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