xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision be709d48)
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(0x0B00, 0x3070) }, /* Ingenico 3070 */
65 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
66 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
67 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
68 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
69 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
70 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
71 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
72 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
73 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
74 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
75 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
76 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
77 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
78 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
79 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
80 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
81 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
82 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
83 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
84 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
85 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
86 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
87 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
88 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
89 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
90 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
91 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
92 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
93 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
94 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
95 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
96 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
97 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
98 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
99 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
100 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
103 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
104 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
105 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
106 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
107 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
108 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
109 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
110 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
111 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
112 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
113 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
114 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
115 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
116 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
117 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
118 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
119 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
120 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
121 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
122 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
123 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
124 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
125 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
126 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
127 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
128 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
129 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
130 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
131 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
132 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
133 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
134 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
135 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
136 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
137 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
138 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
139 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
140 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
141 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
142 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
143 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
144 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
145 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
146 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
147 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
148 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
149 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
150 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
151 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
152 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
153 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
154 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
155 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
156 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
157 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
158 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
159 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
160 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
161 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
162 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
163 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
164 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
165 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
166 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
167 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
168 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
169 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
170 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
171 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
172 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
173 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
174 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
175 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
176 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
177 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
178 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
179 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
180 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
181 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
182 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
183 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
184 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
185 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
186 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
187 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
188 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
189 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
190 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
191 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
192 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
193 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
194 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
195 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
196 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
197 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
198 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
199 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
200 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
201 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
202 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
203 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
204 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
205 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
206 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
207 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
208 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
209 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
210 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
211 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
212 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
213 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
214 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
215 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
216 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
217 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
218 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
219 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
220 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
221 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
222 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
225 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
226 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
227 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
228 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
229 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
230 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
231 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
232 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
233 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
234 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
235 	{ } /* Terminating Entry */
236 };
237 
238 MODULE_DEVICE_TABLE(usb, id_table);
239 
240 struct cp210x_serial_private {
241 #ifdef CONFIG_GPIOLIB
242 	struct gpio_chip	gc;
243 	bool			gpio_registered;
244 	u8			gpio_pushpull;
245 	u8			gpio_altfunc;
246 	u8			gpio_input;
247 #endif
248 	u8			partnum;
249 	speed_t			min_speed;
250 	speed_t			max_speed;
251 	bool			use_actual_rate;
252 };
253 
254 struct cp210x_port_private {
255 	__u8			bInterfaceNumber;
256 	bool			has_swapped_line_ctl;
257 };
258 
259 static struct usb_serial_driver cp210x_device = {
260 	.driver = {
261 		.owner =	THIS_MODULE,
262 		.name =		"cp210x",
263 	},
264 	.id_table		= id_table,
265 	.num_ports		= 1,
266 	.bulk_in_size		= 256,
267 	.bulk_out_size		= 256,
268 	.open			= cp210x_open,
269 	.close			= cp210x_close,
270 	.break_ctl		= cp210x_break_ctl,
271 	.set_termios		= cp210x_set_termios,
272 	.tx_empty		= cp210x_tx_empty,
273 	.tiocmget		= cp210x_tiocmget,
274 	.tiocmset		= cp210x_tiocmset,
275 	.attach			= cp210x_attach,
276 	.disconnect		= cp210x_disconnect,
277 	.release		= cp210x_release,
278 	.port_probe		= cp210x_port_probe,
279 	.port_remove		= cp210x_port_remove,
280 	.dtr_rts		= cp210x_dtr_rts
281 };
282 
283 static struct usb_serial_driver * const serial_drivers[] = {
284 	&cp210x_device, NULL
285 };
286 
287 /* Config request types */
288 #define REQTYPE_HOST_TO_INTERFACE	0x41
289 #define REQTYPE_INTERFACE_TO_HOST	0xc1
290 #define REQTYPE_HOST_TO_DEVICE	0x40
291 #define REQTYPE_DEVICE_TO_HOST	0xc0
292 
293 /* Config request codes */
294 #define CP210X_IFC_ENABLE	0x00
295 #define CP210X_SET_BAUDDIV	0x01
296 #define CP210X_GET_BAUDDIV	0x02
297 #define CP210X_SET_LINE_CTL	0x03
298 #define CP210X_GET_LINE_CTL	0x04
299 #define CP210X_SET_BREAK	0x05
300 #define CP210X_IMM_CHAR		0x06
301 #define CP210X_SET_MHS		0x07
302 #define CP210X_GET_MDMSTS	0x08
303 #define CP210X_SET_XON		0x09
304 #define CP210X_SET_XOFF		0x0A
305 #define CP210X_SET_EVENTMASK	0x0B
306 #define CP210X_GET_EVENTMASK	0x0C
307 #define CP210X_SET_CHAR		0x0D
308 #define CP210X_GET_CHARS	0x0E
309 #define CP210X_GET_PROPS	0x0F
310 #define CP210X_GET_COMM_STATUS	0x10
311 #define CP210X_RESET		0x11
312 #define CP210X_PURGE		0x12
313 #define CP210X_SET_FLOW		0x13
314 #define CP210X_GET_FLOW		0x14
315 #define CP210X_EMBED_EVENTS	0x15
316 #define CP210X_GET_EVENTSTATE	0x16
317 #define CP210X_SET_CHARS	0x19
318 #define CP210X_GET_BAUDRATE	0x1D
319 #define CP210X_SET_BAUDRATE	0x1E
320 #define CP210X_VENDOR_SPECIFIC	0xFF
321 
322 /* CP210X_IFC_ENABLE */
323 #define UART_ENABLE		0x0001
324 #define UART_DISABLE		0x0000
325 
326 /* CP210X_(SET|GET)_BAUDDIV */
327 #define BAUD_RATE_GEN_FREQ	0x384000
328 
329 /* CP210X_(SET|GET)_LINE_CTL */
330 #define BITS_DATA_MASK		0X0f00
331 #define BITS_DATA_5		0X0500
332 #define BITS_DATA_6		0X0600
333 #define BITS_DATA_7		0X0700
334 #define BITS_DATA_8		0X0800
335 #define BITS_DATA_9		0X0900
336 
337 #define BITS_PARITY_MASK	0x00f0
338 #define BITS_PARITY_NONE	0x0000
339 #define BITS_PARITY_ODD		0x0010
340 #define BITS_PARITY_EVEN	0x0020
341 #define BITS_PARITY_MARK	0x0030
342 #define BITS_PARITY_SPACE	0x0040
343 
344 #define BITS_STOP_MASK		0x000f
345 #define BITS_STOP_1		0x0000
346 #define BITS_STOP_1_5		0x0001
347 #define BITS_STOP_2		0x0002
348 
349 /* CP210X_SET_BREAK */
350 #define BREAK_ON		0x0001
351 #define BREAK_OFF		0x0000
352 
353 /* CP210X_(SET_MHS|GET_MDMSTS) */
354 #define CONTROL_DTR		0x0001
355 #define CONTROL_RTS		0x0002
356 #define CONTROL_CTS		0x0010
357 #define CONTROL_DSR		0x0020
358 #define CONTROL_RING		0x0040
359 #define CONTROL_DCD		0x0080
360 #define CONTROL_WRITE_DTR	0x0100
361 #define CONTROL_WRITE_RTS	0x0200
362 
363 /* CP210X_VENDOR_SPECIFIC values */
364 #define CP210X_READ_2NCONFIG	0x000E
365 #define CP210X_READ_LATCH	0x00C2
366 #define CP210X_GET_PARTNUM	0x370B
367 #define CP210X_GET_PORTCONFIG	0x370C
368 #define CP210X_GET_DEVICEMODE	0x3711
369 #define CP210X_WRITE_LATCH	0x37E1
370 
371 /* Part number definitions */
372 #define CP210X_PARTNUM_CP2101	0x01
373 #define CP210X_PARTNUM_CP2102	0x02
374 #define CP210X_PARTNUM_CP2103	0x03
375 #define CP210X_PARTNUM_CP2104	0x04
376 #define CP210X_PARTNUM_CP2105	0x05
377 #define CP210X_PARTNUM_CP2108	0x08
378 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
379 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
380 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
381 #define CP210X_PARTNUM_UNKNOWN	0xFF
382 
383 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
384 struct cp210x_comm_status {
385 	__le32   ulErrors;
386 	__le32   ulHoldReasons;
387 	__le32   ulAmountInInQueue;
388 	__le32   ulAmountInOutQueue;
389 	u8       bEofReceived;
390 	u8       bWaitForImmediate;
391 	u8       bReserved;
392 } __packed;
393 
394 /*
395  * CP210X_PURGE - 16 bits passed in wValue of USB request.
396  * SiLabs app note AN571 gives a strange description of the 4 bits:
397  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
398  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
399  */
400 #define PURGE_ALL		0x000f
401 
402 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
403 struct cp210x_flow_ctl {
404 	__le32	ulControlHandshake;
405 	__le32	ulFlowReplace;
406 	__le32	ulXonLimit;
407 	__le32	ulXoffLimit;
408 } __packed;
409 
410 /* cp210x_flow_ctl::ulControlHandshake */
411 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
412 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
413 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
414 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
415 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
416 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
417 
418 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
419 #define CP210X_SERIAL_DTR_INACTIVE	0
420 #define CP210X_SERIAL_DTR_ACTIVE	1
421 #define CP210X_SERIAL_DTR_FLOW_CTL	2
422 
423 /* cp210x_flow_ctl::ulFlowReplace */
424 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
425 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
426 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
427 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
428 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
429 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
430 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
431 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
432 
433 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
434 #define CP210X_SERIAL_RTS_INACTIVE	0
435 #define CP210X_SERIAL_RTS_ACTIVE	1
436 #define CP210X_SERIAL_RTS_FLOW_CTL	2
437 
438 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
439 struct cp210x_pin_mode {
440 	u8	eci;
441 	u8	sci;
442 } __packed;
443 
444 #define CP210X_PIN_MODE_MODEM		0
445 #define CP210X_PIN_MODE_GPIO		BIT(0)
446 
447 /*
448  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
449  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
450  */
451 struct cp210x_dual_port_config {
452 	__le16	gpio_mode;
453 	u8	__pad0[2];
454 	__le16	reset_state;
455 	u8	__pad1[4];
456 	__le16	suspend_state;
457 	u8	sci_cfg;
458 	u8	eci_cfg;
459 	u8	device_cfg;
460 } __packed;
461 
462 /*
463  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
464  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
465  */
466 struct cp210x_single_port_config {
467 	__le16	gpio_mode;
468 	u8	__pad0[2];
469 	__le16	reset_state;
470 	u8	__pad1[4];
471 	__le16	suspend_state;
472 	u8	device_cfg;
473 } __packed;
474 
475 /* GPIO modes */
476 #define CP210X_SCI_GPIO_MODE_OFFSET	9
477 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
478 
479 #define CP210X_ECI_GPIO_MODE_OFFSET	2
480 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
481 
482 #define CP210X_GPIO_MODE_OFFSET		8
483 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
484 
485 /* CP2105 port configuration values */
486 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
487 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
488 #define CP2105_GPIO1_RS485_MODE		BIT(2)
489 
490 /* CP2104 port configuration values */
491 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
492 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
493 #define CP2104_GPIO2_RS485_MODE		BIT(2)
494 
495 /* CP2102N configuration array indices */
496 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
497 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
498 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
499 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
500 
501 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
502 struct cp210x_gpio_write {
503 	u8	mask;
504 	u8	state;
505 } __packed;
506 
507 /*
508  * Helper to get interface number when we only have struct usb_serial.
509  */
510 static u8 cp210x_interface_num(struct usb_serial *serial)
511 {
512 	struct usb_host_interface *cur_altsetting;
513 
514 	cur_altsetting = serial->interface->cur_altsetting;
515 
516 	return cur_altsetting->desc.bInterfaceNumber;
517 }
518 
519 /*
520  * Reads a variable-sized block of CP210X_ registers, identified by req.
521  * Returns data into buf in native USB byte order.
522  */
523 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
524 		void *buf, int bufsize)
525 {
526 	struct usb_serial *serial = port->serial;
527 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
528 	void *dmabuf;
529 	int result;
530 
531 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
532 	if (!dmabuf) {
533 		/*
534 		 * FIXME Some callers don't bother to check for error,
535 		 * at least give them consistent junk until they are fixed
536 		 */
537 		memset(buf, 0, bufsize);
538 		return -ENOMEM;
539 	}
540 
541 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
542 			req, REQTYPE_INTERFACE_TO_HOST, 0,
543 			port_priv->bInterfaceNumber, dmabuf, bufsize,
544 			USB_CTRL_SET_TIMEOUT);
545 	if (result == bufsize) {
546 		memcpy(buf, dmabuf, bufsize);
547 		result = 0;
548 	} else {
549 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
550 				req, bufsize, result);
551 		if (result >= 0)
552 			result = -EIO;
553 
554 		/*
555 		 * FIXME Some callers don't bother to check for error,
556 		 * at least give them consistent junk until they are fixed
557 		 */
558 		memset(buf, 0, bufsize);
559 	}
560 
561 	kfree(dmabuf);
562 
563 	return result;
564 }
565 
566 /*
567  * Reads any 32-bit CP210X_ register identified by req.
568  */
569 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
570 {
571 	__le32 le32_val;
572 	int err;
573 
574 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
575 	if (err) {
576 		/*
577 		 * FIXME Some callers don't bother to check for error,
578 		 * at least give them consistent junk until they are fixed
579 		 */
580 		*val = 0;
581 		return err;
582 	}
583 
584 	*val = le32_to_cpu(le32_val);
585 
586 	return 0;
587 }
588 
589 /*
590  * Reads any 16-bit CP210X_ register identified by req.
591  */
592 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
593 {
594 	__le16 le16_val;
595 	int err;
596 
597 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
598 	if (err)
599 		return err;
600 
601 	*val = le16_to_cpu(le16_val);
602 
603 	return 0;
604 }
605 
606 /*
607  * Reads any 8-bit CP210X_ register identified by req.
608  */
609 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
610 {
611 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
612 }
613 
614 /*
615  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
616  * Returns data into buf in native USB byte order.
617  */
618 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
619 				    void *buf, int bufsize)
620 {
621 	void *dmabuf;
622 	int result;
623 
624 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
625 	if (!dmabuf)
626 		return -ENOMEM;
627 
628 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
629 				 CP210X_VENDOR_SPECIFIC, type, val,
630 				 cp210x_interface_num(serial), dmabuf, bufsize,
631 				 USB_CTRL_GET_TIMEOUT);
632 	if (result == bufsize) {
633 		memcpy(buf, dmabuf, bufsize);
634 		result = 0;
635 	} else {
636 		dev_err(&serial->interface->dev,
637 			"failed to get vendor val 0x%04x size %d: %d\n", val,
638 			bufsize, result);
639 		if (result >= 0)
640 			result = -EIO;
641 	}
642 
643 	kfree(dmabuf);
644 
645 	return result;
646 }
647 
648 /*
649  * Writes any 16-bit CP210X_ register (req) whose value is passed
650  * entirely in the wValue field of the USB request.
651  */
652 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
653 {
654 	struct usb_serial *serial = port->serial;
655 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
656 	int result;
657 
658 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
659 			req, REQTYPE_HOST_TO_INTERFACE, val,
660 			port_priv->bInterfaceNumber, NULL, 0,
661 			USB_CTRL_SET_TIMEOUT);
662 	if (result < 0) {
663 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
664 				req, result);
665 	}
666 
667 	return result;
668 }
669 
670 /*
671  * Writes a variable-sized block of CP210X_ registers, identified by req.
672  * Data in buf must be in native USB byte order.
673  */
674 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
675 		void *buf, int bufsize)
676 {
677 	struct usb_serial *serial = port->serial;
678 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
679 	void *dmabuf;
680 	int result;
681 
682 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
683 	if (!dmabuf)
684 		return -ENOMEM;
685 
686 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
687 			req, REQTYPE_HOST_TO_INTERFACE, 0,
688 			port_priv->bInterfaceNumber, dmabuf, bufsize,
689 			USB_CTRL_SET_TIMEOUT);
690 
691 	kfree(dmabuf);
692 
693 	if (result == bufsize) {
694 		result = 0;
695 	} else {
696 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
697 				req, bufsize, result);
698 		if (result >= 0)
699 			result = -EIO;
700 	}
701 
702 	return result;
703 }
704 
705 /*
706  * Writes any 32-bit CP210X_ register identified by req.
707  */
708 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
709 {
710 	__le32 le32_val;
711 
712 	le32_val = cpu_to_le32(val);
713 
714 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
715 }
716 
717 #ifdef CONFIG_GPIOLIB
718 /*
719  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
720  * Data in buf must be in native USB byte order.
721  */
722 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
723 				     u16 val, void *buf, int bufsize)
724 {
725 	void *dmabuf;
726 	int result;
727 
728 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
729 	if (!dmabuf)
730 		return -ENOMEM;
731 
732 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
733 				 CP210X_VENDOR_SPECIFIC, type, val,
734 				 cp210x_interface_num(serial), dmabuf, bufsize,
735 				 USB_CTRL_SET_TIMEOUT);
736 
737 	kfree(dmabuf);
738 
739 	if (result == bufsize) {
740 		result = 0;
741 	} else {
742 		dev_err(&serial->interface->dev,
743 			"failed to set vendor val 0x%04x size %d: %d\n", val,
744 			bufsize, result);
745 		if (result >= 0)
746 			result = -EIO;
747 	}
748 
749 	return result;
750 }
751 #endif
752 
753 /*
754  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
755  * Write a known good value 0x800, read it back.
756  * If it comes back swapped the bug is detected.
757  * Preserve the original register value.
758  */
759 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
760 {
761 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
762 	u16 line_ctl_save;
763 	u16 line_ctl_test;
764 	int err;
765 
766 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
767 	if (err)
768 		return err;
769 
770 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
771 	if (err)
772 		return err;
773 
774 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
775 	if (err)
776 		return err;
777 
778 	if (line_ctl_test == 8) {
779 		port_priv->has_swapped_line_ctl = true;
780 		line_ctl_save = swab16(line_ctl_save);
781 	}
782 
783 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
784 }
785 
786 /*
787  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
788  * to workaround cp2108 bug and get correct value.
789  */
790 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
791 {
792 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
793 	int err;
794 
795 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
796 	if (err)
797 		return err;
798 
799 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
800 	if (port_priv->has_swapped_line_ctl)
801 		*ctl = swab16(*ctl);
802 
803 	return 0;
804 }
805 
806 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
807 {
808 	int result;
809 
810 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
811 	if (result) {
812 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
813 		return result;
814 	}
815 
816 	/* Configure the termios structure */
817 	cp210x_get_termios(tty, port);
818 
819 	/* The baud rate must be initialised on cp2104 */
820 	if (tty)
821 		cp210x_change_speed(tty, port, NULL);
822 
823 	return usb_serial_generic_open(tty, port);
824 }
825 
826 static void cp210x_close(struct usb_serial_port *port)
827 {
828 	usb_serial_generic_close(port);
829 
830 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
831 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
832 
833 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
834 }
835 
836 /*
837  * Read how many bytes are waiting in the TX queue.
838  */
839 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
840 		u32 *count)
841 {
842 	struct usb_serial *serial = port->serial;
843 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
844 	struct cp210x_comm_status *sts;
845 	int result;
846 
847 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
848 	if (!sts)
849 		return -ENOMEM;
850 
851 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
852 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
853 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
854 			USB_CTRL_GET_TIMEOUT);
855 	if (result == sizeof(*sts)) {
856 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
857 		result = 0;
858 	} else {
859 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
860 		if (result >= 0)
861 			result = -EIO;
862 	}
863 
864 	kfree(sts);
865 
866 	return result;
867 }
868 
869 static bool cp210x_tx_empty(struct usb_serial_port *port)
870 {
871 	int err;
872 	u32 count;
873 
874 	err = cp210x_get_tx_queue_byte_count(port, &count);
875 	if (err)
876 		return true;
877 
878 	return !count;
879 }
880 
881 /*
882  * cp210x_get_termios
883  * Reads the baud rate, data bits, parity, stop bits and flow control mode
884  * from the device, corrects any unsupported values, and configures the
885  * termios structure to reflect the state of the device
886  */
887 static void cp210x_get_termios(struct tty_struct *tty,
888 	struct usb_serial_port *port)
889 {
890 	unsigned int baud;
891 
892 	if (tty) {
893 		cp210x_get_termios_port(tty->driver_data,
894 			&tty->termios.c_cflag, &baud);
895 		tty_encode_baud_rate(tty, baud, baud);
896 	} else {
897 		tcflag_t cflag;
898 		cflag = 0;
899 		cp210x_get_termios_port(port, &cflag, &baud);
900 	}
901 }
902 
903 /*
904  * cp210x_get_termios_port
905  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
906  */
907 static void cp210x_get_termios_port(struct usb_serial_port *port,
908 	tcflag_t *cflagp, unsigned int *baudp)
909 {
910 	struct device *dev = &port->dev;
911 	tcflag_t cflag;
912 	struct cp210x_flow_ctl flow_ctl;
913 	u32 baud;
914 	u16 bits;
915 	u32 ctl_hs;
916 
917 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
918 
919 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
920 	*baudp = baud;
921 
922 	cflag = *cflagp;
923 
924 	cp210x_get_line_ctl(port, &bits);
925 	cflag &= ~CSIZE;
926 	switch (bits & BITS_DATA_MASK) {
927 	case BITS_DATA_5:
928 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
929 		cflag |= CS5;
930 		break;
931 	case BITS_DATA_6:
932 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
933 		cflag |= CS6;
934 		break;
935 	case BITS_DATA_7:
936 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
937 		cflag |= CS7;
938 		break;
939 	case BITS_DATA_8:
940 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
941 		cflag |= CS8;
942 		break;
943 	case BITS_DATA_9:
944 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
945 		cflag |= CS8;
946 		bits &= ~BITS_DATA_MASK;
947 		bits |= BITS_DATA_8;
948 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
949 		break;
950 	default:
951 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
952 		cflag |= CS8;
953 		bits &= ~BITS_DATA_MASK;
954 		bits |= BITS_DATA_8;
955 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
956 		break;
957 	}
958 
959 	switch (bits & BITS_PARITY_MASK) {
960 	case BITS_PARITY_NONE:
961 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
962 		cflag &= ~PARENB;
963 		break;
964 	case BITS_PARITY_ODD:
965 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
966 		cflag |= (PARENB|PARODD);
967 		break;
968 	case BITS_PARITY_EVEN:
969 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
970 		cflag &= ~PARODD;
971 		cflag |= PARENB;
972 		break;
973 	case BITS_PARITY_MARK:
974 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
975 		cflag |= (PARENB|PARODD|CMSPAR);
976 		break;
977 	case BITS_PARITY_SPACE:
978 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
979 		cflag &= ~PARODD;
980 		cflag |= (PARENB|CMSPAR);
981 		break;
982 	default:
983 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
984 		cflag &= ~PARENB;
985 		bits &= ~BITS_PARITY_MASK;
986 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
987 		break;
988 	}
989 
990 	cflag &= ~CSTOPB;
991 	switch (bits & BITS_STOP_MASK) {
992 	case BITS_STOP_1:
993 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
994 		break;
995 	case BITS_STOP_1_5:
996 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
997 		bits &= ~BITS_STOP_MASK;
998 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
999 		break;
1000 	case BITS_STOP_2:
1001 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1002 		cflag |= CSTOPB;
1003 		break;
1004 	default:
1005 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
1006 		bits &= ~BITS_STOP_MASK;
1007 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1008 		break;
1009 	}
1010 
1011 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1012 			sizeof(flow_ctl));
1013 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1014 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1015 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1016 		cflag |= CRTSCTS;
1017 	} else {
1018 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1019 		cflag &= ~CRTSCTS;
1020 	}
1021 
1022 	*cflagp = cflag;
1023 }
1024 
1025 struct cp210x_rate {
1026 	speed_t rate;
1027 	speed_t high;
1028 };
1029 
1030 static const struct cp210x_rate cp210x_an205_table1[] = {
1031 	{ 300, 300 },
1032 	{ 600, 600 },
1033 	{ 1200, 1200 },
1034 	{ 1800, 1800 },
1035 	{ 2400, 2400 },
1036 	{ 4000, 4000 },
1037 	{ 4800, 4803 },
1038 	{ 7200, 7207 },
1039 	{ 9600, 9612 },
1040 	{ 14400, 14428 },
1041 	{ 16000, 16062 },
1042 	{ 19200, 19250 },
1043 	{ 28800, 28912 },
1044 	{ 38400, 38601 },
1045 	{ 51200, 51558 },
1046 	{ 56000, 56280 },
1047 	{ 57600, 58053 },
1048 	{ 64000, 64111 },
1049 	{ 76800, 77608 },
1050 	{ 115200, 117028 },
1051 	{ 128000, 129347 },
1052 	{ 153600, 156868 },
1053 	{ 230400, 237832 },
1054 	{ 250000, 254234 },
1055 	{ 256000, 273066 },
1056 	{ 460800, 491520 },
1057 	{ 500000, 567138 },
1058 	{ 576000, 670254 },
1059 	{ 921600, UINT_MAX }
1060 };
1061 
1062 /*
1063  * Quantises the baud rate as per AN205 Table 1
1064  */
1065 static speed_t cp210x_get_an205_rate(speed_t baud)
1066 {
1067 	int i;
1068 
1069 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1070 		if (baud <= cp210x_an205_table1[i].high)
1071 			break;
1072 	}
1073 
1074 	return cp210x_an205_table1[i].rate;
1075 }
1076 
1077 static speed_t cp210x_get_actual_rate(speed_t baud)
1078 {
1079 	unsigned int prescale = 1;
1080 	unsigned int div;
1081 
1082 	if (baud <= 365)
1083 		prescale = 4;
1084 
1085 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1086 	baud = 48000000 / (2 * prescale * div);
1087 
1088 	return baud;
1089 }
1090 
1091 /*
1092  * CP2101 supports the following baud rates:
1093  *
1094  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1095  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1096  *
1097  * CP2102 and CP2103 support the following additional rates:
1098  *
1099  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1100  *	576000
1101  *
1102  * The device will map a requested rate to a supported one, but the result
1103  * of requests for rates greater than 1053257 is undefined (see AN205).
1104  *
1105  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1106  * respectively, with an error less than 1%. The actual rates are determined
1107  * by
1108  *
1109  *	div = round(freq / (2 x prescale x request))
1110  *	actual = freq / (2 x prescale x div)
1111  *
1112  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1113  * or 1 otherwise.
1114  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1115  * otherwise.
1116  */
1117 static void cp210x_change_speed(struct tty_struct *tty,
1118 		struct usb_serial_port *port, struct ktermios *old_termios)
1119 {
1120 	struct usb_serial *serial = port->serial;
1121 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1122 	u32 baud;
1123 
1124 	/*
1125 	 * This maps the requested rate to the actual rate, a valid rate on
1126 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1127 	 *
1128 	 * NOTE: B0 is not implemented.
1129 	 */
1130 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1131 
1132 	if (priv->use_actual_rate)
1133 		baud = cp210x_get_actual_rate(baud);
1134 	else if (baud < 1000000)
1135 		baud = cp210x_get_an205_rate(baud);
1136 
1137 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1138 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1139 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1140 		if (old_termios)
1141 			baud = old_termios->c_ospeed;
1142 		else
1143 			baud = 9600;
1144 	}
1145 
1146 	tty_encode_baud_rate(tty, baud, baud);
1147 }
1148 
1149 static void cp210x_set_termios(struct tty_struct *tty,
1150 		struct usb_serial_port *port, struct ktermios *old_termios)
1151 {
1152 	struct device *dev = &port->dev;
1153 	unsigned int cflag, old_cflag;
1154 	u16 bits;
1155 
1156 	cflag = tty->termios.c_cflag;
1157 	old_cflag = old_termios->c_cflag;
1158 
1159 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1160 		cp210x_change_speed(tty, port, old_termios);
1161 
1162 	/* If the number of data bits is to be updated */
1163 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1164 		cp210x_get_line_ctl(port, &bits);
1165 		bits &= ~BITS_DATA_MASK;
1166 		switch (cflag & CSIZE) {
1167 		case CS5:
1168 			bits |= BITS_DATA_5;
1169 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1170 			break;
1171 		case CS6:
1172 			bits |= BITS_DATA_6;
1173 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1174 			break;
1175 		case CS7:
1176 			bits |= BITS_DATA_7;
1177 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1178 			break;
1179 		case CS8:
1180 		default:
1181 			bits |= BITS_DATA_8;
1182 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1183 			break;
1184 		}
1185 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1186 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1187 	}
1188 
1189 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1190 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1191 		cp210x_get_line_ctl(port, &bits);
1192 		bits &= ~BITS_PARITY_MASK;
1193 		if (cflag & PARENB) {
1194 			if (cflag & CMSPAR) {
1195 				if (cflag & PARODD) {
1196 					bits |= BITS_PARITY_MARK;
1197 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1198 				} else {
1199 					bits |= BITS_PARITY_SPACE;
1200 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1201 				}
1202 			} else {
1203 				if (cflag & PARODD) {
1204 					bits |= BITS_PARITY_ODD;
1205 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1206 				} else {
1207 					bits |= BITS_PARITY_EVEN;
1208 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1209 				}
1210 			}
1211 		}
1212 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1213 			dev_dbg(dev, "Parity mode not supported by device\n");
1214 	}
1215 
1216 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1217 		cp210x_get_line_ctl(port, &bits);
1218 		bits &= ~BITS_STOP_MASK;
1219 		if (cflag & CSTOPB) {
1220 			bits |= BITS_STOP_2;
1221 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1222 		} else {
1223 			bits |= BITS_STOP_1;
1224 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1225 		}
1226 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1227 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1228 	}
1229 
1230 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1231 		struct cp210x_flow_ctl flow_ctl;
1232 		u32 ctl_hs;
1233 		u32 flow_repl;
1234 
1235 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1236 				sizeof(flow_ctl));
1237 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1238 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1239 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1240 				__func__, ctl_hs, flow_repl);
1241 
1242 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1243 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1244 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1245 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1246 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1247 		if (cflag & CRTSCTS) {
1248 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1249 
1250 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1251 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1252 					CP210X_SERIAL_RTS_FLOW_CTL);
1253 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1254 		} else {
1255 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1256 
1257 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1258 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1259 					CP210X_SERIAL_RTS_ACTIVE);
1260 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1261 		}
1262 
1263 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1264 				__func__, ctl_hs, flow_repl);
1265 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1266 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1267 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1268 				sizeof(flow_ctl));
1269 	}
1270 
1271 }
1272 
1273 static int cp210x_tiocmset(struct tty_struct *tty,
1274 		unsigned int set, unsigned int clear)
1275 {
1276 	struct usb_serial_port *port = tty->driver_data;
1277 	return cp210x_tiocmset_port(port, set, clear);
1278 }
1279 
1280 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1281 		unsigned int set, unsigned int clear)
1282 {
1283 	u16 control = 0;
1284 
1285 	if (set & TIOCM_RTS) {
1286 		control |= CONTROL_RTS;
1287 		control |= CONTROL_WRITE_RTS;
1288 	}
1289 	if (set & TIOCM_DTR) {
1290 		control |= CONTROL_DTR;
1291 		control |= CONTROL_WRITE_DTR;
1292 	}
1293 	if (clear & TIOCM_RTS) {
1294 		control &= ~CONTROL_RTS;
1295 		control |= CONTROL_WRITE_RTS;
1296 	}
1297 	if (clear & TIOCM_DTR) {
1298 		control &= ~CONTROL_DTR;
1299 		control |= CONTROL_WRITE_DTR;
1300 	}
1301 
1302 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1303 
1304 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1305 }
1306 
1307 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1308 {
1309 	if (on)
1310 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1311 	else
1312 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1313 }
1314 
1315 static int cp210x_tiocmget(struct tty_struct *tty)
1316 {
1317 	struct usb_serial_port *port = tty->driver_data;
1318 	u8 control;
1319 	int result;
1320 
1321 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1322 	if (result)
1323 		return result;
1324 
1325 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1326 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1327 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1328 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1329 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1330 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1331 
1332 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1333 
1334 	return result;
1335 }
1336 
1337 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1338 {
1339 	struct usb_serial_port *port = tty->driver_data;
1340 	u16 state;
1341 
1342 	if (break_state == 0)
1343 		state = BREAK_OFF;
1344 	else
1345 		state = BREAK_ON;
1346 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1347 		state == BREAK_OFF ? "off" : "on");
1348 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1349 }
1350 
1351 #ifdef CONFIG_GPIOLIB
1352 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1353 {
1354 	struct usb_serial *serial = gpiochip_get_data(gc);
1355 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1356 
1357 	if (priv->gpio_altfunc & BIT(offset))
1358 		return -ENODEV;
1359 
1360 	return 0;
1361 }
1362 
1363 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1364 {
1365 	struct usb_serial *serial = gpiochip_get_data(gc);
1366 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1367 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1368 	int result;
1369 	u8 buf;
1370 
1371 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1372 		req_type = REQTYPE_INTERFACE_TO_HOST;
1373 
1374 	result = usb_autopm_get_interface(serial->interface);
1375 	if (result)
1376 		return result;
1377 
1378 	result = cp210x_read_vendor_block(serial, req_type,
1379 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1380 	usb_autopm_put_interface(serial->interface);
1381 	if (result < 0)
1382 		return result;
1383 
1384 	return !!(buf & BIT(gpio));
1385 }
1386 
1387 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1388 {
1389 	struct usb_serial *serial = gpiochip_get_data(gc);
1390 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1391 	struct cp210x_gpio_write buf;
1392 	int result;
1393 
1394 	if (value == 1)
1395 		buf.state = BIT(gpio);
1396 	else
1397 		buf.state = 0;
1398 
1399 	buf.mask = BIT(gpio);
1400 
1401 	result = usb_autopm_get_interface(serial->interface);
1402 	if (result)
1403 		goto out;
1404 
1405 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1406 		result = cp210x_write_vendor_block(serial,
1407 						   REQTYPE_HOST_TO_INTERFACE,
1408 						   CP210X_WRITE_LATCH, &buf,
1409 						   sizeof(buf));
1410 	} else {
1411 		u16 wIndex = buf.state << 8 | buf.mask;
1412 
1413 		result = usb_control_msg(serial->dev,
1414 					 usb_sndctrlpipe(serial->dev, 0),
1415 					 CP210X_VENDOR_SPECIFIC,
1416 					 REQTYPE_HOST_TO_DEVICE,
1417 					 CP210X_WRITE_LATCH,
1418 					 wIndex,
1419 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1420 	}
1421 
1422 	usb_autopm_put_interface(serial->interface);
1423 out:
1424 	if (result < 0) {
1425 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1426 				result);
1427 	}
1428 }
1429 
1430 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1431 {
1432 	struct usb_serial *serial = gpiochip_get_data(gc);
1433 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1434 
1435 	return priv->gpio_input & BIT(gpio);
1436 }
1437 
1438 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1439 {
1440 	struct usb_serial *serial = gpiochip_get_data(gc);
1441 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1442 
1443 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1444 		/* hardware does not support an input mode */
1445 		return -ENOTSUPP;
1446 	}
1447 
1448 	/* push-pull pins cannot be changed to be inputs */
1449 	if (priv->gpio_pushpull & BIT(gpio))
1450 		return -EINVAL;
1451 
1452 	/* make sure to release pin if it is being driven low */
1453 	cp210x_gpio_set(gc, gpio, 1);
1454 
1455 	priv->gpio_input |= BIT(gpio);
1456 
1457 	return 0;
1458 }
1459 
1460 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1461 					int value)
1462 {
1463 	struct usb_serial *serial = gpiochip_get_data(gc);
1464 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1465 
1466 	priv->gpio_input &= ~BIT(gpio);
1467 	cp210x_gpio_set(gc, gpio, value);
1468 
1469 	return 0;
1470 }
1471 
1472 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1473 				  unsigned long config)
1474 {
1475 	struct usb_serial *serial = gpiochip_get_data(gc);
1476 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1477 	enum pin_config_param param = pinconf_to_config_param(config);
1478 
1479 	/* Succeed only if in correct mode (this can't be set at runtime) */
1480 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1481 	    (priv->gpio_pushpull & BIT(gpio)))
1482 		return 0;
1483 
1484 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1485 	    !(priv->gpio_pushpull & BIT(gpio)))
1486 		return 0;
1487 
1488 	return -ENOTSUPP;
1489 }
1490 
1491 /*
1492  * This function is for configuring GPIO using shared pins, where other signals
1493  * are made unavailable by configuring the use of GPIO. This is believed to be
1494  * only applicable to the cp2105 at this point, the other devices supported by
1495  * this driver that provide GPIO do so in a way that does not impact other
1496  * signals and are thus expected to have very different initialisation.
1497  */
1498 static int cp2105_gpioconf_init(struct usb_serial *serial)
1499 {
1500 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1501 	struct cp210x_pin_mode mode;
1502 	struct cp210x_dual_port_config config;
1503 	u8 intf_num = cp210x_interface_num(serial);
1504 	u8 iface_config;
1505 	int result;
1506 
1507 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1508 					  CP210X_GET_DEVICEMODE, &mode,
1509 					  sizeof(mode));
1510 	if (result < 0)
1511 		return result;
1512 
1513 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1514 					  CP210X_GET_PORTCONFIG, &config,
1515 					  sizeof(config));
1516 	if (result < 0)
1517 		return result;
1518 
1519 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1520 	if (intf_num == 0) {
1521 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1522 			/* mark all GPIOs of this interface as reserved */
1523 			priv->gpio_altfunc = 0xff;
1524 			return 0;
1525 		}
1526 
1527 		iface_config = config.eci_cfg;
1528 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1529 						CP210X_ECI_GPIO_MODE_MASK) >>
1530 						CP210X_ECI_GPIO_MODE_OFFSET);
1531 		priv->gc.ngpio = 2;
1532 	} else if (intf_num == 1) {
1533 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1534 			/* mark all GPIOs of this interface as reserved */
1535 			priv->gpio_altfunc = 0xff;
1536 			return 0;
1537 		}
1538 
1539 		iface_config = config.sci_cfg;
1540 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1541 						CP210X_SCI_GPIO_MODE_MASK) >>
1542 						CP210X_SCI_GPIO_MODE_OFFSET);
1543 		priv->gc.ngpio = 3;
1544 	} else {
1545 		return -ENODEV;
1546 	}
1547 
1548 	/* mark all pins which are not in GPIO mode */
1549 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1550 		priv->gpio_altfunc |= BIT(0);
1551 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1552 			CP2105_GPIO1_RS485_MODE))
1553 		priv->gpio_altfunc |= BIT(1);
1554 
1555 	/* driver implementation for CP2105 only supports outputs */
1556 	priv->gpio_input = 0;
1557 
1558 	return 0;
1559 }
1560 
1561 static int cp2104_gpioconf_init(struct usb_serial *serial)
1562 {
1563 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1564 	struct cp210x_single_port_config config;
1565 	u8 iface_config;
1566 	u8 gpio_latch;
1567 	int result;
1568 	u8 i;
1569 
1570 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1571 					  CP210X_GET_PORTCONFIG, &config,
1572 					  sizeof(config));
1573 	if (result < 0)
1574 		return result;
1575 
1576 	priv->gc.ngpio = 4;
1577 
1578 	iface_config = config.device_cfg;
1579 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1580 					CP210X_GPIO_MODE_MASK) >>
1581 					CP210X_GPIO_MODE_OFFSET);
1582 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1583 					CP210X_GPIO_MODE_MASK) >>
1584 					CP210X_GPIO_MODE_OFFSET);
1585 
1586 	/* mark all pins which are not in GPIO mode */
1587 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1588 		priv->gpio_altfunc |= BIT(0);
1589 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1590 		priv->gpio_altfunc |= BIT(1);
1591 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1592 		priv->gpio_altfunc |= BIT(2);
1593 
1594 	/*
1595 	 * Like CP2102N, CP2104 has also no strict input and output pin
1596 	 * modes.
1597 	 * Do the same input mode emulation as CP2102N.
1598 	 */
1599 	for (i = 0; i < priv->gc.ngpio; ++i) {
1600 		/*
1601 		 * Set direction to "input" iff pin is open-drain and reset
1602 		 * value is 1.
1603 		 */
1604 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1605 			priv->gpio_input |= BIT(i);
1606 	}
1607 
1608 	return 0;
1609 }
1610 
1611 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1612 {
1613 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1614 	const u16 config_size = 0x02a6;
1615 	u8 gpio_rst_latch;
1616 	u8 config_version;
1617 	u8 gpio_pushpull;
1618 	u8 *config_buf;
1619 	u8 gpio_latch;
1620 	u8 gpio_ctrl;
1621 	int result;
1622 	u8 i;
1623 
1624 	/*
1625 	 * Retrieve device configuration from the device.
1626 	 * The array received contains all customization settings done at the
1627 	 * factory/manufacturer. Format of the array is documented at the
1628 	 * time of writing at:
1629 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1630 	 */
1631 	config_buf = kmalloc(config_size, GFP_KERNEL);
1632 	if (!config_buf)
1633 		return -ENOMEM;
1634 
1635 	result = cp210x_read_vendor_block(serial,
1636 					  REQTYPE_DEVICE_TO_HOST,
1637 					  CP210X_READ_2NCONFIG,
1638 					  config_buf,
1639 					  config_size);
1640 	if (result < 0) {
1641 		kfree(config_buf);
1642 		return result;
1643 	}
1644 
1645 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1646 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1647 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1648 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1649 
1650 	kfree(config_buf);
1651 
1652 	/* Make sure this is a config format we understand. */
1653 	if (config_version != 0x01)
1654 		return -ENOTSUPP;
1655 
1656 	priv->gc.ngpio = 4;
1657 
1658 	/*
1659 	 * Get default pin states after reset. Needed so we can determine
1660 	 * the direction of an open-drain pin.
1661 	 */
1662 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1663 
1664 	/* 0 indicates open-drain mode, 1 is push-pull */
1665 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1666 
1667 	/* 0 indicates GPIO mode, 1 is alternate function */
1668 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1669 
1670 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1671 		/*
1672 		 * For the QFN28 package, GPIO4-6 are controlled by
1673 		 * the low three bits of the mode/latch fields.
1674 		 * Contrary to the document linked above, the bits for
1675 		 * the SUSPEND pins are elsewhere.  No alternate
1676 		 * function is available for these pins.
1677 		 */
1678 		priv->gc.ngpio = 7;
1679 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1680 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1681 	}
1682 
1683 	/*
1684 	 * The CP2102N does not strictly has input and output pin modes,
1685 	 * it only knows open-drain and push-pull modes which is set at
1686 	 * factory. An open-drain pin can function both as an
1687 	 * input or an output. We emulate input mode for open-drain pins
1688 	 * by making sure they are not driven low, and we do not allow
1689 	 * push-pull pins to be set as an input.
1690 	 */
1691 	for (i = 0; i < priv->gc.ngpio; ++i) {
1692 		/*
1693 		 * Set direction to "input" iff pin is open-drain and reset
1694 		 * value is 1.
1695 		 */
1696 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1697 			priv->gpio_input |= BIT(i);
1698 	}
1699 
1700 	return 0;
1701 }
1702 
1703 static int cp210x_gpio_init(struct usb_serial *serial)
1704 {
1705 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1706 	int result;
1707 
1708 	switch (priv->partnum) {
1709 	case CP210X_PARTNUM_CP2104:
1710 		result = cp2104_gpioconf_init(serial);
1711 		break;
1712 	case CP210X_PARTNUM_CP2105:
1713 		result = cp2105_gpioconf_init(serial);
1714 		break;
1715 	case CP210X_PARTNUM_CP2102N_QFN28:
1716 	case CP210X_PARTNUM_CP2102N_QFN24:
1717 	case CP210X_PARTNUM_CP2102N_QFN20:
1718 		result = cp2102n_gpioconf_init(serial);
1719 		break;
1720 	default:
1721 		return 0;
1722 	}
1723 
1724 	if (result < 0)
1725 		return result;
1726 
1727 	priv->gc.label = "cp210x";
1728 	priv->gc.request = cp210x_gpio_request;
1729 	priv->gc.get_direction = cp210x_gpio_direction_get;
1730 	priv->gc.direction_input = cp210x_gpio_direction_input;
1731 	priv->gc.direction_output = cp210x_gpio_direction_output;
1732 	priv->gc.get = cp210x_gpio_get;
1733 	priv->gc.set = cp210x_gpio_set;
1734 	priv->gc.set_config = cp210x_gpio_set_config;
1735 	priv->gc.owner = THIS_MODULE;
1736 	priv->gc.parent = &serial->interface->dev;
1737 	priv->gc.base = -1;
1738 	priv->gc.can_sleep = true;
1739 
1740 	result = gpiochip_add_data(&priv->gc, serial);
1741 	if (!result)
1742 		priv->gpio_registered = true;
1743 
1744 	return result;
1745 }
1746 
1747 static void cp210x_gpio_remove(struct usb_serial *serial)
1748 {
1749 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1750 
1751 	if (priv->gpio_registered) {
1752 		gpiochip_remove(&priv->gc);
1753 		priv->gpio_registered = false;
1754 	}
1755 }
1756 
1757 #else
1758 
1759 static int cp210x_gpio_init(struct usb_serial *serial)
1760 {
1761 	return 0;
1762 }
1763 
1764 static void cp210x_gpio_remove(struct usb_serial *serial)
1765 {
1766 	/* Nothing to do */
1767 }
1768 
1769 #endif
1770 
1771 static int cp210x_port_probe(struct usb_serial_port *port)
1772 {
1773 	struct usb_serial *serial = port->serial;
1774 	struct cp210x_port_private *port_priv;
1775 	int ret;
1776 
1777 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1778 	if (!port_priv)
1779 		return -ENOMEM;
1780 
1781 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1782 
1783 	usb_set_serial_port_data(port, port_priv);
1784 
1785 	ret = cp210x_detect_swapped_line_ctl(port);
1786 	if (ret) {
1787 		kfree(port_priv);
1788 		return ret;
1789 	}
1790 
1791 	return 0;
1792 }
1793 
1794 static int cp210x_port_remove(struct usb_serial_port *port)
1795 {
1796 	struct cp210x_port_private *port_priv;
1797 
1798 	port_priv = usb_get_serial_port_data(port);
1799 	kfree(port_priv);
1800 
1801 	return 0;
1802 }
1803 
1804 static void cp210x_init_max_speed(struct usb_serial *serial)
1805 {
1806 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1807 	bool use_actual_rate = false;
1808 	speed_t min = 300;
1809 	speed_t max;
1810 
1811 	switch (priv->partnum) {
1812 	case CP210X_PARTNUM_CP2101:
1813 		max = 921600;
1814 		break;
1815 	case CP210X_PARTNUM_CP2102:
1816 	case CP210X_PARTNUM_CP2103:
1817 		max = 1000000;
1818 		break;
1819 	case CP210X_PARTNUM_CP2104:
1820 		use_actual_rate = true;
1821 		max = 2000000;
1822 		break;
1823 	case CP210X_PARTNUM_CP2108:
1824 		max = 2000000;
1825 		break;
1826 	case CP210X_PARTNUM_CP2105:
1827 		if (cp210x_interface_num(serial) == 0) {
1828 			use_actual_rate = true;
1829 			max = 2000000;	/* ECI */
1830 		} else {
1831 			min = 2400;
1832 			max = 921600;	/* SCI */
1833 		}
1834 		break;
1835 	case CP210X_PARTNUM_CP2102N_QFN28:
1836 	case CP210X_PARTNUM_CP2102N_QFN24:
1837 	case CP210X_PARTNUM_CP2102N_QFN20:
1838 		use_actual_rate = true;
1839 		max = 3000000;
1840 		break;
1841 	default:
1842 		max = 2000000;
1843 		break;
1844 	}
1845 
1846 	priv->min_speed = min;
1847 	priv->max_speed = max;
1848 	priv->use_actual_rate = use_actual_rate;
1849 }
1850 
1851 static int cp210x_attach(struct usb_serial *serial)
1852 {
1853 	int result;
1854 	struct cp210x_serial_private *priv;
1855 
1856 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1857 	if (!priv)
1858 		return -ENOMEM;
1859 
1860 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1861 					  CP210X_GET_PARTNUM, &priv->partnum,
1862 					  sizeof(priv->partnum));
1863 	if (result < 0) {
1864 		dev_warn(&serial->interface->dev,
1865 			 "querying part number failed\n");
1866 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1867 	}
1868 
1869 	usb_set_serial_data(serial, priv);
1870 
1871 	cp210x_init_max_speed(serial);
1872 
1873 	result = cp210x_gpio_init(serial);
1874 	if (result < 0) {
1875 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1876 				result);
1877 	}
1878 
1879 	return 0;
1880 }
1881 
1882 static void cp210x_disconnect(struct usb_serial *serial)
1883 {
1884 	cp210x_gpio_remove(serial);
1885 }
1886 
1887 static void cp210x_release(struct usb_serial *serial)
1888 {
1889 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1890 
1891 	cp210x_gpio_remove(serial);
1892 
1893 	kfree(priv);
1894 }
1895 
1896 module_usb_serial_driver(serial_drivers, id_table);
1897 
1898 MODULE_DESCRIPTION(DRIVER_DESC);
1899 MODULE_LICENSE("GPL v2");
1900