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_GYRO_3D, 0, 0, 17453293},
42 {HID_USAGE_SENSOR_GYRO_3D,
43 HID_USAGE_SENSOR_UNITS_RADIANS_PER_SECOND, 1, 0},
44 {HID_USAGE_SENSOR_GYRO_3D,
45 HID_USAGE_SENSOR_UNITS_DEGREES_PER_SECOND, 0, 17453293},
46
47 {HID_USAGE_SENSOR_COMPASS_3D, 0, 0, 1000000},
48 {HID_USAGE_SENSOR_COMPASS_3D, HID_USAGE_SENSOR_UNITS_GAUSS, 1, 0},
49
50 {HID_USAGE_SENSOR_INCLINOMETER_3D, 0, 0, 17453293},
51 {HID_USAGE_SENSOR_INCLINOMETER_3D,
52 HID_USAGE_SENSOR_UNITS_DEGREES, 0, 17453293},
53 {HID_USAGE_SENSOR_INCLINOMETER_3D,
54 HID_USAGE_SENSOR_UNITS_RADIANS, 1, 0},
55
56 {HID_USAGE_SENSOR_ALS, 0, 1, 0},
57 {HID_USAGE_SENSOR_ALS, HID_USAGE_SENSOR_UNITS_LUX, 1, 0},
58
59 {HID_USAGE_SENSOR_PRESSURE, 0, 100, 0},
60 {HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 0, 1000000},
61 };
62
pow_10(unsigned power)63 static int pow_10(unsigned power)
64 {
65 int i;
66 int ret = 1;
67 for (i = 0; i < power; ++i)
68 ret = ret * 10;
69
70 return ret;
71 }
72
simple_div(int dividend,int divisor,int * whole,int * micro_frac)73 static void simple_div(int dividend, int divisor, int *whole,
74 int *micro_frac)
75 {
76 int rem;
77 int exp = 0;
78
79 *micro_frac = 0;
80 if (divisor == 0) {
81 *whole = 0;
82 return;
83 }
84 *whole = dividend/divisor;
85 rem = dividend % divisor;
86 if (rem) {
87 while (rem <= divisor) {
88 rem *= 10;
89 exp++;
90 }
91 *micro_frac = (rem / divisor) * pow_10(6-exp);
92 }
93 }
94
split_micro_fraction(unsigned int no,int exp,int * val1,int * val2)95 static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
96 {
97 *val1 = no/pow_10(exp);
98 *val2 = no%pow_10(exp) * pow_10(6-exp);
99 }
100
101 /*
102 VTF format uses exponent and variable size format.
103 For example if the size is 2 bytes
104 0x0067 with VTF16E14 format -> +1.03
105 To convert just change to 0x67 to decimal and use two decimal as E14 stands
106 for 10^-2.
107 Negative numbers are 2's complement
108 */
convert_from_vtf_format(u32 value,int size,int exp,int * val1,int * val2)109 static void convert_from_vtf_format(u32 value, int size, int exp,
110 int *val1, int *val2)
111 {
112 int sign = 1;
113
114 if (value & BIT(size*8 - 1)) {
115 value = ((1LL << (size * 8)) - value);
116 sign = -1;
117 }
118 exp = hid_sensor_convert_exponent(exp);
119 if (exp >= 0) {
120 *val1 = sign * value * pow_10(exp);
121 *val2 = 0;
122 } else {
123 split_micro_fraction(value, -exp, val1, val2);
124 if (*val1)
125 *val1 = sign * (*val1);
126 else
127 *val2 = sign * (*val2);
128 }
129 }
130
convert_to_vtf_format(int size,int exp,int val1,int val2)131 static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
132 {
133 u32 value;
134 int sign = 1;
135
136 if (val1 < 0 || val2 < 0)
137 sign = -1;
138 exp = hid_sensor_convert_exponent(exp);
139 if (exp < 0) {
140 value = abs(val1) * pow_10(-exp);
141 value += abs(val2) / pow_10(6+exp);
142 } else
143 value = abs(val1) / pow_10(exp);
144 if (sign < 0)
145 value = ((1LL << (size * 8)) - value);
146
147 return value;
148 }
149
hid_sensor_read_poll_value(struct hid_sensor_common * st)150 s32 hid_sensor_read_poll_value(struct hid_sensor_common *st)
151 {
152 s32 value = 0;
153 int ret;
154
155 ret = sensor_hub_get_feature(st->hsdev,
156 st->poll.report_id,
157 st->poll.index, sizeof(value), &value);
158
159 if (ret < 0 || value < 0) {
160 return -EINVAL;
161 } else {
162 if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
163 value = value * 1000;
164 }
165
166 return value;
167 }
168 EXPORT_SYMBOL(hid_sensor_read_poll_value);
169
hid_sensor_read_samp_freq_value(struct hid_sensor_common * st,int * val1,int * val2)170 int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,
171 int *val1, int *val2)
172 {
173 s32 value;
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 if (ret < 0 || value < 0) {
180 *val1 = *val2 = 0;
181 return -EINVAL;
182 } else {
183 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
184 simple_div(1000, value, val1, val2);
185 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
186 simple_div(1, value, val1, val2);
187 else {
188 *val1 = *val2 = 0;
189 return -EINVAL;
190 }
191 }
192
193 return IIO_VAL_INT_PLUS_MICRO;
194 }
195 EXPORT_SYMBOL(hid_sensor_read_samp_freq_value);
196
hid_sensor_write_samp_freq_value(struct hid_sensor_common * st,int val1,int val2)197 int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
198 int val1, int val2)
199 {
200 s32 value;
201 int ret;
202
203 if (val1 < 0 || val2 < 0)
204 ret = -EINVAL;
205
206 value = val1 * pow_10(6) + val2;
207 if (value) {
208 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
209 value = pow_10(9)/value;
210 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
211 value = pow_10(6)/value;
212 else
213 value = 0;
214 }
215 ret = sensor_hub_set_feature(st->hsdev, st->poll.report_id,
216 st->poll.index, sizeof(value), &value);
217 if (ret < 0 || value < 0)
218 ret = -EINVAL;
219
220 return ret;
221 }
222 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);
223
hid_sensor_read_raw_hyst_value(struct hid_sensor_common * st,int * val1,int * val2)224 int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
225 int *val1, int *val2)
226 {
227 s32 value;
228 int ret;
229
230 ret = sensor_hub_get_feature(st->hsdev,
231 st->sensitivity.report_id,
232 st->sensitivity.index, sizeof(value),
233 &value);
234 if (ret < 0 || value < 0) {
235 *val1 = *val2 = 0;
236 return -EINVAL;
237 } else {
238 convert_from_vtf_format(value, st->sensitivity.size,
239 st->sensitivity.unit_expo,
240 val1, val2);
241 }
242
243 return IIO_VAL_INT_PLUS_MICRO;
244 }
245 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);
246
hid_sensor_write_raw_hyst_value(struct hid_sensor_common * st,int val1,int val2)247 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
248 int val1, int val2)
249 {
250 s32 value;
251 int ret;
252
253 value = convert_to_vtf_format(st->sensitivity.size,
254 st->sensitivity.unit_expo,
255 val1, val2);
256 ret = sensor_hub_set_feature(st->hsdev, st->sensitivity.report_id,
257 st->sensitivity.index, sizeof(value),
258 &value);
259 if (ret < 0 || value < 0)
260 ret = -EINVAL;
261
262 return ret;
263 }
264 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
265
266 /*
267 * This fuction applies the unit exponent to the scale.
268 * For example:
269 * 9.806650000 ->exp:2-> val0[980]val1[665000000]
270 * 9.000806000 ->exp:2-> val0[900]val1[80600000]
271 * 0.174535293 ->exp:2-> val0[17]val1[453529300]
272 * 1.001745329 ->exp:0-> val0[1]val1[1745329]
273 * 1.001745329 ->exp:2-> val0[100]val1[174532900]
274 * 1.001745329 ->exp:4-> val0[10017]val1[453290000]
275 * 9.806650000 ->exp:-2-> val0[0]val1[98066500]
276 */
adjust_exponent_nano(int * val0,int * val1,int scale0,int scale1,int exp)277 static void adjust_exponent_nano(int *val0, int *val1, int scale0,
278 int scale1, int exp)
279 {
280 int i;
281 int x;
282 int res;
283 int rem;
284
285 if (exp > 0) {
286 *val0 = scale0 * pow_10(exp);
287 res = 0;
288 if (exp > 9) {
289 *val1 = 0;
290 return;
291 }
292 for (i = 0; i < exp; ++i) {
293 x = scale1 / pow_10(8 - i);
294 res += (pow_10(exp - 1 - i) * x);
295 scale1 = scale1 % pow_10(8 - i);
296 }
297 *val0 += res;
298 *val1 = scale1 * pow_10(exp);
299 } else if (exp < 0) {
300 exp = abs(exp);
301 if (exp > 9) {
302 *val0 = *val1 = 0;
303 return;
304 }
305 *val0 = scale0 / pow_10(exp);
306 rem = scale0 % pow_10(exp);
307 res = 0;
308 for (i = 0; i < (9 - exp); ++i) {
309 x = scale1 / pow_10(8 - i);
310 res += (pow_10(8 - exp - i) * x);
311 scale1 = scale1 % pow_10(8 - i);
312 }
313 *val1 = rem * pow_10(9 - exp) + res;
314 } else {
315 *val0 = scale0;
316 *val1 = scale1;
317 }
318 }
319
hid_sensor_format_scale(u32 usage_id,struct hid_sensor_hub_attribute_info * attr_info,int * val0,int * val1)320 int hid_sensor_format_scale(u32 usage_id,
321 struct hid_sensor_hub_attribute_info *attr_info,
322 int *val0, int *val1)
323 {
324 int i;
325 int exp;
326
327 *val0 = 1;
328 *val1 = 0;
329
330 for (i = 0; i < ARRAY_SIZE(unit_conversion); ++i) {
331 if (unit_conversion[i].usage_id == usage_id &&
332 unit_conversion[i].unit == attr_info->units) {
333 exp = hid_sensor_convert_exponent(
334 attr_info->unit_expo);
335 adjust_exponent_nano(val0, val1,
336 unit_conversion[i].scale_val0,
337 unit_conversion[i].scale_val1, exp);
338 break;
339 }
340 }
341
342 return IIO_VAL_INT_PLUS_NANO;
343 }
344 EXPORT_SYMBOL(hid_sensor_format_scale);
345
346 static
hid_sensor_get_reporting_interval(struct hid_sensor_hub_device * hsdev,u32 usage_id,struct hid_sensor_common * st)347 int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
348 u32 usage_id,
349 struct hid_sensor_common *st)
350 {
351 sensor_hub_input_get_attribute_info(hsdev,
352 HID_FEATURE_REPORT, usage_id,
353 HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
354 &st->poll);
355 /* Default unit of measure is milliseconds */
356 if (st->poll.units == 0)
357 st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
358 return 0;
359
360 }
361
hid_sensor_parse_common_attributes(struct hid_sensor_hub_device * hsdev,u32 usage_id,struct hid_sensor_common * st)362 int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
363 u32 usage_id,
364 struct hid_sensor_common *st)
365 {
366
367
368 hid_sensor_get_reporting_interval(hsdev, usage_id, st);
369
370 sensor_hub_input_get_attribute_info(hsdev,
371 HID_FEATURE_REPORT, usage_id,
372 HID_USAGE_SENSOR_PROP_REPORT_STATE,
373 &st->report_state);
374
375 sensor_hub_input_get_attribute_info(hsdev,
376 HID_FEATURE_REPORT, usage_id,
377 HID_USAGE_SENSOR_PROY_POWER_STATE,
378 &st->power_state);
379
380 sensor_hub_input_get_attribute_info(hsdev,
381 HID_FEATURE_REPORT, usage_id,
382 HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
383 &st->sensitivity);
384
385 hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x\n",
386 st->poll.index, st->poll.report_id,
387 st->report_state.index, st->report_state.report_id,
388 st->power_state.index, st->power_state.report_id,
389 st->sensitivity.index, st->sensitivity.report_id);
390
391 return 0;
392 }
393 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);
394
395 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
396 MODULE_DESCRIPTION("HID Sensor common attribute processing");
397 MODULE_LICENSE("GPL");
398