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/hid-sensor-hub.h>
  25 #include <linux/iio/iio.h>
  26 #include <linux/iio/sysfs.h>
  27 #include <linux/iio/buffer.h>
  28 #include <linux/iio/trigger_consumer.h>
  29 #include <linux/iio/triggered_buffer.h>
  30 #include "../common/hid-sensors/hid-sensor-trigger.h"
  31
  32 #define CHANNEL_SCAN_INDEX_PRESSURE 0
  33
  34 struct press_state {
  35         struct hid_sensor_hub_callbacks callbacks;
  36         struct hid_sensor_common common_attributes;
  37         struct hid_sensor_hub_attribute_info press_attr;
  38         u32 press_data;
  39 };
  40
  41 /* Channel definitions */
  42 static const struct iio_chan_spec press_channels[] = {
  43         {
  44                 .type = IIO_PRESSURE,
  45                 .modified = 1,
  46                 .channel2 = IIO_NO_MOD,
  47                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  48                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  49                 BIT(IIO_CHAN_INFO_SCALE) |
  50                 BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  51                 BIT(IIO_CHAN_INFO_HYSTERESIS),
  52                 .scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
  53         }
  54 };
  55
  56 /* Adjust channel real bits based on report descriptor */
  57 static void press_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  58                                         int channel, int size)
  59 {
  60         channels[channel].scan_type.sign = 's';
  61         /* Real storage bits will change based on the report desc. */
  62         channels[channel].scan_type.realbits = size * 8;
  63         /* Maximum size of a sample to capture is u32 */
  64         channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  65 }
  66
  67 /* Channel read_raw handler */
  68 static int press_read_raw(struct iio_dev *indio_dev,
  69                               struct iio_chan_spec const *chan,
  70                               int *val, int *val2,
  71                               long mask)
  72 {
  73         struct press_state *press_state = iio_priv(indio_dev);
  74         int report_id = -1;
  75         u32 address;
  76         int ret;
  77         int ret_type;
  78
  79         *val = 0;
  80         *val2 = 0;
  81         switch (mask) {
  82         case IIO_CHAN_INFO_RAW:
  83                 switch (chan->scan_index) {
  84                 case  CHANNEL_SCAN_INDEX_PRESSURE:
  85                         report_id = press_state->press_attr.report_id;
  86                         address =
  87                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
  88                         break;
  89                 default:
  90                         report_id = -1;
  91                         break;
  92                 }
  93                 if (report_id >= 0)
  94                         *val = sensor_hub_input_attr_get_raw_value(
  95                                 press_state->common_attributes.hsdev,
  96                                 HID_USAGE_SENSOR_PRESSURE, address,
  97                                 report_id);
  98                 else {
  99                         *val = 0;
 100                         return -EINVAL;
 101                 }
 102                 ret_type = IIO_VAL_INT;
 103                 break;
 104         case IIO_CHAN_INFO_SCALE:
 105                 *val = press_state->press_attr.units;
 106                 ret_type = IIO_VAL_INT;
 107                 break;
 108         case IIO_CHAN_INFO_OFFSET:
 109                 *val = hid_sensor_convert_exponent(
 110                                 press_state->press_attr.unit_expo);
 111                 ret_type = IIO_VAL_INT;
 112                 break;
 113         case IIO_CHAN_INFO_SAMP_FREQ:
 114                 ret = hid_sensor_read_samp_freq_value(
 115                                 &press_state->common_attributes, val, val2);
 116                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 117                 break;
 118         case IIO_CHAN_INFO_HYSTERESIS:
 119                 ret = hid_sensor_read_raw_hyst_value(
 120                                 &press_state->common_attributes, val, val2);
 121                 ret_type = IIO_VAL_INT_PLUS_MICRO;
 122                 break;
 123         default:
 124                 ret_type = -EINVAL;
 125                 break;
 126         }
 127
 128         return ret_type;
 129 }
 130
 131 /* Channel write_raw handler */
 132 static int press_write_raw(struct iio_dev *indio_dev,
 133                                struct iio_chan_spec const *chan,
 134                                int val,
 135                                int val2,
 136                                long mask)
 137 {
 138         struct press_state *press_state = iio_priv(indio_dev);
 139         int ret = 0;
 140
 141         switch (mask) {
 142         case IIO_CHAN_INFO_SAMP_FREQ:
 143                 ret = hid_sensor_write_samp_freq_value(
 144                                 &press_state->common_attributes, val, val2);
 145                 break;
 146         case IIO_CHAN_INFO_HYSTERESIS:
 147                 ret = hid_sensor_write_raw_hyst_value(
 148                                 &press_state->common_attributes, val, val2);
 149                 break;
 150         default:
 151                 ret = -EINVAL;
 152         }
 153
 154         return ret;
 155 }
 156
 157 static const struct iio_info press_info = {
 158         .driver_module = THIS_MODULE,
 159         .read_raw = &press_read_raw,
 160         .write_raw = &press_write_raw,
 161 };
 162
 163 /* Function to push data to buffer */
 164 static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 165                                         int len)
 166 {
 167         dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 168         iio_push_to_buffers(indio_dev, data);
 169 }
 170
 171 /* Callback handler to send event after all samples are received and captured */
 172 static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 173                                 unsigned usage_id,
 174                                 void *priv)
 175 {
 176         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 177         struct press_state *press_state = iio_priv(indio_dev);
 178
 179         dev_dbg(&indio_dev->dev, "press_proc_event [%d]\n",
 180                                 press_state->common_attributes.data_ready);
 181         if (press_state->common_attributes.data_ready)
 182                 hid_sensor_push_data(indio_dev,
 183                                 &press_state->press_data,
 184                                 sizeof(press_state->press_data));
 185
 186         return 0;
 187 }
 188
 189 /* Capture samples in local storage */
 190 static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
 191                                 unsigned usage_id,
 192                                 size_t raw_len, char *raw_data,
 193                                 void *priv)
 194 {
 195         struct iio_dev *indio_dev = platform_get_drvdata(priv);
 196         struct press_state *press_state = iio_priv(indio_dev);
 197         int ret = -EINVAL;
 198
 199         switch (usage_id) {
 200         case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
 201                 press_state->press_data = *(u32 *)raw_data;
 202                 ret = 0;
 203                 break;
 204         default:
 205                 break;
 206         }
 207
 208         return ret;
 209 }
 210
 211 /* Parse report which is specific to an usage id*/
 212 static int press_parse_report(struct platform_device *pdev,
 213                                 struct hid_sensor_hub_device *hsdev,
 214                                 struct iio_chan_spec *channels,
 215                                 unsigned usage_id,
 216                                 struct press_state *st)
 217 {
 218         int ret;
 219
 220         ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 221                         usage_id,
 222                         HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
 223                         &st->press_attr);
 224         if (ret < 0)
 225                 return ret;
 226         press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
 227                                         st->press_attr.size);
 228
 229         dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
 230                         st->press_attr.report_id);
 231
 232         /* Set Sensitivity field ids, when there is no individual modifier */
 233         if (st->common_attributes.sensitivity.index < 0) {
 234                 sensor_hub_input_get_attribute_info(hsdev,
 235                         HID_FEATURE_REPORT, usage_id,
 236                         HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 237                         HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
 238                         &st->common_attributes.sensitivity);
 239                 dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 240                         st->common_attributes.sensitivity.index,
 241                         st->common_attributes.sensitivity.report_id);
 242         }
 243         return ret;
 244 }
 245
 246 /* Function to initialize the processing for usage id */
 247 static int hid_press_probe(struct platform_device *pdev)
 248 {
 249         int ret = 0;
 250         static const char *name = "press";
 251         struct iio_dev *indio_dev;
 252         struct press_state *press_state;
 253         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 254         struct iio_chan_spec *channels;
 255
 256         indio_dev = devm_iio_device_alloc(&pdev->dev,
 257                                 sizeof(struct press_state));
 258         if (!indio_dev)
 259                 return -ENOMEM;
 260         platform_set_drvdata(pdev, indio_dev);
 261
 262         press_state = iio_priv(indio_dev);
 263         press_state->common_attributes.hsdev = hsdev;
 264         press_state->common_attributes.pdev = pdev;
 265
 266         ret = hid_sensor_parse_common_attributes(hsdev,
 267                                         HID_USAGE_SENSOR_PRESSURE,
 268                                         &press_state->common_attributes);
 269         if (ret) {
 270                 dev_err(&pdev->dev, "failed to setup common attributes\n");
 271                 return ret;
 272         }
 273
 274         channels = kmemdup(press_channels, sizeof(press_channels), GFP_KERNEL);
 275         if (!channels) {
 276                 dev_err(&pdev->dev, "failed to duplicate channels\n");
 277                 return -ENOMEM;
 278         }
 279
 280         ret = press_parse_report(pdev, hsdev, channels,
 281                                 HID_USAGE_SENSOR_PRESSURE, press_state);
 282         if (ret) {
 283                 dev_err(&pdev->dev, "failed to setup attributes\n");
 284                 goto error_free_dev_mem;
 285         }
 286
 287         indio_dev->channels = channels;
 288         indio_dev->num_channels =
 289                                 ARRAY_SIZE(press_channels);
 290         indio_dev->dev.parent = &pdev->dev;
 291         indio_dev->info = &press_info;
 292         indio_dev->name = name;
 293         indio_dev->modes = INDIO_DIRECT_MODE;
 294
 295         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 296                 NULL, NULL);
 297         if (ret) {
 298                 dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 299                 goto error_free_dev_mem;
 300         }
 301         press_state->common_attributes.data_ready = false;
 302         ret = hid_sensor_setup_trigger(indio_dev, name,
 303                                 &press_state->common_attributes);
 304         if (ret) {
 305                 dev_err(&pdev->dev, "trigger setup failed\n");
 306                 goto error_unreg_buffer_funcs;
 307         }
 308
 309         ret = iio_device_register(indio_dev);
 310         if (ret) {
 311                 dev_err(&pdev->dev, "device register failed\n");
 312                 goto error_remove_trigger;
 313         }
 314
 315         press_state->callbacks.send_event = press_proc_event;
 316         press_state->callbacks.capture_sample = press_capture_sample;
 317         press_state->callbacks.pdev = pdev;
 318         ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
 319                                         &press_state->callbacks);
 320         if (ret < 0) {
 321                 dev_err(&pdev->dev, "callback reg failed\n");
 322                 goto error_iio_unreg;
 323         }
 324
 325         return ret;
 326
 327 error_iio_unreg:
 328         iio_device_unregister(indio_dev);
 329 error_remove_trigger:
 330         hid_sensor_remove_trigger(&press_state->common_attributes);
 331 error_unreg_buffer_funcs:
 332         iio_triggered_buffer_cleanup(indio_dev);
 333 error_free_dev_mem:
 334         kfree(indio_dev->channels);
 335         return ret;
 336 }
 337
 338 /* Function to deinitialize the processing for usage id */
 339 static int hid_press_remove(struct platform_device *pdev)
 340 {
 341         struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 342         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 343         struct press_state *press_state = iio_priv(indio_dev);
 344
 345         sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
 346         iio_device_unregister(indio_dev);
 347         hid_sensor_remove_trigger(&press_state->common_attributes);
 348         iio_triggered_buffer_cleanup(indio_dev);
 349         kfree(indio_dev->channels);
 350
 351         return 0;
 352 }
 353
 354 static struct platform_device_id hid_press_ids[] = {
 355         {
 356                 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 357                 .name = "HID-SENSOR-200031",
 358         },
 359         { /* sentinel */ }
 360 };
 361 MODULE_DEVICE_TABLE(platform, hid_press_ids);
 362
 363 static struct platform_driver hid_press_platform_driver = {
 364         .id_table = hid_press_ids,
 365         .driver = {
 366                 .name   = KBUILD_MODNAME,
 367                 .owner  = THIS_MODULE,
 368         },
 369         .probe          = hid_press_probe,
 370         .remove         = hid_press_remove,
 371 };
 372 module_platform_driver(hid_press_platform_driver);
 373
 374 MODULE_DESCRIPTION("HID Sensor Pressure");
 375 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
 376 MODULE_LICENSE("GPL");