xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 55fd7e02)
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, 0x83AA) }, /* Mark-10 Digital Force Gauge */
129 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
130 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
131 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
132 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
133 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
134 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
135 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
136 	{ USB_DEVICE(0x10C4, 0x851E) }, /* CESINEL MEDCAL PT Network Analyzer */
137 	{ USB_DEVICE(0x10C4, 0x85A7) }, /* LifeScan OneTouch Verio IQ */
138 	{ USB_DEVICE(0x10C4, 0x85B8) }, /* CESINEL ReCon T Energy Logger */
139 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
140 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
141 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
142 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
143 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
144 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
145 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
146 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
147 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
148 	{ USB_DEVICE(0x10C4, 0x88FB) }, /* CESINEL MEDCAL STII Network Analyzer */
149 	{ USB_DEVICE(0x10C4, 0x8938) }, /* CESINEL MEDCAL S II Network Analyzer */
150 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
151 	{ USB_DEVICE(0x10C4, 0x8962) }, /* Brim Brothers charging dock */
152 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
153 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
154 	{ USB_DEVICE(0x10C4, 0x89A4) }, /* CESINEL FTBC Flexible Thyristor Bridge Controller */
155 	{ USB_DEVICE(0x10C4, 0x89FB) }, /* Qivicon ZigBee USB Radio Stick */
156 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
157 	{ USB_DEVICE(0x10C4, 0x8A5E) }, /* CEL EM3588 ZigBee USB Stick Long Range */
158 	{ USB_DEVICE(0x10C4, 0x8B34) }, /* Qivicon ZigBee USB Radio Stick */
159 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
160 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
161 	{ USB_DEVICE(0x10C4, 0xEA63) }, /* Silicon Labs Windows Update (CP2101-4/CP2102N) */
162 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
163 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
164 	{ USB_DEVICE(0x10C4, 0xEA7A) }, /* Silicon Labs Windows Update (CP2105) */
165 	{ USB_DEVICE(0x10C4, 0xEA7B) }, /* Silicon Labs Windows Update (CP2108) */
166 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
167 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
168 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
169 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
170 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
171 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
172 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
173 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
174 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
175 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
176 	{ USB_DEVICE(0x155A, 0x1006) },	/* ELDAT Easywave RX09 */
177 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
178 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
179 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
180 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
181 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
182 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
183 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
184 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
185 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
186 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
187 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
188 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
189 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
190 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
191 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
192 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
193 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
194 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
195 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
196 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
197 	{ USB_DEVICE(0x18EF, 0xE030) }, /* ELV ALC 8xxx Battery Charger */
198 	{ USB_DEVICE(0x18EF, 0xE032) }, /* ELV TFD500 Data Logger */
199 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
200 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
201 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
202 	{ USB_DEVICE(0x1901, 0x0195) },	/* GE B850/B650/B450 CP2104 DP UART interface */
203 	{ USB_DEVICE(0x1901, 0x0196) },	/* GE B850 CP2105 DP UART interface */
204 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
205 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
206 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
207 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
208 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
209 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
210 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
211 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
212 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
213 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
214 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
215 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
216 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
217 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
218 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
219 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
220 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
221 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
222 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
223 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
224 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
225 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
226 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
227 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
228 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
229 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
230 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
231 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
232 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
233 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
234 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
235 	{ USB_DEVICE(0x3923, 0x7A0B) }, /* National Instruments USB Serial Console */
236 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
237 	{ } /* Terminating Entry */
238 };
239 
240 MODULE_DEVICE_TABLE(usb, id_table);
241 
242 struct cp210x_serial_private {
243 #ifdef CONFIG_GPIOLIB
244 	struct gpio_chip	gc;
245 	bool			gpio_registered;
246 	u8			gpio_pushpull;
247 	u8			gpio_altfunc;
248 	u8			gpio_input;
249 #endif
250 	u8			partnum;
251 	speed_t			min_speed;
252 	speed_t			max_speed;
253 	bool			use_actual_rate;
254 };
255 
256 struct cp210x_port_private {
257 	__u8			bInterfaceNumber;
258 	bool			has_swapped_line_ctl;
259 };
260 
261 static struct usb_serial_driver cp210x_device = {
262 	.driver = {
263 		.owner =	THIS_MODULE,
264 		.name =		"cp210x",
265 	},
266 	.id_table		= id_table,
267 	.num_ports		= 1,
268 	.bulk_in_size		= 256,
269 	.bulk_out_size		= 256,
270 	.open			= cp210x_open,
271 	.close			= cp210x_close,
272 	.break_ctl		= cp210x_break_ctl,
273 	.set_termios		= cp210x_set_termios,
274 	.tx_empty		= cp210x_tx_empty,
275 	.tiocmget		= cp210x_tiocmget,
276 	.tiocmset		= cp210x_tiocmset,
277 	.attach			= cp210x_attach,
278 	.disconnect		= cp210x_disconnect,
279 	.release		= cp210x_release,
280 	.port_probe		= cp210x_port_probe,
281 	.port_remove		= cp210x_port_remove,
282 	.dtr_rts		= cp210x_dtr_rts
283 };
284 
285 static struct usb_serial_driver * const serial_drivers[] = {
286 	&cp210x_device, NULL
287 };
288 
289 /* Config request types */
290 #define REQTYPE_HOST_TO_INTERFACE	0x41
291 #define REQTYPE_INTERFACE_TO_HOST	0xc1
292 #define REQTYPE_HOST_TO_DEVICE	0x40
293 #define REQTYPE_DEVICE_TO_HOST	0xc0
294 
295 /* Config request codes */
296 #define CP210X_IFC_ENABLE	0x00
297 #define CP210X_SET_BAUDDIV	0x01
298 #define CP210X_GET_BAUDDIV	0x02
299 #define CP210X_SET_LINE_CTL	0x03
300 #define CP210X_GET_LINE_CTL	0x04
301 #define CP210X_SET_BREAK	0x05
302 #define CP210X_IMM_CHAR		0x06
303 #define CP210X_SET_MHS		0x07
304 #define CP210X_GET_MDMSTS	0x08
305 #define CP210X_SET_XON		0x09
306 #define CP210X_SET_XOFF		0x0A
307 #define CP210X_SET_EVENTMASK	0x0B
308 #define CP210X_GET_EVENTMASK	0x0C
309 #define CP210X_SET_CHAR		0x0D
310 #define CP210X_GET_CHARS	0x0E
311 #define CP210X_GET_PROPS	0x0F
312 #define CP210X_GET_COMM_STATUS	0x10
313 #define CP210X_RESET		0x11
314 #define CP210X_PURGE		0x12
315 #define CP210X_SET_FLOW		0x13
316 #define CP210X_GET_FLOW		0x14
317 #define CP210X_EMBED_EVENTS	0x15
318 #define CP210X_GET_EVENTSTATE	0x16
319 #define CP210X_SET_CHARS	0x19
320 #define CP210X_GET_BAUDRATE	0x1D
321 #define CP210X_SET_BAUDRATE	0x1E
322 #define CP210X_VENDOR_SPECIFIC	0xFF
323 
324 /* CP210X_IFC_ENABLE */
325 #define UART_ENABLE		0x0001
326 #define UART_DISABLE		0x0000
327 
328 /* CP210X_(SET|GET)_BAUDDIV */
329 #define BAUD_RATE_GEN_FREQ	0x384000
330 
331 /* CP210X_(SET|GET)_LINE_CTL */
332 #define BITS_DATA_MASK		0X0f00
333 #define BITS_DATA_5		0X0500
334 #define BITS_DATA_6		0X0600
335 #define BITS_DATA_7		0X0700
336 #define BITS_DATA_8		0X0800
337 #define BITS_DATA_9		0X0900
338 
339 #define BITS_PARITY_MASK	0x00f0
340 #define BITS_PARITY_NONE	0x0000
341 #define BITS_PARITY_ODD		0x0010
342 #define BITS_PARITY_EVEN	0x0020
343 #define BITS_PARITY_MARK	0x0030
344 #define BITS_PARITY_SPACE	0x0040
345 
346 #define BITS_STOP_MASK		0x000f
347 #define BITS_STOP_1		0x0000
348 #define BITS_STOP_1_5		0x0001
349 #define BITS_STOP_2		0x0002
350 
351 /* CP210X_SET_BREAK */
352 #define BREAK_ON		0x0001
353 #define BREAK_OFF		0x0000
354 
355 /* CP210X_(SET_MHS|GET_MDMSTS) */
356 #define CONTROL_DTR		0x0001
357 #define CONTROL_RTS		0x0002
358 #define CONTROL_CTS		0x0010
359 #define CONTROL_DSR		0x0020
360 #define CONTROL_RING		0x0040
361 #define CONTROL_DCD		0x0080
362 #define CONTROL_WRITE_DTR	0x0100
363 #define CONTROL_WRITE_RTS	0x0200
364 
365 /* CP210X_VENDOR_SPECIFIC values */
366 #define CP210X_READ_2NCONFIG	0x000E
367 #define CP210X_READ_LATCH	0x00C2
368 #define CP210X_GET_PARTNUM	0x370B
369 #define CP210X_GET_PORTCONFIG	0x370C
370 #define CP210X_GET_DEVICEMODE	0x3711
371 #define CP210X_WRITE_LATCH	0x37E1
372 
373 /* Part number definitions */
374 #define CP210X_PARTNUM_CP2101	0x01
375 #define CP210X_PARTNUM_CP2102	0x02
376 #define CP210X_PARTNUM_CP2103	0x03
377 #define CP210X_PARTNUM_CP2104	0x04
378 #define CP210X_PARTNUM_CP2105	0x05
379 #define CP210X_PARTNUM_CP2108	0x08
380 #define CP210X_PARTNUM_CP2102N_QFN28	0x20
381 #define CP210X_PARTNUM_CP2102N_QFN24	0x21
382 #define CP210X_PARTNUM_CP2102N_QFN20	0x22
383 #define CP210X_PARTNUM_UNKNOWN	0xFF
384 
385 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
386 struct cp210x_comm_status {
387 	__le32   ulErrors;
388 	__le32   ulHoldReasons;
389 	__le32   ulAmountInInQueue;
390 	__le32   ulAmountInOutQueue;
391 	u8       bEofReceived;
392 	u8       bWaitForImmediate;
393 	u8       bReserved;
394 } __packed;
395 
396 /*
397  * CP210X_PURGE - 16 bits passed in wValue of USB request.
398  * SiLabs app note AN571 gives a strange description of the 4 bits:
399  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
400  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
401  */
402 #define PURGE_ALL		0x000f
403 
404 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
405 struct cp210x_flow_ctl {
406 	__le32	ulControlHandshake;
407 	__le32	ulFlowReplace;
408 	__le32	ulXonLimit;
409 	__le32	ulXoffLimit;
410 } __packed;
411 
412 /* cp210x_flow_ctl::ulControlHandshake */
413 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
414 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
415 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
416 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
417 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
418 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
419 
420 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
421 #define CP210X_SERIAL_DTR_INACTIVE	0
422 #define CP210X_SERIAL_DTR_ACTIVE	1
423 #define CP210X_SERIAL_DTR_FLOW_CTL	2
424 
425 /* cp210x_flow_ctl::ulFlowReplace */
426 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
427 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
428 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
429 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
430 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
431 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
432 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
433 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
434 
435 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
436 #define CP210X_SERIAL_RTS_INACTIVE	0
437 #define CP210X_SERIAL_RTS_ACTIVE	1
438 #define CP210X_SERIAL_RTS_FLOW_CTL	2
439 
440 /* CP210X_VENDOR_SPECIFIC, CP210X_GET_DEVICEMODE call reads these 0x2 bytes. */
441 struct cp210x_pin_mode {
442 	u8	eci;
443 	u8	sci;
444 } __packed;
445 
446 #define CP210X_PIN_MODE_MODEM		0
447 #define CP210X_PIN_MODE_GPIO		BIT(0)
448 
449 /*
450  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xf bytes
451  * on a CP2105 chip. Structure needs padding due to unused/unspecified bytes.
452  */
453 struct cp210x_dual_port_config {
454 	__le16	gpio_mode;
455 	u8	__pad0[2];
456 	__le16	reset_state;
457 	u8	__pad1[4];
458 	__le16	suspend_state;
459 	u8	sci_cfg;
460 	u8	eci_cfg;
461 	u8	device_cfg;
462 } __packed;
463 
464 /*
465  * CP210X_VENDOR_SPECIFIC, CP210X_GET_PORTCONFIG call reads these 0xd bytes
466  * on a CP2104 chip. Structure needs padding due to unused/unspecified bytes.
467  */
468 struct cp210x_single_port_config {
469 	__le16	gpio_mode;
470 	u8	__pad0[2];
471 	__le16	reset_state;
472 	u8	__pad1[4];
473 	__le16	suspend_state;
474 	u8	device_cfg;
475 } __packed;
476 
477 /* GPIO modes */
478 #define CP210X_SCI_GPIO_MODE_OFFSET	9
479 #define CP210X_SCI_GPIO_MODE_MASK	GENMASK(11, 9)
480 
481 #define CP210X_ECI_GPIO_MODE_OFFSET	2
482 #define CP210X_ECI_GPIO_MODE_MASK	GENMASK(3, 2)
483 
484 #define CP210X_GPIO_MODE_OFFSET		8
485 #define CP210X_GPIO_MODE_MASK		GENMASK(11, 8)
486 
487 /* CP2105 port configuration values */
488 #define CP2105_GPIO0_TXLED_MODE		BIT(0)
489 #define CP2105_GPIO1_RXLED_MODE		BIT(1)
490 #define CP2105_GPIO1_RS485_MODE		BIT(2)
491 
492 /* CP2104 port configuration values */
493 #define CP2104_GPIO0_TXLED_MODE		BIT(0)
494 #define CP2104_GPIO1_RXLED_MODE		BIT(1)
495 #define CP2104_GPIO2_RS485_MODE		BIT(2)
496 
497 /* CP2102N configuration array indices */
498 #define CP210X_2NCONFIG_CONFIG_VERSION_IDX	2
499 #define CP210X_2NCONFIG_GPIO_MODE_IDX		581
500 #define CP210X_2NCONFIG_GPIO_RSTLATCH_IDX	587
501 #define CP210X_2NCONFIG_GPIO_CONTROL_IDX	600
502 
503 /* CP210X_VENDOR_SPECIFIC, CP210X_WRITE_LATCH call writes these 0x2 bytes. */
504 struct cp210x_gpio_write {
505 	u8	mask;
506 	u8	state;
507 } __packed;
508 
509 /*
510  * Helper to get interface number when we only have struct usb_serial.
511  */
512 static u8 cp210x_interface_num(struct usb_serial *serial)
513 {
514 	struct usb_host_interface *cur_altsetting;
515 
516 	cur_altsetting = serial->interface->cur_altsetting;
517 
518 	return cur_altsetting->desc.bInterfaceNumber;
519 }
520 
521 /*
522  * Reads a variable-sized block of CP210X_ registers, identified by req.
523  * Returns data into buf in native USB byte order.
524  */
525 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
526 		void *buf, int bufsize)
527 {
528 	struct usb_serial *serial = port->serial;
529 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
530 	void *dmabuf;
531 	int result;
532 
533 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
534 	if (!dmabuf) {
535 		/*
536 		 * FIXME Some callers don't bother to check for error,
537 		 * at least give them consistent junk until they are fixed
538 		 */
539 		memset(buf, 0, bufsize);
540 		return -ENOMEM;
541 	}
542 
543 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
544 			req, REQTYPE_INTERFACE_TO_HOST, 0,
545 			port_priv->bInterfaceNumber, dmabuf, bufsize,
546 			USB_CTRL_SET_TIMEOUT);
547 	if (result == bufsize) {
548 		memcpy(buf, dmabuf, bufsize);
549 		result = 0;
550 	} else {
551 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
552 				req, bufsize, result);
553 		if (result >= 0)
554 			result = -EIO;
555 
556 		/*
557 		 * FIXME Some callers don't bother to check for error,
558 		 * at least give them consistent junk until they are fixed
559 		 */
560 		memset(buf, 0, bufsize);
561 	}
562 
563 	kfree(dmabuf);
564 
565 	return result;
566 }
567 
568 /*
569  * Reads any 32-bit CP210X_ register identified by req.
570  */
571 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
572 {
573 	__le32 le32_val;
574 	int err;
575 
576 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
577 	if (err) {
578 		/*
579 		 * FIXME Some callers don't bother to check for error,
580 		 * at least give them consistent junk until they are fixed
581 		 */
582 		*val = 0;
583 		return err;
584 	}
585 
586 	*val = le32_to_cpu(le32_val);
587 
588 	return 0;
589 }
590 
591 /*
592  * Reads any 16-bit CP210X_ register identified by req.
593  */
594 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
595 {
596 	__le16 le16_val;
597 	int err;
598 
599 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
600 	if (err)
601 		return err;
602 
603 	*val = le16_to_cpu(le16_val);
604 
605 	return 0;
606 }
607 
608 /*
609  * Reads any 8-bit CP210X_ register identified by req.
610  */
611 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
612 {
613 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
614 }
615 
616 /*
617  * Reads a variable-sized vendor block of CP210X_ registers, identified by val.
618  * Returns data into buf in native USB byte order.
619  */
620 static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
621 				    void *buf, int bufsize)
622 {
623 	void *dmabuf;
624 	int result;
625 
626 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
627 	if (!dmabuf)
628 		return -ENOMEM;
629 
630 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
631 				 CP210X_VENDOR_SPECIFIC, type, val,
632 				 cp210x_interface_num(serial), dmabuf, bufsize,
633 				 USB_CTRL_GET_TIMEOUT);
634 	if (result == bufsize) {
635 		memcpy(buf, dmabuf, bufsize);
636 		result = 0;
637 	} else {
638 		dev_err(&serial->interface->dev,
639 			"failed to get vendor val 0x%04x size %d: %d\n", val,
640 			bufsize, result);
641 		if (result >= 0)
642 			result = -EIO;
643 	}
644 
645 	kfree(dmabuf);
646 
647 	return result;
648 }
649 
650 /*
651  * Writes any 16-bit CP210X_ register (req) whose value is passed
652  * entirely in the wValue field of the USB request.
653  */
654 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
655 {
656 	struct usb_serial *serial = port->serial;
657 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
658 	int result;
659 
660 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
661 			req, REQTYPE_HOST_TO_INTERFACE, val,
662 			port_priv->bInterfaceNumber, NULL, 0,
663 			USB_CTRL_SET_TIMEOUT);
664 	if (result < 0) {
665 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
666 				req, result);
667 	}
668 
669 	return result;
670 }
671 
672 /*
673  * Writes a variable-sized block of CP210X_ registers, identified by req.
674  * Data in buf must be in native USB byte order.
675  */
676 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
677 		void *buf, int bufsize)
678 {
679 	struct usb_serial *serial = port->serial;
680 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
681 	void *dmabuf;
682 	int result;
683 
684 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
685 	if (!dmabuf)
686 		return -ENOMEM;
687 
688 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
689 			req, REQTYPE_HOST_TO_INTERFACE, 0,
690 			port_priv->bInterfaceNumber, dmabuf, bufsize,
691 			USB_CTRL_SET_TIMEOUT);
692 
693 	kfree(dmabuf);
694 
695 	if (result == bufsize) {
696 		result = 0;
697 	} else {
698 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
699 				req, bufsize, result);
700 		if (result >= 0)
701 			result = -EIO;
702 	}
703 
704 	return result;
705 }
706 
707 /*
708  * Writes any 32-bit CP210X_ register identified by req.
709  */
710 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
711 {
712 	__le32 le32_val;
713 
714 	le32_val = cpu_to_le32(val);
715 
716 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
717 }
718 
719 #ifdef CONFIG_GPIOLIB
720 /*
721  * Writes a variable-sized vendor block of CP210X_ registers, identified by val.
722  * Data in buf must be in native USB byte order.
723  */
724 static int cp210x_write_vendor_block(struct usb_serial *serial, u8 type,
725 				     u16 val, void *buf, int bufsize)
726 {
727 	void *dmabuf;
728 	int result;
729 
730 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
731 	if (!dmabuf)
732 		return -ENOMEM;
733 
734 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
735 				 CP210X_VENDOR_SPECIFIC, type, val,
736 				 cp210x_interface_num(serial), dmabuf, bufsize,
737 				 USB_CTRL_SET_TIMEOUT);
738 
739 	kfree(dmabuf);
740 
741 	if (result == bufsize) {
742 		result = 0;
743 	} else {
744 		dev_err(&serial->interface->dev,
745 			"failed to set vendor val 0x%04x size %d: %d\n", val,
746 			bufsize, result);
747 		if (result >= 0)
748 			result = -EIO;
749 	}
750 
751 	return result;
752 }
753 #endif
754 
755 /*
756  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
757  * Write a known good value 0x800, read it back.
758  * If it comes back swapped the bug is detected.
759  * Preserve the original register value.
760  */
761 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
762 {
763 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
764 	u16 line_ctl_save;
765 	u16 line_ctl_test;
766 	int err;
767 
768 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
769 	if (err)
770 		return err;
771 
772 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
773 	if (err)
774 		return err;
775 
776 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
777 	if (err)
778 		return err;
779 
780 	if (line_ctl_test == 8) {
781 		port_priv->has_swapped_line_ctl = true;
782 		line_ctl_save = swab16(line_ctl_save);
783 	}
784 
785 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
786 }
787 
788 /*
789  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
790  * to workaround cp2108 bug and get correct value.
791  */
792 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
793 {
794 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
795 	int err;
796 
797 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
798 	if (err)
799 		return err;
800 
801 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
802 	if (port_priv->has_swapped_line_ctl)
803 		*ctl = swab16(*ctl);
804 
805 	return 0;
806 }
807 
808 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
809 {
810 	int result;
811 
812 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
813 	if (result) {
814 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
815 		return result;
816 	}
817 
818 	/* Configure the termios structure */
819 	cp210x_get_termios(tty, port);
820 
821 	/* The baud rate must be initialised on cp2104 */
822 	if (tty)
823 		cp210x_change_speed(tty, port, NULL);
824 
825 	return usb_serial_generic_open(tty, port);
826 }
827 
828 static void cp210x_close(struct usb_serial_port *port)
829 {
830 	usb_serial_generic_close(port);
831 
832 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
833 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
834 
835 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
836 }
837 
838 /*
839  * Read how many bytes are waiting in the TX queue.
840  */
841 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
842 		u32 *count)
843 {
844 	struct usb_serial *serial = port->serial;
845 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
846 	struct cp210x_comm_status *sts;
847 	int result;
848 
849 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
850 	if (!sts)
851 		return -ENOMEM;
852 
853 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
854 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
855 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
856 			USB_CTRL_GET_TIMEOUT);
857 	if (result == sizeof(*sts)) {
858 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
859 		result = 0;
860 	} else {
861 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
862 		if (result >= 0)
863 			result = -EIO;
864 	}
865 
866 	kfree(sts);
867 
868 	return result;
869 }
870 
871 static bool cp210x_tx_empty(struct usb_serial_port *port)
872 {
873 	int err;
874 	u32 count;
875 
876 	err = cp210x_get_tx_queue_byte_count(port, &count);
877 	if (err)
878 		return true;
879 
880 	return !count;
881 }
882 
883 /*
884  * cp210x_get_termios
885  * Reads the baud rate, data bits, parity, stop bits and flow control mode
886  * from the device, corrects any unsupported values, and configures the
887  * termios structure to reflect the state of the device
888  */
889 static void cp210x_get_termios(struct tty_struct *tty,
890 	struct usb_serial_port *port)
891 {
892 	unsigned int baud;
893 
894 	if (tty) {
895 		cp210x_get_termios_port(tty->driver_data,
896 			&tty->termios.c_cflag, &baud);
897 		tty_encode_baud_rate(tty, baud, baud);
898 	} else {
899 		tcflag_t cflag;
900 		cflag = 0;
901 		cp210x_get_termios_port(port, &cflag, &baud);
902 	}
903 }
904 
905 /*
906  * cp210x_get_termios_port
907  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
908  */
909 static void cp210x_get_termios_port(struct usb_serial_port *port,
910 	tcflag_t *cflagp, unsigned int *baudp)
911 {
912 	struct device *dev = &port->dev;
913 	tcflag_t cflag;
914 	struct cp210x_flow_ctl flow_ctl;
915 	u32 baud;
916 	u16 bits;
917 	u32 ctl_hs;
918 
919 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
920 
921 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
922 	*baudp = baud;
923 
924 	cflag = *cflagp;
925 
926 	cp210x_get_line_ctl(port, &bits);
927 	cflag &= ~CSIZE;
928 	switch (bits & BITS_DATA_MASK) {
929 	case BITS_DATA_5:
930 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
931 		cflag |= CS5;
932 		break;
933 	case BITS_DATA_6:
934 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
935 		cflag |= CS6;
936 		break;
937 	case BITS_DATA_7:
938 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
939 		cflag |= CS7;
940 		break;
941 	case BITS_DATA_8:
942 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
943 		cflag |= CS8;
944 		break;
945 	case BITS_DATA_9:
946 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
947 		cflag |= CS8;
948 		bits &= ~BITS_DATA_MASK;
949 		bits |= BITS_DATA_8;
950 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
951 		break;
952 	default:
953 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
954 		cflag |= CS8;
955 		bits &= ~BITS_DATA_MASK;
956 		bits |= BITS_DATA_8;
957 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
958 		break;
959 	}
960 
961 	switch (bits & BITS_PARITY_MASK) {
962 	case BITS_PARITY_NONE:
963 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
964 		cflag &= ~PARENB;
965 		break;
966 	case BITS_PARITY_ODD:
967 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
968 		cflag |= (PARENB|PARODD);
969 		break;
970 	case BITS_PARITY_EVEN:
971 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
972 		cflag &= ~PARODD;
973 		cflag |= PARENB;
974 		break;
975 	case BITS_PARITY_MARK:
976 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
977 		cflag |= (PARENB|PARODD|CMSPAR);
978 		break;
979 	case BITS_PARITY_SPACE:
980 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
981 		cflag &= ~PARODD;
982 		cflag |= (PARENB|CMSPAR);
983 		break;
984 	default:
985 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
986 		cflag &= ~PARENB;
987 		bits &= ~BITS_PARITY_MASK;
988 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
989 		break;
990 	}
991 
992 	cflag &= ~CSTOPB;
993 	switch (bits & BITS_STOP_MASK) {
994 	case BITS_STOP_1:
995 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
996 		break;
997 	case BITS_STOP_1_5:
998 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
999 		bits &= ~BITS_STOP_MASK;
1000 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1001 		break;
1002 	case BITS_STOP_2:
1003 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1004 		cflag |= CSTOPB;
1005 		break;
1006 	default:
1007 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
1008 		bits &= ~BITS_STOP_MASK;
1009 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
1010 		break;
1011 	}
1012 
1013 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1014 			sizeof(flow_ctl));
1015 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1016 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1017 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1018 		cflag |= CRTSCTS;
1019 	} else {
1020 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1021 		cflag &= ~CRTSCTS;
1022 	}
1023 
1024 	*cflagp = cflag;
1025 }
1026 
1027 struct cp210x_rate {
1028 	speed_t rate;
1029 	speed_t high;
1030 };
1031 
1032 static const struct cp210x_rate cp210x_an205_table1[] = {
1033 	{ 300, 300 },
1034 	{ 600, 600 },
1035 	{ 1200, 1200 },
1036 	{ 1800, 1800 },
1037 	{ 2400, 2400 },
1038 	{ 4000, 4000 },
1039 	{ 4800, 4803 },
1040 	{ 7200, 7207 },
1041 	{ 9600, 9612 },
1042 	{ 14400, 14428 },
1043 	{ 16000, 16062 },
1044 	{ 19200, 19250 },
1045 	{ 28800, 28912 },
1046 	{ 38400, 38601 },
1047 	{ 51200, 51558 },
1048 	{ 56000, 56280 },
1049 	{ 57600, 58053 },
1050 	{ 64000, 64111 },
1051 	{ 76800, 77608 },
1052 	{ 115200, 117028 },
1053 	{ 128000, 129347 },
1054 	{ 153600, 156868 },
1055 	{ 230400, 237832 },
1056 	{ 250000, 254234 },
1057 	{ 256000, 273066 },
1058 	{ 460800, 491520 },
1059 	{ 500000, 567138 },
1060 	{ 576000, 670254 },
1061 	{ 921600, UINT_MAX }
1062 };
1063 
1064 /*
1065  * Quantises the baud rate as per AN205 Table 1
1066  */
1067 static speed_t cp210x_get_an205_rate(speed_t baud)
1068 {
1069 	int i;
1070 
1071 	for (i = 0; i < ARRAY_SIZE(cp210x_an205_table1); ++i) {
1072 		if (baud <= cp210x_an205_table1[i].high)
1073 			break;
1074 	}
1075 
1076 	return cp210x_an205_table1[i].rate;
1077 }
1078 
1079 static speed_t cp210x_get_actual_rate(speed_t baud)
1080 {
1081 	unsigned int prescale = 1;
1082 	unsigned int div;
1083 
1084 	if (baud <= 365)
1085 		prescale = 4;
1086 
1087 	div = DIV_ROUND_CLOSEST(48000000, 2 * prescale * baud);
1088 	baud = 48000000 / (2 * prescale * div);
1089 
1090 	return baud;
1091 }
1092 
1093 /*
1094  * CP2101 supports the following baud rates:
1095  *
1096  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1097  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1098  *
1099  * CP2102 and CP2103 support the following additional rates:
1100  *
1101  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1102  *	576000
1103  *
1104  * The device will map a requested rate to a supported one, but the result
1105  * of requests for rates greater than 1053257 is undefined (see AN205).
1106  *
1107  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1108  * respectively, with an error less than 1%. The actual rates are determined
1109  * by
1110  *
1111  *	div = round(freq / (2 x prescale x request))
1112  *	actual = freq / (2 x prescale x div)
1113  *
1114  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1115  * or 1 otherwise.
1116  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1117  * otherwise.
1118  */
1119 static void cp210x_change_speed(struct tty_struct *tty,
1120 		struct usb_serial_port *port, struct ktermios *old_termios)
1121 {
1122 	struct usb_serial *serial = port->serial;
1123 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1124 	u32 baud;
1125 
1126 	/*
1127 	 * This maps the requested rate to the actual rate, a valid rate on
1128 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
1129 	 *
1130 	 * NOTE: B0 is not implemented.
1131 	 */
1132 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
1133 
1134 	if (priv->use_actual_rate)
1135 		baud = cp210x_get_actual_rate(baud);
1136 	else if (baud < 1000000)
1137 		baud = cp210x_get_an205_rate(baud);
1138 
1139 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1140 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1141 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1142 		if (old_termios)
1143 			baud = old_termios->c_ospeed;
1144 		else
1145 			baud = 9600;
1146 	}
1147 
1148 	tty_encode_baud_rate(tty, baud, baud);
1149 }
1150 
1151 static void cp210x_set_termios(struct tty_struct *tty,
1152 		struct usb_serial_port *port, struct ktermios *old_termios)
1153 {
1154 	struct device *dev = &port->dev;
1155 	unsigned int cflag, old_cflag;
1156 	u16 bits;
1157 
1158 	cflag = tty->termios.c_cflag;
1159 	old_cflag = old_termios->c_cflag;
1160 
1161 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
1162 		cp210x_change_speed(tty, port, old_termios);
1163 
1164 	/* If the number of data bits is to be updated */
1165 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1166 		cp210x_get_line_ctl(port, &bits);
1167 		bits &= ~BITS_DATA_MASK;
1168 		switch (cflag & CSIZE) {
1169 		case CS5:
1170 			bits |= BITS_DATA_5;
1171 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
1172 			break;
1173 		case CS6:
1174 			bits |= BITS_DATA_6;
1175 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
1176 			break;
1177 		case CS7:
1178 			bits |= BITS_DATA_7;
1179 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
1180 			break;
1181 		case CS8:
1182 		default:
1183 			bits |= BITS_DATA_8;
1184 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
1185 			break;
1186 		}
1187 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1188 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
1189 	}
1190 
1191 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1192 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
1193 		cp210x_get_line_ctl(port, &bits);
1194 		bits &= ~BITS_PARITY_MASK;
1195 		if (cflag & PARENB) {
1196 			if (cflag & CMSPAR) {
1197 				if (cflag & PARODD) {
1198 					bits |= BITS_PARITY_MARK;
1199 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
1200 				} else {
1201 					bits |= BITS_PARITY_SPACE;
1202 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1203 				}
1204 			} else {
1205 				if (cflag & PARODD) {
1206 					bits |= BITS_PARITY_ODD;
1207 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
1208 				} else {
1209 					bits |= BITS_PARITY_EVEN;
1210 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1211 				}
1212 			}
1213 		}
1214 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1215 			dev_dbg(dev, "Parity mode not supported by device\n");
1216 	}
1217 
1218 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1219 		cp210x_get_line_ctl(port, &bits);
1220 		bits &= ~BITS_STOP_MASK;
1221 		if (cflag & CSTOPB) {
1222 			bits |= BITS_STOP_2;
1223 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1224 		} else {
1225 			bits |= BITS_STOP_1;
1226 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1227 		}
1228 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1229 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1230 	}
1231 
1232 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1233 		struct cp210x_flow_ctl flow_ctl;
1234 		u32 ctl_hs;
1235 		u32 flow_repl;
1236 
1237 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1238 				sizeof(flow_ctl));
1239 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1240 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1241 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1242 				__func__, ctl_hs, flow_repl);
1243 
1244 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1245 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1246 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1247 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1248 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1249 		if (cflag & CRTSCTS) {
1250 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1251 
1252 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1253 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1254 					CP210X_SERIAL_RTS_FLOW_CTL);
1255 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1256 		} else {
1257 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1258 
1259 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1260 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1261 					CP210X_SERIAL_RTS_ACTIVE);
1262 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1263 		}
1264 
1265 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1266 				__func__, ctl_hs, flow_repl);
1267 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1268 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1269 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1270 				sizeof(flow_ctl));
1271 	}
1272 
1273 }
1274 
1275 static int cp210x_tiocmset(struct tty_struct *tty,
1276 		unsigned int set, unsigned int clear)
1277 {
1278 	struct usb_serial_port *port = tty->driver_data;
1279 	return cp210x_tiocmset_port(port, set, clear);
1280 }
1281 
1282 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1283 		unsigned int set, unsigned int clear)
1284 {
1285 	u16 control = 0;
1286 
1287 	if (set & TIOCM_RTS) {
1288 		control |= CONTROL_RTS;
1289 		control |= CONTROL_WRITE_RTS;
1290 	}
1291 	if (set & TIOCM_DTR) {
1292 		control |= CONTROL_DTR;
1293 		control |= CONTROL_WRITE_DTR;
1294 	}
1295 	if (clear & TIOCM_RTS) {
1296 		control &= ~CONTROL_RTS;
1297 		control |= CONTROL_WRITE_RTS;
1298 	}
1299 	if (clear & TIOCM_DTR) {
1300 		control &= ~CONTROL_DTR;
1301 		control |= CONTROL_WRITE_DTR;
1302 	}
1303 
1304 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1305 
1306 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1307 }
1308 
1309 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1310 {
1311 	if (on)
1312 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1313 	else
1314 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1315 }
1316 
1317 static int cp210x_tiocmget(struct tty_struct *tty)
1318 {
1319 	struct usb_serial_port *port = tty->driver_data;
1320 	u8 control;
1321 	int result;
1322 
1323 	result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1324 	if (result)
1325 		return result;
1326 
1327 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1328 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1329 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1330 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1331 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1332 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1333 
1334 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1335 
1336 	return result;
1337 }
1338 
1339 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1340 {
1341 	struct usb_serial_port *port = tty->driver_data;
1342 	u16 state;
1343 
1344 	if (break_state == 0)
1345 		state = BREAK_OFF;
1346 	else
1347 		state = BREAK_ON;
1348 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1349 		state == BREAK_OFF ? "off" : "on");
1350 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1351 }
1352 
1353 #ifdef CONFIG_GPIOLIB
1354 static int cp210x_gpio_request(struct gpio_chip *gc, unsigned int offset)
1355 {
1356 	struct usb_serial *serial = gpiochip_get_data(gc);
1357 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1358 
1359 	if (priv->gpio_altfunc & BIT(offset))
1360 		return -ENODEV;
1361 
1362 	return 0;
1363 }
1364 
1365 static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
1366 {
1367 	struct usb_serial *serial = gpiochip_get_data(gc);
1368 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1369 	u8 req_type = REQTYPE_DEVICE_TO_HOST;
1370 	int result;
1371 	u8 buf;
1372 
1373 	if (priv->partnum == CP210X_PARTNUM_CP2105)
1374 		req_type = REQTYPE_INTERFACE_TO_HOST;
1375 
1376 	result = usb_autopm_get_interface(serial->interface);
1377 	if (result)
1378 		return result;
1379 
1380 	result = cp210x_read_vendor_block(serial, req_type,
1381 					  CP210X_READ_LATCH, &buf, sizeof(buf));
1382 	usb_autopm_put_interface(serial->interface);
1383 	if (result < 0)
1384 		return result;
1385 
1386 	return !!(buf & BIT(gpio));
1387 }
1388 
1389 static void cp210x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
1390 {
1391 	struct usb_serial *serial = gpiochip_get_data(gc);
1392 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1393 	struct cp210x_gpio_write buf;
1394 	int result;
1395 
1396 	if (value == 1)
1397 		buf.state = BIT(gpio);
1398 	else
1399 		buf.state = 0;
1400 
1401 	buf.mask = BIT(gpio);
1402 
1403 	result = usb_autopm_get_interface(serial->interface);
1404 	if (result)
1405 		goto out;
1406 
1407 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1408 		result = cp210x_write_vendor_block(serial,
1409 						   REQTYPE_HOST_TO_INTERFACE,
1410 						   CP210X_WRITE_LATCH, &buf,
1411 						   sizeof(buf));
1412 	} else {
1413 		u16 wIndex = buf.state << 8 | buf.mask;
1414 
1415 		result = usb_control_msg(serial->dev,
1416 					 usb_sndctrlpipe(serial->dev, 0),
1417 					 CP210X_VENDOR_SPECIFIC,
1418 					 REQTYPE_HOST_TO_DEVICE,
1419 					 CP210X_WRITE_LATCH,
1420 					 wIndex,
1421 					 NULL, 0, USB_CTRL_SET_TIMEOUT);
1422 	}
1423 
1424 	usb_autopm_put_interface(serial->interface);
1425 out:
1426 	if (result < 0) {
1427 		dev_err(&serial->interface->dev, "failed to set GPIO value: %d\n",
1428 				result);
1429 	}
1430 }
1431 
1432 static int cp210x_gpio_direction_get(struct gpio_chip *gc, unsigned int gpio)
1433 {
1434 	struct usb_serial *serial = gpiochip_get_data(gc);
1435 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1436 
1437 	return priv->gpio_input & BIT(gpio);
1438 }
1439 
1440 static int cp210x_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio)
1441 {
1442 	struct usb_serial *serial = gpiochip_get_data(gc);
1443 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1444 
1445 	if (priv->partnum == CP210X_PARTNUM_CP2105) {
1446 		/* hardware does not support an input mode */
1447 		return -ENOTSUPP;
1448 	}
1449 
1450 	/* push-pull pins cannot be changed to be inputs */
1451 	if (priv->gpio_pushpull & BIT(gpio))
1452 		return -EINVAL;
1453 
1454 	/* make sure to release pin if it is being driven low */
1455 	cp210x_gpio_set(gc, gpio, 1);
1456 
1457 	priv->gpio_input |= BIT(gpio);
1458 
1459 	return 0;
1460 }
1461 
1462 static int cp210x_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio,
1463 					int value)
1464 {
1465 	struct usb_serial *serial = gpiochip_get_data(gc);
1466 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1467 
1468 	priv->gpio_input &= ~BIT(gpio);
1469 	cp210x_gpio_set(gc, gpio, value);
1470 
1471 	return 0;
1472 }
1473 
1474 static int cp210x_gpio_set_config(struct gpio_chip *gc, unsigned int gpio,
1475 				  unsigned long config)
1476 {
1477 	struct usb_serial *serial = gpiochip_get_data(gc);
1478 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1479 	enum pin_config_param param = pinconf_to_config_param(config);
1480 
1481 	/* Succeed only if in correct mode (this can't be set at runtime) */
1482 	if ((param == PIN_CONFIG_DRIVE_PUSH_PULL) &&
1483 	    (priv->gpio_pushpull & BIT(gpio)))
1484 		return 0;
1485 
1486 	if ((param == PIN_CONFIG_DRIVE_OPEN_DRAIN) &&
1487 	    !(priv->gpio_pushpull & BIT(gpio)))
1488 		return 0;
1489 
1490 	return -ENOTSUPP;
1491 }
1492 
1493 /*
1494  * This function is for configuring GPIO using shared pins, where other signals
1495  * are made unavailable by configuring the use of GPIO. This is believed to be
1496  * only applicable to the cp2105 at this point, the other devices supported by
1497  * this driver that provide GPIO do so in a way that does not impact other
1498  * signals and are thus expected to have very different initialisation.
1499  */
1500 static int cp2105_gpioconf_init(struct usb_serial *serial)
1501 {
1502 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1503 	struct cp210x_pin_mode mode;
1504 	struct cp210x_dual_port_config config;
1505 	u8 intf_num = cp210x_interface_num(serial);
1506 	u8 iface_config;
1507 	int result;
1508 
1509 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1510 					  CP210X_GET_DEVICEMODE, &mode,
1511 					  sizeof(mode));
1512 	if (result < 0)
1513 		return result;
1514 
1515 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1516 					  CP210X_GET_PORTCONFIG, &config,
1517 					  sizeof(config));
1518 	if (result < 0)
1519 		return result;
1520 
1521 	/*  2 banks of GPIO - One for the pins taken from each serial port */
1522 	if (intf_num == 0) {
1523 		if (mode.eci == CP210X_PIN_MODE_MODEM) {
1524 			/* mark all GPIOs of this interface as reserved */
1525 			priv->gpio_altfunc = 0xff;
1526 			return 0;
1527 		}
1528 
1529 		iface_config = config.eci_cfg;
1530 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1531 						CP210X_ECI_GPIO_MODE_MASK) >>
1532 						CP210X_ECI_GPIO_MODE_OFFSET);
1533 		priv->gc.ngpio = 2;
1534 	} else if (intf_num == 1) {
1535 		if (mode.sci == CP210X_PIN_MODE_MODEM) {
1536 			/* mark all GPIOs of this interface as reserved */
1537 			priv->gpio_altfunc = 0xff;
1538 			return 0;
1539 		}
1540 
1541 		iface_config = config.sci_cfg;
1542 		priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1543 						CP210X_SCI_GPIO_MODE_MASK) >>
1544 						CP210X_SCI_GPIO_MODE_OFFSET);
1545 		priv->gc.ngpio = 3;
1546 	} else {
1547 		return -ENODEV;
1548 	}
1549 
1550 	/* mark all pins which are not in GPIO mode */
1551 	if (iface_config & CP2105_GPIO0_TXLED_MODE)	/* GPIO 0 */
1552 		priv->gpio_altfunc |= BIT(0);
1553 	if (iface_config & (CP2105_GPIO1_RXLED_MODE |	/* GPIO 1 */
1554 			CP2105_GPIO1_RS485_MODE))
1555 		priv->gpio_altfunc |= BIT(1);
1556 
1557 	/* driver implementation for CP2105 only supports outputs */
1558 	priv->gpio_input = 0;
1559 
1560 	return 0;
1561 }
1562 
1563 static int cp2104_gpioconf_init(struct usb_serial *serial)
1564 {
1565 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1566 	struct cp210x_single_port_config config;
1567 	u8 iface_config;
1568 	u8 gpio_latch;
1569 	int result;
1570 	u8 i;
1571 
1572 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1573 					  CP210X_GET_PORTCONFIG, &config,
1574 					  sizeof(config));
1575 	if (result < 0)
1576 		return result;
1577 
1578 	priv->gc.ngpio = 4;
1579 
1580 	iface_config = config.device_cfg;
1581 	priv->gpio_pushpull = (u8)((le16_to_cpu(config.gpio_mode) &
1582 					CP210X_GPIO_MODE_MASK) >>
1583 					CP210X_GPIO_MODE_OFFSET);
1584 	gpio_latch = (u8)((le16_to_cpu(config.reset_state) &
1585 					CP210X_GPIO_MODE_MASK) >>
1586 					CP210X_GPIO_MODE_OFFSET);
1587 
1588 	/* mark all pins which are not in GPIO mode */
1589 	if (iface_config & CP2104_GPIO0_TXLED_MODE)	/* GPIO 0 */
1590 		priv->gpio_altfunc |= BIT(0);
1591 	if (iface_config & CP2104_GPIO1_RXLED_MODE)	/* GPIO 1 */
1592 		priv->gpio_altfunc |= BIT(1);
1593 	if (iface_config & CP2104_GPIO2_RS485_MODE)	/* GPIO 2 */
1594 		priv->gpio_altfunc |= BIT(2);
1595 
1596 	/*
1597 	 * Like CP2102N, CP2104 has also no strict input and output pin
1598 	 * modes.
1599 	 * Do the same input mode emulation as CP2102N.
1600 	 */
1601 	for (i = 0; i < priv->gc.ngpio; ++i) {
1602 		/*
1603 		 * Set direction to "input" iff pin is open-drain and reset
1604 		 * value is 1.
1605 		 */
1606 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1607 			priv->gpio_input |= BIT(i);
1608 	}
1609 
1610 	return 0;
1611 }
1612 
1613 static int cp2102n_gpioconf_init(struct usb_serial *serial)
1614 {
1615 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1616 	const u16 config_size = 0x02a6;
1617 	u8 gpio_rst_latch;
1618 	u8 config_version;
1619 	u8 gpio_pushpull;
1620 	u8 *config_buf;
1621 	u8 gpio_latch;
1622 	u8 gpio_ctrl;
1623 	int result;
1624 	u8 i;
1625 
1626 	/*
1627 	 * Retrieve device configuration from the device.
1628 	 * The array received contains all customization settings done at the
1629 	 * factory/manufacturer. Format of the array is documented at the
1630 	 * time of writing at:
1631 	 * https://www.silabs.com/community/interface/knowledge-base.entry.html/2017/03/31/cp2102n_setconfig-xsfa
1632 	 */
1633 	config_buf = kmalloc(config_size, GFP_KERNEL);
1634 	if (!config_buf)
1635 		return -ENOMEM;
1636 
1637 	result = cp210x_read_vendor_block(serial,
1638 					  REQTYPE_DEVICE_TO_HOST,
1639 					  CP210X_READ_2NCONFIG,
1640 					  config_buf,
1641 					  config_size);
1642 	if (result < 0) {
1643 		kfree(config_buf);
1644 		return result;
1645 	}
1646 
1647 	config_version = config_buf[CP210X_2NCONFIG_CONFIG_VERSION_IDX];
1648 	gpio_pushpull = config_buf[CP210X_2NCONFIG_GPIO_MODE_IDX];
1649 	gpio_ctrl = config_buf[CP210X_2NCONFIG_GPIO_CONTROL_IDX];
1650 	gpio_rst_latch = config_buf[CP210X_2NCONFIG_GPIO_RSTLATCH_IDX];
1651 
1652 	kfree(config_buf);
1653 
1654 	/* Make sure this is a config format we understand. */
1655 	if (config_version != 0x01)
1656 		return -ENOTSUPP;
1657 
1658 	priv->gc.ngpio = 4;
1659 
1660 	/*
1661 	 * Get default pin states after reset. Needed so we can determine
1662 	 * the direction of an open-drain pin.
1663 	 */
1664 	gpio_latch = (gpio_rst_latch >> 3) & 0x0f;
1665 
1666 	/* 0 indicates open-drain mode, 1 is push-pull */
1667 	priv->gpio_pushpull = (gpio_pushpull >> 3) & 0x0f;
1668 
1669 	/* 0 indicates GPIO mode, 1 is alternate function */
1670 	priv->gpio_altfunc = (gpio_ctrl >> 2) & 0x0f;
1671 
1672 	if (priv->partnum == CP210X_PARTNUM_CP2102N_QFN28) {
1673 		/*
1674 		 * For the QFN28 package, GPIO4-6 are controlled by
1675 		 * the low three bits of the mode/latch fields.
1676 		 * Contrary to the document linked above, the bits for
1677 		 * the SUSPEND pins are elsewhere.  No alternate
1678 		 * function is available for these pins.
1679 		 */
1680 		priv->gc.ngpio = 7;
1681 		gpio_latch |= (gpio_rst_latch & 7) << 4;
1682 		priv->gpio_pushpull |= (gpio_pushpull & 7) << 4;
1683 	}
1684 
1685 	/*
1686 	 * The CP2102N does not strictly has input and output pin modes,
1687 	 * it only knows open-drain and push-pull modes which is set at
1688 	 * factory. An open-drain pin can function both as an
1689 	 * input or an output. We emulate input mode for open-drain pins
1690 	 * by making sure they are not driven low, and we do not allow
1691 	 * push-pull pins to be set as an input.
1692 	 */
1693 	for (i = 0; i < priv->gc.ngpio; ++i) {
1694 		/*
1695 		 * Set direction to "input" iff pin is open-drain and reset
1696 		 * value is 1.
1697 		 */
1698 		if (!(priv->gpio_pushpull & BIT(i)) && (gpio_latch & BIT(i)))
1699 			priv->gpio_input |= BIT(i);
1700 	}
1701 
1702 	return 0;
1703 }
1704 
1705 static int cp210x_gpio_init(struct usb_serial *serial)
1706 {
1707 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1708 	int result;
1709 
1710 	switch (priv->partnum) {
1711 	case CP210X_PARTNUM_CP2104:
1712 		result = cp2104_gpioconf_init(serial);
1713 		break;
1714 	case CP210X_PARTNUM_CP2105:
1715 		result = cp2105_gpioconf_init(serial);
1716 		break;
1717 	case CP210X_PARTNUM_CP2102N_QFN28:
1718 	case CP210X_PARTNUM_CP2102N_QFN24:
1719 	case CP210X_PARTNUM_CP2102N_QFN20:
1720 		result = cp2102n_gpioconf_init(serial);
1721 		break;
1722 	default:
1723 		return 0;
1724 	}
1725 
1726 	if (result < 0)
1727 		return result;
1728 
1729 	priv->gc.label = "cp210x";
1730 	priv->gc.request = cp210x_gpio_request;
1731 	priv->gc.get_direction = cp210x_gpio_direction_get;
1732 	priv->gc.direction_input = cp210x_gpio_direction_input;
1733 	priv->gc.direction_output = cp210x_gpio_direction_output;
1734 	priv->gc.get = cp210x_gpio_get;
1735 	priv->gc.set = cp210x_gpio_set;
1736 	priv->gc.set_config = cp210x_gpio_set_config;
1737 	priv->gc.owner = THIS_MODULE;
1738 	priv->gc.parent = &serial->interface->dev;
1739 	priv->gc.base = -1;
1740 	priv->gc.can_sleep = true;
1741 
1742 	result = gpiochip_add_data(&priv->gc, serial);
1743 	if (!result)
1744 		priv->gpio_registered = true;
1745 
1746 	return result;
1747 }
1748 
1749 static void cp210x_gpio_remove(struct usb_serial *serial)
1750 {
1751 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1752 
1753 	if (priv->gpio_registered) {
1754 		gpiochip_remove(&priv->gc);
1755 		priv->gpio_registered = false;
1756 	}
1757 }
1758 
1759 #else
1760 
1761 static int cp210x_gpio_init(struct usb_serial *serial)
1762 {
1763 	return 0;
1764 }
1765 
1766 static void cp210x_gpio_remove(struct usb_serial *serial)
1767 {
1768 	/* Nothing to do */
1769 }
1770 
1771 #endif
1772 
1773 static int cp210x_port_probe(struct usb_serial_port *port)
1774 {
1775 	struct usb_serial *serial = port->serial;
1776 	struct cp210x_port_private *port_priv;
1777 	int ret;
1778 
1779 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1780 	if (!port_priv)
1781 		return -ENOMEM;
1782 
1783 	port_priv->bInterfaceNumber = cp210x_interface_num(serial);
1784 
1785 	usb_set_serial_port_data(port, port_priv);
1786 
1787 	ret = cp210x_detect_swapped_line_ctl(port);
1788 	if (ret) {
1789 		kfree(port_priv);
1790 		return ret;
1791 	}
1792 
1793 	return 0;
1794 }
1795 
1796 static int cp210x_port_remove(struct usb_serial_port *port)
1797 {
1798 	struct cp210x_port_private *port_priv;
1799 
1800 	port_priv = usb_get_serial_port_data(port);
1801 	kfree(port_priv);
1802 
1803 	return 0;
1804 }
1805 
1806 static void cp210x_init_max_speed(struct usb_serial *serial)
1807 {
1808 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1809 	bool use_actual_rate = false;
1810 	speed_t min = 300;
1811 	speed_t max;
1812 
1813 	switch (priv->partnum) {
1814 	case CP210X_PARTNUM_CP2101:
1815 		max = 921600;
1816 		break;
1817 	case CP210X_PARTNUM_CP2102:
1818 	case CP210X_PARTNUM_CP2103:
1819 		max = 1000000;
1820 		break;
1821 	case CP210X_PARTNUM_CP2104:
1822 		use_actual_rate = true;
1823 		max = 2000000;
1824 		break;
1825 	case CP210X_PARTNUM_CP2108:
1826 		max = 2000000;
1827 		break;
1828 	case CP210X_PARTNUM_CP2105:
1829 		if (cp210x_interface_num(serial) == 0) {
1830 			use_actual_rate = true;
1831 			max = 2000000;	/* ECI */
1832 		} else {
1833 			min = 2400;
1834 			max = 921600;	/* SCI */
1835 		}
1836 		break;
1837 	case CP210X_PARTNUM_CP2102N_QFN28:
1838 	case CP210X_PARTNUM_CP2102N_QFN24:
1839 	case CP210X_PARTNUM_CP2102N_QFN20:
1840 		use_actual_rate = true;
1841 		max = 3000000;
1842 		break;
1843 	default:
1844 		max = 2000000;
1845 		break;
1846 	}
1847 
1848 	priv->min_speed = min;
1849 	priv->max_speed = max;
1850 	priv->use_actual_rate = use_actual_rate;
1851 }
1852 
1853 static int cp210x_attach(struct usb_serial *serial)
1854 {
1855 	int result;
1856 	struct cp210x_serial_private *priv;
1857 
1858 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1859 	if (!priv)
1860 		return -ENOMEM;
1861 
1862 	result = cp210x_read_vendor_block(serial, REQTYPE_DEVICE_TO_HOST,
1863 					  CP210X_GET_PARTNUM, &priv->partnum,
1864 					  sizeof(priv->partnum));
1865 	if (result < 0) {
1866 		dev_warn(&serial->interface->dev,
1867 			 "querying part number failed\n");
1868 		priv->partnum = CP210X_PARTNUM_UNKNOWN;
1869 	}
1870 
1871 	usb_set_serial_data(serial, priv);
1872 
1873 	cp210x_init_max_speed(serial);
1874 
1875 	result = cp210x_gpio_init(serial);
1876 	if (result < 0) {
1877 		dev_err(&serial->interface->dev, "GPIO initialisation failed: %d\n",
1878 				result);
1879 	}
1880 
1881 	return 0;
1882 }
1883 
1884 static void cp210x_disconnect(struct usb_serial *serial)
1885 {
1886 	cp210x_gpio_remove(serial);
1887 }
1888 
1889 static void cp210x_release(struct usb_serial *serial)
1890 {
1891 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
1892 
1893 	cp210x_gpio_remove(serial);
1894 
1895 	kfree(priv);
1896 }
1897 
1898 module_usb_serial_driver(serial_drivers, id_table);
1899 
1900 MODULE_DESCRIPTION(DRIVER_DESC);
1901 MODULE_LICENSE("GPL v2");
1902