xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 3a83e4e6)
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  *
7  * Support to set flow control line levels using TIOCMGET and TIOCMSET
8  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
9  * control thanks to Munir Nassar nassarmu@real-time.com
10  *
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/tty.h>
17 #include <linux/tty_flip.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/usb.h>
21 #include <linux/uaccess.h>
22 #include <linux/usb/serial.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/bitops.h>
25 #include <linux/mutex.h>
26 
27 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
28 
29 /*
30  * Function Prototypes
31  */
32 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
33 static void cp210x_close(struct usb_serial_port *);
34 static void cp210x_get_termios(struct tty_struct *, struct usb_serial_port *);
35 static void cp210x_get_termios_port(struct usb_serial_port *port,
36 	tcflag_t *cflagp, unsigned int *baudp);
37 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
38 							struct ktermios *);
39 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
40 							struct ktermios*);
41 static bool cp210x_tx_empty(struct usb_serial_port *port);
42 static int cp210x_tiocmget(struct tty_struct *);
43 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
44 static int cp210x_tiocmset_port(struct usb_serial_port *port,
45 		unsigned int, unsigned int);
46 static void cp210x_break_ctl(struct tty_struct *, int);
47 static int cp210x_attach(struct usb_serial *);
48 static void cp210x_disconnect(struct usb_serial *);
49 static void cp210x_release(struct usb_serial *);
50 static int cp210x_port_probe(struct usb_serial_port *);
51 static int cp210x_port_remove(struct usb_serial_port *);
52 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
53 static void cp210x_process_read_urb(struct urb *urb);
54 static void cp210x_enable_event_mode(struct usb_serial_port *port);
55 static void cp210x_disable_event_mode(struct usb_serial_port *port);
56 
57 static const struct usb_device_id id_table[] = {
58 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
59 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
60 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
61 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
62 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
63 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
64 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
65 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
66 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
67 	{ USB_DEVICE(0x0B00, 0x3070) }, /* Ingenico 3070 */
68 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
69 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
70 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
71 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
72 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
73 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
74 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
75 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
76 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
77 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
78 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
79 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
80 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
81 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
82 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
83 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
84 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
85 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
86 	{ USB_DEVICE(0x10C4, 0x8056) }, /* Lorenz Messtechnik devices */
87 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
88 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
89 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
90 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
91 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
92 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
93 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
94 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
95 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
96 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
97 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
98 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
99 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
100 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
101 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
102 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
103 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
104 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
105 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
106 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
107 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
108 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
109 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
110 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
111 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
112 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
113 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
114 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
115 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
116 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
117 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
118 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
119 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
120 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
121 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
122 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
123 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
124 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
125 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
126 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
127 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
128 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
129 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
130 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
131 	{ USB_DEVICE(0x10C4, 0x83AA) }, /* Mark-10 Digital Force Gauge */
132 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
133 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
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, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
152 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
153 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
154 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
155 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
156 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
157 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
158 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
159 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
160 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
161 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
162 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
163 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
164 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
165 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
166 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
167 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
168 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
169 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
170 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
171 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
172 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
173 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
174 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
175 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
176 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
177 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
178 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
179 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
180 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
181 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
182 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
183 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
184 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
185 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
186 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
187 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
188 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
189 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
190 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
191 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
192 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
193 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
194 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
195 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
196 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
197 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
198 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
199 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
200 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
201 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
202 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
203 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
204 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
205 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
206 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
207 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
208 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
209 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
210 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
211 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
212 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
213 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
214 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
215 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
216 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
217 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
218 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
219 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
220 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
221 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
222 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
223 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
224 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
227 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
228 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
229 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
230 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
231 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
232 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
233 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
234 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
235 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
236 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
237 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
238 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
239 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
240 	{ } /* Terminating Entry */
241 };
242 
243 MODULE_DEVICE_TABLE(usb, id_table);
244 
245 struct cp210x_serial_private {
246 #ifdef CONFIG_GPIOLIB
247 	struct gpio_chip	gc;
248 	bool			gpio_registered;
249 	u8			gpio_pushpull;
250 	u8			gpio_altfunc;
251 	u8			gpio_input;
252 #endif
253 	u8			partnum;
254 	speed_t			min_speed;
255 	speed_t			max_speed;
256 	bool			use_actual_rate;
257 };
258 
259 enum cp210x_event_state {
260 	ES_DATA,
261 	ES_ESCAPE,
262 	ES_LSR,
263 	ES_LSR_DATA_0,
264 	ES_LSR_DATA_1,
265 	ES_MSR
266 };
267 
268 struct cp210x_port_private {
269 	u8			bInterfaceNumber;
270 	bool			has_swapped_line_ctl;
271 	bool			event_mode;
272 	enum cp210x_event_state event_state;
273 	u8 lsr;
274 };
275 
276 static struct usb_serial_driver cp210x_device = {
277 	.driver = {
278 		.owner =	THIS_MODULE,
279 		.name =		"cp210x",
280 	},
281 	.id_table		= id_table,
282 	.num_ports		= 1,
283 	.bulk_in_size		= 256,
284 	.bulk_out_size		= 256,
285 	.open			= cp210x_open,
286 	.close			= cp210x_close,
287 	.break_ctl		= cp210x_break_ctl,
288 	.set_termios		= cp210x_set_termios,
289 	.tx_empty		= cp210x_tx_empty,
290 	.throttle		= usb_serial_generic_throttle,
291 	.unthrottle		= usb_serial_generic_unthrottle,
292 	.tiocmget		= cp210x_tiocmget,
293 	.tiocmset		= cp210x_tiocmset,
294 	.get_icount		= usb_serial_generic_get_icount,
295 	.attach			= cp210x_attach,
296 	.disconnect		= cp210x_disconnect,
297 	.release		= cp210x_release,
298 	.port_probe		= cp210x_port_probe,
299 	.port_remove		= cp210x_port_remove,
300 	.dtr_rts		= cp210x_dtr_rts,
301 	.process_read_urb	= cp210x_process_read_urb,
302 };
303 
304 static struct usb_serial_driver * const serial_drivers[] = {
305 	&cp210x_device, NULL
306 };
307 
308 /* Config request types */
309 #define REQTYPE_HOST_TO_INTERFACE	0x41
310 #define REQTYPE_INTERFACE_TO_HOST	0xc1
311 #define REQTYPE_HOST_TO_DEVICE	0x40
312 #define REQTYPE_DEVICE_TO_HOST	0xc0
313 
314 /* Config request codes */
315 #define CP210X_IFC_ENABLE	0x00
316 #define CP210X_SET_BAUDDIV	0x01
317 #define CP210X_GET_BAUDDIV	0x02
318 #define CP210X_SET_LINE_CTL	0x03
319 #define CP210X_GET_LINE_CTL	0x04
320 #define CP210X_SET_BREAK	0x05
321 #define CP210X_IMM_CHAR		0x06
322 #define CP210X_SET_MHS		0x07
323 #define CP210X_GET_MDMSTS	0x08
324 #define CP210X_SET_XON		0x09
325 #define CP210X_SET_XOFF		0x0A
326 #define CP210X_SET_EVENTMASK	0x0B
327 #define CP210X_GET_EVENTMASK	0x0C
328 #define CP210X_SET_CHAR		0x0D
329 #define CP210X_GET_CHARS	0x0E
330 #define CP210X_GET_PROPS	0x0F
331 #define CP210X_GET_COMM_STATUS	0x10
332 #define CP210X_RESET		0x11
333 #define CP210X_PURGE		0x12
334 #define CP210X_SET_FLOW		0x13
335 #define CP210X_GET_FLOW		0x14
336 #define CP210X_EMBED_EVENTS	0x15
337 #define CP210X_GET_EVENTSTATE	0x16
338 #define CP210X_SET_CHARS	0x19
339 #define CP210X_GET_BAUDRATE	0x1D
340 #define CP210X_SET_BAUDRATE	0x1E
341 #define CP210X_VENDOR_SPECIFIC	0xFF
342 
343 /* CP210X_IFC_ENABLE */
344 #define UART_ENABLE		0x0001
345 #define UART_DISABLE		0x0000
346 
347 /* CP210X_(SET|GET)_BAUDDIV */
348 #define BAUD_RATE_GEN_FREQ	0x384000
349 
350 /* CP210X_(SET|GET)_LINE_CTL */
351 #define BITS_DATA_MASK		0X0f00
352 #define BITS_DATA_5		0X0500
353 #define BITS_DATA_6		0X0600
354 #define BITS_DATA_7		0X0700
355 #define BITS_DATA_8		0X0800
356 #define BITS_DATA_9		0X0900
357 
358 #define BITS_PARITY_MASK	0x00f0
359 #define BITS_PARITY_NONE	0x0000
360 #define BITS_PARITY_ODD		0x0010
361 #define BITS_PARITY_EVEN	0x0020
362 #define BITS_PARITY_MARK	0x0030
363 #define BITS_PARITY_SPACE	0x0040
364 
365 #define BITS_STOP_MASK		0x000f
366 #define BITS_STOP_1		0x0000
367 #define BITS_STOP_1_5		0x0001
368 #define BITS_STOP_2		0x0002
369 
370 /* CP210X_SET_BREAK */
371 #define BREAK_ON		0x0001
372 #define BREAK_OFF		0x0000
373 
374 /* CP210X_(SET_MHS|GET_MDMSTS) */
375 #define CONTROL_DTR		0x0001
376 #define CONTROL_RTS		0x0002
377 #define CONTROL_CTS		0x0010
378 #define CONTROL_DSR		0x0020
379 #define CONTROL_RING		0x0040
380 #define CONTROL_DCD		0x0080
381 #define CONTROL_WRITE_DTR	0x0100
382 #define CONTROL_WRITE_RTS	0x0200
383 
384 /* CP210X_VENDOR_SPECIFIC values */
385 #define CP210X_READ_2NCONFIG	0x000E
386 #define CP210X_READ_LATCH	0x00C2
387 #define CP210X_GET_PARTNUM	0x370B
388 #define CP210X_GET_PORTCONFIG	0x370C
389 #define CP210X_GET_DEVICEMODE	0x3711
390 #define CP210X_WRITE_LATCH	0x37E1
391 
392 /* Part number definitions */
393 #define CP210X_PARTNUM_CP2101	0x01
394 #define CP210X_PARTNUM_CP2102	0x02
395 #define CP210X_PARTNUM_CP2103	0x03
396 #define CP210X_PARTNUM_CP2104	0x04
397 #define CP210X_PARTNUM_CP2105	0x05
398 #define CP210X_PARTNUM_CP2108	0x08
399 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
400 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
401 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
402 #define CP210X_PARTNUM_UNKNOWN	0xFF
403 
404 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
405 struct cp210x_comm_status {
406 	__le32   ulErrors;
407 	__le32   ulHoldReasons;
408 	__le32   ulAmountInInQueue;
409 	__le32   ulAmountInOutQueue;
410 	u8       bEofReceived;
411 	u8       bWaitForImmediate;
412 	u8       bReserved;
413 } __packed;
414 
415 /*
416  * CP210X_PURGE - 16 bits passed in wValue of USB request.
417  * SiLabs app note AN571 gives a strange description of the 4 bits:
418  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
419  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
420  */
421 #define PURGE_ALL		0x000f
422 
423 /* CP210X_EMBED_EVENTS */
424 #define CP210X_ESCCHAR		0xec
425 
426 #define CP210X_LSR_OVERRUN	BIT(1)
427 #define CP210X_LSR_PARITY	BIT(2)
428 #define CP210X_LSR_FRAME	BIT(3)
429 #define CP210X_LSR_BREAK	BIT(4)
430 
431 
432 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
433 struct cp210x_flow_ctl {
434 	__le32	ulControlHandshake;
435 	__le32	ulFlowReplace;
436 	__le32	ulXonLimit;
437 	__le32	ulXoffLimit;
438 };
439 
440 /* cp210x_flow_ctl::ulControlHandshake */
441 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
442 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
443 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
444 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
445 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
446 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
447 
448 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
449 #define CP210X_SERIAL_DTR_INACTIVE	0
450 #define CP210X_SERIAL_DTR_ACTIVE	1
451 #define CP210X_SERIAL_DTR_FLOW_CTL	2
452 
453 /* cp210x_flow_ctl::ulFlowReplace */
454 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
455 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
456 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
457 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
458 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
459 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
460 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
461 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
462 
463 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
464 #define CP210X_SERIAL_RTS_INACTIVE	0
465 #define CP210X_SERIAL_RTS_ACTIVE	1
466 #define CP210X_SERIAL_RTS_FLOW_CTL	2
467 
468 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
469 struct cp210x_pin_mode {
470 	u8	eci;
471 	u8	sci;
472 };
473 
474 #define CP210X_PIN_MODE_MODEM		0
475 #define CP210X_PIN_MODE_GPIO		BIT(0)
476 
477 /*
478  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
479  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
480  */
481 struct cp210x_dual_port_config {
482 	__le16	gpio_mode;
483 	u8	__pad0[2];
484 	__le16	reset_state;
485 	u8	__pad1[4];
486 	__le16	suspend_state;
487 	u8	sci_cfg;
488 	u8	eci_cfg;
489 	u8	device_cfg;
490 } __packed;
491 
492 /*
493  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
494  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
495  */
496 struct cp210x_single_port_config {
497 	__le16	gpio_mode;
498 	u8	__pad0[2];
499 	__le16	reset_state;
500 	u8	__pad1[4];
501 	__le16	suspend_state;
502 	u8	device_cfg;
503 } __packed;
504 
505 /* GPIO modes */
506 #define CP210X_SCI_GPIO_MODE_OFFSET	9
507 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
508 
509 #define CP210X_ECI_GPIO_MODE_OFFSET	2
510 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
511 
512 #define CP210X_GPIO_MODE_OFFSET		8
513 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
514 
515 /* CP2105 port configuration values */
516 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
517 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
518 #define CP2105_GPIO1_RS485_MODE		BIT(2)
519 
520 /* CP2104 port configuration values */
521 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
522 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
523 #define CP2104_GPIO2_RS485_MODE		BIT(2)
524 
525 /* CP2102N configuration array indices */
526 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
527 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
528 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
529 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
530 
531 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
532 struct cp210x_gpio_write {
533 	u8	mask;
534 	u8	state;
535 };
536 
537 /*
538  * Helper to get interface number when we only have struct usb_serial.
539  */
540 static u8 cp210x_interface_num(struct usb_serial *serial)
541 {
542 	struct usb_host_interface *cur_altsetting;
543 
544 	cur_altsetting = serial->interface->cur_altsetting;
545 
546 	return cur_altsetting->desc.bInterfaceNumber;
547 }
548 
549 /*
550  * Reads a variable-sized block of CP210X_ registers, identified by req.
551  * Returns data into buf in native USB byte order.
552  */
553 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
554 		void *buf, int bufsize)
555 {
556 	struct usb_serial *serial = port->serial;
557 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
558 	void *dmabuf;
559 	int result;
560 
561 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
562 	if (!dmabuf) {
563 		/*
564 		 * FIXME Some callers don't bother to check for error,
565 		 * at least give them consistent junk until they are fixed
566 		 */
567 		memset(buf, 0, bufsize);
568 		return -ENOMEM;
569 	}
570 
571 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
572 			req, REQTYPE_INTERFACE_TO_HOST, 0,
573 			port_priv->bInterfaceNumber, dmabuf, bufsize,
574 			USB_CTRL_SET_TIMEOUT);
575 	if (result == bufsize) {
576 		memcpy(buf, dmabuf, bufsize);
577 		result = 0;
578 	} else {
579 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
580 				req, bufsize, result);
581 		if (result >= 0)
582 			result = -EIO;
583 
584 		/*
585 		 * FIXME Some callers don't bother to check for error,
586 		 * at least give them consistent junk until they are fixed
587 		 */
588 		memset(buf, 0, bufsize);
589 	}
590 
591 	kfree(dmabuf);
592 
593 	return result;
594 }
595 
596 /*
597  * Reads any 32-bit CP210X_ register identified by req.
598  */
599 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
600 {
601 	__le32 le32_val;
602 	int err;
603 
604 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
605 	if (err) {
606 		/*
607 		 * FIXME Some callers don't bother to check for error,
608 		 * at least give them consistent junk until they are fixed
609 		 */
610 		*val = 0;
611 		return err;
612 	}
613 
614 	*val = le32_to_cpu(le32_val);
615 
616 	return 0;
617 }
618 
619 /*
620  * Reads any 16-bit CP210X_ register identified by req.
621  */
622 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
623 {
624 	__le16 le16_val;
625 	int err;
626 
627 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
628 	if (err)
629 		return err;
630 
631 	*val = le16_to_cpu(le16_val);
632 
633 	return 0;
634 }
635 
636 /*
637  * Reads any 8-bit CP210X_ register identified by req.
638  */
639 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
640 {
641 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
642 }
643 
644 /*
645  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
646  * Returns data into buf in native USB byte order.
647  */
648 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
649 				    void *buf, int bufsize)
650 {
651 	void *dmabuf;
652 	int result;
653 
654 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
655 	if (!dmabuf)
656 		return -ENOMEM;
657 
658 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
659 				 CP210X_VENDOR_SPECIFIC, type, val,
660 				 cp210x_interface_num(serial), dmabuf, bufsize,
661 				 USB_CTRL_GET_TIMEOUT);
662 	if (result == bufsize) {
663 		memcpy(buf, dmabuf, bufsize);
664 		result = 0;
665 	} else {
666 		dev_err(&serial->interface->dev,
667 			"failed to get vendor val 0x%04x size %d: %d\n", val,
668 			bufsize, result);
669 		if (result >= 0)
670 			result = -EIO;
671 	}
672 
673 	kfree(dmabuf);
674 
675 	return result;
676 }
677 
678 /*
679  * Writes any 16-bit CP210X_ register (req) whose value is passed
680  * entirely in the wValue field of the USB request.
681  */
682 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
683 {
684 	struct usb_serial *serial = port->serial;
685 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
686 	int result;
687 
688 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
689 			req, REQTYPE_HOST_TO_INTERFACE, val,
690 			port_priv->bInterfaceNumber, NULL, 0,
691 			USB_CTRL_SET_TIMEOUT);
692 	if (result < 0) {
693 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
694 				req, result);
695 	}
696 
697 	return result;
698 }
699 
700 /*
701  * Writes a variable-sized block of CP210X_ registers, identified by req.
702  * Data in buf must be in native USB byte order.
703  */
704 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
705 		void *buf, int bufsize)
706 {
707 	struct usb_serial *serial = port->serial;
708 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
709 	void *dmabuf;
710 	int result;
711 
712 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
713 	if (!dmabuf)
714 		return -ENOMEM;
715 
716 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
717 			req, REQTYPE_HOST_TO_INTERFACE, 0,
718 			port_priv->bInterfaceNumber, dmabuf, bufsize,
719 			USB_CTRL_SET_TIMEOUT);
720 
721 	kfree(dmabuf);
722 
723 	if (result == bufsize) {
724 		result = 0;
725 	} else {
726 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
727 				req, bufsize, result);
728 		if (result >= 0)
729 			result = -EIO;
730 	}
731 
732 	return result;
733 }
734 
735 /*
736  * Writes any 32-bit CP210X_ register identified by req.
737  */
738 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
739 {
740 	__le32 le32_val;
741 
742 	le32_val = cpu_to_le32(val);
743 
744 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
745 }
746 
747 #ifdef CONFIG_GPIOLIB
748 /*
749  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
750  * Data in buf must be in native USB byte order.
751  */
752 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
753 				     u16 val, void *buf, int bufsize)
754 {
755 	void *dmabuf;
756 	int result;
757 
758 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
759 	if (!dmabuf)
760 		return -ENOMEM;
761 
762 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
763 				 CP210X_VENDOR_SPECIFIC, type, val,
764 				 cp210x_interface_num(serial), dmabuf, bufsize,
765 				 USB_CTRL_SET_TIMEOUT);
766 
767 	kfree(dmabuf);
768 
769 	if (result == bufsize) {
770 		result = 0;
771 	} else {
772 		dev_err(&serial->interface->dev,
773 			"failed to set vendor val 0x%04x size %d: %d\n", val,
774 			bufsize, result);
775 		if (result >= 0)
776 			result = -EIO;
777 	}
778 
779 	return result;
780 }
781 #endif
782 
783 /*
784  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
785  * Write a known good value 0x800, read it back.
786  * If it comes back swapped the bug is detected.
787  * Preserve the original register value.
788  */
789 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
790 {
791 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
792 	u16 line_ctl_save;
793 	u16 line_ctl_test;
794 	int err;
795 
796 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
797 	if (err)
798 		return err;
799 
800 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
801 	if (err)
802 		return err;
803 
804 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
805 	if (err)
806 		return err;
807 
808 	if (line_ctl_test == 8) {
809 		port_priv->has_swapped_line_ctl = true;
810 		line_ctl_save = swab16(line_ctl_save);
811 	}
812 
813 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
814 }
815 
816 /*
817  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
818  * to workaround cp2108 bug and get correct value.
819  */
820 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
821 {
822 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
823 	int err;
824 
825 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
826 	if (err)
827 		return err;
828 
829 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
830 	if (port_priv->has_swapped_line_ctl)
831 		*ctl = swab16(*ctl);
832 
833 	return 0;
834 }
835 
836 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
837 {
838 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
839 	int result;
840 
841 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
842 	if (result) {
843 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
844 		return result;
845 	}
846 
847 	/* Configure the termios structure */
848 	cp210x_get_termios(tty, port);
849 
850 	if (tty) {
851 		/* The baud rate must be initialised on cp2104 */
852 		cp210x_change_speed(tty, port, NULL);
853 
854 		if (I_INPCK(tty))
855 			cp210x_enable_event_mode(port);
856 	}
857 
858 	result = usb_serial_generic_open(tty, port);
859 	if (result)
860 		goto err_disable;
861 
862 	return 0;
863 
864 err_disable:
865 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
866 	port_priv->event_mode = false;
867 
868 	return result;
869 }
870 
871 static void cp210x_close(struct usb_serial_port *port)
872 {
873 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
874 
875 	usb_serial_generic_close(port);
876 
877 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
878 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
879 
880 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
881 
882 	/* Disabling the interface disables event-insertion mode. */
883 	port_priv->event_mode = false;
884 }
885 
886 static void cp210x_process_lsr(struct usb_serial_port *port, unsigned char lsr, char *flag)
887 {
888 	if (lsr & CP210X_LSR_BREAK) {
889 		port->icount.brk++;
890 		*flag = TTY_BREAK;
891 	} else if (lsr & CP210X_LSR_PARITY) {
892 		port->icount.parity++;
893 		*flag = TTY_PARITY;
894 	} else if (lsr & CP210X_LSR_FRAME) {
895 		port->icount.frame++;
896 		*flag = TTY_FRAME;
897 	}
898 
899 	if (lsr & CP210X_LSR_OVERRUN) {
900 		port->icount.overrun++;
901 		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
902 	}
903 }
904 
905 static bool cp210x_process_char(struct usb_serial_port *port, unsigned char *ch, char *flag)
906 {
907 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
908 
909 	switch (port_priv->event_state) {
910 	case ES_DATA:
911 		if (*ch == CP210X_ESCCHAR) {
912 			port_priv->event_state = ES_ESCAPE;
913 			break;
914 		}
915 		return false;
916 	case ES_ESCAPE:
917 		switch (*ch) {
918 		case 0:
919 			dev_dbg(&port->dev, "%s - escape char\n", __func__);
920 			*ch = CP210X_ESCCHAR;
921 			port_priv->event_state = ES_DATA;
922 			return false;
923 		case 1:
924 			port_priv->event_state = ES_LSR_DATA_0;
925 			break;
926 		case 2:
927 			port_priv->event_state = ES_LSR;
928 			break;
929 		case 3:
930 			port_priv->event_state = ES_MSR;
931 			break;
932 		default:
933 			dev_err(&port->dev, "malformed event 0x%02x\n", *ch);
934 			port_priv->event_state = ES_DATA;
935 			break;
936 		}
937 		break;
938 	case ES_LSR_DATA_0:
939 		port_priv->lsr = *ch;
940 		port_priv->event_state = ES_LSR_DATA_1;
941 		break;
942 	case ES_LSR_DATA_1:
943 		dev_dbg(&port->dev, "%s - lsr = 0x%02x, data = 0x%02x\n",
944 				__func__, port_priv->lsr, *ch);
945 		cp210x_process_lsr(port, port_priv->lsr, flag);
946 		port_priv->event_state = ES_DATA;
947 		return false;
948 	case ES_LSR:
949 		dev_dbg(&port->dev, "%s - lsr = 0x%02x\n", __func__, *ch);
950 		port_priv->lsr = *ch;
951 		cp210x_process_lsr(port, port_priv->lsr, flag);
952 		port_priv->event_state = ES_DATA;
953 		break;
954 	case ES_MSR:
955 		dev_dbg(&port->dev, "%s - msr = 0x%02x\n", __func__, *ch);
956 		/* unimplemented */
957 		port_priv->event_state = ES_DATA;
958 		break;
959 	}
960 
961 	return true;
962 }
963 
964 static void cp210x_process_read_urb(struct urb *urb)
965 {
966 	struct usb_serial_port *port = urb->context;
967 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
968 	unsigned char *ch = urb->transfer_buffer;
969 	char flag;
970 	int i;
971 
972 	if (!urb->actual_length)
973 		return;
974 
975 	if (port_priv->event_mode) {
976 		for (i = 0; i < urb->actual_length; i++, ch++) {
977 			flag = TTY_NORMAL;
978 
979 			if (cp210x_process_char(port, ch, &flag))
980 				continue;
981 
982 			tty_insert_flip_char(&port->port, *ch, flag);
983 		}
984 	} else {
985 		tty_insert_flip_string(&port->port, ch, urb->actual_length);
986 	}
987 	tty_flip_buffer_push(&port->port);
988 }
989 
990 /*
991  * Read how many bytes are waiting in the TX queue.
992  */
993 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
994 		u32 *count)
995 {
996 	struct usb_serial *serial = port->serial;
997 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
998 	struct cp210x_comm_status *sts;
999 	int result;
1000 
1001 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
1002 	if (!sts)
1003 		return -ENOMEM;
1004 
1005 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
1006 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
1007 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
1008 			USB_CTRL_GET_TIMEOUT);
1009 	if (result == sizeof(*sts)) {
1010 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
1011 		result = 0;
1012 	} else {
1013 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
1014 		if (result >= 0)
1015 			result = -EIO;
1016 	}
1017 
1018 	kfree(sts);
1019 
1020 	return result;
1021 }
1022 
1023 static bool cp210x_tx_empty(struct usb_serial_port *port)
1024 {
1025 	int err;
1026 	u32 count;
1027 
1028 	err = cp210x_get_tx_queue_byte_count(port, &count);
1029 	if (err)
1030 		return true;
1031 
1032 	return !count;
1033 }
1034 
1035 /*
1036  * cp210x_get_termios
1037  * Reads the baud rate, data bits, parity, stop bits and flow control mode
1038  * from the device, corrects any unsupported values, and configures the
1039  * termios structure to reflect the state of the device
1040  */
1041 static void cp210x_get_termios(struct tty_struct *tty,
1042 	struct usb_serial_port *port)
1043 {
1044 	unsigned int baud;
1045 
1046 	if (tty) {
1047 		cp210x_get_termios_port(tty->driver_data,
1048 			&tty->termios.c_cflag, &baud);
1049 		tty_encode_baud_rate(tty, baud, baud);
1050 	} else {
1051 		tcflag_t cflag;
1052 		cflag = 0;
1053 		cp210x_get_termios_port(port, &cflag, &baud);
1054 	}
1055 }
1056 
1057 /*
1058  * cp210x_get_termios_port
1059  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
1060  */
1061 static void cp210x_get_termios_port(struct usb_serial_port *port,
1062 	tcflag_t *cflagp, unsigned int *baudp)
1063 {
1064 	struct device *dev = &port->dev;
1065 	tcflag_t cflag;
1066 	struct cp210x_flow_ctl flow_ctl;
1067 	u32 baud;
1068 	u16 bits;
1069 	u32 ctl_hs;
1070 	u32 flow_repl;
1071 
1072 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
1073 
1074 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
1075 	*baudp = baud;
1076 
1077 	cflag = *cflagp;
1078 
1079 	cp210x_get_line_ctl(port, &bits);
1080 	cflag &= ~CSIZE;
1081 	switch (bits & BITS_DATA_MASK) {
1082 	case BITS_DATA_5:
1083 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
1084 		cflag |= CS5;
1085 		break;
1086 	case BITS_DATA_6:
1087 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
1088 		cflag |= CS6;
1089 		break;
1090 	case BITS_DATA_7:
1091 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
1092 		cflag |= CS7;
1093 		break;
1094 	case BITS_DATA_8:
1095 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
1096 		cflag |= CS8;
1097 		break;
1098 	case BITS_DATA_9:
1099 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
1100 		cflag |= CS8;
1101 		bits &= ~BITS_DATA_MASK;
1102 		bits |= BITS_DATA_8;
1103 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1104 		break;
1105 	default:
1106 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
1107 		cflag |= CS8;
1108 		bits &= ~BITS_DATA_MASK;
1109 		bits |= BITS_DATA_8;
1110 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1111 		break;
1112 	}
1113 
1114 	switch (bits & BITS_PARITY_MASK) {
1115 	case BITS_PARITY_NONE:
1116 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
1117 		cflag &= ~PARENB;
1118 		break;
1119 	case BITS_PARITY_ODD:
1120 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
1121 		cflag |= (PARENB|PARODD);
1122 		break;
1123 	case BITS_PARITY_EVEN:
1124 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1125 		cflag &= ~PARODD;
1126 		cflag |= PARENB;
1127 		break;
1128 	case BITS_PARITY_MARK:
1129 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
1130 		cflag |= (PARENB|PARODD|CMSPAR);
1131 		break;
1132 	case BITS_PARITY_SPACE:
1133 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1134 		cflag &= ~PARODD;
1135 		cflag |= (PARENB|CMSPAR);
1136 		break;
1137 	default:
1138 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
1139 		cflag &= ~PARENB;
1140 		bits &= ~BITS_PARITY_MASK;
1141 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1142 		break;
1143 	}
1144 
1145 	cflag &= ~CSTOPB;
1146 	switch (bits & BITS_STOP_MASK) {
1147 	case BITS_STOP_1:
1148 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1149 		break;
1150 	case BITS_STOP_1_5:
1151 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
1152 		bits &= ~BITS_STOP_MASK;
1153 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1154 		break;
1155 	case BITS_STOP_2:
1156 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1157 		cflag |= CSTOPB;
1158 		break;
1159 	default:
1160 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
1161 		bits &= ~BITS_STOP_MASK;
1162 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1163 		break;
1164 	}
1165 
1166 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1167 			sizeof(flow_ctl));
1168 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1169 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1170 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1171 		/*
1172 		 * When the port is closed, the CP210x hardware disables
1173 		 * auto-RTS and RTS is deasserted but it leaves auto-CTS when
1174 		 * in hardware flow control mode. When re-opening the port, if
1175 		 * auto-CTS is enabled on the cp210x, then auto-RTS must be
1176 		 * re-enabled in the driver.
1177 		 */
1178 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1179 		flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1180 		flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
1181 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1182 		cp210x_write_reg_block(port,
1183 				CP210X_SET_FLOW,
1184 				&flow_ctl,
1185 				sizeof(flow_ctl));
1186 
1187 		cflag |= CRTSCTS;
1188 	} else {
1189 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1190 		cflag &= ~CRTSCTS;
1191 	}
1192 
1193 	*cflagp = cflag;
1194 }
1195 
1196 struct cp210x_rate {
1197 	speed_t rate;
1198 	speed_t high;
1199 };
1200 
1201 static const struct cp210x_rate cp210x_an205_table1[] = {
1202 	{ 300, 300 },
1203 	{ 600, 600 },
1204 	{ 1200, 1200 },
1205 	{ 1800, 1800 },
1206 	{ 2400, 2400 },
1207 	{ 4000, 4000 },
1208 	{ 4800, 4803 },
1209 	{ 7200, 7207 },
1210 	{ 9600, 9612 },
1211 	{ 14400, 14428 },
1212 	{ 16000, 16062 },
1213 	{ 19200, 19250 },
1214 	{ 28800, 28912 },
1215 	{ 38400, 38601 },
1216 	{ 51200, 51558 },
1217 	{ 56000, 56280 },
1218 	{ 57600, 58053 },
1219 	{ 64000, 64111 },
1220 	{ 76800, 77608 },
1221 	{ 115200, 117028 },
1222 	{ 128000, 129347 },
1223 	{ 153600, 156868 },
1224 	{ 230400, 237832 },
1225 	{ 250000, 254234 },
1226 	{ 256000, 273066 },
1227 	{ 460800, 491520 },
1228 	{ 500000, 567138 },
1229 	{ 576000, 670254 },
1230 	{ 921600, UINT_MAX }
1231 };
1232 
1233 /*
1234  * Quantises the baud rate as per AN205 Table 1
1235  */
1236 static speed_t cp210x_get_an205_rate(speed_t baud)
1237 {
1238 	int i;
1239 
1240 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1241 		if (baud <= cp210x_an205_table1[i].high)
1242 			break;
1243 	}
1244 
1245 	return cp210x_an205_table1[i].rate;
1246 }
1247 
1248 static speed_t cp210x_get_actual_rate(speed_t baud)
1249 {
1250 	unsigned int prescale = 1;
1251 	unsigned int div;
1252 
1253 	if (baud <= 365)
1254 		prescale = 4;
1255 
1256 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1257 	baud = 48000000 / (2 * prescale * div);
1258 
1259 	return baud;
1260 }
1261 
1262 /*
1263  * CP2101 supports the following baud rates:
1264  *
1265  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1266  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1267  *
1268  * CP2102 and CP2103 support the following additional rates:
1269  *
1270  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1271  *	576000
1272  *
1273  * The device will map a requested rate to a supported one, but the result
1274  * of requests for rates greater than 1053257 is undefined (see AN205).
1275  *
1276  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1277  * respectively, with an error less than 1%. The actual rates are determined
1278  * by
1279  *
1280  *	div = round(freq / (2 x prescale x request))
1281  *	actual = freq / (2 x prescale x div)
1282  *
1283  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1284  * or 1 otherwise.
1285  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1286  * otherwise.
1287  */
1288 static void cp210x_change_speed(struct tty_struct *tty,
1289 		struct usb_serial_port *port, struct ktermios *old_termios)
1290 {
1291 	struct usb_serial *serial = port->serial;
1292 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1293 	u32 baud;
1294 
1295 	/*
1296 	 * This maps the requested rate to the actual rate, a valid rate on
1297 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1298 	 *
1299 	 * NOTE: B0 is not implemented.
1300 	 */
1301 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1302 
1303 	if (priv->use_actual_rate)
1304 		baud = cp210x_get_actual_rate(baud);
1305 	else if (baud < 1000000)
1306 		baud = cp210x_get_an205_rate(baud);
1307 
1308 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1309 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1310 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1311 		if (old_termios)
1312 			baud = old_termios->c_ospeed;
1313 		else
1314 			baud = 9600;
1315 	}
1316 
1317 	tty_encode_baud_rate(tty, baud, baud);
1318 }
1319 
1320 static void cp210x_enable_event_mode(struct usb_serial_port *port)
1321 {
1322 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1323 	int ret;
1324 
1325 	if (port_priv->event_mode)
1326 		return;
1327 
1328 	port_priv->event_state = ES_DATA;
1329 	port_priv->event_mode = true;
1330 
1331 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, CP210X_ESCCHAR);
1332 	if (ret) {
1333 		dev_err(&port->dev, "failed to enable events: %d\n", ret);
1334 		port_priv->event_mode = false;
1335 	}
1336 }
1337 
1338 static void cp210x_disable_event_mode(struct usb_serial_port *port)
1339 {
1340 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
1341 	int ret;
1342 
1343 	if (!port_priv->event_mode)
1344 		return;
1345 
1346 	ret = cp210x_write_u16_reg(port, CP210X_EMBED_EVENTS, 0);
1347 	if (ret) {
1348 		dev_err(&port->dev, "failed to disable events: %d\n", ret);
1349 		return;
1350 	}
1351 
1352 	port_priv->event_mode = false;
1353 }
1354 
1355 static void cp210x_set_termios(struct tty_struct *tty,
1356 		struct usb_serial_port *port, struct ktermios *old_termios)
1357 {
1358 	struct device *dev = &port->dev;
1359 	unsigned int cflag, old_cflag;
1360 	u16 bits;
1361 
1362 	cflag = tty->termios.c_cflag;
1363 	old_cflag = old_termios->c_cflag;
1364 
1365 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1366 		cp210x_change_speed(tty, port, old_termios);
1367 
1368 	/* If the number of data bits is to be updated */
1369 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1370 		cp210x_get_line_ctl(port, &bits);
1371 		bits &= ~BITS_DATA_MASK;
1372 		switch (cflag & CSIZE) {
1373 		case CS5:
1374 			bits |= BITS_DATA_5;
1375 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1376 			break;
1377 		case CS6:
1378 			bits |= BITS_DATA_6;
1379 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1380 			break;
1381 		case CS7:
1382 			bits |= BITS_DATA_7;
1383 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1384 			break;
1385 		case CS8:
1386 		default:
1387 			bits |= BITS_DATA_8;
1388 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1389 			break;
1390 		}
1391 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1392 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1393 	}
1394 
1395 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1396 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1397 		cp210x_get_line_ctl(port, &bits);
1398 		bits &= ~BITS_PARITY_MASK;
1399 		if (cflag & PARENB) {
1400 			if (cflag & CMSPAR) {
1401 				if (cflag & PARODD) {
1402 					bits |= BITS_PARITY_MARK;
1403 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1404 				} else {
1405 					bits |= BITS_PARITY_SPACE;
1406 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1407 				}
1408 			} else {
1409 				if (cflag & PARODD) {
1410 					bits |= BITS_PARITY_ODD;
1411 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1412 				} else {
1413 					bits |= BITS_PARITY_EVEN;
1414 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1415 				}
1416 			}
1417 		}
1418 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1419 			dev_dbg(dev, "Parity mode not supported by device\n");
1420 	}
1421 
1422 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1423 		cp210x_get_line_ctl(port, &bits);
1424 		bits &= ~BITS_STOP_MASK;
1425 		if (cflag & CSTOPB) {
1426 			bits |= BITS_STOP_2;
1427 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1428 		} else {
1429 			bits |= BITS_STOP_1;
1430 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1431 		}
1432 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1433 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1434 	}
1435 
1436 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1437 		struct cp210x_flow_ctl flow_ctl;
1438 		u32 ctl_hs;
1439 		u32 flow_repl;
1440 
1441 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1442 				sizeof(flow_ctl));
1443 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1444 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1445 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1446 				__func__, ctl_hs, flow_repl);
1447 
1448 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1449 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1450 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1451 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1452 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1453 		if (cflag & CRTSCTS) {
1454 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1455 
1456 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1457 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1458 					CP210X_SERIAL_RTS_FLOW_CTL);
1459 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1460 		} else {
1461 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1462 
1463 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1464 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1465 					CP210X_SERIAL_RTS_ACTIVE);
1466 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1467 		}
1468 
1469 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1470 				__func__, ctl_hs, flow_repl);
1471 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1472 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1473 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1474 				sizeof(flow_ctl));
1475 	}
1476 
1477 	/*
1478 	 * Enable event-insertion mode only if input parity checking is
1479 	 * enabled for now.
1480 	 */
1481 	if (I_INPCK(tty))
1482 		cp210x_enable_event_mode(port);
1483 	else
1484 		cp210x_disable_event_mode(port);
1485 }
1486 
1487 static int cp210x_tiocmset(struct tty_struct *tty,
1488 		unsigned int set, unsigned int clear)
1489 {
1490 	struct usb_serial_port *port = tty->driver_data;
1491 	return cp210x_tiocmset_port(port, set, clear);
1492 }
1493 
1494 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1495 		unsigned int set, unsigned int clear)
1496 {
1497 	u16 control = 0;
1498 
1499 	if (set & TIOCM_RTS) {
1500 		control |= CONTROL_RTS;
1501 		control |= CONTROL_WRITE_RTS;
1502 	}
1503 	if (set & TIOCM_DTR) {
1504 		control |= CONTROL_DTR;
1505 		control |= CONTROL_WRITE_DTR;
1506 	}
1507 	if (clear & TIOCM_RTS) {
1508 		control &= ~CONTROL_RTS;
1509 		control |= CONTROL_WRITE_RTS;
1510 	}
1511 	if (clear & TIOCM_DTR) {
1512 		control &= ~CONTROL_DTR;
1513 		control |= CONTROL_WRITE_DTR;
1514 	}
1515 
1516 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1517 
1518 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1519 }
1520 
1521 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1522 {
1523 	if (on)
1524 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1525 	else
1526 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1527 }
1528 
1529 static int cp210x_tiocmget(struct tty_struct *tty)
1530 {
1531 	struct usb_serial_port *port = tty->driver_data;
1532 	u8 control;
1533 	int result;
1534 
1535 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1536 	if (result)
1537 		return result;
1538 
1539 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1540 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1541 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1542 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1543 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1544 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1545 
1546 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1547 
1548 	return result;
1549 }
1550 
1551 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1552 {
1553 	struct usb_serial_port *port = tty->driver_data;
1554 	u16 state;
1555 
1556 	if (break_state == 0)
1557 		state = BREAK_OFF;
1558 	else
1559 		state = BREAK_ON;
1560 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1561 		state == BREAK_OFF ? "off" : "on");
1562 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1563 }
1564 
1565 #ifdef CONFIG_GPIOLIB
1566 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1567 {
1568 	struct usb_serial *serial = gpiochip_get_data(gc);
1569 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1570 
1571 	if (priv->gpio_altfunc & BIT(offset))
1572 		return -ENODEV;
1573 
1574 	return 0;
1575 }
1576 
1577 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1578 {
1579 	struct usb_serial *serial = gpiochip_get_data(gc);
1580 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1581 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1582 	int result;
1583 	u8 buf;
1584 
1585 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1586 		req_type = REQTYPE_INTERFACE_TO_HOST;
1587 
1588 	result = usb_autopm_get_interface(serial->interface);
1589 	if (result)
1590 		return result;
1591 
1592 	result = cp210x_read_vendor_block(serial, req_type,
1593 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1594 	usb_autopm_put_interface(serial->interface);
1595 	if (result < 0)
1596 		return result;
1597 
1598 	return !!(buf & BIT(gpio));
1599 }
1600 
1601 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1602 {
1603 	struct usb_serial *serial = gpiochip_get_data(gc);
1604 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1605 	struct cp210x_gpio_write buf;
1606 	int result;
1607 
1608 	if (value == 1)
1609 		buf.state = BIT(gpio);
1610 	else
1611 		buf.state = 0;
1612 
1613 	buf.mask = BIT(gpio);
1614 
1615 	result = usb_autopm_get_interface(serial->interface);
1616 	if (result)
1617 		goto out;
1618 
1619 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1620 		result = cp210x_write_vendor_block(serial,
1621 						   REQTYPE_HOST_TO_INTERFACE,
1622 						   CP210X_WRITE_LATCH, &buf,
1623 						   sizeof(buf));
1624 	} else {
1625 		u16 wIndex = buf.state << 8 | buf.mask;
1626 
1627 		result = usb_control_msg(serial->dev,
1628 					 usb_sndctrlpipe(serial->dev, 0),
1629 					 CP210X_VENDOR_SPECIFIC,
1630 					 REQTYPE_HOST_TO_DEVICE,
1631 					 CP210X_WRITE_LATCH,
1632 					 wIndex,
1633 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1634 	}
1635 
1636 	usb_autopm_put_interface(serial->interface);
1637 out:
1638 	if (result < 0) {
1639 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1640 				result);
1641 	}
1642 }
1643 
1644 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1645 {
1646 	struct usb_serial *serial = gpiochip_get_data(gc);
1647 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1648 
1649 	return priv->gpio_input & BIT(gpio);
1650 }
1651 
1652 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1653 {
1654 	struct usb_serial *serial = gpiochip_get_data(gc);
1655 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1656 
1657 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1658 		/* hardware does not support an input mode */
1659 		return -ENOTSUPP;
1660 	}
1661 
1662 	/* push-pull pins cannot be changed to be inputs */
1663 	if (priv->gpio_pushpull & BIT(gpio))
1664 		return -EINVAL;
1665 
1666 	/* make sure to release pin if it is being driven low */
1667 	cp210x_gpio_set(gc, gpio, 1);
1668 
1669 	priv->gpio_input |= BIT(gpio);
1670 
1671 	return 0;
1672 }
1673 
1674 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1675 					int value)
1676 {
1677 	struct usb_serial *serial = gpiochip_get_data(gc);
1678 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1679 
1680 	priv->gpio_input &= ~BIT(gpio);
1681 	cp210x_gpio_set(gc, gpio, value);
1682 
1683 	return 0;
1684 }
1685 
1686 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1687 				  unsigned long config)
1688 {
1689 	struct usb_serial *serial = gpiochip_get_data(gc);
1690 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1691 	enum pin_config_param param = pinconf_to_config_param(config);
1692 
1693 	/* Succeed only if in correct mode (this can't be set at runtime) */
1694 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1695 	    (priv->gpio_pushpull & BIT(gpio)))
1696 		return 0;
1697 
1698 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1699 	    !(priv->gpio_pushpull & BIT(gpio)))
1700 		return 0;
1701 
1702 	return -ENOTSUPP;
1703 }
1704 
1705 /*
1706  * This function is for configuring GPIO using shared pins, where other signals
1707  * are made unavailable by configuring the use of GPIO. This is believed to be
1708  * only applicable to the cp2105 at this point, the other devices supported by
1709  * this driver that provide GPIO do so in a way that does not impact other
1710  * signals and are thus expected to have very different initialisation.
1711  */
1712 static int cp2105_gpioconf_init(struct usb_serial *serial)
1713 {
1714 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1715 	struct cp210x_pin_mode mode;
1716 	struct cp210x_dual_port_config config;
1717 	u8 intf_num = cp210x_interface_num(serial);
1718 	u8 iface_config;
1719 	int result;
1720 
1721 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1722 					  CP210X_GET_DEVICEMODE, &mode,
1723 					  sizeof(mode));
1724 	if (result < 0)
1725 		return result;
1726 
1727 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1728 					  CP210X_GET_PORTCONFIG, &config,
1729 					  sizeof(config));
1730 	if (result < 0)
1731 		return result;
1732 
1733 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1734 	if (intf_num == 0) {
1735 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1736 			/* mark all GPIOs of this interface as reserved */
1737 			priv->gpio_altfunc = 0xff;
1738 			return 0;
1739 		}
1740 
1741 		iface_config = config.eci_cfg;
1742 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1743 						CP210X_ECI_GPIO_MODE_MASK) >>
1744 						CP210X_ECI_GPIO_MODE_OFFSET);
1745 		priv->gc.ngpio = 2;
1746 	} else if (intf_num == 1) {
1747 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1748 			/* mark all GPIOs of this interface as reserved */
1749 			priv->gpio_altfunc = 0xff;
1750 			return 0;
1751 		}
1752 
1753 		iface_config = config.sci_cfg;
1754 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1755 						CP210X_SCI_GPIO_MODE_MASK) >>
1756 						CP210X_SCI_GPIO_MODE_OFFSET);
1757 		priv->gc.ngpio = 3;
1758 	} else {
1759 		return -ENODEV;
1760 	}
1761 
1762 	/* mark all pins which are not in GPIO mode */
1763 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1764 		priv->gpio_altfunc |= BIT(0);
1765 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1766 			CP2105_GPIO1_RS485_MODE))
1767 		priv->gpio_altfunc |= BIT(1);
1768 
1769 	/* driver implementation for CP2105 only supports outputs */
1770 	priv->gpio_input = 0;
1771 
1772 	return 0;
1773 }
1774 
1775 static int cp2104_gpioconf_init(struct usb_serial *serial)
1776 {
1777 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1778 	struct cp210x_single_port_config config;
1779 	u8 iface_config;
1780 	u8 gpio_latch;
1781 	int result;
1782 	u8 i;
1783 
1784 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1785 					  CP210X_GET_PORTCONFIG, &config,
1786 					  sizeof(config));
1787 	if (result < 0)
1788 		return result;
1789 
1790 	priv->gc.ngpio = 4;
1791 
1792 	iface_config = config.device_cfg;
1793 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1794 					CP210X_GPIO_MODE_MASK) >>
1795 					CP210X_GPIO_MODE_OFFSET);
1796 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1797 					CP210X_GPIO_MODE_MASK) >>
1798 					CP210X_GPIO_MODE_OFFSET);
1799 
1800 	/* mark all pins which are not in GPIO mode */
1801 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1802 		priv->gpio_altfunc |= BIT(0);
1803 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1804 		priv->gpio_altfunc |= BIT(1);
1805 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1806 		priv->gpio_altfunc |= BIT(2);
1807 
1808 	/*
1809 	 * Like CP2102N, CP2104 has also no strict input and output pin
1810 	 * modes.
1811 	 * Do the same input mode emulation as CP2102N.
1812 	 */
1813 	for (i = 0; i < priv->gc.ngpio; ++i) {
1814 		/*
1815 		 * Set direction to "input" iff pin is open-drain and reset
1816 		 * value is 1.
1817 		 */
1818 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1819 			priv->gpio_input |= BIT(i);
1820 	}
1821 
1822 	return 0;
1823 }
1824 
1825 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1826 {
1827 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1828 	const u16 config_size = 0x02a6;
1829 	u8 gpio_rst_latch;
1830 	u8 config_version;
1831 	u8 gpio_pushpull;
1832 	u8 *config_buf;
1833 	u8 gpio_latch;
1834 	u8 gpio_ctrl;
1835 	int result;
1836 	u8 i;
1837 
1838 	/*
1839 	 * Retrieve device configuration from the device.
1840 	 * The array received contains all customization settings done at the
1841 	 * factory/manufacturer. Format of the array is documented at the
1842 	 * time of writing at:
1843 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1844 	 */
1845 	config_buf = kmalloc(config_size, GFP_KERNEL);
1846 	if (!config_buf)
1847 		return -ENOMEM;
1848 
1849 	result = cp210x_read_vendor_block(serial,
1850 					  REQTYPE_DEVICE_TO_HOST,
1851 					  CP210X_READ_2NCONFIG,
1852 					  config_buf,
1853 					  config_size);
1854 	if (result < 0) {
1855 		kfree(config_buf);
1856 		return result;
1857 	}
1858 
1859 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1860 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1861 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1862 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1863 
1864 	kfree(config_buf);
1865 
1866 	/* Make sure this is a config format we understand. */
1867 	if (config_version != 0x01)
1868 		return -ENOTSUPP;
1869 
1870 	priv->gc.ngpio = 4;
1871 
1872 	/*
1873 	 * Get default pin states after reset. Needed so we can determine
1874 	 * the direction of an open-drain pin.
1875 	 */
1876 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1877 
1878 	/* 0 indicates open-drain mode, 1 is push-pull */
1879 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1880 
1881 	/* 0 indicates GPIO mode, 1 is alternate function */
1882 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1883 
1884 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1885 		/*
1886 		 * For the QFN28 package, GPIO4-6 are controlled by
1887 		 * the low three bits of the mode/latch fields.
1888 		 * Contrary to the document linked above, the bits for
1889 		 * the SUSPEND pins are elsewhere.  No alternate
1890 		 * function is available for these pins.
1891 		 */
1892 		priv->gc.ngpio = 7;
1893 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1894 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1895 	}
1896 
1897 	/*
1898 	 * The CP2102N does not strictly has input and output pin modes,
1899 	 * it only knows open-drain and push-pull modes which is set at
1900 	 * factory. An open-drain pin can function both as an
1901 	 * input or an output. We emulate input mode for open-drain pins
1902 	 * by making sure they are not driven low, and we do not allow
1903 	 * push-pull pins to be set as an input.
1904 	 */
1905 	for (i = 0; i < priv->gc.ngpio; ++i) {
1906 		/*
1907 		 * Set direction to "input" iff pin is open-drain and reset
1908 		 * value is 1.
1909 		 */
1910 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1911 			priv->gpio_input |= BIT(i);
1912 	}
1913 
1914 	return 0;
1915 }
1916 
1917 static int cp210x_gpio_init(struct usb_serial *serial)
1918 {
1919 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1920 	int result;
1921 
1922 	switch (priv->partnum) {
1923 	case CP210X_PARTNUM_CP2104:
1924 		result = cp2104_gpioconf_init(serial);
1925 		break;
1926 	case CP210X_PARTNUM_CP2105:
1927 		result = cp2105_gpioconf_init(serial);
1928 		break;
1929 	case CP210X_PARTNUM_CP2102N_QFN28:
1930 	case CP210X_PARTNUM_CP2102N_QFN24:
1931 	case CP210X_PARTNUM_CP2102N_QFN20:
1932 		result = cp2102n_gpioconf_init(serial);
1933 		break;
1934 	default:
1935 		return 0;
1936 	}
1937 
1938 	if (result < 0)
1939 		return result;
1940 
1941 	priv->gc.label = "cp210x";
1942 	priv->gc.request = cp210x_gpio_request;
1943 	priv->gc.get_direction = cp210x_gpio_direction_get;
1944 	priv->gc.direction_input = cp210x_gpio_direction_input;
1945 	priv->gc.direction_output = cp210x_gpio_direction_output;
1946 	priv->gc.get = cp210x_gpio_get;
1947 	priv->gc.set = cp210x_gpio_set;
1948 	priv->gc.set_config = cp210x_gpio_set_config;
1949 	priv->gc.owner = THIS_MODULE;
1950 	priv->gc.parent = &serial->interface->dev;
1951 	priv->gc.base = -1;
1952 	priv->gc.can_sleep = true;
1953 
1954 	result = gpiochip_add_data(&priv->gc, serial);
1955 	if (!result)
1956 		priv->gpio_registered = true;
1957 
1958 	return result;
1959 }
1960 
1961 static void cp210x_gpio_remove(struct usb_serial *serial)
1962 {
1963 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1964 
1965 	if (priv->gpio_registered) {
1966 		gpiochip_remove(&priv->gc);
1967 		priv->gpio_registered = false;
1968 	}
1969 }
1970 
1971 #else
1972 
1973 static int cp210x_gpio_init(struct usb_serial *serial)
1974 {
1975 	return 0;
1976 }
1977 
1978 static void cp210x_gpio_remove(struct usb_serial *serial)
1979 {
1980 	/* Nothing to do */
1981 }
1982 
1983 #endif
1984 
1985 static int cp210x_port_probe(struct usb_serial_port *port)
1986 {
1987 	struct usb_serial *serial = port->serial;
1988 	struct cp210x_port_private *port_priv;
1989 	int ret;
1990 
1991 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1992 	if (!port_priv)
1993 		return -ENOMEM;
1994 
1995 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1996 
1997 	usb_set_serial_port_data(port, port_priv);
1998 
1999 	ret = cp210x_detect_swapped_line_ctl(port);
2000 	if (ret) {
2001 		kfree(port_priv);
2002 		return ret;
2003 	}
2004 
2005 	return 0;
2006 }
2007 
2008 static int cp210x_port_remove(struct usb_serial_port *port)
2009 {
2010 	struct cp210x_port_private *port_priv;
2011 
2012 	port_priv = usb_get_serial_port_data(port);
2013 	kfree(port_priv);
2014 
2015 	return 0;
2016 }
2017 
2018 static void cp210x_init_max_speed(struct usb_serial *serial)
2019 {
2020 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2021 	bool use_actual_rate = false;
2022 	speed_t min = 300;
2023 	speed_t max;
2024 
2025 	switch (priv->partnum) {
2026 	case CP210X_PARTNUM_CP2101:
2027 		max = 921600;
2028 		break;
2029 	case CP210X_PARTNUM_CP2102:
2030 	case CP210X_PARTNUM_CP2103:
2031 		max = 1000000;
2032 		break;
2033 	case CP210X_PARTNUM_CP2104:
2034 		use_actual_rate = true;
2035 		max = 2000000;
2036 		break;
2037 	case CP210X_PARTNUM_CP2108:
2038 		max = 2000000;
2039 		break;
2040 	case CP210X_PARTNUM_CP2105:
2041 		if (cp210x_interface_num(serial) == 0) {
2042 			use_actual_rate = true;
2043 			max = 2000000;	/* ECI */
2044 		} else {
2045 			min = 2400;
2046 			max = 921600;	/* SCI */
2047 		}
2048 		break;
2049 	case CP210X_PARTNUM_CP2102N_QFN28:
2050 	case CP210X_PARTNUM_CP2102N_QFN24:
2051 	case CP210X_PARTNUM_CP2102N_QFN20:
2052 		use_actual_rate = true;
2053 		max = 3000000;
2054 		break;
2055 	default:
2056 		max = 2000000;
2057 		break;
2058 	}
2059 
2060 	priv->min_speed = min;
2061 	priv->max_speed = max;
2062 	priv->use_actual_rate = use_actual_rate;
2063 }
2064 
2065 static int cp210x_attach(struct usb_serial *serial)
2066 {
2067 	int result;
2068 	struct cp210x_serial_private *priv;
2069 
2070 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2071 	if (!priv)
2072 		return -ENOMEM;
2073 
2074 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
2075 					  CP210X_GET_PARTNUM, &priv->partnum,
2076 					  sizeof(priv->partnum));
2077 	if (result < 0) {
2078 		dev_warn(&serial->interface->dev,
2079 			 "querying part number failed\n");
2080 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
2081 	}
2082 
2083 	usb_set_serial_data(serial, priv);
2084 
2085 	cp210x_init_max_speed(serial);
2086 
2087 	result = cp210x_gpio_init(serial);
2088 	if (result < 0) {
2089 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
2090 				result);
2091 	}
2092 
2093 	return 0;
2094 }
2095 
2096 static void cp210x_disconnect(struct usb_serial *serial)
2097 {
2098 	cp210x_gpio_remove(serial);
2099 }
2100 
2101 static void cp210x_release(struct usb_serial *serial)
2102 {
2103 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
2104 
2105 	cp210x_gpio_remove(serial);
2106 
2107 	kfree(priv);
2108 }
2109 
2110 module_usb_serial_driver(serial_drivers, id_table);
2111 
2112 MODULE_DESCRIPTION(DRIVER_DESC);
2113 MODULE_LICENSE("GPL v2");
2114