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