xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 9f99d983)
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(0x106F, 0x0003) },	/* CPI / Money Controls Bulk Coin Recycler */
73 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
74 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
75 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
76 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
77 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
78 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
79 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
80 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
81 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
82 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
83 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
84 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
85 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
86 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
87 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
88 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
89 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
90 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
91 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
92 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
93 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
94 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
95 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
96 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
97 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
98 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
99 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
100 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
101 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
102 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
104 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
105 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
106 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
107 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
108 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
109 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
110 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
111 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
112 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
113 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
114 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
115 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
116 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
117 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
118 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
119 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
120 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
121 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
122 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
123 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
124 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
125 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
126 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
127 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
128 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
129 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
130 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
131 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
132 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
133 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
134 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
135 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
136 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
137 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
138 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
139 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
140 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
141 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
142 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
143 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
144 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
145 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
146 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
147 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
148 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
149 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
150 	{ USB_DEVICE(0x10C4, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
151 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
152 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
153 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
154 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
155 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
156 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
157 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
158 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
159 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
160 	{ USB_DEVICE(0x10C4, 0x8A5B) }, /* CEL EM3588 ZigBee USB Stick */
161 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
162 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
163 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
164 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
165 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
166 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
167 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
168 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
169 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
170 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
171 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
172 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
173 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
174 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
175 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
176 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
177 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
178 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
179 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
180 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
181 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
182 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
183 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
184 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
185 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
186 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
187 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
188 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
189 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
190 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
191 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
192 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
193 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
194 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
195 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
196 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
197 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
198 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
199 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
200 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
201 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
202 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
203 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
204 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
205 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
206 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
207 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
208 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 M.2 Key E serial interface */
209 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 Display serial interface */
210 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
211 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
212 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
213 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
214 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
215 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
216 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
217 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
218 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
219 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
220 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
221 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
222 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
223 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
224 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
225 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
226 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
227 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
228 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
229 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
230 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
231 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
232 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
233 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
234 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
235 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
236 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
237 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
238 	{ USB_DEVICE(0x2184, 0x0030) }, /* GW Instek GDM-834x Digital Multimeter */
239 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
240 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
241 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
242 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
243 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
244 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
245 	{ } /* Terminating Entry */
246 };
247 
248 MODULE_DEVICE_TABLE(usb, id_table);
249 
250 struct cp210x_serial_private {
251 #ifdef CONFIG_GPIOLIB
252 	struct gpio_chip	gc;
253 	bool			gpio_registered;
254 	u16			gpio_pushpull;
255 	u16			gpio_altfunc;
256 	u16			gpio_input;
257 #endif
258 	u8			partnum;
259 	u32			fw_version;
260 	speed_t			min_speed;
261 	speed_t			max_speed;
262 	bool			use_actual_rate;
263 	bool			no_flow_control;
264 	bool			no_event_mode;
265 };
266 
267 enum cp210x_event_state {
268 	ES_DATA,
269 	ES_ESCAPE,
270 	ES_LSR,
271 	ES_LSR_DATA_0,
272 	ES_LSR_DATA_1,
273 	ES_MSR
274 };
275 
276 struct cp210x_port_private {
277 	u8			bInterfaceNumber;
278 	bool			event_mode;
279 	enum cp210x_event_state event_state;
280 	u8			lsr;
281 
282 	struct mutex		mutex;
283 	bool			crtscts;
284 	bool			dtr;
285 	bool			rts;
286 };
287 
288 static struct usb_serial_driver cp210x_device = {
289 	.driver = {
290 		.owner =	THIS_MODULE,
291 		.name =		"cp210x",
292 	},
293 	.id_table		= id_table,
294 	.num_ports		= 1,
295 	.bulk_in_size		= 256,
296 	.bulk_out_size		= 256,
297 	.open			= cp210x_open,
298 	.close			= cp210x_close,
299 	.break_ctl		= cp210x_break_ctl,
300 	.set_termios		= cp210x_set_termios,
301 	.tx_empty		= cp210x_tx_empty,
302 	.throttle		= usb_serial_generic_throttle,
303 	.unthrottle		= usb_serial_generic_unthrottle,
304 	.tiocmget		= cp210x_tiocmget,
305 	.tiocmset		= cp210x_tiocmset,
306 	.get_icount		= usb_serial_generic_get_icount,
307 	.attach			= cp210x_attach,
308 	.disconnect		= cp210x_disconnect,
309 	.release		= cp210x_release,
310 	.port_probe		= cp210x_port_probe,
311 	.port_remove		= cp210x_port_remove,
312 	.dtr_rts		= cp210x_dtr_rts,
313 	.process_read_urb	= cp210x_process_read_urb,
314 };
315 
316 static struct usb_serial_driver * const serial_drivers[] = {
317 	&cp210x_device, NULL
318 };
319 
320 /* Config request types */
321 #define REQTYPE_HOST_TO_INTERFACE	0x41
322 #define REQTYPE_INTERFACE_TO_HOST	0xc1
323 #define REQTYPE_HOST_TO_DEVICE	0x40
324 #define REQTYPE_DEVICE_TO_HOST	0xc0
325 
326 /* Config request codes */
327 #define CP210X_IFC_ENABLE	0x00
328 #define CP210X_SET_BAUDDIV	0x01
329 #define CP210X_GET_BAUDDIV	0x02
330 #define CP210X_SET_LINE_CTL	0x03
331 #define CP210X_GET_LINE_CTL	0x04
332 #define CP210X_SET_BREAK	0x05
333 #define CP210X_IMM_CHAR		0x06
334 #define CP210X_SET_MHS		0x07
335 #define CP210X_GET_MDMSTS	0x08
336 #define CP210X_SET_XON		0x09
337 #define CP210X_SET_XOFF		0x0A
338 #define CP210X_SET_EVENTMASK	0x0B
339 #define CP210X_GET_EVENTMASK	0x0C
340 #define CP210X_SET_CHAR		0x0D
341 #define CP210X_GET_CHARS	0x0E
342 #define CP210X_GET_PROPS	0x0F
343 #define CP210X_GET_COMM_STATUS	0x10
344 #define CP210X_RESET		0x11
345 #define CP210X_PURGE		0x12
346 #define CP210X_SET_FLOW		0x13
347 #define CP210X_GET_FLOW		0x14
348 #define CP210X_EMBED_EVENTS	0x15
349 #define CP210X_GET_EVENTSTATE	0x16
350 #define CP210X_SET_CHARS	0x19
351 #define CP210X_GET_BAUDRATE	0x1D
352 #define CP210X_SET_BAUDRATE	0x1E
353 #define CP210X_VENDOR_SPECIFIC	0xFF
354 
355 /* CP210X_IFC_ENABLE */
356 #define UART_ENABLE		0x0001
357 #define UART_DISABLE		0x0000
358 
359 /* CP210X_(SET|GET)_BAUDDIV */
360 #define BAUD_RATE_GEN_FREQ	0x384000
361 
362 /* CP210X_(SET|GET)_LINE_CTL */
363 #define BITS_DATA_MASK		0X0f00
364 #define BITS_DATA_5		0X0500
365 #define BITS_DATA_6		0X0600
366 #define BITS_DATA_7		0X0700
367 #define BITS_DATA_8		0X0800
368 #define BITS_DATA_9		0X0900
369 
370 #define BITS_PARITY_MASK	0x00f0
371 #define BITS_PARITY_NONE	0x0000
372 #define BITS_PARITY_ODD		0x0010
373 #define BITS_PARITY_EVEN	0x0020
374 #define BITS_PARITY_MARK	0x0030
375 #define BITS_PARITY_SPACE	0x0040
376 
377 #define BITS_STOP_MASK		0x000f
378 #define BITS_STOP_1		0x0000
379 #define BITS_STOP_1_5		0x0001
380 #define BITS_STOP_2		0x0002
381 
382 /* CP210X_SET_BREAK */
383 #define BREAK_ON		0x0001
384 #define BREAK_OFF		0x0000
385 
386 /* CP210X_(SET_MHS|GET_MDMSTS) */
387 #define CONTROL_DTR		0x0001
388 #define CONTROL_RTS		0x0002
389 #define CONTROL_CTS		0x0010
390 #define CONTROL_DSR		0x0020
391 #define CONTROL_RING		0x0040
392 #define CONTROL_DCD		0x0080
393 #define CONTROL_WRITE_DTR	0x0100
394 #define CONTROL_WRITE_RTS	0x0200
395 
396 /* CP210X_(GET|SET)_CHARS */
397 struct cp210x_special_chars {
398 	u8	bEofChar;
399 	u8	bErrorChar;
400 	u8	bBreakChar;
401 	u8	bEventChar;
402 	u8	bXonChar;
403 	u8	bXoffChar;
404 };
405 
406 /* CP210X_VENDOR_SPECIFIC values */
407 #define CP210X_GET_FW_VER	0x000E
408 #define CP210X_READ_2NCONFIG	0x000E
409 #define CP210X_GET_FW_VER_2N	0x0010
410 #define CP210X_READ_LATCH	0x00C2
411 #define CP210X_GET_PARTNUM	0x370B
412 #define CP210X_GET_PORTCONFIG	0x370C
413 #define CP210X_GET_DEVICEMODE	0x3711
414 #define CP210X_WRITE_LATCH	0x37E1
415 
416 /* Part number definitions */
417 #define CP210X_PARTNUM_CP2101	0x01
418 #define CP210X_PARTNUM_CP2102	0x02
419 #define CP210X_PARTNUM_CP2103	0x03
420 #define CP210X_PARTNUM_CP2104	0x04
421 #define CP210X_PARTNUM_CP2105	0x05
422 #define CP210X_PARTNUM_CP2108	0x08
423 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
424 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
425 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
426 #define CP210X_PARTNUM_UNKNOWN	0xFF
427 
428 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
429 struct cp210x_comm_status {
430 	__le32   ulErrors;
431 	__le32   ulHoldReasons;
432 	__le32   ulAmountInInQueue;
433 	__le32   ulAmountInOutQueue;
434 	u8       bEofReceived;
435 	u8       bWaitForImmediate;
436 	u8       bReserved;
437 } __packed;
438 
439 /*
440  * CP210X_PURGE - 16 bits passed in wValue of USB request.
441  * SiLabs app note AN571 gives a strange description of the 4 bits:
442  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
443  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
444  */
445 #define PURGE_ALL		0x000f
446 
447 /* CP210X_EMBED_EVENTS */
448 #define CP210X_ESCCHAR		0xec
449 
450 #define CP210X_LSR_OVERRUN	BIT(1)
451 #define CP210X_LSR_PARITY	BIT(2)
452 #define CP210X_LSR_FRAME	BIT(3)
453 #define CP210X_LSR_BREAK	BIT(4)
454 
455 
456 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
457 struct cp210x_flow_ctl {
458 	__le32	ulControlHandshake;
459 	__le32	ulFlowReplace;
460 	__le32	ulXonLimit;
461 	__le32	ulXoffLimit;
462 };
463 
464 /* cp210x_flow_ctl::ulControlHandshake */
465 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
466 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
467 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
468 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
469 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
470 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
471 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
472 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
473 
474 /* cp210x_flow_ctl::ulFlowReplace */
475 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
476 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
477 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
478 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
479 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
480 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
481 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
482 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
483 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
484 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
485 
486 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
487 struct cp210x_pin_mode {
488 	u8	eci;
489 	u8	sci;
490 };
491 
492 #define CP210X_PIN_MODE_MODEM		0
493 #define CP210X_PIN_MODE_GPIO		BIT(0)
494 
495 /*
496  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
497  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
498  */
499 struct cp210x_dual_port_config {
500 	__le16	gpio_mode;
501 	u8	__pad0[2];
502 	__le16	reset_state;
503 	u8	__pad1[4];
504 	__le16	suspend_state;
505 	u8	sci_cfg;
506 	u8	eci_cfg;
507 	u8	device_cfg;
508 } __packed;
509 
510 /*
511  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
512  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
513  */
514 struct cp210x_single_port_config {
515 	__le16	gpio_mode;
516 	u8	__pad0[2];
517 	__le16	reset_state;
518 	u8	__pad1[4];
519 	__le16	suspend_state;
520 	u8	device_cfg;
521 } __packed;
522 
523 /* GPIO modes */
524 #define CP210X_SCI_GPIO_MODE_OFFSET	9
525 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
526 
527 #define CP210X_ECI_GPIO_MODE_OFFSET	2
528 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
529 
530 #define CP210X_GPIO_MODE_OFFSET		8
531 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
532 
533 /* CP2105 port configuration values */
534 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
535 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
536 #define CP2105_GPIO1_RS485_MODE		BIT(2)
537 
538 /* CP2104 port configuration values */
539 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
540 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
541 #define CP2104_GPIO2_RS485_MODE		BIT(2)
542 
543 struct cp210x_quad_port_state {
544 	__le16 gpio_mode_pb0;
545 	__le16 gpio_mode_pb1;
546 	__le16 gpio_mode_pb2;
547 	__le16 gpio_mode_pb3;
548 	__le16 gpio_mode_pb4;
549 
550 	__le16 gpio_lowpower_pb0;
551 	__le16 gpio_lowpower_pb1;
552 	__le16 gpio_lowpower_pb2;
553 	__le16 gpio_lowpower_pb3;
554 	__le16 gpio_lowpower_pb4;
555 
556 	__le16 gpio_latch_pb0;
557 	__le16 gpio_latch_pb1;
558 	__le16 gpio_latch_pb2;
559 	__le16 gpio_latch_pb3;
560 	__le16 gpio_latch_pb4;
561 };
562 
563 /*
564  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
565  * on a CP2108 chip.
566  *
567  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
568  */
569 struct cp210x_quad_port_config {
570 	struct cp210x_quad_port_state reset_state;
571 	struct cp210x_quad_port_state suspend_state;
572 	u8 ipdelay_ifc[4];
573 	u8 enhancedfxn_ifc[4];
574 	u8 enhancedfxn_device;
575 	u8 extclkfreq[4];
576 } __packed;
577 
578 #define CP2108_EF_IFC_GPIO_TXLED		0x01
579 #define CP2108_EF_IFC_GPIO_RXLED		0x02
580 #define CP2108_EF_IFC_GPIO_RS485		0x04
581 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
582 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
583 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
584 
585 /* CP2102N configuration array indices */
586 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
587 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
588 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
589 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
590 
591 /* CP2102N QFN20 port configuration values */
592 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
593 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
594 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
595 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
596 
597 /*
598  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
599  * for CP2102N, CP2103, CP2104 and CP2105.
600  */
601 struct cp210x_gpio_write {
602 	u8	mask;
603 	u8	state;
604 };
605 
606 /*
607  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
608  * for CP2108.
609  */
610 struct cp210x_gpio_write16 {
611 	__le16	mask;
612 	__le16	state;
613 };
614 
615 /*
616  * Helper to get interface number when we only have struct usb_serial.
617  */
618 static u8 cp210x_interface_num(struct usb_serial *serial)
619 {
620 	struct usb_host_interface *cur_altsetting;
621 
622 	cur_altsetting = serial->interface->cur_altsetting;
623 
624 	return cur_altsetting->desc.bInterfaceNumber;
625 }
626 
627 /*
628  * Reads a variable-sized block of CP210X_ registers, identified by req.
629  * Returns data into buf in native USB byte order.
630  */
631 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
632 		void *buf, int bufsize)
633 {
634 	struct usb_serial *serial = port->serial;
635 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
636 	int result;
637 
638 
639 	result = usb_control_msg_recv(serial->dev, 0, req,
640 			REQTYPE_INTERFACE_TO_HOST, 0,
641 			port_priv->bInterfaceNumber, buf, bufsize,
642 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
643 	if (result) {
644 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
645 				req, bufsize, result);
646 		return result;
647 	}
648 
649 	return 0;
650 }
651 
652 /*
653  * Reads any 8-bit CP210X_ register identified by req.
654  */
655 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
656 {
657 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
658 }
659 
660 /*
661  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
662  * Returns data into buf in native USB byte order.
663  */
664 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
665 				    void *buf, int bufsize)
666 {
667 	int result;
668 
669 	result = usb_control_msg_recv(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
670 			type, val, cp210x_interface_num(serial), buf, bufsize,
671 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
672 	if (result) {
673 		dev_err(&serial->interface->dev,
674 			"failed to get vendor val 0x%04x size %d: %d\n", val,
675 			bufsize, result);
676 		return result;
677 	}
678 
679 	return 0;
680 }
681 
682 /*
683  * Writes any 16-bit CP210X_ register (req) whose value is passed
684  * entirely in the wValue field of the USB request.
685  */
686 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
687 {
688 	struct usb_serial *serial = port->serial;
689 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
690 	int result;
691 
692 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
693 			req, REQTYPE_HOST_TO_INTERFACE, val,
694 			port_priv->bInterfaceNumber, NULL, 0,
695 			USB_CTRL_SET_TIMEOUT);
696 	if (result < 0) {
697 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
698 				req, result);
699 	}
700 
701 	return result;
702 }
703 
704 /*
705  * Writes a variable-sized block of CP210X_ registers, identified by req.
706  * Data in buf must be in native USB byte order.
707  */
708 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
709 		void *buf, int bufsize)
710 {
711 	struct usb_serial *serial = port->serial;
712 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
713 	int result;
714 
715 	result = usb_control_msg_send(serial->dev, 0, req,
716 			REQTYPE_HOST_TO_INTERFACE, 0,
717 			port_priv->bInterfaceNumber, buf, bufsize,
718 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
719 	if (result) {
720 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
721 				req, bufsize, result);
722 		return result;
723 	}
724 
725 	return 0;
726 }
727 
728 /*
729  * Writes any 32-bit CP210X_ register identified by req.
730  */
731 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
732 {
733 	__le32 le32_val;
734 
735 	le32_val = cpu_to_le32(val);
736 
737 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
738 }
739 
740 #ifdef CONFIG_GPIOLIB
741 /*
742  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
743  * Data in buf must be in native USB byte order.
744  */
745 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
746 				     u16 val, void *buf, int bufsize)
747 {
748 	int result;
749 
750 	result = usb_control_msg_send(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
751 			type, val, cp210x_interface_num(serial), buf, bufsize,
752 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
753 	if (result) {
754 		dev_err(&serial->interface->dev,
755 			"failed to set vendor val 0x%04x size %d: %d\n", val,
756 			bufsize, result);
757 		return result;
758 	}
759 
760 	return 0;
761 }
762 #endif
763 
764 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
765 {
766 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
767 	int result;
768 
769 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
770 	if (result) {
771 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
772 		return result;
773 	}
774 
775 	if (tty)
776 		cp210x_set_termios(tty, port, NULL);
777 
778 	result = usb_serial_generic_open(tty, port);
779 	if (result)
780 		goto err_disable;
781 
782 	return 0;
783 
784 err_disable:
785 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
786 	port_priv->event_mode = false;
787 
788 	return result;
789 }
790 
791 static void cp210x_close(struct usb_serial_port *port)
792 {
793 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
794 
795 	usb_serial_generic_close(port);
796 
797 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
798 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
799 
800 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
801 
802 	/* Disabling the interface disables event-insertion mode. */
803 	port_priv->event_mode = false;
804 }
805 
806 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
807 {
808 	if (lsr & CP210X_LSR_BREAK) {
809 		port->icount.brk++;
810 		*flag = TTY_BREAK;
811 	} else if (lsr & CP210X_LSR_PARITY) {
812 		port->icount.parity++;
813 		*flag = TTY_PARITY;
814 	} else if (lsr & CP210X_LSR_FRAME) {
815 		port->icount.frame++;
816 		*flag = TTY_FRAME;
817 	}
818 
819 	if (lsr & CP210X_LSR_OVERRUN) {
820 		port->icount.overrun++;
821 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
822 	}
823 }
824 
825 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
826 {
827 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
828 
829 	switch (port_priv->event_state) {
830 	case ES_DATA:
831 		if (*ch == CP210X_ESCCHAR) {
832 			port_priv->event_state = ES_ESCAPE;
833 			break;
834 		}
835 		return false;
836 	case ES_ESCAPE:
837 		switch (*ch) {
838 		case 0:
839 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
840 			*ch = CP210X_ESCCHAR;
841 			port_priv->event_state = ES_DATA;
842 			return false;
843 		case 1:
844 			port_priv->event_state = ES_LSR_DATA_0;
845 			break;
846 		case 2:
847 			port_priv->event_state = ES_LSR;
848 			break;
849 		case 3:
850 			port_priv->event_state = ES_MSR;
851 			break;
852 		default:
853 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
854 			port_priv->event_state = ES_DATA;
855 			break;
856 		}
857 		break;
858 	case ES_LSR_DATA_0:
859 		port_priv->lsr = *ch;
860 		port_priv->event_state = ES_LSR_DATA_1;
861 		break;
862 	case ES_LSR_DATA_1:
863 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
864 				__func__, port_priv->lsr, *ch);
865 		cp210x_process_lsr(port, port_priv->lsr, flag);
866 		port_priv->event_state = ES_DATA;
867 		return false;
868 	case ES_LSR:
869 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
870 		port_priv->lsr = *ch;
871 		cp210x_process_lsr(port, port_priv->lsr, flag);
872 		port_priv->event_state = ES_DATA;
873 		break;
874 	case ES_MSR:
875 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
876 		/* unimplemented */
877 		port_priv->event_state = ES_DATA;
878 		break;
879 	}
880 
881 	return true;
882 }
883 
884 static void cp210x_process_read_urb(struct urb *urb)
885 {
886 	struct usb_serial_port *port = urb->context;
887 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
888 	unsigned char *ch = urb->transfer_buffer;
889 	char flag;
890 	int i;
891 
892 	if (!urb->actual_length)
893 		return;
894 
895 	if (port_priv->event_mode) {
896 		for (i = 0; i < urb->actual_length; i++, ch++) {
897 			flag = TTY_NORMAL;
898 
899 			if (cp210x_process_char(port, ch, &flag))
900 				continue;
901 
902 			tty_insert_flip_char(&port->port, *ch, flag);
903 		}
904 	} else {
905 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
906 	}
907 	tty_flip_buffer_push(&port->port);
908 }
909 
910 /*
911  * Read how many bytes are waiting in the TX queue.
912  */
913 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
914 		u32 *count)
915 {
916 	struct usb_serial *serial = port->serial;
917 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
918 	struct cp210x_comm_status sts;
919 	int result;
920 
921 	result = usb_control_msg_recv(serial->dev, 0, CP210X_GET_COMM_STATUS,
922 			REQTYPE_INTERFACE_TO_HOST, 0,
923 			port_priv->bInterfaceNumber, &sts, sizeof(sts),
924 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
925 	if (result) {
926 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
927 		return result;
928 	}
929 
930 	*count = le32_to_cpu(sts.ulAmountInOutQueue);
931 
932 	return 0;
933 }
934 
935 static bool cp210x_tx_empty(struct usb_serial_port *port)
936 {
937 	int err;
938 	u32 count;
939 
940 	err = cp210x_get_tx_queue_byte_count(port, &count);
941 	if (err)
942 		return true;
943 
944 	return !count;
945 }
946 
947 struct cp210x_rate {
948 	speed_t rate;
949 	speed_t high;
950 };
951 
952 static const struct cp210x_rate cp210x_an205_table1[] = {
953 	{ 300, 300 },
954 	{ 600, 600 },
955 	{ 1200, 1200 },
956 	{ 1800, 1800 },
957 	{ 2400, 2400 },
958 	{ 4000, 4000 },
959 	{ 4800, 4803 },
960 	{ 7200, 7207 },
961 	{ 9600, 9612 },
962 	{ 14400, 14428 },
963 	{ 16000, 16062 },
964 	{ 19200, 19250 },
965 	{ 28800, 28912 },
966 	{ 38400, 38601 },
967 	{ 51200, 51558 },
968 	{ 56000, 56280 },
969 	{ 57600, 58053 },
970 	{ 64000, 64111 },
971 	{ 76800, 77608 },
972 	{ 115200, 117028 },
973 	{ 128000, 129347 },
974 	{ 153600, 156868 },
975 	{ 230400, 237832 },
976 	{ 250000, 254234 },
977 	{ 256000, 273066 },
978 	{ 460800, 491520 },
979 	{ 500000, 567138 },
980 	{ 576000, 670254 },
981 	{ 921600, UINT_MAX }
982 };
983 
984 /*
985  * Quantises the baud rate as per AN205 Table 1
986  */
987 static speed_t cp210x_get_an205_rate(speed_t baud)
988 {
989 	int i;
990 
991 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
992 		if (baud <= cp210x_an205_table1[i].high)
993 			break;
994 	}
995 
996 	return cp210x_an205_table1[i].rate;
997 }
998 
999 static speed_t cp210x_get_actual_rate(speed_t baud)
1000 {
1001 	unsigned int prescale = 1;
1002 	unsigned int div;
1003 
1004 	if (baud <= 365)
1005 		prescale = 4;
1006 
1007 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1008 	baud = 48000000 / (2 * prescale * div);
1009 
1010 	return baud;
1011 }
1012 
1013 /*
1014  * CP2101 supports the following baud rates:
1015  *
1016  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1017  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1018  *
1019  * CP2102 and CP2103 support the following additional rates:
1020  *
1021  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1022  *	576000
1023  *
1024  * The device will map a requested rate to a supported one, but the result
1025  * of requests for rates greater than 1053257 is undefined (see AN205).
1026  *
1027  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1028  * respectively, with an error less than 1%. The actual rates are determined
1029  * by
1030  *
1031  *	div = round(freq / (2 x prescale x request))
1032  *	actual = freq / (2 x prescale x div)
1033  *
1034  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1035  * or 1 otherwise.
1036  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1037  * otherwise.
1038  */
1039 static void cp210x_change_speed(struct tty_struct *tty,
1040 		struct usb_serial_port *port, struct ktermios *old_termios)
1041 {
1042 	struct usb_serial *serial = port->serial;
1043 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1044 	u32 baud;
1045 
1046 	/*
1047 	 * This maps the requested rate to the actual rate, a valid rate on
1048 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1049 	 *
1050 	 * NOTE: B0 is not implemented.
1051 	 */
1052 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1053 
1054 	if (priv->use_actual_rate)
1055 		baud = cp210x_get_actual_rate(baud);
1056 	else if (baud < 1000000)
1057 		baud = cp210x_get_an205_rate(baud);
1058 
1059 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1060 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1061 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1062 		if (old_termios)
1063 			baud = old_termios->c_ospeed;
1064 		else
1065 			baud = 9600;
1066 	}
1067 
1068 	tty_encode_baud_rate(tty, baud, baud);
1069 }
1070 
1071 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1072 {
1073 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1074 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1075 	int ret;
1076 
1077 	if (port_priv->event_mode)
1078 		return;
1079 
1080 	if (priv->no_event_mode)
1081 		return;
1082 
1083 	port_priv->event_state = ES_DATA;
1084 	port_priv->event_mode = true;
1085 
1086 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1087 	if (ret) {
1088 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1089 		port_priv->event_mode = false;
1090 	}
1091 }
1092 
1093 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1094 {
1095 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1096 	int ret;
1097 
1098 	if (!port_priv->event_mode)
1099 		return;
1100 
1101 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1102 	if (ret) {
1103 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1104 		return;
1105 	}
1106 
1107 	port_priv->event_mode = false;
1108 }
1109 
1110 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1111 {
1112 	bool iflag_change, cc_change;
1113 
1114 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1115 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1116 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1117 
1118 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1119 }
1120 
1121 static void cp210x_set_flow_control(struct tty_struct *tty,
1122 		struct usb_serial_port *port, struct ktermios *old_termios)
1123 {
1124 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1125 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1126 	struct cp210x_special_chars chars;
1127 	struct cp210x_flow_ctl flow_ctl;
1128 	u32 flow_repl;
1129 	u32 ctl_hs;
1130 	bool crtscts;
1131 	int ret;
1132 
1133 	/*
1134 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1135 	 * CP2102N_E104). Report back that flow control is not supported.
1136 	 */
1137 	if (priv->no_flow_control) {
1138 		tty->termios.c_cflag &= ~CRTSCTS;
1139 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1140 	}
1141 
1142 	if (old_termios &&
1143 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1144 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1145 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1146 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1147 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1148 		return;
1149 	}
1150 
1151 	if (I_IXON(tty) || I_IXOFF(tty)) {
1152 		memset(&chars, 0, sizeof(chars));
1153 
1154 		chars.bXonChar = START_CHAR(tty);
1155 		chars.bXoffChar = STOP_CHAR(tty);
1156 
1157 		ret = cp210x_write_reg_block(port, CP210X_SET_CHARS, &chars,
1158 				sizeof(chars));
1159 		if (ret) {
1160 			dev_err(&port->dev, "failed to set special chars: %d\n",
1161 					ret);
1162 		}
1163 	}
1164 
1165 	mutex_lock(&port_priv->mutex);
1166 
1167 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1168 			sizeof(flow_ctl));
1169 	if (ret)
1170 		goto out_unlock;
1171 
1172 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1173 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1174 
1175 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1176 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1177 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1178 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1179 	if (port_priv->dtr)
1180 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1181 	else
1182 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1183 
1184 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1185 	if (C_CRTSCTS(tty)) {
1186 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1187 		if (port_priv->rts)
1188 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1189 		else
1190 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1191 		crtscts = true;
1192 	} else {
1193 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1194 		if (port_priv->rts)
1195 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1196 		else
1197 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1198 		crtscts = false;
1199 	}
1200 
1201 	if (I_IXOFF(tty)) {
1202 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1203 
1204 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1205 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1206 	} else {
1207 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1208 	}
1209 
1210 	if (I_IXON(tty))
1211 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1212 	else
1213 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1214 
1215 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1216 			ctl_hs, flow_repl);
1217 
1218 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1219 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1220 
1221 	ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1222 			sizeof(flow_ctl));
1223 	if (ret)
1224 		goto out_unlock;
1225 
1226 	port_priv->crtscts = crtscts;
1227 out_unlock:
1228 	mutex_unlock(&port_priv->mutex);
1229 }
1230 
1231 static void cp210x_set_termios(struct tty_struct *tty,
1232 		struct usb_serial_port *port, struct ktermios *old_termios)
1233 {
1234 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1235 	u16 bits;
1236 	int ret;
1237 
1238 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1239 		return;
1240 
1241 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1242 		cp210x_change_speed(tty, port, old_termios);
1243 
1244 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1245 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1246 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1247 		tty->termios.c_cflag |= CS8;
1248 	}
1249 
1250 	bits = 0;
1251 
1252 	switch (C_CSIZE(tty)) {
1253 	case CS5:
1254 		bits |= BITS_DATA_5;
1255 		break;
1256 	case CS6:
1257 		bits |= BITS_DATA_6;
1258 		break;
1259 	case CS7:
1260 		bits |= BITS_DATA_7;
1261 		break;
1262 	case CS8:
1263 	default:
1264 		bits |= BITS_DATA_8;
1265 		break;
1266 	}
1267 
1268 	if (C_PARENB(tty)) {
1269 		if (C_CMSPAR(tty)) {
1270 			if (C_PARODD(tty))
1271 				bits |= BITS_PARITY_MARK;
1272 			else
1273 				bits |= BITS_PARITY_SPACE;
1274 		} else {
1275 			if (C_PARODD(tty))
1276 				bits |= BITS_PARITY_ODD;
1277 			else
1278 				bits |= BITS_PARITY_EVEN;
1279 		}
1280 	}
1281 
1282 	if (C_CSTOPB(tty))
1283 		bits |= BITS_STOP_2;
1284 	else
1285 		bits |= BITS_STOP_1;
1286 
1287 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1288 	if (ret)
1289 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1290 
1291 	cp210x_set_flow_control(tty, port, old_termios);
1292 
1293 	/*
1294 	 * Enable event-insertion mode only if input parity checking is
1295 	 * enabled for now.
1296 	 */
1297 	if (I_INPCK(tty))
1298 		cp210x_enable_event_mode(port);
1299 	else
1300 		cp210x_disable_event_mode(port);
1301 }
1302 
1303 static int cp210x_tiocmset(struct tty_struct *tty,
1304 		unsigned int set, unsigned int clear)
1305 {
1306 	struct usb_serial_port *port = tty->driver_data;
1307 	return cp210x_tiocmset_port(port, set, clear);
1308 }
1309 
1310 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1311 		unsigned int set, unsigned int clear)
1312 {
1313 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1314 	struct cp210x_flow_ctl flow_ctl;
1315 	u32 ctl_hs, flow_repl;
1316 	u16 control = 0;
1317 	int ret;
1318 
1319 	mutex_lock(&port_priv->mutex);
1320 
1321 	if (set & TIOCM_RTS) {
1322 		port_priv->rts = true;
1323 		control |= CONTROL_RTS;
1324 		control |= CONTROL_WRITE_RTS;
1325 	}
1326 	if (set & TIOCM_DTR) {
1327 		port_priv->dtr = true;
1328 		control |= CONTROL_DTR;
1329 		control |= CONTROL_WRITE_DTR;
1330 	}
1331 	if (clear & TIOCM_RTS) {
1332 		port_priv->rts = false;
1333 		control &= ~CONTROL_RTS;
1334 		control |= CONTROL_WRITE_RTS;
1335 	}
1336 	if (clear & TIOCM_DTR) {
1337 		port_priv->dtr = false;
1338 		control &= ~CONTROL_DTR;
1339 		control |= CONTROL_WRITE_DTR;
1340 	}
1341 
1342 	/*
1343 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1344 	 * flow control is enabled.
1345 	 */
1346 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1347 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1348 				sizeof(flow_ctl));
1349 		if (ret)
1350 			goto out_unlock;
1351 
1352 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1353 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1354 
1355 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1356 		if (port_priv->dtr)
1357 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1358 		else
1359 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1360 
1361 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1362 		if (port_priv->rts)
1363 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1364 		else
1365 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1366 
1367 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1368 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1369 
1370 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1371 				__func__, ctl_hs, flow_repl);
1372 
1373 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1374 				sizeof(flow_ctl));
1375 	} else {
1376 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1377 
1378 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1379 	}
1380 out_unlock:
1381 	mutex_unlock(&port_priv->mutex);
1382 
1383 	return ret;
1384 }
1385 
1386 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1387 {
1388 	if (on)
1389 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1390 	else
1391 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1392 }
1393 
1394 static int cp210x_tiocmget(struct tty_struct *tty)
1395 {
1396 	struct usb_serial_port *port = tty->driver_data;
1397 	u8 control;
1398 	int result;
1399 
1400 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1401 	if (result)
1402 		return result;
1403 
1404 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1405 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1406 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1407 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1408 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1409 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1410 
1411 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1412 
1413 	return result;
1414 }
1415 
1416 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1417 {
1418 	struct usb_serial_port *port = tty->driver_data;
1419 	u16 state;
1420 
1421 	if (break_state == 0)
1422 		state = BREAK_OFF;
1423 	else
1424 		state = BREAK_ON;
1425 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1426 		state == BREAK_OFF ? "off" : "on");
1427 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1428 }
1429 
1430 #ifdef CONFIG_GPIOLIB
1431 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1432 {
1433 	struct usb_serial *serial = gpiochip_get_data(gc);
1434 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1435 	u8 req_type;
1436 	u16 mask;
1437 	int result;
1438 	int len;
1439 
1440 	result = usb_autopm_get_interface(serial->interface);
1441 	if (result)
1442 		return result;
1443 
1444 	switch (priv->partnum) {
1445 	case CP210X_PARTNUM_CP2105:
1446 		req_type = REQTYPE_INTERFACE_TO_HOST;
1447 		len = 1;
1448 		break;
1449 	case CP210X_PARTNUM_CP2108:
1450 		req_type = REQTYPE_INTERFACE_TO_HOST;
1451 		len = 2;
1452 		break;
1453 	default:
1454 		req_type = REQTYPE_DEVICE_TO_HOST;
1455 		len = 1;
1456 		break;
1457 	}
1458 
1459 	mask = 0;
1460 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1461 					  &mask, len);
1462 
1463 	usb_autopm_put_interface(serial->interface);
1464 
1465 	if (result < 0)
1466 		return result;
1467 
1468 	le16_to_cpus(&mask);
1469 
1470 	return !!(mask & BIT(gpio));
1471 }
1472 
1473 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1474 {
1475 	struct usb_serial *serial = gpiochip_get_data(gc);
1476 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1477 	struct cp210x_gpio_write16 buf16;
1478 	struct cp210x_gpio_write buf;
1479 	u16 mask, state;
1480 	u16 wIndex;
1481 	int result;
1482 
1483 	if (value == 1)
1484 		state = BIT(gpio);
1485 	else
1486 		state = 0;
1487 
1488 	mask = BIT(gpio);
1489 
1490 	result = usb_autopm_get_interface(serial->interface);
1491 	if (result)
1492 		goto out;
1493 
1494 	switch (priv->partnum) {
1495 	case CP210X_PARTNUM_CP2105:
1496 		buf.mask = (u8)mask;
1497 		buf.state = (u8)state;
1498 		result = cp210x_write_vendor_block(serial,
1499 						   REQTYPE_HOST_TO_INTERFACE,
1500 						   CP210X_WRITE_LATCH, &buf,
1501 						   sizeof(buf));
1502 		break;
1503 	case CP210X_PARTNUM_CP2108:
1504 		buf16.mask = cpu_to_le16(mask);
1505 		buf16.state = cpu_to_le16(state);
1506 		result = cp210x_write_vendor_block(serial,
1507 						   REQTYPE_HOST_TO_INTERFACE,
1508 						   CP210X_WRITE_LATCH, &buf16,
1509 						   sizeof(buf16));
1510 		break;
1511 	default:
1512 		wIndex = state << 8 | mask;
1513 		result = usb_control_msg(serial->dev,
1514 					 usb_sndctrlpipe(serial->dev, 0),
1515 					 CP210X_VENDOR_SPECIFIC,
1516 					 REQTYPE_HOST_TO_DEVICE,
1517 					 CP210X_WRITE_LATCH,
1518 					 wIndex,
1519 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1520 		break;
1521 	}
1522 
1523 	usb_autopm_put_interface(serial->interface);
1524 out:
1525 	if (result < 0) {
1526 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1527 				result);
1528 	}
1529 }
1530 
1531 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1532 {
1533 	struct usb_serial *serial = gpiochip_get_data(gc);
1534 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1535 
1536 	return priv->gpio_input & BIT(gpio);
1537 }
1538 
1539 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1540 {
1541 	struct usb_serial *serial = gpiochip_get_data(gc);
1542 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1543 
1544 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1545 		/* hardware does not support an input mode */
1546 		return -ENOTSUPP;
1547 	}
1548 
1549 	/* push-pull pins cannot be changed to be inputs */
1550 	if (priv->gpio_pushpull & BIT(gpio))
1551 		return -EINVAL;
1552 
1553 	/* make sure to release pin if it is being driven low */
1554 	cp210x_gpio_set(gc, gpio, 1);
1555 
1556 	priv->gpio_input |= BIT(gpio);
1557 
1558 	return 0;
1559 }
1560 
1561 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1562 					int value)
1563 {
1564 	struct usb_serial *serial = gpiochip_get_data(gc);
1565 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1566 
1567 	priv->gpio_input &= ~BIT(gpio);
1568 	cp210x_gpio_set(gc, gpio, value);
1569 
1570 	return 0;
1571 }
1572 
1573 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1574 				  unsigned long config)
1575 {
1576 	struct usb_serial *serial = gpiochip_get_data(gc);
1577 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1578 	enum pin_config_param param = pinconf_to_config_param(config);
1579 
1580 	/* Succeed only if in correct mode (this can't be set at runtime) */
1581 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1582 	    (priv->gpio_pushpull & BIT(gpio)))
1583 		return 0;
1584 
1585 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1586 	    !(priv->gpio_pushpull & BIT(gpio)))
1587 		return 0;
1588 
1589 	return -ENOTSUPP;
1590 }
1591 
1592 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1593 		unsigned long *valid_mask, unsigned int ngpios)
1594 {
1595 	struct usb_serial *serial = gpiochip_get_data(gc);
1596 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1597 	struct device *dev = &serial->interface->dev;
1598 	unsigned long altfunc_mask = priv->gpio_altfunc;
1599 
1600 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1601 
1602 	if (bitmap_empty(valid_mask, ngpios))
1603 		dev_dbg(dev, "no pin configured for GPIO\n");
1604 	else
1605 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1606 				valid_mask);
1607 	return 0;
1608 }
1609 
1610 /*
1611  * This function is for configuring GPIO using shared pins, where other signals
1612  * are made unavailable by configuring the use of GPIO. This is believed to be
1613  * only applicable to the cp2105 at this point, the other devices supported by
1614  * this driver that provide GPIO do so in a way that does not impact other
1615  * signals and are thus expected to have very different initialisation.
1616  */
1617 static int cp2105_gpioconf_init(struct usb_serial *serial)
1618 {
1619 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1620 	struct cp210x_pin_mode mode;
1621 	struct cp210x_dual_port_config config;
1622 	u8 intf_num = cp210x_interface_num(serial);
1623 	u8 iface_config;
1624 	int result;
1625 
1626 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1627 					  CP210X_GET_DEVICEMODE, &mode,
1628 					  sizeof(mode));
1629 	if (result < 0)
1630 		return result;
1631 
1632 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1633 					  CP210X_GET_PORTCONFIG, &config,
1634 					  sizeof(config));
1635 	if (result < 0)
1636 		return result;
1637 
1638 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1639 	if (intf_num == 0) {
1640 		priv->gc.ngpio = 2;
1641 
1642 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1643 			/* mark all GPIOs of this interface as reserved */
1644 			priv->gpio_altfunc = 0xff;
1645 			return 0;
1646 		}
1647 
1648 		iface_config = config.eci_cfg;
1649 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1650 						CP210X_ECI_GPIO_MODE_MASK) >>
1651 						CP210X_ECI_GPIO_MODE_OFFSET);
1652 	} else if (intf_num == 1) {
1653 		priv->gc.ngpio = 3;
1654 
1655 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1656 			/* mark all GPIOs of this interface as reserved */
1657 			priv->gpio_altfunc = 0xff;
1658 			return 0;
1659 		}
1660 
1661 		iface_config = config.sci_cfg;
1662 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1663 						CP210X_SCI_GPIO_MODE_MASK) >>
1664 						CP210X_SCI_GPIO_MODE_OFFSET);
1665 	} else {
1666 		return -ENODEV;
1667 	}
1668 
1669 	/* mark all pins which are not in GPIO mode */
1670 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1671 		priv->gpio_altfunc |= BIT(0);
1672 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1673 			CP2105_GPIO1_RS485_MODE))
1674 		priv->gpio_altfunc |= BIT(1);
1675 
1676 	/* driver implementation for CP2105 only supports outputs */
1677 	priv->gpio_input = 0;
1678 
1679 	return 0;
1680 }
1681 
1682 static int cp2104_gpioconf_init(struct usb_serial *serial)
1683 {
1684 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1685 	struct cp210x_single_port_config config;
1686 	u8 iface_config;
1687 	u8 gpio_latch;
1688 	int result;
1689 	u8 i;
1690 
1691 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1692 					  CP210X_GET_PORTCONFIG, &config,
1693 					  sizeof(config));
1694 	if (result < 0)
1695 		return result;
1696 
1697 	priv->gc.ngpio = 4;
1698 
1699 	iface_config = config.device_cfg;
1700 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1701 					CP210X_GPIO_MODE_MASK) >>
1702 					CP210X_GPIO_MODE_OFFSET);
1703 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1704 					CP210X_GPIO_MODE_MASK) >>
1705 					CP210X_GPIO_MODE_OFFSET);
1706 
1707 	/* mark all pins which are not in GPIO mode */
1708 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1709 		priv->gpio_altfunc |= BIT(0);
1710 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1711 		priv->gpio_altfunc |= BIT(1);
1712 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1713 		priv->gpio_altfunc |= BIT(2);
1714 
1715 	/*
1716 	 * Like CP2102N, CP2104 has also no strict input and output pin
1717 	 * modes.
1718 	 * Do the same input mode emulation as CP2102N.
1719 	 */
1720 	for (i = 0; i < priv->gc.ngpio; ++i) {
1721 		/*
1722 		 * Set direction to "input" iff pin is open-drain and reset
1723 		 * value is 1.
1724 		 */
1725 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1726 			priv->gpio_input |= BIT(i);
1727 	}
1728 
1729 	return 0;
1730 }
1731 
1732 static int cp2108_gpio_init(struct usb_serial *serial)
1733 {
1734 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1735 	struct cp210x_quad_port_config config;
1736 	u16 gpio_latch;
1737 	int result;
1738 	u8 i;
1739 
1740 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1741 					  CP210X_GET_PORTCONFIG, &config,
1742 					  sizeof(config));
1743 	if (result < 0)
1744 		return result;
1745 
1746 	priv->gc.ngpio = 16;
1747 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1748 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1749 
1750 	/*
1751 	 * Mark all pins which are not in GPIO mode.
1752 	 *
1753 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1754 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1755 	 *
1756 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1757 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1758 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1759 	 */
1760 	for (i = 0; i < 4; i++) {
1761 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1762 			priv->gpio_altfunc |= BIT(i * 4);
1763 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1764 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1765 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1766 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1767 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1768 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1769 	}
1770 
1771 	/*
1772 	 * Like CP2102N, CP2108 has also no strict input and output pin
1773 	 * modes. Do the same input mode emulation as CP2102N.
1774 	 */
1775 	for (i = 0; i < priv->gc.ngpio; ++i) {
1776 		/*
1777 		 * Set direction to "input" iff pin is open-drain and reset
1778 		 * value is 1.
1779 		 */
1780 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1781 			priv->gpio_input |= BIT(i);
1782 	}
1783 
1784 	return 0;
1785 }
1786 
1787 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1788 {
1789 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1790 	const u16 config_size = 0x02a6;
1791 	u8 gpio_rst_latch;
1792 	u8 config_version;
1793 	u8 gpio_pushpull;
1794 	u8 *config_buf;
1795 	u8 gpio_latch;
1796 	u8 gpio_ctrl;
1797 	int result;
1798 	u8 i;
1799 
1800 	/*
1801 	 * Retrieve device configuration from the device.
1802 	 * The array received contains all customization settings done at the
1803 	 * factory/manufacturer. Format of the array is documented at the
1804 	 * time of writing at:
1805 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1806 	 */
1807 	config_buf = kmalloc(config_size, GFP_KERNEL);
1808 	if (!config_buf)
1809 		return -ENOMEM;
1810 
1811 	result = cp210x_read_vendor_block(serial,
1812 					  REQTYPE_DEVICE_TO_HOST,
1813 					  CP210X_READ_2NCONFIG,
1814 					  config_buf,
1815 					  config_size);
1816 	if (result < 0) {
1817 		kfree(config_buf);
1818 		return result;
1819 	}
1820 
1821 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1822 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1823 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1824 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1825 
1826 	kfree(config_buf);
1827 
1828 	/* Make sure this is a config format we understand. */
1829 	if (config_version != 0x01)
1830 		return -ENOTSUPP;
1831 
1832 	priv->gc.ngpio = 4;
1833 
1834 	/*
1835 	 * Get default pin states after reset. Needed so we can determine
1836 	 * the direction of an open-drain pin.
1837 	 */
1838 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1839 
1840 	/* 0 indicates open-drain mode, 1 is push-pull */
1841 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1842 
1843 	/* 0 indicates GPIO mode, 1 is alternate function */
1844 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1845 		/* QFN20 is special... */
1846 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1847 			priv->gpio_altfunc |= BIT(0);
1848 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1849 			priv->gpio_altfunc |= BIT(1);
1850 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1851 			priv->gpio_altfunc |= BIT(2);
1852 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1853 			priv->gpio_altfunc |= BIT(3);
1854 	} else {
1855 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1856 	}
1857 
1858 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1859 		/*
1860 		 * For the QFN28 package, GPIO4-6 are controlled by
1861 		 * the low three bits of the mode/latch fields.
1862 		 * Contrary to the document linked above, the bits for
1863 		 * the SUSPEND pins are elsewhere.  No alternate
1864 		 * function is available for these pins.
1865 		 */
1866 		priv->gc.ngpio = 7;
1867 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1868 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1869 	}
1870 
1871 	/*
1872 	 * The CP2102N does not strictly has input and output pin modes,
1873 	 * it only knows open-drain and push-pull modes which is set at
1874 	 * factory. An open-drain pin can function both as an
1875 	 * input or an output. We emulate input mode for open-drain pins
1876 	 * by making sure they are not driven low, and we do not allow
1877 	 * push-pull pins to be set as an input.
1878 	 */
1879 	for (i = 0; i < priv->gc.ngpio; ++i) {
1880 		/*
1881 		 * Set direction to "input" iff pin is open-drain and reset
1882 		 * value is 1.
1883 		 */
1884 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1885 			priv->gpio_input |= BIT(i);
1886 	}
1887 
1888 	return 0;
1889 }
1890 
1891 static int cp210x_gpio_init(struct usb_serial *serial)
1892 {
1893 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1894 	int result;
1895 
1896 	switch (priv->partnum) {
1897 	case CP210X_PARTNUM_CP2104:
1898 		result = cp2104_gpioconf_init(serial);
1899 		break;
1900 	case CP210X_PARTNUM_CP2105:
1901 		result = cp2105_gpioconf_init(serial);
1902 		break;
1903 	case CP210X_PARTNUM_CP2108:
1904 		/*
1905 		 * The GPIOs are not tied to any specific port so only register
1906 		 * once for interface 0.
1907 		 */
1908 		if (cp210x_interface_num(serial) != 0)
1909 			return 0;
1910 		result = cp2108_gpio_init(serial);
1911 		break;
1912 	case CP210X_PARTNUM_CP2102N_QFN28:
1913 	case CP210X_PARTNUM_CP2102N_QFN24:
1914 	case CP210X_PARTNUM_CP2102N_QFN20:
1915 		result = cp2102n_gpioconf_init(serial);
1916 		break;
1917 	default:
1918 		return 0;
1919 	}
1920 
1921 	if (result < 0)
1922 		return result;
1923 
1924 	priv->gc.label = "cp210x";
1925 	priv->gc.get_direction = cp210x_gpio_direction_get;
1926 	priv->gc.direction_input = cp210x_gpio_direction_input;
1927 	priv->gc.direction_output = cp210x_gpio_direction_output;
1928 	priv->gc.get = cp210x_gpio_get;
1929 	priv->gc.set = cp210x_gpio_set;
1930 	priv->gc.set_config = cp210x_gpio_set_config;
1931 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1932 	priv->gc.owner = THIS_MODULE;
1933 	priv->gc.parent = &serial->interface->dev;
1934 	priv->gc.base = -1;
1935 	priv->gc.can_sleep = true;
1936 
1937 	result = gpiochip_add_data(&priv->gc, serial);
1938 	if (!result)
1939 		priv->gpio_registered = true;
1940 
1941 	return result;
1942 }
1943 
1944 static void cp210x_gpio_remove(struct usb_serial *serial)
1945 {
1946 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1947 
1948 	if (priv->gpio_registered) {
1949 		gpiochip_remove(&priv->gc);
1950 		priv->gpio_registered = false;
1951 	}
1952 }
1953 
1954 #else
1955 
1956 static int cp210x_gpio_init(struct usb_serial *serial)
1957 {
1958 	return 0;
1959 }
1960 
1961 static void cp210x_gpio_remove(struct usb_serial *serial)
1962 {
1963 	/* Nothing to do */
1964 }
1965 
1966 #endif
1967 
1968 static int cp210x_port_probe(struct usb_serial_port *port)
1969 {
1970 	struct usb_serial *serial = port->serial;
1971 	struct cp210x_port_private *port_priv;
1972 
1973 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1974 	if (!port_priv)
1975 		return -ENOMEM;
1976 
1977 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1978 	mutex_init(&port_priv->mutex);
1979 
1980 	usb_set_serial_port_data(port, port_priv);
1981 
1982 	return 0;
1983 }
1984 
1985 static void cp210x_port_remove(struct usb_serial_port *port)
1986 {
1987 	struct cp210x_port_private *port_priv;
1988 
1989 	port_priv = usb_get_serial_port_data(port);
1990 	kfree(port_priv);
1991 }
1992 
1993 static void cp210x_init_max_speed(struct usb_serial *serial)
1994 {
1995 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1996 	bool use_actual_rate = false;
1997 	speed_t min = 300;
1998 	speed_t max;
1999 
2000 	switch (priv->partnum) {
2001 	case CP210X_PARTNUM_CP2101:
2002 		max = 921600;
2003 		break;
2004 	case CP210X_PARTNUM_CP2102:
2005 	case CP210X_PARTNUM_CP2103:
2006 		max = 1000000;
2007 		break;
2008 	case CP210X_PARTNUM_CP2104:
2009 		use_actual_rate = true;
2010 		max = 2000000;
2011 		break;
2012 	case CP210X_PARTNUM_CP2108:
2013 		max = 2000000;
2014 		break;
2015 	case CP210X_PARTNUM_CP2105:
2016 		if (cp210x_interface_num(serial) == 0) {
2017 			use_actual_rate = true;
2018 			max = 2000000;	/* ECI */
2019 		} else {
2020 			min = 2400;
2021 			max = 921600;	/* SCI */
2022 		}
2023 		break;
2024 	case CP210X_PARTNUM_CP2102N_QFN28:
2025 	case CP210X_PARTNUM_CP2102N_QFN24:
2026 	case CP210X_PARTNUM_CP2102N_QFN20:
2027 		use_actual_rate = true;
2028 		max = 3000000;
2029 		break;
2030 	default:
2031 		max = 2000000;
2032 		break;
2033 	}
2034 
2035 	priv->min_speed = min;
2036 	priv->max_speed = max;
2037 	priv->use_actual_rate = use_actual_rate;
2038 }
2039 
2040 static void cp2102_determine_quirks(struct usb_serial *serial)
2041 {
2042 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2043 	u8 *buf;
2044 	int ret;
2045 
2046 	buf = kmalloc(2, GFP_KERNEL);
2047 	if (!buf)
2048 		return;
2049 	/*
2050 	 * Some (possibly counterfeit) CP2102 do not support event-insertion
2051 	 * mode and respond differently to malformed vendor requests.
2052 	 * Specifically, they return one instead of two bytes when sent a
2053 	 * two-byte part-number request.
2054 	 */
2055 	ret = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2056 			CP210X_VENDOR_SPECIFIC, REQTYPE_DEVICE_TO_HOST,
2057 			CP210X_GET_PARTNUM, 0, buf, 2, USB_CTRL_GET_TIMEOUT);
2058 	if (ret == 1) {
2059 		dev_dbg(&serial->interface->dev,
2060 				"device does not support event-insertion mode\n");
2061 		priv->no_event_mode = true;
2062 	}
2063 
2064 	kfree(buf);
2065 }
2066 
2067 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2068 {
2069 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2070 	u8 ver[3];
2071 	int ret;
2072 
2073 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2074 			ver, sizeof(ver));
2075 	if (ret)
2076 		return ret;
2077 
2078 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2079 			ver[0], ver[1], ver[2]);
2080 
2081 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2082 
2083 	return 0;
2084 }
2085 
2086 static void cp210x_determine_type(struct usb_serial *serial)
2087 {
2088 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2089 	int ret;
2090 
2091 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2092 			CP210X_GET_PARTNUM, &priv->partnum,
2093 			sizeof(priv->partnum));
2094 	if (ret < 0) {
2095 		dev_warn(&serial->interface->dev,
2096 				"querying part number failed\n");
2097 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2098 		return;
2099 	}
2100 
2101 	dev_dbg(&serial->interface->dev, "partnum = 0x%02x\n", priv->partnum);
2102 
2103 	switch (priv->partnum) {
2104 	case CP210X_PARTNUM_CP2102:
2105 		cp2102_determine_quirks(serial);
2106 		break;
2107 	case CP210X_PARTNUM_CP2105:
2108 	case CP210X_PARTNUM_CP2108:
2109 		cp210x_get_fw_version(serial, CP210X_GET_FW_VER);
2110 		break;
2111 	case CP210X_PARTNUM_CP2102N_QFN28:
2112 	case CP210X_PARTNUM_CP2102N_QFN24:
2113 	case CP210X_PARTNUM_CP2102N_QFN20:
2114 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2115 		if (ret)
2116 			break;
2117 		if (priv->fw_version <= 0x10004)
2118 			priv->no_flow_control = true;
2119 		break;
2120 	default:
2121 		break;
2122 	}
2123 }
2124 
2125 static int cp210x_attach(struct usb_serial *serial)
2126 {
2127 	int result;
2128 	struct cp210x_serial_private *priv;
2129 
2130 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2131 	if (!priv)
2132 		return -ENOMEM;
2133 
2134 	usb_set_serial_data(serial, priv);
2135 
2136 	cp210x_determine_type(serial);
2137 	cp210x_init_max_speed(serial);
2138 
2139 	result = cp210x_gpio_init(serial);
2140 	if (result < 0) {
2141 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2142 				result);
2143 	}
2144 
2145 	return 0;
2146 }
2147 
2148 static void cp210x_disconnect(struct usb_serial *serial)
2149 {
2150 	cp210x_gpio_remove(serial);
2151 }
2152 
2153 static void cp210x_release(struct usb_serial *serial)
2154 {
2155 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2156 
2157 	cp210x_gpio_remove(serial);
2158 
2159 	kfree(priv);
2160 }
2161 
2162 module_usb_serial_driver(serial_drivers, id_table);
2163 
2164 MODULE_DESCRIPTION(DRIVER_DESC);
2165 MODULE_LICENSE("GPL v2");
2166