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