interface->dev,
2059 				"device does not support event-insertion mode\n");
2060 		priv->no_event_mode = true;
2061 	}
2062 
2063 	kfree(buf);
2064 }
2065 
2066 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2067 {
2068 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2069 	u8 ver[3];
2070 	int ret;
2071 
2072 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2073 			ver, sizeof(ver));
2074 	if (ret)
2075 		return ret;
2076 
2077 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2078 			ver[0], ver[1], ver[2]);
2079 
2080 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2081 
2082 	return 0;
2083 }
2084 
2085 static void cp210x_determine_type(struct usb_serial *serial)
2086 {
2087 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2088 	int ret;
2089 
2090 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2091 			CP210X_GET_PARTNUM, &priv->partnum,
2092 			sizeof(priv->partnum));
2093 	if (ret < 0) {
2094 		dev_warn(&serial->interface->dev,
2095 				"querying part number failed\n");
2096 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2097 		return;
2098 	}
2099 
2100 	dev_dbg(&serial->interface->dev, "partnum = 0x%02x\n", priv->partnum);
2101 
2102 	switch (priv->partnum) {
2103 	case CP210X_PARTNUM_CP2102:
2104 		cp2102_determine_quirks(serial);
2105 		break;
2106 	case CP210X_PARTNUM_CP2105:
2107 	case CP210X_PARTNUM_CP2108:
2108 		cp210x_get_fw_version(serial, CP210X_GET_FW_VER);
2109 		break;
2110 	case CP210X_PARTNUM_CP2102N_QFN28:
2111 	case CP210X_PARTNUM_CP2102N_QFN24:
2112 	case CP210X_PARTNUM_CP2102N_QFN20:
2113 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2114 		if (ret)
2115 			break;
2116 		if (priv->fw_version <= 0x10004)
2117 			priv->no_flow_control = true;
2118 		break;
2119 	default:
2120 		break;
2121 	}
2122 }
2123 
2124 static int cp210x_attach(struct usb_serial *serial)
2125 {
2126 	int result;
2127 	struct cp210x_serial_private *priv;
2128 
2129 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2130 	if (!priv)
2131 		return -ENOMEM;
2132 
2133 	usb_set_serial_data(serial, priv);
2134 
2135 	cp210x_determine_type(serial);
2136 	cp210x_init_max_speed(serial);
2137 
2138 	result = cp210x_gpio_init(serial);
2139 	if (result < 0) {
2140 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2141 				result);
2142 	}
2143 
2144 	return 0;
2145 }
2146 
2147 static void cp210x_disconnect(struct usb_serial *serial)
2148 {
2149 	cp210x_gpio_remove(serial);
2150 }
2151 
2152 static void cp210x_release(struct usb_serial *serial)
2153 {
2154 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2155 
2156 	cp210x_gpio_remove(serial);
2157 
2158 	kfree(priv);
2159 }
2160 
2161 module_usb_serial_driver(serial_drivers, id_table);
2162 
2163 MODULE_DESCRIPTION(DRIVER_DESC);
2164 MODULE_LICENSE("GPL v2");
2165