1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Wacom protocol 4 serial tablet driver
4 *
5 * Copyright 2014 Hans de Goede <hdegoede@redhat.com>
6 * Copyright 2011-2012 Julian Squires <julian@cipht.net>
7 *
8 * Many thanks to Bill Seremetis, without whom PenPartner support
9 * would not have been possible. Thanks to Patrick Mahoney.
10 *
11 * This driver was developed with reference to much code written by others,
12 * particularly:
13 * - elo, gunze drivers by Vojtech Pavlik <vojtech@ucw.cz>;
14 * - wacom_w8001 driver by Jaya Kumar <jayakumar.lkml@gmail.com>;
15 * - the USB wacom input driver, credited to many people
16 * (see drivers/input/tablet/wacom.h);
17 * - new and old versions of linuxwacom / xf86-input-wacom credited to
18 * Frederic Lepied, France. <Lepied@XFree86.org> and
19 * Ping Cheng, Wacom. <pingc@wacom.com>;
20 * - and xf86wacom.c (a presumably ancient version of the linuxwacom code),
21 * by Frederic Lepied and Raph Levien <raph@gtk.org>.
22 *
23 * To do:
24 * - support pad buttons; (requires access to a model with pad buttons)
25 * - support (protocol 4-style) tilt (requires access to a > 1.4 rom model)
26 */
27
28 /*
29 * Wacom serial protocol 4 documentation taken from linuxwacom-0.9.9 code,
30 * protocol 4 uses 7 or 9 byte of data in the following format:
31 *
32 * Byte 1
33 * bit 7 Sync bit always 1
34 * bit 6 Pointing device detected
35 * bit 5 Cursor = 0 / Stylus = 1
36 * bit 4 Reserved
37 * bit 3 1 if a button on the pointing device has been pressed
38 * bit 2 P0 (optional)
39 * bit 1 X15
40 * bit 0 X14
41 *
42 * Byte 2
43 * bit 7 Always 0
44 * bits 6-0 = X13 - X7
45 *
46 * Byte 3
47 * bit 7 Always 0
48 * bits 6-0 = X6 - X0
49 *
50 * Byte 4
51 * bit 7 Always 0
52 * bit 6 B3
53 * bit 5 B2
54 * bit 4 B1
55 * bit 3 B0
56 * bit 2 P1 (optional)
57 * bit 1 Y15
58 * bit 0 Y14
59 *
60 * Byte 5
61 * bit 7 Always 0
62 * bits 6-0 = Y13 - Y7
63 *
64 * Byte 6
65 * bit 7 Always 0
66 * bits 6-0 = Y6 - Y0
67 *
68 * Byte 7
69 * bit 7 Always 0
70 * bit 6 Sign of pressure data; or wheel-rel for cursor tool
71 * bit 5 P7; or REL1 for cursor tool
72 * bit 4 P6; or REL0 for cursor tool
73 * bit 3 P5
74 * bit 2 P4
75 * bit 1 P3
76 * bit 0 P2
77 *
78 * byte 8 and 9 are optional and present only
79 * in tilt mode.
80 *
81 * Byte 8
82 * bit 7 Always 0
83 * bit 6 Sign of tilt X
84 * bit 5 Xt6
85 * bit 4 Xt5
86 * bit 3 Xt4
87 * bit 2 Xt3
88 * bit 1 Xt2
89 * bit 0 Xt1
90 *
91 * Byte 9
92 * bit 7 Always 0
93 * bit 6 Sign of tilt Y
94 * bit 5 Yt6
95 * bit 4 Yt5
96 * bit 3 Yt4
97 * bit 2 Yt3
98 * bit 1 Yt2
99 * bit 0 Yt1
100 */
101
102 #include <linux/completion.h>
103 #include <linux/init.h>
104 #include <linux/input.h>
105 #include <linux/interrupt.h>
106 #include <linux/kernel.h>
107 #include <linux/module.h>
108 #include <linux/serio.h>
109 #include <linux/slab.h>
110 #include <linux/string.h>
111
112 MODULE_AUTHOR("Julian Squires <julian@cipht.net>, Hans de Goede <hdegoede@redhat.com>");
113 MODULE_DESCRIPTION("Wacom protocol 4 serial tablet driver");
114 MODULE_LICENSE("GPL");
115
116 #define REQUEST_MODEL_AND_ROM_VERSION "~#"
117 #define REQUEST_MAX_COORDINATES "~C\r"
118 #define REQUEST_CONFIGURATION_STRING "~R\r"
119 #define REQUEST_RESET_TO_PROTOCOL_IV "\r#"
120 /*
121 * Note: sending "\r$\r" causes at least the Digitizer II to send
122 * packets in ASCII instead of binary. "\r#" seems to undo that.
123 */
124
125 #define COMMAND_START_SENDING_PACKETS "ST\r"
126 #define COMMAND_STOP_SENDING_PACKETS "SP\r"
127 #define COMMAND_MULTI_MODE_INPUT "MU1\r"
128 #define COMMAND_ORIGIN_IN_UPPER_LEFT "OC1\r"
129 #define COMMAND_ENABLE_ALL_MACRO_BUTTONS "~M0\r"
130 #define COMMAND_DISABLE_GROUP_1_MACRO_BUTTONS "~M1\r"
131 #define COMMAND_TRANSMIT_AT_MAX_RATE "IT0\r"
132 #define COMMAND_DISABLE_INCREMENTAL_MODE "IN0\r"
133 #define COMMAND_ENABLE_CONTINUOUS_MODE "SR\r"
134 #define COMMAND_ENABLE_PRESSURE_MODE "PH1\r"
135 #define COMMAND_Z_FILTER "ZF1\r"
136
137 /* Note that this is a protocol 4 packet without tilt information. */
138 #define PACKET_LENGTH 7
139 #define DATA_SIZE 32
140
141 /* flags */
142 #define F_COVERS_SCREEN 0x01
143 #define F_HAS_STYLUS2 0x02
144 #define F_HAS_SCROLLWHEEL 0x04
145
146 /* device IDs */
147 #define STYLUS_DEVICE_ID 0x02
148 #define CURSOR_DEVICE_ID 0x06
149 #define ERASER_DEVICE_ID 0x0A
150
151 enum { STYLUS = 1, ERASER, CURSOR };
152
153 static const struct {
154 int device_id;
155 int input_id;
156 } tools[] = {
157 { 0, 0 },
158 { STYLUS_DEVICE_ID, BTN_TOOL_PEN },
159 { ERASER_DEVICE_ID, BTN_TOOL_RUBBER },
160 { CURSOR_DEVICE_ID, BTN_TOOL_MOUSE },
161 };
162
163 struct wacom {
164 struct input_dev *dev;
165 struct completion cmd_done;
166 int result;
167 u8 expect;
168 u8 eraser_mask;
169 unsigned int extra_z_bits;
170 unsigned int flags;
171 unsigned int res_x, res_y;
172 unsigned int max_x, max_y;
173 unsigned int tool;
174 unsigned int idx;
175 u8 data[DATA_SIZE];
176 char phys[32];
177 };
178
179 enum {
180 MODEL_CINTIQ = 0x504C, /* PL */
181 MODEL_CINTIQ2 = 0x4454, /* DT */
182 MODEL_DIGITIZER_II = 0x5544, /* UD */
183 MODEL_GRAPHIRE = 0x4554, /* ET */
184 MODEL_PENPARTNER = 0x4354, /* CT */
185 MODEL_ARTPAD_II = 0x4B54, /* KT */
186 };
187
wacom_handle_model_response(struct wacom * wacom)188 static void wacom_handle_model_response(struct wacom *wacom)
189 {
190 int major_v, minor_v, r = 0;
191 char *p;
192
193 p = strrchr(wacom->data, 'V');
194 if (p)
195 r = sscanf(p + 1, "%u.%u", &major_v, &minor_v);
196 if (r != 2)
197 major_v = minor_v = 0;
198
199 switch (wacom->data[2] << 8 | wacom->data[3]) {
200 case MODEL_CINTIQ: /* UNTESTED */
201 case MODEL_CINTIQ2:
202 if ((wacom->data[2] << 8 | wacom->data[3]) == MODEL_CINTIQ) {
203 wacom->dev->name = "Wacom Cintiq";
204 wacom->dev->id.version = MODEL_CINTIQ;
205 } else {
206 wacom->dev->name = "Wacom Cintiq II";
207 wacom->dev->id.version = MODEL_CINTIQ2;
208 }
209 wacom->res_x = 508;
210 wacom->res_y = 508;
211
212 switch (wacom->data[5] << 8 | wacom->data[6]) {
213 case 0x3731: /* PL-710 */
214 wacom->res_x = 2540;
215 wacom->res_y = 2540;
216 fallthrough;
217 case 0x3535: /* PL-550 */
218 case 0x3830: /* PL-800 */
219 wacom->extra_z_bits = 2;
220 }
221
222 wacom->flags = F_COVERS_SCREEN;
223 break;
224
225 case MODEL_PENPARTNER:
226 wacom->dev->name = "Wacom Penpartner";
227 wacom->dev->id.version = MODEL_PENPARTNER;
228 wacom->res_x = 1000;
229 wacom->res_y = 1000;
230 break;
231
232 case MODEL_GRAPHIRE:
233 wacom->dev->name = "Wacom Graphire";
234 wacom->dev->id.version = MODEL_GRAPHIRE;
235 wacom->res_x = 1016;
236 wacom->res_y = 1016;
237 wacom->max_x = 5103;
238 wacom->max_y = 3711;
239 wacom->extra_z_bits = 2;
240 wacom->eraser_mask = 0x08;
241 wacom->flags = F_HAS_STYLUS2 | F_HAS_SCROLLWHEEL;
242 break;
243
244 case MODEL_ARTPAD_II:
245 case MODEL_DIGITIZER_II:
246 wacom->dev->name = "Wacom Digitizer II";
247 wacom->dev->id.version = MODEL_DIGITIZER_II;
248 if (major_v == 1 && minor_v <= 2)
249 wacom->extra_z_bits = 0; /* UNTESTED */
250 break;
251
252 default:
253 dev_err(&wacom->dev->dev, "Unsupported Wacom model %s\n",
254 wacom->data);
255 wacom->result = -ENODEV;
256 return;
257 }
258
259 dev_info(&wacom->dev->dev, "%s tablet, version %u.%u\n",
260 wacom->dev->name, major_v, minor_v);
261 }
262
wacom_handle_configuration_response(struct wacom * wacom)263 static void wacom_handle_configuration_response(struct wacom *wacom)
264 {
265 int r, skip;
266
267 dev_dbg(&wacom->dev->dev, "Configuration string: %s\n", wacom->data);
268 r = sscanf(wacom->data, "~R%x,%u,%u,%u,%u", &skip, &skip, &skip,
269 &wacom->res_x, &wacom->res_y);
270 if (r != 5)
271 dev_warn(&wacom->dev->dev, "could not get resolution\n");
272 }
273
wacom_handle_coordinates_response(struct wacom * wacom)274 static void wacom_handle_coordinates_response(struct wacom *wacom)
275 {
276 int r;
277
278 dev_dbg(&wacom->dev->dev, "Coordinates string: %s\n", wacom->data);
279 r = sscanf(wacom->data, "~C%u,%u", &wacom->max_x, &wacom->max_y);
280 if (r != 2)
281 dev_warn(&wacom->dev->dev, "could not get max coordinates\n");
282 }
283
wacom_handle_response(struct wacom * wacom)284 static void wacom_handle_response(struct wacom *wacom)
285 {
286 if (wacom->data[0] != '~' || wacom->data[1] != wacom->expect) {
287 dev_err(&wacom->dev->dev,
288 "Wacom got an unexpected response: %s\n", wacom->data);
289 wacom->result = -EIO;
290 } else {
291 wacom->result = 0;
292
293 switch (wacom->data[1]) {
294 case '#':
295 wacom_handle_model_response(wacom);
296 break;
297 case 'R':
298 wacom_handle_configuration_response(wacom);
299 break;
300 case 'C':
301 wacom_handle_coordinates_response(wacom);
302 break;
303 }
304 }
305
306 complete(&wacom->cmd_done);
307 }
308
wacom_handle_packet(struct wacom * wacom)309 static void wacom_handle_packet(struct wacom *wacom)
310 {
311 u8 in_proximity_p, stylus_p, button;
312 unsigned int tool;
313 int x, y, z;
314
315 in_proximity_p = wacom->data[0] & 0x40;
316 stylus_p = wacom->data[0] & 0x20;
317 button = (wacom->data[3] & 0x78) >> 3;
318 x = (wacom->data[0] & 3) << 14 | wacom->data[1]<<7 | wacom->data[2];
319 y = (wacom->data[3] & 3) << 14 | wacom->data[4]<<7 | wacom->data[5];
320
321 if (in_proximity_p && stylus_p) {
322 z = wacom->data[6] & 0x7f;
323 if (wacom->extra_z_bits >= 1)
324 z = z << 1 | (wacom->data[3] & 0x4) >> 2;
325 if (wacom->extra_z_bits > 1)
326 z = z << 1 | (wacom->data[0] & 0x4) >> 2;
327 z = z ^ (0x40 << wacom->extra_z_bits);
328 } else {
329 z = -1;
330 }
331
332 if (stylus_p)
333 tool = (button & wacom->eraser_mask) ? ERASER : STYLUS;
334 else
335 tool = CURSOR;
336
337 if (tool != wacom->tool && wacom->tool != 0) {
338 input_report_key(wacom->dev, tools[wacom->tool].input_id, 0);
339 input_sync(wacom->dev);
340 }
341 wacom->tool = tool;
342
343 input_report_key(wacom->dev, tools[tool].input_id, in_proximity_p);
344 input_report_abs(wacom->dev, ABS_MISC,
345 in_proximity_p ? tools[tool].device_id : 0);
346 input_report_abs(wacom->dev, ABS_X, x);
347 input_report_abs(wacom->dev, ABS_Y, y);
348 input_report_abs(wacom->dev, ABS_PRESSURE, z);
349 if (stylus_p) {
350 input_report_key(wacom->dev, BTN_TOUCH, button & 1);
351 input_report_key(wacom->dev, BTN_STYLUS, button & 2);
352 input_report_key(wacom->dev, BTN_STYLUS2, button & 4);
353 } else {
354 input_report_key(wacom->dev, BTN_LEFT, button & 1);
355 input_report_key(wacom->dev, BTN_RIGHT, button & 2);
356 input_report_key(wacom->dev, BTN_MIDDLE, button & 4);
357 /* handle relative wheel for non-stylus device */
358 z = (wacom->data[6] & 0x30) >> 4;
359 if (wacom->data[6] & 0x40)
360 z = -z;
361 input_report_rel(wacom->dev, REL_WHEEL, z);
362 }
363 input_sync(wacom->dev);
364 }
365
wacom_clear_data_buf(struct wacom * wacom)366 static void wacom_clear_data_buf(struct wacom *wacom)
367 {
368 memset(wacom->data, 0, DATA_SIZE);
369 wacom->idx = 0;
370 }
371
wacom_interrupt(struct serio * serio,unsigned char data,unsigned int flags)372 static irqreturn_t wacom_interrupt(struct serio *serio, unsigned char data,
373 unsigned int flags)
374 {
375 struct wacom *wacom = serio_get_drvdata(serio);
376
377 if (data & 0x80)
378 wacom->idx = 0;
379
380 /*
381 * We're either expecting a carriage return-terminated ASCII
382 * response string, or a seven-byte packet with the MSB set on
383 * the first byte.
384 *
385 * Note however that some tablets (the PenPartner, for
386 * example) don't send a carriage return at the end of a
387 * command. We handle these by waiting for timeout.
388 */
389 if (data == '\r' && !(wacom->data[0] & 0x80)) {
390 wacom_handle_response(wacom);
391 wacom_clear_data_buf(wacom);
392 return IRQ_HANDLED;
393 }
394
395 /* Leave place for 0 termination */
396 if (wacom->idx > (DATA_SIZE - 2)) {
397 dev_dbg(&wacom->dev->dev,
398 "throwing away %d bytes of garbage\n", wacom->idx);
399 wacom_clear_data_buf(wacom);
400 }
401 wacom->data[wacom->idx++] = data;
402
403 if (wacom->idx == PACKET_LENGTH && (wacom->data[0] & 0x80)) {
404 wacom_handle_packet(wacom);
405 wacom_clear_data_buf(wacom);
406 }
407
408 return IRQ_HANDLED;
409 }
410
wacom_disconnect(struct serio * serio)411 static void wacom_disconnect(struct serio *serio)
412 {
413 struct wacom *wacom = serio_get_drvdata(serio);
414
415 serio_close(serio);
416 serio_set_drvdata(serio, NULL);
417 input_unregister_device(wacom->dev);
418 kfree(wacom);
419 }
420
wacom_send(struct serio * serio,const u8 * command)421 static int wacom_send(struct serio *serio, const u8 *command)
422 {
423 int err = 0;
424
425 for (; !err && *command; command++)
426 err = serio_write(serio, *command);
427
428 return err;
429 }
430
wacom_send_setup_string(struct wacom * wacom,struct serio * serio)431 static int wacom_send_setup_string(struct wacom *wacom, struct serio *serio)
432 {
433 const u8 *cmd;
434
435 switch (wacom->dev->id.version) {
436 case MODEL_CINTIQ: /* UNTESTED */
437 cmd = COMMAND_ORIGIN_IN_UPPER_LEFT
438 COMMAND_TRANSMIT_AT_MAX_RATE
439 COMMAND_ENABLE_CONTINUOUS_MODE
440 COMMAND_START_SENDING_PACKETS;
441 break;
442
443 case MODEL_PENPARTNER:
444 cmd = COMMAND_ENABLE_PRESSURE_MODE
445 COMMAND_START_SENDING_PACKETS;
446 break;
447
448 default:
449 cmd = COMMAND_MULTI_MODE_INPUT
450 COMMAND_ORIGIN_IN_UPPER_LEFT
451 COMMAND_ENABLE_ALL_MACRO_BUTTONS
452 COMMAND_DISABLE_GROUP_1_MACRO_BUTTONS
453 COMMAND_TRANSMIT_AT_MAX_RATE
454 COMMAND_DISABLE_INCREMENTAL_MODE
455 COMMAND_ENABLE_CONTINUOUS_MODE
456 COMMAND_Z_FILTER
457 COMMAND_START_SENDING_PACKETS;
458 break;
459 }
460
461 return wacom_send(serio, cmd);
462 }
463
wacom_send_and_wait(struct wacom * wacom,struct serio * serio,const u8 * cmd,const char * desc)464 static int wacom_send_and_wait(struct wacom *wacom, struct serio *serio,
465 const u8 *cmd, const char *desc)
466 {
467 int err;
468 unsigned long u;
469
470 wacom->expect = cmd[1];
471 init_completion(&wacom->cmd_done);
472
473 err = wacom_send(serio, cmd);
474 if (err)
475 return err;
476
477 u = wait_for_completion_timeout(&wacom->cmd_done, HZ);
478 if (u == 0) {
479 /* Timeout, process what we've received. */
480 wacom_handle_response(wacom);
481 }
482
483 wacom->expect = 0;
484 return wacom->result;
485 }
486
wacom_setup(struct wacom * wacom,struct serio * serio)487 static int wacom_setup(struct wacom *wacom, struct serio *serio)
488 {
489 int err;
490
491 /* Note that setting the link speed is the job of inputattach.
492 * We assume that reset negotiation has already happened,
493 * here. */
494 err = wacom_send_and_wait(wacom, serio, REQUEST_MODEL_AND_ROM_VERSION,
495 "model and version");
496 if (err)
497 return err;
498
499 if (!(wacom->res_x && wacom->res_y)) {
500 err = wacom_send_and_wait(wacom, serio,
501 REQUEST_CONFIGURATION_STRING,
502 "configuration string");
503 if (err)
504 return err;
505 }
506
507 if (!(wacom->max_x && wacom->max_y)) {
508 err = wacom_send_and_wait(wacom, serio,
509 REQUEST_MAX_COORDINATES,
510 "coordinates string");
511 if (err)
512 return err;
513 }
514
515 return wacom_send_setup_string(wacom, serio);
516 }
517
wacom_connect(struct serio * serio,struct serio_driver * drv)518 static int wacom_connect(struct serio *serio, struct serio_driver *drv)
519 {
520 struct wacom *wacom;
521 struct input_dev *input_dev;
522 int err = -ENOMEM;
523
524 wacom = kzalloc(sizeof(*wacom), GFP_KERNEL);
525 input_dev = input_allocate_device();
526 if (!wacom || !input_dev)
527 goto free_device;
528
529 wacom->dev = input_dev;
530 wacom->extra_z_bits = 1;
531 wacom->eraser_mask = 0x04;
532 wacom->tool = wacom->idx = 0;
533 snprintf(wacom->phys, sizeof(wacom->phys), "%s/input0", serio->phys);
534 input_dev->phys = wacom->phys;
535 input_dev->id.bustype = BUS_RS232;
536 input_dev->id.vendor = SERIO_WACOM_IV;
537 input_dev->id.product = serio->id.extra;
538 input_dev->dev.parent = &serio->dev;
539
540 input_dev->evbit[0] =
541 BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) | BIT_MASK(EV_REL);
542 set_bit(ABS_MISC, input_dev->absbit);
543 set_bit(BTN_TOOL_PEN, input_dev->keybit);
544 set_bit(BTN_TOOL_RUBBER, input_dev->keybit);
545 set_bit(BTN_TOOL_MOUSE, input_dev->keybit);
546 set_bit(BTN_TOUCH, input_dev->keybit);
547 set_bit(BTN_STYLUS, input_dev->keybit);
548 set_bit(BTN_LEFT, input_dev->keybit);
549 set_bit(BTN_RIGHT, input_dev->keybit);
550 set_bit(BTN_MIDDLE, input_dev->keybit);
551
552 serio_set_drvdata(serio, wacom);
553
554 err = serio_open(serio, drv);
555 if (err)
556 goto free_device;
557
558 err = wacom_setup(wacom, serio);
559 if (err)
560 goto close_serio;
561
562 set_bit(INPUT_PROP_DIRECT, input_dev->propbit);
563 if (!(wacom->flags & F_COVERS_SCREEN))
564 __set_bit(INPUT_PROP_POINTER, input_dev->propbit);
565
566 if (wacom->flags & F_HAS_STYLUS2)
567 __set_bit(BTN_STYLUS2, input_dev->keybit);
568
569 if (wacom->flags & F_HAS_SCROLLWHEEL)
570 __set_bit(REL_WHEEL, input_dev->relbit);
571
572 input_abs_set_res(wacom->dev, ABS_X, wacom->res_x);
573 input_abs_set_res(wacom->dev, ABS_Y, wacom->res_y);
574 input_set_abs_params(wacom->dev, ABS_X, 0, wacom->max_x, 0, 0);
575 input_set_abs_params(wacom->dev, ABS_Y, 0, wacom->max_y, 0, 0);
576 input_set_abs_params(wacom->dev, ABS_PRESSURE, -1,
577 (1 << (7 + wacom->extra_z_bits)) - 1, 0, 0);
578
579 err = input_register_device(wacom->dev);
580 if (err)
581 goto close_serio;
582
583 return 0;
584
585 close_serio:
586 serio_close(serio);
587 free_device:
588 serio_set_drvdata(serio, NULL);
589 input_free_device(input_dev);
590 kfree(wacom);
591 return err;
592 }
593
594 static const struct serio_device_id wacom_serio_ids[] = {
595 {
596 .type = SERIO_RS232,
597 .proto = SERIO_WACOM_IV,
598 .id = SERIO_ANY,
599 .extra = SERIO_ANY,
600 },
601 { 0 }
602 };
603
604 MODULE_DEVICE_TABLE(serio, wacom_serio_ids);
605
606 static struct serio_driver wacom_drv = {
607 .driver = {
608 .name = "wacom_serial4",
609 },
610 .description = "Wacom protocol 4 serial tablet driver",
611 .id_table = wacom_serio_ids,
612 .interrupt = wacom_interrupt,
613 .connect = wacom_connect,
614 .disconnect = wacom_disconnect,
615 };
616
617 module_serio_driver(wacom_drv);
618