1 /*
2  * HID Sensors Driver
3  * Copyright (c) 2012, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  */
19 #include <linux/device.h>
20 #include <linux/platform_device.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/slab.h>
25 #include <linux/hid-sensor-hub.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 
29 static struct {
30 	u32 usage_id;
31 	int unit; /* 0 for default others from HID sensor spec */
32 	int scale_val0; /* scale, whole number */
33 	int scale_val1; /* scale, fraction in nanos */
34 } unit_conversion[] = {
35 	{HID_USAGE_SENSOR_ACCEL_3D, 0, 9, 806650000},
36 	{HID_USAGE_SENSOR_ACCEL_3D,
37 		HID_USAGE_SENSOR_UNITS_METERS_PER_SEC_SQRD, 1, 0},
38 	{HID_USAGE_SENSOR_ACCEL_3D,
39 		HID_USAGE_SENSOR_UNITS_G, 9, 806650000},
40 
41 	{HID_USAGE_SENSOR_GRAVITY_VECTOR, 0, 9, 806650000},
42 	{HID_USAGE_SENSOR_GRAVITY_VECTOR,
43 		HID_USAGE_SENSOR_UNITS_METERS_PER_SEC_SQRD, 1, 0},
44 	{HID_USAGE_SENSOR_GRAVITY_VECTOR,
45 		HID_USAGE_SENSOR_UNITS_G, 9, 806650000},
46 
47 	{HID_USAGE_SENSOR_GYRO_3D, 0, 0, 17453293},
48 	{HID_USAGE_SENSOR_GYRO_3D,
49 		HID_USAGE_SENSOR_UNITS_RADIANS_PER_SECOND, 1, 0},
50 	{HID_USAGE_SENSOR_GYRO_3D,
51 		HID_USAGE_SENSOR_UNITS_DEGREES_PER_SECOND, 0, 17453293},
52 
53 	{HID_USAGE_SENSOR_COMPASS_3D, 0, 0, 1000000},
54 	{HID_USAGE_SENSOR_COMPASS_3D, HID_USAGE_SENSOR_UNITS_GAUSS, 1, 0},
55 
56 	{HID_USAGE_SENSOR_INCLINOMETER_3D, 0, 0, 17453293},
57 	{HID_USAGE_SENSOR_INCLINOMETER_3D,
58 		HID_USAGE_SENSOR_UNITS_DEGREES, 0, 17453293},
59 	{HID_USAGE_SENSOR_INCLINOMETER_3D,
60 		HID_USAGE_SENSOR_UNITS_RADIANS, 1, 0},
61 
62 	{HID_USAGE_SENSOR_ALS, 0, 1, 0},
63 	{HID_USAGE_SENSOR_ALS, HID_USAGE_SENSOR_UNITS_LUX, 1, 0},
64 
65 	{HID_USAGE_SENSOR_PRESSURE, 0, 100, 0},
66 	{HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 0, 1000000},
67 
68 	{HID_USAGE_SENSOR_TIME_TIMESTAMP, 0, 1000000000, 0},
69 	{HID_USAGE_SENSOR_TIME_TIMESTAMP, HID_USAGE_SENSOR_UNITS_MILLISECOND,
70 		1000000, 0},
71 
72 	{HID_USAGE_SENSOR_DEVICE_ORIENTATION, 0, 1, 0},
73 
74 	{HID_USAGE_SENSOR_RELATIVE_ORIENTATION, 0, 1, 0},
75 
76 	{HID_USAGE_SENSOR_GEOMAGNETIC_ORIENTATION, 0, 1, 0},
77 
78 	{HID_USAGE_SENSOR_TEMPERATURE, 0, 1000, 0},
79 	{HID_USAGE_SENSOR_TEMPERATURE, HID_USAGE_SENSOR_UNITS_DEGREES, 1000, 0},
80 
81 	{HID_USAGE_SENSOR_HUMIDITY, 0, 1000, 0},
82 };
83 
84 static int pow_10(unsigned power)
85 {
86 	int i;
87 	int ret = 1;
88 	for (i = 0; i < power; ++i)
89 		ret = ret * 10;
90 
91 	return ret;
92 }
93 
94 static void simple_div(int dividend, int divisor, int *whole,
95 				int *micro_frac)
96 {
97 	int rem;
98 	int exp = 0;
99 
100 	*micro_frac = 0;
101 	if (divisor == 0) {
102 		*whole = 0;
103 		return;
104 	}
105 	*whole = dividend/divisor;
106 	rem = dividend % divisor;
107 	if (rem) {
108 		while (rem <= divisor) {
109 			rem *= 10;
110 			exp++;
111 		}
112 		*micro_frac = (rem / divisor) * pow_10(6-exp);
113 	}
114 }
115 
116 static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
117 {
118 	*val1 = no/pow_10(exp);
119 	*val2 = no%pow_10(exp) * pow_10(6-exp);
120 }
121 
122 /*
123 VTF format uses exponent and variable size format.
124 For example if the size is 2 bytes
125 0x0067 with VTF16E14 format -> +1.03
126 To convert just change to 0x67 to decimal and use two decimal as E14 stands
127 for 10^-2.
128 Negative numbers are 2's complement
129 */
130 static void convert_from_vtf_format(u32 value, int size, int exp,
131 					int *val1, int *val2)
132 {
133 	int sign = 1;
134 
135 	if (value & BIT(size*8 - 1)) {
136 		value =  ((1LL << (size * 8)) - value);
137 		sign = -1;
138 	}
139 	exp = hid_sensor_convert_exponent(exp);
140 	if (exp >= 0) {
141 		*val1 = sign * value * pow_10(exp);
142 		*val2 = 0;
143 	} else {
144 		split_micro_fraction(value, -exp, val1, val2);
145 		if (*val1)
146 			*val1 = sign * (*val1);
147 		else
148 			*val2 = sign * (*val2);
149 	}
150 }
151 
152 static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
153 {
154 	u32 value;
155 	int sign = 1;
156 
157 	if (val1 < 0 || val2 < 0)
158 		sign = -1;
159 	exp = hid_sensor_convert_exponent(exp);
160 	if (exp < 0) {
161 		value = abs(val1) * pow_10(-exp);
162 		value += abs(val2) / pow_10(6+exp);
163 	} else
164 		value = abs(val1) / pow_10(exp);
165 	if (sign < 0)
166 		value =  ((1LL << (size * 8)) - value);
167 
168 	return value;
169 }
170 
171 s32 hid_sensor_read_poll_value(struct hid_sensor_common *st)
172 {
173 	s32 value = 0;
174 	int ret;
175 
176 	ret = sensor_hub_get_feature(st->hsdev,
177 				     st->poll.report_id,
178 				     st->poll.index, sizeof(value), &value);
179 
180 	if (ret < 0 || value < 0) {
181 		return -EINVAL;
182 	} else {
183 		if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
184 			value = value * 1000;
185 	}
186 
187 	return value;
188 }
189 EXPORT_SYMBOL(hid_sensor_read_poll_value);
190 
191 int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,
192 				int *val1, int *val2)
193 {
194 	s32 value;
195 	int ret;
196 
197 	ret = sensor_hub_get_feature(st->hsdev,
198 				     st->poll.report_id,
199 				     st->poll.index, sizeof(value), &value);
200 	if (ret < 0 || value < 0) {
201 		*val1 = *val2 = 0;
202 		return -EINVAL;
203 	} else {
204 		if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
205 			simple_div(1000, value, val1, val2);
206 		else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
207 			simple_div(1, value, val1, val2);
208 		else {
209 			*val1 = *val2 = 0;
210 			return -EINVAL;
211 		}
212 	}
213 
214 	return IIO_VAL_INT_PLUS_MICRO;
215 }
216 EXPORT_SYMBOL(hid_sensor_read_samp_freq_value);
217 
218 int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
219 				int val1, int val2)
220 {
221 	s32 value;
222 	int ret;
223 
224 	if (val1 < 0 || val2 < 0)
225 		return -EINVAL;
226 
227 	value = val1 * pow_10(6) + val2;
228 	if (value) {
229 		if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
230 			value = pow_10(9)/value;
231 		else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
232 			value = pow_10(6)/value;
233 		else
234 			value = 0;
235 	}
236 	ret = sensor_hub_set_feature(st->hsdev, st->poll.report_id,
237 				     st->poll.index, sizeof(value), &value);
238 	if (ret < 0 || value < 0)
239 		return -EINVAL;
240 
241 	ret = sensor_hub_get_feature(st->hsdev,
242 				     st->poll.report_id,
243 				     st->poll.index, sizeof(value), &value);
244 	if (ret < 0 || value < 0)
245 		return -EINVAL;
246 
247 	st->poll_interval = value;
248 
249 	return 0;
250 }
251 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);
252 
253 int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
254 				int *val1, int *val2)
255 {
256 	s32 value;
257 	int ret;
258 
259 	ret = sensor_hub_get_feature(st->hsdev,
260 				     st->sensitivity.report_id,
261 				     st->sensitivity.index, sizeof(value),
262 				     &value);
263 	if (ret < 0 || value < 0) {
264 		*val1 = *val2 = 0;
265 		return -EINVAL;
266 	} else {
267 		convert_from_vtf_format(value, st->sensitivity.size,
268 					st->sensitivity.unit_expo,
269 					val1, val2);
270 	}
271 
272 	return IIO_VAL_INT_PLUS_MICRO;
273 }
274 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);
275 
276 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
277 					int val1, int val2)
278 {
279 	s32 value;
280 	int ret;
281 
282 	if (val1 < 0 || val2 < 0)
283 		return -EINVAL;
284 
285 	value = convert_to_vtf_format(st->sensitivity.size,
286 				st->sensitivity.unit_expo,
287 				val1, val2);
288 	ret = sensor_hub_set_feature(st->hsdev, st->sensitivity.report_id,
289 				     st->sensitivity.index, sizeof(value),
290 				     &value);
291 	if (ret < 0 || value < 0)
292 		return -EINVAL;
293 
294 	ret = sensor_hub_get_feature(st->hsdev,
295 				     st->sensitivity.report_id,
296 				     st->sensitivity.index, sizeof(value),
297 				     &value);
298 	if (ret < 0 || value < 0)
299 		return -EINVAL;
300 
301 	st->raw_hystersis = value;
302 
303 	return 0;
304 }
305 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
306 
307 /*
308  * This fuction applies the unit exponent to the scale.
309  * For example:
310  * 9.806650000 ->exp:2-> val0[980]val1[665000000]
311  * 9.000806000 ->exp:2-> val0[900]val1[80600000]
312  * 0.174535293 ->exp:2-> val0[17]val1[453529300]
313  * 1.001745329 ->exp:0-> val0[1]val1[1745329]
314  * 1.001745329 ->exp:2-> val0[100]val1[174532900]
315  * 1.001745329 ->exp:4-> val0[10017]val1[453290000]
316  * 9.806650000 ->exp:-2-> val0[0]val1[98066500]
317  */
318 static void adjust_exponent_nano(int *val0, int *val1, int scale0,
319 				  int scale1, int exp)
320 {
321 	int i;
322 	int x;
323 	int res;
324 	int rem;
325 
326 	if (exp > 0) {
327 		*val0 = scale0 * pow_10(exp);
328 		res = 0;
329 		if (exp > 9) {
330 			*val1 = 0;
331 			return;
332 		}
333 		for (i = 0; i < exp; ++i) {
334 			x = scale1 / pow_10(8 - i);
335 			res += (pow_10(exp - 1 - i) * x);
336 			scale1 = scale1 % pow_10(8 - i);
337 		}
338 		*val0 += res;
339 		*val1 = scale1 * pow_10(exp);
340 	} else if (exp < 0) {
341 		exp = abs(exp);
342 		if (exp > 9) {
343 			*val0 = *val1 = 0;
344 			return;
345 		}
346 		*val0 = scale0 / pow_10(exp);
347 		rem = scale0 % pow_10(exp);
348 		res = 0;
349 		for (i = 0; i < (9 - exp); ++i) {
350 			x = scale1 / pow_10(8 - i);
351 			res += (pow_10(8 - exp - i) * x);
352 			scale1 = scale1 % pow_10(8 - i);
353 		}
354 		*val1 = rem * pow_10(9 - exp) + res;
355 	} else {
356 		*val0 = scale0;
357 		*val1 = scale1;
358 	}
359 }
360 
361 int hid_sensor_format_scale(u32 usage_id,
362 			struct hid_sensor_hub_attribute_info *attr_info,
363 			int *val0, int *val1)
364 {
365 	int i;
366 	int exp;
367 
368 	*val0 = 1;
369 	*val1 = 0;
370 
371 	for (i = 0; i < ARRAY_SIZE(unit_conversion); ++i) {
372 		if (unit_conversion[i].usage_id == usage_id &&
373 			unit_conversion[i].unit == attr_info->units) {
374 			exp  = hid_sensor_convert_exponent(
375 						attr_info->unit_expo);
376 			adjust_exponent_nano(val0, val1,
377 					unit_conversion[i].scale_val0,
378 					unit_conversion[i].scale_val1, exp);
379 			break;
380 		}
381 	}
382 
383 	return IIO_VAL_INT_PLUS_NANO;
384 }
385 EXPORT_SYMBOL(hid_sensor_format_scale);
386 
387 int64_t hid_sensor_convert_timestamp(struct hid_sensor_common *st,
388 				     int64_t raw_value)
389 {
390 	return st->timestamp_ns_scale * raw_value;
391 }
392 EXPORT_SYMBOL(hid_sensor_convert_timestamp);
393 
394 static
395 int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
396 					u32 usage_id,
397 					struct hid_sensor_common *st)
398 {
399 	sensor_hub_input_get_attribute_info(hsdev,
400 					HID_FEATURE_REPORT, usage_id,
401 					HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
402 					&st->poll);
403 	/* Default unit of measure is milliseconds */
404 	if (st->poll.units == 0)
405 		st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
406 
407 	st->poll_interval = -1;
408 
409 	return 0;
410 
411 }
412 
413 static void hid_sensor_get_report_latency_info(struct hid_sensor_hub_device *hsdev,
414 					       u32 usage_id,
415 					       struct hid_sensor_common *st)
416 {
417 	sensor_hub_input_get_attribute_info(hsdev, HID_FEATURE_REPORT,
418 					    usage_id,
419 					    HID_USAGE_SENSOR_PROP_REPORT_LATENCY,
420 					    &st->report_latency);
421 
422 	hid_dbg(hsdev->hdev, "Report latency attributes: %x:%x\n",
423 		st->report_latency.index, st->report_latency.report_id);
424 }
425 
426 int hid_sensor_get_report_latency(struct hid_sensor_common *st)
427 {
428 	int ret;
429 	int value;
430 
431 	ret = sensor_hub_get_feature(st->hsdev, st->report_latency.report_id,
432 				     st->report_latency.index, sizeof(value),
433 				     &value);
434 	if (ret < 0)
435 		return ret;
436 
437 	return value;
438 }
439 EXPORT_SYMBOL(hid_sensor_get_report_latency);
440 
441 int hid_sensor_set_report_latency(struct hid_sensor_common *st, int latency_ms)
442 {
443 	return sensor_hub_set_feature(st->hsdev, st->report_latency.report_id,
444 				      st->report_latency.index,
445 				      sizeof(latency_ms), &latency_ms);
446 }
447 EXPORT_SYMBOL(hid_sensor_set_report_latency);
448 
449 bool hid_sensor_batch_mode_supported(struct hid_sensor_common *st)
450 {
451 	return st->report_latency.index > 0 && st->report_latency.report_id > 0;
452 }
453 EXPORT_SYMBOL(hid_sensor_batch_mode_supported);
454 
455 int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
456 					u32 usage_id,
457 					struct hid_sensor_common *st)
458 {
459 
460 	struct hid_sensor_hub_attribute_info timestamp;
461 	s32 value;
462 	int ret;
463 
464 	hid_sensor_get_reporting_interval(hsdev, usage_id, st);
465 
466 	sensor_hub_input_get_attribute_info(hsdev,
467 					HID_FEATURE_REPORT, usage_id,
468 					HID_USAGE_SENSOR_PROP_REPORT_STATE,
469 					&st->report_state);
470 
471 	sensor_hub_input_get_attribute_info(hsdev,
472 					HID_FEATURE_REPORT, usage_id,
473 					HID_USAGE_SENSOR_PROY_POWER_STATE,
474 					&st->power_state);
475 
476 	st->power_state.logical_minimum = 1;
477 	st->report_state.logical_minimum = 1;
478 
479 	sensor_hub_input_get_attribute_info(hsdev,
480 			HID_FEATURE_REPORT, usage_id,
481 			HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
482 			 &st->sensitivity);
483 
484 	st->raw_hystersis = -1;
485 
486 	sensor_hub_input_get_attribute_info(hsdev,
487 					    HID_INPUT_REPORT, usage_id,
488 					    HID_USAGE_SENSOR_TIME_TIMESTAMP,
489 					    &timestamp);
490 	if (timestamp.index >= 0 && timestamp.report_id) {
491 		int val0, val1;
492 
493 		hid_sensor_format_scale(HID_USAGE_SENSOR_TIME_TIMESTAMP,
494 					&timestamp, &val0, &val1);
495 		st->timestamp_ns_scale = val0;
496 	} else
497 		st->timestamp_ns_scale = 1000000000;
498 
499 	hid_sensor_get_report_latency_info(hsdev, usage_id, st);
500 
501 	hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x %x:%x\n",
502 		st->poll.index, st->poll.report_id,
503 		st->report_state.index, st->report_state.report_id,
504 		st->power_state.index, st->power_state.report_id,
505 		st->sensitivity.index, st->sensitivity.report_id,
506 		timestamp.index, timestamp.report_id);
507 
508 	ret = sensor_hub_get_feature(hsdev,
509 				st->power_state.report_id,
510 				st->power_state.index, sizeof(value), &value);
511 	if (ret < 0)
512 		return ret;
513 	if (value < 0)
514 		return -EINVAL;
515 
516 	return 0;
517 }
518 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);
519 
520 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
521 MODULE_DESCRIPTION("HID Sensor common attribute processing");
522 MODULE_LICENSE("GPL");
523