xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision fb8d6c8d)
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, 0x8056) }, /* Lorenz Messtechnik devices */
84 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
85 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
86 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
87 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
88 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
89 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
90 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
91 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
92 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
93 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
94 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
95 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
96 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
97 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
98 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
99 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
100 	{ USB_DEVICE(0x10C4, 0x817C) }, /* CESINEL MEDCAL N Power Quality Monitor */
101 	{ USB_DEVICE(0x10C4, 0x817D) }, /* CESINEL MEDCAL NT Power Quality Monitor */
102 	{ USB_DEVICE(0x10C4, 0x817E) }, /* CESINEL MEDCAL S Power Quality Monitor */
103 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
104 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
105 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
106 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
107 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
108 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
109 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
110 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
111 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
112 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
113 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
114 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
115 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
116 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
117 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
118 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
119 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
120 	{ USB_DEVICE(0x10C4, 0x82EF) }, /* CESINEL FALCO 6105 AC Power Supply */
121 	{ USB_DEVICE(0x10C4, 0x82F1) }, /* CESINEL MEDCAL EFD Earth Fault Detector */
122 	{ USB_DEVICE(0x10C4, 0x82F2) }, /* CESINEL MEDCAL ST Network Analyzer */
123 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
124 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
125 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
126 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
127 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
128 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
129 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
130 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
131 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
132 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
133 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
134 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
135 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
136 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
137 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
138 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
139 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
140 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
141 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
142 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
143 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
144 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
145 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
146 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
147 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
148 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
149 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
150 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
151 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
152 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
153 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
154 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
155 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
156 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
157 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
158 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
159 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
160 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
161 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
162 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
163 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
164 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
165 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
166 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
167 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
168 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
169 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
170 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
171 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
172 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
173 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
174 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
175 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
176 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
177 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
178 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
179 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
180 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
181 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
182 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
183 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
184 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
185 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
186 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
187 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
188 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
189 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
190 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
191 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
192 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
193 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
194 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
195 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
196 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
197 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
198 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
199 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
200 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
201 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
202 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
203 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
204 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
205 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
206 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
207 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
208 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
209 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
210 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
211 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
212 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
213 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
214 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
215 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
216 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
217 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
218 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
219 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
220 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
221 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
222 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
226 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
227 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
228 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
229 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
230 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
231 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
232 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
233 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
234 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
235 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
236 	{ } /* Terminating Entry */
237 };
238 
239 MODULE_DEVICE_TABLE(usb, id_table);
240 
241 struct cp210x_serial_private {
242 #ifdef CONFIG_GPIOLIB
243 	struct gpio_chip	gc;
244 	bool			gpio_registered;
245 	u8			gpio_pushpull;
246 	u8			gpio_altfunc;
247 	u8			gpio_input;
248 #endif
249 	u8			partnum;
250 	speed_t			min_speed;
251 	speed_t			max_speed;
252 	bool			use_actual_rate;
253 };
254 
255 struct cp210x_port_private {
256 	__u8			bInterfaceNumber;
257 	bool			has_swapped_line_ctl;
258 };
259 
260 static struct usb_serial_driver cp210x_device = {
261 	.driver = {
262 		.owner =	THIS_MODULE,
263 		.name =		"cp210x",
264 	},
265 	.id_table		= id_table,
266 	.num_ports		= 1,
267 	.bulk_in_size		= 256,
268 	.bulk_out_size		= 256,
269 	.open			= cp210x_open,
270 	.close			= cp210x_close,
271 	.break_ctl		= cp210x_break_ctl,
272 	.set_termios		= cp210x_set_termios,
273 	.tx_empty		= cp210x_tx_empty,
274 	.tiocmget		= cp210x_tiocmget,
275 	.tiocmset		= cp210x_tiocmset,
276 	.attach			= cp210x_attach,
277 	.disconnect		= cp210x_disconnect,
278 	.release		= cp210x_release,
279 	.port_probe		= cp210x_port_probe,
280 	.port_remove		= cp210x_port_remove,
281 	.dtr_rts		= cp210x_dtr_rts
282 };
283 
284 static struct usb_serial_driver * const serial_drivers[] = {
285 	&cp210x_device, NULL
286 };
287 
288 /* Config request types */
289 #define REQTYPE_HOST_TO_INTERFACE	0x41
290 #define REQTYPE_INTERFACE_TO_HOST	0xc1
291 #define REQTYPE_HOST_TO_DEVICE	0x40
292 #define REQTYPE_DEVICE_TO_HOST	0xc0
293 
294 /* Config request codes */
295 #define CP210X_IFC_ENABLE	0x00
296 #define CP210X_SET_BAUDDIV	0x01
297 #define CP210X_GET_BAUDDIV	0x02
298 #define CP210X_SET_LINE_CTL	0x03
299 #define CP210X_GET_LINE_CTL	0x04
300 #define CP210X_SET_BREAK	0x05
301 #define CP210X_IMM_CHAR		0x06
302 #define CP210X_SET_MHS		0x07
303 #define CP210X_GET_MDMSTS	0x08
304 #define CP210X_SET_XON		0x09
305 #define CP210X_SET_XOFF		0x0A
306 #define CP210X_SET_EVENTMASK	0x0B
307 #define CP210X_GET_EVENTMASK	0x0C
308 #define CP210X_SET_CHAR		0x0D
309 #define CP210X_GET_CHARS	0x0E
310 #define CP210X_GET_PROPS	0x0F
311 #define CP210X_GET_COMM_STATUS	0x10
312 #define CP210X_RESET		0x11
313 #define CP210X_PURGE		0x12
314 #define CP210X_SET_FLOW		0x13
315 #define CP210X_GET_FLOW		0x14
316 #define CP210X_EMBED_EVENTS	0x15
317 #define CP210X_GET_EVENTSTATE	0x16
318 #define CP210X_SET_CHARS	0x19
319 #define CP210X_GET_BAUDRATE	0x1D
320 #define CP210X_SET_BAUDRATE	0x1E
321 #define CP210X_VENDOR_SPECIFIC	0xFF
322 
323 /* CP210X_IFC_ENABLE */
324 #define UART_ENABLE		0x0001
325 #define UART_DISABLE		0x0000
326 
327 /* CP210X_(SET|GET)_BAUDDIV */
328 #define BAUD_RATE_GEN_FREQ	0x384000
329 
330 /* CP210X_(SET|GET)_LINE_CTL */
331 #define BITS_DATA_MASK		0X0f00
332 #define BITS_DATA_5		0X0500
333 #define BITS_DATA_6		0X0600
334 #define BITS_DATA_7		0X0700
335 #define BITS_DATA_8		0X0800
336 #define BITS_DATA_9		0X0900
337 
338 #define BITS_PARITY_MASK	0x00f0
339 #define BITS_PARITY_NONE	0x0000
340 #define BITS_PARITY_ODD		0x0010
341 #define BITS_PARITY_EVEN	0x0020
342 #define BITS_PARITY_MARK	0x0030
343 #define BITS_PARITY_SPACE	0x0040
344 
345 #define BITS_STOP_MASK		0x000f
346 #define BITS_STOP_1		0x0000
347 #define BITS_STOP_1_5		0x0001
348 #define BITS_STOP_2		0x0002
349 
350 /* CP210X_SET_BREAK */
351 #define BREAK_ON		0x0001
352 #define BREAK_OFF		0x0000
353 
354 /* CP210X_(SET_MHS|GET_MDMSTS) */
355 #define CONTROL_DTR		0x0001
356 #define CONTROL_RTS		0x0002
357 #define CONTROL_CTS		0x0010
358 #define CONTROL_DSR		0x0020
359 #define CONTROL_RING		0x0040
360 #define CONTROL_DCD		0x0080
361 #define CONTROL_WRITE_DTR	0x0100
362 #define CONTROL_WRITE_RTS	0x0200
363 
364 /* CP210X_VENDOR_SPECIFIC values */
365 #define CP210X_READ_2NCONFIG	0x000E
366 #define CP210X_READ_LATCH	0x00C2
367 #define CP210X_GET_PARTNUM	0x370B
368 #define CP210X_GET_PORTCONFIG	0x370C
369 #define CP210X_GET_DEVICEMODE	0x3711
370 #define CP210X_WRITE_LATCH	0x37E1
371 
372 /* Part number definitions */
373 #define CP210X_PARTNUM_CP2101	0x01
374 #define CP210X_PARTNUM_CP2102	0x02
375 #define CP210X_PARTNUM_CP2103	0x03
376 #define CP210X_PARTNUM_CP2104	0x04
377 #define CP210X_PARTNUM_CP2105	0x05
378 #define CP210X_PARTNUM_CP2108	0x08
379 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
380 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
381 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
382 #define CP210X_PARTNUM_UNKNOWN	0xFF
383 
384 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
385 struct cp210x_comm_status {
386 	__le32   ulErrors;
387 	__le32   ulHoldReasons;
388 	__le32   ulAmountInInQueue;
389 	__le32   ulAmountInOutQueue;
390 	u8       bEofReceived;
391 	u8       bWaitForImmediate;
392 	u8       bReserved;
393 } __packed;
394 
395 /*
396  * CP210X_PURGE - 16 bits passed in wValue of USB request.
397  * SiLabs app note AN571 gives a strange description of the 4 bits:
398  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
399  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
400  */
401 #define PURGE_ALL		0x000f
402 
403 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
404 struct cp210x_flow_ctl {
405 	__le32	ulControlHandshake;
406 	__le32	ulFlowReplace;
407 	__le32	ulXonLimit;
408 	__le32	ulXoffLimit;
409 } __packed;
410 
411 /* cp210x_flow_ctl::ulControlHandshake */
412 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
413 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
414 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
415 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
416 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
417 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
418 
419 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
420 #define CP210X_SERIAL_DTR_INACTIVE	0
421 #define CP210X_SERIAL_DTR_ACTIVE	1
422 #define CP210X_SERIAL_DTR_FLOW_CTL	2
423 
424 /* cp210x_flow_ctl::ulFlowReplace */
425 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
426 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
427 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
428 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
429 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
430 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
431 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
432 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
433 
434 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
435 #define CP210X_SERIAL_RTS_INACTIVE	0
436 #define CP210X_SERIAL_RTS_ACTIVE	1
437 #define CP210X_SERIAL_RTS_FLOW_CTL	2
438 
439 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
440 struct cp210x_pin_mode {
441 	u8	eci;
442 	u8	sci;
443 } __packed;
444 
445 #define CP210X_PIN_MODE_MODEM		0
446 #define CP210X_PIN_MODE_GPIO		BIT(0)
447 
448 /*
449  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
450  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
451  */
452 struct cp210x_dual_port_config {
453 	__le16	gpio_mode;
454 	u8	__pad0[2];
455 	__le16	reset_state;
456 	u8	__pad1[4];
457 	__le16	suspend_state;
458 	u8	sci_cfg;
459 	u8	eci_cfg;
460 	u8	device_cfg;
461 } __packed;
462 
463 /*
464  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
465  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
466  */
467 struct cp210x_single_port_config {
468 	__le16	gpio_mode;
469 	u8	__pad0[2];
470 	__le16	reset_state;
471 	u8	__pad1[4];
472 	__le16	suspend_state;
473 	u8	device_cfg;
474 } __packed;
475 
476 /* GPIO modes */
477 #define CP210X_SCI_GPIO_MODE_OFFSET	9
478 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
479 
480 #define CP210X_ECI_GPIO_MODE_OFFSET	2
481 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
482 
483 #define CP210X_GPIO_MODE_OFFSET		8
484 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
485 
486 /* CP2105 port configuration values */
487 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
488 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
489 #define CP2105_GPIO1_RS485_MODE		BIT(2)
490 
491 /* CP2104 port configuration values */
492 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
493 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
494 #define CP2104_GPIO2_RS485_MODE		BIT(2)
495 
496 /* CP2102N configuration array indices */
497 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
498 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
499 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
500 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
501 
502 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
503 struct cp210x_gpio_write {
504 	u8	mask;
505 	u8	state;
506 } __packed;
507 
508 /*
509  * Helper to get interface number when we only have struct usb_serial.
510  */
511 static u8 cp210x_interface_num(struct usb_serial *serial)
512 {
513 	struct usb_host_interface *cur_altsetting;
514 
515 	cur_altsetting = serial->interface->cur_altsetting;
516 
517 	return cur_altsetting->desc.bInterfaceNumber;
518 }
519 
520 /*
521  * Reads a variable-sized block of CP210X_ registers, identified by req.
522  * Returns data into buf in native USB byte order.
523  */
524 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
525 		void *buf, int bufsize)
526 {
527 	struct usb_serial *serial = port->serial;
528 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
529 	void *dmabuf;
530 	int result;
531 
532 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
533 	if (!dmabuf) {
534 		/*
535 		 * FIXME Some callers don't bother to check for error,
536 		 * at least give them consistent junk until they are fixed
537 		 */
538 		memset(buf, 0, bufsize);
539 		return -ENOMEM;
540 	}
541 
542 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
543 			req, REQTYPE_INTERFACE_TO_HOST, 0,
544 			port_priv->bInterfaceNumber, dmabuf, bufsize,
545 			USB_CTRL_SET_TIMEOUT);
546 	if (result == bufsize) {
547 		memcpy(buf, dmabuf, bufsize);
548 		result = 0;
549 	} else {
550 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
551 				req, bufsize, result);
552 		if (result >= 0)
553 			result = -EIO;
554 
555 		/*
556 		 * FIXME Some callers don't bother to check for error,
557 		 * at least give them consistent junk until they are fixed
558 		 */
559 		memset(buf, 0, bufsize);
560 	}
561 
562 	kfree(dmabuf);
563 
564 	return result;
565 }
566 
567 /*
568  * Reads any 32-bit CP210X_ register identified by req.
569  */
570 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
571 {
572 	__le32 le32_val;
573 	int err;
574 
575 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
576 	if (err) {
577 		/*
578 		 * FIXME Some callers don't bother to check for error,
579 		 * at least give them consistent junk until they are fixed
580 		 */
581 		*val = 0;
582 		return err;
583 	}
584 
585 	*val = le32_to_cpu(le32_val);
586 
587 	return 0;
588 }
589 
590 /*
591  * Reads any 16-bit CP210X_ register identified by req.
592  */
593 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
594 {
595 	__le16 le16_val;
596 	int err;
597 
598 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
599 	if (err)
600 		return err;
601 
602 	*val = le16_to_cpu(le16_val);
603 
604 	return 0;
605 }
606 
607 /*
608  * Reads any 8-bit CP210X_ register identified by req.
609  */
610 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
611 {
612 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
613 }
614 
615 /*
616  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
617  * Returns data into buf in native USB byte order.
618  */
619 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
620 				    void *buf, int bufsize)
621 {
622 	void *dmabuf;
623 	int result;
624 
625 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
626 	if (!dmabuf)
627 		return -ENOMEM;
628 
629 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
630 				 CP210X_VENDOR_SPECIFIC, type, val,
631 				 cp210x_interface_num(serial), dmabuf, bufsize,
632 				 USB_CTRL_GET_TIMEOUT);
633 	if (result == bufsize) {
634 		memcpy(buf, dmabuf, bufsize);
635 		result = 0;
636 	} else {
637 		dev_err(&serial->interface->dev,
638 			"failed to get vendor val 0x%04x size %d: %d\n", val,
639 			bufsize, result);
640 		if (result >= 0)
641 			result = -EIO;
642 	}
643 
644 	kfree(dmabuf);
645 
646 	return result;
647 }
648 
649 /*
650  * Writes any 16-bit CP210X_ register (req) whose value is passed
651  * entirely in the wValue field of the USB request.
652  */
653 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
654 {
655 	struct usb_serial *serial = port->serial;
656 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
657 	int result;
658 
659 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
660 			req, REQTYPE_HOST_TO_INTERFACE, val,
661 			port_priv->bInterfaceNumber, NULL, 0,
662 			USB_CTRL_SET_TIMEOUT);
663 	if (result < 0) {
664 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
665 				req, result);
666 	}
667 
668 	return result;
669 }
670 
671 /*
672  * Writes a variable-sized block of CP210X_ registers, identified by req.
673  * Data in buf must be in native USB byte order.
674  */
675 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
676 		void *buf, int bufsize)
677 {
678 	struct usb_serial *serial = port->serial;
679 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
680 	void *dmabuf;
681 	int result;
682 
683 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
684 	if (!dmabuf)
685 		return -ENOMEM;
686 
687 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
688 			req, REQTYPE_HOST_TO_INTERFACE, 0,
689 			port_priv->bInterfaceNumber, dmabuf, bufsize,
690 			USB_CTRL_SET_TIMEOUT);
691 
692 	kfree(dmabuf);
693 
694 	if (result == bufsize) {
695 		result = 0;
696 	} else {
697 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
698 				req, bufsize, result);
699 		if (result >= 0)
700 			result = -EIO;
701 	}
702 
703 	return result;
704 }
705 
706 /*
707  * Writes any 32-bit CP210X_ register identified by req.
708  */
709 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
710 {
711 	__le32 le32_val;
712 
713 	le32_val = cpu_to_le32(val);
714 
715 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
716 }
717 
718 #ifdef CONFIG_GPIOLIB
719 /*
720  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
721  * Data in buf must be in native USB byte order.
722  */
723 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
724 				     u16 val, void *buf, int bufsize)
725 {
726 	void *dmabuf;
727 	int result;
728 
729 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
730 	if (!dmabuf)
731 		return -ENOMEM;
732 
733 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
734 				 CP210X_VENDOR_SPECIFIC, type, val,
735 				 cp210x_interface_num(serial), dmabuf, bufsize,
736 				 USB_CTRL_SET_TIMEOUT);
737 
738 	kfree(dmabuf);
739 
740 	if (result == bufsize) {
741 		result = 0;
742 	} else {
743 		dev_err(&serial->interface->dev,
744 			"failed to set vendor val 0x%04x size %d: %d\n", val,
745 			bufsize, result);
746 		if (result >= 0)
747 			result = -EIO;
748 	}
749 
750 	return result;
751 }
752 #endif
753 
754 /*
755  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
756  * Write a known good value 0x800, read it back.
757  * If it comes back swapped the bug is detected.
758  * Preserve the original register value.
759  */
760 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
761 {
762 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
763 	u16 line_ctl_save;
764 	u16 line_ctl_test;
765 	int err;
766 
767 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
768 	if (err)
769 		return err;
770 
771 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
772 	if (err)
773 		return err;
774 
775 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
776 	if (err)
777 		return err;
778 
779 	if (line_ctl_test == 8) {
780 		port_priv->has_swapped_line_ctl = true;
781 		line_ctl_save = swab16(line_ctl_save);
782 	}
783 
784 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
785 }
786 
787 /*
788  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
789  * to workaround cp2108 bug and get correct value.
790  */
791 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
792 {
793 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
794 	int err;
795 
796 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
797 	if (err)
798 		return err;
799 
800 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
801 	if (port_priv->has_swapped_line_ctl)
802 		*ctl = swab16(*ctl);
803 
804 	return 0;
805 }
806 
807 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
808 {
809 	int result;
810 
811 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
812 	if (result) {
813 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
814 		return result;
815 	}
816 
817 	/* Configure the termios structure */
818 	cp210x_get_termios(tty, port);
819 
820 	/* The baud rate must be initialised on cp2104 */
821 	if (tty)
822 		cp210x_change_speed(tty, port, NULL);
823 
824 	return usb_serial_generic_open(tty, port);
825 }
826 
827 static void cp210x_close(struct usb_serial_port *port)
828 {
829 	usb_serial_generic_close(port);
830 
831 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
832 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
833 
834 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
835 }
836 
837 /*
838  * Read how many bytes are waiting in the TX queue.
839  */
840 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
841 		u32 *count)
842 {
843 	struct usb_serial *serial = port->serial;
844 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
845 	struct cp210x_comm_status *sts;
846 	int result;
847 
848 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
849 	if (!sts)
850 		return -ENOMEM;
851 
852 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
853 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
854 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
855 			USB_CTRL_GET_TIMEOUT);
856 	if (result == sizeof(*sts)) {
857 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
858 		result = 0;
859 	} else {
860 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
861 		if (result >= 0)
862 			result = -EIO;
863 	}
864 
865 	kfree(sts);
866 
867 	return result;
868 }
869 
870 static bool cp210x_tx_empty(struct usb_serial_port *port)
871 {
872 	int err;
873 	u32 count;
874 
875 	err = cp210x_get_tx_queue_byte_count(port, &count);
876 	if (err)
877 		return true;
878 
879 	return !count;
880 }
881 
882 /*
883  * cp210x_get_termios
884  * Reads the baud rate, data bits, parity, stop bits and flow control mode
885  * from the device, corrects any unsupported values, and configures the
886  * termios structure to reflect the state of the device
887  */
888 static void cp210x_get_termios(struct tty_struct *tty,
889 	struct usb_serial_port *port)
890 {
891 	unsigned int baud;
892 
893 	if (tty) {
894 		cp210x_get_termios_port(tty->driver_data,
895 			&tty->termios.c_cflag, &baud);
896 		tty_encode_baud_rate(tty, baud, baud);
897 	} else {
898 		tcflag_t cflag;
899 		cflag = 0;
900 		cp210x_get_termios_port(port, &cflag, &baud);
901 	}
902 }
903 
904 /*
905  * cp210x_get_termios_port
906  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
907  */
908 static void cp210x_get_termios_port(struct usb_serial_port *port,
909 	tcflag_t *cflagp, unsigned int *baudp)
910 {
911 	struct device *dev = &port->dev;
912 	tcflag_t cflag;
913 	struct cp210x_flow_ctl flow_ctl;
914 	u32 baud;
915 	u16 bits;
916 	u32 ctl_hs;
917 
918 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
919 
920 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
921 	*baudp = baud;
922 
923 	cflag = *cflagp;
924 
925 	cp210x_get_line_ctl(port, &bits);
926 	cflag &= ~CSIZE;
927 	switch (bits & BITS_DATA_MASK) {
928 	case BITS_DATA_5:
929 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
930 		cflag |= CS5;
931 		break;
932 	case BITS_DATA_6:
933 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
934 		cflag |= CS6;
935 		break;
936 	case BITS_DATA_7:
937 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
938 		cflag |= CS7;
939 		break;
940 	case BITS_DATA_8:
941 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
942 		cflag |= CS8;
943 		break;
944 	case BITS_DATA_9:
945 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
946 		cflag |= CS8;
947 		bits &= ~BITS_DATA_MASK;
948 		bits |= BITS_DATA_8;
949 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
950 		break;
951 	default:
952 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
953 		cflag |= CS8;
954 		bits &= ~BITS_DATA_MASK;
955 		bits |= BITS_DATA_8;
956 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
957 		break;
958 	}
959 
960 	switch (bits & BITS_PARITY_MASK) {
961 	case BITS_PARITY_NONE:
962 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
963 		cflag &= ~PARENB;
964 		break;
965 	case BITS_PARITY_ODD:
966 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
967 		cflag |= (PARENB|PARODD);
968 		break;
969 	case BITS_PARITY_EVEN:
970 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
971 		cflag &= ~PARODD;
972 		cflag |= PARENB;
973 		break;
974 	case BITS_PARITY_MARK:
975 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
976 		cflag |= (PARENB|PARODD|CMSPAR);
977 		break;
978 	case BITS_PARITY_SPACE:
979 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
980 		cflag &= ~PARODD;
981 		cflag |= (PARENB|CMSPAR);
982 		break;
983 	default:
984 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
985 		cflag &= ~PARENB;
986 		bits &= ~BITS_PARITY_MASK;
987 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
988 		break;
989 	}
990 
991 	cflag &= ~CSTOPB;
992 	switch (bits & BITS_STOP_MASK) {
993 	case BITS_STOP_1:
994 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
995 		break;
996 	case BITS_STOP_1_5:
997 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
998 		bits &= ~BITS_STOP_MASK;
999 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1000 		break;
1001 	case BITS_STOP_2:
1002 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1003 		cflag |= CSTOPB;
1004 		break;
1005 	default:
1006 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
1007 		bits &= ~BITS_STOP_MASK;
1008 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1009 		break;
1010 	}
1011 
1012 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1013 			sizeof(flow_ctl));
1014 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1015 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1016 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1017 		cflag |= CRTSCTS;
1018 	} else {
1019 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1020 		cflag &= ~CRTSCTS;
1021 	}
1022 
1023 	*cflagp = cflag;
1024 }
1025 
1026 struct cp210x_rate {
1027 	speed_t rate;
1028 	speed_t high;
1029 };
1030 
1031 static const struct cp210x_rate cp210x_an205_table1[] = {
1032 	{ 300, 300 },
1033 	{ 600, 600 },
1034 	{ 1200, 1200 },
1035 	{ 1800, 1800 },
1036 	{ 2400, 2400 },
1037 	{ 4000, 4000 },
1038 	{ 4800, 4803 },
1039 	{ 7200, 7207 },
1040 	{ 9600, 9612 },
1041 	{ 14400, 14428 },
1042 	{ 16000, 16062 },
1043 	{ 19200, 19250 },
1044 	{ 28800, 28912 },
1045 	{ 38400, 38601 },
1046 	{ 51200, 51558 },
1047 	{ 56000, 56280 },
1048 	{ 57600, 58053 },
1049 	{ 64000, 64111 },
1050 	{ 76800, 77608 },
1051 	{ 115200, 117028 },
1052 	{ 128000, 129347 },
1053 	{ 153600, 156868 },
1054 	{ 230400, 237832 },
1055 	{ 250000, 254234 },
1056 	{ 256000, 273066 },
1057 	{ 460800, 491520 },
1058 	{ 500000, 567138 },
1059 	{ 576000, 670254 },
1060 	{ 921600, UINT_MAX }
1061 };
1062 
1063 /*
1064  * Quantises the baud rate as per AN205 Table 1
1065  */
1066 static speed_t cp210x_get_an205_rate(speed_t baud)
1067 {
1068 	int i;
1069 
1070 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1071 		if (baud <= cp210x_an205_table1[i].high)
1072 			break;
1073 	}
1074 
1075 	return cp210x_an205_table1[i].rate;
1076 }
1077 
1078 static speed_t cp210x_get_actual_rate(speed_t baud)
1079 {
1080 	unsigned int prescale = 1;
1081 	unsigned int div;
1082 
1083 	if (baud <= 365)
1084 		prescale = 4;
1085 
1086 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1087 	baud = 48000000 / (2 * prescale * div);
1088 
1089 	return baud;
1090 }
1091 
1092 /*
1093  * CP2101 supports the following baud rates:
1094  *
1095  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1096  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1097  *
1098  * CP2102 and CP2103 support the following additional rates:
1099  *
1100  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1101  *	576000
1102  *
1103  * The device will map a requested rate to a supported one, but the result
1104  * of requests for rates greater than 1053257 is undefined (see AN205).
1105  *
1106  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1107  * respectively, with an error less than 1%. The actual rates are determined
1108  * by
1109  *
1110  *	div = round(freq / (2 x prescale x request))
1111  *	actual = freq / (2 x prescale x div)
1112  *
1113  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1114  * or 1 otherwise.
1115  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1116  * otherwise.
1117  */
1118 static void cp210x_change_speed(struct tty_struct *tty,
1119 		struct usb_serial_port *port, struct ktermios *old_termios)
1120 {
1121 	struct usb_serial *serial = port->serial;
1122 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1123 	u32 baud;
1124 
1125 	/*
1126 	 * This maps the requested rate to the actual rate, a valid rate on
1127 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1128 	 *
1129 	 * NOTE: B0 is not implemented.
1130 	 */
1131 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1132 
1133 	if (priv->use_actual_rate)
1134 		baud = cp210x_get_actual_rate(baud);
1135 	else if (baud < 1000000)
1136 		baud = cp210x_get_an205_rate(baud);
1137 
1138 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1139 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1140 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1141 		if (old_termios)
1142 			baud = old_termios->c_ospeed;
1143 		else
1144 			baud = 9600;
1145 	}
1146 
1147 	tty_encode_baud_rate(tty, baud, baud);
1148 }
1149 
1150 static void cp210x_set_termios(struct tty_struct *tty,
1151 		struct usb_serial_port *port, struct ktermios *old_termios)
1152 {
1153 	struct device *dev = &port->dev;
1154 	unsigned int cflag, old_cflag;
1155 	u16 bits;
1156 
1157 	cflag = tty->termios.c_cflag;
1158 	old_cflag = old_termios->c_cflag;
1159 
1160 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1161 		cp210x_change_speed(tty, port, old_termios);
1162 
1163 	/* If the number of data bits is to be updated */
1164 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1165 		cp210x_get_line_ctl(port, &bits);
1166 		bits &= ~BITS_DATA_MASK;
1167 		switch (cflag & CSIZE) {
1168 		case CS5:
1169 			bits |= BITS_DATA_5;
1170 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1171 			break;
1172 		case CS6:
1173 			bits |= BITS_DATA_6;
1174 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1175 			break;
1176 		case CS7:
1177 			bits |= BITS_DATA_7;
1178 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1179 			break;
1180 		case CS8:
1181 		default:
1182 			bits |= BITS_DATA_8;
1183 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1184 			break;
1185 		}
1186 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1187 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1188 	}
1189 
1190 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1191 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1192 		cp210x_get_line_ctl(port, &bits);
1193 		bits &= ~BITS_PARITY_MASK;
1194 		if (cflag & PARENB) {
1195 			if (cflag & CMSPAR) {
1196 				if (cflag & PARODD) {
1197 					bits |= BITS_PARITY_MARK;
1198 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1199 				} else {
1200 					bits |= BITS_PARITY_SPACE;
1201 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1202 				}
1203 			} else {
1204 				if (cflag & PARODD) {
1205 					bits |= BITS_PARITY_ODD;
1206 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1207 				} else {
1208 					bits |= BITS_PARITY_EVEN;
1209 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1210 				}
1211 			}
1212 		}
1213 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1214 			dev_dbg(dev, "Parity mode not supported by device\n");
1215 	}
1216 
1217 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1218 		cp210x_get_line_ctl(port, &bits);
1219 		bits &= ~BITS_STOP_MASK;
1220 		if (cflag & CSTOPB) {
1221 			bits |= BITS_STOP_2;
1222 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1223 		} else {
1224 			bits |= BITS_STOP_1;
1225 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1226 		}
1227 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1228 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1229 	}
1230 
1231 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1232 		struct cp210x_flow_ctl flow_ctl;
1233 		u32 ctl_hs;
1234 		u32 flow_repl;
1235 
1236 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1237 				sizeof(flow_ctl));
1238 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1239 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1240 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1241 				__func__, ctl_hs, flow_repl);
1242 
1243 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1244 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1245 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1246 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1247 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1248 		if (cflag & CRTSCTS) {
1249 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1250 
1251 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1252 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1253 					CP210X_SERIAL_RTS_FLOW_CTL);
1254 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1255 		} else {
1256 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1257 
1258 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1259 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1260 					CP210X_SERIAL_RTS_ACTIVE);
1261 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1262 		}
1263 
1264 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1265 				__func__, ctl_hs, flow_repl);
1266 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1267 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1268 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1269 				sizeof(flow_ctl));
1270 	}
1271 
1272 }
1273 
1274 static int cp210x_tiocmset(struct tty_struct *tty,
1275 		unsigned int set, unsigned int clear)
1276 {
1277 	struct usb_serial_port *port = tty->driver_data;
1278 	return cp210x_tiocmset_port(port, set, clear);
1279 }
1280 
1281 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1282 		unsigned int set, unsigned int clear)
1283 {
1284 	u16 control = 0;
1285 
1286 	if (set & TIOCM_RTS) {
1287 		control |= CONTROL_RTS;
1288 		control |= CONTROL_WRITE_RTS;
1289 	}
1290 	if (set & TIOCM_DTR) {
1291 		control |= CONTROL_DTR;
1292 		control |= CONTROL_WRITE_DTR;
1293 	}
1294 	if (clear & TIOCM_RTS) {
1295 		control &= ~CONTROL_RTS;
1296 		control |= CONTROL_WRITE_RTS;
1297 	}
1298 	if (clear & TIOCM_DTR) {
1299 		control &= ~CONTROL_DTR;
1300 		control |= CONTROL_WRITE_DTR;
1301 	}
1302 
1303 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1304 
1305 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1306 }
1307 
1308 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1309 {
1310 	if (on)
1311 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1312 	else
1313 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1314 }
1315 
1316 static int cp210x_tiocmget(struct tty_struct *tty)
1317 {
1318 	struct usb_serial_port *port = tty->driver_data;
1319 	u8 control;
1320 	int result;
1321 
1322 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1323 	if (result)
1324 		return result;
1325 
1326 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1327 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1328 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1329 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1330 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1331 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1332 
1333 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1334 
1335 	return result;
1336 }
1337 
1338 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1339 {
1340 	struct usb_serial_port *port = tty->driver_data;
1341 	u16 state;
1342 
1343 	if (break_state == 0)
1344 		state = BREAK_OFF;
1345 	else
1346 		state = BREAK_ON;
1347 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1348 		state == BREAK_OFF ? "off" : "on");
1349 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1350 }
1351 
1352 #ifdef CONFIG_GPIOLIB
1353 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1354 {
1355 	struct usb_serial *serial = gpiochip_get_data(gc);
1356 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1357 
1358 	if (priv->gpio_altfunc & BIT(offset))
1359 		return -ENODEV;
1360 
1361 	return 0;
1362 }
1363 
1364 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1365 {
1366 	struct usb_serial *serial = gpiochip_get_data(gc);
1367 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1368 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1369 	int result;
1370 	u8 buf;
1371 
1372 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1373 		req_type = REQTYPE_INTERFACE_TO_HOST;
1374 
1375 	result = usb_autopm_get_interface(serial->interface);
1376 	if (result)
1377 		return result;
1378 
1379 	result = cp210x_read_vendor_block(serial, req_type,
1380 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1381 	usb_autopm_put_interface(serial->interface);
1382 	if (result < 0)
1383 		return result;
1384 
1385 	return !!(buf & BIT(gpio));
1386 }
1387 
1388 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1389 {
1390 	struct usb_serial *serial = gpiochip_get_data(gc);
1391 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1392 	struct cp210x_gpio_write buf;
1393 	int result;
1394 
1395 	if (value == 1)
1396 		buf.state = BIT(gpio);
1397 	else
1398 		buf.state = 0;
1399 
1400 	buf.mask = BIT(gpio);
1401 
1402 	result = usb_autopm_get_interface(serial->interface);
1403 	if (result)
1404 		goto out;
1405 
1406 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1407 		result = cp210x_write_vendor_block(serial,
1408 						   REQTYPE_HOST_TO_INTERFACE,
1409 						   CP210X_WRITE_LATCH, &buf,
1410 						   sizeof(buf));
1411 	} else {
1412 		u16 wIndex = buf.state << 8 | buf.mask;
1413 
1414 		result = usb_control_msg(serial->dev,
1415 					 usb_sndctrlpipe(serial->dev, 0),
1416 					 CP210X_VENDOR_SPECIFIC,
1417 					 REQTYPE_HOST_TO_DEVICE,
1418 					 CP210X_WRITE_LATCH,
1419 					 wIndex,
1420 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1421 	}
1422 
1423 	usb_autopm_put_interface(serial->interface);
1424 out:
1425 	if (result < 0) {
1426 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1427 				result);
1428 	}
1429 }
1430 
1431 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1432 {
1433 	struct usb_serial *serial = gpiochip_get_data(gc);
1434 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1435 
1436 	return priv->gpio_input & BIT(gpio);
1437 }
1438 
1439 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1440 {
1441 	struct usb_serial *serial = gpiochip_get_data(gc);
1442 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1443 
1444 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1445 		/* hardware does not support an input mode */
1446 		return -ENOTSUPP;
1447 	}
1448 
1449 	/* push-pull pins cannot be changed to be inputs */
1450 	if (priv->gpio_pushpull & BIT(gpio))
1451 		return -EINVAL;
1452 
1453 	/* make sure to release pin if it is being driven low */
1454 	cp210x_gpio_set(gc, gpio, 1);
1455 
1456 	priv->gpio_input |= BIT(gpio);
1457 
1458 	return 0;
1459 }
1460 
1461 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1462 					int value)
1463 {
1464 	struct usb_serial *serial = gpiochip_get_data(gc);
1465 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1466 
1467 	priv->gpio_input &= ~BIT(gpio);
1468 	cp210x_gpio_set(gc, gpio, value);
1469 
1470 	return 0;
1471 }
1472 
1473 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1474 				  unsigned long config)
1475 {
1476 	struct usb_serial *serial = gpiochip_get_data(gc);
1477 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1478 	enum pin_config_param param = pinconf_to_config_param(config);
1479 
1480 	/* Succeed only if in correct mode (this can't be set at runtime) */
1481 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1482 	    (priv->gpio_pushpull & BIT(gpio)))
1483 		return 0;
1484 
1485 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1486 	    !(priv->gpio_pushpull & BIT(gpio)))
1487 		return 0;
1488 
1489 	return -ENOTSUPP;
1490 }
1491 
1492 /*
1493  * This function is for configuring GPIO using shared pins, where other signals
1494  * are made unavailable by configuring the use of GPIO. This is believed to be
1495  * only applicable to the cp2105 at this point, the other devices supported by
1496  * this driver that provide GPIO do so in a way that does not impact other
1497  * signals and are thus expected to have very different initialisation.
1498  */
1499 static int cp2105_gpioconf_init(struct usb_serial *serial)
1500 {
1501 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1502 	struct cp210x_pin_mode mode;
1503 	struct cp210x_dual_port_config config;
1504 	u8 intf_num = cp210x_interface_num(serial);
1505 	u8 iface_config;
1506 	int result;
1507 
1508 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1509 					  CP210X_GET_DEVICEMODE, &mode,
1510 					  sizeof(mode));
1511 	if (result < 0)
1512 		return result;
1513 
1514 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1515 					  CP210X_GET_PORTCONFIG, &config,
1516 					  sizeof(config));
1517 	if (result < 0)
1518 		return result;
1519 
1520 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1521 	if (intf_num == 0) {
1522 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1523 			/* mark all GPIOs of this interface as reserved */
1524 			priv->gpio_altfunc = 0xff;
1525 			return 0;
1526 		}
1527 
1528 		iface_config = config.eci_cfg;
1529 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1530 						CP210X_ECI_GPIO_MODE_MASK) >>
1531 						CP210X_ECI_GPIO_MODE_OFFSET);
1532 		priv->gc.ngpio = 2;
1533 	} else if (intf_num == 1) {
1534 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1535 			/* mark all GPIOs of this interface as reserved */
1536 			priv->gpio_altfunc = 0xff;
1537 			return 0;
1538 		}
1539 
1540 		iface_config = config.sci_cfg;
1541 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1542 						CP210X_SCI_GPIO_MODE_MASK) >>
1543 						CP210X_SCI_GPIO_MODE_OFFSET);
1544 		priv->gc.ngpio = 3;
1545 	} else {
1546 		return -ENODEV;
1547 	}
1548 
1549 	/* mark all pins which are not in GPIO mode */
1550 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1551 		priv->gpio_altfunc |= BIT(0);
1552 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1553 			CP2105_GPIO1_RS485_MODE))
1554 		priv->gpio_altfunc |= BIT(1);
1555 
1556 	/* driver implementation for CP2105 only supports outputs */
1557 	priv->gpio_input = 0;
1558 
1559 	return 0;
1560 }
1561 
1562 static int cp2104_gpioconf_init(struct usb_serial *serial)
1563 {
1564 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1565 	struct cp210x_single_port_config config;
1566 	u8 iface_config;
1567 	u8 gpio_latch;
1568 	int result;
1569 	u8 i;
1570 
1571 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1572 					  CP210X_GET_PORTCONFIG, &config,
1573 					  sizeof(config));
1574 	if (result < 0)
1575 		return result;
1576 
1577 	priv->gc.ngpio = 4;
1578 
1579 	iface_config = config.device_cfg;
1580 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1581 					CP210X_GPIO_MODE_MASK) >>
1582 					CP210X_GPIO_MODE_OFFSET);
1583 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1584 					CP210X_GPIO_MODE_MASK) >>
1585 					CP210X_GPIO_MODE_OFFSET);
1586 
1587 	/* mark all pins which are not in GPIO mode */
1588 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1589 		priv->gpio_altfunc |= BIT(0);
1590 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1591 		priv->gpio_altfunc |= BIT(1);
1592 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1593 		priv->gpio_altfunc |= BIT(2);
1594 
1595 	/*
1596 	 * Like CP2102N, CP2104 has also no strict input and output pin
1597 	 * modes.
1598 	 * Do the same input mode emulation as CP2102N.
1599 	 */
1600 	for (i = 0; i < priv->gc.ngpio; ++i) {
1601 		/*
1602 		 * Set direction to "input" iff pin is open-drain and reset
1603 		 * value is 1.
1604 		 */
1605 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1606 			priv->gpio_input |= BIT(i);
1607 	}
1608 
1609 	return 0;
1610 }
1611 
1612 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1613 {
1614 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1615 	const u16 config_size = 0x02a6;
1616 	u8 gpio_rst_latch;
1617 	u8 config_version;
1618 	u8 gpio_pushpull;
1619 	u8 *config_buf;
1620 	u8 gpio_latch;
1621 	u8 gpio_ctrl;
1622 	int result;
1623 	u8 i;
1624 
1625 	/*
1626 	 * Retrieve device configuration from the device.
1627 	 * The array received contains all customization settings done at the
1628 	 * factory/manufacturer. Format of the array is documented at the
1629 	 * time of writing at:
1630 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1631 	 */
1632 	config_buf = kmalloc(config_size, GFP_KERNEL);
1633 	if (!config_buf)
1634 		return -ENOMEM;
1635 
1636 	result = cp210x_read_vendor_block(serial,
1637 					  REQTYPE_DEVICE_TO_HOST,
1638 					  CP210X_READ_2NCONFIG,
1639 					  config_buf,
1640 					  config_size);
1641 	if (result < 0) {
1642 		kfree(config_buf);
1643 		return result;
1644 	}
1645 
1646 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1647 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1648 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1649 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1650 
1651 	kfree(config_buf);
1652 
1653 	/* Make sure this is a config format we understand. */
1654 	if (config_version != 0x01)
1655 		return -ENOTSUPP;
1656 
1657 	priv->gc.ngpio = 4;
1658 
1659 	/*
1660 	 * Get default pin states after reset. Needed so we can determine
1661 	 * the direction of an open-drain pin.
1662 	 */
1663 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1664 
1665 	/* 0 indicates open-drain mode, 1 is push-pull */
1666 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1667 
1668 	/* 0 indicates GPIO mode, 1 is alternate function */
1669 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1670 
1671 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1672 		/*
1673 		 * For the QFN28 package, GPIO4-6 are controlled by
1674 		 * the low three bits of the mode/latch fields.
1675 		 * Contrary to the document linked above, the bits for
1676 		 * the SUSPEND pins are elsewhere.  No alternate
1677 		 * function is available for these pins.
1678 		 */
1679 		priv->gc.ngpio = 7;
1680 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1681 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1682 	}
1683 
1684 	/*
1685 	 * The CP2102N does not strictly has input and output pin modes,
1686 	 * it only knows open-drain and push-pull modes which is set at
1687 	 * factory. An open-drain pin can function both as an
1688 	 * input or an output. We emulate input mode for open-drain pins
1689 	 * by making sure they are not driven low, and we do not allow
1690 	 * push-pull pins to be set as an input.
1691 	 */
1692 	for (i = 0; i < priv->gc.ngpio; ++i) {
1693 		/*
1694 		 * Set direction to "input" iff pin is open-drain and reset
1695 		 * value is 1.
1696 		 */
1697 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1698 			priv->gpio_input |= BIT(i);
1699 	}
1700 
1701 	return 0;
1702 }
1703 
1704 static int cp210x_gpio_init(struct usb_serial *serial)
1705 {
1706 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1707 	int result;
1708 
1709 	switch (priv->partnum) {
1710 	case CP210X_PARTNUM_CP2104:
1711 		result = cp2104_gpioconf_init(serial);
1712 		break;
1713 	case CP210X_PARTNUM_CP2105:
1714 		result = cp2105_gpioconf_init(serial);
1715 		break;
1716 	case CP210X_PARTNUM_CP2102N_QFN28:
1717 	case CP210X_PARTNUM_CP2102N_QFN24:
1718 	case CP210X_PARTNUM_CP2102N_QFN20:
1719 		result = cp2102n_gpioconf_init(serial);
1720 		break;
1721 	default:
1722 		return 0;
1723 	}
1724 
1725 	if (result < 0)
1726 		return result;
1727 
1728 	priv->gc.label = "cp210x";
1729 	priv->gc.request = cp210x_gpio_request;
1730 	priv->gc.get_direction = cp210x_gpio_direction_get;
1731 	priv->gc.direction_input = cp210x_gpio_direction_input;
1732 	priv->gc.direction_output = cp210x_gpio_direction_output;
1733 	priv->gc.get = cp210x_gpio_get;
1734 	priv->gc.set = cp210x_gpio_set;
1735 	priv->gc.set_config = cp210x_gpio_set_config;
1736 	priv->gc.owner = THIS_MODULE;
1737 	priv->gc.parent = &serial->interface->dev;
1738 	priv->gc.base = -1;
1739 	priv->gc.can_sleep = true;
1740 
1741 	result = gpiochip_add_data(&priv->gc, serial);
1742 	if (!result)
1743 		priv->gpio_registered = true;
1744 
1745 	return result;
1746 }
1747 
1748 static void cp210x_gpio_remove(struct usb_serial *serial)
1749 {
1750 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1751 
1752 	if (priv->gpio_registered) {
1753 		gpiochip_remove(&priv->gc);
1754 		priv->gpio_registered = false;
1755 	}
1756 }
1757 
1758 #else
1759 
1760 static int cp210x_gpio_init(struct usb_serial *serial)
1761 {
1762 	return 0;
1763 }
1764 
1765 static void cp210x_gpio_remove(struct usb_serial *serial)
1766 {
1767 	/* Nothing to do */
1768 }
1769 
1770 #endif
1771 
1772 static int cp210x_port_probe(struct usb_serial_port *port)
1773 {
1774 	struct usb_serial *serial = port->serial;
1775 	struct cp210x_port_private *port_priv;
1776 	int ret;
1777 
1778 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1779 	if (!port_priv)
1780 		return -ENOMEM;
1781 
1782 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1783 
1784 	usb_set_serial_port_data(port, port_priv);
1785 
1786 	ret = cp210x_detect_swapped_line_ctl(port);
1787 	if (ret) {
1788 		kfree(port_priv);
1789 		return ret;
1790 	}
1791 
1792 	return 0;
1793 }
1794 
1795 static int cp210x_port_remove(struct usb_serial_port *port)
1796 {
1797 	struct cp210x_port_private *port_priv;
1798 
1799 	port_priv = usb_get_serial_port_data(port);
1800 	kfree(port_priv);
1801 
1802 	return 0;
1803 }
1804 
1805 static void cp210x_init_max_speed(struct usb_serial *serial)
1806 {
1807 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1808 	bool use_actual_rate = false;
1809 	speed_t min = 300;
1810 	speed_t max;
1811 
1812 	switch (priv->partnum) {
1813 	case CP210X_PARTNUM_CP2101:
1814 		max = 921600;
1815 		break;
1816 	case CP210X_PARTNUM_CP2102:
1817 	case CP210X_PARTNUM_CP2103:
1818 		max = 1000000;
1819 		break;
1820 	case CP210X_PARTNUM_CP2104:
1821 		use_actual_rate = true;
1822 		max = 2000000;
1823 		break;
1824 	case CP210X_PARTNUM_CP2108:
1825 		max = 2000000;
1826 		break;
1827 	case CP210X_PARTNUM_CP2105:
1828 		if (cp210x_interface_num(serial) == 0) {
1829 			use_actual_rate = true;
1830 			max = 2000000;	/* ECI */
1831 		} else {
1832 			min = 2400;
1833 			max = 921600;	/* SCI */
1834 		}
1835 		break;
1836 	case CP210X_PARTNUM_CP2102N_QFN28:
1837 	case CP210X_PARTNUM_CP2102N_QFN24:
1838 	case CP210X_PARTNUM_CP2102N_QFN20:
1839 		use_actual_rate = true;
1840 		max = 3000000;
1841 		break;
1842 	default:
1843 		max = 2000000;
1844 		break;
1845 	}
1846 
1847 	priv->min_speed = min;
1848 	priv->max_speed = max;
1849 	priv->use_actual_rate = use_actual_rate;
1850 }
1851 
1852 static int cp210x_attach(struct usb_serial *serial)
1853 {
1854 	int result;
1855 	struct cp210x_serial_private *priv;
1856 
1857 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1858 	if (!priv)
1859 		return -ENOMEM;
1860 
1861 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1862 					  CP210X_GET_PARTNUM, &priv->partnum,
1863 					  sizeof(priv->partnum));
1864 	if (result < 0) {
1865 		dev_warn(&serial->interface->dev,
1866 			 "querying part number failed\n");
1867 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1868 	}
1869 
1870 	usb_set_serial_data(serial, priv);
1871 
1872 	cp210x_init_max_speed(serial);
1873 
1874 	result = cp210x_gpio_init(serial);
1875 	if (result < 0) {
1876 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1877 				result);
1878 	}
1879 
1880 	return 0;
1881 }
1882 
1883 static void cp210x_disconnect(struct usb_serial *serial)
1884 {
1885 	cp210x_gpio_remove(serial);
1886 }
1887 
1888 static void cp210x_release(struct usb_serial *serial)
1889 {
1890 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1891 
1892 	cp210x_gpio_remove(serial);
1893 
1894 	kfree(priv);
1895 }
1896 
1897 module_usb_serial_driver(serial_drivers, id_table);
1898 
1899 MODULE_DESCRIPTION(DRIVER_DESC);
1900 MODULE_LICENSE("GPL v2");
1901