Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Stephen Evanchik <evanchsa@gmail.com>
4 *
5 * Trademarks are the property of their respective owners.
6 */
7
8#include <linux/array_size.h>
9#include <linux/slab.h>
10#include <linux/delay.h>
11#include <linux/serio.h>
12#include <linux/module.h>
13#include <linux/input.h>
14#include <linux/libps2.h>
15#include <linux/proc_fs.h>
16#include <linux/string.h>
17#include <linux/uaccess.h>
18#include "psmouse.h"
19#include "trackpoint.h"
20
21static const char * const trackpoint_variants[] = {
22 [TP_VARIANT_IBM] = "IBM",
23 [TP_VARIANT_ALPS] = "ALPS",
24 [TP_VARIANT_ELAN] = "Elan",
25 [TP_VARIANT_NXP] = "NXP",
26 [TP_VARIANT_JYT_SYNAPTICS] = "JYT_Synaptics",
27 [TP_VARIANT_SYNAPTICS] = "Synaptics",
28};
29
30/*
31 * Power-on Reset: Resets all trackpoint parameters, including RAM values,
32 * to defaults.
33 * Returns zero on success, non-zero on failure.
34 */
35static int trackpoint_power_on_reset(struct ps2dev *ps2dev)
36{
37 u8 param[2] = { TP_POR };
38 int err;
39
40 err = ps2_command(ps2dev, param, MAKE_PS2_CMD(1, 2, TP_COMMAND));
41 if (err)
42 return err;
43
44 /* Check for success response -- 0xAA00 */
45 if (param[0] != 0xAA || param[1] != 0x00)
46 return -ENODEV;
47
48 return 0;
49}
50
51/*
52 * Device IO: read, write and toggle bit
53 */
54static int trackpoint_read(struct ps2dev *ps2dev, u8 loc, u8 *results)
55{
56 results[0] = loc;
57
58 return ps2_command(ps2dev, results, MAKE_PS2_CMD(1, 1, TP_COMMAND));
59}
60
61static int trackpoint_write(struct ps2dev *ps2dev, u8 loc, u8 val)
62{
63 u8 param[3] = { TP_WRITE_MEM, loc, val };
64
65 return ps2_command(ps2dev, param, MAKE_PS2_CMD(3, 0, TP_COMMAND));
66}
67
68static int trackpoint_toggle_bit(struct ps2dev *ps2dev, u8 loc, u8 mask)
69{
70 u8 param[3] = { TP_TOGGLE, loc, mask };
71
72 /* Bad things will happen if the loc param isn't in this range */
73 if (loc < 0x20 || loc >= 0x2F)
74 return -EINVAL;
75
76 return ps2_command(ps2dev, param, MAKE_PS2_CMD(3, 0, TP_COMMAND));
77}
78
79static int trackpoint_update_bit(struct ps2dev *ps2dev,
80 u8 loc, u8 mask, u8 value)
81{
82 int retval;
83 u8 data;
84
85 retval = trackpoint_read(ps2dev, loc, &data);
86 if (retval)
87 return retval;
88
89 if (((data & mask) == mask) != !!value)
90 retval = trackpoint_toggle_bit(ps2dev, loc, mask);
91
92 return retval;
93}
94
95/*
96 * Trackpoint-specific attributes
97 */
98struct trackpoint_attr_data {
99 size_t field_offset;
100 u8 command;
101 u8 mask;
102 bool inverted;
103 u8 power_on_default;
104};
105
106static ssize_t trackpoint_show_int_attr(struct psmouse *psmouse,
107 void *data, char *buf)
108{
109 struct trackpoint_data *tp = psmouse->private;
110 struct trackpoint_attr_data *attr = data;
111 u8 value = *(u8 *)((void *)tp + attr->field_offset);
112
113 if (attr->inverted)
114 value = !value;
115
116 return sprintf(buf, "%u\n", value);
117}
118
119static ssize_t trackpoint_set_int_attr(struct psmouse *psmouse, void *data,
120 const char *buf, size_t count)
121{
122 struct trackpoint_data *tp = psmouse->private;
123 struct trackpoint_attr_data *attr = data;
124 u8 *field = (void *)tp + attr->field_offset;
125 u8 value;
126 int err;
127
128 err = kstrtou8(buf, 10, &value);
129 if (err)
130 return err;
131
132 *field = value;
133 err = trackpoint_write(&psmouse->ps2dev, attr->command, value);
134
135 return err ?: count;
136}
137
138#define TRACKPOINT_INT_ATTR(_name, _command, _default) \
139 static struct trackpoint_attr_data trackpoint_attr_##_name = { \
140 .field_offset = offsetof(struct trackpoint_data, _name), \
141 .command = _command, \
142 .power_on_default = _default, \
143 }; \
144 PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO, \
145 &trackpoint_attr_##_name, \
146 trackpoint_show_int_attr, trackpoint_set_int_attr)
147
148static ssize_t trackpoint_set_bit_attr(struct psmouse *psmouse, void *data,
149 const char *buf, size_t count)
150{
151 struct trackpoint_data *tp = psmouse->private;
152 struct trackpoint_attr_data *attr = data;
153 bool *field = (void *)tp + attr->field_offset;
154 bool value;
155 int err;
156
157 err = kstrtobool(buf, &value);
158 if (err)
159 return err;
160
161 if (attr->inverted)
162 value = !value;
163
164 if (*field != value) {
165 *field = value;
166 err = trackpoint_toggle_bit(&psmouse->ps2dev,
167 attr->command, attr->mask);
168 }
169
170 return err ?: count;
171}
172
173
174#define TRACKPOINT_BIT_ATTR(_name, _command, _mask, _inv, _default) \
175static struct trackpoint_attr_data trackpoint_attr_##_name = { \
176 .field_offset = offsetof(struct trackpoint_data, \
177 _name), \
178 .command = _command, \
179 .mask = _mask, \
180 .inverted = _inv, \
181 .power_on_default = _default, \
182 }; \
183PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO, \
184 &trackpoint_attr_##_name, \
185 trackpoint_show_int_attr, trackpoint_set_bit_attr)
186
187TRACKPOINT_INT_ATTR(sensitivity, TP_SENS, TP_DEF_SENS);
188TRACKPOINT_INT_ATTR(speed, TP_SPEED, TP_DEF_SPEED);
189TRACKPOINT_INT_ATTR(inertia, TP_INERTIA, TP_DEF_INERTIA);
190TRACKPOINT_INT_ATTR(reach, TP_REACH, TP_DEF_REACH);
191TRACKPOINT_INT_ATTR(draghys, TP_DRAGHYS, TP_DEF_DRAGHYS);
192TRACKPOINT_INT_ATTR(mindrag, TP_MINDRAG, TP_DEF_MINDRAG);
193TRACKPOINT_INT_ATTR(thresh, TP_THRESH, TP_DEF_THRESH);
194TRACKPOINT_INT_ATTR(upthresh, TP_UP_THRESH, TP_DEF_UP_THRESH);
195TRACKPOINT_INT_ATTR(ztime, TP_Z_TIME, TP_DEF_Z_TIME);
196TRACKPOINT_INT_ATTR(jenks, TP_JENKS_CURV, TP_DEF_JENKS_CURV);
197TRACKPOINT_INT_ATTR(drift_time, TP_DRIFT_TIME, TP_DEF_DRIFT_TIME);
198
199TRACKPOINT_BIT_ATTR(press_to_select, TP_TOGGLE_PTSON, TP_MASK_PTSON, false,
200 TP_DEF_PTSON);
201TRACKPOINT_BIT_ATTR(skipback, TP_TOGGLE_SKIPBACK, TP_MASK_SKIPBACK, false,
202 TP_DEF_SKIPBACK);
203TRACKPOINT_BIT_ATTR(ext_dev, TP_TOGGLE_EXT_DEV, TP_MASK_EXT_DEV, true,
204 TP_DEF_EXT_DEV);
205
206static bool trackpoint_is_attr_available(struct psmouse *psmouse,
207 struct attribute *attr)
208{
209 struct trackpoint_data *tp = psmouse->private;
210
211 return tp->variant_id == TP_VARIANT_IBM ||
212 attr == &psmouse_attr_sensitivity.dattr.attr ||
213 attr == &psmouse_attr_press_to_select.dattr.attr;
214}
215
216static umode_t trackpoint_is_attr_visible(struct kobject *kobj,
217 struct attribute *attr, int n)
218{
219 struct device *dev = kobj_to_dev(kobj);
220 struct serio *serio = to_serio_port(dev);
221 struct psmouse *psmouse = psmouse_from_serio(serio);
222
223 return trackpoint_is_attr_available(psmouse, attr) ? attr->mode : 0;
224}
225
226static struct attribute *trackpoint_attrs[] = {
227 &psmouse_attr_sensitivity.dattr.attr,
228 &psmouse_attr_speed.dattr.attr,
229 &psmouse_attr_inertia.dattr.attr,
230 &psmouse_attr_reach.dattr.attr,
231 &psmouse_attr_draghys.dattr.attr,
232 &psmouse_attr_mindrag.dattr.attr,
233 &psmouse_attr_thresh.dattr.attr,
234 &psmouse_attr_upthresh.dattr.attr,
235 &psmouse_attr_ztime.dattr.attr,
236 &psmouse_attr_jenks.dattr.attr,
237 &psmouse_attr_drift_time.dattr.attr,
238 &psmouse_attr_press_to_select.dattr.attr,
239 &psmouse_attr_skipback.dattr.attr,
240 &psmouse_attr_ext_dev.dattr.attr,
241 NULL
242};
243
244static struct attribute_group trackpoint_attr_group = {
245 .is_visible = trackpoint_is_attr_visible,
246 .attrs = trackpoint_attrs,
247};
248
249#define TRACKPOINT_UPDATE(_power_on, _psmouse, _tp, _name) \
250do { \
251 struct trackpoint_attr_data *_attr = &trackpoint_attr_##_name; \
252 \
253 if ((!_power_on || _tp->_name != _attr->power_on_default) && \
254 trackpoint_is_attr_available(_psmouse, \
255 &psmouse_attr_##_name.dattr.attr)) { \
256 if (!_attr->mask) \
257 trackpoint_write(&_psmouse->ps2dev, \
258 _attr->command, _tp->_name); \
259 else \
260 trackpoint_update_bit(&_psmouse->ps2dev, \
261 _attr->command, _attr->mask, \
262 _tp->_name); \
263 } \
264} while (0)
265
266#define TRACKPOINT_SET_POWER_ON_DEFAULT(_tp, _name) \
267do { \
268 _tp->_name = trackpoint_attr_##_name.power_on_default; \
269} while (0)
270
271static int trackpoint_start_protocol(struct psmouse *psmouse,
272 u8 *variant_id, u8 *firmware_id)
273{
274 u8 param[2] = { 0 };
275 int error;
276
277 error = ps2_command(&psmouse->ps2dev,
278 param, MAKE_PS2_CMD(0, 2, TP_READ_ID));
279 if (error)
280 return error;
281
282 switch (param[0]) {
283 case TP_VARIANT_IBM:
284 case TP_VARIANT_ALPS:
285 case TP_VARIANT_ELAN:
286 case TP_VARIANT_NXP:
287 case TP_VARIANT_JYT_SYNAPTICS:
288 case TP_VARIANT_SYNAPTICS:
289 if (variant_id)
290 *variant_id = param[0];
291 if (firmware_id)
292 *firmware_id = param[1];
293 return 0;
294 }
295
296 return -ENODEV;
297}
298
299/*
300 * Write parameters to trackpad.
301 * in_power_on_state: Set to true if TP is in default / power-on state (ex. if
302 * power-on reset was run). If so, values will only be
303 * written to TP if they differ from power-on default.
304 */
305static int trackpoint_sync(struct psmouse *psmouse, bool in_power_on_state)
306{
307 struct trackpoint_data *tp = psmouse->private;
308
309 if (!in_power_on_state && tp->variant_id == TP_VARIANT_IBM) {
310 /*
311 * Disable features that may make device unusable
312 * with this driver.
313 */
314 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_TWOHAND,
315 TP_MASK_TWOHAND, TP_DEF_TWOHAND);
316
317 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_SOURCE_TAG,
318 TP_MASK_SOURCE_TAG, TP_DEF_SOURCE_TAG);
319
320 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_MB,
321 TP_MASK_MB, TP_DEF_MB);
322 }
323
324 /*
325 * These properties can be changed in this driver. Only
326 * configure them if the values are non-default or if the TP is in
327 * an unknown state.
328 */
329 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, sensitivity);
330 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, inertia);
331 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, speed);
332 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, reach);
333 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, draghys);
334 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, mindrag);
335 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, thresh);
336 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, upthresh);
337 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ztime);
338 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, jenks);
339 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, drift_time);
340
341 /* toggles */
342 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, press_to_select);
343 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, skipback);
344 TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ext_dev);
345
346 return 0;
347}
348
349static void trackpoint_defaults(struct trackpoint_data *tp)
350{
351 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, sensitivity);
352 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, speed);
353 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, reach);
354 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, draghys);
355 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, mindrag);
356 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, thresh);
357 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, upthresh);
358 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ztime);
359 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, jenks);
360 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, drift_time);
361 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, inertia);
362
363 /* toggles */
364 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, press_to_select);
365 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, skipback);
366 TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ext_dev);
367}
368
369static void trackpoint_disconnect(struct psmouse *psmouse)
370{
371 device_remove_group(&psmouse->ps2dev.serio->dev,
372 &trackpoint_attr_group);
373
374 kfree(psmouse->private);
375 psmouse->private = NULL;
376}
377
378static int trackpoint_reconnect(struct psmouse *psmouse)
379{
380 struct trackpoint_data *tp = psmouse->private;
381 int error;
382 bool was_reset;
383
384 error = trackpoint_start_protocol(psmouse, NULL, NULL);
385 if (error)
386 return error;
387
388 was_reset = tp->variant_id == TP_VARIANT_IBM &&
389 trackpoint_power_on_reset(&psmouse->ps2dev) == 0;
390
391 error = trackpoint_sync(psmouse, was_reset);
392 if (error)
393 return error;
394
395 return 0;
396}
397
398/* List of known incapable device PNP IDs */
399static const char * const dt_incompatible_devices[] = {
400 "LEN0304",
401 "LEN0306",
402 "LEN0317",
403 "LEN031A",
404 "LEN031B",
405 "LEN031C",
406 "LEN031D",
407};
408
409/*
410 * Checks if it's a doubletap capable device.
411 * The PNP ID format is "PNP: LEN030d PNP0f13".
412 */
413static bool trackpoint_is_dt_capable(const char *pnp_id)
414{
415 size_t i;
416
417 if (!pnp_id)
418 return false;
419
420 /* Must start with "PNP: LEN03" */
421 if (!strstarts(pnp_id, "PNP: LEN03"))
422 return false;
423
424 /* Ensure enough length before comparing */
425 if (strlen(pnp_id) < 12)
426 return false;
427
428 /* Check deny-list */
429 for (i = 0; i < ARRAY_SIZE(dt_incompatible_devices); i++) {
430 if (!strncmp(pnp_id + 5, dt_incompatible_devices[i], 7))
431 return false;
432 }
433 return true;
434}
435
436int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
437{
438 struct ps2dev *ps2dev = &psmouse->ps2dev;
439 struct trackpoint_data *tp;
440 u8 variant_id;
441 u8 firmware_id;
442 u8 button_info;
443 int error;
444
445 error = trackpoint_start_protocol(psmouse, &variant_id, &firmware_id);
446 if (error)
447 return error;
448
449 if (!set_properties)
450 return 0;
451
452 tp = kzalloc_obj(*tp);
453 if (!tp)
454 return -ENOMEM;
455
456 trackpoint_defaults(tp);
457 tp->variant_id = variant_id;
458 tp->firmware_id = firmware_id;
459
460 psmouse->private = tp;
461
462 psmouse->vendor = trackpoint_variants[variant_id];
463 psmouse->name = "TrackPoint";
464
465 psmouse->reconnect = trackpoint_reconnect;
466 psmouse->disconnect = trackpoint_disconnect;
467
468 if (variant_id != TP_VARIANT_IBM) {
469 /* Newer variants do not support extended button query. */
470 button_info = 0x33;
471 } else {
472 error = trackpoint_read(ps2dev, TP_EXT_BTN, &button_info);
473 if (error) {
474 psmouse_warn(psmouse,
475 "failed to get extended button data, assuming 3 buttons\n");
476 button_info = 0x33;
477 } else if (!button_info) {
478 psmouse_warn(psmouse,
479 "got 0 in extended button data, assuming 3 buttons\n");
480 button_info = 0x33;
481 }
482 }
483
484 if ((button_info & 0x0f) >= 3)
485 input_set_capability(psmouse->dev, EV_KEY, BTN_MIDDLE);
486
487 __set_bit(INPUT_PROP_POINTER, psmouse->dev->propbit);
488 __set_bit(INPUT_PROP_POINTING_STICK, psmouse->dev->propbit);
489
490 if (variant_id != TP_VARIANT_IBM ||
491 trackpoint_power_on_reset(ps2dev) != 0) {
492 /*
493 * Write defaults to TP if we did not reset the trackpoint.
494 */
495 trackpoint_sync(psmouse, false);
496 }
497
498 error = device_add_group(&ps2dev->serio->dev, &trackpoint_attr_group);
499 if (error) {
500 psmouse_err(psmouse,
501 "failed to create sysfs attributes, error: %d\n",
502 error);
503 kfree(psmouse->private);
504 psmouse->private = NULL;
505 return -1;
506 }
507
508 psmouse_info(psmouse,
509 "%s TrackPoint firmware: 0x%02x, buttons: %d/%d\n",
510 psmouse->vendor, firmware_id,
511 (button_info & 0xf0) >> 4, button_info & 0x0f);
512
513 if (trackpoint_is_dt_capable(ps2dev->serio->firmware_id)) {
514 error = trackpoint_write(ps2dev, TP_DOUBLETAP, TP_DOUBLETAP_ENABLE);
515 if (error)
516 psmouse_warn(psmouse, "Failed to enable doubletap: %d\n", error);
517 }
518
519 return 0;
520}
521