xref: /openbmc/linux/drivers/usb/serial/cp210x.c (revision 2d96b44f)
1 /*
2  * Silicon Laboratories CP210x USB to RS232 serial adaptor driver
3  *
4  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License version
8  *	2 as published by the Free Software Foundation.
9  *
10  * Support to set flow control line levels using TIOCMGET and TIOCMSET
11  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
12  * control thanks to Munir Nassar nassarmu@real-time.com
13  *
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <linux/tty.h>
20 #include <linux/tty_flip.h>
21 #include <linux/module.h>
22 #include <linux/moduleparam.h>
23 #include <linux/usb.h>
24 #include <linux/uaccess.h>
25 #include <linux/usb/serial.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 	unsigned int *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_port_probe(struct usb_serial_port *);
48 static int cp210x_port_remove(struct usb_serial_port *);
49 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
50 
51 static const struct usb_device_id id_table[] = {
52 	{ USB_DEVICE(0x045B, 0x0053) }, /* Renesas RX610 RX-Stick */
53 	{ USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
54 	{ USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
55 	{ USB_DEVICE(0x0489, 0xE003) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
56 	{ USB_DEVICE(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
57 	{ USB_DEVICE(0x0846, 0x1100) }, /* NetGear Managed Switch M4100 series, M5300 series, M7100 series */
58 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
59 	{ USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
60 	{ USB_DEVICE(0x0908, 0x01FF) }, /* Siemens RUGGEDCOM USB Serial Console */
61 	{ USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
62 	{ USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
63 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
64 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
65 	{ USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
66 	{ USB_DEVICE(0x0FDE, 0xCA05) }, /* OWL Wireless Electricity Monitor CM-160 */
67 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
68 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
69 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
70 	{ USB_DEVICE(0x10C4, 0x0F91) }, /* Vstabi */
71 	{ USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
72 	{ USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
73 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
74 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
75 	{ USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
76 	{ USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
77 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
78 	{ USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
79 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
80 	{ USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
81 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
82 	{ USB_DEVICE(0x10C4, 0x80C4) }, /* Cygnal Integrated Products, Inc., Optris infrared thermometer */
83 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
84 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
85 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
86 	{ USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
87 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
88 	{ USB_DEVICE(0x10C4, 0x813F) }, /* Tams Master Easy Control */
89 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
90 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
91 	{ USB_DEVICE(0x2405, 0x0003) }, /* West Mountain Radio RIGblaster Advantage */
92 	{ USB_DEVICE(0x10C4, 0x8156) }, /* B&G H3000 link cable */
93 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
94 	{ USB_DEVICE(0x10C4, 0x815F) }, /* Timewave HamLinkUSB */
95 	{ USB_DEVICE(0x10C4, 0x818B) }, /* AVIT Research USB to TTL */
96 	{ USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
97 	{ USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
98 	{ USB_DEVICE(0x10C4, 0x81A9) }, /* Multiplex RC Interface */
99 	{ USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
100 	{ USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
101 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
102 	{ USB_DEVICE(0x10C4, 0x81D7) }, /* IAI Corp. RCB-CV-USB USB to RS485 Adaptor */
103 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
104 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
105 	{ USB_DEVICE(0x10C4, 0x81E8) }, /* Zephyr Bioharness */
106 	{ USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
107 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
108 	{ USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
109 	{ USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demonstration module */
110 	{ USB_DEVICE(0x10C4, 0x8281) }, /* Nanotec Plug & Drive */
111 	{ USB_DEVICE(0x10C4, 0x8293) }, /* Telegesis ETRX2USB */
112 	{ USB_DEVICE(0x10C4, 0x82F4) }, /* Starizona MicroTouch */
113 	{ USB_DEVICE(0x10C4, 0x82F9) }, /* Procyon AVS */
114 	{ USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
115 	{ USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
116 	{ USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
117 	{ USB_DEVICE(0x10C4, 0x83D8) }, /* DekTec DTA Plus VHF/UHF Booster/Attenuator */
118 	{ USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
119 	{ USB_DEVICE(0x10C4, 0x8418) }, /* IRZ Automation Teleport SG-10 GSM/GPRS Modem */
120 	{ USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
121 	{ USB_DEVICE(0x10C4, 0x8470) }, /* Juniper Networks BX Series System Console */
122 	{ USB_DEVICE(0x10C4, 0x8477) }, /* Balluff RFID */
123 	{ USB_DEVICE(0x10C4, 0x84B6) }, /* Starizona Hyperion */
124 	{ USB_DEVICE(0x10C4, 0x85EA) }, /* AC-Services IBUS-IF */
125 	{ USB_DEVICE(0x10C4, 0x85EB) }, /* AC-Services CIS-IBUS */
126 	{ USB_DEVICE(0x10C4, 0x85F8) }, /* Virtenio Preon32 */
127 	{ USB_DEVICE(0x10C4, 0x8664) }, /* AC-Services CAN-IF */
128 	{ USB_DEVICE(0x10C4, 0x8665) }, /* AC-Services OBD-IF */
129 	{ USB_DEVICE(0x10C4, 0x8856) },	/* CEL EM357 ZigBee USB Stick - LR */
130 	{ USB_DEVICE(0x10C4, 0x8857) },	/* CEL EM357 ZigBee USB Stick */
131 	{ USB_DEVICE(0x10C4, 0x88A4) }, /* MMB Networks ZigBee USB Device */
132 	{ USB_DEVICE(0x10C4, 0x88A5) }, /* Planet Innovation Ingeni ZigBee USB Device */
133 	{ USB_DEVICE(0x10C4, 0x8946) }, /* Ketra N1 Wireless Interface */
134 	{ USB_DEVICE(0x10C4, 0x8977) },	/* CEL MeshWorks DevKit Device */
135 	{ USB_DEVICE(0x10C4, 0x8998) }, /* KCF Technologies PRN */
136 	{ USB_DEVICE(0x10C4, 0x8A2A) }, /* HubZ dual ZigBee and Z-Wave dongle */
137 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
138 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
139 	{ USB_DEVICE(0x10C4, 0xEA70) }, /* Silicon Labs factory default */
140 	{ USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
141 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
142 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
143 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
144 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
145 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
146 	{ USB_DEVICE(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
147 	{ USB_DEVICE(0x12B8, 0xEC60) }, /* Link G4 ECU */
148 	{ USB_DEVICE(0x12B8, 0xEC62) }, /* Link G4+ ECU */
149 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
150 	{ USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
151 	{ USB_DEVICE(0x166A, 0x0201) }, /* Clipsal 5500PACA C-Bus Pascal Automation Controller */
152 	{ USB_DEVICE(0x166A, 0x0301) }, /* Clipsal 5800PC C-Bus Wireless PC Interface */
153 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
154 	{ USB_DEVICE(0x166A, 0x0304) }, /* Clipsal 5000CT2 C-Bus Black and White Touchscreen */
155 	{ USB_DEVICE(0x166A, 0x0305) }, /* Clipsal C-5000CT2 C-Bus Spectrum Colour Touchscreen */
156 	{ USB_DEVICE(0x166A, 0x0401) }, /* Clipsal L51xx C-Bus Architectural Dimmer */
157 	{ USB_DEVICE(0x166A, 0x0101) }, /* Clipsal 5560884 C-Bus Multi-room Audio Matrix Switcher */
158 	{ USB_DEVICE(0x16C0, 0x09B0) }, /* Lunatico Seletek */
159 	{ USB_DEVICE(0x16C0, 0x09B1) }, /* Lunatico Seletek */
160 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
161 	{ USB_DEVICE(0x16DC, 0x0010) }, /* W-IE-NE-R Plein & Baus GmbH PL512 Power Supply */
162 	{ USB_DEVICE(0x16DC, 0x0011) }, /* W-IE-NE-R Plein & Baus GmbH RCM Remote Control for MARATON Power Supply */
163 	{ USB_DEVICE(0x16DC, 0x0012) }, /* W-IE-NE-R Plein & Baus GmbH MPOD Multi Channel Power Supply */
164 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
165 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
166 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
167 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
168 	{ USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
169 	{ USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
170 	{ USB_DEVICE(0x18EF, 0xE025) }, /* ELV Marble Sound Board 1 */
171 	{ USB_DEVICE(0x1901, 0x0190) }, /* GE B850 CP2105 Recorder interface */
172 	{ USB_DEVICE(0x1901, 0x0193) }, /* GE B650 CP2104 PMC interface */
173 	{ USB_DEVICE(0x1901, 0x0194) },	/* GE Healthcare Remote Alarm Box */
174 	{ USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */
175 	{ USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */
176 	{ USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */
177 	{ USB_DEVICE(0x1BA4, 0x0002) },	/* Silicon Labs 358x factory default */
178 	{ USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */
179 	{ USB_DEVICE(0x1D6F, 0x0010) }, /* Seluxit ApS RF Dongle */
180 	{ USB_DEVICE(0x1E29, 0x0102) }, /* Festo CPX-USB */
181 	{ USB_DEVICE(0x1E29, 0x0501) }, /* Festo CMSP */
182 	{ USB_DEVICE(0x1FB9, 0x0100) }, /* Lake Shore Model 121 Current Source */
183 	{ USB_DEVICE(0x1FB9, 0x0200) }, /* Lake Shore Model 218A Temperature Monitor */
184 	{ USB_DEVICE(0x1FB9, 0x0201) }, /* Lake Shore Model 219 Temperature Monitor */
185 	{ USB_DEVICE(0x1FB9, 0x0202) }, /* Lake Shore Model 233 Temperature Transmitter */
186 	{ USB_DEVICE(0x1FB9, 0x0203) }, /* Lake Shore Model 235 Temperature Transmitter */
187 	{ USB_DEVICE(0x1FB9, 0x0300) }, /* Lake Shore Model 335 Temperature Controller */
188 	{ USB_DEVICE(0x1FB9, 0x0301) }, /* Lake Shore Model 336 Temperature Controller */
189 	{ USB_DEVICE(0x1FB9, 0x0302) }, /* Lake Shore Model 350 Temperature Controller */
190 	{ USB_DEVICE(0x1FB9, 0x0303) }, /* Lake Shore Model 371 AC Bridge */
191 	{ USB_DEVICE(0x1FB9, 0x0400) }, /* Lake Shore Model 411 Handheld Gaussmeter */
192 	{ USB_DEVICE(0x1FB9, 0x0401) }, /* Lake Shore Model 425 Gaussmeter */
193 	{ USB_DEVICE(0x1FB9, 0x0402) }, /* Lake Shore Model 455A Gaussmeter */
194 	{ USB_DEVICE(0x1FB9, 0x0403) }, /* Lake Shore Model 475A Gaussmeter */
195 	{ USB_DEVICE(0x1FB9, 0x0404) }, /* Lake Shore Model 465 Three Axis Gaussmeter */
196 	{ USB_DEVICE(0x1FB9, 0x0600) }, /* Lake Shore Model 625A Superconducting MPS */
197 	{ USB_DEVICE(0x1FB9, 0x0601) }, /* Lake Shore Model 642A Magnet Power Supply */
198 	{ USB_DEVICE(0x1FB9, 0x0602) }, /* Lake Shore Model 648 Magnet Power Supply */
199 	{ USB_DEVICE(0x1FB9, 0x0700) }, /* Lake Shore Model 737 VSM Controller */
200 	{ USB_DEVICE(0x1FB9, 0x0701) }, /* Lake Shore Model 776 Hall Matrix */
201 	{ USB_DEVICE(0x2626, 0xEA60) }, /* Aruba Networks 7xxx USB Serial Console */
202 	{ USB_DEVICE(0x3195, 0xF190) }, /* Link Instruments MSO-19 */
203 	{ USB_DEVICE(0x3195, 0xF280) }, /* Link Instruments MSO-28 */
204 	{ USB_DEVICE(0x3195, 0xF281) }, /* Link Instruments MSO-28 */
205 	{ USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
206 	{ } /* Terminating Entry */
207 };
208 
209 MODULE_DEVICE_TABLE(usb, id_table);
210 
211 struct cp210x_port_private {
212 	__u8			bInterfaceNumber;
213 	bool			has_swapped_line_ctl;
214 };
215 
216 static struct usb_serial_driver cp210x_device = {
217 	.driver = {
218 		.owner =	THIS_MODULE,
219 		.name =		"cp210x",
220 	},
221 	.id_table		= id_table,
222 	.num_ports		= 1,
223 	.bulk_in_size		= 256,
224 	.bulk_out_size		= 256,
225 	.open			= cp210x_open,
226 	.close			= cp210x_close,
227 	.break_ctl		= cp210x_break_ctl,
228 	.set_termios		= cp210x_set_termios,
229 	.tx_empty		= cp210x_tx_empty,
230 	.tiocmget		= cp210x_tiocmget,
231 	.tiocmset		= cp210x_tiocmset,
232 	.port_probe		= cp210x_port_probe,
233 	.port_remove		= cp210x_port_remove,
234 	.dtr_rts		= cp210x_dtr_rts
235 };
236 
237 static struct usb_serial_driver * const serial_drivers[] = {
238 	&cp210x_device, NULL
239 };
240 
241 /* Config request types */
242 #define REQTYPE_HOST_TO_INTERFACE	0x41
243 #define REQTYPE_INTERFACE_TO_HOST	0xc1
244 #define REQTYPE_HOST_TO_DEVICE	0x40
245 #define REQTYPE_DEVICE_TO_HOST	0xc0
246 
247 /* Config request codes */
248 #define CP210X_IFC_ENABLE	0x00
249 #define CP210X_SET_BAUDDIV	0x01
250 #define CP210X_GET_BAUDDIV	0x02
251 #define CP210X_SET_LINE_CTL	0x03
252 #define CP210X_GET_LINE_CTL	0x04
253 #define CP210X_SET_BREAK	0x05
254 #define CP210X_IMM_CHAR		0x06
255 #define CP210X_SET_MHS		0x07
256 #define CP210X_GET_MDMSTS	0x08
257 #define CP210X_SET_XON		0x09
258 #define CP210X_SET_XOFF		0x0A
259 #define CP210X_SET_EVENTMASK	0x0B
260 #define CP210X_GET_EVENTMASK	0x0C
261 #define CP210X_SET_CHAR		0x0D
262 #define CP210X_GET_CHARS	0x0E
263 #define CP210X_GET_PROPS	0x0F
264 #define CP210X_GET_COMM_STATUS	0x10
265 #define CP210X_RESET		0x11
266 #define CP210X_PURGE		0x12
267 #define CP210X_SET_FLOW		0x13
268 #define CP210X_GET_FLOW		0x14
269 #define CP210X_EMBED_EVENTS	0x15
270 #define CP210X_GET_EVENTSTATE	0x16
271 #define CP210X_SET_CHARS	0x19
272 #define CP210X_GET_BAUDRATE	0x1D
273 #define CP210X_SET_BAUDRATE	0x1E
274 
275 /* CP210X_IFC_ENABLE */
276 #define UART_ENABLE		0x0001
277 #define UART_DISABLE		0x0000
278 
279 /* CP210X_(SET|GET)_BAUDDIV */
280 #define BAUD_RATE_GEN_FREQ	0x384000
281 
282 /* CP210X_(SET|GET)_LINE_CTL */
283 #define BITS_DATA_MASK		0X0f00
284 #define BITS_DATA_5		0X0500
285 #define BITS_DATA_6		0X0600
286 #define BITS_DATA_7		0X0700
287 #define BITS_DATA_8		0X0800
288 #define BITS_DATA_9		0X0900
289 
290 #define BITS_PARITY_MASK	0x00f0
291 #define BITS_PARITY_NONE	0x0000
292 #define BITS_PARITY_ODD		0x0010
293 #define BITS_PARITY_EVEN	0x0020
294 #define BITS_PARITY_MARK	0x0030
295 #define BITS_PARITY_SPACE	0x0040
296 
297 #define BITS_STOP_MASK		0x000f
298 #define BITS_STOP_1		0x0000
299 #define BITS_STOP_1_5		0x0001
300 #define BITS_STOP_2		0x0002
301 
302 /* CP210X_SET_BREAK */
303 #define BREAK_ON		0x0001
304 #define BREAK_OFF		0x0000
305 
306 /* CP210X_(SET_MHS|GET_MDMSTS) */
307 #define CONTROL_DTR		0x0001
308 #define CONTROL_RTS		0x0002
309 #define CONTROL_CTS		0x0010
310 #define CONTROL_DSR		0x0020
311 #define CONTROL_RING		0x0040
312 #define CONTROL_DCD		0x0080
313 #define CONTROL_WRITE_DTR	0x0100
314 #define CONTROL_WRITE_RTS	0x0200
315 
316 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
317 struct cp210x_comm_status {
318 	__le32   ulErrors;
319 	__le32   ulHoldReasons;
320 	__le32   ulAmountInInQueue;
321 	__le32   ulAmountInOutQueue;
322 	u8       bEofReceived;
323 	u8       bWaitForImmediate;
324 	u8       bReserved;
325 } __packed;
326 
327 /*
328  * CP210X_PURGE - 16 bits passed in wValue of USB request.
329  * SiLabs app note AN571 gives a strange description of the 4 bits:
330  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
331  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
332  */
333 #define PURGE_ALL		0x000f
334 
335 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
336 struct cp210x_flow_ctl {
337 	__le32	ulControlHandshake;
338 	__le32	ulFlowReplace;
339 	__le32	ulXonLimit;
340 	__le32	ulXoffLimit;
341 } __packed;
342 
343 /* cp210x_flow_ctl::ulControlHandshake */
344 #define CP210X_SERIAL_DTR_MASK		GENMASK(1, 0)
345 #define CP210X_SERIAL_DTR_SHIFT(_mode)	(_mode)
346 #define CP210X_SERIAL_CTS_HANDSHAKE	BIT(3)
347 #define CP210X_SERIAL_DSR_HANDSHAKE	BIT(4)
348 #define CP210X_SERIAL_DCD_HANDSHAKE	BIT(5)
349 #define CP210X_SERIAL_DSR_SENSITIVITY	BIT(6)
350 
351 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
352 #define CP210X_SERIAL_DTR_INACTIVE	0
353 #define CP210X_SERIAL_DTR_ACTIVE	1
354 #define CP210X_SERIAL_DTR_FLOW_CTL	2
355 
356 /* cp210x_flow_ctl::ulFlowReplace */
357 #define CP210X_SERIAL_AUTO_TRANSMIT	BIT(0)
358 #define CP210X_SERIAL_AUTO_RECEIVE	BIT(1)
359 #define CP210X_SERIAL_ERROR_CHAR	BIT(2)
360 #define CP210X_SERIAL_NULL_STRIPPING	BIT(3)
361 #define CP210X_SERIAL_BREAK_CHAR	BIT(4)
362 #define CP210X_SERIAL_RTS_MASK		GENMASK(7, 6)
363 #define CP210X_SERIAL_RTS_SHIFT(_mode)	(_mode << 6)
364 #define CP210X_SERIAL_XOFF_CONTINUE	BIT(31)
365 
366 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
367 #define CP210X_SERIAL_RTS_INACTIVE	0
368 #define CP210X_SERIAL_RTS_ACTIVE	1
369 #define CP210X_SERIAL_RTS_FLOW_CTL	2
370 
371 /*
372  * Reads a variable-sized block of CP210X_ registers, identified by req.
373  * Returns data into buf in native USB byte order.
374  */
375 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
376 		void *buf, int bufsize)
377 {
378 	struct usb_serial *serial = port->serial;
379 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
380 	void *dmabuf;
381 	int result;
382 
383 	dmabuf = kmalloc(bufsize, GFP_KERNEL);
384 	if (!dmabuf) {
385 		/*
386 		 * FIXME Some callers don't bother to check for error,
387 		 * at least give them consistent junk until they are fixed
388 		 */
389 		memset(buf, 0, bufsize);
390 		return -ENOMEM;
391 	}
392 
393 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
394 			req, REQTYPE_INTERFACE_TO_HOST, 0,
395 			port_priv->bInterfaceNumber, dmabuf, bufsize,
396 			USB_CTRL_SET_TIMEOUT);
397 	if (result == bufsize) {
398 		memcpy(buf, dmabuf, bufsize);
399 		result = 0;
400 	} else {
401 		dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
402 				req, bufsize, result);
403 		if (result >= 0)
404 			result = -EPROTO;
405 
406 		/*
407 		 * FIXME Some callers don't bother to check for error,
408 		 * at least give them consistent junk until they are fixed
409 		 */
410 		memset(buf, 0, bufsize);
411 	}
412 
413 	kfree(dmabuf);
414 
415 	return result;
416 }
417 
418 /*
419  * Reads any 32-bit CP210X_ register identified by req.
420  */
421 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
422 {
423 	__le32 le32_val;
424 	int err;
425 
426 	err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
427 	if (err) {
428 		/*
429 		 * FIXME Some callers don't bother to check for error,
430 		 * at least give them consistent junk until they are fixed
431 		 */
432 		*val = 0;
433 		return err;
434 	}
435 
436 	*val = le32_to_cpu(le32_val);
437 
438 	return 0;
439 }
440 
441 /*
442  * Reads any 16-bit CP210X_ register identified by req.
443  */
444 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
445 {
446 	__le16 le16_val;
447 	int err;
448 
449 	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
450 	if (err)
451 		return err;
452 
453 	*val = le16_to_cpu(le16_val);
454 
455 	return 0;
456 }
457 
458 /*
459  * Reads any 8-bit CP210X_ register identified by req.
460  */
461 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
462 {
463 	return cp210x_read_reg_block(port, req, val, sizeof(*val));
464 }
465 
466 /*
467  * Writes any 16-bit CP210X_ register (req) whose value is passed
468  * entirely in the wValue field of the USB request.
469  */
470 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
471 {
472 	struct usb_serial *serial = port->serial;
473 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
474 	int result;
475 
476 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
477 			req, REQTYPE_HOST_TO_INTERFACE, val,
478 			port_priv->bInterfaceNumber, NULL, 0,
479 			USB_CTRL_SET_TIMEOUT);
480 	if (result < 0) {
481 		dev_err(&port->dev, "failed set request 0x%x status: %d\n",
482 				req, result);
483 	}
484 
485 	return result;
486 }
487 
488 /*
489  * Writes a variable-sized block of CP210X_ registers, identified by req.
490  * Data in buf must be in native USB byte order.
491  */
492 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
493 		void *buf, int bufsize)
494 {
495 	struct usb_serial *serial = port->serial;
496 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
497 	void *dmabuf;
498 	int result;
499 
500 	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
501 	if (!dmabuf)
502 		return -ENOMEM;
503 
504 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
505 			req, REQTYPE_HOST_TO_INTERFACE, 0,
506 			port_priv->bInterfaceNumber, dmabuf, bufsize,
507 			USB_CTRL_SET_TIMEOUT);
508 
509 	kfree(dmabuf);
510 
511 	if (result == bufsize) {
512 		result = 0;
513 	} else {
514 		dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
515 				req, bufsize, result);
516 		if (result >= 0)
517 			result = -EPROTO;
518 	}
519 
520 	return result;
521 }
522 
523 /*
524  * Writes any 32-bit CP210X_ register identified by req.
525  */
526 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
527 {
528 	__le32 le32_val;
529 
530 	le32_val = cpu_to_le32(val);
531 
532 	return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
533 }
534 
535 /*
536  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
537  * Write a known good value 0x800, read it back.
538  * If it comes back swapped the bug is detected.
539  * Preserve the original register value.
540  */
541 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
542 {
543 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
544 	u16 line_ctl_save;
545 	u16 line_ctl_test;
546 	int err;
547 
548 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
549 	if (err)
550 		return err;
551 
552 	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
553 	if (err)
554 		return err;
555 
556 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
557 	if (err)
558 		return err;
559 
560 	if (line_ctl_test == 8) {
561 		port_priv->has_swapped_line_ctl = true;
562 		line_ctl_save = swab16(line_ctl_save);
563 	}
564 
565 	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
566 }
567 
568 /*
569  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
570  * to workaround cp2108 bug and get correct value.
571  */
572 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
573 {
574 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
575 	int err;
576 
577 	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
578 	if (err)
579 		return err;
580 
581 	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
582 	if (port_priv->has_swapped_line_ctl)
583 		*ctl = swab16(*ctl);
584 
585 	return 0;
586 }
587 
588 /*
589  * cp210x_quantise_baudrate
590  * Quantises the baud rate as per AN205 Table 1
591  */
592 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
593 {
594 	if (baud <= 300)
595 		baud = 300;
596 	else if (baud <= 600)      baud = 600;
597 	else if (baud <= 1200)     baud = 1200;
598 	else if (baud <= 1800)     baud = 1800;
599 	else if (baud <= 2400)     baud = 2400;
600 	else if (baud <= 4000)     baud = 4000;
601 	else if (baud <= 4803)     baud = 4800;
602 	else if (baud <= 7207)     baud = 7200;
603 	else if (baud <= 9612)     baud = 9600;
604 	else if (baud <= 14428)    baud = 14400;
605 	else if (baud <= 16062)    baud = 16000;
606 	else if (baud <= 19250)    baud = 19200;
607 	else if (baud <= 28912)    baud = 28800;
608 	else if (baud <= 38601)    baud = 38400;
609 	else if (baud <= 51558)    baud = 51200;
610 	else if (baud <= 56280)    baud = 56000;
611 	else if (baud <= 58053)    baud = 57600;
612 	else if (baud <= 64111)    baud = 64000;
613 	else if (baud <= 77608)    baud = 76800;
614 	else if (baud <= 117028)   baud = 115200;
615 	else if (baud <= 129347)   baud = 128000;
616 	else if (baud <= 156868)   baud = 153600;
617 	else if (baud <= 237832)   baud = 230400;
618 	else if (baud <= 254234)   baud = 250000;
619 	else if (baud <= 273066)   baud = 256000;
620 	else if (baud <= 491520)   baud = 460800;
621 	else if (baud <= 567138)   baud = 500000;
622 	else if (baud <= 670254)   baud = 576000;
623 	else if (baud < 1000000)
624 		baud = 921600;
625 	else if (baud > 2000000)
626 		baud = 2000000;
627 	return baud;
628 }
629 
630 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
631 {
632 	int result;
633 
634 	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
635 	if (result) {
636 		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
637 		return result;
638 	}
639 
640 	/* Configure the termios structure */
641 	cp210x_get_termios(tty, port);
642 
643 	/* The baud rate must be initialised on cp2104 */
644 	if (tty)
645 		cp210x_change_speed(tty, port, NULL);
646 
647 	return usb_serial_generic_open(tty, port);
648 }
649 
650 static void cp210x_close(struct usb_serial_port *port)
651 {
652 	usb_serial_generic_close(port);
653 
654 	/* Clear both queues; cp2108 needs this to avoid an occasional hang */
655 	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
656 
657 	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
658 }
659 
660 /*
661  * Read how many bytes are waiting in the TX queue.
662  */
663 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
664 		u32 *count)
665 {
666 	struct usb_serial *serial = port->serial;
667 	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
668 	struct cp210x_comm_status *sts;
669 	int result;
670 
671 	sts = kmalloc(sizeof(*sts), GFP_KERNEL);
672 	if (!sts)
673 		return -ENOMEM;
674 
675 	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
676 			CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
677 			0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
678 			USB_CTRL_GET_TIMEOUT);
679 	if (result == sizeof(*sts)) {
680 		*count = le32_to_cpu(sts->ulAmountInOutQueue);
681 		result = 0;
682 	} else {
683 		dev_err(&port->dev, "failed to get comm status: %d\n", result);
684 		if (result >= 0)
685 			result = -EPROTO;
686 	}
687 
688 	kfree(sts);
689 
690 	return result;
691 }
692 
693 static bool cp210x_tx_empty(struct usb_serial_port *port)
694 {
695 	int err;
696 	u32 count;
697 
698 	err = cp210x_get_tx_queue_byte_count(port, &count);
699 	if (err)
700 		return true;
701 
702 	return !count;
703 }
704 
705 /*
706  * cp210x_get_termios
707  * Reads the baud rate, data bits, parity, stop bits and flow control mode
708  * from the device, corrects any unsupported values, and configures the
709  * termios structure to reflect the state of the device
710  */
711 static void cp210x_get_termios(struct tty_struct *tty,
712 	struct usb_serial_port *port)
713 {
714 	unsigned int baud;
715 
716 	if (tty) {
717 		cp210x_get_termios_port(tty->driver_data,
718 			&tty->termios.c_cflag, &baud);
719 		tty_encode_baud_rate(tty, baud, baud);
720 	} else {
721 		unsigned int cflag;
722 		cflag = 0;
723 		cp210x_get_termios_port(port, &cflag, &baud);
724 	}
725 }
726 
727 /*
728  * cp210x_get_termios_port
729  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
730  */
731 static void cp210x_get_termios_port(struct usb_serial_port *port,
732 	unsigned int *cflagp, unsigned int *baudp)
733 {
734 	struct device *dev = &port->dev;
735 	unsigned int cflag;
736 	struct cp210x_flow_ctl flow_ctl;
737 	u32 baud;
738 	u16 bits;
739 	u32 ctl_hs;
740 
741 	cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
742 
743 	dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
744 	*baudp = baud;
745 
746 	cflag = *cflagp;
747 
748 	cp210x_get_line_ctl(port, &bits);
749 	cflag &= ~CSIZE;
750 	switch (bits & BITS_DATA_MASK) {
751 	case BITS_DATA_5:
752 		dev_dbg(dev, "%s - data bits = 5\n", __func__);
753 		cflag |= CS5;
754 		break;
755 	case BITS_DATA_6:
756 		dev_dbg(dev, "%s - data bits = 6\n", __func__);
757 		cflag |= CS6;
758 		break;
759 	case BITS_DATA_7:
760 		dev_dbg(dev, "%s - data bits = 7\n", __func__);
761 		cflag |= CS7;
762 		break;
763 	case BITS_DATA_8:
764 		dev_dbg(dev, "%s - data bits = 8\n", __func__);
765 		cflag |= CS8;
766 		break;
767 	case BITS_DATA_9:
768 		dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
769 		cflag |= CS8;
770 		bits &= ~BITS_DATA_MASK;
771 		bits |= BITS_DATA_8;
772 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
773 		break;
774 	default:
775 		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
776 		cflag |= CS8;
777 		bits &= ~BITS_DATA_MASK;
778 		bits |= BITS_DATA_8;
779 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
780 		break;
781 	}
782 
783 	switch (bits & BITS_PARITY_MASK) {
784 	case BITS_PARITY_NONE:
785 		dev_dbg(dev, "%s - parity = NONE\n", __func__);
786 		cflag &= ~PARENB;
787 		break;
788 	case BITS_PARITY_ODD:
789 		dev_dbg(dev, "%s - parity = ODD\n", __func__);
790 		cflag |= (PARENB|PARODD);
791 		break;
792 	case BITS_PARITY_EVEN:
793 		dev_dbg(dev, "%s - parity = EVEN\n", __func__);
794 		cflag &= ~PARODD;
795 		cflag |= PARENB;
796 		break;
797 	case BITS_PARITY_MARK:
798 		dev_dbg(dev, "%s - parity = MARK\n", __func__);
799 		cflag |= (PARENB|PARODD|CMSPAR);
800 		break;
801 	case BITS_PARITY_SPACE:
802 		dev_dbg(dev, "%s - parity = SPACE\n", __func__);
803 		cflag &= ~PARODD;
804 		cflag |= (PARENB|CMSPAR);
805 		break;
806 	default:
807 		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
808 		cflag &= ~PARENB;
809 		bits &= ~BITS_PARITY_MASK;
810 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
811 		break;
812 	}
813 
814 	cflag &= ~CSTOPB;
815 	switch (bits & BITS_STOP_MASK) {
816 	case BITS_STOP_1:
817 		dev_dbg(dev, "%s - stop bits = 1\n", __func__);
818 		break;
819 	case BITS_STOP_1_5:
820 		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
821 		bits &= ~BITS_STOP_MASK;
822 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
823 		break;
824 	case BITS_STOP_2:
825 		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
826 		cflag |= CSTOPB;
827 		break;
828 	default:
829 		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
830 		bits &= ~BITS_STOP_MASK;
831 		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
832 		break;
833 	}
834 
835 	cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
836 			sizeof(flow_ctl));
837 	ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
838 	if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
839 		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
840 		cflag |= CRTSCTS;
841 	} else {
842 		dev_dbg(dev, "%s - flow control = NONE\n", __func__);
843 		cflag &= ~CRTSCTS;
844 	}
845 
846 	*cflagp = cflag;
847 }
848 
849 /*
850  * CP2101 supports the following baud rates:
851  *
852  *	300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
853  *	38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
854  *
855  * CP2102 and CP2103 support the following additional rates:
856  *
857  *	4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
858  *	576000
859  *
860  * The device will map a requested rate to a supported one, but the result
861  * of requests for rates greater than 1053257 is undefined (see AN205).
862  *
863  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
864  * respectively, with an error less than 1%. The actual rates are determined
865  * by
866  *
867  *	div = round(freq / (2 x prescale x request))
868  *	actual = freq / (2 x prescale x div)
869  *
870  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
871  * or 1 otherwise.
872  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
873  * otherwise.
874  */
875 static void cp210x_change_speed(struct tty_struct *tty,
876 		struct usb_serial_port *port, struct ktermios *old_termios)
877 {
878 	u32 baud;
879 
880 	baud = tty->termios.c_ospeed;
881 
882 	/* This maps the requested rate to a rate valid on cp2102 or cp2103,
883 	 * or to an arbitrary rate in [1M,2M].
884 	 *
885 	 * NOTE: B0 is not implemented.
886 	 */
887 	baud = cp210x_quantise_baudrate(baud);
888 
889 	dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
890 	if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
891 		dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
892 		if (old_termios)
893 			baud = old_termios->c_ospeed;
894 		else
895 			baud = 9600;
896 	}
897 
898 	tty_encode_baud_rate(tty, baud, baud);
899 }
900 
901 static void cp210x_set_termios(struct tty_struct *tty,
902 		struct usb_serial_port *port, struct ktermios *old_termios)
903 {
904 	struct device *dev = &port->dev;
905 	unsigned int cflag, old_cflag;
906 	u16 bits;
907 
908 	cflag = tty->termios.c_cflag;
909 	old_cflag = old_termios->c_cflag;
910 
911 	if (tty->termios.c_ospeed != old_termios->c_ospeed)
912 		cp210x_change_speed(tty, port, old_termios);
913 
914 	/* If the number of data bits is to be updated */
915 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
916 		cp210x_get_line_ctl(port, &bits);
917 		bits &= ~BITS_DATA_MASK;
918 		switch (cflag & CSIZE) {
919 		case CS5:
920 			bits |= BITS_DATA_5;
921 			dev_dbg(dev, "%s - data bits = 5\n", __func__);
922 			break;
923 		case CS6:
924 			bits |= BITS_DATA_6;
925 			dev_dbg(dev, "%s - data bits = 6\n", __func__);
926 			break;
927 		case CS7:
928 			bits |= BITS_DATA_7;
929 			dev_dbg(dev, "%s - data bits = 7\n", __func__);
930 			break;
931 		case CS8:
932 			bits |= BITS_DATA_8;
933 			dev_dbg(dev, "%s - data bits = 8\n", __func__);
934 			break;
935 		/*case CS9:
936 			bits |= BITS_DATA_9;
937 			dev_dbg(dev, "%s - data bits = 9\n", __func__);
938 			break;*/
939 		default:
940 			dev_dbg(dev, "cp210x driver does not support the number of bits requested, using 8 bit mode\n");
941 			bits |= BITS_DATA_8;
942 			break;
943 		}
944 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
945 			dev_dbg(dev, "Number of data bits requested not supported by device\n");
946 	}
947 
948 	if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
949 	    (old_cflag & (PARENB|PARODD|CMSPAR))) {
950 		cp210x_get_line_ctl(port, &bits);
951 		bits &= ~BITS_PARITY_MASK;
952 		if (cflag & PARENB) {
953 			if (cflag & CMSPAR) {
954 				if (cflag & PARODD) {
955 					bits |= BITS_PARITY_MARK;
956 					dev_dbg(dev, "%s - parity = MARK\n", __func__);
957 				} else {
958 					bits |= BITS_PARITY_SPACE;
959 					dev_dbg(dev, "%s - parity = SPACE\n", __func__);
960 				}
961 			} else {
962 				if (cflag & PARODD) {
963 					bits |= BITS_PARITY_ODD;
964 					dev_dbg(dev, "%s - parity = ODD\n", __func__);
965 				} else {
966 					bits |= BITS_PARITY_EVEN;
967 					dev_dbg(dev, "%s - parity = EVEN\n", __func__);
968 				}
969 			}
970 		}
971 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
972 			dev_dbg(dev, "Parity mode not supported by device\n");
973 	}
974 
975 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
976 		cp210x_get_line_ctl(port, &bits);
977 		bits &= ~BITS_STOP_MASK;
978 		if (cflag & CSTOPB) {
979 			bits |= BITS_STOP_2;
980 			dev_dbg(dev, "%s - stop bits = 2\n", __func__);
981 		} else {
982 			bits |= BITS_STOP_1;
983 			dev_dbg(dev, "%s - stop bits = 1\n", __func__);
984 		}
985 		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
986 			dev_dbg(dev, "Number of stop bits requested not supported by device\n");
987 	}
988 
989 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
990 		struct cp210x_flow_ctl flow_ctl;
991 		u32 ctl_hs;
992 		u32 flow_repl;
993 
994 		cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
995 				sizeof(flow_ctl));
996 		ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
997 		flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
998 		dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
999 				__func__, ctl_hs, flow_repl);
1000 
1001 		ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1002 		ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1003 		ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1004 		ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1005 		ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1006 		if (cflag & CRTSCTS) {
1007 			ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1008 
1009 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1010 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1011 					CP210X_SERIAL_RTS_FLOW_CTL);
1012 			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1013 		} else {
1014 			ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1015 
1016 			flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1017 			flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1018 					CP210X_SERIAL_RTS_ACTIVE);
1019 			dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1020 		}
1021 
1022 		dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1023 				__func__, ctl_hs, flow_repl);
1024 		flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1025 		flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1026 		cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1027 				sizeof(flow_ctl));
1028 	}
1029 
1030 }
1031 
1032 static int cp210x_tiocmset(struct tty_struct *tty,
1033 		unsigned int set, unsigned int clear)
1034 {
1035 	struct usb_serial_port *port = tty->driver_data;
1036 	return cp210x_tiocmset_port(port, set, clear);
1037 }
1038 
1039 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1040 		unsigned int set, unsigned int clear)
1041 {
1042 	u16 control = 0;
1043 
1044 	if (set & TIOCM_RTS) {
1045 		control |= CONTROL_RTS;
1046 		control |= CONTROL_WRITE_RTS;
1047 	}
1048 	if (set & TIOCM_DTR) {
1049 		control |= CONTROL_DTR;
1050 		control |= CONTROL_WRITE_DTR;
1051 	}
1052 	if (clear & TIOCM_RTS) {
1053 		control &= ~CONTROL_RTS;
1054 		control |= CONTROL_WRITE_RTS;
1055 	}
1056 	if (clear & TIOCM_DTR) {
1057 		control &= ~CONTROL_DTR;
1058 		control |= CONTROL_WRITE_DTR;
1059 	}
1060 
1061 	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1062 
1063 	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1064 }
1065 
1066 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1067 {
1068 	if (on)
1069 		cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1070 	else
1071 		cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1072 }
1073 
1074 static int cp210x_tiocmget(struct tty_struct *tty)
1075 {
1076 	struct usb_serial_port *port = tty->driver_data;
1077 	u8 control;
1078 	int result;
1079 
1080 	cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1081 
1082 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1083 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1084 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1085 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1086 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
1087 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1088 
1089 	dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1090 
1091 	return result;
1092 }
1093 
1094 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1095 {
1096 	struct usb_serial_port *port = tty->driver_data;
1097 	u16 state;
1098 
1099 	if (break_state == 0)
1100 		state = BREAK_OFF;
1101 	else
1102 		state = BREAK_ON;
1103 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1104 		state == BREAK_OFF ? "off" : "on");
1105 	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1106 }
1107 
1108 static int cp210x_port_probe(struct usb_serial_port *port)
1109 {
1110 	struct usb_serial *serial = port->serial;
1111 	struct usb_host_interface *cur_altsetting;
1112 	struct cp210x_port_private *port_priv;
1113 	int ret;
1114 
1115 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1116 	if (!port_priv)
1117 		return -ENOMEM;
1118 
1119 	cur_altsetting = serial->interface->cur_altsetting;
1120 	port_priv->bInterfaceNumber = cur_altsetting->desc.bInterfaceNumber;
1121 
1122 	usb_set_serial_port_data(port, port_priv);
1123 
1124 	ret = cp210x_detect_swapped_line_ctl(port);
1125 	if (ret) {
1126 		kfree(port_priv);
1127 		return ret;
1128 	}
1129 
1130 	return 0;
1131 }
1132 
1133 static int cp210x_port_remove(struct usb_serial_port *port)
1134 {
1135 	struct cp210x_port_private *port_priv;
1136 
1137 	port_priv = usb_get_serial_port_data(port);
1138 	kfree(port_priv);
1139 
1140 	return 0;
1141 }
1142 
1143 module_usb_serial_driver(serial_drivers, id_table);
1144 
1145 MODULE_DESCRIPTION(DRIVER_DESC);
1146 MODULE_LICENSE("GPL");
1147