drivers/iio/pressure/hid-sensor-press.c

   1 /*
   2  * HID Sensors Driver
   3  * Copyright (c) 2014, 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.
  16  *
  17  */
  18 #include <linux/device.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/module.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/irq.h>
  23 #include <linux/slab.h>
  24 #include <linux/delay.h>
  25 #include <linux/hid-sensor-hub.h>
  26 #include <linux/iio/iio.h>
  27 #include <linux/iio/sysfs.h>
  28 #include <linux/iio/buffer.h>
  29 #include <linux/iio/trigger_consumer.h>
  30 #include <linux/iio/triggered_buffer.h>
  31 #include "../common/hid-sensors/hid-sensor-trigger.h"
  32
  33 #define CHANNEL_SCAN_INDEX_PRESSURE 0
  34
  35 struct press_state {
  36         struct hid_sensor_hub_callbacks callbacks;
  37         struct hid_sensor_common common_attributes;
  38         struct hid_sensor_hub_attribute_info press_attr;
  39         u32 press_data;
  40         int scale_pre_decml;
  41         int scale_post_decml;
  42         int scale_precision;
  43         int value_offset;
  44 };
  45
  46 /* Channel definitions */
  47 static const struct iio_chan_spec press_channels[] = {
  48         {
  49                 .type = IIO_PRESSURE,
  50                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  51                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  52                 BIT(IIO_CHAN_INFO_SCALE) |
  53                 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  54                 BIT(IIO_CHAN_INFO_HYSTERESIS),
  55                 .scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
  56         }
  57 };
  58
  59 /* Adjust channel real bits based on report descriptor */
  60 static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  61                                         int channel, int size)
  62 {
  63         channels[channel].scan_type.sign = 's';
  64         /* Real storage bits will change based on the report desc. */
  65         channels[channel].scan_type.realbits = size * 8;
  66         /* Maximum size of a sample to capture is u32 */
  67         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  68 }
  69
  70 /* Channel read_raw handler */
  71 static int press_read_raw(struct iio_dev *indio_dev,
  72                               struct iio_chan_spec const *chan,
  73                               int *val, int *val2,
  74                               long mask)
  75 {
  76         struct press_state *press_state = iio_priv(indio_dev);
  77         int report_id = -1;
  78         u32 address;
  79         int ret_type;
  80
  81         *val = 0;
  82         *val2 = 0;
  83         switch (mask) {
  84         case IIO_CHAN_INFO_RAW:
  85                 switch (chan->scan_index) {
  86                 case  CHANNEL_SCAN_INDEX_PRESSURE:
  87                         report_id = press_state->press_attr.report_id;
  88                         address =
  89                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
  90                         break;
  91                 default:
  92                         report_id = -1;
  93                         break;
  94                 }
  95                 if (report_id >= 0) {
  96                         hid_sensor_power_state(&press_state->common_attributes,
  97                                                 true);
  98                         *val = sensor_hub_input_attr_get_raw_value(
  99                                 press_state->common_attributes.hsdev,
 100                                 HID_USAGE_SENSOR_PRESSURE, address,
 101                                 report_id,
 102                                 SENSOR_HUB_SYNC);
 103                         hid_sensor_power_state(&press_state->common_attributes,
 104                                                 false);
 105                 } else {
 106                         *val = 0;
 107                         return -EINVAL;
 108                 }
 109                 ret_type = IIO_VAL_INT;
 110                 break;
 111         case IIO_CHAN_INFO_SCALE:
 112                 *val = press_state->scale_pre_decml;
 113                 *val2 = press_state->scale_post_decml;
 114                 ret_type = press_state->scale_precision;
 115                 break;
 116         case IIO_CHAN_INFO_OFFSET:
 117                 *val = press_state->value_offset;
 118                 ret_type = IIO_VAL_INT;
 119                 break;
 120         case IIO_CHAN_INFO_SAMP_FREQ:
 121                 ret_type = hid_sensor_read_samp_freq_value(
 122                                 &press_state->common_attributes, val, val2);
 123                 break;
 124         case IIO_CHAN_INFO_HYSTERESIS:
 125                 ret_type = hid_sensor_read_raw_hyst_value(
 126                                 &press_state->common_attributes, val, val2);
 127                 break;
 128         default:
 129                 ret_type = -EINVAL;
 130                 break;
 131         }
 132
 133         return ret_type;
 134 }
 135
 136 /* Channel write_raw handler */
 137 static int press_write_raw(struct iio_dev *indio_dev,
 138                                struct iio_chan_spec const *chan,
 139                                int val,
 140                                int val2,
 141                                long mask)
 142 {
 143         struct press_state *press_state = iio_priv(indio_dev);
 144         int ret = 0;
 145
 146         switch (mask) {
 147         case IIO_CHAN_INFO_SAMP_FREQ:
 148                 ret = hid_sensor_write_samp_freq_value(
 149                                 &press_state->common_attributes, val, val2);
 150                 break;
 151         case IIO_CHAN_INFO_HYSTERESIS:
 152                 ret = hid_sensor_write_raw_hyst_value(
 153                                 &press_state->common_attributes, val, val2);
 154                 break;
 155         default:
 156                 ret = -EINVAL;
 157         }
 158
 159         return ret;
 160 }
 161
 162 static const struct iio_info press_info = {
 163         .read_raw = &press_read_raw,
 164         .write_raw = &press_write_raw,
 165 };
 166
 167 /* Function to push data to buffer */
 168 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 169                                         int len)
 170 {
 171         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 172         iio_push_to_buffers(indio_dev, data);
 173 }
 174
 175 /* Callback handler to send event after all samples are received and captured */
 176 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 177                                 unsigned usage_id,
 178                                 void *priv)
 179 {
 180         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 181         struct press_state *press_state = iio_priv(indio_dev);
 182
 183         dev_dbg(&indio_dev->dev, "press_proc_event\n");
 184         if (atomic_read(&press_state->common_attributes.data_ready))
 185                 hid_sensor_push_data(indio_dev,
 186                                 &press_state->press_data,
 187                                 sizeof(press_state->press_data));
 188
 189         return 0;
 190 }
 191
 192 /* Capture samples in local storage */
 193 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
 194                                 unsigned usage_id,
 195                                 size_t raw_len, char *raw_data,
 196                                 void *priv)
 197 {
 198         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 199         struct press_state *press_state = iio_priv(indio_dev);
 200         int ret = -EINVAL;
 201
 202         switch (usage_id) {
 203         case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
 204                 press_state->press_data = *(u32 *)raw_data;
 205                 ret = 0;
 206                 break;
 207         default:
 208                 break;
 209         }
 210
 211         return ret;
 212 }
 213
 214 /* Parse report which is specific to an usage id*/
 215 static int press_parse_report(struct platform_device *pdev,
 216                                 struct hid_sensor_hub_device *hsdev,
 217                                 struct iio_chan_spec *channels,
 218                                 unsigned usage_id,
 219                                 struct press_state *st)
 220 {
 221         int ret;
 222
 223         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 224                         usage_id,
 225                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
 226                         &st->press_attr);
 227         if (ret < 0)
 228                 return ret;
 229         press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
 230                                         st->press_attr.size);
 231
 232         dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
 233                         st->press_attr.report_id);
 234
 235         st->scale_precision = hid_sensor_format_scale(
 236                                 HID_USAGE_SENSOR_PRESSURE,
 237                                 &st->press_attr,
 238                                 &st->scale_pre_decml, &st->scale_post_decml);
 239
 240         /* Set Sensitivity field ids, when there is no individual modifier */
 241         if (st->common_attributes.sensitivity.index < 0) {
 242                 sensor_hub_input_get_attribute_info(hsdev,
 243                         HID_FEATURE_REPORT, usage_id,
 244                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 245                         HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
 246                         &st->common_attributes.sensitivity);
 247                 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 248                         st->common_attributes.sensitivity.index,
 249                         st->common_attributes.sensitivity.report_id);
 250         }
 251         return ret;
 252 }
 253
 254 /* Function to initialize the processing for usage id */
 255 static int hid_press_probe(struct platform_device *pdev)
 256 {
 257         int ret = 0;
 258         static const char *name = "press";
 259         struct iio_dev *indio_dev;
 260         struct press_state *press_state;
 261         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 262
 263         indio_dev = devm_iio_device_alloc(&pdev->dev,
 264                                 sizeof(struct press_state));
 265         if (!indio_dev)
 266                 return -ENOMEM;
 267         platform_set_drvdata(pdev, indio_dev);
 268
 269         press_state = iio_priv(indio_dev);
 270         press_state->common_attributes.hsdev = hsdev;
 271         press_state->common_attributes.pdev = pdev;
 272
 273         ret = hid_sensor_parse_common_attributes(hsdev,
 274                                         HID_USAGE_SENSOR_PRESSURE,
 275                                         &press_state->common_attributes);
 276         if (ret) {
 277                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 278                 return ret;
 279         }
 280
 281         indio_dev->channels = kmemdup(press_channels, sizeof(press_channels),
 282                                       GFP_KERNEL);
 283         if (!indio_dev->channels) {
 284                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 285                 return -ENOMEM;
 286         }
 287
 288         ret = press_parse_report(pdev, hsdev,
 289                                  (struct iio_chan_spec *)indio_dev->channels,
 290                                  HID_USAGE_SENSOR_PRESSURE, press_state);
 291         if (ret) {
 292                 dev_err(&pdev->dev, "failed to setup attributes\n");
 293                 goto error_free_dev_mem;
 294         }
 295
 296         indio_dev->num_channels =
 297                                 ARRAY_SIZE(press_channels);
 298         indio_dev->dev.parent = &pdev->dev;
 299         indio_dev->info = &press_info;
 300         indio_dev->name = name;
 301         indio_dev->modes = INDIO_DIRECT_MODE;
 302
 303         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 304                 NULL, NULL);
 305         if (ret) {
 306                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 307                 goto error_free_dev_mem;
 308         }
 309         atomic_set(&press_state->common_attributes.data_ready, 0);
 310         ret = hid_sensor_setup_trigger(indio_dev, name,
 311                                 &press_state->common_attributes);
 312         if (ret) {
 313                 dev_err(&pdev->dev, "trigger setup failed\n");
 314                 goto error_unreg_buffer_funcs;
 315         }
 316
 317         ret = iio_device_register(indio_dev);
 318         if (ret) {
 319                 dev_err(&pdev->dev, "device register failed\n");
 320                 goto error_remove_trigger;
 321         }
 322
 323         press_state->callbacks.send_event = press_proc_event;
 324         press_state->callbacks.capture_sample = press_capture_sample;
 325         press_state->callbacks.pdev = pdev;
 326         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
 327                                         &press_state->callbacks);
 328         if (ret < 0) {
 329                 dev_err(&pdev->dev, "callback reg failed\n");
 330                 goto error_iio_unreg;
 331         }
 332
 333         return ret;
 334
 335 error_iio_unreg:
 336         iio_device_unregister(indio_dev);
 337 error_remove_trigger:
 338         hid_sensor_remove_trigger(&press_state->common_attributes);
 339 error_unreg_buffer_funcs:
 340         iio_triggered_buffer_cleanup(indio_dev);
 341 error_free_dev_mem:
 342         kfree(indio_dev->channels);
 343         return ret;
 344 }
 345
 346 /* Function to deinitialize the processing for usage id */
 347 static int hid_press_remove(struct platform_device *pdev)
 348 {
 349         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 350         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 351         struct press_state *press_state = iio_priv(indio_dev);
 352
 353         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
 354         iio_device_unregister(indio_dev);
 355         hid_sensor_remove_trigger(&press_state->common_attributes);
 356         iio_triggered_buffer_cleanup(indio_dev);
 357         kfree(indio_dev->channels);
 358
 359         return 0;
 360 }
 361
 362 static const struct platform_device_id hid_press_ids[] = {
 363         {
 364                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 365                 .name = "HID-SENSOR-200031",
 366         },
 367         { /* sentinel */ }
 368 };
 369 MODULE_DEVICE_TABLE(platform, hid_press_ids);
 370
 371 static struct platform_driver hid_press_platform_driver = {
 372         .id_table = hid_press_ids,
 373         .driver = {
 374                 .name   = KBUILD_MODNAME,
 375                 .pm     = &hid_sensor_pm_ops,
 376         },
 377         .probe          = hid_press_probe,
 378         .remove         = hid_press_remove,
 379 };
 380 module_platform_driver(hid_press_platform_driver);
 381
 382 MODULE_DESCRIPTION("HID Sensor Pressure");
 383 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
 384 MODULE_LICENSE("GPL");