xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 7587cdef)
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 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, 0x8414) }, /* Decagon USB Cable Adapter */
134 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
135 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
136 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
137 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
138 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
139 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
140 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
141 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
142 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
143 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
144 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
145 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
146 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
147 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
148 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
149 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
150 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
151 	{ USB_DEVICE(0x10C4, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
152 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
153 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
154 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
155 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
156 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
157 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
158 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
159 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
160 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
161 	{ USB_DEVICE(0x10C4, 0x8A5B) }, /* CEL EM3588 ZigBee USB Stick */
162 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
163 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
164 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
165 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
166 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
167 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
168 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
169 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
170 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
171 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
172 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
173 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
174 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
175 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
176 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
177 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
178 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
179 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
180 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
181 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
182 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
183 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
184 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
185 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
186 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
187 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
188 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
189 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
190 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
191 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
192 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
193 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
194 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
195 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
196 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
197 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
198 	{ USB_DEVICE(0x17A8, 0x0101) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Int Ant) */
199 	{ USB_DEVICE(0x17A8, 0x0102) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Ext Ant) */
200 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
201 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
202 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
203 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
204 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
205 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
206 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
207 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
208 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
209 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
210 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
211 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 M.2 Key E serial interface */
212 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 Display serial interface */
213 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
214 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
215 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
216 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
217 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
218 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
219 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
220 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
221 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
222 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
223 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
224 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
225 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
226 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
227 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
228 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
229 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
230 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
231 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
232 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
233 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
234 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
235 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
236 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
237 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
238 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
239 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
240 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
241 	{ USB_DEVICE(0x2184, 0x0030) }, /* GW Instek GDM-834x Digital Multimeter */
242 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
243 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
244 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
245 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
246 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
247 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
248 	{ } /* Terminating Entry */
249 };
250 
251 MODULE_DEVICE_TABLE(usb, id_table);
252 
253 struct cp210x_serial_private {
254 #ifdef CONFIG_GPIOLIB
255 	struct gpio_chip	gc;
256 	bool			gpio_registered;
257 	u16			gpio_pushpull;
258 	u16			gpio_altfunc;
259 	u16			gpio_input;
260 #endif
261 	u8			partnum;
262 	u32			fw_version;
263 	speed_t			min_speed;
264 	speed_t			max_speed;
265 	bool			use_actual_rate;
266 	bool			no_flow_control;
267 	bool			no_event_mode;
268 };
269 
270 enum cp210x_event_state {
271 	ES_DATA,
272 	ES_ESCAPE,
273 	ES_LSR,
274 	ES_LSR_DATA_0,
275 	ES_LSR_DATA_1,
276 	ES_MSR
277 };
278 
279 struct cp210x_port_private {
280 	u8			bInterfaceNumber;
281 	bool			event_mode;
282 	enum cp210x_event_state event_state;
283 	u8			lsr;
284 
285 	struct mutex		mutex;
286 	bool			crtscts;
287 	bool			dtr;
288 	bool			rts;
289 };
290 
291 static struct usb_serial_driver cp210x_device = {
292 	.driver = {
293 		.owner =	THIS_MODULE,
294 		.name =		"cp210x",
295 	},
296 	.id_table		= id_table,
297 	.num_ports		= 1,
298 	.bulk_in_size		= 256,
299 	.bulk_out_size		= 256,
300 	.open			= cp210x_open,
301 	.close			= cp210x_close,
302 	.break_ctl		= cp210x_break_ctl,
303 	.set_termios		= cp210x_set_termios,
304 	.tx_empty		= cp210x_tx_empty,
305 	.throttle		= usb_serial_generic_throttle,
306 	.unthrottle		= usb_serial_generic_unthrottle,
307 	.tiocmget		= cp210x_tiocmget,
308 	.tiocmset		= cp210x_tiocmset,
309 	.get_icount		= usb_serial_generic_get_icount,
310 	.attach			= cp210x_attach,
311 	.disconnect		= cp210x_disconnect,
312 	.release		= cp210x_release,
313 	.port_probe		= cp210x_port_probe,
314 	.port_remove		= cp210x_port_remove,
315 	.dtr_rts		= cp210x_dtr_rts,
316 	.process_read_urb	= cp210x_process_read_urb,
317 };
318 
319 static struct usb_serial_driver * const serial_drivers[] = {
320 	&cp210x_device, NULL
321 };
322 
323 /* Config request types */
324 #define REQTYPE_HOST_TO_INTERFACE	0x41
325 #define REQTYPE_INTERFACE_TO_HOST	0xc1
326 #define REQTYPE_HOST_TO_DEVICE	0x40
327 #define REQTYPE_DEVICE_TO_HOST	0xc0
328 
329 /* Config request codes */
330 #define CP210X_IFC_ENABLE	0x00
331 #define CP210X_SET_BAUDDIV	0x01
332 #define CP210X_GET_BAUDDIV	0x02
333 #define CP210X_SET_LINE_CTL	0x03
334 #define CP210X_GET_LINE_CTL	0x04
335 #define CP210X_SET_BREAK	0x05
336 #define CP210X_IMM_CHAR		0x06
337 #define CP210X_SET_MHS		0x07
338 #define CP210X_GET_MDMSTS	0x08
339 #define CP210X_SET_XON		0x09
340 #define CP210X_SET_XOFF		0x0A
341 #define CP210X_SET_EVENTMASK	0x0B
342 #define CP210X_GET_EVENTMASK	0x0C
343 #define CP210X_SET_CHAR		0x0D
344 #define CP210X_GET_CHARS	0x0E
345 #define CP210X_GET_PROPS	0x0F
346 #define CP210X_GET_COMM_STATUS	0x10
347 #define CP210X_RESET		0x11
348 #define CP210X_PURGE		0x12
349 #define CP210X_SET_FLOW		0x13
350 #define CP210X_GET_FLOW		0x14
351 #define CP210X_EMBED_EVENTS	0x15
352 #define CP210X_GET_EVENTSTATE	0x16
353 #define CP210X_SET_CHARS	0x19
354 #define CP210X_GET_BAUDRATE	0x1D
355 #define CP210X_SET_BAUDRATE	0x1E
356 #define CP210X_VENDOR_SPECIFIC	0xFF
357 
358 /* CP210X_IFC_ENABLE */
359 #define UART_ENABLE		0x0001
360 #define UART_DISABLE		0x0000
361 
362 /* CP210X_(SET|GET)_BAUDDIV */
363 #define BAUD_RATE_GEN_FREQ	0x384000
364 
365 /* CP210X_(SET|GET)_LINE_CTL */
366 #define BITS_DATA_MASK		0X0f00
367 #define BITS_DATA_5		0X0500
368 #define BITS_DATA_6		0X0600
369 #define BITS_DATA_7		0X0700
370 #define BITS_DATA_8		0X0800
371 #define BITS_DATA_9		0X0900
372 
373 #define BITS_PARITY_MASK	0x00f0
374 #define BITS_PARITY_NONE	0x0000
375 #define BITS_PARITY_ODD		0x0010
376 #define BITS_PARITY_EVEN	0x0020
377 #define BITS_PARITY_MARK	0x0030
378 #define BITS_PARITY_SPACE	0x0040
379 
380 #define BITS_STOP_MASK		0x000f
381 #define BITS_STOP_1		0x0000
382 #define BITS_STOP_1_5		0x0001
383 #define BITS_STOP_2		0x0002
384 
385 /* CP210X_SET_BREAK */
386 #define BREAK_ON		0x0001
387 #define BREAK_OFF		0x0000
388 
389 /* CP210X_(SET_MHS|GET_MDMSTS) */
390 #define CONTROL_DTR		0x0001
391 #define CONTROL_RTS		0x0002
392 #define CONTROL_CTS		0x0010
393 #define CONTROL_DSR		0x0020
394 #define CONTROL_RING		0x0040
395 #define CONTROL_DCD		0x0080
396 #define CONTROL_WRITE_DTR	0x0100
397 #define CONTROL_WRITE_RTS	0x0200
398 
399 /* CP210X_(GET|SET)_CHARS */
400 struct cp210x_special_chars {
401 	u8	bEofChar;
402 	u8	bErrorChar;
403 	u8	bBreakChar;
404 	u8	bEventChar;
405 	u8	bXonChar;
406 	u8	bXoffChar;
407 };
408 
409 /* CP210X_VENDOR_SPECIFIC values */
410 #define CP210X_GET_FW_VER	0x000E
411 #define CP210X_READ_2NCONFIG	0x000E
412 #define CP210X_GET_FW_VER_2N	0x0010
413 #define CP210X_READ_LATCH	0x00C2
414 #define CP210X_GET_PARTNUM	0x370B
415 #define CP210X_GET_PORTCONFIG	0x370C
416 #define CP210X_GET_DEVICEMODE	0x3711
417 #define CP210X_WRITE_LATCH	0x37E1
418 
419 /* Part number definitions */
420 #define CP210X_PARTNUM_CP2101	0x01
421 #define CP210X_PARTNUM_CP2102	0x02
422 #define CP210X_PARTNUM_CP2103	0x03
423 #define CP210X_PARTNUM_CP2104	0x04
424 #define CP210X_PARTNUM_CP2105	0x05
425 #define CP210X_PARTNUM_CP2108	0x08
426 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
427 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
428 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
429 #define CP210X_PARTNUM_UNKNOWN	0xFF
430 
431 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
432 struct cp210x_comm_status {
433 	__le32   ulErrors;
434 	__le32   ulHoldReasons;
435 	__le32   ulAmountInInQueue;
436 	__le32   ulAmountInOutQueue;
437 	u8       bEofReceived;
438 	u8       bWaitForImmediate;
439 	u8       bReserved;
440 } __packed;
441 
442 /*
443  * CP210X_PURGE - 16 bits passed in wValue of USB request.
444  * SiLabs app note AN571 gives a strange description of the 4 bits:
445  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
446  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
447  */
448 #define PURGE_ALL		0x000f
449 
450 /* CP210X_EMBED_EVENTS */
451 #define CP210X_ESCCHAR		0xec
452 
453 #define CP210X_LSR_OVERRUN	BIT(1)
454 #define CP210X_LSR_PARITY	BIT(2)
455 #define CP210X_LSR_FRAME	BIT(3)
456 #define CP210X_LSR_BREAK	BIT(4)
457 
458 
459 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
460 struct cp210x_flow_ctl {
461 	__le32	ulControlHandshake;
462 	__le32	ulFlowReplace;
463 	__le32	ulXonLimit;
464 	__le32	ulXoffLimit;
465 };
466 
467 /* cp210x_flow_ctl::ulControlHandshake */
468 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
469 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
470 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
471 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
472 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
473 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
474 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
475 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
476 
477 /* cp210x_flow_ctl::ulFlowReplace */
478 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
479 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
480 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
481 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
482 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
483 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
484 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
485 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
486 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
487 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
488 
489 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
490 struct cp210x_pin_mode {
491 	u8	eci;
492 	u8	sci;
493 };
494 
495 #define CP210X_PIN_MODE_MODEM		0
496 #define CP210X_PIN_MODE_GPIO		BIT(0)
497 
498 /*
499  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
500  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
501  */
502 struct cp210x_dual_port_config {
503 	__le16	gpio_mode;
504 	u8	__pad0[2];
505 	__le16	reset_state;
506 	u8	__pad1[4];
507 	__le16	suspend_state;
508 	u8	sci_cfg;
509 	u8	eci_cfg;
510 	u8	device_cfg;
511 } __packed;
512 
513 /*
514  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
515  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
516  */
517 struct cp210x_single_port_config {
518 	__le16	gpio_mode;
519 	u8	__pad0[2];
520 	__le16	reset_state;
521 	u8	__pad1[4];
522 	__le16	suspend_state;
523 	u8	device_cfg;
524 } __packed;
525 
526 /* GPIO modes */
527 #define CP210X_SCI_GPIO_MODE_OFFSET	9
528 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
529 
530 #define CP210X_ECI_GPIO_MODE_OFFSET	2
531 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
532 
533 #define CP210X_GPIO_MODE_OFFSET		8
534 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
535 
536 /* CP2105 port configuration values */
537 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
538 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
539 #define CP2105_GPIO1_RS485_MODE		BIT(2)
540 
541 /* CP2104 port configuration values */
542 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
543 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
544 #define CP2104_GPIO2_RS485_MODE		BIT(2)
545 
546 struct cp210x_quad_port_state {
547 	__le16 gpio_mode_pb0;
548 	__le16 gpio_mode_pb1;
549 	__le16 gpio_mode_pb2;
550 	__le16 gpio_mode_pb3;
551 	__le16 gpio_mode_pb4;
552 
553 	__le16 gpio_lowpower_pb0;
554 	__le16 gpio_lowpower_pb1;
555 	__le16 gpio_lowpower_pb2;
556 	__le16 gpio_lowpower_pb3;
557 	__le16 gpio_lowpower_pb4;
558 
559 	__le16 gpio_latch_pb0;
560 	__le16 gpio_latch_pb1;
561 	__le16 gpio_latch_pb2;
562 	__le16 gpio_latch_pb3;
563 	__le16 gpio_latch_pb4;
564 };
565 
566 /*
567  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
568  * on a CP2108 chip.
569  *
570  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
571  */
572 struct cp210x_quad_port_config {
573 	struct cp210x_quad_port_state reset_state;
574 	struct cp210x_quad_port_state suspend_state;
575 	u8 ipdelay_ifc[4];
576 	u8 enhancedfxn_ifc[4];
577 	u8 enhancedfxn_device;
578 	u8 extclkfreq[4];
579 } __packed;
580 
581 #define CP2108_EF_IFC_GPIO_TXLED		0x01
582 #define CP2108_EF_IFC_GPIO_RXLED		0x02
583 #define CP2108_EF_IFC_GPIO_RS485		0x04
584 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
585 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
586 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
587 
588 /* CP2102N configuration array indices */
589 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
590 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
591 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
592 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
593 
594 /* CP2102N QFN20 port configuration values */
595 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
596 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
597 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
598 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
599 
600 /*
601  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
602  * for CP2102N, CP2103, CP2104 and CP2105.
603  */
604 struct cp210x_gpio_write {
605 	u8	mask;
606 	u8	state;
607 };
608 
609 /*
610  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
611  * for CP2108.
612  */
613 struct cp210x_gpio_write16 {
614 	__le16	mask;
615 	__le16	state;
616 };
617 
618 /*
619  * Helper to get interface number when we only have struct usb_serial.
620  */
621 static u8 cp210x_interface_num(struct usb_serial *serial)
622 {
623 	struct usb_host_interface *cur_altsetting;
624 
625 	cur_altsetting = serial->interface->cur_altsetting;
626 
627 	return cur_altsetting->desc.bInterfaceNumber;
628 }
629 
630 /*
631  * Reads a variable-sized block of CP210X_ registers, identified by req.
632  * Returns data into buf in native USB byte order.
633  */
634 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
635 		void *buf, int bufsize)
636 {
637 	struct usb_serial *serial = port->serial;
638 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
639 	int result;
640 
641 
642 	result = usb_control_msg_recv(serial->dev, 0, req,
643 			REQTYPE_INTERFACE_TO_HOST, 0,
644 			port_priv->bInterfaceNumber, buf, bufsize,
645 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
646 	if (result) {
647 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
648 				req, bufsize, result);
649 		return result;
650 	}
651 
652 	return 0;
653 }
654 
655 /*
656  * Reads any 8-bit CP210X_ register identified by req.
657  */
658 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
659 {
660 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
661 }
662 
663 /*
664  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
665  * Returns data into buf in native USB byte order.
666  */
667 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
668 				    void *buf, int bufsize)
669 {
670 	int result;
671 
672 	result = usb_control_msg_recv(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
673 			type, val, cp210x_interface_num(serial), buf, bufsize,
674 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
675 	if (result) {
676 		dev_err(&serial->interface->dev,
677 			"failed to get vendor val 0x%04x size %d: %d\n", val,
678 			bufsize, result);
679 		return result;
680 	}
681 
682 	return 0;
683 }
684 
685 /*
686  * Writes any 16-bit CP210X_ register (req) whose value is passed
687  * entirely in the wValue field of the USB request.
688  */
689 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
690 {
691 	struct usb_serial *serial = port->serial;
692 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
693 	int result;
694 
695 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
696 			req, REQTYPE_HOST_TO_INTERFACE, val,
697 			port_priv->bInterfaceNumber, NULL, 0,
698 			USB_CTRL_SET_TIMEOUT);
699 	if (result < 0) {
700 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
701 				req, result);
702 	}
703 
704 	return result;
705 }
706 
707 /*
708  * Writes a variable-sized block of CP210X_ registers, identified by req.
709  * Data in buf must be in native USB byte order.
710  */
711 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
712 		void *buf, int bufsize)
713 {
714 	struct usb_serial *serial = port->serial;
715 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
716 	int result;
717 
718 	result = usb_control_msg_send(serial->dev, 0, req,
719 			REQTYPE_HOST_TO_INTERFACE, 0,
720 			port_priv->bInterfaceNumber, buf, bufsize,
721 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
722 	if (result) {
723 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
724 				req, bufsize, result);
725 		return result;
726 	}
727 
728 	return 0;
729 }
730 
731 /*
732  * Writes any 32-bit CP210X_ register identified by req.
733  */
734 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
735 {
736 	__le32 le32_val;
737 
738 	le32_val = cpu_to_le32(val);
739 
740 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
741 }
742 
743 #ifdef CONFIG_GPIOLIB
744 /*
745  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
746  * Data in buf must be in native USB byte order.
747  */
748 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
749 				     u16 val, void *buf, int bufsize)
750 {
751 	int result;
752 
753 	result = usb_control_msg_send(serial->dev, 0, CP210X_VENDOR_SPECIFIC,
754 			type, val, cp210x_interface_num(serial), buf, bufsize,
755 			USB_CTRL_SET_TIMEOUT, GFP_KERNEL);
756 	if (result) {
757 		dev_err(&serial->interface->dev,
758 			"failed to set vendor val 0x%04x size %d: %d\n", val,
759 			bufsize, result);
760 		return result;
761 	}
762 
763 	return 0;
764 }
765 #endif
766 
767 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
768 {
769 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
770 	int result;
771 
772 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
773 	if (result) {
774 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
775 		return result;
776 	}
777 
778 	if (tty)
779 		cp210x_set_termios(tty, port, NULL);
780 
781 	result = usb_serial_generic_open(tty, port);
782 	if (result)
783 		goto err_disable;
784 
785 	return 0;
786 
787 err_disable:
788 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
789 	port_priv->event_mode = false;
790 
791 	return result;
792 }
793 
794 static void cp210x_close(struct usb_serial_port *port)
795 {
796 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
797 
798 	usb_serial_generic_close(port);
799 
800 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
801 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
802 
803 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
804 
805 	/* Disabling the interface disables event-insertion mode. */
806 	port_priv->event_mode = false;
807 }
808 
809 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
810 {
811 	if (lsr & CP210X_LSR_BREAK) {
812 		port->icount.brk++;
813 		*flag = TTY_BREAK;
814 	} else if (lsr & CP210X_LSR_PARITY) {
815 		port->icount.parity++;
816 		*flag = TTY_PARITY;
817 	} else if (lsr & CP210X_LSR_FRAME) {
818 		port->icount.frame++;
819 		*flag = TTY_FRAME;
820 	}
821 
822 	if (lsr & CP210X_LSR_OVERRUN) {
823 		port->icount.overrun++;
824 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
825 	}
826 }
827 
828 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
829 {
830 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
831 
832 	switch (port_priv->event_state) {
833 	case ES_DATA:
834 		if (*ch == CP210X_ESCCHAR) {
835 			port_priv->event_state = ES_ESCAPE;
836 			break;
837 		}
838 		return false;
839 	case ES_ESCAPE:
840 		switch (*ch) {
841 		case 0:
842 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
843 			*ch = CP210X_ESCCHAR;
844 			port_priv->event_state = ES_DATA;
845 			return false;
846 		case 1:
847 			port_priv->event_state = ES_LSR_DATA_0;
848 			break;
849 		case 2:
850 			port_priv->event_state = ES_LSR;
851 			break;
852 		case 3:
853 			port_priv->event_state = ES_MSR;
854 			break;
855 		default:
856 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
857 			port_priv->event_state = ES_DATA;
858 			break;
859 		}
860 		break;
861 	case ES_LSR_DATA_0:
862 		port_priv->lsr = *ch;
863 		port_priv->event_state = ES_LSR_DATA_1;
864 		break;
865 	case ES_LSR_DATA_1:
866 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
867 				__func__, port_priv->lsr, *ch);
868 		cp210x_process_lsr(port, port_priv->lsr, flag);
869 		port_priv->event_state = ES_DATA;
870 		return false;
871 	case ES_LSR:
872 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
873 		port_priv->lsr = *ch;
874 		cp210x_process_lsr(port, port_priv->lsr, flag);
875 		port_priv->event_state = ES_DATA;
876 		break;
877 	case ES_MSR:
878 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
879 		/* unimplemented */
880 		port_priv->event_state = ES_DATA;
881 		break;
882 	}
883 
884 	return true;
885 }
886 
887 static void cp210x_process_read_urb(struct urb *urb)
888 {
889 	struct usb_serial_port *port = urb->context;
890 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
891 	unsigned char *ch = urb->transfer_buffer;
892 	char flag;
893 	int i;
894 
895 	if (!urb->actual_length)
896 		return;
897 
898 	if (port_priv->event_mode) {
899 		for (i = 0; i < urb->actual_length; i++, ch++) {
900 			flag = TTY_NORMAL;
901 
902 			if (cp210x_process_char(port, ch, &flag))
903 				continue;
904 
905 			tty_insert_flip_char(&port->port, *ch, flag);
906 		}
907 	} else {
908 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
909 	}
910 	tty_flip_buffer_push(&port->port);
911 }
912 
913 /*
914  * Read how many bytes are waiting in the TX queue.
915  */
916 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
917 		u32 *count)
918 {
919 	struct usb_serial *serial = port->serial;
920 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
921 	struct cp210x_comm_status sts;
922 	int result;
923 
924 	result = usb_control_msg_recv(serial->dev, 0, CP210X_GET_COMM_STATUS,
925 			REQTYPE_INTERFACE_TO_HOST, 0,
926 			port_priv->bInterfaceNumber, &sts, sizeof(sts),
927 			USB_CTRL_GET_TIMEOUT, GFP_KERNEL);
928 	if (result) {
929 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
930 		return result;
931 	}
932 
933 	*count = le32_to_cpu(sts.ulAmountInOutQueue);
934 
935 	return 0;
936 }
937 
938 static bool cp210x_tx_empty(struct usb_serial_port *port)
939 {
940 	int err;
941 	u32 count;
942 
943 	err = cp210x_get_tx_queue_byte_count(port, &count);
944 	if (err)
945 		return true;
946 
947 	return !count;
948 }
949 
950 struct cp210x_rate {
951 	speed_t rate;
952 	speed_t high;
953 };
954 
955 static const struct cp210x_rate cp210x_an205_table1[] = {
956 	{ 300, 300 },
957 	{ 600, 600 },
958 	{ 1200, 1200 },
959 	{ 1800, 1800 },
960 	{ 2400, 2400 },
961 	{ 4000, 4000 },
962 	{ 4800, 4803 },
963 	{ 7200, 7207 },
964 	{ 9600, 9612 },
965 	{ 14400, 14428 },
966 	{ 16000, 16062 },
967 	{ 19200, 19250 },
968 	{ 28800, 28912 },
969 	{ 38400, 38601 },
970 	{ 51200, 51558 },
971 	{ 56000, 56280 },
972 	{ 57600, 58053 },
973 	{ 64000, 64111 },
974 	{ 76800, 77608 },
975 	{ 115200, 117028 },
976 	{ 128000, 129347 },
977 	{ 153600, 156868 },
978 	{ 230400, 237832 },
979 	{ 250000, 254234 },
980 	{ 256000, 273066 },
981 	{ 460800, 491520 },
982 	{ 500000, 567138 },
983 	{ 576000, 670254 },
984 	{ 921600, UINT_MAX }
985 };
986 
987 /*
988  * Quantises the baud rate as per AN205 Table 1
989  */
990 static speed_t cp210x_get_an205_rate(speed_t baud)
991 {
992 	int i;
993 
994 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
995 		if (baud <= cp210x_an205_table1[i].high)
996 			break;
997 	}
998 
999 	return cp210x_an205_table1[i].rate;
1000 }
1001 
1002 static speed_t cp210x_get_actual_rate(speed_t baud)
1003 {
1004 	unsigned int prescale = 1;
1005 	unsigned int div;
1006 
1007 	if (baud <= 365)
1008 		prescale = 4;
1009 
1010 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1011 	baud = 48000000 / (2 * prescale * div);
1012 
1013 	return baud;
1014 }
1015 
1016 /*
1017  * CP2101 supports the following baud rates:
1018  *
1019  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1020  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1021  *
1022  * CP2102 and CP2103 support the following additional rates:
1023  *
1024  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1025  *	576000
1026  *
1027  * The device will map a requested rate to a supported one, but the result
1028  * of requests for rates greater than 1053257 is undefined (see AN205).
1029  *
1030  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1031  * respectively, with an error less than 1%. The actual rates are determined
1032  * by
1033  *
1034  *	div = round(freq / (2 x prescale x request))
1035  *	actual = freq / (2 x prescale x div)
1036  *
1037  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1038  * or 1 otherwise.
1039  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1040  * otherwise.
1041  */
1042 static void cp210x_change_speed(struct tty_struct *tty,
1043 				struct usb_serial_port *port,
1044 				const struct ktermios *old_termios)
1045 {
1046 	struct usb_serial *serial = port->serial;
1047 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1048 	u32 baud;
1049 
1050 	/*
1051 	 * This maps the requested rate to the actual rate, a valid rate on
1052 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1053 	 *
1054 	 * NOTE: B0 is not implemented.
1055 	 */
1056 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1057 
1058 	if (priv->use_actual_rate)
1059 		baud = cp210x_get_actual_rate(baud);
1060 	else if (baud < 1000000)
1061 		baud = cp210x_get_an205_rate(baud);
1062 
1063 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1064 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1065 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1066 		if (old_termios)
1067 			baud = old_termios->c_ospeed;
1068 		else
1069 			baud = 9600;
1070 	}
1071 
1072 	tty_encode_baud_rate(tty, baud, baud);
1073 }
1074 
1075 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1076 {
1077 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1078 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1079 	int ret;
1080 
1081 	if (port_priv->event_mode)
1082 		return;
1083 
1084 	if (priv->no_event_mode)
1085 		return;
1086 
1087 	port_priv->event_state = ES_DATA;
1088 	port_priv->event_mode = true;
1089 
1090 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1091 	if (ret) {
1092 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1093 		port_priv->event_mode = false;
1094 	}
1095 }
1096 
1097 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1098 {
1099 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1100 	int ret;
1101 
1102 	if (!port_priv->event_mode)
1103 		return;
1104 
1105 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1106 	if (ret) {
1107 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1108 		return;
1109 	}
1110 
1111 	port_priv->event_mode = false;
1112 }
1113 
1114 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1115 {
1116 	bool iflag_change, cc_change;
1117 
1118 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1119 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1120 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1121 
1122 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1123 }
1124 
1125 static void cp210x_set_flow_control(struct tty_struct *tty,
1126 				    struct usb_serial_port *port,
1127 				    const struct ktermios *old_termios)
1128 {
1129 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1130 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1131 	struct cp210x_special_chars chars;
1132 	struct cp210x_flow_ctl flow_ctl;
1133 	u32 flow_repl;
1134 	u32 ctl_hs;
1135 	bool crtscts;
1136 	int ret;
1137 
1138 	/*
1139 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1140 	 * CP2102N_E104). Report back that flow control is not supported.
1141 	 */
1142 	if (priv->no_flow_control) {
1143 		tty->termios.c_cflag &= ~CRTSCTS;
1144 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1145 	}
1146 
1147 	if (old_termios &&
1148 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1149 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1150 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1151 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1152 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1153 		return;
1154 	}
1155 
1156 	if (I_IXON(tty) || I_IXOFF(tty)) {
1157 		memset(&chars, 0, sizeof(chars));
1158 
1159 		chars.bXonChar = START_CHAR(tty);
1160 		chars.bXoffChar = STOP_CHAR(tty);
1161 
1162 		ret = cp210x_write_reg_block(port, CP210X_SET_CHARS, &chars,
1163 				sizeof(chars));
1164 		if (ret) {
1165 			dev_err(&port->dev, "failed to set special chars: %d\n",
1166 					ret);
1167 		}
1168 	}
1169 
1170 	mutex_lock(&port_priv->mutex);
1171 
1172 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1173 			sizeof(flow_ctl));
1174 	if (ret)
1175 		goto out_unlock;
1176 
1177 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1178 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1179 
1180 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1181 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1182 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1183 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1184 	if (port_priv->dtr)
1185 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1186 	else
1187 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1188 
1189 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1190 	if (C_CRTSCTS(tty)) {
1191 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1192 		if (port_priv->rts)
1193 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1194 		else
1195 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1196 		crtscts = true;
1197 	} else {
1198 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1199 		if (port_priv->rts)
1200 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1201 		else
1202 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1203 		crtscts = false;
1204 	}
1205 
1206 	if (I_IXOFF(tty)) {
1207 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1208 
1209 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1210 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1211 	} else {
1212 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1213 	}
1214 
1215 	if (I_IXON(tty))
1216 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1217 	else
1218 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1219 
1220 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1221 			ctl_hs, flow_repl);
1222 
1223 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1224 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1225 
1226 	ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1227 			sizeof(flow_ctl));
1228 	if (ret)
1229 		goto out_unlock;
1230 
1231 	port_priv->crtscts = crtscts;
1232 out_unlock:
1233 	mutex_unlock(&port_priv->mutex);
1234 }
1235 
1236 static void cp210x_set_termios(struct tty_struct *tty,
1237 		               struct usb_serial_port *port,
1238 		               const struct ktermios *old_termios)
1239 {
1240 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1241 	u16 bits;
1242 	int ret;
1243 
1244 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1245 		return;
1246 
1247 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1248 		cp210x_change_speed(tty, port, old_termios);
1249 
1250 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1251 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1252 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1253 		tty->termios.c_cflag |= CS8;
1254 	}
1255 
1256 	bits = 0;
1257 
1258 	switch (C_CSIZE(tty)) {
1259 	case CS5:
1260 		bits |= BITS_DATA_5;
1261 		break;
1262 	case CS6:
1263 		bits |= BITS_DATA_6;
1264 		break;
1265 	case CS7:
1266 		bits |= BITS_DATA_7;
1267 		break;
1268 	case CS8:
1269 	default:
1270 		bits |= BITS_DATA_8;
1271 		break;
1272 	}
1273 
1274 	if (C_PARENB(tty)) {
1275 		if (C_CMSPAR(tty)) {
1276 			if (C_PARODD(tty))
1277 				bits |= BITS_PARITY_MARK;
1278 			else
1279 				bits |= BITS_PARITY_SPACE;
1280 		} else {
1281 			if (C_PARODD(tty))
1282 				bits |= BITS_PARITY_ODD;
1283 			else
1284 				bits |= BITS_PARITY_EVEN;
1285 		}
1286 	}
1287 
1288 	if (C_CSTOPB(tty))
1289 		bits |= BITS_STOP_2;
1290 	else
1291 		bits |= BITS_STOP_1;
1292 
1293 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1294 	if (ret)
1295 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1296 
1297 	cp210x_set_flow_control(tty, port, old_termios);
1298 
1299 	/*
1300 	 * Enable event-insertion mode only if input parity checking is
1301 	 * enabled for now.
1302 	 */
1303 	if (I_INPCK(tty))
1304 		cp210x_enable_event_mode(port);
1305 	else
1306 		cp210x_disable_event_mode(port);
1307 }
1308 
1309 static int cp210x_tiocmset(struct tty_struct *tty,
1310 		unsigned int set, unsigned int clear)
1311 {
1312 	struct usb_serial_port *port = tty->driver_data;
1313 	return cp210x_tiocmset_port(port, set, clear);
1314 }
1315 
1316 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1317 		unsigned int set, unsigned int clear)
1318 {
1319 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1320 	struct cp210x_flow_ctl flow_ctl;
1321 	u32 ctl_hs, flow_repl;
1322 	u16 control = 0;
1323 	int ret;
1324 
1325 	mutex_lock(&port_priv->mutex);
1326 
1327 	if (set & TIOCM_RTS) {
1328 		port_priv->rts = true;
1329 		control |= CONTROL_RTS;
1330 		control |= CONTROL_WRITE_RTS;
1331 	}
1332 	if (set & TIOCM_DTR) {
1333 		port_priv->dtr = true;
1334 		control |= CONTROL_DTR;
1335 		control |= CONTROL_WRITE_DTR;
1336 	}
1337 	if (clear & TIOCM_RTS) {
1338 		port_priv->rts = false;
1339 		control &= ~CONTROL_RTS;
1340 		control |= CONTROL_WRITE_RTS;
1341 	}
1342 	if (clear & TIOCM_DTR) {
1343 		port_priv->dtr = false;
1344 		control &= ~CONTROL_DTR;
1345 		control |= CONTROL_WRITE_DTR;
1346 	}
1347 
1348 	/*
1349 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1350 	 * flow control is enabled.
1351 	 */
1352 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1353 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1354 				sizeof(flow_ctl));
1355 		if (ret)
1356 			goto out_unlock;
1357 
1358 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1359 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1360 
1361 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1362 		if (port_priv->dtr)
1363 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1364 		else
1365 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1366 
1367 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1368 		if (port_priv->rts)
1369 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1370 		else
1371 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1372 
1373 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1374 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1375 
1376 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1377 				__func__, ctl_hs, flow_repl);
1378 
1379 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1380 				sizeof(flow_ctl));
1381 	} else {
1382 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1383 
1384 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1385 	}
1386 out_unlock:
1387 	mutex_unlock(&port_priv->mutex);
1388 
1389 	return ret;
1390 }
1391 
1392 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1393 {
1394 	if (on)
1395 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1396 	else
1397 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1398 }
1399 
1400 static int cp210x_tiocmget(struct tty_struct *tty)
1401 {
1402 	struct usb_serial_port *port = tty->driver_data;
1403 	u8 control;
1404 	int result;
1405 
1406 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1407 	if (result)
1408 		return result;
1409 
1410 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1411 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1412 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1413 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1414 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1415 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1416 
1417 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1418 
1419 	return result;
1420 }
1421 
1422 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1423 {
1424 	struct usb_serial_port *port = tty->driver_data;
1425 	u16 state;
1426 
1427 	if (break_state == 0)
1428 		state = BREAK_OFF;
1429 	else
1430 		state = BREAK_ON;
1431 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1432 		state == BREAK_OFF ? "off" : "on");
1433 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1434 }
1435 
1436 #ifdef CONFIG_GPIOLIB
1437 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1438 {
1439 	struct usb_serial *serial = gpiochip_get_data(gc);
1440 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1441 	u8 req_type;
1442 	u16 mask;
1443 	int result;
1444 	int len;
1445 
1446 	result = usb_autopm_get_interface(serial->interface);
1447 	if (result)
1448 		return result;
1449 
1450 	switch (priv->partnum) {
1451 	case CP210X_PARTNUM_CP2105:
1452 		req_type = REQTYPE_INTERFACE_TO_HOST;
1453 		len = 1;
1454 		break;
1455 	case CP210X_PARTNUM_CP2108:
1456 		req_type = REQTYPE_INTERFACE_TO_HOST;
1457 		len = 2;
1458 		break;
1459 	default:
1460 		req_type = REQTYPE_DEVICE_TO_HOST;
1461 		len = 1;
1462 		break;
1463 	}
1464 
1465 	mask = 0;
1466 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1467 					  &mask, len);
1468 
1469 	usb_autopm_put_interface(serial->interface);
1470 
1471 	if (result < 0)
1472 		return result;
1473 
1474 	le16_to_cpus(&mask);
1475 
1476 	return !!(mask & BIT(gpio));
1477 }
1478 
1479 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1480 {
1481 	struct usb_serial *serial = gpiochip_get_data(gc);
1482 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1483 	struct cp210x_gpio_write16 buf16;
1484 	struct cp210x_gpio_write buf;
1485 	u16 mask, state;
1486 	u16 wIndex;
1487 	int result;
1488 
1489 	if (value == 1)
1490 		state = BIT(gpio);
1491 	else
1492 		state = 0;
1493 
1494 	mask = BIT(gpio);
1495 
1496 	result = usb_autopm_get_interface(serial->interface);
1497 	if (result)
1498 		goto out;
1499 
1500 	switch (priv->partnum) {
1501 	case CP210X_PARTNUM_CP2105:
1502 		buf.mask = (u8)mask;
1503 		buf.state = (u8)state;
1504 		result = cp210x_write_vendor_block(serial,
1505 						   REQTYPE_HOST_TO_INTERFACE,
1506 						   CP210X_WRITE_LATCH, &buf,
1507 						   sizeof(buf));
1508 		break;
1509 	case CP210X_PARTNUM_CP2108:
1510 		buf16.mask = cpu_to_le16(mask);
1511 		buf16.state = cpu_to_le16(state);
1512 		result = cp210x_write_vendor_block(serial,
1513 						   REQTYPE_HOST_TO_INTERFACE,
1514 						   CP210X_WRITE_LATCH, &buf16,
1515 						   sizeof(buf16));
1516 		break;
1517 	default:
1518 		wIndex = state << 8 | mask;
1519 		result = usb_control_msg(serial->dev,
1520 					 usb_sndctrlpipe(serial->dev, 0),
1521 					 CP210X_VENDOR_SPECIFIC,
1522 					 REQTYPE_HOST_TO_DEVICE,
1523 					 CP210X_WRITE_LATCH,
1524 					 wIndex,
1525 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1526 		break;
1527 	}
1528 
1529 	usb_autopm_put_interface(serial->interface);
1530 out:
1531 	if (result < 0) {
1532 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1533 				result);
1534 	}
1535 }
1536 
1537 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1538 {
1539 	struct usb_serial *serial = gpiochip_get_data(gc);
1540 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1541 
1542 	return priv->gpio_input & BIT(gpio);
1543 }
1544 
1545 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1546 {
1547 	struct usb_serial *serial = gpiochip_get_data(gc);
1548 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1549 
1550 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1551 		/* hardware does not support an input mode */
1552 		return -ENOTSUPP;
1553 	}
1554 
1555 	/* push-pull pins cannot be changed to be inputs */
1556 	if (priv->gpio_pushpull & BIT(gpio))
1557 		return -EINVAL;
1558 
1559 	/* make sure to release pin if it is being driven low */
1560 	cp210x_gpio_set(gc, gpio, 1);
1561 
1562 	priv->gpio_input |= BIT(gpio);
1563 
1564 	return 0;
1565 }
1566 
1567 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1568 					int value)
1569 {
1570 	struct usb_serial *serial = gpiochip_get_data(gc);
1571 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1572 
1573 	priv->gpio_input &= ~BIT(gpio);
1574 	cp210x_gpio_set(gc, gpio, value);
1575 
1576 	return 0;
1577 }
1578 
1579 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1580 				  unsigned long config)
1581 {
1582 	struct usb_serial *serial = gpiochip_get_data(gc);
1583 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1584 	enum pin_config_param param = pinconf_to_config_param(config);
1585 
1586 	/* Succeed only if in correct mode (this can't be set at runtime) */
1587 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1588 	    (priv->gpio_pushpull & BIT(gpio)))
1589 		return 0;
1590 
1591 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1592 	    !(priv->gpio_pushpull & BIT(gpio)))
1593 		return 0;
1594 
1595 	return -ENOTSUPP;
1596 }
1597 
1598 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1599 		unsigned long *valid_mask, unsigned int ngpios)
1600 {
1601 	struct usb_serial *serial = gpiochip_get_data(gc);
1602 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1603 	struct device *dev = &serial->interface->dev;
1604 	unsigned long altfunc_mask = priv->gpio_altfunc;
1605 
1606 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1607 
1608 	if (bitmap_empty(valid_mask, ngpios))
1609 		dev_dbg(dev, "no pin configured for GPIO\n");
1610 	else
1611 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1612 				valid_mask);
1613 	return 0;
1614 }
1615 
1616 /*
1617  * This function is for configuring GPIO using shared pins, where other signals
1618  * are made unavailable by configuring the use of GPIO. This is believed to be
1619  * only applicable to the cp2105 at this point, the other devices supported by
1620  * this driver that provide GPIO do so in a way that does not impact other
1621  * signals and are thus expected to have very different initialisation.
1622  */
1623 static int cp2105_gpioconf_init(struct usb_serial *serial)
1624 {
1625 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1626 	struct cp210x_pin_mode mode;
1627 	struct cp210x_dual_port_config config;
1628 	u8 intf_num = cp210x_interface_num(serial);
1629 	u8 iface_config;
1630 	int result;
1631 
1632 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1633 					  CP210X_GET_DEVICEMODE, &mode,
1634 					  sizeof(mode));
1635 	if (result < 0)
1636 		return result;
1637 
1638 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1639 					  CP210X_GET_PORTCONFIG, &config,
1640 					  sizeof(config));
1641 	if (result < 0)
1642 		return result;
1643 
1644 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1645 	if (intf_num == 0) {
1646 		priv->gc.ngpio = 2;
1647 
1648 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1649 			/* mark all GPIOs of this interface as reserved */
1650 			priv->gpio_altfunc = 0xff;
1651 			return 0;
1652 		}
1653 
1654 		iface_config = config.eci_cfg;
1655 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1656 						CP210X_ECI_GPIO_MODE_MASK) >>
1657 						CP210X_ECI_GPIO_MODE_OFFSET);
1658 	} else if (intf_num == 1) {
1659 		priv->gc.ngpio = 3;
1660 
1661 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1662 			/* mark all GPIOs of this interface as reserved */
1663 			priv->gpio_altfunc = 0xff;
1664 			return 0;
1665 		}
1666 
1667 		iface_config = config.sci_cfg;
1668 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1669 						CP210X_SCI_GPIO_MODE_MASK) >>
1670 						CP210X_SCI_GPIO_MODE_OFFSET);
1671 	} else {
1672 		return -ENODEV;
1673 	}
1674 
1675 	/* mark all pins which are not in GPIO mode */
1676 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1677 		priv->gpio_altfunc |= BIT(0);
1678 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1679 			CP2105_GPIO1_RS485_MODE))
1680 		priv->gpio_altfunc |= BIT(1);
1681 
1682 	/* driver implementation for CP2105 only supports outputs */
1683 	priv->gpio_input = 0;
1684 
1685 	return 0;
1686 }
1687 
1688 static int cp2104_gpioconf_init(struct usb_serial *serial)
1689 {
1690 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1691 	struct cp210x_single_port_config config;
1692 	u8 iface_config;
1693 	u8 gpio_latch;
1694 	int result;
1695 	u8 i;
1696 
1697 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1698 					  CP210X_GET_PORTCONFIG, &config,
1699 					  sizeof(config));
1700 	if (result < 0)
1701 		return result;
1702 
1703 	priv->gc.ngpio = 4;
1704 
1705 	iface_config = config.device_cfg;
1706 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1707 					CP210X_GPIO_MODE_MASK) >>
1708 					CP210X_GPIO_MODE_OFFSET);
1709 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1710 					CP210X_GPIO_MODE_MASK) >>
1711 					CP210X_GPIO_MODE_OFFSET);
1712 
1713 	/* mark all pins which are not in GPIO mode */
1714 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1715 		priv->gpio_altfunc |= BIT(0);
1716 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1717 		priv->gpio_altfunc |= BIT(1);
1718 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1719 		priv->gpio_altfunc |= BIT(2);
1720 
1721 	/*
1722 	 * Like CP2102N, CP2104 has also no strict input and output pin
1723 	 * modes.
1724 	 * Do the same input mode emulation as CP2102N.
1725 	 */
1726 	for (i = 0; i < priv->gc.ngpio; ++i) {
1727 		/*
1728 		 * Set direction to "input" iff pin is open-drain and reset
1729 		 * value is 1.
1730 		 */
1731 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1732 			priv->gpio_input |= BIT(i);
1733 	}
1734 
1735 	return 0;
1736 }
1737 
1738 static int cp2108_gpio_init(struct usb_serial *serial)
1739 {
1740 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1741 	struct cp210x_quad_port_config config;
1742 	u16 gpio_latch;
1743 	int result;
1744 	u8 i;
1745 
1746 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1747 					  CP210X_GET_PORTCONFIG, &config,
1748 					  sizeof(config));
1749 	if (result < 0)
1750 		return result;
1751 
1752 	priv->gc.ngpio = 16;
1753 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1754 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1755 
1756 	/*
1757 	 * Mark all pins which are not in GPIO mode.
1758 	 *
1759 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1760 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1761 	 *
1762 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1763 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1764 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1765 	 */
1766 	for (i = 0; i < 4; i++) {
1767 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1768 			priv->gpio_altfunc |= BIT(i * 4);
1769 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1770 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1771 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1772 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1773 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1774 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1775 	}
1776 
1777 	/*
1778 	 * Like CP2102N, CP2108 has also no strict input and output pin
1779 	 * modes. Do the same input mode emulation as CP2102N.
1780 	 */
1781 	for (i = 0; i < priv->gc.ngpio; ++i) {
1782 		/*
1783 		 * Set direction to "input" iff pin is open-drain and reset
1784 		 * value is 1.
1785 		 */
1786 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1787 			priv->gpio_input |= BIT(i);
1788 	}
1789 
1790 	return 0;
1791 }
1792 
1793 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1794 {
1795 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1796 	const u16 config_size = 0x02a6;
1797 	u8 gpio_rst_latch;
1798 	u8 config_version;
1799 	u8 gpio_pushpull;
1800 	u8 *config_buf;
1801 	u8 gpio_latch;
1802 	u8 gpio_ctrl;
1803 	int result;
1804 	u8 i;
1805 
1806 	/*
1807 	 * Retrieve device configuration from the device.
1808 	 * The array received contains all customization settings done at the
1809 	 * factory/manufacturer. Format of the array is documented at the
1810 	 * time of writing at:
1811 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1812 	 */
1813 	config_buf = kmalloc(config_size, GFP_KERNEL);
1814 	if (!config_buf)
1815 		return -ENOMEM;
1816 
1817 	result = cp210x_read_vendor_block(serial,
1818 					  REQTYPE_DEVICE_TO_HOST,
1819 					  CP210X_READ_2NCONFIG,
1820 					  config_buf,
1821 					  config_size);
1822 	if (result < 0) {
1823 		kfree(config_buf);
1824 		return result;
1825 	}
1826 
1827 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1828 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1829 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1830 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1831 
1832 	kfree(config_buf);
1833 
1834 	/* Make sure this is a config format we understand. */
1835 	if (config_version != 0x01)
1836 		return -ENOTSUPP;
1837 
1838 	priv->gc.ngpio = 4;
1839 
1840 	/*
1841 	 * Get default pin states after reset. Needed so we can determine
1842 	 * the direction of an open-drain pin.
1843 	 */
1844 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1845 
1846 	/* 0 indicates open-drain mode, 1 is push-pull */
1847 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1848 
1849 	/* 0 indicates GPIO mode, 1 is alternate function */
1850 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1851 		/* QFN20 is special... */
1852 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1853 			priv->gpio_altfunc |= BIT(0);
1854 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1855 			priv->gpio_altfunc |= BIT(1);
1856 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1857 			priv->gpio_altfunc |= BIT(2);
1858 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1859 			priv->gpio_altfunc |= BIT(3);
1860 	} else {
1861 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1862 	}
1863 
1864 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1865 		/*
1866 		 * For the QFN28 package, GPIO4-6 are controlled by
1867 		 * the low three bits of the mode/latch fields.
1868 		 * Contrary to the document linked above, the bits for
1869 		 * the SUSPEND pins are elsewhere.  No alternate
1870 		 * function is available for these pins.
1871 		 */
1872 		priv->gc.ngpio = 7;
1873 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1874 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1875 	}
1876 
1877 	/*
1878 	 * The CP2102N does not strictly has input and output pin modes,
1879 	 * it only knows open-drain and push-pull modes which is set at
1880 	 * factory. An open-drain pin can function both as an
1881 	 * input or an output. We emulate input mode for open-drain pins
1882 	 * by making sure they are not driven low, and we do not allow
1883 	 * push-pull pins to be set as an input.
1884 	 */
1885 	for (i = 0; i < priv->gc.ngpio; ++i) {
1886 		/*
1887 		 * Set direction to "input" iff pin is open-drain and reset
1888 		 * value is 1.
1889 		 */
1890 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1891 			priv->gpio_input |= BIT(i);
1892 	}
1893 
1894 	return 0;
1895 }
1896 
1897 static int cp210x_gpio_init(struct usb_serial *serial)
1898 {
1899 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1900 	int result;
1901 
1902 	switch (priv->partnum) {
1903 	case CP210X_PARTNUM_CP2104:
1904 		result = cp2104_gpioconf_init(serial);
1905 		break;
1906 	case CP210X_PARTNUM_CP2105:
1907 		result = cp2105_gpioconf_init(serial);
1908 		break;
1909 	case CP210X_PARTNUM_CP2108:
1910 		/*
1911 		 * The GPIOs are not tied to any specific port so only register
1912 		 * once for interface 0.
1913 		 */
1914 		if (cp210x_interface_num(serial) != 0)
1915 			return 0;
1916 		result = cp2108_gpio_init(serial);
1917 		break;
1918 	case CP210X_PARTNUM_CP2102N_QFN28:
1919 	case CP210X_PARTNUM_CP2102N_QFN24:
1920 	case CP210X_PARTNUM_CP2102N_QFN20:
1921 		result = cp2102n_gpioconf_init(serial);
1922 		break;
1923 	default:
1924 		return 0;
1925 	}
1926 
1927 	if (result < 0)
1928 		return result;
1929 
1930 	priv->gc.label = "cp210x";
1931 	priv->gc.get_direction = cp210x_gpio_direction_get;
1932 	priv->gc.direction_input = cp210x_gpio_direction_input;
1933 	priv->gc.direction_output = cp210x_gpio_direction_output;
1934 	priv->gc.get = cp210x_gpio_get;
1935 	priv->gc.set = cp210x_gpio_set;
1936 	priv->gc.set_config = cp210x_gpio_set_config;
1937 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1938 	priv->gc.owner = THIS_MODULE;
1939 	priv->gc.parent = &serial->interface->dev;
1940 	priv->gc.base = -1;
1941 	priv->gc.can_sleep = true;
1942 
1943 	result = gpiochip_add_data(&priv->gc, serial);
1944 	if (!result)
1945 		priv->gpio_registered = true;
1946 
1947 	return result;
1948 }
1949 
1950 static void cp210x_gpio_remove(struct usb_serial *serial)
1951 {
1952 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1953 
1954 	if (priv->gpio_registered) {
1955 		gpiochip_remove(&priv->gc);
1956 		priv->gpio_registered = false;
1957 	}
1958 }
1959 
1960 #else
1961 
1962 static int cp210x_gpio_init(struct usb_serial *serial)
1963 {
1964 	return 0;
1965 }
1966 
1967 static void cp210x_gpio_remove(struct usb_serial *serial)
1968 {
1969 	/* Nothing to do */
1970 }
1971 
1972 #endif
1973 
1974 static int cp210x_port_probe(struct usb_serial_port *port)
1975 {
1976 	struct usb_serial *serial = port->serial;
1977 	struct cp210x_port_private *port_priv;
1978 
1979 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1980 	if (!port_priv)
1981 		return -ENOMEM;
1982 
1983 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1984 	mutex_init(&port_priv->mutex);
1985 
1986 	usb_set_serial_port_data(port, port_priv);
1987 
1988 	return 0;
1989 }
1990 
1991 static void cp210x_port_remove(struct usb_serial_port *port)
1992 {
1993 	struct cp210x_port_private *port_priv;
1994 
1995 	port_priv = usb_get_serial_port_data(port);
1996 	kfree(port_priv);
1997 }
1998 
1999 static void cp210x_init_max_speed(struct usb_serial *serial)
2000 {
2001 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2002 	bool use_actual_rate = false;
2003 	speed_t min = 300;
2004 	speed_t max;
2005 
2006 	switch (priv->partnum) {
2007 	case CP210X_PARTNUM_CP2101:
2008 		max = 921600;
2009 		break;
2010 	case CP210X_PARTNUM_CP2102:
2011 	case CP210X_PARTNUM_CP2103:
2012 		max = 1000000;
2013 		break;
2014 	case CP210X_PARTNUM_CP2104:
2015 		use_actual_rate = true;
2016 		max = 2000000;
2017 		break;
2018 	case CP210X_PARTNUM_CP2108:
2019 		max = 2000000;
2020 		break;
2021 	case CP210X_PARTNUM_CP2105:
2022 		if (cp210x_interface_num(serial) == 0) {
2023 			use_actual_rate = true;
2024 			max = 2000000;	/* ECI */
2025 		} else {
2026 			min = 2400;
2027 			max = 921600;	/* SCI */
2028 		}
2029 		break;
2030 	case CP210X_PARTNUM_CP2102N_QFN28:
2031 	case CP210X_PARTNUM_CP2102N_QFN24:
2032 	case CP210X_PARTNUM_CP2102N_QFN20:
2033 		use_actual_rate = true;
2034 		max = 3000000;
2035 		break;
2036 	default:
2037 		max = 2000000;
2038 		break;
2039 	}
2040 
2041 	priv->min_speed = min;
2042 	priv->max_speed = max;
2043 	priv->use_actual_rate = use_actual_rate;
2044 }
2045 
2046 static void cp2102_determine_quirks(struct usb_serial *serial)
2047 {
2048 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2049 	u8 *buf;
2050 	int ret;
2051 
2052 	buf = kmalloc(2, GFP_KERNEL);
2053 	if (!buf)
2054 		return;
2055 	/*
2056 	 * Some (possibly counterfeit) CP2102 do not support event-insertion
2057 	 * mode and respond differently to malformed vendor requests.
2058 	 * Specifically, they return one instead of two bytes when sent a
2059 	 * two-byte part-number request.
2060 	 */
2061 	ret = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
2062 			CP210X_VENDOR_SPECIFIC, REQTYPE_DEVICE_TO_HOST,
2063 			CP210X_GET_PARTNUM, 0, buf, 2, USB_CTRL_GET_TIMEOUT);
2064 	if (ret == 1) {
2065 		dev_dbg(&serial->interface->dev,
2066 				"device does not support event-insertion mode\n");
2067 		priv->no_event_mode = true;
2068 	}
2069 
2070 	kfree(buf);
2071 }
2072 
2073 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2074 {
2075 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2076 	u8 ver[3];
2077 	int ret;
2078 
2079 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2080 			ver, sizeof(ver));
2081 	if (ret)
2082 		return ret;
2083 
2084 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2085 			ver[0], ver[1], ver[2]);
2086 
2087 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2088 
2089 	return 0;
2090 }
2091 
2092 static void cp210x_determine_type(struct usb_serial *serial)
2093 {
2094 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2095 	int ret;
2096 
2097 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2098 			CP210X_GET_PARTNUM, &priv->partnum,
2099 			sizeof(priv->partnum));
2100 	if (ret < 0) {
2101 		dev_warn(&serial->interface->dev,
2102 				"querying part number failed\n");
2103 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2104 		return;
2105 	}
2106 
2107 	dev_dbg(&serial->interface->dev, "partnum = 0x%02x\n", priv->partnum);
2108 
2109 	switch (priv->partnum) {
2110 	case CP210X_PARTNUM_CP2102:
2111 		cp2102_determine_quirks(serial);
2112 		break;
2113 	case CP210X_PARTNUM_CP2105:
2114 	case CP210X_PARTNUM_CP2108:
2115 		cp210x_get_fw_version(serial, CP210X_GET_FW_VER);
2116 		break;
2117 	case CP210X_PARTNUM_CP2102N_QFN28:
2118 	case CP210X_PARTNUM_CP2102N_QFN24:
2119 	case CP210X_PARTNUM_CP2102N_QFN20:
2120 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2121 		if (ret)
2122 			break;
2123 		if (priv->fw_version <= 0x10004)
2124 			priv->no_flow_control = true;
2125 		break;
2126 	default:
2127 		break;
2128 	}
2129 }
2130 
2131 static int cp210x_attach(struct usb_serial *serial)
2132 {
2133 	int result;
2134 	struct cp210x_serial_private *priv;
2135 
2136 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2137 	if (!priv)
2138 		return -ENOMEM;
2139 
2140 	usb_set_serial_data(serial, priv);
2141 
2142 	cp210x_determine_type(serial);
2143 	cp210x_init_max_speed(serial);
2144 
2145 	result = cp210x_gpio_init(serial);
2146 	if (result < 0) {
2147 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2148 				result);
2149 	}
2150 
2151 	return 0;
2152 }
2153 
2154 static void cp210x_disconnect(struct usb_serial *serial)
2155 {
2156 	cp210x_gpio_remove(serial);
2157 }
2158 
2159 static void cp210x_release(struct usb_serial *serial)
2160 {
2161 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2162 
2163 	cp210x_gpio_remove(serial);
2164 
2165 	kfree(priv);
2166 }
2167 
2168 module_usb_serial_driver(serial_drivers, id_table);
2169 
2170 MODULE_DESCRIPTION(DRIVER_DESC);
2171 MODULE_LICENSE("GPL v2");
2172