xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision aa0dc6a7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Silicon Laboratories CP210x USB to RS232 serial adaptor driver
4  *
5  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
6  * Copyright (C) 2010-2021 Johan Hovold (johan@kernel.org)
7  *
8  * Support to set flow control line levels using TIOCMGET and TIOCMSET
9  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
10  * control thanks to Munir Nassar nassarmu@real-time.com
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/module.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/gpio/driver.h>
23 #include <linux/bitops.h>
24 #include <linux/mutex.h>
25 
26 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
27 
28 /*
29  * Function Prototypes
30  */
31 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
32 static void cp210x_close(struct usb_serial_port *);
33 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
34 							struct ktermios *);
35 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
36 							struct ktermios*);
37 static bool cp210x_tx_empty(struct usb_serial_port *port);
38 static int cp210x_tiocmget(struct tty_struct *);
39 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
40 static int cp210x_tiocmset_port(struct usb_serial_port *port,
41 		unsigned int, unsigned int);
42 static void cp210x_break_ctl(struct tty_struct *, int);
43 static int cp210x_attach(struct usb_serial *);
44 static void cp210x_disconnect(struct usb_serial *);
45 static void cp210x_release(struct usb_serial *);
46 static int cp210x_port_probe(struct usb_serial_port *);
47 static void cp210x_port_remove(struct usb_serial_port *);
48 static void cp210x_dtr_rts(struct usb_serial_port *port, int on);
49 static void cp210x_process_read_urb(struct urb *urb);
50 static void cp210x_enable_event_mode(struct usb_serial_port *port);
51 static void cp210x_disable_event_mode(struct usb_serial_port *port);
52 
53 static const struct usb_device_id id_table[] = {
54 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
55 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
56 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
57 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
58 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
59 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
60 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
61 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
62 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
63 	{ USB_DEVICE(0x0988, 0x0578) }, /* Teraoka AD2000 */
64 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
65 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
66 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
67 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
68 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
69 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
71 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
72 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
73 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
74 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
75 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
76 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
77 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
78 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
79 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
80 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
81 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
82 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
83 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
84 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
85 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
86 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
87 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
88 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
89 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
90 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
91 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
92 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
93 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
94 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
95 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
96 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
97 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
98 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
99 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
100 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
104 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
105 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
106 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
107 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
108 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
109 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
110 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
111 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
112 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
113 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
114 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
115 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
116 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
117 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
118 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
119 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
120 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
121 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
122 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
123 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
124 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
125 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
126 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
127 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
128 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
129 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
130 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
131 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
132 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
133 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
134 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
135 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
136 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
137 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
138 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
139 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
140 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
141 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
142 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
143 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
144 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
145 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
146 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
147 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
148 	{ USB_DEVICE(0x10C4, 0x88D8) }, /* Acuity Brands nLight Air Adapter */
149 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
150 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
151 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
152 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
153 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
154 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
155 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
156 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
157 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
158 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
159 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
160 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
161 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
162 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
163 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
164 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
165 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
166 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
167 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
168 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
169 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
170 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
171 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
172 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
173 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
174 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
175 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
176 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
177 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
178 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
179 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
180 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
181 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
182 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
183 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
184 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
185 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
186 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
187 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
188 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
189 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
190 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
191 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
192 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
193 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
194 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
195 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
196 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
197 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
198 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
199 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
200 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
201 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
202 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
203 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
204 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
205 	{ USB_DEVICE(0x1901, 0x0197) }, /* GE CS1000 Display serial interface */
206 	{ USB_DEVICE(0x1901, 0x0198) }, /* GE CS1000 M.2 Key E serial interface */
207 	{ USB_DEVICE(0x199B, 0xBA30) }, /* LORD WSDA-200-USB */
208 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
209 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
210 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
211 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
212 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
213 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
214 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
215 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
216 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
217 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
218 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
219 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
220 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
221 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
222 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
223 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
224 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
225 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
227 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
228 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
229 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
230 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
231 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
232 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
233 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
234 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
235 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
236 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
237 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
238 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
239 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
240 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
241 	{ } /* Terminating Entry */
242 };
243 
244 MODULE_DEVICE_TABLE(usb, id_table);
245 
246 struct cp210x_serial_private {
247 #ifdef CONFIG_GPIOLIB
248 	struct gpio_chip	gc;
249 	bool			gpio_registered;
250 	u16			gpio_pushpull;
251 	u16			gpio_altfunc;
252 	u16			gpio_input;
253 #endif
254 	u8			partnum;
255 	u32			fw_version;
256 	speed_t			min_speed;
257 	speed_t			max_speed;
258 	bool			use_actual_rate;
259 	bool			no_flow_control;
260 };
261 
262 enum cp210x_event_state {
263 	ES_DATA,
264 	ES_ESCAPE,
265 	ES_LSR,
266 	ES_LSR_DATA_0,
267 	ES_LSR_DATA_1,
268 	ES_MSR
269 };
270 
271 struct cp210x_port_private {
272 	u8			bInterfaceNumber;
273 	bool			event_mode;
274 	enum cp210x_event_state event_state;
275 	u8			lsr;
276 
277 	struct mutex		mutex;
278 	bool			crtscts;
279 	bool			dtr;
280 	bool			rts;
281 };
282 
283 static struct usb_serial_driver cp210x_device = {
284 	.driver = {
285 		.owner =	THIS_MODULE,
286 		.name =		"cp210x",
287 	},
288 	.id_table		= id_table,
289 	.num_ports		= 1,
290 	.bulk_in_size		= 256,
291 	.bulk_out_size		= 256,
292 	.open			= cp210x_open,
293 	.close			= cp210x_close,
294 	.break_ctl		= cp210x_break_ctl,
295 	.set_termios		= cp210x_set_termios,
296 	.tx_empty		= cp210x_tx_empty,
297 	.throttle		= usb_serial_generic_throttle,
298 	.unthrottle		= usb_serial_generic_unthrottle,
299 	.tiocmget		= cp210x_tiocmget,
300 	.tiocmset		= cp210x_tiocmset,
301 	.get_icount		= usb_serial_generic_get_icount,
302 	.attach			= cp210x_attach,
303 	.disconnect		= cp210x_disconnect,
304 	.release		= cp210x_release,
305 	.port_probe		= cp210x_port_probe,
306 	.port_remove		= cp210x_port_remove,
307 	.dtr_rts		= cp210x_dtr_rts,
308 	.process_read_urb	= cp210x_process_read_urb,
309 };
310 
311 static struct usb_serial_driver * const serial_drivers[] = {
312 	&cp210x_device, NULL
313 };
314 
315 /* Config request types */
316 #define REQTYPE_HOST_TO_INTERFACE	0x41
317 #define REQTYPE_INTERFACE_TO_HOST	0xc1
318 #define REQTYPE_HOST_TO_DEVICE	0x40
319 #define REQTYPE_DEVICE_TO_HOST	0xc0
320 
321 /* Config request codes */
322 #define CP210X_IFC_ENABLE	0x00
323 #define CP210X_SET_BAUDDIV	0x01
324 #define CP210X_GET_BAUDDIV	0x02
325 #define CP210X_SET_LINE_CTL	0x03
326 #define CP210X_GET_LINE_CTL	0x04
327 #define CP210X_SET_BREAK	0x05
328 #define CP210X_IMM_CHAR		0x06
329 #define CP210X_SET_MHS		0x07
330 #define CP210X_GET_MDMSTS	0x08
331 #define CP210X_SET_XON		0x09
332 #define CP210X_SET_XOFF		0x0A
333 #define CP210X_SET_EVENTMASK	0x0B
334 #define CP210X_GET_EVENTMASK	0x0C
335 #define CP210X_SET_CHAR		0x0D
336 #define CP210X_GET_CHARS	0x0E
337 #define CP210X_GET_PROPS	0x0F
338 #define CP210X_GET_COMM_STATUS	0x10
339 #define CP210X_RESET		0x11
340 #define CP210X_PURGE		0x12
341 #define CP210X_SET_FLOW		0x13
342 #define CP210X_GET_FLOW		0x14
343 #define CP210X_EMBED_EVENTS	0x15
344 #define CP210X_GET_EVENTSTATE	0x16
345 #define CP210X_SET_CHARS	0x19
346 #define CP210X_GET_BAUDRATE	0x1D
347 #define CP210X_SET_BAUDRATE	0x1E
348 #define CP210X_VENDOR_SPECIFIC	0xFF
349 
350 /* CP210X_IFC_ENABLE */
351 #define UART_ENABLE		0x0001
352 #define UART_DISABLE		0x0000
353 
354 /* CP210X_(SET|GET)_BAUDDIV */
355 #define BAUD_RATE_GEN_FREQ	0x384000
356 
357 /* CP210X_(SET|GET)_LINE_CTL */
358 #define BITS_DATA_MASK		0X0f00
359 #define BITS_DATA_5		0X0500
360 #define BITS_DATA_6		0X0600
361 #define BITS_DATA_7		0X0700
362 #define BITS_DATA_8		0X0800
363 #define BITS_DATA_9		0X0900
364 
365 #define BITS_PARITY_MASK	0x00f0
366 #define BITS_PARITY_NONE	0x0000
367 #define BITS_PARITY_ODD		0x0010
368 #define BITS_PARITY_EVEN	0x0020
369 #define BITS_PARITY_MARK	0x0030
370 #define BITS_PARITY_SPACE	0x0040
371 
372 #define BITS_STOP_MASK		0x000f
373 #define BITS_STOP_1		0x0000
374 #define BITS_STOP_1_5		0x0001
375 #define BITS_STOP_2		0x0002
376 
377 /* CP210X_SET_BREAK */
378 #define BREAK_ON		0x0001
379 #define BREAK_OFF		0x0000
380 
381 /* CP210X_(SET_MHS|GET_MDMSTS) */
382 #define CONTROL_DTR		0x0001
383 #define CONTROL_RTS		0x0002
384 #define CONTROL_CTS		0x0010
385 #define CONTROL_DSR		0x0020
386 #define CONTROL_RING		0x0040
387 #define CONTROL_DCD		0x0080
388 #define CONTROL_WRITE_DTR	0x0100
389 #define CONTROL_WRITE_RTS	0x0200
390 
391 /* CP210X_(GET|SET)_CHARS */
392 struct cp210x_special_chars {
393 	u8	bEofChar;
394 	u8	bErrorChar;
395 	u8	bBreakChar;
396 	u8	bEventChar;
397 	u8	bXonChar;
398 	u8	bXoffChar;
399 };
400 
401 /* CP210X_VENDOR_SPECIFIC values */
402 #define CP210X_READ_2NCONFIG	0x000E
403 #define CP210X_GET_FW_VER_2N	0x0010
404 #define CP210X_READ_LATCH	0x00C2
405 #define CP210X_GET_PARTNUM	0x370B
406 #define CP210X_GET_PORTCONFIG	0x370C
407 #define CP210X_GET_DEVICEMODE	0x3711
408 #define CP210X_WRITE_LATCH	0x37E1
409 
410 /* Part number definitions */
411 #define CP210X_PARTNUM_CP2101	0x01
412 #define CP210X_PARTNUM_CP2102	0x02
413 #define CP210X_PARTNUM_CP2103	0x03
414 #define CP210X_PARTNUM_CP2104	0x04
415 #define CP210X_PARTNUM_CP2105	0x05
416 #define CP210X_PARTNUM_CP2108	0x08
417 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
418 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
419 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
420 #define CP210X_PARTNUM_UNKNOWN	0xFF
421 
422 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
423 struct cp210x_comm_status {
424 	__le32   ulErrors;
425 	__le32   ulHoldReasons;
426 	__le32   ulAmountInInQueue;
427 	__le32   ulAmountInOutQueue;
428 	u8       bEofReceived;
429 	u8       bWaitForImmediate;
430 	u8       bReserved;
431 } __packed;
432 
433 /*
434  * CP210X_PURGE - 16 bits passed in wValue of USB request.
435  * SiLabs app note AN571 gives a strange description of the 4 bits:
436  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
437  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
438  */
439 #define PURGE_ALL		0x000f
440 
441 /* CP210X_EMBED_EVENTS */
442 #define CP210X_ESCCHAR		0xec
443 
444 #define CP210X_LSR_OVERRUN	BIT(1)
445 #define CP210X_LSR_PARITY	BIT(2)
446 #define CP210X_LSR_FRAME	BIT(3)
447 #define CP210X_LSR_BREAK	BIT(4)
448 
449 
450 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
451 struct cp210x_flow_ctl {
452 	__le32	ulControlHandshake;
453 	__le32	ulFlowReplace;
454 	__le32	ulXonLimit;
455 	__le32	ulXoffLimit;
456 };
457 
458 /* cp210x_flow_ctl::ulControlHandshake */
459 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
460 #define CP210X_SERIAL_DTR_INACTIVE	(0 << 0)
461 #define CP210X_SERIAL_DTR_ACTIVE	(1 << 0)
462 #define CP210X_SERIAL_DTR_FLOW_CTL	(2 << 0)
463 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
464 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
465 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
466 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
467 
468 /* cp210x_flow_ctl::ulFlowReplace */
469 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
470 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
471 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
472 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
473 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
474 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
475 #define CP210X_SERIAL_RTS_INACTIVE	(0 << 6)
476 #define CP210X_SERIAL_RTS_ACTIVE	(1 << 6)
477 #define CP210X_SERIAL_RTS_FLOW_CTL	(2 << 6)
478 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
479 
480 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
481 struct cp210x_pin_mode {
482 	u8	eci;
483 	u8	sci;
484 };
485 
486 #define CP210X_PIN_MODE_MODEM		0
487 #define CP210X_PIN_MODE_GPIO		BIT(0)
488 
489 /*
490  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
491  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
492  */
493 struct cp210x_dual_port_config {
494 	__le16	gpio_mode;
495 	u8	__pad0[2];
496 	__le16	reset_state;
497 	u8	__pad1[4];
498 	__le16	suspend_state;
499 	u8	sci_cfg;
500 	u8	eci_cfg;
501 	u8	device_cfg;
502 } __packed;
503 
504 /*
505  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
506  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
507  */
508 struct cp210x_single_port_config {
509 	__le16	gpio_mode;
510 	u8	__pad0[2];
511 	__le16	reset_state;
512 	u8	__pad1[4];
513 	__le16	suspend_state;
514 	u8	device_cfg;
515 } __packed;
516 
517 /* GPIO modes */
518 #define CP210X_SCI_GPIO_MODE_OFFSET	9
519 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
520 
521 #define CP210X_ECI_GPIO_MODE_OFFSET	2
522 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
523 
524 #define CP210X_GPIO_MODE_OFFSET		8
525 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
526 
527 /* CP2105 port configuration values */
528 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
529 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
530 #define CP2105_GPIO1_RS485_MODE		BIT(2)
531 
532 /* CP2104 port configuration values */
533 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
534 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
535 #define CP2104_GPIO2_RS485_MODE		BIT(2)
536 
537 struct cp210x_quad_port_state {
538 	__le16 gpio_mode_pb0;
539 	__le16 gpio_mode_pb1;
540 	__le16 gpio_mode_pb2;
541 	__le16 gpio_mode_pb3;
542 	__le16 gpio_mode_pb4;
543 
544 	__le16 gpio_lowpower_pb0;
545 	__le16 gpio_lowpower_pb1;
546 	__le16 gpio_lowpower_pb2;
547 	__le16 gpio_lowpower_pb3;
548 	__le16 gpio_lowpower_pb4;
549 
550 	__le16 gpio_latch_pb0;
551 	__le16 gpio_latch_pb1;
552 	__le16 gpio_latch_pb2;
553 	__le16 gpio_latch_pb3;
554 	__le16 gpio_latch_pb4;
555 };
556 
557 /*
558  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0x49 bytes
559  * on a CP2108 chip.
560  *
561  * See https://www.silabs.com/documents/public/application-notes/an978-cp210x-usb-to-uart-api-specification.pdf
562  */
563 struct cp210x_quad_port_config {
564 	struct cp210x_quad_port_state reset_state;
565 	struct cp210x_quad_port_state suspend_state;
566 	u8 ipdelay_ifc[4];
567 	u8 enhancedfxn_ifc[4];
568 	u8 enhancedfxn_device;
569 	u8 extclkfreq[4];
570 } __packed;
571 
572 #define CP2108_EF_IFC_GPIO_TXLED		0x01
573 #define CP2108_EF_IFC_GPIO_RXLED		0x02
574 #define CP2108_EF_IFC_GPIO_RS485		0x04
575 #define CP2108_EF_IFC_GPIO_RS485_LOGIC		0x08
576 #define CP2108_EF_IFC_GPIO_CLOCK		0x10
577 #define CP2108_EF_IFC_DYNAMIC_SUSPEND		0x40
578 
579 /* CP2102N configuration array indices */
580 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
581 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
582 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
583 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
584 
585 /* CP2102N QFN20 port configuration values */
586 #define CP2102N_QFN20_GPIO2_TXLED_MODE		BIT(2)
587 #define CP2102N_QFN20_GPIO3_RXLED_MODE		BIT(3)
588 #define CP2102N_QFN20_GPIO1_RS485_MODE		BIT(4)
589 #define CP2102N_QFN20_GPIO0_CLK_MODE		BIT(6)
590 
591 /*
592  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x02 bytes
593  * for CP2102N, CP2103, CP2104 and CP2105.
594  */
595 struct cp210x_gpio_write {
596 	u8	mask;
597 	u8	state;
598 };
599 
600 /*
601  * CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x04 bytes
602  * for CP2108.
603  */
604 struct cp210x_gpio_write16 {
605 	__le16	mask;
606 	__le16	state;
607 };
608 
609 /*
610  * Helper to get interface number when we only have struct usb_serial.
611  */
612 static u8 cp210x_interface_num(struct usb_serial *serial)
613 {
614 	struct usb_host_interface *cur_altsetting;
615 
616 	cur_altsetting = serial->interface->cur_altsetting;
617 
618 	return cur_altsetting->desc.bInterfaceNumber;
619 }
620 
621 /*
622  * Reads a variable-sized block of CP210X_ registers, identified by req.
623  * Returns data into buf in native USB byte order.
624  */
625 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
626 		void *buf, int bufsize)
627 {
628 	struct usb_serial *serial = port->serial;
629 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
630 	void *dmabuf;
631 	int result;
632 
633 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
634 	if (!dmabuf)
635 		return -ENOMEM;
636 
637 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
638 			req, REQTYPE_INTERFACE_TO_HOST, 0,
639 			port_priv->bInterfaceNumber, dmabuf, bufsize,
640 			USB_CTRL_SET_TIMEOUT);
641 	if (result == bufsize) {
642 		memcpy(buf, dmabuf, bufsize);
643 		result = 0;
644 	} else {
645 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
646 				req, bufsize, result);
647 		if (result >= 0)
648 			result = -EIO;
649 	}
650 
651 	kfree(dmabuf);
652 
653 	return result;
654 }
655 
656 /*
657  * Reads any 8-bit CP210X_ register identified by req.
658  */
659 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
660 {
661 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
662 }
663 
664 /*
665  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
666  * Returns data into buf in native USB byte order.
667  */
668 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
669 				    void *buf, int bufsize)
670 {
671 	void *dmabuf;
672 	int result;
673 
674 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
675 	if (!dmabuf)
676 		return -ENOMEM;
677 
678 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
679 				 CP210X_VENDOR_SPECIFIC, type, val,
680 				 cp210x_interface_num(serial), dmabuf, bufsize,
681 				 USB_CTRL_GET_TIMEOUT);
682 	if (result == bufsize) {
683 		memcpy(buf, dmabuf, bufsize);
684 		result = 0;
685 	} else {
686 		dev_err(&serial->interface->dev,
687 			"failed to get vendor val 0x%04x size %d: %d\n", val,
688 			bufsize, result);
689 		if (result >= 0)
690 			result = -EIO;
691 	}
692 
693 	kfree(dmabuf);
694 
695 	return result;
696 }
697 
698 /*
699  * Writes any 16-bit CP210X_ register (req) whose value is passed
700  * entirely in the wValue field of the USB request.
701  */
702 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
703 {
704 	struct usb_serial *serial = port->serial;
705 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
706 	int result;
707 
708 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
709 			req, REQTYPE_HOST_TO_INTERFACE, val,
710 			port_priv->bInterfaceNumber, NULL, 0,
711 			USB_CTRL_SET_TIMEOUT);
712 	if (result < 0) {
713 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
714 				req, result);
715 	}
716 
717 	return result;
718 }
719 
720 /*
721  * Writes a variable-sized block of CP210X_ registers, identified by req.
722  * Data in buf must be in native USB byte order.
723  */
724 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
725 		void *buf, int bufsize)
726 {
727 	struct usb_serial *serial = port->serial;
728 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
729 	void *dmabuf;
730 	int result;
731 
732 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
733 	if (!dmabuf)
734 		return -ENOMEM;
735 
736 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
737 			req, REQTYPE_HOST_TO_INTERFACE, 0,
738 			port_priv->bInterfaceNumber, dmabuf, bufsize,
739 			USB_CTRL_SET_TIMEOUT);
740 
741 	kfree(dmabuf);
742 
743 	if (result < 0) {
744 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
745 				req, bufsize, result);
746 		return result;
747 	}
748 
749 	return 0;
750 }
751 
752 /*
753  * Writes any 32-bit CP210X_ register identified by req.
754  */
755 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
756 {
757 	__le32 le32_val;
758 
759 	le32_val = cpu_to_le32(val);
760 
761 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
762 }
763 
764 #ifdef CONFIG_GPIOLIB
765 /*
766  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
767  * Data in buf must be in native USB byte order.
768  */
769 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
770 				     u16 val, void *buf, int bufsize)
771 {
772 	void *dmabuf;
773 	int result;
774 
775 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
776 	if (!dmabuf)
777 		return -ENOMEM;
778 
779 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
780 				 CP210X_VENDOR_SPECIFIC, type, val,
781 				 cp210x_interface_num(serial), dmabuf, bufsize,
782 				 USB_CTRL_SET_TIMEOUT);
783 
784 	kfree(dmabuf);
785 
786 	if (result < 0) {
787 		dev_err(&serial->interface->dev,
788 			"failed to set vendor val 0x%04x size %d: %d\n", val,
789 			bufsize, result);
790 		return result;
791 	}
792 
793 	return 0;
794 }
795 #endif
796 
797 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
798 {
799 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
800 	int result;
801 
802 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
803 	if (result) {
804 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
805 		return result;
806 	}
807 
808 	if (tty)
809 		cp210x_set_termios(tty, port, NULL);
810 
811 	result = usb_serial_generic_open(tty, port);
812 	if (result)
813 		goto err_disable;
814 
815 	return 0;
816 
817 err_disable:
818 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
819 	port_priv->event_mode = false;
820 
821 	return result;
822 }
823 
824 static void cp210x_close(struct usb_serial_port *port)
825 {
826 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
827 
828 	usb_serial_generic_close(port);
829 
830 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
831 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
832 
833 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
834 
835 	/* Disabling the interface disables event-insertion mode. */
836 	port_priv->event_mode = false;
837 }
838 
839 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
840 {
841 	if (lsr & CP210X_LSR_BREAK) {
842 		port->icount.brk++;
843 		*flag = TTY_BREAK;
844 	} else if (lsr & CP210X_LSR_PARITY) {
845 		port->icount.parity++;
846 		*flag = TTY_PARITY;
847 	} else if (lsr & CP210X_LSR_FRAME) {
848 		port->icount.frame++;
849 		*flag = TTY_FRAME;
850 	}
851 
852 	if (lsr & CP210X_LSR_OVERRUN) {
853 		port->icount.overrun++;
854 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
855 	}
856 }
857 
858 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
859 {
860 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
861 
862 	switch (port_priv->event_state) {
863 	case ES_DATA:
864 		if (*ch == CP210X_ESCCHAR) {
865 			port_priv->event_state = ES_ESCAPE;
866 			break;
867 		}
868 		return false;
869 	case ES_ESCAPE:
870 		switch (*ch) {
871 		case 0:
872 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
873 			*ch = CP210X_ESCCHAR;
874 			port_priv->event_state = ES_DATA;
875 			return false;
876 		case 1:
877 			port_priv->event_state = ES_LSR_DATA_0;
878 			break;
879 		case 2:
880 			port_priv->event_state = ES_LSR;
881 			break;
882 		case 3:
883 			port_priv->event_state = ES_MSR;
884 			break;
885 		default:
886 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
887 			port_priv->event_state = ES_DATA;
888 			break;
889 		}
890 		break;
891 	case ES_LSR_DATA_0:
892 		port_priv->lsr = *ch;
893 		port_priv->event_state = ES_LSR_DATA_1;
894 		break;
895 	case ES_LSR_DATA_1:
896 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
897 				__func__, port_priv->lsr, *ch);
898 		cp210x_process_lsr(port, port_priv->lsr, flag);
899 		port_priv->event_state = ES_DATA;
900 		return false;
901 	case ES_LSR:
902 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
903 		port_priv->lsr = *ch;
904 		cp210x_process_lsr(port, port_priv->lsr, flag);
905 		port_priv->event_state = ES_DATA;
906 		break;
907 	case ES_MSR:
908 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
909 		/* unimplemented */
910 		port_priv->event_state = ES_DATA;
911 		break;
912 	}
913 
914 	return true;
915 }
916 
917 static void cp210x_process_read_urb(struct urb *urb)
918 {
919 	struct usb_serial_port *port = urb->context;
920 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
921 	unsigned char *ch = urb->transfer_buffer;
922 	char flag;
923 	int i;
924 
925 	if (!urb->actual_length)
926 		return;
927 
928 	if (port_priv->event_mode) {
929 		for (i = 0; i < urb->actual_length; i++, ch++) {
930 			flag = TTY_NORMAL;
931 
932 			if (cp210x_process_char(port, ch, &flag))
933 				continue;
934 
935 			tty_insert_flip_char(&port->port, *ch, flag);
936 		}
937 	} else {
938 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
939 	}
940 	tty_flip_buffer_push(&port->port);
941 }
942 
943 /*
944  * Read how many bytes are waiting in the TX queue.
945  */
946 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
947 		u32 *count)
948 {
949 	struct usb_serial *serial = port->serial;
950 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
951 	struct cp210x_comm_status *sts;
952 	int result;
953 
954 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
955 	if (!sts)
956 		return -ENOMEM;
957 
958 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
959 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
960 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
961 			USB_CTRL_GET_TIMEOUT);
962 	if (result == sizeof(*sts)) {
963 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
964 		result = 0;
965 	} else {
966 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
967 		if (result >= 0)
968 			result = -EIO;
969 	}
970 
971 	kfree(sts);
972 
973 	return result;
974 }
975 
976 static bool cp210x_tx_empty(struct usb_serial_port *port)
977 {
978 	int err;
979 	u32 count;
980 
981 	err = cp210x_get_tx_queue_byte_count(port, &count);
982 	if (err)
983 		return true;
984 
985 	return !count;
986 }
987 
988 struct cp210x_rate {
989 	speed_t rate;
990 	speed_t high;
991 };
992 
993 static const struct cp210x_rate cp210x_an205_table1[] = {
994 	{ 300, 300 },
995 	{ 600, 600 },
996 	{ 1200, 1200 },
997 	{ 1800, 1800 },
998 	{ 2400, 2400 },
999 	{ 4000, 4000 },
1000 	{ 4800, 4803 },
1001 	{ 7200, 7207 },
1002 	{ 9600, 9612 },
1003 	{ 14400, 14428 },
1004 	{ 16000, 16062 },
1005 	{ 19200, 19250 },
1006 	{ 28800, 28912 },
1007 	{ 38400, 38601 },
1008 	{ 51200, 51558 },
1009 	{ 56000, 56280 },
1010 	{ 57600, 58053 },
1011 	{ 64000, 64111 },
1012 	{ 76800, 77608 },
1013 	{ 115200, 117028 },
1014 	{ 128000, 129347 },
1015 	{ 153600, 156868 },
1016 	{ 230400, 237832 },
1017 	{ 250000, 254234 },
1018 	{ 256000, 273066 },
1019 	{ 460800, 491520 },
1020 	{ 500000, 567138 },
1021 	{ 576000, 670254 },
1022 	{ 921600, UINT_MAX }
1023 };
1024 
1025 /*
1026  * Quantises the baud rate as per AN205 Table 1
1027  */
1028 static speed_t cp210x_get_an205_rate(speed_t baud)
1029 {
1030 	int i;
1031 
1032 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1033 		if (baud <= cp210x_an205_table1[i].high)
1034 			break;
1035 	}
1036 
1037 	return cp210x_an205_table1[i].rate;
1038 }
1039 
1040 static speed_t cp210x_get_actual_rate(speed_t baud)
1041 {
1042 	unsigned int prescale = 1;
1043 	unsigned int div;
1044 
1045 	if (baud <= 365)
1046 		prescale = 4;
1047 
1048 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1049 	baud = 48000000 / (2 * prescale * div);
1050 
1051 	return baud;
1052 }
1053 
1054 /*
1055  * CP2101 supports the following baud rates:
1056  *
1057  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1058  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1059  *
1060  * CP2102 and CP2103 support the following additional rates:
1061  *
1062  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1063  *	576000
1064  *
1065  * The device will map a requested rate to a supported one, but the result
1066  * of requests for rates greater than 1053257 is undefined (see AN205).
1067  *
1068  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1069  * respectively, with an error less than 1%. The actual rates are determined
1070  * by
1071  *
1072  *	div = round(freq / (2 x prescale x request))
1073  *	actual = freq / (2 x prescale x div)
1074  *
1075  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1076  * or 1 otherwise.
1077  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1078  * otherwise.
1079  */
1080 static void cp210x_change_speed(struct tty_struct *tty,
1081 		struct usb_serial_port *port, struct ktermios *old_termios)
1082 {
1083 	struct usb_serial *serial = port->serial;
1084 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1085 	u32 baud;
1086 
1087 	/*
1088 	 * This maps the requested rate to the actual rate, a valid rate on
1089 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1090 	 *
1091 	 * NOTE: B0 is not implemented.
1092 	 */
1093 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1094 
1095 	if (priv->use_actual_rate)
1096 		baud = cp210x_get_actual_rate(baud);
1097 	else if (baud < 1000000)
1098 		baud = cp210x_get_an205_rate(baud);
1099 
1100 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1101 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1102 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1103 		if (old_termios)
1104 			baud = old_termios->c_ospeed;
1105 		else
1106 			baud = 9600;
1107 	}
1108 
1109 	tty_encode_baud_rate(tty, baud, baud);
1110 }
1111 
1112 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1113 {
1114 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1115 	int ret;
1116 
1117 	if (port_priv->event_mode)
1118 		return;
1119 
1120 	port_priv->event_state = ES_DATA;
1121 	port_priv->event_mode = true;
1122 
1123 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1124 	if (ret) {
1125 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1126 		port_priv->event_mode = false;
1127 	}
1128 }
1129 
1130 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1131 {
1132 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1133 	int ret;
1134 
1135 	if (!port_priv->event_mode)
1136 		return;
1137 
1138 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1139 	if (ret) {
1140 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1141 		return;
1142 	}
1143 
1144 	port_priv->event_mode = false;
1145 }
1146 
1147 static int cp210x_set_chars(struct usb_serial_port *port,
1148 		struct cp210x_special_chars *chars)
1149 {
1150 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1151 	struct usb_serial *serial = port->serial;
1152 	void *dmabuf;
1153 	int result;
1154 
1155 	dmabuf = kmemdup(chars, sizeof(*chars), GFP_KERNEL);
1156 	if (!dmabuf)
1157 		return -ENOMEM;
1158 
1159 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1160 				CP210X_SET_CHARS, REQTYPE_HOST_TO_INTERFACE, 0,
1161 				port_priv->bInterfaceNumber,
1162 				dmabuf, sizeof(*chars), USB_CTRL_SET_TIMEOUT);
1163 
1164 	kfree(dmabuf);
1165 
1166 	if (result < 0) {
1167 		dev_err(&port->dev, "failed to set special chars: %d\n", result);
1168 		return result;
1169 	}
1170 
1171 	return 0;
1172 }
1173 
1174 static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b)
1175 {
1176 	bool iflag_change, cc_change;
1177 
1178 	iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF));
1179 	cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] ||
1180 			a->c_cc[VSTOP] != b->c_cc[VSTOP];
1181 
1182 	return tty_termios_hw_change(a, b) || iflag_change || cc_change;
1183 }
1184 
1185 static void cp210x_set_flow_control(struct tty_struct *tty,
1186 		struct usb_serial_port *port, struct ktermios *old_termios)
1187 {
1188 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1189 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1190 	struct cp210x_special_chars chars;
1191 	struct cp210x_flow_ctl flow_ctl;
1192 	u32 flow_repl;
1193 	u32 ctl_hs;
1194 	int ret;
1195 
1196 	/*
1197 	 * Some CP2102N interpret ulXonLimit as ulFlowReplace (erratum
1198 	 * CP2102N_E104). Report back that flow control is not supported.
1199 	 */
1200 	if (priv->no_flow_control) {
1201 		tty->termios.c_cflag &= ~CRTSCTS;
1202 		tty->termios.c_iflag &= ~(IXON | IXOFF);
1203 	}
1204 
1205 	if (old_termios &&
1206 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
1207 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
1208 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
1209 			START_CHAR(tty) == old_termios->c_cc[VSTART] &&
1210 			STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) {
1211 		return;
1212 	}
1213 
1214 	if (I_IXON(tty) || I_IXOFF(tty)) {
1215 		memset(&chars, 0, sizeof(chars));
1216 
1217 		chars.bXonChar = START_CHAR(tty);
1218 		chars.bXoffChar = STOP_CHAR(tty);
1219 
1220 		ret = cp210x_set_chars(port, &chars);
1221 		if (ret)
1222 			return;
1223 	}
1224 
1225 	mutex_lock(&port_priv->mutex);
1226 
1227 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1228 			sizeof(flow_ctl));
1229 	if (ret)
1230 		goto out_unlock;
1231 
1232 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1233 	flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1234 
1235 	ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1236 	ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1237 	ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1238 	ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1239 	if (port_priv->dtr)
1240 		ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1241 	else
1242 		ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1243 
1244 	flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1245 	if (C_CRTSCTS(tty)) {
1246 		ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1247 		if (port_priv->rts)
1248 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1249 		else
1250 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1251 		port_priv->crtscts = true;
1252 	} else {
1253 		ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1254 		if (port_priv->rts)
1255 			flow_repl |= CP210X_SERIAL_RTS_ACTIVE;
1256 		else
1257 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1258 		port_priv->crtscts = false;
1259 	}
1260 
1261 	if (I_IXOFF(tty)) {
1262 		flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
1263 
1264 		flow_ctl.ulXonLimit = cpu_to_le32(128);
1265 		flow_ctl.ulXoffLimit = cpu_to_le32(128);
1266 	} else {
1267 		flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
1268 	}
1269 
1270 	if (I_IXON(tty))
1271 		flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
1272 	else
1273 		flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
1274 
1275 	dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n", __func__,
1276 			ctl_hs, flow_repl);
1277 
1278 	flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1279 	flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1280 
1281 	cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1282 			sizeof(flow_ctl));
1283 out_unlock:
1284 	mutex_unlock(&port_priv->mutex);
1285 }
1286 
1287 static void cp210x_set_termios(struct tty_struct *tty,
1288 		struct usb_serial_port *port, struct ktermios *old_termios)
1289 {
1290 	struct cp210x_serial_private *priv = usb_get_serial_data(port->serial);
1291 	u16 bits;
1292 	int ret;
1293 
1294 	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
1295 		return;
1296 
1297 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)
1298 		cp210x_change_speed(tty, port, old_termios);
1299 
1300 	/* CP2101 only supports CS8, 1 stop bit and non-stick parity. */
1301 	if (priv->partnum == CP210X_PARTNUM_CP2101) {
1302 		tty->termios.c_cflag &= ~(CSIZE | CSTOPB | CMSPAR);
1303 		tty->termios.c_cflag |= CS8;
1304 	}
1305 
1306 	bits = 0;
1307 
1308 	switch (C_CSIZE(tty)) {
1309 	case CS5:
1310 		bits |= BITS_DATA_5;
1311 		break;
1312 	case CS6:
1313 		bits |= BITS_DATA_6;
1314 		break;
1315 	case CS7:
1316 		bits |= BITS_DATA_7;
1317 		break;
1318 	case CS8:
1319 	default:
1320 		bits |= BITS_DATA_8;
1321 		break;
1322 	}
1323 
1324 	if (C_PARENB(tty)) {
1325 		if (C_CMSPAR(tty)) {
1326 			if (C_PARODD(tty))
1327 				bits |= BITS_PARITY_MARK;
1328 			else
1329 				bits |= BITS_PARITY_SPACE;
1330 		} else {
1331 			if (C_PARODD(tty))
1332 				bits |= BITS_PARITY_ODD;
1333 			else
1334 				bits |= BITS_PARITY_EVEN;
1335 		}
1336 	}
1337 
1338 	if (C_CSTOPB(tty))
1339 		bits |= BITS_STOP_2;
1340 	else
1341 		bits |= BITS_STOP_1;
1342 
1343 	ret = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1344 	if (ret)
1345 		dev_err(&port->dev, "failed to set line control: %d\n", ret);
1346 
1347 	cp210x_set_flow_control(tty, port, old_termios);
1348 
1349 	/*
1350 	 * Enable event-insertion mode only if input parity checking is
1351 	 * enabled for now.
1352 	 */
1353 	if (I_INPCK(tty))
1354 		cp210x_enable_event_mode(port);
1355 	else
1356 		cp210x_disable_event_mode(port);
1357 }
1358 
1359 static int cp210x_tiocmset(struct tty_struct *tty,
1360 		unsigned int set, unsigned int clear)
1361 {
1362 	struct usb_serial_port *port = tty->driver_data;
1363 	return cp210x_tiocmset_port(port, set, clear);
1364 }
1365 
1366 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1367 		unsigned int set, unsigned int clear)
1368 {
1369 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1370 	struct cp210x_flow_ctl flow_ctl;
1371 	u32 ctl_hs, flow_repl;
1372 	u16 control = 0;
1373 	int ret;
1374 
1375 	mutex_lock(&port_priv->mutex);
1376 
1377 	if (set & TIOCM_RTS) {
1378 		port_priv->rts = true;
1379 		control |= CONTROL_RTS;
1380 		control |= CONTROL_WRITE_RTS;
1381 	}
1382 	if (set & TIOCM_DTR) {
1383 		port_priv->dtr = true;
1384 		control |= CONTROL_DTR;
1385 		control |= CONTROL_WRITE_DTR;
1386 	}
1387 	if (clear & TIOCM_RTS) {
1388 		port_priv->rts = false;
1389 		control &= ~CONTROL_RTS;
1390 		control |= CONTROL_WRITE_RTS;
1391 	}
1392 	if (clear & TIOCM_DTR) {
1393 		port_priv->dtr = false;
1394 		control &= ~CONTROL_DTR;
1395 		control |= CONTROL_WRITE_DTR;
1396 	}
1397 
1398 	/*
1399 	 * Use SET_FLOW to set DTR and enable/disable auto-RTS when hardware
1400 	 * flow control is enabled.
1401 	 */
1402 	if (port_priv->crtscts && control & CONTROL_WRITE_RTS) {
1403 		ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1404 				sizeof(flow_ctl));
1405 		if (ret)
1406 			goto out_unlock;
1407 
1408 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1409 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1410 
1411 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1412 		if (port_priv->dtr)
1413 			ctl_hs |= CP210X_SERIAL_DTR_ACTIVE;
1414 		else
1415 			ctl_hs |= CP210X_SERIAL_DTR_INACTIVE;
1416 
1417 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1418 		if (port_priv->rts)
1419 			flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL;
1420 		else
1421 			flow_repl |= CP210X_SERIAL_RTS_INACTIVE;
1422 
1423 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1424 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1425 
1426 		dev_dbg(&port->dev, "%s - ctrl = 0x%02x, flow = 0x%02x\n",
1427 				__func__, ctl_hs, flow_repl);
1428 
1429 		ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1430 				sizeof(flow_ctl));
1431 	} else {
1432 		dev_dbg(&port->dev, "%s - control = 0x%04x\n", __func__, control);
1433 
1434 		ret = cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1435 	}
1436 out_unlock:
1437 	mutex_unlock(&port_priv->mutex);
1438 
1439 	return ret;
1440 }
1441 
1442 static void cp210x_dtr_rts(struct usb_serial_port *port, int on)
1443 {
1444 	if (on)
1445 		cp210x_tiocmset_port(port, TIOCM_DTR | TIOCM_RTS, 0);
1446 	else
1447 		cp210x_tiocmset_port(port, 0, TIOCM_DTR | TIOCM_RTS);
1448 }
1449 
1450 static int cp210x_tiocmget(struct tty_struct *tty)
1451 {
1452 	struct usb_serial_port *port = tty->driver_data;
1453 	u8 control;
1454 	int result;
1455 
1456 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1457 	if (result)
1458 		return result;
1459 
1460 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1461 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1462 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1463 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1464 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1465 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1466 
1467 	dev_dbg(&port->dev, "%s - control = 0x%02x\n", __func__, control);
1468 
1469 	return result;
1470 }
1471 
1472 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1473 {
1474 	struct usb_serial_port *port = tty->driver_data;
1475 	u16 state;
1476 
1477 	if (break_state == 0)
1478 		state = BREAK_OFF;
1479 	else
1480 		state = BREAK_ON;
1481 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1482 		state == BREAK_OFF ? "off" : "on");
1483 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1484 }
1485 
1486 #ifdef CONFIG_GPIOLIB
1487 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1488 {
1489 	struct usb_serial *serial = gpiochip_get_data(gc);
1490 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1491 	u8 req_type;
1492 	u16 mask;
1493 	int result;
1494 	int len;
1495 
1496 	result = usb_autopm_get_interface(serial->interface);
1497 	if (result)
1498 		return result;
1499 
1500 	switch (priv->partnum) {
1501 	case CP210X_PARTNUM_CP2105:
1502 		req_type = REQTYPE_INTERFACE_TO_HOST;
1503 		len = 1;
1504 		break;
1505 	case CP210X_PARTNUM_CP2108:
1506 		req_type = REQTYPE_INTERFACE_TO_HOST;
1507 		len = 2;
1508 		break;
1509 	default:
1510 		req_type = REQTYPE_DEVICE_TO_HOST;
1511 		len = 1;
1512 		break;
1513 	}
1514 
1515 	mask = 0;
1516 	result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH,
1517 					  &mask, len);
1518 
1519 	usb_autopm_put_interface(serial->interface);
1520 
1521 	if (result < 0)
1522 		return result;
1523 
1524 	le16_to_cpus(&mask);
1525 
1526 	return !!(mask & BIT(gpio));
1527 }
1528 
1529 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1530 {
1531 	struct usb_serial *serial = gpiochip_get_data(gc);
1532 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1533 	struct cp210x_gpio_write16 buf16;
1534 	struct cp210x_gpio_write buf;
1535 	u16 mask, state;
1536 	u16 wIndex;
1537 	int result;
1538 
1539 	if (value == 1)
1540 		state = BIT(gpio);
1541 	else
1542 		state = 0;
1543 
1544 	mask = BIT(gpio);
1545 
1546 	result = usb_autopm_get_interface(serial->interface);
1547 	if (result)
1548 		goto out;
1549 
1550 	switch (priv->partnum) {
1551 	case CP210X_PARTNUM_CP2105:
1552 		buf.mask = (u8)mask;
1553 		buf.state = (u8)state;
1554 		result = cp210x_write_vendor_block(serial,
1555 						   REQTYPE_HOST_TO_INTERFACE,
1556 						   CP210X_WRITE_LATCH, &buf,
1557 						   sizeof(buf));
1558 		break;
1559 	case CP210X_PARTNUM_CP2108:
1560 		buf16.mask = cpu_to_le16(mask);
1561 		buf16.state = cpu_to_le16(state);
1562 		result = cp210x_write_vendor_block(serial,
1563 						   REQTYPE_HOST_TO_INTERFACE,
1564 						   CP210X_WRITE_LATCH, &buf16,
1565 						   sizeof(buf16));
1566 		break;
1567 	default:
1568 		wIndex = state << 8 | mask;
1569 		result = usb_control_msg(serial->dev,
1570 					 usb_sndctrlpipe(serial->dev, 0),
1571 					 CP210X_VENDOR_SPECIFIC,
1572 					 REQTYPE_HOST_TO_DEVICE,
1573 					 CP210X_WRITE_LATCH,
1574 					 wIndex,
1575 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1576 		break;
1577 	}
1578 
1579 	usb_autopm_put_interface(serial->interface);
1580 out:
1581 	if (result < 0) {
1582 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1583 				result);
1584 	}
1585 }
1586 
1587 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1588 {
1589 	struct usb_serial *serial = gpiochip_get_data(gc);
1590 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1591 
1592 	return priv->gpio_input & BIT(gpio);
1593 }
1594 
1595 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1596 {
1597 	struct usb_serial *serial = gpiochip_get_data(gc);
1598 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1599 
1600 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1601 		/* hardware does not support an input mode */
1602 		return -ENOTSUPP;
1603 	}
1604 
1605 	/* push-pull pins cannot be changed to be inputs */
1606 	if (priv->gpio_pushpull & BIT(gpio))
1607 		return -EINVAL;
1608 
1609 	/* make sure to release pin if it is being driven low */
1610 	cp210x_gpio_set(gc, gpio, 1);
1611 
1612 	priv->gpio_input |= BIT(gpio);
1613 
1614 	return 0;
1615 }
1616 
1617 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1618 					int value)
1619 {
1620 	struct usb_serial *serial = gpiochip_get_data(gc);
1621 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1622 
1623 	priv->gpio_input &= ~BIT(gpio);
1624 	cp210x_gpio_set(gc, gpio, value);
1625 
1626 	return 0;
1627 }
1628 
1629 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1630 				  unsigned long config)
1631 {
1632 	struct usb_serial *serial = gpiochip_get_data(gc);
1633 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1634 	enum pin_config_param param = pinconf_to_config_param(config);
1635 
1636 	/* Succeed only if in correct mode (this can't be set at runtime) */
1637 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1638 	    (priv->gpio_pushpull & BIT(gpio)))
1639 		return 0;
1640 
1641 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1642 	    !(priv->gpio_pushpull & BIT(gpio)))
1643 		return 0;
1644 
1645 	return -ENOTSUPP;
1646 }
1647 
1648 static int cp210x_gpio_init_valid_mask(struct gpio_chip *gc,
1649 		unsigned long *valid_mask, unsigned int ngpios)
1650 {
1651 	struct usb_serial *serial = gpiochip_get_data(gc);
1652 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1653 	struct device *dev = &serial->interface->dev;
1654 	unsigned long altfunc_mask = priv->gpio_altfunc;
1655 
1656 	bitmap_complement(valid_mask, &altfunc_mask, ngpios);
1657 
1658 	if (bitmap_empty(valid_mask, ngpios))
1659 		dev_dbg(dev, "no pin configured for GPIO\n");
1660 	else
1661 		dev_dbg(dev, "GPIO.%*pbl configured for GPIO\n", ngpios,
1662 				valid_mask);
1663 	return 0;
1664 }
1665 
1666 /*
1667  * This function is for configuring GPIO using shared pins, where other signals
1668  * are made unavailable by configuring the use of GPIO. This is believed to be
1669  * only applicable to the cp2105 at this point, the other devices supported by
1670  * this driver that provide GPIO do so in a way that does not impact other
1671  * signals and are thus expected to have very different initialisation.
1672  */
1673 static int cp2105_gpioconf_init(struct usb_serial *serial)
1674 {
1675 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1676 	struct cp210x_pin_mode mode;
1677 	struct cp210x_dual_port_config config;
1678 	u8 intf_num = cp210x_interface_num(serial);
1679 	u8 iface_config;
1680 	int result;
1681 
1682 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1683 					  CP210X_GET_DEVICEMODE, &mode,
1684 					  sizeof(mode));
1685 	if (result < 0)
1686 		return result;
1687 
1688 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1689 					  CP210X_GET_PORTCONFIG, &config,
1690 					  sizeof(config));
1691 	if (result < 0)
1692 		return result;
1693 
1694 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1695 	if (intf_num == 0) {
1696 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1697 			/* mark all GPIOs of this interface as reserved */
1698 			priv->gpio_altfunc = 0xff;
1699 			return 0;
1700 		}
1701 
1702 		iface_config = config.eci_cfg;
1703 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1704 						CP210X_ECI_GPIO_MODE_MASK) >>
1705 						CP210X_ECI_GPIO_MODE_OFFSET);
1706 		priv->gc.ngpio = 2;
1707 	} else if (intf_num == 1) {
1708 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1709 			/* mark all GPIOs of this interface as reserved */
1710 			priv->gpio_altfunc = 0xff;
1711 			return 0;
1712 		}
1713 
1714 		iface_config = config.sci_cfg;
1715 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1716 						CP210X_SCI_GPIO_MODE_MASK) >>
1717 						CP210X_SCI_GPIO_MODE_OFFSET);
1718 		priv->gc.ngpio = 3;
1719 	} else {
1720 		return -ENODEV;
1721 	}
1722 
1723 	/* mark all pins which are not in GPIO mode */
1724 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1725 		priv->gpio_altfunc |= BIT(0);
1726 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1727 			CP2105_GPIO1_RS485_MODE))
1728 		priv->gpio_altfunc |= BIT(1);
1729 
1730 	/* driver implementation for CP2105 only supports outputs */
1731 	priv->gpio_input = 0;
1732 
1733 	return 0;
1734 }
1735 
1736 static int cp2104_gpioconf_init(struct usb_serial *serial)
1737 {
1738 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1739 	struct cp210x_single_port_config config;
1740 	u8 iface_config;
1741 	u8 gpio_latch;
1742 	int result;
1743 	u8 i;
1744 
1745 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1746 					  CP210X_GET_PORTCONFIG, &config,
1747 					  sizeof(config));
1748 	if (result < 0)
1749 		return result;
1750 
1751 	priv->gc.ngpio = 4;
1752 
1753 	iface_config = config.device_cfg;
1754 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1755 					CP210X_GPIO_MODE_MASK) >>
1756 					CP210X_GPIO_MODE_OFFSET);
1757 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1758 					CP210X_GPIO_MODE_MASK) >>
1759 					CP210X_GPIO_MODE_OFFSET);
1760 
1761 	/* mark all pins which are not in GPIO mode */
1762 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1763 		priv->gpio_altfunc |= BIT(0);
1764 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1765 		priv->gpio_altfunc |= BIT(1);
1766 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1767 		priv->gpio_altfunc |= BIT(2);
1768 
1769 	/*
1770 	 * Like CP2102N, CP2104 has also no strict input and output pin
1771 	 * modes.
1772 	 * Do the same input mode emulation as CP2102N.
1773 	 */
1774 	for (i = 0; i < priv->gc.ngpio; ++i) {
1775 		/*
1776 		 * Set direction to "input" iff pin is open-drain and reset
1777 		 * value is 1.
1778 		 */
1779 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1780 			priv->gpio_input |= BIT(i);
1781 	}
1782 
1783 	return 0;
1784 }
1785 
1786 static int cp2108_gpio_init(struct usb_serial *serial)
1787 {
1788 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1789 	struct cp210x_quad_port_config config;
1790 	u16 gpio_latch;
1791 	int result;
1792 	u8 i;
1793 
1794 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1795 					  CP210X_GET_PORTCONFIG, &config,
1796 					  sizeof(config));
1797 	if (result < 0)
1798 		return result;
1799 
1800 	priv->gc.ngpio = 16;
1801 	priv->gpio_pushpull = le16_to_cpu(config.reset_state.gpio_mode_pb1);
1802 	gpio_latch = le16_to_cpu(config.reset_state.gpio_latch_pb1);
1803 
1804 	/*
1805 	 * Mark all pins which are not in GPIO mode.
1806 	 *
1807 	 * Refer to table 9.1 "GPIO Mode alternate Functions" in the datasheet:
1808 	 * https://www.silabs.com/documents/public/data-sheets/cp2108-datasheet.pdf
1809 	 *
1810 	 * Alternate functions of GPIO0 to GPIO3 are determine by enhancedfxn_ifc[0]
1811 	 * and the similarly for the other pins; enhancedfxn_ifc[1]: GPIO4 to GPIO7,
1812 	 * enhancedfxn_ifc[2]: GPIO8 to GPIO11, enhancedfxn_ifc[3]: GPIO12 to GPIO15.
1813 	 */
1814 	for (i = 0; i < 4; i++) {
1815 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_TXLED)
1816 			priv->gpio_altfunc |= BIT(i * 4);
1817 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RXLED)
1818 			priv->gpio_altfunc |= BIT((i * 4) + 1);
1819 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_RS485)
1820 			priv->gpio_altfunc |= BIT((i * 4) + 2);
1821 		if (config.enhancedfxn_ifc[i] & CP2108_EF_IFC_GPIO_CLOCK)
1822 			priv->gpio_altfunc |= BIT((i * 4) + 3);
1823 	}
1824 
1825 	/*
1826 	 * Like CP2102N, CP2108 has also no strict input and output pin
1827 	 * modes. Do the same input mode emulation as CP2102N.
1828 	 */
1829 	for (i = 0; i < priv->gc.ngpio; ++i) {
1830 		/*
1831 		 * Set direction to "input" iff pin is open-drain and reset
1832 		 * value is 1.
1833 		 */
1834 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1835 			priv->gpio_input |= BIT(i);
1836 	}
1837 
1838 	return 0;
1839 }
1840 
1841 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1842 {
1843 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1844 	const u16 config_size = 0x02a6;
1845 	u8 gpio_rst_latch;
1846 	u8 config_version;
1847 	u8 gpio_pushpull;
1848 	u8 *config_buf;
1849 	u8 gpio_latch;
1850 	u8 gpio_ctrl;
1851 	int result;
1852 	u8 i;
1853 
1854 	/*
1855 	 * Retrieve device configuration from the device.
1856 	 * The array received contains all customization settings done at the
1857 	 * factory/manufacturer. Format of the array is documented at the
1858 	 * time of writing at:
1859 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1860 	 */
1861 	config_buf = kmalloc(config_size, GFP_KERNEL);
1862 	if (!config_buf)
1863 		return -ENOMEM;
1864 
1865 	result = cp210x_read_vendor_block(serial,
1866 					  REQTYPE_DEVICE_TO_HOST,
1867 					  CP210X_READ_2NCONFIG,
1868 					  config_buf,
1869 					  config_size);
1870 	if (result < 0) {
1871 		kfree(config_buf);
1872 		return result;
1873 	}
1874 
1875 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1876 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1877 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1878 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1879 
1880 	kfree(config_buf);
1881 
1882 	/* Make sure this is a config format we understand. */
1883 	if (config_version != 0x01)
1884 		return -ENOTSUPP;
1885 
1886 	priv->gc.ngpio = 4;
1887 
1888 	/*
1889 	 * Get default pin states after reset. Needed so we can determine
1890 	 * the direction of an open-drain pin.
1891 	 */
1892 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1893 
1894 	/* 0 indicates open-drain mode, 1 is push-pull */
1895 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1896 
1897 	/* 0 indicates GPIO mode, 1 is alternate function */
1898 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN20) {
1899 		/* QFN20 is special... */
1900 		if (gpio_ctrl & CP2102N_QFN20_GPIO0_CLK_MODE)   /* GPIO 0 */
1901 			priv->gpio_altfunc |= BIT(0);
1902 		if (gpio_ctrl & CP2102N_QFN20_GPIO1_RS485_MODE) /* GPIO 1 */
1903 			priv->gpio_altfunc |= BIT(1);
1904 		if (gpio_ctrl & CP2102N_QFN20_GPIO2_TXLED_MODE) /* GPIO 2 */
1905 			priv->gpio_altfunc |= BIT(2);
1906 		if (gpio_ctrl & CP2102N_QFN20_GPIO3_RXLED_MODE) /* GPIO 3 */
1907 			priv->gpio_altfunc |= BIT(3);
1908 	} else {
1909 		priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1910 	}
1911 
1912 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1913 		/*
1914 		 * For the QFN28 package, GPIO4-6 are controlled by
1915 		 * the low three bits of the mode/latch fields.
1916 		 * Contrary to the document linked above, the bits for
1917 		 * the SUSPEND pins are elsewhere.  No alternate
1918 		 * function is available for these pins.
1919 		 */
1920 		priv->gc.ngpio = 7;
1921 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1922 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1923 	}
1924 
1925 	/*
1926 	 * The CP2102N does not strictly has input and output pin modes,
1927 	 * it only knows open-drain and push-pull modes which is set at
1928 	 * factory. An open-drain pin can function both as an
1929 	 * input or an output. We emulate input mode for open-drain pins
1930 	 * by making sure they are not driven low, and we do not allow
1931 	 * push-pull pins to be set as an input.
1932 	 */
1933 	for (i = 0; i < priv->gc.ngpio; ++i) {
1934 		/*
1935 		 * Set direction to "input" iff pin is open-drain and reset
1936 		 * value is 1.
1937 		 */
1938 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1939 			priv->gpio_input |= BIT(i);
1940 	}
1941 
1942 	return 0;
1943 }
1944 
1945 static int cp210x_gpio_init(struct usb_serial *serial)
1946 {
1947 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1948 	int result;
1949 
1950 	switch (priv->partnum) {
1951 	case CP210X_PARTNUM_CP2104:
1952 		result = cp2104_gpioconf_init(serial);
1953 		break;
1954 	case CP210X_PARTNUM_CP2105:
1955 		result = cp2105_gpioconf_init(serial);
1956 		break;
1957 	case CP210X_PARTNUM_CP2108:
1958 		/*
1959 		 * The GPIOs are not tied to any specific port so only register
1960 		 * once for interface 0.
1961 		 */
1962 		if (cp210x_interface_num(serial) != 0)
1963 			return 0;
1964 		result = cp2108_gpio_init(serial);
1965 		break;
1966 	case CP210X_PARTNUM_CP2102N_QFN28:
1967 	case CP210X_PARTNUM_CP2102N_QFN24:
1968 	case CP210X_PARTNUM_CP2102N_QFN20:
1969 		result = cp2102n_gpioconf_init(serial);
1970 		break;
1971 	default:
1972 		return 0;
1973 	}
1974 
1975 	if (result < 0)
1976 		return result;
1977 
1978 	priv->gc.label = "cp210x";
1979 	priv->gc.get_direction = cp210x_gpio_direction_get;
1980 	priv->gc.direction_input = cp210x_gpio_direction_input;
1981 	priv->gc.direction_output = cp210x_gpio_direction_output;
1982 	priv->gc.get = cp210x_gpio_get;
1983 	priv->gc.set = cp210x_gpio_set;
1984 	priv->gc.set_config = cp210x_gpio_set_config;
1985 	priv->gc.init_valid_mask = cp210x_gpio_init_valid_mask;
1986 	priv->gc.owner = THIS_MODULE;
1987 	priv->gc.parent = &serial->interface->dev;
1988 	priv->gc.base = -1;
1989 	priv->gc.can_sleep = true;
1990 
1991 	result = gpiochip_add_data(&priv->gc, serial);
1992 	if (!result)
1993 		priv->gpio_registered = true;
1994 
1995 	return result;
1996 }
1997 
1998 static void cp210x_gpio_remove(struct usb_serial *serial)
1999 {
2000 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2001 
2002 	if (priv->gpio_registered) {
2003 		gpiochip_remove(&priv->gc);
2004 		priv->gpio_registered = false;
2005 	}
2006 }
2007 
2008 #else
2009 
2010 static int cp210x_gpio_init(struct usb_serial *serial)
2011 {
2012 	return 0;
2013 }
2014 
2015 static void cp210x_gpio_remove(struct usb_serial *serial)
2016 {
2017 	/* Nothing to do */
2018 }
2019 
2020 #endif
2021 
2022 static int cp210x_port_probe(struct usb_serial_port *port)
2023 {
2024 	struct usb_serial *serial = port->serial;
2025 	struct cp210x_port_private *port_priv;
2026 
2027 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
2028 	if (!port_priv)
2029 		return -ENOMEM;
2030 
2031 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
2032 	mutex_init(&port_priv->mutex);
2033 
2034 	usb_set_serial_port_data(port, port_priv);
2035 
2036 	return 0;
2037 }
2038 
2039 static void cp210x_port_remove(struct usb_serial_port *port)
2040 {
2041 	struct cp210x_port_private *port_priv;
2042 
2043 	port_priv = usb_get_serial_port_data(port);
2044 	kfree(port_priv);
2045 }
2046 
2047 static void cp210x_init_max_speed(struct usb_serial *serial)
2048 {
2049 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2050 	bool use_actual_rate = false;
2051 	speed_t min = 300;
2052 	speed_t max;
2053 
2054 	switch (priv->partnum) {
2055 	case CP210X_PARTNUM_CP2101:
2056 		max = 921600;
2057 		break;
2058 	case CP210X_PARTNUM_CP2102:
2059 	case CP210X_PARTNUM_CP2103:
2060 		max = 1000000;
2061 		break;
2062 	case CP210X_PARTNUM_CP2104:
2063 		use_actual_rate = true;
2064 		max = 2000000;
2065 		break;
2066 	case CP210X_PARTNUM_CP2108:
2067 		max = 2000000;
2068 		break;
2069 	case CP210X_PARTNUM_CP2105:
2070 		if (cp210x_interface_num(serial) == 0) {
2071 			use_actual_rate = true;
2072 			max = 2000000;	/* ECI */
2073 		} else {
2074 			min = 2400;
2075 			max = 921600;	/* SCI */
2076 		}
2077 		break;
2078 	case CP210X_PARTNUM_CP2102N_QFN28:
2079 	case CP210X_PARTNUM_CP2102N_QFN24:
2080 	case CP210X_PARTNUM_CP2102N_QFN20:
2081 		use_actual_rate = true;
2082 		max = 3000000;
2083 		break;
2084 	default:
2085 		max = 2000000;
2086 		break;
2087 	}
2088 
2089 	priv->min_speed = min;
2090 	priv->max_speed = max;
2091 	priv->use_actual_rate = use_actual_rate;
2092 }
2093 
2094 static int cp210x_get_fw_version(struct usb_serial *serial, u16 value)
2095 {
2096 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2097 	u8 ver[3];
2098 	int ret;
2099 
2100 	ret = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST, value,
2101 			ver, sizeof(ver));
2102 	if (ret)
2103 		return ret;
2104 
2105 	dev_dbg(&serial->interface->dev, "%s - %d.%d.%d\n", __func__,
2106 			ver[0], ver[1], ver[2]);
2107 
2108 	priv->fw_version = ver[0] << 16 | ver[1] << 8 | ver[2];
2109 
2110 	return 0;
2111 }
2112 
2113 static void cp210x_determine_quirks(struct usb_serial *serial)
2114 {
2115 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2116 	int ret;
2117 
2118 	switch (priv->partnum) {
2119 	case CP210X_PARTNUM_CP2102N_QFN28:
2120 	case CP210X_PARTNUM_CP2102N_QFN24:
2121 	case CP210X_PARTNUM_CP2102N_QFN20:
2122 		ret = cp210x_get_fw_version(serial, CP210X_GET_FW_VER_2N);
2123 		if (ret)
2124 			break;
2125 		if (priv->fw_version <= 0x10004)
2126 			priv->no_flow_control = true;
2127 		break;
2128 	default:
2129 		break;
2130 	}
2131 }
2132 
2133 static int cp210x_attach(struct usb_serial *serial)
2134 {
2135 	int result;
2136 	struct cp210x_serial_private *priv;
2137 
2138 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2139 	if (!priv)
2140 		return -ENOMEM;
2141 
2142 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2143 					  CP210X_GET_PARTNUM, &priv->partnum,
2144 					  sizeof(priv->partnum));
2145 	if (result < 0) {
2146 		dev_warn(&serial->interface->dev,
2147 			 "querying part number failed\n");
2148 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2149 	}
2150 
2151 	usb_set_serial_data(serial, priv);
2152 
2153 	cp210x_determine_quirks(serial);
2154 	cp210x_init_max_speed(serial);
2155 
2156 	result = cp210x_gpio_init(serial);
2157 	if (result < 0) {
2158 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2159 				result);
2160 	}
2161 
2162 	return 0;
2163 }
2164 
2165 static void cp210x_disconnect(struct usb_serial *serial)
2166 {
2167 	cp210x_gpio_remove(serial);
2168 }
2169 
2170 static void cp210x_release(struct usb_serial *serial)
2171 {
2172 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2173 
2174 	cp210x_gpio_remove(serial);
2175 
2176 	kfree(priv);
2177 }
2178 
2179 module_usb_serial_driver(serial_drivers, id_table);
2180 
2181 MODULE_DESCRIPTION(DRIVER_DESC);
2182 MODULE_LICENSE("GPL v2");
2183