1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Renesas Electronics uPD78F0730 USB to serial converter driver
4 *
5 * Copyright (C) 2014,2016 Maksim Salau <maksim.salau@gmail.com>
6 *
7 * Protocol of the adaptor is described in the application note U19660EJ1V0AN00
8 * μPD78F0730 8-bit Single-Chip Microcontroller
9 * USB-to-Serial Conversion Software
10 * <https://www.renesas.com/en-eu/doc/DocumentServer/026/U19660EJ1V0AN00.pdf>
11 *
12 * The adaptor functionality is limited to the following:
13 * - data bits: 7 or 8
14 * - stop bits: 1 or 2
15 * - parity: even, odd or none
16 * - flow control: none
17 * - baud rates: 0, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 153600
18 * - signals: DTR, RTS and BREAK
19 */
20
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/tty.h>
24 #include <linux/usb.h>
25 #include <linux/usb/serial.h>
26
27 #define DRIVER_DESC "Renesas uPD78F0730 USB to serial converter driver"
28
29 #define DRIVER_AUTHOR "Maksim Salau <maksim.salau@gmail.com>"
30
31 static const struct usb_device_id id_table[] = {
32 { USB_DEVICE(0x0409, 0x0063) }, /* V850ESJX3-STICK */
33 { USB_DEVICE(0x045B, 0x0212) }, /* YRPBRL78G13, YRPBRL78G14 */
34 { USB_DEVICE(0x064B, 0x7825) }, /* Analog Devices EVAL-ADXL362Z-DB */
35 {}
36 };
37
38 MODULE_DEVICE_TABLE(usb, id_table);
39
40 /*
41 * Each adaptor is associated with a private structure, that holds the current
42 * state of control signals (DTR, RTS and BREAK).
43 */
44 struct upd78f0730_port_private {
45 struct mutex lock; /* mutex to protect line_signals */
46 u8 line_signals;
47 };
48
49 /* Op-codes of control commands */
50 #define UPD78F0730_CMD_LINE_CONTROL 0x00
51 #define UPD78F0730_CMD_SET_DTR_RTS 0x01
52 #define UPD78F0730_CMD_SET_XON_XOFF_CHR 0x02
53 #define UPD78F0730_CMD_OPEN_CLOSE 0x03
54 #define UPD78F0730_CMD_SET_ERR_CHR 0x04
55
56 /* Data sizes in UPD78F0730_CMD_LINE_CONTROL command */
57 #define UPD78F0730_DATA_SIZE_7_BITS 0x00
58 #define UPD78F0730_DATA_SIZE_8_BITS 0x01
59 #define UPD78F0730_DATA_SIZE_MASK 0x01
60
61 /* Stop-bit modes in UPD78F0730_CMD_LINE_CONTROL command */
62 #define UPD78F0730_STOP_BIT_1_BIT 0x00
63 #define UPD78F0730_STOP_BIT_2_BIT 0x02
64 #define UPD78F0730_STOP_BIT_MASK 0x02
65
66 /* Parity modes in UPD78F0730_CMD_LINE_CONTROL command */
67 #define UPD78F0730_PARITY_NONE 0x00
68 #define UPD78F0730_PARITY_EVEN 0x04
69 #define UPD78F0730_PARITY_ODD 0x08
70 #define UPD78F0730_PARITY_MASK 0x0C
71
72 /* Flow control modes in UPD78F0730_CMD_LINE_CONTROL command */
73 #define UPD78F0730_FLOW_CONTROL_NONE 0x00
74 #define UPD78F0730_FLOW_CONTROL_HW 0x10
75 #define UPD78F0730_FLOW_CONTROL_SW 0x20
76 #define UPD78F0730_FLOW_CONTROL_MASK 0x30
77
78 /* Control signal bits in UPD78F0730_CMD_SET_DTR_RTS command */
79 #define UPD78F0730_RTS 0x01
80 #define UPD78F0730_DTR 0x02
81 #define UPD78F0730_BREAK 0x04
82
83 /* Port modes in UPD78F0730_CMD_OPEN_CLOSE command */
84 #define UPD78F0730_PORT_CLOSE 0x00
85 #define UPD78F0730_PORT_OPEN 0x01
86
87 /* Error character substitution modes in UPD78F0730_CMD_SET_ERR_CHR command */
88 #define UPD78F0730_ERR_CHR_DISABLED 0x00
89 #define UPD78F0730_ERR_CHR_ENABLED 0x01
90
91 /*
92 * Declaration of command structures
93 */
94
95 /* UPD78F0730_CMD_LINE_CONTROL command */
96 struct upd78f0730_line_control {
97 u8 opcode;
98 __le32 baud_rate;
99 u8 params;
100 } __packed;
101
102 /* UPD78F0730_CMD_SET_DTR_RTS command */
103 struct upd78f0730_set_dtr_rts {
104 u8 opcode;
105 u8 params;
106 };
107
108 /* UPD78F0730_CMD_SET_XON_OFF_CHR command */
109 struct upd78f0730_set_xon_xoff_chr {
110 u8 opcode;
111 u8 xon;
112 u8 xoff;
113 };
114
115 /* UPD78F0730_CMD_OPEN_CLOSE command */
116 struct upd78f0730_open_close {
117 u8 opcode;
118 u8 state;
119 };
120
121 /* UPD78F0730_CMD_SET_ERR_CHR command */
122 struct upd78f0730_set_err_chr {
123 u8 opcode;
124 u8 state;
125 u8 err_char;
126 };
127
upd78f0730_send_ctl(struct usb_serial_port * port,const void * data,int size)128 static int upd78f0730_send_ctl(struct usb_serial_port *port,
129 const void *data, int size)
130 {
131 struct usb_device *usbdev = port->serial->dev;
132 void *buf;
133 int res;
134
135 if (size <= 0 || !data)
136 return -EINVAL;
137
138 buf = kmemdup(data, size, GFP_KERNEL);
139 if (!buf)
140 return -ENOMEM;
141
142 res = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x00,
143 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
144 0x0000, 0x0000, buf, size, USB_CTRL_SET_TIMEOUT);
145
146 kfree(buf);
147
148 if (res < 0) {
149 struct device *dev = &port->dev;
150
151 dev_err(dev, "failed to send control request %02x: %d\n",
152 *(u8 *)data, res);
153
154 return res;
155 }
156
157 return 0;
158 }
159
upd78f0730_port_probe(struct usb_serial_port * port)160 static int upd78f0730_port_probe(struct usb_serial_port *port)
161 {
162 struct upd78f0730_port_private *private;
163
164 private = kzalloc(sizeof(*private), GFP_KERNEL);
165 if (!private)
166 return -ENOMEM;
167
168 mutex_init(&private->lock);
169 usb_set_serial_port_data(port, private);
170
171 return 0;
172 }
173
upd78f0730_port_remove(struct usb_serial_port * port)174 static void upd78f0730_port_remove(struct usb_serial_port *port)
175 {
176 struct upd78f0730_port_private *private;
177
178 private = usb_get_serial_port_data(port);
179 mutex_destroy(&private->lock);
180 kfree(private);
181 }
182
upd78f0730_tiocmget(struct tty_struct * tty)183 static int upd78f0730_tiocmget(struct tty_struct *tty)
184 {
185 struct upd78f0730_port_private *private;
186 struct usb_serial_port *port = tty->driver_data;
187 int signals;
188 int res;
189
190 private = usb_get_serial_port_data(port);
191
192 mutex_lock(&private->lock);
193 signals = private->line_signals;
194 mutex_unlock(&private->lock);
195
196 res = ((signals & UPD78F0730_DTR) ? TIOCM_DTR : 0) |
197 ((signals & UPD78F0730_RTS) ? TIOCM_RTS : 0);
198
199 dev_dbg(&port->dev, "%s - res = %x\n", __func__, res);
200
201 return res;
202 }
203
upd78f0730_tiocmset(struct tty_struct * tty,unsigned int set,unsigned int clear)204 static int upd78f0730_tiocmset(struct tty_struct *tty,
205 unsigned int set, unsigned int clear)
206 {
207 struct usb_serial_port *port = tty->driver_data;
208 struct upd78f0730_port_private *private;
209 struct upd78f0730_set_dtr_rts request;
210 struct device *dev = &port->dev;
211 int res;
212
213 private = usb_get_serial_port_data(port);
214
215 mutex_lock(&private->lock);
216 if (set & TIOCM_DTR) {
217 private->line_signals |= UPD78F0730_DTR;
218 dev_dbg(dev, "%s - set DTR\n", __func__);
219 }
220 if (set & TIOCM_RTS) {
221 private->line_signals |= UPD78F0730_RTS;
222 dev_dbg(dev, "%s - set RTS\n", __func__);
223 }
224 if (clear & TIOCM_DTR) {
225 private->line_signals &= ~UPD78F0730_DTR;
226 dev_dbg(dev, "%s - clear DTR\n", __func__);
227 }
228 if (clear & TIOCM_RTS) {
229 private->line_signals &= ~UPD78F0730_RTS;
230 dev_dbg(dev, "%s - clear RTS\n", __func__);
231 }
232 request.opcode = UPD78F0730_CMD_SET_DTR_RTS;
233 request.params = private->line_signals;
234
235 res = upd78f0730_send_ctl(port, &request, sizeof(request));
236 mutex_unlock(&private->lock);
237
238 return res;
239 }
240
upd78f0730_break_ctl(struct tty_struct * tty,int break_state)241 static void upd78f0730_break_ctl(struct tty_struct *tty, int break_state)
242 {
243 struct upd78f0730_port_private *private;
244 struct usb_serial_port *port = tty->driver_data;
245 struct upd78f0730_set_dtr_rts request;
246 struct device *dev = &port->dev;
247
248 private = usb_get_serial_port_data(port);
249
250 mutex_lock(&private->lock);
251 if (break_state) {
252 private->line_signals |= UPD78F0730_BREAK;
253 dev_dbg(dev, "%s - set BREAK\n", __func__);
254 } else {
255 private->line_signals &= ~UPD78F0730_BREAK;
256 dev_dbg(dev, "%s - clear BREAK\n", __func__);
257 }
258 request.opcode = UPD78F0730_CMD_SET_DTR_RTS;
259 request.params = private->line_signals;
260
261 upd78f0730_send_ctl(port, &request, sizeof(request));
262 mutex_unlock(&private->lock);
263 }
264
upd78f0730_dtr_rts(struct usb_serial_port * port,int on)265 static void upd78f0730_dtr_rts(struct usb_serial_port *port, int on)
266 {
267 struct tty_struct *tty = port->port.tty;
268 unsigned int set = 0;
269 unsigned int clear = 0;
270
271 if (on)
272 set = TIOCM_DTR | TIOCM_RTS;
273 else
274 clear = TIOCM_DTR | TIOCM_RTS;
275
276 upd78f0730_tiocmset(tty, set, clear);
277 }
278
upd78f0730_get_baud_rate(struct tty_struct * tty)279 static speed_t upd78f0730_get_baud_rate(struct tty_struct *tty)
280 {
281 const speed_t baud_rate = tty_get_baud_rate(tty);
282 static const speed_t supported[] = {
283 0, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 153600
284 };
285 int i;
286
287 for (i = ARRAY_SIZE(supported) - 1; i >= 0; i--) {
288 if (baud_rate == supported[i])
289 return baud_rate;
290 }
291
292 /* If the baud rate is not supported, switch to the default one */
293 tty_encode_baud_rate(tty, 9600, 9600);
294
295 return tty_get_baud_rate(tty);
296 }
297
upd78f0730_set_termios(struct tty_struct * tty,struct usb_serial_port * port,struct ktermios * old_termios)298 static void upd78f0730_set_termios(struct tty_struct *tty,
299 struct usb_serial_port *port,
300 struct ktermios *old_termios)
301 {
302 struct device *dev = &port->dev;
303 struct upd78f0730_line_control request;
304 speed_t baud_rate;
305
306 if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
307 return;
308
309 if (C_BAUD(tty) == B0)
310 upd78f0730_dtr_rts(port, 0);
311 else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
312 upd78f0730_dtr_rts(port, 1);
313
314 baud_rate = upd78f0730_get_baud_rate(tty);
315 request.opcode = UPD78F0730_CMD_LINE_CONTROL;
316 request.baud_rate = cpu_to_le32(baud_rate);
317 request.params = 0;
318 dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud_rate);
319
320 switch (C_CSIZE(tty)) {
321 case CS7:
322 request.params |= UPD78F0730_DATA_SIZE_7_BITS;
323 dev_dbg(dev, "%s - 7 data bits\n", __func__);
324 break;
325 default:
326 tty->termios.c_cflag &= ~CSIZE;
327 tty->termios.c_cflag |= CS8;
328 dev_warn(dev, "data size is not supported, using 8 bits\n");
329 fallthrough;
330 case CS8:
331 request.params |= UPD78F0730_DATA_SIZE_8_BITS;
332 dev_dbg(dev, "%s - 8 data bits\n", __func__);
333 break;
334 }
335
336 if (C_PARENB(tty)) {
337 if (C_PARODD(tty)) {
338 request.params |= UPD78F0730_PARITY_ODD;
339 dev_dbg(dev, "%s - odd parity\n", __func__);
340 } else {
341 request.params |= UPD78F0730_PARITY_EVEN;
342 dev_dbg(dev, "%s - even parity\n", __func__);
343 }
344
345 if (C_CMSPAR(tty)) {
346 tty->termios.c_cflag &= ~CMSPAR;
347 dev_warn(dev, "MARK/SPACE parity is not supported\n");
348 }
349 } else {
350 request.params |= UPD78F0730_PARITY_NONE;
351 dev_dbg(dev, "%s - no parity\n", __func__);
352 }
353
354 if (C_CSTOPB(tty)) {
355 request.params |= UPD78F0730_STOP_BIT_2_BIT;
356 dev_dbg(dev, "%s - 2 stop bits\n", __func__);
357 } else {
358 request.params |= UPD78F0730_STOP_BIT_1_BIT;
359 dev_dbg(dev, "%s - 1 stop bit\n", __func__);
360 }
361
362 if (C_CRTSCTS(tty)) {
363 tty->termios.c_cflag &= ~CRTSCTS;
364 dev_warn(dev, "RTSCTS flow control is not supported\n");
365 }
366 if (I_IXOFF(tty) || I_IXON(tty)) {
367 tty->termios.c_iflag &= ~(IXOFF | IXON);
368 dev_warn(dev, "XON/XOFF flow control is not supported\n");
369 }
370 request.params |= UPD78F0730_FLOW_CONTROL_NONE;
371 dev_dbg(dev, "%s - no flow control\n", __func__);
372
373 upd78f0730_send_ctl(port, &request, sizeof(request));
374 }
375
upd78f0730_open(struct tty_struct * tty,struct usb_serial_port * port)376 static int upd78f0730_open(struct tty_struct *tty, struct usb_serial_port *port)
377 {
378 static const struct upd78f0730_open_close request = {
379 .opcode = UPD78F0730_CMD_OPEN_CLOSE,
380 .state = UPD78F0730_PORT_OPEN
381 };
382 int res;
383
384 res = upd78f0730_send_ctl(port, &request, sizeof(request));
385 if (res)
386 return res;
387
388 if (tty)
389 upd78f0730_set_termios(tty, port, NULL);
390
391 return usb_serial_generic_open(tty, port);
392 }
393
upd78f0730_close(struct usb_serial_port * port)394 static void upd78f0730_close(struct usb_serial_port *port)
395 {
396 static const struct upd78f0730_open_close request = {
397 .opcode = UPD78F0730_CMD_OPEN_CLOSE,
398 .state = UPD78F0730_PORT_CLOSE
399 };
400
401 usb_serial_generic_close(port);
402 upd78f0730_send_ctl(port, &request, sizeof(request));
403 }
404
405 static struct usb_serial_driver upd78f0730_device = {
406 .driver = {
407 .owner = THIS_MODULE,
408 .name = "upd78f0730",
409 },
410 .id_table = id_table,
411 .num_ports = 1,
412 .port_probe = upd78f0730_port_probe,
413 .port_remove = upd78f0730_port_remove,
414 .open = upd78f0730_open,
415 .close = upd78f0730_close,
416 .set_termios = upd78f0730_set_termios,
417 .tiocmget = upd78f0730_tiocmget,
418 .tiocmset = upd78f0730_tiocmset,
419 .dtr_rts = upd78f0730_dtr_rts,
420 .break_ctl = upd78f0730_break_ctl,
421 };
422
423 static struct usb_serial_driver * const serial_drivers[] = {
424 &upd78f0730_device,
425 NULL
426 };
427
428 module_usb_serial_driver(serial_drivers, id_table);
429
430 MODULE_DESCRIPTION(DRIVER_DESC);
431 MODULE_AUTHOR(DRIVER_AUTHOR);
432 MODULE_LICENSE("GPL v2");
433