xref: /linux/drivers/usb/serial/cp210x.c (revision a0d9d868491a362d421521499d98308c8e3a0398)
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 				const struct ktermios *);
35 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
36 			       const 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 int 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, 0x0070) }, /* Siemens SCALANCE LPE-9000 USB Serial Console */
64 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
65 	{ USB_DEVICE(0x0988, 0x0578) }, /* Teraoka AD2000 */
66 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
67 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
68 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
69 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
71 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
72 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
73 	{ USB_DEVICE(0x106F, 0x0003) },	/* CPI / Money Controls Bulk Coin Recycler */
74 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
75 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
76 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
77 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
78 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
79 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
80 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
81 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
82 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
83 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
84 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
85 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
86 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
87 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
88 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
89 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
90 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
91 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
92 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
93 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
94 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
95 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
96 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
97 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
98 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
99 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
100 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
101 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
102 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
103 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
104 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
105 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
106 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
107 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
108 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
109 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
110 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
111 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
112 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
113 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
114 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
115 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
116 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
117 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
118 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
119 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
120 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
121 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
122 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
123 	{ USB_DEVICE(0x10C4, 0x82AA) }, /* Silicon Labs IFS-USB-DATACABLE used with Quint UPS */
124 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
125 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
126 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
127 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
128 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
129 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
130 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
131 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
132 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
133 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
134 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
135 	{ USB_DEVICE(0x10C4, 0x8414) }, /* Decagon USB Cable Adapter */
136 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
137 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
138 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
139 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
140 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
141 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
142 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
143 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
144 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
145 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
146 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
147 	{ USB_DEVICE(0x10C4, 0x863C) }, /* MGP Instruments PDS100 */
148 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
149 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
150 	{ USB_DEVICE(0x10C4, 0x87ED) }, /* IMST USB-Stick for Smart Meter */
151 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
152 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
153 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
154 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
155 	{ USB_DEVICE(0x10C4, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
156 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
157 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
158 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
159 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
160 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
161 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
162 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
163 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
164 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
165 	{ USB_DEVICE(0x10C4, 0x8A5B) }, /* CEL EM3588 ZigBee USB Stick */
166 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
167 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
168 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
169 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
170 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
171 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
172 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
173 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
174 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
175 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
176 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
177 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
178 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
179 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
180 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
181 	{ USB_DEVICE(0x11CA, 0x0212) }, /* Verifone USB to Printer (UART, CP2102) */
182 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
183 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
184 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
185 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
186 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
187 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
188 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
189 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
190 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
191 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
192 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
193 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
194 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
195 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
196 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
197 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
198 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
199 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
200 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
201 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
202 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
203 	{ USB_DEVICE(0x17A8, 0x0011) }, /* Kamstrup 444 MHz RF sniffer */
204 	{ USB_DEVICE(0x17A8, 0x0013) }, /* Kamstrup 870 MHz RF sniffer */
205 	{ USB_DEVICE(0x17A8, 0x0101) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Int Ant) */
206 	{ USB_DEVICE(0x17A8, 0x0102) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Ext Ant) */
207 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
208 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
209 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
210 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
211 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
212 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
213 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
214 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
215 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
216 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
217 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
218 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 M.2 Key E serial interface */
219 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 Display serial interface */
220 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
221 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
222 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
223 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
224 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
225 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
226 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
227 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
228 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
229 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
230 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
231 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
232 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
233 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
234 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
235 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
236 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
237 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
238 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
239 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
240 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
241 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
242 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
243 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
244 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
245 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
246 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
247 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
248 	{ USB_DEVICE(0x2184, 0x0030) }, /* GW Instek GDM-834x Digital Multimeter */
249 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
250 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
251 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
252 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
253 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
254 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
255 	{ } /* Terminating Entry */
256 };
257 
258 MODULE_DEVICE_TABLE(usb, id_table);
259 
260 struct cp210x_serial_private {
261 #ifdef CONFIG_GPIOLIB
262 	struct gpio_chip	gc;
263 	bool			gpio_registered;
264 	u16			gpio_pushpull;
265 	u16			gpio_altfunc;
266 	u16			gpio_input;
267 #endif
268 	u8			partnum;
269 	u32			fw_version;
270 	speed_t			min_speed;
271 	speed_t			max_speed;
272 	bool			use_actual_rate;
273 	bool			no_flow_control;
274 	bool			no_event_mode;
275 };
276 
277 enum cp210x_event_state {
278 	ES_DATA,
279 	ES_ESCAPE,
280 	ES_LSR,
281 	ES_LSR_DATA_0,
282 	ES_LSR_DATA_1,
283 	ES_MSR
284 };
285 
286 struct cp210x_port_private {
287 	u8			bInterfaceNumber;
288 	bool			event_mode;
289 	enum cp210x_event_state event_state;
290 	u8			lsr;
291 
292 	struct mutex		mutex;
293 	bool			crtscts;
294 	bool			dtr;
295 	bool			rts;
296 };
297 
298 static struct usb_serial_driver cp210x_device = {
299 	.driver = {
300 		.owner =	THIS_MODULE,
301 		.name =		"cp210x",
302 	},
303 	.id_table		= id_table,
304 	.num_ports		= 1,
305 	.bulk_in_size		= 256,
306 	.bulk_out_size		= 256,
307 	.open			= cp210x_open,
308 	.close			= cp210x_close,
309 	.break_ctl		= cp210x_break_ctl,
310 	.set_termios		= cp210x_set_termios,
311 	.tx_empty		= cp210x_tx_empty,
312 	.throttle		= usb_serial_generic_throttle,
313 	.unthrottle		= usb_serial_generic_unthrottle,
314 	.tiocmget		= cp210x_tiocmget,
315 	.tiocmset		= cp210x_tiocmset,
316 	.get_icount		= usb_serial_generic_get_icount,
317 	.attach			= cp210x_attach,
318 	.disconnect		= cp210x_disconnect,
319 	.release		= cp210x_release,
320 	.port_probe		= cp210x_port_probe,
321 	.port_remove		= cp210x_port_remove,
322 	.dtr_rts		= cp210x_dtr_rts,
323 	.process_read_urb	= cp210x_process_read_urb,
324 };
325 
326 static struct usb_serial_driver * const serial_drivers[] = {
327 	&cp210x_device, NULL
328 };
329 
330 /* Config request types */
331 #define REQTYPE_HOST_TO_INTERFACE	0x41
332 #define REQTYPE_INTERFACE_TO_HOST	0xc1
333 #define REQTYPE_HOST_TO_DEVICE	0x40
334 #define REQTYPE_DEVICE_TO_HOST	0xc0
335 
336 /* Config request codes */
337 #define CP210X_IFC_ENABLE	0x00
338 #define CP210X_SET_BAUDDIV	0x01
339 #define CP210X_GET_BAUDDIV	0x02
340 #define CP210X_SET_LINE_CTL	0x03
341 #define CP210X_GET_LINE_CTL	0x04
342 #define CP210X_SET_BREAK	0x05
343 #define CP210X_IMM_CHAR		0x06
344 #define CP210X_SET_MHS		0x07
345 #define CP210X_GET_MDMSTS	0x08
346 #define CP210X_SET_XON		0x09
347 #define CP210X_SET_XOFF		0x0A
348 #define CP210X_SET_EVENTMASK	0x0B
349 #define CP210X_GET_EVENTMASK	0x0C
350 #define CP210X_SET_CHAR		0x0D
351 #define CP210X_GET_CHARS	0x0E
352 #define CP210X_GET_PROPS	0x0F
353 #define CP210X_GET_COMM_STATUS	0x10
354 #define CP210X_RESET		0x11
355 #define CP210X_PURGE		0x12
356 #define CP210X_SET_FLOW		0x13
357 #define CP210X_GET_FLOW		0x14
358 #define CP210X_EMBED_EVENTS	0x15
359 #define CP210X_GET_EVENTSTATE	0x16
360 #define CP210X_SET_CHARS	0x19
361 #define CP210X_GET_BAUDRATE	0x1D
362 #define CP210X_SET_BAUDRATE	0x1E
363 #define CP210X_VENDOR_SPECIFIC	0xFF
364 
365 /* CP210X_IFC_ENABLE */
366 #define UART_ENABLE		0x0001
367 #define UART_DISABLE		0x0000
368 
369 /* CP210X_(SET|GET)_BAUDDIV */
370 #define BAUD_RATE_GEN_FREQ	0x384000
371 
372 /* CP210X_(SET|GET)_LINE_CTL */
373 #define BITS_DATA_MASK		0X0f00
374 #define BITS_DATA_5		0X0500
375 #define BITS_DATA_6		0X0600
376 #define BITS_DATA_7		0X0700
377 #define BITS_DATA_8		0X0800
378 #define BITS_DATA_9		0X0900
379 
380 #define BITS_PARITY_MASK	0x00f0
381 #define BITS_PARITY_NONE	0x0000
382 #define BITS_PARITY_ODD		0x0010
383 #define BITS_PARITY_EVEN	0x0020
384 #define BITS_PARITY_MARK	0x0030
385 #define BITS_PARITY_SPACE	0x0040
386 
387 #define BITS_STOP_MASK		0x000f
388 #define BITS_STOP_1		0x0000
389 #define BITS_STOP_1_5		0x0001
390 #define BITS_STOP_2		0x0002
391 
392 /* CP210X_SET_BREAK */
393 #define BREAK_ON		0x0001
394 #define BREAK_OFF		0x0000
395 
396 /* CP210X_(SET_MHS|GET_MDMSTS) */
397 #define CONTROL_DTR		0x0001
398 #define CONTROL_RTS		0x0002
399 #define CONTROL_CTS		0x0010
400 #define CONTROL_DSR		0x0020
401 #define CONTROL_RING		0x0040
402 #define CONTROL_DCD		0x0080
403 #define CONTROL_WRITE_DTR	0x0100
404 #define CONTROL_WRITE_RTS	0x0200
405 
406 /* CP210X_(GET|SET)_CHARS */
407 struct cp210x_special_chars {
408 	u8	bEofChar;
409 	u8	bErrorChar;
410 	u8	bBreakChar;
411 	u8	bEventChar;
412 	u8	bXonChar;
413 	u8	bXoffChar;
414 };
415 
416 /* CP210X_VENDOR_SPECIFIC values */
417 #define CP210X_GET_FW_VER	0x000E
418 #define CP210X_READ_2NCONFIG	0x000E
419 #define CP210X_GET_FW_VER_2N	0x0010
420 #define CP210X_READ_LATCH	0x00C2
421 #define CP210X_GET_PARTNUM	0x370B
422 #define CP210X_GET_PORTCONFIG	0x370C
423 #define CP210X_GET_DEVICEMODE	0x3711
424 #define CP210X_WRITE_LATCH	0x37E1
425 
426 /* Part number definitions */
427 #define CP210X_PARTNUM_CP2101	0x01
428 #define CP210X_PARTNUM_CP2102	0x02
429 #define CP210X_PARTNUM_CP2103	0x03
430 #define CP210X_PARTNUM_CP2104	0x04
431 #define CP210X_PARTNUM_CP2105	0x05
432 #define CP210X_PARTNUM_CP2108	0x08
433 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
434 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
435 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
436 #define CP210X_PARTNUM_UNKNOWN	0xFF
437 
438 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
439 struct cp210x_comm_status {
440 	__le32   ulErrors;
441 	__le32   ulHoldReasons;
442 	__le32   ulAmountInInQueue;
443 	__le32   ulAmountInOutQueue;
444 	u8       bEofReceived;
445 	u8       bWaitForImmediate;
446 	u8       bReserved;
447 } __packed;
448 
449 /*
450  * CP210X_PURGE - 16 bits passed in wValue of USB request.
451  * SiLabs app note AN571 gives a strange description of the 4 bits:
452  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
453  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
454  */
455 #define PURGE_ALL		0x000f
456 
457 /* CP210X_EMBED_EVENTS */
458 #define CP210X_ESCCHAR		0xec
459 
460 #define CP210X_LSR_OVERRUN	BIT(1)
461 #define CP210X_LSR_PARITY	BIT(2)
462 #define CP210X_LSR_FRAME	BIT(3)
463 #define CP210X_LSR_BREAK	BIT(4)
464 
465 
466 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
467 struct cp210x_flow_ctl {
468 	__le32	ulControlHandshake;
469 	__le32	ulFlowReplace;
470 	__le32	ulXonLimit;
471 	__le32	ulXoffLimit;
472 };
473 
474 /* cp210x_flow_ctl::ulControlHandshake */
475 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
476 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
477 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
478 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
479 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
480 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
481 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
482 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
483 
484 /* cp210x_flow_ctl::ulFlowReplace */
485 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
486 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
487 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
488 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
489 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
490 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
491 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
492 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
493 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
494 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
495 
496 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
497 struct cp210x_pin_mode {
498 	u8	eci;
499 	u8	sci;
500 };
501 
502 #define CP210X_PIN_MODE_MODEM		0
503 #define CP210X_PIN_MODE_GPIO		BIT(0)
504 
505 /*
506  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
507  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
508  */
509 struct cp210x_dual_port_config {
510 	__le16	gpio_mode;
511 	u8	__pad0[2];
512 	__le16	reset_state;
513 	u8	__pad1[4];
514 	__le16	suspend_state;
515 	u8	sci_cfg;
516 	u8	eci_cfg;
517 	u8	device_cfg;
518 } __packed;
519 
520 /*
521  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
522  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
523  */
524 struct cp210x_single_port_config {
525 	__le16	gpio_mode;
526 	u8	__pad0[2];
527 	__le16	reset_state;
528 	u8	__pad1[4];
529 	__le16	suspend_state;
530 	u8	device_cfg;
531 } __packed;
532 
533 /* GPIO modes */
534 #define CP210X_SCI_GPIO_MODE_OFFSET	9
535 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
536 
537 #define CP210X_ECI_GPIO_MODE_OFFSET	2
538 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
539 
540 #define CP210X_GPIO_MODE_OFFSET		8
541 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
542 
543 /* CP2105 port configuration values */
544 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
545 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
546 #define CP2105_GPIO1_RS485_MODE		BIT(2)
547 
548 /* CP2104 port configuration values */
549 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
550 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
551 #define CP2104_GPIO2_RS485_MODE		BIT(2)
552 
553 struct cp210x_quad_port_state {
554 	__le16 gpio_mode_pb0;
555 	__le16 gpio_mode_pb1;
556 	__le16 gpio_mode_pb2;
557 	__le16 gpio_mode_pb3;
558 	__le16 gpio_mode_pb4;
559 
560 	__le16 gpio_lowpower_pb0;
561 	__le16 gpio_lowpower_pb1;
562 	__le16 gpio_lowpower_pb2;
563 	__le16 gpio_lowpower_pb3;
564 	__le16 gpio_lowpower_pb4;
565 
566 	__le16 gpio_latch_pb0;
567 	__le16 gpio_latch_pb1;
568 	__le16 gpio_latch_pb2;
569 	__le16 gpio_latch_pb3;
570 	__le16 gpio_latch_pb4;
571 };
572 
573 /*
574  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
575  * on a CP2108 chip.
576  *
577  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
578  */
579 struct cp210x_quad_port_config {
580 	struct cp210x_quad_port_state reset_state;
581 	struct cp210x_quad_port_state suspend_state;
582 	u8 ipdelay_ifc[4];
583 	u8 enhancedfxn_ifc[4];
584 	u8 enhancedfxn_device;
585 	u8 extclkfreq[4];
586 } __packed;
587 
588 #define CP2108_EF_IFC_GPIO_TXLED		0x01
589 #define CP2108_EF_IFC_GPIO_RXLED		0x02
590 #define CP2108_EF_IFC_GPIO_RS485		0x04
591 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
592 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
593 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
594 
595 /* CP2102N configuration array indices */
596 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
597 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
598 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
599 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
600 
601 /* CP2102N QFN20 port configuration values */
602 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
603 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
604 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
605 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
606 
607 /*
608  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
609  * for CP2102N, CP2103, CP2104 and CP2105.
610  */
611 struct cp210x_gpio_write {
612 	u8	mask;
613 	u8	state;
614 };
615 
616 /*
617  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
618  * for CP2108.
619  */
620 struct cp210x_gpio_write16 {
621 	__le16	mask;
622 	__le16	state;
623 };
624 
625 /*
626  * Helper to get interface number when we only have struct usb_serial.
627  */
628 static u8 cp210x_interface_num(struct usb_serial *serial)
629 {
630 	struct usb_host_interface *cur_altsetting;
631 
632 	cur_altsetting = serial->interface->cur_altsetting;
633 
634 	return cur_altsetting->desc.bInterfaceNumber;
635 }
636 
637 /*
638  * Reads a variable-sized block of CP210X_ registers, identified by req.
639  * Returns data into buf in native USB byte order.
640  */
641 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
642 		void *buf, int bufsize)
643 {
644 	struct usb_serial *serial = port->serial;
645 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
646 	int result;
647 
648 
649 	result = usb_control_msg_recv(serial->dev, 0, req,
650 			REQTYPE_INTERFACE_TO_HOST, 0,
651 			port_priv->bInterfaceNumber, buf, bufsize,
652 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
653 	if (result) {
654 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
655 				req, bufsize, result);
656 		return result;
657 	}
658 
659 	return 0;
660 }
661 
662 /*
663  * Reads any 8-bit CP210X_ register identified by req.
664  */
665 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
666 {
667 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
668 }
669 
670 /*
671  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
672  * Returns data into buf in native USB byte order.
673  */
674 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
675 				    void *buf, int bufsize)
676 {
677 	int result;
678 
679 	result = usb_control_msg_recv(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
680 			type, val, cp210x_interface_num(serial), buf, bufsize,
681 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
682 	if (result) {
683 		dev_err(&serial->interface->dev,
684 			"failed to get vendor val 0x%04x size %d: %d\n", val,
685 			bufsize, result);
686 		return result;
687 	}
688 
689 	return 0;
690 }
691 
692 /*
693  * Writes any 16-bit CP210X_ register (req) whose value is passed
694  * entirely in the wValue field of the USB request.
695  */
696 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
697 {
698 	struct usb_serial *serial = port->serial;
699 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
700 	int result;
701 
702 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
703 			req, REQTYPE_HOST_TO_INTERFACE, val,
704 			port_priv->bInterfaceNumber, NULL, 0,
705 			USB_CTRL_SET_TIMEOUT);
706 	if (result < 0) {
707 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
708 				req, result);
709 	}
710 
711 	return result;
712 }
713 
714 /*
715  * Writes a variable-sized block of CP210X_ registers, identified by req.
716  * Data in buf must be in native USB byte order.
717  */
718 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
719 		void *buf, int bufsize)
720 {
721 	struct usb_serial *serial = port->serial;
722 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
723 	int result;
724 
725 	result = usb_control_msg_send(serial->dev, 0, req,
726 			REQTYPE_HOST_TO_INTERFACE, 0,
727 			port_priv->bInterfaceNumber, buf, bufsize,
728 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
729 	if (result) {
730 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
731 				req, bufsize, result);
732 		return result;
733 	}
734 
735 	return 0;
736 }
737 
738 /*
739  * Writes any 32-bit CP210X_ register identified by req.
740  */
741 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
742 {
743 	__le32 le32_val;
744 
745 	le32_val = cpu_to_le32(val);
746 
747 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
748 }
749 
750 #ifdef CONFIG_GPIOLIB
751 /*
752  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
753  * Data in buf must be in native USB byte order.
754  */
755 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
756 				     u16 val, void *buf, int bufsize)
757 {
758 	int result;
759 
760 	result = usb_control_msg_send(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
761 			type, val, cp210x_interface_num(serial), buf, bufsize,
762 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
763 	if (result) {
764 		dev_err(&serial->interface->dev,
765 			"failed to set vendor val 0x%04x size %d: %d\n", val,
766 			bufsize, result);
767 		return result;
768 	}
769 
770 	return 0;
771 }
772 #endif
773 
774 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
775 {
776 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
777 	int result;
778 
779 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
780 	if (result) {
781 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
782 		return result;
783 	}
784 
785 	if (tty)
786 		cp210x_set_termios(tty, port, NULL);
787 
788 	result = usb_serial_generic_open(tty, port);
789 	if (result)
790 		goto err_disable;
791 
792 	return 0;
793 
794 err_disable:
795 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
796 	port_priv->event_mode = false;
797 
798 	return result;
799 }
800 
801 static void cp210x_close(struct usb_serial_port *port)
802 {
803 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
804 
805 	usb_serial_generic_close(port);
806 
807 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
808 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
809 
810 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
811 
812 	/* Disabling the interface disables event-insertion mode. */
813 	port_priv->event_mode = false;
814 }
815 
816 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
817 {
818 	if (lsr & CP210X_LSR_BREAK) {
819 		port->icount.brk++;
820 		*flag = TTY_BREAK;
821 	} else if (lsr & CP210X_LSR_PARITY) {
822 		port->icount.parity++;
823 		*flag = TTY_PARITY;
824 	} else if (lsr & CP210X_LSR_FRAME) {
825 		port->icount.frame++;
826 		*flag = TTY_FRAME;
827 	}
828 
829 	if (lsr & CP210X_LSR_OVERRUN) {
830 		port->icount.overrun++;
831 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
832 	}
833 }
834 
835 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
836 {
837 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
838 
839 	switch (port_priv->event_state) {
840 	case ES_DATA:
841 		if (*ch == CP210X_ESCCHAR) {
842 			port_priv->event_state = ES_ESCAPE;
843 			break;
844 		}
845 		return false;
846 	case ES_ESCAPE:
847 		switch (*ch) {
848 		case 0:
849 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
850 			*ch = CP210X_ESCCHAR;
851 			port_priv->event_state = ES_DATA;
852 			return false;
853 		case 1:
854 			port_priv->event_state = ES_LSR_DATA_0;
855 			break;
856 		case 2:
857 			port_priv->event_state = ES_LSR;
858 			break;
859 		case 3:
860 			port_priv->event_state = ES_MSR;
861 			break;
862 		default:
863 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
864 			port_priv->event_state = ES_DATA;
865 			break;
866 		}
867 		break;
868 	case ES_LSR_DATA_0:
869 		port_priv->lsr = *ch;
870 		port_priv->event_state = ES_LSR_DATA_1;
871 		break;
872 	case ES_LSR_DATA_1:
873 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
874 				__func__, port_priv->lsr, *ch);
875 		cp210x_process_lsr(port, port_priv->lsr, flag);
876 		port_priv->event_state = ES_DATA;
877 		return false;
878 	case ES_LSR:
879 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
880 		port_priv->lsr = *ch;
881 		cp210x_process_lsr(port, port_priv->lsr, flag);
882 		port_priv->event_state = ES_DATA;
883 		break;
884 	case ES_MSR:
885 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
886 		/* unimplemented */
887 		port_priv->event_state = ES_DATA;
888 		break;
889 	}
890 
891 	return true;
892 }
893 
894 static void cp210x_process_read_urb(struct urb *urb)
895 {
896 	struct usb_serial_port *port = urb->context;
897 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
898 	unsigned char *ch = urb->transfer_buffer;
899 	char flag;
900 	int i;
901 
902 	if (!urb->actual_length)
903 		return;
904 
905 	if (port_priv->event_mode) {
906 		for (i = 0; i < urb->actual_length; i++, ch++) {
907 			flag = TTY_NORMAL;
908 
909 			if (cp210x_process_char(port, ch, &flag))
910 				continue;
911 
912 			tty_insert_flip_char(&port->port, *ch, flag);
913 		}
914 	} else {
915 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
916 	}
917 	tty_flip_buffer_push(&port->port);
918 }
919 
920 /*
921  * Read how many bytes are waiting in the TX queue.
922  */
923 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
924 		u32 *count)
925 {
926 	struct usb_serial *serial = port->serial;
927 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
928 	struct cp210x_comm_status sts;
929 	int result;
930 
931 	result = usb_control_msg_recv(serial->dev, 0, CP210X_GET_COMM_STATUS,
932 			REQTYPE_INTERFACE_TO_HOST, 0,
933 			port_priv->bInterfaceNumber, &sts, sizeof(sts),
934 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
935 	if (result) {
936 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
937 		return result;
938 	}
939 
940 	*count = le32_to_cpu(sts.ulAmountInOutQueue);
941 
942 	return 0;
943 }
944 
945 static bool cp210x_tx_empty(struct usb_serial_port *port)
946 {
947 	int err;
948 	u32 count;
949 
950 	err = cp210x_get_tx_queue_byte_count(port, &count);
951 	if (err)
952 		return true;
953 
954 	return !count;
955 }
956 
957 struct cp210x_rate {
958 	speed_t rate;
959 	speed_t high;
960 };
961 
962 static const struct cp210x_rate cp210x_an205_table1[] = {
963 	{ 300, 300 },
964 	{ 600, 600 },
965 	{ 1200, 1200 },
966 	{ 1800, 1800 },
967 	{ 2400, 2400 },
968 	{ 4000, 4000 },
969 	{ 4800, 4803 },
970 	{ 7200, 7207 },
971 	{ 9600, 9612 },
972 	{ 14400, 14428 },
973 	{ 16000, 16062 },
974 	{ 19200, 19250 },
975 	{ 28800, 28912 },
976 	{ 38400, 38601 },
977 	{ 51200, 51558 },
978 	{ 56000, 56280 },
979 	{ 57600, 58053 },
980 	{ 64000, 64111 },
981 	{ 76800, 77608 },
982 	{ 115200, 117028 },
983 	{ 128000, 129347 },
984 	{ 153600, 156868 },
985 	{ 230400, 237832 },
986 	{ 250000, 254234 },
987 	{ 256000, 273066 },
988 	{ 460800, 491520 },
989 	{ 500000, 567138 },
990 	{ 576000, 670254 },
991 	{ 921600, UINT_MAX }
992 };
993 
994 /*
995  * Quantises the baud rate as per AN205 Table 1
996  */
997 static speed_t cp210x_get_an205_rate(speed_t baud)
998 {
999 	int i;
1000 
1001 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1002 		if (baud <= cp210x_an205_table1[i].high)
1003 			break;
1004 	}
1005 
1006 	return cp210x_an205_table1[i].rate;
1007 }
1008 
1009 static speed_t cp210x_get_actual_rate(speed_t baud)
1010 {
1011 	unsigned int prescale = 1;
1012 	unsigned int div;
1013 
1014 	if (baud <= 365)
1015 		prescale = 4;
1016 
1017 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1018 	baud = 48000000 / (2 * prescale * div);
1019 
1020 	return baud;
1021 }
1022 
1023 /*
1024  * CP2101 supports the following baud rates:
1025  *
1026  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1027  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1028  *
1029  * CP2102 and CP2103 support the following additional rates:
1030  *
1031  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1032  *	576000
1033  *
1034  * The device will map a requested rate to a supported one, but the result
1035  * of requests for rates greater than 1053257 is undefined (see AN205).
1036  *
1037  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1038  * respectively, with an error less than 1%. The actual rates are determined
1039  * by
1040  *
1041  *	div = round(freq / (2 x prescale x request))
1042  *	actual = freq / (2 x prescale x div)
1043  *
1044  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1045  * or 1 otherwise.
1046  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1047  * otherwise.
1048  */
1049 static void cp210x_change_speed(struct tty_struct *tty,
1050 				struct usb_serial_port *port,
1051 				const struct ktermios *old_termios)
1052 {
1053 	struct usb_serial *serial = port->serial;
1054 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1055 	u32 baud;
1056 
1057 	if (tty->termios.c_ospeed == 0)
1058 		return;
1059 
1060 	/*
1061 	 * This maps the requested rate to the actual rate, a valid rate on
1062 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1063 	 */
1064 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1065 
1066 	if (priv->use_actual_rate)
1067 		baud = cp210x_get_actual_rate(baud);
1068 	else if (baud < 1000000)
1069 		baud = cp210x_get_an205_rate(baud);
1070 
1071 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1072 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1073 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1074 		if (old_termios)
1075 			baud = old_termios->c_ospeed;
1076 		else
1077 			baud = 9600;
1078 	}
1079 
1080 	tty_encode_baud_rate(tty, baud, baud);
1081 }
1082 
1083 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1084 {
1085 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1086 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1087 	int ret;
1088 
1089 	if (port_priv->event_mode)
1090 		return;
1091 
1092 	if (priv->no_event_mode)
1093 		return;
1094 
1095 	port_priv->event_state = ES_DATA;
1096 	port_priv->event_mode = true;
1097 
1098 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1099 	if (ret) {
1100 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1101 		port_priv->event_mode = false;
1102 	}
1103 }
1104 
1105 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1106 {
1107 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1108 	int ret;
1109 
1110 	if (!port_priv->event_mode)
1111 		return;
1112 
1113 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1114 	if (ret) {
1115 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1116 		return;
1117 	}
1118 
1119 	port_priv->event_mode = false;
1120 }
1121 
1122 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1123 {
1124 	bool iflag_change, cc_change;
1125 
1126 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1127 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1128 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1129 
1130 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1131 }
1132 
1133 static void cp210x_set_flow_control(struct tty_struct *tty,
1134 				    struct usb_serial_port *port,
1135 				    const struct ktermios *old_termios)
1136 {
1137 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1138 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1139 	struct cp210x_special_chars chars;
1140 	struct cp210x_flow_ctl flow_ctl;
1141 	u32 flow_repl;
1142 	u32 ctl_hs;
1143 	bool crtscts;
1144 	int ret;
1145 
1146 	/*
1147 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1148 	 * CP2102N_E104). Report back that flow control is not supported.
1149 	 */
1150 	if (priv->no_flow_control) {
1151 		tty->termios.c_cflag &= ~CRTSCTS;
1152 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1153 	}
1154 
1155 	if (tty->termios.c_ospeed != 0 &&
1156 			old_termios && old_termios->c_ospeed != 0 &&
1157 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1158 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1159 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1160 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1161 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1162 		return;
1163 	}
1164 
1165 	if (I_IXON(tty) || I_IXOFF(tty)) {
1166 		memset(&chars, 0, sizeof(chars));
1167 
1168 		chars.bXonChar = START_CHAR(tty);
1169 		chars.bXoffChar = STOP_CHAR(tty);
1170 
1171 		ret = cp210x_write_reg_block(port, CP210X_SET_CHARS, &chars,
1172 				sizeof(chars));
1173 		if (ret) {
1174 			dev_err(&port->dev, "failed to set special chars: %d\n",
1175 					ret);
1176 		}
1177 	}
1178 
1179 	mutex_lock(&port_priv->mutex);
1180 
1181 	if (tty->termios.c_ospeed == 0) {
1182 		port_priv->dtr = false;
1183 		port_priv->rts = false;
1184 	} else if (old_termios && old_termios->c_ospeed == 0) {
1185 		port_priv->dtr = true;
1186 		port_priv->rts = true;
1187 	}
1188 
1189 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1190 			sizeof(flow_ctl));
1191 	if (ret)
1192 		goto out_unlock;
1193 
1194 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1195 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1196 
1197 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1198 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1199 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1200 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1201 	if (port_priv->dtr)
1202 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1203 	else
1204 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1205 
1206 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1207 	if (C_CRTSCTS(tty)) {
1208 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1209 		if (port_priv->rts)
1210 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1211 		else
1212 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1213 		crtscts = true;
1214 	} else {
1215 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1216 		if (port_priv->rts)
1217 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1218 		else
1219 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1220 		crtscts = false;
1221 	}
1222 
1223 	if (I_IXOFF(tty)) {
1224 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1225 
1226 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1227 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1228 	} else {
1229 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1230 	}
1231 
1232 	if (I_IXON(tty))
1233 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1234 	else
1235 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1236 
1237 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1238 			ctl_hs, flow_repl);
1239 
1240 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1241 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1242 
1243 	ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1244 			sizeof(flow_ctl));
1245 	if (ret)
1246 		goto out_unlock;
1247 
1248 	port_priv->crtscts = crtscts;
1249 out_unlock:
1250 	mutex_unlock(&port_priv->mutex);
1251 }
1252 
1253 static void cp210x_set_termios(struct tty_struct *tty,
1254 		               struct usb_serial_port *port,
1255 		               const struct ktermios *old_termios)
1256 {
1257 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1258 	u16 bits;
1259 	int ret;
1260 
1261 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios) &&
1262 			tty->termios.c_ospeed != 0)
1263 		return;
1264 
1265 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1266 		cp210x_change_speed(tty, port, old_termios);
1267 
1268 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1269 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1270 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1271 		tty->termios.c_cflag |= CS8;
1272 	}
1273 
1274 	bits = 0;
1275 
1276 	switch (C_CSIZE(tty)) {
1277 	case CS5:
1278 		bits |= BITS_DATA_5;
1279 		break;
1280 	case CS6:
1281 		bits |= BITS_DATA_6;
1282 		break;
1283 	case CS7:
1284 		bits |= BITS_DATA_7;
1285 		break;
1286 	case CS8:
1287 	default:
1288 		bits |= BITS_DATA_8;
1289 		break;
1290 	}
1291 
1292 	if (C_PARENB(tty)) {
1293 		if (C_CMSPAR(tty)) {
1294 			if (C_PARODD(tty))
1295 				bits |= BITS_PARITY_MARK;
1296 			else
1297 				bits |= BITS_PARITY_SPACE;
1298 		} else {
1299 			if (C_PARODD(tty))
1300 				bits |= BITS_PARITY_ODD;
1301 			else
1302 				bits |= BITS_PARITY_EVEN;
1303 		}
1304 	}
1305 
1306 	if (C_CSTOPB(tty))
1307 		bits |= BITS_STOP_2;
1308 	else
1309 		bits |= BITS_STOP_1;
1310 
1311 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1312 	if (ret)
1313 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1314 
1315 	cp210x_set_flow_control(tty, port, old_termios);
1316 
1317 	/*
1318 	 * Enable event-insertion mode only if input parity checking is
1319 	 * enabled for now.
1320 	 */
1321 	if (I_INPCK(tty))
1322 		cp210x_enable_event_mode(port);
1323 	else
1324 		cp210x_disable_event_mode(port);
1325 }
1326 
1327 static int cp210x_tiocmset(struct tty_struct *tty,
1328 		unsigned int set, unsigned int clear)
1329 {
1330 	struct usb_serial_port *port = tty->driver_data;
1331 	return cp210x_tiocmset_port(port, set, clear);
1332 }
1333 
1334 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1335 		unsigned int set, unsigned int clear)
1336 {
1337 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1338 	struct cp210x_flow_ctl flow_ctl;
1339 	u32 ctl_hs, flow_repl;
1340 	u16 control = 0;
1341 	int ret;
1342 
1343 	mutex_lock(&port_priv->mutex);
1344 
1345 	if (set & TIOCM_RTS) {
1346 		port_priv->rts = true;
1347 		control |= CONTROL_RTS;
1348 		control |= CONTROL_WRITE_RTS;
1349 	}
1350 	if (set & TIOCM_DTR) {
1351 		port_priv->dtr = true;
1352 		control |= CONTROL_DTR;
1353 		control |= CONTROL_WRITE_DTR;
1354 	}
1355 	if (clear & TIOCM_RTS) {
1356 		port_priv->rts = false;
1357 		control &= ~CONTROL_RTS;
1358 		control |= CONTROL_WRITE_RTS;
1359 	}
1360 	if (clear & TIOCM_DTR) {
1361 		port_priv->dtr = false;
1362 		control &= ~CONTROL_DTR;
1363 		control |= CONTROL_WRITE_DTR;
1364 	}
1365 
1366 	/*
1367 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1368 	 * flow control is enabled.
1369 	 */
1370 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1371 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1372 				sizeof(flow_ctl));
1373 		if (ret)
1374 			goto out_unlock;
1375 
1376 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1377 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1378 
1379 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1380 		if (port_priv->dtr)
1381 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1382 		else
1383 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1384 
1385 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1386 		if (port_priv->rts)
1387 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1388 		else
1389 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1390 
1391 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1392 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1393 
1394 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1395 				__func__, ctl_hs, flow_repl);
1396 
1397 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1398 				sizeof(flow_ctl));
1399 	} else {
1400 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1401 
1402 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1403 	}
1404 out_unlock:
1405 	mutex_unlock(&port_priv->mutex);
1406 
1407 	return ret;
1408 }
1409 
1410 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1411 {
1412 	if (on)
1413 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1414 	else
1415 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1416 }
1417 
1418 static int cp210x_tiocmget(struct tty_struct *tty)
1419 {
1420 	struct usb_serial_port *port = tty->driver_data;
1421 	u8 control;
1422 	int result;
1423 
1424 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1425 	if (result)
1426 		return result;
1427 
1428 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1429 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1430 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1431 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1432 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1433 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1434 
1435 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1436 
1437 	return result;
1438 }
1439 
1440 static int cp210x_break_ctl(struct tty_struct *tty, int break_state)
1441 {
1442 	struct usb_serial_port *port = tty->driver_data;
1443 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1444 	u16 state;
1445 
1446 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1447 		if (cp210x_interface_num(port->serial) == 1)
1448 			return -ENOTTY;
1449 	}
1450 
1451 	if (break_state == 0)
1452 		state = BREAK_OFF;
1453 	else
1454 		state = BREAK_ON;
1455 
1456 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1457 		state == BREAK_OFF ? "off" : "on");
1458 
1459 	return cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1460 }
1461 
1462 #ifdef CONFIG_GPIOLIB
1463 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1464 {
1465 	struct usb_serial *serial = gpiochip_get_data(gc);
1466 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1467 	u8 req_type;
1468 	u16 mask;
1469 	int result;
1470 	int len;
1471 
1472 	result = usb_autopm_get_interface(serial->interface);
1473 	if (result)
1474 		return result;
1475 
1476 	switch (priv->partnum) {
1477 	case CP210X_PARTNUM_CP2105:
1478 		req_type = REQTYPE_INTERFACE_TO_HOST;
1479 		len = 1;
1480 		break;
1481 	case CP210X_PARTNUM_CP2108:
1482 		req_type = REQTYPE_INTERFACE_TO_HOST;
1483 		len = 2;
1484 		break;
1485 	default:
1486 		req_type = REQTYPE_DEVICE_TO_HOST;
1487 		len = 1;
1488 		break;
1489 	}
1490 
1491 	mask = 0;
1492 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1493 					  &mask, len);
1494 
1495 	usb_autopm_put_interface(serial->interface);
1496 
1497 	if (result < 0)
1498 		return result;
1499 
1500 	le16_to_cpus(&mask);
1501 
1502 	return !!(mask & BIT(gpio));
1503 }
1504 
1505 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1506 {
1507 	struct usb_serial *serial = gpiochip_get_data(gc);
1508 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1509 	struct cp210x_gpio_write16 buf16;
1510 	struct cp210x_gpio_write buf;
1511 	u16 mask, state;
1512 	u16 wIndex;
1513 	int result;
1514 
1515 	if (value == 1)
1516 		state = BIT(gpio);
1517 	else
1518 		state = 0;
1519 
1520 	mask = BIT(gpio);
1521 
1522 	result = usb_autopm_get_interface(serial->interface);
1523 	if (result)
1524 		goto out;
1525 
1526 	switch (priv->partnum) {
1527 	case CP210X_PARTNUM_CP2105:
1528 		buf.mask = (u8)mask;
1529 		buf.state = (u8)state;
1530 		result = cp210x_write_vendor_block(serial,
1531 						   REQTYPE_HOST_TO_INTERFACE,
1532 						   CP210X_WRITE_LATCH, &buf,
1533 						   sizeof(buf));
1534 		break;
1535 	case CP210X_PARTNUM_CP2108:
1536 		buf16.mask = cpu_to_le16(mask);
1537 		buf16.state = cpu_to_le16(state);
1538 		result = cp210x_write_vendor_block(serial,
1539 						   REQTYPE_HOST_TO_INTERFACE,
1540 						   CP210X_WRITE_LATCH, &buf16,
1541 						   sizeof(buf16));
1542 		break;
1543 	default:
1544 		wIndex = state << 8 | mask;
1545 		result = usb_control_msg(serial->dev,
1546 					 usb_sndctrlpipe(serial->dev, 0),
1547 					 CP210X_VENDOR_SPECIFIC,
1548 					 REQTYPE_HOST_TO_DEVICE,
1549 					 CP210X_WRITE_LATCH,
1550 					 wIndex,
1551 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1552 		break;
1553 	}
1554 
1555 	usb_autopm_put_interface(serial->interface);
1556 out:
1557 	if (result < 0) {
1558 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1559 				result);
1560 	}
1561 }
1562 
1563 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1564 {
1565 	struct usb_serial *serial = gpiochip_get_data(gc);
1566 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1567 
1568 	return priv->gpio_input & BIT(gpio);
1569 }
1570 
1571 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1572 {
1573 	struct usb_serial *serial = gpiochip_get_data(gc);
1574 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1575 
1576 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1577 		/* hardware does not support an input mode */
1578 		return -ENOTSUPP;
1579 	}
1580 
1581 	/* push-pull pins cannot be changed to be inputs */
1582 	if (priv->gpio_pushpull & BIT(gpio))
1583 		return -EINVAL;
1584 
1585 	/* make sure to release pin if it is being driven low */
1586 	cp210x_gpio_set(gc, gpio, 1);
1587 
1588 	priv->gpio_input |= BIT(gpio);
1589 
1590 	return 0;
1591 }
1592 
1593 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1594 					int value)
1595 {
1596 	struct usb_serial *serial = gpiochip_get_data(gc);
1597 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1598 
1599 	priv->gpio_input &= ~BIT(gpio);
1600 	cp210x_gpio_set(gc, gpio, value);
1601 
1602 	return 0;
1603 }
1604 
1605 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1606 				  unsigned long config)
1607 {
1608 	struct usb_serial *serial = gpiochip_get_data(gc);
1609 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1610 	enum pin_config_param param = pinconf_to_config_param(config);
1611 
1612 	/* Succeed only if in correct mode (this can't be set at runtime) */
1613 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1614 	    (priv->gpio_pushpull & BIT(gpio)))
1615 		return 0;
1616 
1617 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1618 	    !(priv->gpio_pushpull & BIT(gpio)))
1619 		return 0;
1620 
1621 	return -ENOTSUPP;
1622 }
1623 
1624 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1625 		unsigned long *valid_mask, unsigned int ngpios)
1626 {
1627 	struct usb_serial *serial = gpiochip_get_data(gc);
1628 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1629 	struct device *dev = &serial->interface->dev;
1630 	unsigned long altfunc_mask = priv->gpio_altfunc;
1631 
1632 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1633 
1634 	if (bitmap_empty(valid_mask, ngpios))
1635 		dev_dbg(dev, "no pin configured for GPIO\n");
1636 	else
1637 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1638 				valid_mask);
1639 	return 0;
1640 }
1641 
1642 /*
1643  * This function is for configuring GPIO using shared pins, where other signals
1644  * are made unavailable by configuring the use of GPIO. This is believed to be
1645  * only applicable to the cp2105 at this point, the other devices supported by
1646  * this driver that provide GPIO do so in a way that does not impact other
1647  * signals and are thus expected to have very different initialisation.
1648  */
1649 static int cp2105_gpioconf_init(struct usb_serial *serial)
1650 {
1651 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1652 	struct cp210x_pin_mode mode;
1653 	struct cp210x_dual_port_config config;
1654 	u8 intf_num = cp210x_interface_num(serial);
1655 	u8 iface_config;
1656 	int result;
1657 
1658 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1659 					  CP210X_GET_DEVICEMODE, &mode,
1660 					  sizeof(mode));
1661 	if (result < 0)
1662 		return result;
1663 
1664 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1665 					  CP210X_GET_PORTCONFIG, &config,
1666 					  sizeof(config));
1667 	if (result < 0)
1668 		return result;
1669 
1670 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1671 	if (intf_num == 0) {
1672 		priv->gc.ngpio = 2;
1673 
1674 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1675 			/* mark all GPIOs of this interface as reserved */
1676 			priv->gpio_altfunc = 0xff;
1677 			return 0;
1678 		}
1679 
1680 		iface_config = config.eci_cfg;
1681 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1682 						CP210X_ECI_GPIO_MODE_MASK) >>
1683 						CP210X_ECI_GPIO_MODE_OFFSET);
1684 	} else if (intf_num == 1) {
1685 		priv->gc.ngpio = 3;
1686 
1687 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1688 			/* mark all GPIOs of this interface as reserved */
1689 			priv->gpio_altfunc = 0xff;
1690 			return 0;
1691 		}
1692 
1693 		iface_config = config.sci_cfg;
1694 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1695 						CP210X_SCI_GPIO_MODE_MASK) >>
1696 						CP210X_SCI_GPIO_MODE_OFFSET);
1697 	} else {
1698 		return -ENODEV;
1699 	}
1700 
1701 	/* mark all pins which are not in GPIO mode */
1702 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1703 		priv->gpio_altfunc |= BIT(0);
1704 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1705 			CP2105_GPIO1_RS485_MODE))
1706 		priv->gpio_altfunc |= BIT(1);
1707 
1708 	/* driver implementation for CP2105 only supports outputs */
1709 	priv->gpio_input = 0;
1710 
1711 	return 0;
1712 }
1713 
1714 static int cp2104_gpioconf_init(struct usb_serial *serial)
1715 {
1716 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1717 	struct cp210x_single_port_config config;
1718 	u8 iface_config;
1719 	u8 gpio_latch;
1720 	int result;
1721 	u8 i;
1722 
1723 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1724 					  CP210X_GET_PORTCONFIG, &config,
1725 					  sizeof(config));
1726 	if (result < 0)
1727 		return result;
1728 
1729 	priv->gc.ngpio = 4;
1730 
1731 	iface_config = config.device_cfg;
1732 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1733 					CP210X_GPIO_MODE_MASK) >>
1734 					CP210X_GPIO_MODE_OFFSET);
1735 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1736 					CP210X_GPIO_MODE_MASK) >>
1737 					CP210X_GPIO_MODE_OFFSET);
1738 
1739 	/* mark all pins which are not in GPIO mode */
1740 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1741 		priv->gpio_altfunc |= BIT(0);
1742 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1743 		priv->gpio_altfunc |= BIT(1);
1744 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1745 		priv->gpio_altfunc |= BIT(2);
1746 
1747 	/*
1748 	 * Like CP2102N, CP2104 has also no strict input and output pin
1749 	 * modes.
1750 	 * Do the same input mode emulation as CP2102N.
1751 	 */
1752 	for (i = 0; i < priv->gc.ngpio; ++i) {
1753 		/*
1754 		 * Set direction to "input" iff pin is open-drain and reset
1755 		 * value is 1.
1756 		 */
1757 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1758 			priv->gpio_input |= BIT(i);
1759 	}
1760 
1761 	return 0;
1762 }
1763 
1764 static int cp2108_gpio_init(struct usb_serial *serial)
1765 {
1766 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1767 	struct cp210x_quad_port_config config;
1768 	u16 gpio_latch;
1769 	int result;
1770 	u8 i;
1771 
1772 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1773 					  CP210X_GET_PORTCONFIG, &config,
1774 					  sizeof(config));
1775 	if (result < 0)
1776 		return result;
1777 
1778 	priv->gc.ngpio = 16;
1779 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1780 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1781 
1782 	/*
1783 	 * Mark all pins which are not in GPIO mode.
1784 	 *
1785 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1786 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1787 	 *
1788 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1789 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1790 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1791 	 */
1792 	for (i = 0; i < 4; i++) {
1793 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1794 			priv->gpio_altfunc |= BIT(i * 4);
1795 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1796 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1797 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1798 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1799 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1800 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1801 	}
1802 
1803 	/*
1804 	 * Like CP2102N, CP2108 has also no strict input and output pin
1805 	 * modes. Do the same input mode emulation as CP2102N.
1806 	 */
1807 	for (i = 0; i < priv->gc.ngpio; ++i) {
1808 		/*
1809 		 * Set direction to "input" iff pin is open-drain and reset
1810 		 * value is 1.
1811 		 */
1812 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1813 			priv->gpio_input |= BIT(i);
1814 	}
1815 
1816 	return 0;
1817 }
1818 
1819 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1820 {
1821 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1822 	const u16 config_size = 0x02a6;
1823 	u8 gpio_rst_latch;
1824 	u8 config_version;
1825 	u8 gpio_pushpull;
1826 	u8 *config_buf;
1827 	u8 gpio_latch;
1828 	u8 gpio_ctrl;
1829 	int result;
1830 	u8 i;
1831 
1832 	/*
1833 	 * Retrieve device configuration from the device.
1834 	 * The array received contains all customization settings done at the
1835 	 * factory/manufacturer. Format of the array is documented at the
1836 	 * time of writing at:
1837 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1838 	 */
1839 	config_buf = kmalloc(config_size, GFP_KERNEL);
1840 	if (!config_buf)
1841 		return -ENOMEM;
1842 
1843 	result = cp210x_read_vendor_block(serial,
1844 					  REQTYPE_DEVICE_TO_HOST,
1845 					  CP210X_READ_2NCONFIG,
1846 					  config_buf,
1847 					  config_size);
1848 	if (result < 0) {
1849 		kfree(config_buf);
1850 		return result;
1851 	}
1852 
1853 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1854 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1855 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1856 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1857 
1858 	kfree(config_buf);
1859 
1860 	/* Make sure this is a config format we understand. */
1861 	if (config_version != 0x01)
1862 		return -ENOTSUPP;
1863 
1864 	priv->gc.ngpio = 4;
1865 
1866 	/*
1867 	 * Get default pin states after reset. Needed so we can determine
1868 	 * the direction of an open-drain pin.
1869 	 */
1870 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1871 
1872 	/* 0 indicates open-drain mode, 1 is push-pull */
1873 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1874 
1875 	/* 0 indicates GPIO mode, 1 is alternate function */
1876 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1877 		/* QFN20 is special... */
1878 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1879 			priv->gpio_altfunc |= BIT(0);
1880 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1881 			priv->gpio_altfunc |= BIT(1);
1882 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1883 			priv->gpio_altfunc |= BIT(2);
1884 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1885 			priv->gpio_altfunc |= BIT(3);
1886 	} else {
1887 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1888 	}
1889 
1890 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1891 		/*
1892 		 * For the QFN28 package, GPIO4-6 are controlled by
1893 		 * the low three bits of the mode/latch fields.
1894 		 * Contrary to the document linked above, the bits for
1895 		 * the SUSPEND pins are elsewhere.  No alternate
1896 		 * function is available for these pins.
1897 		 */
1898 		priv->gc.ngpio = 7;
1899 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1900 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1901 	}
1902 
1903 	/*
1904 	 * The CP2102N does not strictly has input and output pin modes,
1905 	 * it only knows open-drain and push-pull modes which is set at
1906 	 * factory. An open-drain pin can function both as an
1907 	 * input or an output. We emulate input mode for open-drain pins
1908 	 * by making sure they are not driven low, and we do not allow
1909 	 * push-pull pins to be set as an input.
1910 	 */
1911 	for (i = 0; i < priv->gc.ngpio; ++i) {
1912 		/*
1913 		 * Set direction to "input" iff pin is open-drain and reset
1914 		 * value is 1.
1915 		 */
1916 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1917 			priv->gpio_input |= BIT(i);
1918 	}
1919 
1920 	return 0;
1921 }
1922 
1923 static int cp210x_gpio_init(struct usb_serial *serial)
1924 {
1925 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1926 	int result;
1927 
1928 	switch (priv->partnum) {
1929 	case CP210X_PARTNUM_CP2104:
1930 		result = cp2104_gpioconf_init(serial);
1931 		break;
1932 	case CP210X_PARTNUM_CP2105:
1933 		result = cp2105_gpioconf_init(serial);
1934 		break;
1935 	case CP210X_PARTNUM_CP2108:
1936 		/*
1937 		 * The GPIOs are not tied to any specific port so only register
1938 		 * once for interface 0.
1939 		 */
1940 		if (cp210x_interface_num(serial) != 0)
1941 			return 0;
1942 		result = cp2108_gpio_init(serial);
1943 		break;
1944 	case CP210X_PARTNUM_CP2102N_QFN28:
1945 	case CP210X_PARTNUM_CP2102N_QFN24:
1946 	case CP210X_PARTNUM_CP2102N_QFN20:
1947 		result = cp2102n_gpioconf_init(serial);
1948 		break;
1949 	default:
1950 		return 0;
1951 	}
1952 
1953 	if (result < 0)
1954 		return result;
1955 
1956 	priv->gc.label = "cp210x";
1957 	priv->gc.get_direction = cp210x_gpio_direction_get;
1958 	priv->gc.direction_input = cp210x_gpio_direction_input;
1959 	priv->gc.direction_output = cp210x_gpio_direction_output;
1960 	priv->gc.get = cp210x_gpio_get;
1961 	priv->gc.set = cp210x_gpio_set;
1962 	priv->gc.set_config = cp210x_gpio_set_config;
1963 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1964 	priv->gc.owner = THIS_MODULE;
1965 	priv->gc.parent = &serial->interface->dev;
1966 	priv->gc.base = -1;
1967 	priv->gc.can_sleep = true;
1968 
1969 	result = gpiochip_add_data(&priv->gc, serial);
1970 	if (!result)
1971 		priv->gpio_registered = true;
1972 
1973 	return result;
1974 }
1975 
1976 static void cp210x_gpio_remove(struct usb_serial *serial)
1977 {
1978 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1979 
1980 	if (priv->gpio_registered) {
1981 		gpiochip_remove(&priv->gc);
1982 		priv->gpio_registered = false;
1983 	}
1984 }
1985 
1986 #else
1987 
1988 static int cp210x_gpio_init(struct usb_serial *serial)
1989 {
1990 	return 0;
1991 }
1992 
1993 static void cp210x_gpio_remove(struct usb_serial *serial)
1994 {
1995 	/* Nothing to do */
1996 }
1997 
1998 #endif
1999 
2000 static int cp210x_port_probe(struct usb_serial_port *port)
2001 {
2002 	struct usb_serial *serial = port->serial;
2003 	struct cp210x_port_private *port_priv;
2004 
2005 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
2006 	if (!port_priv)
2007 		return -ENOMEM;
2008 
2009 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
2010 	mutex_init(&port_priv->mutex);
2011 
2012 	usb_set_serial_port_data(port, port_priv);
2013 
2014 	return 0;
2015 }
2016 
2017 static void cp210x_port_remove(struct usb_serial_port *port)
2018 {
2019 	struct cp210x_port_private *port_priv;
2020 
2021 	port_priv = usb_get_serial_port_data(port);
2022 	kfree(port_priv);
2023 }
2024 
2025 static void cp210x_init_max_speed(struct usb_serial *serial)
2026 {
2027 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2028 	bool use_actual_rate = false;
2029 	speed_t min = 300;
2030 	speed_t max;
2031 
2032 	switch (priv->partnum) {
2033 	case CP210X_PARTNUM_CP2101:
2034 		max = 921600;
2035 		break;
2036 	case CP210X_PARTNUM_CP2102:
2037 	case CP210X_PARTNUM_CP2103:
2038 		max = 1000000;
2039 		break;
2040 	case CP210X_PARTNUM_CP2104:
2041 		use_actual_rate = true;
2042 		max = 2000000;
2043 		break;
2044 	case CP210X_PARTNUM_CP2108:
2045 		max = 2000000;
2046 		break;
2047 	case CP210X_PARTNUM_CP2105:
2048 		if (cp210x_interface_num(serial) == 0) {
2049 			use_actual_rate = true;
2050 			max = 2000000;	/* ECI */
2051 		} else {
2052 			min = 2400;
2053 			max = 921600;	/* SCI */
2054 		}
2055 		break;
2056 	case CP210X_PARTNUM_CP2102N_QFN28:
2057 	case CP210X_PARTNUM_CP2102N_QFN24:
2058 	case CP210X_PARTNUM_CP2102N_QFN20:
2059 		use_actual_rate = true;
2060 		max = 3000000;
2061 		break;
2062 	default:
2063 		max = 2000000;
2064 		break;
2065 	}
2066 
2067 	priv->min_speed = min;
2068 	priv->max_speed = max;
2069 	priv->use_actual_rate = use_actual_rate;
2070 }
2071 
2072 static void cp2102_determine_quirks(struct usb_serial *serial)
2073 {
2074 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2075 	u8 *buf;
2076 	int ret;
2077 
2078 	buf = kmalloc(2, GFP_KERNEL);
2079 	if (!buf)
2080 		return;
2081 	/*
2082 	 * Some (possibly counterfeit) CP2102 do not support event-insertion
2083 	 * mode and respond differently to malformed vendor requests.
2084 	 * Specifically, they return one instead of two bytes when sent a
2085 	 * two-byte part-number request.
2086 	 */
2087 	ret = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2088 			CP210X_VENDOR_SPECIFIC, REQTYPE_DEVICE_TO_HOST,
2089 			CP210X_GET_PARTNUM, 0, buf, 2, USB_CTRL_GET_TIMEOUT);
2090 	if (ret == 1) {
2091 		dev_dbg(&serial->interface->dev,
2092 				"device does not support event-insertion mode\n");
2093 		priv->no_event_mode = true;
2094 	}
2095 
2096 	kfree(buf);
2097 }
2098 
2099 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2100 {
2101 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2102 	u8 ver[3];
2103 	int ret;
2104 
2105 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2106 			ver, sizeof(ver));
2107 	if (ret)
2108 		return ret;
2109 
2110 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2111 			ver[0], ver[1], ver[2]);
2112 
2113 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2114 
2115 	return 0;
2116 }
2117 
2118 static void cp210x_determine_type(struct usb_serial *serial)
2119 {
2120 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2121 	int ret;
2122 
2123 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2124 			CP210X_GET_PARTNUM, &priv->partnum,
2125 			sizeof(priv->partnum));
2126 	if (ret < 0) {
2127 		dev_warn(&serial->interface->dev,
2128 				"querying part number failed\n");
2129 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2130 		return;
2131 	}
2132 
2133 	dev_dbg(&serial->interface->dev, "partnum = 0x%02x\n", priv->partnum);
2134 
2135 	switch (priv->partnum) {
2136 	case CP210X_PARTNUM_CP2102:
2137 		cp2102_determine_quirks(serial);
2138 		break;
2139 	case CP210X_PARTNUM_CP2105:
2140 	case CP210X_PARTNUM_CP2108:
2141 		cp210x_get_fw_version(serial, CP210X_GET_FW_VER);
2142 		break;
2143 	case CP210X_PARTNUM_CP2102N_QFN28:
2144 	case CP210X_PARTNUM_CP2102N_QFN24:
2145 	case CP210X_PARTNUM_CP2102N_QFN20:
2146 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2147 		if (ret)
2148 			break;
2149 		if (priv->fw_version <= 0x10004)
2150 			priv->no_flow_control = true;
2151 		break;
2152 	default:
2153 		break;
2154 	}
2155 }
2156 
2157 static int cp210x_attach(struct usb_serial *serial)
2158 {
2159 	int result;
2160 	struct cp210x_serial_private *priv;
2161 
2162 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2163 	if (!priv)
2164 		return -ENOMEM;
2165 
2166 	usb_set_serial_data(serial, priv);
2167 
2168 	cp210x_determine_type(serial);
2169 	cp210x_init_max_speed(serial);
2170 
2171 	result = cp210x_gpio_init(serial);
2172 	if (result < 0) {
2173 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2174 				result);
2175 	}
2176 
2177 	return 0;
2178 }
2179 
2180 static void cp210x_disconnect(struct usb_serial *serial)
2181 {
2182 	cp210x_gpio_remove(serial);
2183 }
2184 
2185 static void cp210x_release(struct usb_serial *serial)
2186 {
2187 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2188 
2189 	cp210x_gpio_remove(serial);
2190 
2191 	kfree(priv);
2192 }
2193 
2194 module_usb_serial_driver(serial_drivers, id_table);
2195 
2196 MODULE_DESCRIPTION(DRIVER_DESC);
2197 MODULE_LICENSE("GPL v2");
2198