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 */
27static 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 */
49static 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
60static 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
73static 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
90static 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 */
106struct 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
114static 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
126static 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
155static 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)	\
184static 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	};								\
192PSMOUSE_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)			\
197do {									\
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)		\
205do {									\
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
220TRACKPOINT_INT_ATTR(sensitivity, TP_SENS, TP_DEF_SENS);
221TRACKPOINT_INT_ATTR(speed, TP_SPEED, TP_DEF_SPEED);
222TRACKPOINT_INT_ATTR(inertia, TP_INERTIA, TP_DEF_INERTIA);
223TRACKPOINT_INT_ATTR(reach, TP_REACH, TP_DEF_REACH);
224TRACKPOINT_INT_ATTR(draghys, TP_DRAGHYS, TP_DEF_DRAGHYS);
225TRACKPOINT_INT_ATTR(mindrag, TP_MINDRAG, TP_DEF_MINDRAG);
226TRACKPOINT_INT_ATTR(thresh, TP_THRESH, TP_DEF_THRESH);
227TRACKPOINT_INT_ATTR(upthresh, TP_UP_THRESH, TP_DEF_UP_THRESH);
228TRACKPOINT_INT_ATTR(ztime, TP_Z_TIME, TP_DEF_Z_TIME);
229TRACKPOINT_INT_ATTR(jenks, TP_JENKS_CURV, TP_DEF_JENKS_CURV);
230TRACKPOINT_INT_ATTR(drift_time, TP_DRIFT_TIME, TP_DEF_DRIFT_TIME);
231
232TRACKPOINT_BIT_ATTR(press_to_select, TP_TOGGLE_PTSON, TP_MASK_PTSON, 0,
233		    TP_DEF_PTSON);
234TRACKPOINT_BIT_ATTR(skipback, TP_TOGGLE_SKIPBACK, TP_MASK_SKIPBACK, 0,
235		    TP_DEF_SKIPBACK);
236TRACKPOINT_BIT_ATTR(ext_dev, TP_TOGGLE_EXT_DEV, TP_MASK_EXT_DEV, 1,
237		    TP_DEF_EXT_DEV);
238
239static struct attribute *trackpoint_attrs[] = {
240	&psmouse_attr_sensitivity.dattr.attr,
241	&psmouse_attr_speed.dattr.attr,
242	&psmouse_attr_inertia.dattr.attr,
243	&psmouse_attr_reach.dattr.attr,
244	&psmouse_attr_draghys.dattr.attr,
245	&psmouse_attr_mindrag.dattr.attr,
246	&psmouse_attr_thresh.dattr.attr,
247	&psmouse_attr_upthresh.dattr.attr,
248	&psmouse_attr_ztime.dattr.attr,
249	&psmouse_attr_jenks.dattr.attr,
250	&psmouse_attr_drift_time.dattr.attr,
251	&psmouse_attr_press_to_select.dattr.attr,
252	&psmouse_attr_skipback.dattr.attr,
253	&psmouse_attr_ext_dev.dattr.attr,
254	NULL
255};
256
257static struct attribute_group trackpoint_attr_group = {
258	.attrs = trackpoint_attrs,
259};
260
261static int trackpoint_start_protocol(struct psmouse *psmouse, unsigned char *firmware_id)
262{
263	unsigned char param[2] = { 0 };
264
265	if (ps2_command(&psmouse->ps2dev, param, MAKE_PS2_CMD(0, 2, TP_READ_ID)))
266		return -1;
267
268	if (param[0] != TP_MAGIC_IDENT)
269		return -1;
270
271	if (firmware_id)
272		*firmware_id = param[1];
273
274	return 0;
275}
276
277/*
278 * Write parameters to trackpad.
279 * in_power_on_state: Set to true if TP is in default / power-on state (ex. if
280 *		      power-on reset was run). If so, values will only be
281 *		      written to TP if they differ from power-on default.
282 */
283static int trackpoint_sync(struct psmouse *psmouse, bool in_power_on_state)
284{
285	struct trackpoint_data *tp = psmouse->private;
286
287	if (!in_power_on_state) {
288		/*
289		 * Disable features that may make device unusable
290		 * with this driver.
291		 */
292		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_TWOHAND,
293				      TP_MASK_TWOHAND, TP_DEF_TWOHAND);
294
295		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_SOURCE_TAG,
296				      TP_MASK_SOURCE_TAG, TP_DEF_SOURCE_TAG);
297
298		trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_MB,
299				      TP_MASK_MB, TP_DEF_MB);
300	}
301
302	/*
303	 * These properties can be changed in this driver. Only
304	 * configure them if the values are non-default or if the TP is in
305	 * an unknown state.
306	 */
307	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, sensitivity);
308	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, inertia);
309	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, speed);
310	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, reach);
311	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, draghys);
312	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, mindrag);
313	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, thresh);
314	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, upthresh);
315	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ztime);
316	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, jenks);
317	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, drift_time);
318
319	/* toggles */
320	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, press_to_select);
321	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, skipback);
322	TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ext_dev);
323
324	return 0;
325}
326
327static void trackpoint_defaults(struct trackpoint_data *tp)
328{
329	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, sensitivity);
330	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, speed);
331	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, reach);
332	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, draghys);
333	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, mindrag);
334	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, thresh);
335	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, upthresh);
336	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ztime);
337	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, jenks);
338	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, drift_time);
339	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, inertia);
340
341	/* toggles */
342	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, press_to_select);
343	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, skipback);
344	TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ext_dev);
345}
346
347static void trackpoint_disconnect(struct psmouse *psmouse)
348{
349	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj, &trackpoint_attr_group);
350
351	kfree(psmouse->private);
352	psmouse->private = NULL;
353}
354
355static int trackpoint_reconnect(struct psmouse *psmouse)
356{
357	int reset_fail;
358
359	if (trackpoint_start_protocol(psmouse, NULL))
360		return -1;
361
362	reset_fail = trackpoint_power_on_reset(&psmouse->ps2dev);
363	if (trackpoint_sync(psmouse, !reset_fail))
364		return -1;
365
366	return 0;
367}
368
369int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
370{
371	struct ps2dev *ps2dev = &psmouse->ps2dev;
372	unsigned char firmware_id;
373	unsigned char button_info;
374	int error;
375
376	if (trackpoint_start_protocol(psmouse, &firmware_id))
377		return -1;
378
379	if (!set_properties)
380		return 0;
381
382	if (trackpoint_read(&psmouse->ps2dev, TP_EXT_BTN, &button_info)) {
383		psmouse_warn(psmouse, "failed to get extended button data\n");
384		button_info = 0;
385	}
386
387	psmouse->private = kzalloc(sizeof(struct trackpoint_data), GFP_KERNEL);
388	if (!psmouse->private)
389		return -ENOMEM;
390
391	psmouse->vendor = "IBM";
392	psmouse->name = "TrackPoint";
393
394	psmouse->reconnect = trackpoint_reconnect;
395	psmouse->disconnect = trackpoint_disconnect;
396
397	if ((button_info & 0x0f) >= 3)
398		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
399
400	__set_bit(INPUT_PROP_POINTER, psmouse->dev->propbit);
401	__set_bit(INPUT_PROP_POINTING_STICK, psmouse->dev->propbit);
402
403	trackpoint_defaults(psmouse->private);
404
405	error = trackpoint_power_on_reset(&psmouse->ps2dev);
406
407	/* Write defaults to TP only if reset fails. */
408	if (error)
409		trackpoint_sync(psmouse, false);
410
411	error = sysfs_create_group(&ps2dev->serio->dev.kobj, &trackpoint_attr_group);
412	if (error) {
413		psmouse_err(psmouse,
414			    "failed to create sysfs attributes, error: %d\n",
415			    error);
416		kfree(psmouse->private);
417		psmouse->private = NULL;
418		return -1;
419	}
420
421	psmouse_info(psmouse,
422		     "IBM TrackPoint firmware: 0x%02x, buttons: %d/%d\n",
423		     firmware_id,
424		     (button_info & 0xf0) >> 4, button_info & 0x0f);
425
426	return 0;
427}
428
429