Pileus Git - ~andy/linux/blob - drivers/iio/common/hid-sensors/hid-sensor-attributes.c

   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 #include "hid-sensor-attributes.h"
  29
  30 static int pow_10(unsigned power)
  31 {
  32         int i;
  33         int ret = 1;
  34         for (i = 0; i < power; ++i)
  35                 ret = ret * 10;
  36
  37         return ret;
  38 }
  39
  40 static void simple_div(int dividend, int divisor, int *whole,
  41                                 int *micro_frac)
  42 {
  43         int rem;
  44         int exp = 0;
  45
  46         *micro_frac = 0;
  47         if (divisor == 0) {
  48                 *whole = 0;
  49                 return;
  50         }
  51         *whole = dividend/divisor;
  52         rem = dividend % divisor;
  53         if (rem) {
  54                 while (rem <= divisor) {
  55                         rem *= 10;
  56                         exp++;
  57                 }
  58                 *micro_frac = (rem / divisor) * pow_10(6-exp);
  59         }
  60 }
  61
  62 static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
  63 {
  64         *val1 = no/pow_10(exp);
  65         *val2 = no%pow_10(exp) * pow_10(6-exp);
  66 }
  67
  68 /*
  69 VTF format uses exponent and variable size format.
  70 For example if the size is 2 bytes
  71 0x0067 with VTF16E14 format -> +1.03
  72 To convert just change to 0x67 to decimal and use two decimal as E14 stands
  73 for 10^-2.
  74 Negative numbers are 2's complement
  75 */
  76 static void convert_from_vtf_format(u32 value, int size, int exp,
  77                                         int *val1, int *val2)
  78 {
  79         int sign = 1;
  80
  81         if (value & BIT(size*8 - 1)) {
  82                 value =  ((1LL << (size * 8)) - value);
  83                 sign = -1;
  84         }
  85         exp = hid_sensor_convert_exponent(exp);
  86         if (exp >= 0) {
  87                 *val1 = sign * value * pow_10(exp);
  88                 *val2 = 0;
  89         } else {
  90                 split_micro_fraction(value, -exp, val1, val2);
  91                 if (*val1)
  92                         *val1 = sign * (*val1);
  93                 else
  94                         *val2 = sign * (*val2);
  95         }
  96 }
  97
  98 static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
  99 {
 100         u32 value;
 101         int sign = 1;
 102
 103         if (val1 < 0 || val2 < 0)
 104                 sign = -1;
 105         exp = hid_sensor_convert_exponent(exp);
 106         if (exp < 0) {
 107                 value = abs(val1) * pow_10(-exp);
 108                 value += abs(val2) / pow_10(6+exp);
 109         } else
 110                 value = abs(val1) / pow_10(exp);
 111         if (sign < 0)
 112                 value =  ((1LL << (size * 8)) - value);
 113
 114         return value;
 115 }
 116
 117 int hid_sensor_read_samp_freq_value(struct hid_sensor_iio_common *st,
 118                                 int *val1, int *val2)
 119 {
 120         s32 value;
 121         int ret;
 122
 123         ret = sensor_hub_get_feature(st->hsdev,
 124                 st->poll.report_id,
 125                 st->poll.index, &value);
 126         if (ret < 0 || value < 0) {
 127                 *val1 = *val2 = 0;
 128                 return -EINVAL;
 129         } else {
 130                 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
 131                         simple_div(1000, value, val1, val2);
 132                 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
 133                         simple_div(1, value, val1, val2);
 134                 else {
 135                         *val1 = *val2 = 0;
 136                         return -EINVAL;
 137                 }
 138         }
 139
 140         return IIO_VAL_INT_PLUS_MICRO;
 141 }
 142 EXPORT_SYMBOL(hid_sensor_read_samp_freq_value);
 143
 144 int hid_sensor_write_samp_freq_value(struct hid_sensor_iio_common *st,
 145                                 int val1, int val2)
 146 {
 147         s32 value;
 148         int ret;
 149
 150         if (val1 < 0 || val2 < 0)
 151                 ret = -EINVAL;
 152
 153         value = val1 * pow_10(6) + val2;
 154         if (value) {
 155                 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
 156                         value = pow_10(9)/value;
 157                 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
 158                         value = pow_10(6)/value;
 159                 else
 160                         value = 0;
 161         }
 162         ret = sensor_hub_set_feature(st->hsdev,
 163                 st->poll.report_id,
 164                 st->poll.index, value);
 165         if (ret < 0 || value < 0)
 166                 ret = -EINVAL;
 167
 168         return ret;
 169 }
 170 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);
 171
 172 int hid_sensor_read_raw_hyst_value(struct hid_sensor_iio_common *st,
 173                                 int *val1, int *val2)
 174 {
 175         s32 value;
 176         int ret;
 177
 178         ret = sensor_hub_get_feature(st->hsdev,
 179                 st->sensitivity.report_id,
 180                 st->sensitivity.index, &value);
 181         if (ret < 0 || value < 0) {
 182                 *val1 = *val2 = 0;
 183                 return -EINVAL;
 184         } else {
 185                 convert_from_vtf_format(value, st->sensitivity.size,
 186                                         st->sensitivity.unit_expo,
 187                                         val1, val2);
 188         }
 189
 190         return IIO_VAL_INT_PLUS_MICRO;
 191 }
 192 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);
 193
 194 int hid_sensor_write_raw_hyst_value(struct hid_sensor_iio_common *st,
 195                                         int val1, int val2)
 196 {
 197         s32 value;
 198         int ret;
 199
 200         value = convert_to_vtf_format(st->sensitivity.size,
 201                                 st->sensitivity.unit_expo,
 202                                 val1, val2);
 203         ret = sensor_hub_set_feature(st->hsdev,
 204                 st->sensitivity.report_id,
 205                 st->sensitivity.index, value);
 206         if (ret < 0 || value < 0)
 207                 ret = -EINVAL;
 208
 209         return ret;
 210 }
 211 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
 212
 213 int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 214                                         u32 usage_id,
 215                                         struct hid_sensor_iio_common *st)
 216 {
 217
 218         sensor_hub_input_get_attribute_info(hsdev,
 219                                         HID_FEATURE_REPORT, usage_id,
 220                                         HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
 221                                         &st->poll);
 222
 223         sensor_hub_input_get_attribute_info(hsdev,
 224                                         HID_FEATURE_REPORT, usage_id,
 225                                         HID_USAGE_SENSOR_PROP_REPORT_STATE,
 226                                         &st->report_state);
 227
 228         sensor_hub_input_get_attribute_info(hsdev,
 229                                         HID_FEATURE_REPORT, usage_id,
 230                                         HID_USAGE_SENSOR_PROY_POWER_STATE,
 231                                         &st->power_state);
 232
 233         sensor_hub_input_get_attribute_info(hsdev,
 234                         HID_FEATURE_REPORT, usage_id,
 235                         HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
 236                          &st->sensitivity);
 237
 238         hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x\n",
 239                         st->poll.index, st->poll.report_id,
 240                         st->report_state.index, st->report_state.report_id,
 241                         st->power_state.index, st->power_state.report_id,
 242                         st->sensitivity.index, st->sensitivity.report_id);
 243
 244         return 0;
 245 }
 246 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);
 247
 248 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 249 MODULE_DESCRIPTION("HID Sensor common attribute processing");
 250 MODULE_LICENSE("GPL");