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