xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 96de2506)
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 
54 static const struct usb_device_id id_table[] = {
55 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
56 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
57 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
58 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
59 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
60 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
61 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
62 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
63 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
64 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
65 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
66 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
67 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
68 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
69 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
70 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
71 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
72 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
73 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
74 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
75 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
76 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
77 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
78 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
79 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
80 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
81 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
82 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
83 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
84 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
85 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
86 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
87 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
88 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
89 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
90 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
91 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
92 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
93 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
94 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
95 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
96 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
97 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
98 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
99 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
100 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
102 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
103 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
104 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
105 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
106 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
107 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
108 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
109 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
110 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
111 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
112 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
113 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
114 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
115 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
116 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
117 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
118 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
119 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
120 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
121 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
122 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
123 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
124 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
125 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
126 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
127 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
128 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
129 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
130 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
131 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
132 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
133 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
134 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
135 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
136 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
137 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
138 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
139 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
140 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
141 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
142 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
143 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
144 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
145 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
146 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
147 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
148 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
149 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
150 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
151 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
152 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
153 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
154 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
155 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
156 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
157 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
158 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
159 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
160 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
161 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
162 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
163 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
164 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
165 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
166 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
167 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
168 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
169 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
170 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
171 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
172 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
173 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
174 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
175 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
176 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
177 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
178 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
179 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
180 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
181 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
182 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
183 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
184 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
185 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
186 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
187 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
188 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
189 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
190 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
191 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
192 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
193 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
194 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
195 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
196 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
197 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
198 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
199 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
200 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
201 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
202 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
203 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
204 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
205 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
206 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
207 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
208 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
209 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
210 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
211 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
212 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
213 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
214 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
215 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
216 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
217 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
218 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
219 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
220 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
221 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
222 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
224 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
225 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
226 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
227 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
228 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
229 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
230 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
231 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
232 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
233 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
234 	{ } /* Terminating Entry */
235 };
236 
237 MODULE_DEVICE_TABLE(usb, id_table);
238 
239 struct cp210x_serial_private {
240 #ifdef CONFIG_GPIOLIB
241 	struct gpio_chip	gc;
242 	bool			gpio_registered;
243 	u8			gpio_pushpull;
244 	u8			gpio_altfunc;
245 	u8			gpio_input;
246 #endif
247 	u8			partnum;
248 	speed_t			max_speed;
249 	bool			use_actual_rate;
250 };
251 
252 struct cp210x_port_private {
253 	__u8			bInterfaceNumber;
254 	bool			has_swapped_line_ctl;
255 };
256 
257 static struct usb_serial_driver cp210x_device = {
258 	.driver = {
259 		.owner =	THIS_MODULE,
260 		.name =		"cp210x",
261 	},
262 	.id_table		= id_table,
263 	.num_ports		= 1,
264 	.bulk_in_size		= 256,
265 	.bulk_out_size		= 256,
266 	.open			= cp210x_open,
267 	.close			= cp210x_close,
268 	.break_ctl		= cp210x_break_ctl,
269 	.set_termios		= cp210x_set_termios,
270 	.tx_empty		= cp210x_tx_empty,
271 	.tiocmget		= cp210x_tiocmget,
272 	.tiocmset		= cp210x_tiocmset,
273 	.attach			= cp210x_attach,
274 	.disconnect		= cp210x_disconnect,
275 	.release		= cp210x_release,
276 	.port_probe		= cp210x_port_probe,
277 	.port_remove		= cp210x_port_remove,
278 	.dtr_rts		= cp210x_dtr_rts
279 };
280 
281 static struct usb_serial_driver * const serial_drivers[] = {
282 	&cp210x_device, NULL
283 };
284 
285 /* Config request types */
286 #define REQTYPE_HOST_TO_INTERFACE	0x41
287 #define REQTYPE_INTERFACE_TO_HOST	0xc1
288 #define REQTYPE_HOST_TO_DEVICE	0x40
289 #define REQTYPE_DEVICE_TO_HOST	0xc0
290 
291 /* Config request codes */
292 #define CP210X_IFC_ENABLE	0x00
293 #define CP210X_SET_BAUDDIV	0x01
294 #define CP210X_GET_BAUDDIV	0x02
295 #define CP210X_SET_LINE_CTL	0x03
296 #define CP210X_GET_LINE_CTL	0x04
297 #define CP210X_SET_BREAK	0x05
298 #define CP210X_IMM_CHAR		0x06
299 #define CP210X_SET_MHS		0x07
300 #define CP210X_GET_MDMSTS	0x08
301 #define CP210X_SET_XON		0x09
302 #define CP210X_SET_XOFF		0x0A
303 #define CP210X_SET_EVENTMASK	0x0B
304 #define CP210X_GET_EVENTMASK	0x0C
305 #define CP210X_SET_CHAR		0x0D
306 #define CP210X_GET_CHARS	0x0E
307 #define CP210X_GET_PROPS	0x0F
308 #define CP210X_GET_COMM_STATUS	0x10
309 #define CP210X_RESET		0x11
310 #define CP210X_PURGE		0x12
311 #define CP210X_SET_FLOW		0x13
312 #define CP210X_GET_FLOW		0x14
313 #define CP210X_EMBED_EVENTS	0x15
314 #define CP210X_GET_EVENTSTATE	0x16
315 #define CP210X_SET_CHARS	0x19
316 #define CP210X_GET_BAUDRATE	0x1D
317 #define CP210X_SET_BAUDRATE	0x1E
318 #define CP210X_VENDOR_SPECIFIC	0xFF
319 
320 /* CP210X_IFC_ENABLE */
321 #define UART_ENABLE		0x0001
322 #define UART_DISABLE		0x0000
323 
324 /* CP210X_(SET|GET)_BAUDDIV */
325 #define BAUD_RATE_GEN_FREQ	0x384000
326 
327 /* CP210X_(SET|GET)_LINE_CTL */
328 #define BITS_DATA_MASK		0X0f00
329 #define BITS_DATA_5		0X0500
330 #define BITS_DATA_6		0X0600
331 #define BITS_DATA_7		0X0700
332 #define BITS_DATA_8		0X0800
333 #define BITS_DATA_9		0X0900
334 
335 #define BITS_PARITY_MASK	0x00f0
336 #define BITS_PARITY_NONE	0x0000
337 #define BITS_PARITY_ODD		0x0010
338 #define BITS_PARITY_EVEN	0x0020
339 #define BITS_PARITY_MARK	0x0030
340 #define BITS_PARITY_SPACE	0x0040
341 
342 #define BITS_STOP_MASK		0x000f
343 #define BITS_STOP_1		0x0000
344 #define BITS_STOP_1_5		0x0001
345 #define BITS_STOP_2		0x0002
346 
347 /* CP210X_SET_BREAK */
348 #define BREAK_ON		0x0001
349 #define BREAK_OFF		0x0000
350 
351 /* CP210X_(SET_MHS|GET_MDMSTS) */
352 #define CONTROL_DTR		0x0001
353 #define CONTROL_RTS		0x0002
354 #define CONTROL_CTS		0x0010
355 #define CONTROL_DSR		0x0020
356 #define CONTROL_RING		0x0040
357 #define CONTROL_DCD		0x0080
358 #define CONTROL_WRITE_DTR	0x0100
359 #define CONTROL_WRITE_RTS	0x0200
360 
361 /* CP210X_VENDOR_SPECIFIC values */
362 #define CP210X_READ_2NCONFIG	0x000E
363 #define CP210X_READ_LATCH	0x00C2
364 #define CP210X_GET_PARTNUM	0x370B
365 #define CP210X_GET_PORTCONFIG	0x370C
366 #define CP210X_GET_DEVICEMODE	0x3711
367 #define CP210X_WRITE_LATCH	0x37E1
368 
369 /* Part number definitions */
370 #define CP210X_PARTNUM_CP2101	0x01
371 #define CP210X_PARTNUM_CP2102	0x02
372 #define CP210X_PARTNUM_CP2103	0x03
373 #define CP210X_PARTNUM_CP2104	0x04
374 #define CP210X_PARTNUM_CP2105	0x05
375 #define CP210X_PARTNUM_CP2108	0x08
376 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
377 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
378 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
379 #define CP210X_PARTNUM_UNKNOWN	0xFF
380 
381 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
382 struct cp210x_comm_status {
383 	__le32   ulErrors;
384 	__le32   ulHoldReasons;
385 	__le32   ulAmountInInQueue;
386 	__le32   ulAmountInOutQueue;
387 	u8       bEofReceived;
388 	u8       bWaitForImmediate;
389 	u8       bReserved;
390 } __packed;
391 
392 /*
393  * CP210X_PURGE - 16 bits passed in wValue of USB request.
394  * SiLabs app note AN571 gives a strange description of the 4 bits:
395  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
396  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
397  */
398 #define PURGE_ALL		0x000f
399 
400 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
401 struct cp210x_flow_ctl {
402 	__le32	ulControlHandshake;
403 	__le32	ulFlowReplace;
404 	__le32	ulXonLimit;
405 	__le32	ulXoffLimit;
406 } __packed;
407 
408 /* cp210x_flow_ctl::ulControlHandshake */
409 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
410 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
411 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
412 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
413 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
414 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
415 
416 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
417 #define CP210X_SERIAL_DTR_INACTIVE	0
418 #define CP210X_SERIAL_DTR_ACTIVE	1
419 #define CP210X_SERIAL_DTR_FLOW_CTL	2
420 
421 /* cp210x_flow_ctl::ulFlowReplace */
422 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
423 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
424 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
425 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
426 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
427 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
428 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
429 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
430 
431 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
432 #define CP210X_SERIAL_RTS_INACTIVE	0
433 #define CP210X_SERIAL_RTS_ACTIVE	1
434 #define CP210X_SERIAL_RTS_FLOW_CTL	2
435 
436 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
437 struct cp210x_pin_mode {
438 	u8	eci;
439 	u8	sci;
440 } __packed;
441 
442 #define CP210X_PIN_MODE_MODEM		0
443 #define CP210X_PIN_MODE_GPIO		BIT(0)
444 
445 /*
446  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes.
447  * Structure needs padding due to unused/unspecified bytes.
448  */
449 struct cp210x_config {
450 	__le16	gpio_mode;
451 	u8	__pad0[2];
452 	__le16	reset_state;
453 	u8	__pad1[4];
454 	__le16	suspend_state;
455 	u8	sci_cfg;
456 	u8	eci_cfg;
457 	u8	device_cfg;
458 } __packed;
459 
460 /* GPIO modes */
461 #define CP210X_SCI_GPIO_MODE_OFFSET	9
462 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
463 
464 #define CP210X_ECI_GPIO_MODE_OFFSET	2
465 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
466 
467 /* CP2105 port configuration values */
468 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
469 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
470 #define CP2105_GPIO1_RS485_MODE		BIT(2)
471 
472 /* CP2102N configuration array indices */
473 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
474 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
475 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
476 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
477 
478 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
479 struct cp210x_gpio_write {
480 	u8	mask;
481 	u8	state;
482 } __packed;
483 
484 /*
485  * Helper to get interface number when we only have struct usb_serial.
486  */
487 static u8 cp210x_interface_num(struct usb_serial *serial)
488 {
489 	struct usb_host_interface *cur_altsetting;
490 
491 	cur_altsetting = serial->interface->cur_altsetting;
492 
493 	return cur_altsetting->desc.bInterfaceNumber;
494 }
495 
496 /*
497  * Reads a variable-sized block of CP210X_ registers, identified by req.
498  * Returns data into buf in native USB byte order.
499  */
500 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
501 		void *buf, int bufsize)
502 {
503 	struct usb_serial *serial = port->serial;
504 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
505 	void *dmabuf;
506 	int result;
507 
508 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
509 	if (!dmabuf) {
510 		/*
511 		 * FIXME Some callers don't bother to check for error,
512 		 * at least give them consistent junk until they are fixed
513 		 */
514 		memset(buf, 0, bufsize);
515 		return -ENOMEM;
516 	}
517 
518 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
519 			req, REQTYPE_INTERFACE_TO_HOST, 0,
520 			port_priv->bInterfaceNumber, dmabuf, bufsize,
521 			USB_CTRL_SET_TIMEOUT);
522 	if (result == bufsize) {
523 		memcpy(buf, dmabuf, bufsize);
524 		result = 0;
525 	} else {
526 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
527 				req, bufsize, result);
528 		if (result >= 0)
529 			result = -EIO;
530 
531 		/*
532 		 * FIXME Some callers don't bother to check for error,
533 		 * at least give them consistent junk until they are fixed
534 		 */
535 		memset(buf, 0, bufsize);
536 	}
537 
538 	kfree(dmabuf);
539 
540 	return result;
541 }
542 
543 /*
544  * Reads any 32-bit CP210X_ register identified by req.
545  */
546 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
547 {
548 	__le32 le32_val;
549 	int err;
550 
551 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
552 	if (err) {
553 		/*
554 		 * FIXME Some callers don't bother to check for error,
555 		 * at least give them consistent junk until they are fixed
556 		 */
557 		*val = 0;
558 		return err;
559 	}
560 
561 	*val = le32_to_cpu(le32_val);
562 
563 	return 0;
564 }
565 
566 /*
567  * Reads any 16-bit CP210X_ register identified by req.
568  */
569 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
570 {
571 	__le16 le16_val;
572 	int err;
573 
574 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
575 	if (err)
576 		return err;
577 
578 	*val = le16_to_cpu(le16_val);
579 
580 	return 0;
581 }
582 
583 /*
584  * Reads any 8-bit CP210X_ register identified by req.
585  */
586 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
587 {
588 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
589 }
590 
591 /*
592  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
593  * Returns data into buf in native USB byte order.
594  */
595 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
596 				    void *buf, int bufsize)
597 {
598 	void *dmabuf;
599 	int result;
600 
601 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
602 	if (!dmabuf)
603 		return -ENOMEM;
604 
605 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
606 				 CP210X_VENDOR_SPECIFIC, type, val,
607 				 cp210x_interface_num(serial), dmabuf, bufsize,
608 				 USB_CTRL_GET_TIMEOUT);
609 	if (result == bufsize) {
610 		memcpy(buf, dmabuf, bufsize);
611 		result = 0;
612 	} else {
613 		dev_err(&serial->interface->dev,
614 			"failed to get vendor val 0x%04x size %d: %d\n", val,
615 			bufsize, result);
616 		if (result >= 0)
617 			result = -EIO;
618 	}
619 
620 	kfree(dmabuf);
621 
622 	return result;
623 }
624 
625 /*
626  * Writes any 16-bit CP210X_ register (req) whose value is passed
627  * entirely in the wValue field of the USB request.
628  */
629 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
630 {
631 	struct usb_serial *serial = port->serial;
632 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
633 	int result;
634 
635 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
636 			req, REQTYPE_HOST_TO_INTERFACE, val,
637 			port_priv->bInterfaceNumber, NULL, 0,
638 			USB_CTRL_SET_TIMEOUT);
639 	if (result < 0) {
640 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
641 				req, result);
642 	}
643 
644 	return result;
645 }
646 
647 /*
648  * Writes a variable-sized block of CP210X_ registers, identified by req.
649  * Data in buf must be in native USB byte order.
650  */
651 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
652 		void *buf, int bufsize)
653 {
654 	struct usb_serial *serial = port->serial;
655 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
656 	void *dmabuf;
657 	int result;
658 
659 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
660 	if (!dmabuf)
661 		return -ENOMEM;
662 
663 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
664 			req, REQTYPE_HOST_TO_INTERFACE, 0,
665 			port_priv->bInterfaceNumber, dmabuf, bufsize,
666 			USB_CTRL_SET_TIMEOUT);
667 
668 	kfree(dmabuf);
669 
670 	if (result == bufsize) {
671 		result = 0;
672 	} else {
673 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
674 				req, bufsize, result);
675 		if (result >= 0)
676 			result = -EIO;
677 	}
678 
679 	return result;
680 }
681 
682 /*
683  * Writes any 32-bit CP210X_ register identified by req.
684  */
685 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
686 {
687 	__le32 le32_val;
688 
689 	le32_val = cpu_to_le32(val);
690 
691 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
692 }
693 
694 #ifdef CONFIG_GPIOLIB
695 /*
696  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
697  * Data in buf must be in native USB byte order.
698  */
699 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
700 				     u16 val, void *buf, int bufsize)
701 {
702 	void *dmabuf;
703 	int result;
704 
705 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
706 	if (!dmabuf)
707 		return -ENOMEM;
708 
709 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
710 				 CP210X_VENDOR_SPECIFIC, type, val,
711 				 cp210x_interface_num(serial), dmabuf, bufsize,
712 				 USB_CTRL_SET_TIMEOUT);
713 
714 	kfree(dmabuf);
715 
716 	if (result == bufsize) {
717 		result = 0;
718 	} else {
719 		dev_err(&serial->interface->dev,
720 			"failed to set vendor val 0x%04x size %d: %d\n", val,
721 			bufsize, result);
722 		if (result >= 0)
723 			result = -EIO;
724 	}
725 
726 	return result;
727 }
728 #endif
729 
730 /*
731  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
732  * Write a known good value 0x800, read it back.
733  * If it comes back swapped the bug is detected.
734  * Preserve the original register value.
735  */
736 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
737 {
738 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
739 	u16 line_ctl_save;
740 	u16 line_ctl_test;
741 	int err;
742 
743 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
744 	if (err)
745 		return err;
746 
747 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
748 	if (err)
749 		return err;
750 
751 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
752 	if (err)
753 		return err;
754 
755 	if (line_ctl_test == 8) {
756 		port_priv->has_swapped_line_ctl = true;
757 		line_ctl_save = swab16(line_ctl_save);
758 	}
759 
760 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
761 }
762 
763 /*
764  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
765  * to workaround cp2108 bug and get correct value.
766  */
767 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
768 {
769 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
770 	int err;
771 
772 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
773 	if (err)
774 		return err;
775 
776 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
777 	if (port_priv->has_swapped_line_ctl)
778 		*ctl = swab16(*ctl);
779 
780 	return 0;
781 }
782 
783 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
784 {
785 	int result;
786 
787 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
788 	if (result) {
789 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
790 		return result;
791 	}
792 
793 	/* Configure the termios structure */
794 	cp210x_get_termios(tty, port);
795 
796 	/* The baud rate must be initialised on cp2104 */
797 	if (tty)
798 		cp210x_change_speed(tty, port, NULL);
799 
800 	return usb_serial_generic_open(tty, port);
801 }
802 
803 static void cp210x_close(struct usb_serial_port *port)
804 {
805 	usb_serial_generic_close(port);
806 
807 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
808 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
809 
810 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
811 }
812 
813 /*
814  * Read how many bytes are waiting in the TX queue.
815  */
816 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
817 		u32 *count)
818 {
819 	struct usb_serial *serial = port->serial;
820 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
821 	struct cp210x_comm_status *sts;
822 	int result;
823 
824 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
825 	if (!sts)
826 		return -ENOMEM;
827 
828 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
829 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
830 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
831 			USB_CTRL_GET_TIMEOUT);
832 	if (result == sizeof(*sts)) {
833 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
834 		result = 0;
835 	} else {
836 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
837 		if (result >= 0)
838 			result = -EIO;
839 	}
840 
841 	kfree(sts);
842 
843 	return result;
844 }
845 
846 static bool cp210x_tx_empty(struct usb_serial_port *port)
847 {
848 	int err;
849 	u32 count;
850 
851 	err = cp210x_get_tx_queue_byte_count(port, &count);
852 	if (err)
853 		return true;
854 
855 	return !count;
856 }
857 
858 /*
859  * cp210x_get_termios
860  * Reads the baud rate, data bits, parity, stop bits and flow control mode
861  * from the device, corrects any unsupported values, and configures the
862  * termios structure to reflect the state of the device
863  */
864 static void cp210x_get_termios(struct tty_struct *tty,
865 	struct usb_serial_port *port)
866 {
867 	unsigned int baud;
868 
869 	if (tty) {
870 		cp210x_get_termios_port(tty->driver_data,
871 			&tty->termios.c_cflag, &baud);
872 		tty_encode_baud_rate(tty, baud, baud);
873 	} else {
874 		tcflag_t cflag;
875 		cflag = 0;
876 		cp210x_get_termios_port(port, &cflag, &baud);
877 	}
878 }
879 
880 /*
881  * cp210x_get_termios_port
882  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
883  */
884 static void cp210x_get_termios_port(struct usb_serial_port *port,
885 	tcflag_t *cflagp, unsigned int *baudp)
886 {
887 	struct device *dev = &port->dev;
888 	tcflag_t cflag;
889 	struct cp210x_flow_ctl flow_ctl;
890 	u32 baud;
891 	u16 bits;
892 	u32 ctl_hs;
893 
894 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
895 
896 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
897 	*baudp = baud;
898 
899 	cflag = *cflagp;
900 
901 	cp210x_get_line_ctl(port, &bits);
902 	cflag &= ~CSIZE;
903 	switch (bits & BITS_DATA_MASK) {
904 	case BITS_DATA_5:
905 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
906 		cflag |= CS5;
907 		break;
908 	case BITS_DATA_6:
909 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
910 		cflag |= CS6;
911 		break;
912 	case BITS_DATA_7:
913 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
914 		cflag |= CS7;
915 		break;
916 	case BITS_DATA_8:
917 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
918 		cflag |= CS8;
919 		break;
920 	case BITS_DATA_9:
921 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
922 		cflag |= CS8;
923 		bits &= ~BITS_DATA_MASK;
924 		bits |= BITS_DATA_8;
925 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
926 		break;
927 	default:
928 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
929 		cflag |= CS8;
930 		bits &= ~BITS_DATA_MASK;
931 		bits |= BITS_DATA_8;
932 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
933 		break;
934 	}
935 
936 	switch (bits & BITS_PARITY_MASK) {
937 	case BITS_PARITY_NONE:
938 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
939 		cflag &= ~PARENB;
940 		break;
941 	case BITS_PARITY_ODD:
942 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
943 		cflag |= (PARENB|PARODD);
944 		break;
945 	case BITS_PARITY_EVEN:
946 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
947 		cflag &= ~PARODD;
948 		cflag |= PARENB;
949 		break;
950 	case BITS_PARITY_MARK:
951 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
952 		cflag |= (PARENB|PARODD|CMSPAR);
953 		break;
954 	case BITS_PARITY_SPACE:
955 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
956 		cflag &= ~PARODD;
957 		cflag |= (PARENB|CMSPAR);
958 		break;
959 	default:
960 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
961 		cflag &= ~PARENB;
962 		bits &= ~BITS_PARITY_MASK;
963 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
964 		break;
965 	}
966 
967 	cflag &= ~CSTOPB;
968 	switch (bits & BITS_STOP_MASK) {
969 	case BITS_STOP_1:
970 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
971 		break;
972 	case BITS_STOP_1_5:
973 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
974 		bits &= ~BITS_STOP_MASK;
975 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
976 		break;
977 	case BITS_STOP_2:
978 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
979 		cflag |= CSTOPB;
980 		break;
981 	default:
982 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
983 		bits &= ~BITS_STOP_MASK;
984 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
985 		break;
986 	}
987 
988 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
989 			sizeof(flow_ctl));
990 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
991 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
992 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
993 		cflag |= CRTSCTS;
994 	} else {
995 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
996 		cflag &= ~CRTSCTS;
997 	}
998 
999 	*cflagp = cflag;
1000 }
1001 
1002 struct cp210x_rate {
1003 	speed_t rate;
1004 	speed_t high;
1005 };
1006 
1007 static const struct cp210x_rate cp210x_an205_table1[] = {
1008 	{ 300, 300 },
1009 	{ 600, 600 },
1010 	{ 1200, 1200 },
1011 	{ 1800, 1800 },
1012 	{ 2400, 2400 },
1013 	{ 4000, 4000 },
1014 	{ 4800, 4803 },
1015 	{ 7200, 7207 },
1016 	{ 9600, 9612 },
1017 	{ 14400, 14428 },
1018 	{ 16000, 16062 },
1019 	{ 19200, 19250 },
1020 	{ 28800, 28912 },
1021 	{ 38400, 38601 },
1022 	{ 51200, 51558 },
1023 	{ 56000, 56280 },
1024 	{ 57600, 58053 },
1025 	{ 64000, 64111 },
1026 	{ 76800, 77608 },
1027 	{ 115200, 117028 },
1028 	{ 128000, 129347 },
1029 	{ 153600, 156868 },
1030 	{ 230400, 237832 },
1031 	{ 250000, 254234 },
1032 	{ 256000, 273066 },
1033 	{ 460800, 491520 },
1034 	{ 500000, 567138 },
1035 	{ 576000, 670254 },
1036 	{ 921600, UINT_MAX }
1037 };
1038 
1039 /*
1040  * Quantises the baud rate as per AN205 Table 1
1041  */
1042 static speed_t cp210x_get_an205_rate(speed_t baud)
1043 {
1044 	int i;
1045 
1046 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1047 		if (baud <= cp210x_an205_table1[i].high)
1048 			break;
1049 	}
1050 
1051 	return cp210x_an205_table1[i].rate;
1052 }
1053 
1054 static speed_t cp210x_get_actual_rate(struct usb_serial *serial, speed_t baud)
1055 {
1056 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1057 	unsigned int prescale = 1;
1058 	unsigned int div;
1059 
1060 	baud = clamp(baud, 300u, priv->max_speed);
1061 
1062 	if (baud <= 365)
1063 		prescale = 4;
1064 
1065 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1066 	baud = 48000000 / (2 * prescale * div);
1067 
1068 	return baud;
1069 }
1070 
1071 /*
1072  * CP2101 supports the following baud rates:
1073  *
1074  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1075  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1076  *
1077  * CP2102 and CP2103 support the following additional rates:
1078  *
1079  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1080  *	576000
1081  *
1082  * The device will map a requested rate to a supported one, but the result
1083  * of requests for rates greater than 1053257 is undefined (see AN205).
1084  *
1085  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1086  * respectively, with an error less than 1%. The actual rates are determined
1087  * by
1088  *
1089  *	div = round(freq / (2 x prescale x request))
1090  *	actual = freq / (2 x prescale x div)
1091  *
1092  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1093  * or 1 otherwise.
1094  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1095  * otherwise.
1096  */
1097 static void cp210x_change_speed(struct tty_struct *tty,
1098 		struct usb_serial_port *port, struct ktermios *old_termios)
1099 {
1100 	struct usb_serial *serial = port->serial;
1101 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1102 	u32 baud;
1103 
1104 	baud = tty->termios.c_ospeed;
1105 
1106 	/*
1107 	 * This maps the requested rate to the actual rate, a valid rate on
1108 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1109 	 *
1110 	 * NOTE: B0 is not implemented.
1111 	 */
1112 	if (priv->use_actual_rate)
1113 		baud = cp210x_get_actual_rate(serial, baud);
1114 	else if (baud < 1000000)
1115 		baud = cp210x_get_an205_rate(baud);
1116 	else if (baud > priv->max_speed)
1117 		baud = priv->max_speed;
1118 
1119 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1120 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1121 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1122 		if (old_termios)
1123 			baud = old_termios->c_ospeed;
1124 		else
1125 			baud = 9600;
1126 	}
1127 
1128 	tty_encode_baud_rate(tty, baud, baud);
1129 }
1130 
1131 static void cp210x_set_termios(struct tty_struct *tty,
1132 		struct usb_serial_port *port, struct ktermios *old_termios)
1133 {
1134 	struct device *dev = &port->dev;
1135 	unsigned int cflag, old_cflag;
1136 	u16 bits;
1137 
1138 	cflag = tty->termios.c_cflag;
1139 	old_cflag = old_termios->c_cflag;
1140 
1141 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1142 		cp210x_change_speed(tty, port, old_termios);
1143 
1144 	/* If the number of data bits is to be updated */
1145 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1146 		cp210x_get_line_ctl(port, &bits);
1147 		bits &= ~BITS_DATA_MASK;
1148 		switch (cflag & CSIZE) {
1149 		case CS5:
1150 			bits |= BITS_DATA_5;
1151 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1152 			break;
1153 		case CS6:
1154 			bits |= BITS_DATA_6;
1155 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1156 			break;
1157 		case CS7:
1158 			bits |= BITS_DATA_7;
1159 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1160 			break;
1161 		case CS8:
1162 		default:
1163 			bits |= BITS_DATA_8;
1164 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1165 			break;
1166 		}
1167 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1168 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1169 	}
1170 
1171 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1172 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1173 		cp210x_get_line_ctl(port, &bits);
1174 		bits &= ~BITS_PARITY_MASK;
1175 		if (cflag & PARENB) {
1176 			if (cflag & CMSPAR) {
1177 				if (cflag & PARODD) {
1178 					bits |= BITS_PARITY_MARK;
1179 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1180 				} else {
1181 					bits |= BITS_PARITY_SPACE;
1182 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1183 				}
1184 			} else {
1185 				if (cflag & PARODD) {
1186 					bits |= BITS_PARITY_ODD;
1187 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1188 				} else {
1189 					bits |= BITS_PARITY_EVEN;
1190 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1191 				}
1192 			}
1193 		}
1194 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1195 			dev_dbg(dev, "Parity mode not supported by device\n");
1196 	}
1197 
1198 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1199 		cp210x_get_line_ctl(port, &bits);
1200 		bits &= ~BITS_STOP_MASK;
1201 		if (cflag & CSTOPB) {
1202 			bits |= BITS_STOP_2;
1203 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1204 		} else {
1205 			bits |= BITS_STOP_1;
1206 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1207 		}
1208 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1209 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1210 	}
1211 
1212 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1213 		struct cp210x_flow_ctl flow_ctl;
1214 		u32 ctl_hs;
1215 		u32 flow_repl;
1216 
1217 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1218 				sizeof(flow_ctl));
1219 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1220 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1221 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1222 				__func__, ctl_hs, flow_repl);
1223 
1224 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1225 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1226 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1227 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1228 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1229 		if (cflag & CRTSCTS) {
1230 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1231 
1232 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1233 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1234 					CP210X_SERIAL_RTS_FLOW_CTL);
1235 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1236 		} else {
1237 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1238 
1239 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1240 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1241 					CP210X_SERIAL_RTS_ACTIVE);
1242 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1243 		}
1244 
1245 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1246 				__func__, ctl_hs, flow_repl);
1247 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1248 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1249 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1250 				sizeof(flow_ctl));
1251 	}
1252 
1253 }
1254 
1255 static int cp210x_tiocmset(struct tty_struct *tty,
1256 		unsigned int set, unsigned int clear)
1257 {
1258 	struct usb_serial_port *port = tty->driver_data;
1259 	return cp210x_tiocmset_port(port, set, clear);
1260 }
1261 
1262 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1263 		unsigned int set, unsigned int clear)
1264 {
1265 	u16 control = 0;
1266 
1267 	if (set & TIOCM_RTS) {
1268 		control |= CONTROL_RTS;
1269 		control |= CONTROL_WRITE_RTS;
1270 	}
1271 	if (set & TIOCM_DTR) {
1272 		control |= CONTROL_DTR;
1273 		control |= CONTROL_WRITE_DTR;
1274 	}
1275 	if (clear & TIOCM_RTS) {
1276 		control &= ~CONTROL_RTS;
1277 		control |= CONTROL_WRITE_RTS;
1278 	}
1279 	if (clear & TIOCM_DTR) {
1280 		control &= ~CONTROL_DTR;
1281 		control |= CONTROL_WRITE_DTR;
1282 	}
1283 
1284 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1285 
1286 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1287 }
1288 
1289 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1290 {
1291 	if (on)
1292 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1293 	else
1294 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1295 }
1296 
1297 static int cp210x_tiocmget(struct tty_struct *tty)
1298 {
1299 	struct usb_serial_port *port = tty->driver_data;
1300 	u8 control;
1301 	int result;
1302 
1303 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1304 	if (result)
1305 		return result;
1306 
1307 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1308 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1309 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1310 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1311 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1312 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1313 
1314 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1315 
1316 	return result;
1317 }
1318 
1319 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1320 {
1321 	struct usb_serial_port *port = tty->driver_data;
1322 	u16 state;
1323 
1324 	if (break_state == 0)
1325 		state = BREAK_OFF;
1326 	else
1327 		state = BREAK_ON;
1328 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1329 		state == BREAK_OFF ? "off" : "on");
1330 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1331 }
1332 
1333 #ifdef CONFIG_GPIOLIB
1334 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1335 {
1336 	struct usb_serial *serial = gpiochip_get_data(gc);
1337 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1338 
1339 	if (priv->gpio_altfunc & BIT(offset))
1340 		return -ENODEV;
1341 
1342 	return 0;
1343 }
1344 
1345 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1346 {
1347 	struct usb_serial *serial = gpiochip_get_data(gc);
1348 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1349 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1350 	int result;
1351 	u8 buf;
1352 
1353 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1354 		req_type = REQTYPE_INTERFACE_TO_HOST;
1355 
1356 	result = cp210x_read_vendor_block(serial, req_type,
1357 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1358 	if (result < 0)
1359 		return result;
1360 
1361 	return !!(buf & BIT(gpio));
1362 }
1363 
1364 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1365 {
1366 	struct usb_serial *serial = gpiochip_get_data(gc);
1367 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1368 	struct cp210x_gpio_write buf;
1369 	int result;
1370 
1371 	if (value == 1)
1372 		buf.state = BIT(gpio);
1373 	else
1374 		buf.state = 0;
1375 
1376 	buf.mask = BIT(gpio);
1377 
1378 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1379 		result = cp210x_write_vendor_block(serial,
1380 						   REQTYPE_HOST_TO_INTERFACE,
1381 						   CP210X_WRITE_LATCH, &buf,
1382 						   sizeof(buf));
1383 	} else {
1384 		u16 wIndex = buf.state << 8 | buf.mask;
1385 
1386 		result = usb_control_msg(serial->dev,
1387 					 usb_sndctrlpipe(serial->dev, 0),
1388 					 CP210X_VENDOR_SPECIFIC,
1389 					 REQTYPE_HOST_TO_DEVICE,
1390 					 CP210X_WRITE_LATCH,
1391 					 wIndex,
1392 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1393 	}
1394 
1395 	if (result < 0) {
1396 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1397 				result);
1398 	}
1399 }
1400 
1401 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1402 {
1403 	struct usb_serial *serial = gpiochip_get_data(gc);
1404 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1405 
1406 	return priv->gpio_input & BIT(gpio);
1407 }
1408 
1409 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1410 {
1411 	struct usb_serial *serial = gpiochip_get_data(gc);
1412 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1413 
1414 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1415 		/* hardware does not support an input mode */
1416 		return -ENOTSUPP;
1417 	}
1418 
1419 	/* push-pull pins cannot be changed to be inputs */
1420 	if (priv->gpio_pushpull & BIT(gpio))
1421 		return -EINVAL;
1422 
1423 	/* make sure to release pin if it is being driven low */
1424 	cp210x_gpio_set(gc, gpio, 1);
1425 
1426 	priv->gpio_input |= BIT(gpio);
1427 
1428 	return 0;
1429 }
1430 
1431 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1432 					int value)
1433 {
1434 	struct usb_serial *serial = gpiochip_get_data(gc);
1435 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1436 
1437 	priv->gpio_input &= ~BIT(gpio);
1438 	cp210x_gpio_set(gc, gpio, value);
1439 
1440 	return 0;
1441 }
1442 
1443 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1444 				  unsigned long config)
1445 {
1446 	struct usb_serial *serial = gpiochip_get_data(gc);
1447 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1448 	enum pin_config_param param = pinconf_to_config_param(config);
1449 
1450 	/* Succeed only if in correct mode (this can't be set at runtime) */
1451 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1452 	    (priv->gpio_pushpull & BIT(gpio)))
1453 		return 0;
1454 
1455 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1456 	    !(priv->gpio_pushpull & BIT(gpio)))
1457 		return 0;
1458 
1459 	return -ENOTSUPP;
1460 }
1461 
1462 /*
1463  * This function is for configuring GPIO using shared pins, where other signals
1464  * are made unavailable by configuring the use of GPIO. This is believed to be
1465  * only applicable to the cp2105 at this point, the other devices supported by
1466  * this driver that provide GPIO do so in a way that does not impact other
1467  * signals and are thus expected to have very different initialisation.
1468  */
1469 static int cp2105_gpioconf_init(struct usb_serial *serial)
1470 {
1471 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1472 	struct cp210x_pin_mode mode;
1473 	struct cp210x_config config;
1474 	u8 intf_num = cp210x_interface_num(serial);
1475 	u8 iface_config;
1476 	int result;
1477 
1478 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1479 					  CP210X_GET_DEVICEMODE, &mode,
1480 					  sizeof(mode));
1481 	if (result < 0)
1482 		return result;
1483 
1484 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1485 					  CP210X_GET_PORTCONFIG, &config,
1486 					  sizeof(config));
1487 	if (result < 0)
1488 		return result;
1489 
1490 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1491 	if (intf_num == 0) {
1492 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1493 			/* mark all GPIOs of this interface as reserved */
1494 			priv->gpio_altfunc = 0xff;
1495 			return 0;
1496 		}
1497 
1498 		iface_config = config.eci_cfg;
1499 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1500 						CP210X_ECI_GPIO_MODE_MASK) >>
1501 						CP210X_ECI_GPIO_MODE_OFFSET);
1502 		priv->gc.ngpio = 2;
1503 	} else if (intf_num == 1) {
1504 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1505 			/* mark all GPIOs of this interface as reserved */
1506 			priv->gpio_altfunc = 0xff;
1507 			return 0;
1508 		}
1509 
1510 		iface_config = config.sci_cfg;
1511 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1512 						CP210X_SCI_GPIO_MODE_MASK) >>
1513 						CP210X_SCI_GPIO_MODE_OFFSET);
1514 		priv->gc.ngpio = 3;
1515 	} else {
1516 		return -ENODEV;
1517 	}
1518 
1519 	/* mark all pins which are not in GPIO mode */
1520 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1521 		priv->gpio_altfunc |= BIT(0);
1522 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1523 			CP2105_GPIO1_RS485_MODE))
1524 		priv->gpio_altfunc |= BIT(1);
1525 
1526 	/* driver implementation for CP2105 only supports outputs */
1527 	priv->gpio_input = 0;
1528 
1529 	return 0;
1530 }
1531 
1532 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1533 {
1534 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1535 	const u16 config_size = 0x02a6;
1536 	u8 gpio_rst_latch;
1537 	u8 config_version;
1538 	u8 gpio_pushpull;
1539 	u8 *config_buf;
1540 	u8 gpio_latch;
1541 	u8 gpio_ctrl;
1542 	int result;
1543 	u8 i;
1544 
1545 	/*
1546 	 * Retrieve device configuration from the device.
1547 	 * The array received contains all customization settings done at the
1548 	 * factory/manufacturer. Format of the array is documented at the
1549 	 * time of writing at:
1550 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1551 	 */
1552 	config_buf = kmalloc(config_size, GFP_KERNEL);
1553 	if (!config_buf)
1554 		return -ENOMEM;
1555 
1556 	result = cp210x_read_vendor_block(serial,
1557 					  REQTYPE_DEVICE_TO_HOST,
1558 					  CP210X_READ_2NCONFIG,
1559 					  config_buf,
1560 					  config_size);
1561 	if (result < 0) {
1562 		kfree(config_buf);
1563 		return result;
1564 	}
1565 
1566 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1567 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1568 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1569 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1570 
1571 	kfree(config_buf);
1572 
1573 	/* Make sure this is a config format we understand. */
1574 	if (config_version != 0x01)
1575 		return -ENOTSUPP;
1576 
1577 	/*
1578 	 * We only support 4 GPIOs even on the QFN28 package, because
1579 	 * config locations of GPIOs 4-6 determined using reverse
1580 	 * engineering revealed conflicting offsets with other
1581 	 * documented functions. So we'll just play it safe for now.
1582 	 */
1583 	priv->gc.ngpio = 4;
1584 
1585 	/*
1586 	 * Get default pin states after reset. Needed so we can determine
1587 	 * the direction of an open-drain pin.
1588 	 */
1589 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1590 
1591 	/* 0 indicates open-drain mode, 1 is push-pull */
1592 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1593 
1594 	/* 0 indicates GPIO mode, 1 is alternate function */
1595 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1596 
1597 	/*
1598 	 * The CP2102N does not strictly has input and output pin modes,
1599 	 * it only knows open-drain and push-pull modes which is set at
1600 	 * factory. An open-drain pin can function both as an
1601 	 * input or an output. We emulate input mode for open-drain pins
1602 	 * by making sure they are not driven low, and we do not allow
1603 	 * push-pull pins to be set as an input.
1604 	 */
1605 	for (i = 0; i < priv->gc.ngpio; ++i) {
1606 		/*
1607 		 * Set direction to "input" iff pin is open-drain and reset
1608 		 * value is 1.
1609 		 */
1610 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1611 			priv->gpio_input |= BIT(i);
1612 	}
1613 
1614 	return 0;
1615 }
1616 
1617 static int cp210x_gpio_init(struct usb_serial *serial)
1618 {
1619 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1620 	int result;
1621 
1622 	switch (priv->partnum) {
1623 	case CP210X_PARTNUM_CP2105:
1624 		result = cp2105_gpioconf_init(serial);
1625 		break;
1626 	case CP210X_PARTNUM_CP2102N_QFN28:
1627 	case CP210X_PARTNUM_CP2102N_QFN24:
1628 	case CP210X_PARTNUM_CP2102N_QFN20:
1629 		result = cp2102n_gpioconf_init(serial);
1630 		break;
1631 	default:
1632 		return 0;
1633 	}
1634 
1635 	if (result < 0)
1636 		return result;
1637 
1638 	priv->gc.label = "cp210x";
1639 	priv->gc.request = cp210x_gpio_request;
1640 	priv->gc.get_direction = cp210x_gpio_direction_get;
1641 	priv->gc.direction_input = cp210x_gpio_direction_input;
1642 	priv->gc.direction_output = cp210x_gpio_direction_output;
1643 	priv->gc.get = cp210x_gpio_get;
1644 	priv->gc.set = cp210x_gpio_set;
1645 	priv->gc.set_config = cp210x_gpio_set_config;
1646 	priv->gc.owner = THIS_MODULE;
1647 	priv->gc.parent = &serial->interface->dev;
1648 	priv->gc.base = -1;
1649 	priv->gc.can_sleep = true;
1650 
1651 	result = gpiochip_add_data(&priv->gc, serial);
1652 	if (!result)
1653 		priv->gpio_registered = true;
1654 
1655 	return result;
1656 }
1657 
1658 static void cp210x_gpio_remove(struct usb_serial *serial)
1659 {
1660 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1661 
1662 	if (priv->gpio_registered) {
1663 		gpiochip_remove(&priv->gc);
1664 		priv->gpio_registered = false;
1665 	}
1666 }
1667 
1668 #else
1669 
1670 static int cp210x_gpio_init(struct usb_serial *serial)
1671 {
1672 	return 0;
1673 }
1674 
1675 static void cp210x_gpio_remove(struct usb_serial *serial)
1676 {
1677 	/* Nothing to do */
1678 }
1679 
1680 #endif
1681 
1682 static int cp210x_port_probe(struct usb_serial_port *port)
1683 {
1684 	struct usb_serial *serial = port->serial;
1685 	struct cp210x_port_private *port_priv;
1686 	int ret;
1687 
1688 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1689 	if (!port_priv)
1690 		return -ENOMEM;
1691 
1692 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1693 
1694 	usb_set_serial_port_data(port, port_priv);
1695 
1696 	ret = cp210x_detect_swapped_line_ctl(port);
1697 	if (ret) {
1698 		kfree(port_priv);
1699 		return ret;
1700 	}
1701 
1702 	return 0;
1703 }
1704 
1705 static int cp210x_port_remove(struct usb_serial_port *port)
1706 {
1707 	struct cp210x_port_private *port_priv;
1708 
1709 	port_priv = usb_get_serial_port_data(port);
1710 	kfree(port_priv);
1711 
1712 	return 0;
1713 }
1714 
1715 static void cp210x_init_max_speed(struct usb_serial *serial)
1716 {
1717 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1718 	bool use_actual_rate = false;
1719 	speed_t max;
1720 
1721 	switch (priv->partnum) {
1722 	case CP210X_PARTNUM_CP2101:
1723 		max = 921600;
1724 		break;
1725 	case CP210X_PARTNUM_CP2102:
1726 	case CP210X_PARTNUM_CP2103:
1727 		max = 1000000;
1728 		break;
1729 	case CP210X_PARTNUM_CP2104:
1730 		use_actual_rate = true;
1731 		max = 2000000;
1732 		break;
1733 	case CP210X_PARTNUM_CP2108:
1734 		max = 2000000;
1735 		break;
1736 	case CP210X_PARTNUM_CP2105:
1737 		if (cp210x_interface_num(serial) == 0) {
1738 			use_actual_rate = true;
1739 			max = 2000000;	/* ECI */
1740 		} else {
1741 			max = 921600;	/* SCI */
1742 		}
1743 		break;
1744 	case CP210X_PARTNUM_CP2102N_QFN28:
1745 	case CP210X_PARTNUM_CP2102N_QFN24:
1746 	case CP210X_PARTNUM_CP2102N_QFN20:
1747 		use_actual_rate = true;
1748 		max = 3000000;
1749 		break;
1750 	default:
1751 		max = 2000000;
1752 		break;
1753 	}
1754 
1755 	priv->max_speed = max;
1756 	priv->use_actual_rate = use_actual_rate;
1757 }
1758 
1759 static int cp210x_attach(struct usb_serial *serial)
1760 {
1761 	int result;
1762 	struct cp210x_serial_private *priv;
1763 
1764 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1765 	if (!priv)
1766 		return -ENOMEM;
1767 
1768 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1769 					  CP210X_GET_PARTNUM, &priv->partnum,
1770 					  sizeof(priv->partnum));
1771 	if (result < 0) {
1772 		dev_warn(&serial->interface->dev,
1773 			 "querying part number failed\n");
1774 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1775 	}
1776 
1777 	usb_set_serial_data(serial, priv);
1778 
1779 	cp210x_init_max_speed(serial);
1780 
1781 	result = cp210x_gpio_init(serial);
1782 	if (result < 0) {
1783 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1784 				result);
1785 	}
1786 
1787 	return 0;
1788 }
1789 
1790 static void cp210x_disconnect(struct usb_serial *serial)
1791 {
1792 	cp210x_gpio_remove(serial);
1793 }
1794 
1795 static void cp210x_release(struct usb_serial *serial)
1796 {
1797 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1798 
1799 	cp210x_gpio_remove(serial);
1800 
1801 	kfree(priv);
1802 }
1803 
1804 module_usb_serial_driver(serial_drivers, id_table);
1805 
1806 MODULE_DESCRIPTION(DRIVER_DESC);
1807 MODULE_LICENSE("GPL v2");
1808