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         .driver_module = THIS_MODULE,
 164         .read_raw = &press_read_raw,
 165         .write_raw = &press_write_raw,
 166 };
 167
 168 /* Function to push data to buffer */
 169 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 170                                         int len)
 171 {
 172         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 173         iio_push_to_buffers(indio_dev, data);
 174 }
 175
 176 /* Callback handler to send event after all samples are received and captured */
 177 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 178                                 unsigned usage_id,
 179                                 void *priv)
 180 {
 181         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 182         struct press_state *press_state = iio_priv(indio_dev);
 183
 184         dev_dbg(&indio_dev->dev, "press_proc_event\n");
 185         if (atomic_read(&press_state->common_attributes.data_ready))
 186                 hid_sensor_push_data(indio_dev,
 187                                 &press_state->press_data,
 188                                 sizeof(press_state->press_data));
 189
 190         return 0;
 191 }
 192
 193 /* Capture samples in local storage */
 194 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
 195                                 unsigned usage_id,
 196                                 size_t raw_len, char *raw_data,
 197                                 void *priv)
 198 {
 199         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 200         struct press_state *press_state = iio_priv(indio_dev);
 201         int ret = -EINVAL;
 202
 203         switch (usage_id) {
 204         case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
 205                 press_state->press_data = *(u32 *)raw_data;
 206                 ret = 0;
 207                 break;
 208         default:
 209                 break;
 210         }
 211
 212         return ret;
 213 }
 214
 215 /* Parse report which is specific to an usage id*/
 216 static int press_parse_report(struct platform_device *pdev,
 217                                 struct hid_sensor_hub_device *hsdev,
 218                                 struct iio_chan_spec *channels,
 219                                 unsigned usage_id,
 220                                 struct press_state *st)
 221 {
 222         int ret;
 223
 224         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 225                         usage_id,
 226                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
 227                         &st->press_attr);
 228         if (ret < 0)
 229                 return ret;
 230         press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
 231                                         st->press_attr.size);
 232
 233         dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
 234                         st->press_attr.report_id);
 235
 236         st->scale_precision = hid_sensor_format_scale(
 237                                 HID_USAGE_SENSOR_PRESSURE,
 238                                 &st->press_attr,
 239                                 &st->scale_pre_decml, &st->scale_post_decml);
 240
 241         /* Set Sensitivity field ids, when there is no individual modifier */
 242         if (st->common_attributes.sensitivity.index < 0) {
 243                 sensor_hub_input_get_attribute_info(hsdev,
 244                         HID_FEATURE_REPORT, usage_id,
 245                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 246                         HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
 247                         &st->common_attributes.sensitivity);
 248                 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 249                         st->common_attributes.sensitivity.index,
 250                         st->common_attributes.sensitivity.report_id);
 251         }
 252         return ret;
 253 }
 254
 255 /* Function to initialize the processing for usage id */
 256 static int hid_press_probe(struct platform_device *pdev)
 257 {
 258         int ret = 0;
 259         static const char *name = "press";
 260         struct iio_dev *indio_dev;
 261         struct press_state *press_state;
 262         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 263
 264         indio_dev = devm_iio_device_alloc(&pdev->dev,
 265                                 sizeof(struct press_state));
 266         if (!indio_dev)
 267                 return -ENOMEM;
 268         platform_set_drvdata(pdev, indio_dev);
 269
 270         press_state = iio_priv(indio_dev);
 271         press_state->common_attributes.hsdev = hsdev;
 272         press_state->common_attributes.pdev = pdev;
 273
 274         ret = hid_sensor_parse_common_attributes(hsdev,
 275                                         HID_USAGE_SENSOR_PRESSURE,
 276                                         &press_state->common_attributes);
 277         if (ret) {
 278                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 279                 return ret;
 280         }
 281
 282         indio_dev->channels = kmemdup(press_channels, sizeof(press_channels),
 283                                       GFP_KERNEL);
 284         if (!indio_dev->channels) {
 285                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 286                 return -ENOMEM;
 287         }
 288
 289         ret = press_parse_report(pdev, hsdev,
 290                                  (struct iio_chan_spec *)indio_dev->channels,
 291                                  HID_USAGE_SENSOR_PRESSURE, press_state);
 292         if (ret) {
 293                 dev_err(&pdev->dev, "failed to setup attributes\n");
 294                 goto error_free_dev_mem;
 295         }
 296
 297         indio_dev->num_channels =
 298                                 ARRAY_SIZE(press_channels);
 299         indio_dev->dev.parent = &pdev->dev;
 300         indio_dev->info = &press_info;
 301         indio_dev->name = name;
 302         indio_dev->modes = INDIO_DIRECT_MODE;
 303
 304         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 305                 NULL, NULL);
 306         if (ret) {
 307                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 308                 goto error_free_dev_mem;
 309         }
 310         atomic_set(&press_state->common_attributes.data_ready, 0);
 311         ret = hid_sensor_setup_trigger(indio_dev, name,
 312                                 &press_state->common_attributes);
 313         if (ret) {
 314                 dev_err(&pdev->dev, "trigger setup failed\n");
 315                 goto error_unreg_buffer_funcs;
 316         }
 317
 318         ret = iio_device_register(indio_dev);
 319         if (ret) {
 320                 dev_err(&pdev->dev, "device register failed\n");
 321                 goto error_remove_trigger;
 322         }
 323
 324         press_state->callbacks.send_event = press_proc_event;
 325         press_state->callbacks.capture_sample = press_capture_sample;
 326         press_state->callbacks.pdev = pdev;
 327         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
 328                                         &press_state->callbacks);
 329         if (ret < 0) {
 330                 dev_err(&pdev->dev, "callback reg failed\n");
 331                 goto error_iio_unreg;
 332         }
 333
 334         return ret;
 335
 336 error_iio_unreg:
 337         iio_device_unregister(indio_dev);
 338 error_remove_trigger:
 339         hid_sensor_remove_trigger(&press_state->common_attributes);
 340 error_unreg_buffer_funcs:
 341         iio_triggered_buffer_cleanup(indio_dev);
 342 error_free_dev_mem:
 343         kfree(indio_dev->channels);
 344         return ret;
 345 }
 346
 347 /* Function to deinitialize the processing for usage id */
 348 static int hid_press_remove(struct platform_device *pdev)
 349 {
 350         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 351         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 352         struct press_state *press_state = iio_priv(indio_dev);
 353
 354         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
 355         iio_device_unregister(indio_dev);
 356         hid_sensor_remove_trigger(&press_state->common_attributes);
 357         iio_triggered_buffer_cleanup(indio_dev);
 358         kfree(indio_dev->channels);
 359
 360         return 0;
 361 }
 362
 363 static const struct platform_device_id hid_press_ids[] = {
 364         {
 365                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 366                 .name = "HID-SENSOR-200031",
 367         },
 368         { /* sentinel */ }
 369 };
 370 MODULE_DEVICE_TABLE(platform, hid_press_ids);
 371
 372 static struct platform_driver hid_press_platform_driver = {
 373         .id_table = hid_press_ids,
 374         .driver = {
 375                 .name   = KBUILD_MODNAME,
 376                 .pm     = &hid_sensor_pm_ops,
 377         },
 378         .probe          = hid_press_probe,
 379         .remove         = hid_press_remove,
 380 };
 381 module_platform_driver(hid_press_platform_driver);
 382
 383 MODULE_DESCRIPTION("HID Sensor Pressure");
 384 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
 385 MODULE_LICENSE("GPL");