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                 .modified = 1,
  51                 .channel2 = IIO_NO_MOD,
  52                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  53                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  54                 BIT(IIO_CHAN_INFO_SCALE) |
  55                 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  56                 BIT(IIO_CHAN_INFO_HYSTERESIS),
  57                 .scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
  58         }
  59 };
  60
  61 /* Adjust channel real bits based on report descriptor */
  62 static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  63                                         int channel, int size)
  64 {
  65         channels[channel].scan_type.sign = 's';
  66         /* Real storage bits will change based on the report desc. */
  67         channels[channel].scan_type.realbits = size * 8;
  68         /* Maximum size of a sample to capture is u32 */
  69         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  70 }
  71
  72 /* Channel read_raw handler */
  73 static int press_read_raw(struct iio_dev *indio_dev,
  74                               struct iio_chan_spec const *chan,
  75                               int *val, int *val2,
  76                               long mask)
  77 {
  78         struct press_state *press_state = iio_priv(indio_dev);
  79         int report_id = -1;
  80         u32 address;
  81         int ret;
  82         int ret_type;
  83         s32 poll_value;
  84
  85         *val = 0;
  86         *val2 = 0;
  87         switch (mask) {
  88         case IIO_CHAN_INFO_RAW:
  89                 switch (chan->scan_index) {
  90                 case  CHANNEL_SCAN_INDEX_PRESSURE:
  91                         report_id = press_state->press_attr.report_id;
  92                         address =
  93                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
  94                         break;
  95                 default:
  96                         report_id = -1;
  97                         break;
  98                 }
  99                 if (report_id >= 0) {
 100                         poll_value = hid_sensor_read_poll_value(
 101                                         &press_state->common_attributes);
 102                         if (poll_value < 0)
 103                                 return -EINVAL;
 104                         hid_sensor_power_state(&press_state->common_attributes,
 105                                                 true);
 106
 107                         msleep_interruptible(poll_value * 2);
 108
 109                         *val = sensor_hub_input_attr_get_raw_value(
 110                                 press_state->common_attributes.hsdev,
 111                                 HID_USAGE_SENSOR_PRESSURE, address,
 112                                 report_id);
 113                         hid_sensor_power_state(&press_state->common_attributes,
 114                                                 false);
 115                 } else {
 116                         *val = 0;
 117                         return -EINVAL;
 118                 }
 119                 ret_type = IIO_VAL_INT;
 120                 break;
 121         case IIO_CHAN_INFO_SCALE:
 122                 *val = press_state->scale_pre_decml;
 123                 *val2 = press_state->scale_post_decml;
 124                 ret_type = press_state->scale_precision;
 125                 break;
 126         case IIO_CHAN_INFO_OFFSET:
 127                 *val = press_state->value_offset;
 128                 ret_type = IIO_VAL_INT;
 129                 break;
 130         case IIO_CHAN_INFO_SAMP_FREQ:
 131                 ret = hid_sensor_read_samp_freq_value(
 132                                 &press_state->common_attributes, val, val2);
 133                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 134                 break;
 135         case IIO_CHAN_INFO_HYSTERESIS:
 136                 ret = hid_sensor_read_raw_hyst_value(
 137                                 &press_state->common_attributes, val, val2);
 138                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 139                 break;
 140         default:
 141                 ret_type = -EINVAL;
 142                 break;
 143         }
 144
 145         return ret_type;
 146 }
 147
 148 /* Channel write_raw handler */
 149 static int press_write_raw(struct iio_dev *indio_dev,
 150                                struct iio_chan_spec const *chan,
 151                                int val,
 152                                int val2,
 153                                long mask)
 154 {
 155         struct press_state *press_state = iio_priv(indio_dev);
 156         int ret = 0;
 157
 158         switch (mask) {
 159         case IIO_CHAN_INFO_SAMP_FREQ:
 160                 ret = hid_sensor_write_samp_freq_value(
 161                                 &press_state->common_attributes, val, val2);
 162                 break;
 163         case IIO_CHAN_INFO_HYSTERESIS:
 164                 ret = hid_sensor_write_raw_hyst_value(
 165                                 &press_state->common_attributes, val, val2);
 166                 break;
 167         default:
 168                 ret = -EINVAL;
 169         }
 170
 171         return ret;
 172 }
 173
 174 static const struct iio_info press_info = {
 175         .driver_module = THIS_MODULE,
 176         .read_raw = &press_read_raw,
 177         .write_raw = &press_write_raw,
 178 };
 179
 180 /* Function to push data to buffer */
 181 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 182                                         int len)
 183 {
 184         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 185         iio_push_to_buffers(indio_dev, data);
 186 }
 187
 188 /* Callback handler to send event after all samples are received and captured */
 189 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 190                                 unsigned usage_id,
 191                                 void *priv)
 192 {
 193         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 194         struct press_state *press_state = iio_priv(indio_dev);
 195
 196         dev_dbg(&indio_dev->dev, "press_proc_event\n");
 197         if (atomic_read(&press_state->common_attributes.data_ready))
 198                 hid_sensor_push_data(indio_dev,
 199                                 &press_state->press_data,
 200                                 sizeof(press_state->press_data));
 201
 202         return 0;
 203 }
 204
 205 /* Capture samples in local storage */
 206 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
 207                                 unsigned usage_id,
 208                                 size_t raw_len, char *raw_data,
 209                                 void *priv)
 210 {
 211         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 212         struct press_state *press_state = iio_priv(indio_dev);
 213         int ret = -EINVAL;
 214
 215         switch (usage_id) {
 216         case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
 217                 press_state->press_data = *(u32 *)raw_data;
 218                 ret = 0;
 219                 break;
 220         default:
 221                 break;
 222         }
 223
 224         return ret;
 225 }
 226
 227 /* Parse report which is specific to an usage id*/
 228 static int press_parse_report(struct platform_device *pdev,
 229                                 struct hid_sensor_hub_device *hsdev,
 230                                 struct iio_chan_spec *channels,
 231                                 unsigned usage_id,
 232                                 struct press_state *st)
 233 {
 234         int ret;
 235
 236         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 237                         usage_id,
 238                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
 239                         &st->press_attr);
 240         if (ret < 0)
 241                 return ret;
 242         press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
 243                                         st->press_attr.size);
 244
 245         dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
 246                         st->press_attr.report_id);
 247
 248         st->scale_precision = hid_sensor_format_scale(
 249                                 HID_USAGE_SENSOR_PRESSURE,
 250                                 &st->press_attr,
 251                                 &st->scale_pre_decml, &st->scale_post_decml);
 252
 253         /* Set Sensitivity field ids, when there is no individual modifier */
 254         if (st->common_attributes.sensitivity.index < 0) {
 255                 sensor_hub_input_get_attribute_info(hsdev,
 256                         HID_FEATURE_REPORT, usage_id,
 257                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 258                         HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
 259                         &st->common_attributes.sensitivity);
 260                 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 261                         st->common_attributes.sensitivity.index,
 262                         st->common_attributes.sensitivity.report_id);
 263         }
 264         return ret;
 265 }
 266
 267 /* Function to initialize the processing for usage id */
 268 static int hid_press_probe(struct platform_device *pdev)
 269 {
 270         int ret = 0;
 271         static const char *name = "press";
 272         struct iio_dev *indio_dev;
 273         struct press_state *press_state;
 274         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 275         struct iio_chan_spec *channels;
 276
 277         indio_dev = devm_iio_device_alloc(&pdev->dev,
 278                                 sizeof(struct press_state));
 279         if (!indio_dev)
 280                 return -ENOMEM;
 281         platform_set_drvdata(pdev, indio_dev);
 282
 283         press_state = iio_priv(indio_dev);
 284         press_state->common_attributes.hsdev = hsdev;
 285         press_state->common_attributes.pdev = pdev;
 286
 287         ret = hid_sensor_parse_common_attributes(hsdev,
 288                                         HID_USAGE_SENSOR_PRESSURE,
 289                                         &press_state->common_attributes);
 290         if (ret) {
 291                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 292                 return ret;
 293         }
 294
 295         channels = kmemdup(press_channels, sizeof(press_channels), GFP_KERNEL);
 296         if (!channels) {
 297                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 298                 return -ENOMEM;
 299         }
 300
 301         ret = press_parse_report(pdev, hsdev, channels,
 302                                 HID_USAGE_SENSOR_PRESSURE, press_state);
 303         if (ret) {
 304                 dev_err(&pdev->dev, "failed to setup attributes\n");
 305                 goto error_free_dev_mem;
 306         }
 307
 308         indio_dev->channels = channels;
 309         indio_dev->num_channels =
 310                                 ARRAY_SIZE(press_channels);
 311         indio_dev->dev.parent = &pdev->dev;
 312         indio_dev->info = &press_info;
 313         indio_dev->name = name;
 314         indio_dev->modes = INDIO_DIRECT_MODE;
 315
 316         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 317                 NULL, NULL);
 318         if (ret) {
 319                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 320                 goto error_free_dev_mem;
 321         }
 322         atomic_set(&press_state->common_attributes.data_ready, 0);
 323         ret = hid_sensor_setup_trigger(indio_dev, name,
 324                                 &press_state->common_attributes);
 325         if (ret) {
 326                 dev_err(&pdev->dev, "trigger setup failed\n");
 327                 goto error_unreg_buffer_funcs;
 328         }
 329
 330         ret = iio_device_register(indio_dev);
 331         if (ret) {
 332                 dev_err(&pdev->dev, "device register failed\n");
 333                 goto error_remove_trigger;
 334         }
 335
 336         press_state->callbacks.send_event = press_proc_event;
 337         press_state->callbacks.capture_sample = press_capture_sample;
 338         press_state->callbacks.pdev = pdev;
 339         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
 340                                         &press_state->callbacks);
 341         if (ret < 0) {
 342                 dev_err(&pdev->dev, "callback reg failed\n");
 343                 goto error_iio_unreg;
 344         }
 345
 346         return ret;
 347
 348 error_iio_unreg:
 349         iio_device_unregister(indio_dev);
 350 error_remove_trigger:
 351         hid_sensor_remove_trigger(&press_state->common_attributes);
 352 error_unreg_buffer_funcs:
 353         iio_triggered_buffer_cleanup(indio_dev);
 354 error_free_dev_mem:
 355         kfree(indio_dev->channels);
 356         return ret;
 357 }
 358
 359 /* Function to deinitialize the processing for usage id */
 360 static int hid_press_remove(struct platform_device *pdev)
 361 {
 362         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 363         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 364         struct press_state *press_state = iio_priv(indio_dev);
 365
 366         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
 367         iio_device_unregister(indio_dev);
 368         hid_sensor_remove_trigger(&press_state->common_attributes);
 369         iio_triggered_buffer_cleanup(indio_dev);
 370         kfree(indio_dev->channels);
 371
 372         return 0;
 373 }
 374
 375 static struct platform_device_id hid_press_ids[] = {
 376         {
 377                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 378                 .name = "HID-SENSOR-200031",
 379         },
 380         { /* sentinel */ }
 381 };
 382 MODULE_DEVICE_TABLE(platform, hid_press_ids);
 383
 384 static struct platform_driver hid_press_platform_driver = {
 385         .id_table = hid_press_ids,
 386         .driver = {
 387                 .name   = KBUILD_MODNAME,
 388                 .owner  = THIS_MODULE,
 389         },
 390         .probe          = hid_press_probe,
 391         .remove         = hid_press_remove,
 392 };
 393 module_platform_driver(hid_press_platform_driver);
 394
 395 MODULE_DESCRIPTION("HID Sensor Pressure");
 396 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
 397 MODULE_LICENSE("GPL");