xref: /openbmc/linux/drivers/input/mouse/trackpoint.c (revision b34e08d5)
1 /*
2  * Stephen Evanchik <evanchsa@gmail.com>
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License version 2 as published by
6  * the Free Software Foundation.
7  *
8  * Trademarks are the property of their respective owners.
9  */
10 
11 #include <linux/slab.h>
12 #include <linux/delay.h>
13 #include <linux/serio.h>
14 #include <linux/module.h>
15 #include <linux/input.h>
16 #include <linux/libps2.h>
17 #include <linux/proc_fs.h>
18 #include <asm/uaccess.h>
19 #include "psmouse.h"
20 #include "trackpoint.h"
21 
22 /*
23  * Power-on Reset: Resets all trackpoint parameters, including RAM values,
24  * to defaults.
25  * Returns zero on success, non-zero on failure.
26  */
27 static int trackpoint_power_on_reset(struct ps2dev *ps2dev)
28 {
29 	unsigned char results[2];
30 	int tries = 0;
31 
32 	/* Issue POR command, and repeat up to once if 0xFC00 received */
33 	do {
34 		if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
35 		    ps2_command(ps2dev, results, MAKE_PS2_CMD(0, 2, TP_POR)))
36 			return -1;
37 	} while (results[0] == 0xFC && results[1] == 0x00 && ++tries < 2);
38 
39 	/* Check for success response -- 0xAA00 */
40 	if (results[0] != 0xAA || results[1] != 0x00)
41 		return -1;
42 
43 	return 0;
44 }
45 
46 /*
47  * Device IO: read, write and toggle bit
48  */
49 static int trackpoint_read(struct ps2dev *ps2dev,
50 			   unsigned char loc, unsigned char *results)
51 {
52 	if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
53 	    ps2_command(ps2dev, results, MAKE_PS2_CMD(0, 1, loc))) {
54 		return -1;
55 	}
56 
57 	return 0;
58 }
59 
60 static int trackpoint_write(struct ps2dev *ps2dev,
61 			    unsigned char loc, unsigned char val)
62 {
63 	if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
64 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_WRITE_MEM)) ||
65 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, loc)) ||
66 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, val))) {
67 		return -1;
68 	}
69 
70 	return 0;
71 }
72 
73 static int trackpoint_toggle_bit(struct ps2dev *ps2dev,
74 				 unsigned char loc, unsigned char mask)
75 {
76 	/* Bad things will happen if the loc param isn't in this range */
77 	if (loc < 0x20 || loc >= 0x2F)
78 		return -1;
79 
80 	if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
81 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_TOGGLE)) ||
82 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, loc)) ||
83 	    ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, mask))) {
84 		return -1;
85 	}
86 
87 	return 0;
88 }
89 
90 static int trackpoint_update_bit(struct ps2dev *ps2dev, unsigned char loc,
91 				 unsigned char mask, unsigned char value)
92 {
93 	int retval = 0;
94 	unsigned char data;
95 
96 	trackpoint_read(ps2dev, loc, &data);
97 	if (((data & mask) == mask) != !!value)
98 		retval = trackpoint_toggle_bit(ps2dev, loc, mask);
99 
100 	return retval;
101 }
102 
103 /*
104  * Trackpoint-specific attributes
105  */
106 struct trackpoint_attr_data {
107 	size_t field_offset;
108 	unsigned char command;
109 	unsigned char mask;
110 	unsigned char inverted;
111 	unsigned char power_on_default;
112 };
113 
114 static ssize_t trackpoint_show_int_attr(struct psmouse *psmouse, void *data, char *buf)
115 {
116 	struct trackpoint_data *tp = psmouse->private;
117 	struct trackpoint_attr_data *attr = data;
118 	unsigned char value = *(unsigned char *)((char *)tp + attr->field_offset);
119 
120 	if (attr->inverted)
121 		value = !value;
122 
123 	return sprintf(buf, "%u\n", value);
124 }
125 
126 static ssize_t trackpoint_set_int_attr(struct psmouse *psmouse, void *data,
127 					const char *buf, size_t count)
128 {
129 	struct trackpoint_data *tp = psmouse->private;
130 	struct trackpoint_attr_data *attr = data;
131 	unsigned char *field = (unsigned char *)((char *)tp + attr->field_offset);
132 	unsigned char value;
133 	int err;
134 
135 	err = kstrtou8(buf, 10, &value);
136 	if (err)
137 		return err;
138 
139 	*field = value;
140 	trackpoint_write(&psmouse->ps2dev, attr->command, value);
141 
142 	return count;
143 }
144 
145 #define TRACKPOINT_INT_ATTR(_name, _command, _default)				\
146 	static struct trackpoint_attr_data trackpoint_attr_##_name = {		\
147 		.field_offset = offsetof(struct trackpoint_data, _name),	\
148 		.command = _command,						\
149 		.power_on_default = _default,					\
150 	};									\
151 	PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,				\
152 			    &trackpoint_attr_##_name,				\
153 			    trackpoint_show_int_attr, trackpoint_set_int_attr)
154 
155 static ssize_t trackpoint_set_bit_attr(struct psmouse *psmouse, void *data,
156 					const char *buf, size_t count)
157 {
158 	struct trackpoint_data *tp = psmouse->private;
159 	struct trackpoint_attr_data *attr = data;
160 	unsigned char *field = (unsigned char *)((char *)tp + attr->field_offset);
161 	unsigned int value;
162 	int err;
163 
164 	err = kstrtouint(buf, 10, &value);
165 	if (err)
166 		return err;
167 
168 	if (value > 1)
169 		return -EINVAL;
170 
171 	if (attr->inverted)
172 		value = !value;
173 
174 	if (*field != value) {
175 		*field = value;
176 		trackpoint_toggle_bit(&psmouse->ps2dev, attr->command, attr->mask);
177 	}
178 
179 	return count;
180 }
181 
182 
183 #define TRACKPOINT_BIT_ATTR(_name, _command, _mask, _inv, _default)	\
184 static struct trackpoint_attr_data trackpoint_attr_##_name = {		\
185 	.field_offset		= offsetof(struct trackpoint_data,	\
186 					   _name),			\
187 	.command		= _command,				\
188 	.mask			= _mask,				\
189 	.inverted		= _inv,					\
190 	.power_on_default	= _default,				\
191 	};								\
192 PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,				\
193 		    &trackpoint_attr_##_name,				\
194 		    trackpoint_show_int_attr, trackpoint_set_bit_attr)
195 
196 #define TRACKPOINT_UPDATE_BIT(_psmouse, _tp, _name)			\
197 do {									\
198 	struct trackpoint_attr_data *_attr = &trackpoint_attr_##_name;	\
199 									\
200 	trackpoint_update_bit(&_psmouse->ps2dev,			\
201 			_attr->command, _attr->mask, _tp->_name);	\
202 } while (0)
203 
204 #define TRACKPOINT_UPDATE(_power_on, _psmouse, _tp, _name)		\
205 do {									\
206 	if (!_power_on ||						\
207 	    _tp->_name != trackpoint_attr_##_name.power_on_default) {	\
208 		if (!trackpoint_attr_##_name.mask)			\
209 			trackpoint_write(&_psmouse->ps2dev,		\
210 				 trackpoint_attr_##_name.command,	\
211 				 _tp->_name);				\
212 		else							\
213 			TRACKPOINT_UPDATE_BIT(_psmouse, _tp, _name);	\
214 	}								\
215 } while (0)
216 
217 #define TRACKPOINT_SET_POWER_ON_DEFAULT(_tp, _name)				\
218 	(_tp->_name = trackpoint_attr_##_name.power_on_default)
219 
220 TRACKPOINT_INT_ATTR(sensitivity, TP_SENS, TP_DEF_SENS);
221 TRACKPOINT_INT_ATTR(speed, TP_SPEED, TP_DEF_SPEED);
222 TRACKPOINT_INT_ATTR(inertia, TP_INERTIA, TP_DEF_INERTIA);
223 TRACKPOINT_INT_ATTR(reach, TP_REACH, TP_DEF_REACH);
224 TRACKPOINT_INT_ATTR(draghys, TP_DRAGHYS, TP_DEF_DRAGHYS);
225 TRACKPOINT_INT_ATTR(mindrag, TP_MINDRAG, TP_DEF_MINDRAG);
226 TRACKPOINT_INT_ATTR(thresh, TP_THRESH, TP_DEF_THRESH);
227 TRACKPOINT_INT_ATTR(upthresh, TP_UP_THRESH, TP_DEF_UP_THRESH);
228 TRACKPOINT_INT_ATTR(ztime, TP_Z_TIME, TP_DEF_Z_TIME);
229 TRACKPOINT_INT_ATTR(jenks, TP_JENKS_CURV, TP_DEF_JENKS_CURV);
230 
231 TRACKPOINT_BIT_ATTR(press_to_select, TP_TOGGLE_PTSON, TP_MASK_PTSON, 0,
232 		    TP_DEF_PTSON);
233 TRACKPOINT_BIT_ATTR(skipback, TP_TOGGLE_SKIPBACK, TP_MASK_SKIPBACK, 0,
234 		    TP_DEF_SKIPBACK);
235 TRACKPOINT_BIT_ATTR(ext_dev, TP_TOGGLE_EXT_DEV, TP_MASK_EXT_DEV, 1,
236 		    TP_DEF_EXT_DEV);
237 
238 static struct attribute *trackpoint_attrs[] = {
239 	&psmouse_attr_sensitivity.dattr.attr,
240 	&psmouse_attr_speed.dattr.attr,
241 	&psmouse_attr_inertia.dattr.attr,
242 	&psmouse_attr_reach.dattr.attr,
243 	&psmouse_attr_draghys.dattr.attr,
244 	&psmouse_attr_mindrag.dattr.attr,
245 	&psmouse_attr_thresh.dattr.attr,
246 	&psmouse_attr_upthresh.dattr.attr,
247 	&psmouse_attr_ztime.dattr.attr,
248 	&psmouse_attr_jenks.dattr.attr,
249 	&psmouse_attr_press_to_select.dattr.attr,
250 	&psmouse_attr_skipback.dattr.attr,
251 	&psmouse_attr_ext_dev.dattr.attr,
252 	NULL
253 };
254 
255 static struct attribute_group trackpoint_attr_group = {
256 	.attrs = trackpoint_attrs,
257 };
258 
259 static int trackpoint_start_protocol(struct psmouse *psmouse, unsigned char *firmware_id)
260 {
261 	unsigned char param[2] = { 0 };
262 
263 	if (ps2_command(&psmouse->ps2dev, param, MAKE_PS2_CMD(0, 2, TP_READ_ID)))
264 		return -1;
265 
266 	if (param[0] != TP_MAGIC_IDENT)
267 		return -1;
268 
269 	if (firmware_id)
270 		*firmware_id = param[1];
271 
272 	return 0;
273 }
274 
275 /*
276  * Write parameters to trackpad.
277  * in_power_on_state: Set to true if TP is in default / power-on state (ex. if
278  *		      power-on reset was run). If so, values will only be
279  *		      written to TP if they differ from power-on default.
280  */
281 static int trackpoint_sync(struct psmouse *psmouse, bool in_power_on_state)
282 {
283 	struct trackpoint_data *tp = psmouse->private;
284 
285 	if (!in_power_on_state) {
286 		/*
287 		 * Disable features that may make device unusable
288 		 * with this driver.
289 		 */
290 		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_TWOHAND,
291 				      TP_MASK_TWOHAND, TP_DEF_TWOHAND);
292 
293 		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_SOURCE_TAG,
294 				      TP_MASK_SOURCE_TAG, TP_DEF_SOURCE_TAG);
295 
296 		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_MB,
297 				      TP_MASK_MB, TP_DEF_MB);
298 	}
299 
300 	/*
301 	 * These properties can be changed in this driver. Only
302 	 * configure them if the values are non-default or if the TP is in
303 	 * an unknown state.
304 	 */
305 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, sensitivity);
306 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, inertia);
307 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, speed);
308 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, reach);
309 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, draghys);
310 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, mindrag);
311 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, thresh);
312 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, upthresh);
313 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ztime);
314 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, jenks);
315 
316 	/* toggles */
317 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, press_to_select);
318 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, skipback);
319 	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ext_dev);
320 
321 	return 0;
322 }
323 
324 static void trackpoint_defaults(struct trackpoint_data *tp)
325 {
326 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, sensitivity);
327 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, speed);
328 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, reach);
329 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, draghys);
330 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, mindrag);
331 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, thresh);
332 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, upthresh);
333 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ztime);
334 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, jenks);
335 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, inertia);
336 
337 	/* toggles */
338 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, press_to_select);
339 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, skipback);
340 	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ext_dev);
341 }
342 
343 static void trackpoint_disconnect(struct psmouse *psmouse)
344 {
345 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj, &trackpoint_attr_group);
346 
347 	kfree(psmouse->private);
348 	psmouse->private = NULL;
349 }
350 
351 static int trackpoint_reconnect(struct psmouse *psmouse)
352 {
353 	int reset_fail;
354 
355 	if (trackpoint_start_protocol(psmouse, NULL))
356 		return -1;
357 
358 	reset_fail = trackpoint_power_on_reset(&psmouse->ps2dev);
359 	if (trackpoint_sync(psmouse, !reset_fail))
360 		return -1;
361 
362 	return 0;
363 }
364 
365 int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
366 {
367 	struct ps2dev *ps2dev = &psmouse->ps2dev;
368 	unsigned char firmware_id;
369 	unsigned char button_info;
370 	int error;
371 
372 	if (trackpoint_start_protocol(psmouse, &firmware_id))
373 		return -1;
374 
375 	if (!set_properties)
376 		return 0;
377 
378 	if (trackpoint_read(&psmouse->ps2dev, TP_EXT_BTN, &button_info)) {
379 		psmouse_warn(psmouse, "failed to get extended button data\n");
380 		button_info = 0;
381 	}
382 
383 	psmouse->private = kzalloc(sizeof(struct trackpoint_data), GFP_KERNEL);
384 	if (!psmouse->private)
385 		return -ENOMEM;
386 
387 	psmouse->vendor = "IBM";
388 	psmouse->name = "TrackPoint";
389 
390 	psmouse->reconnect = trackpoint_reconnect;
391 	psmouse->disconnect = trackpoint_disconnect;
392 
393 	if ((button_info & 0x0f) >= 3)
394 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
395 
396 	trackpoint_defaults(psmouse->private);
397 
398 	error = trackpoint_power_on_reset(&psmouse->ps2dev);
399 
400 	/* Write defaults to TP only if reset fails. */
401 	if (error)
402 		trackpoint_sync(psmouse, false);
403 
404 	error = sysfs_create_group(&ps2dev->serio->dev.kobj, &trackpoint_attr_group);
405 	if (error) {
406 		psmouse_err(psmouse,
407 			    "failed to create sysfs attributes, error: %d\n",
408 			    error);
409 		kfree(psmouse->private);
410 		psmouse->private = NULL;
411 		return -1;
412 	}
413 
414 	psmouse_info(psmouse,
415 		     "IBM TrackPoint firmware: 0x%02x, buttons: %d/%d\n",
416 		     firmware_id,
417 		     (button_info & 0xf0) >> 4, button_info & 0x0f);
418 
419 	return 0;
420 }
421 
422