linux/drivers/iio/pressure/hid-sensor-press.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * HID Sensors Driver
   4 * Copyright (c) 2014, Intel Corporation.
   5 */
   6#include <linux/device.h>
   7#include <linux/platform_device.h>
   8#include <linux/module.h>
   9#include <linux/mod_devicetable.h>
  10#include <linux/slab.h>
  11#include <linux/hid-sensor-hub.h>
  12#include <linux/iio/iio.h>
  13#include <linux/iio/buffer.h>
  14#include "../common/hid-sensors/hid-sensor-trigger.h"
  15
  16enum {
  17        CHANNEL_SCAN_INDEX_PRESSURE,
  18        CHANNEL_SCAN_INDEX_TIMESTAMP,
  19};
  20
  21struct press_state {
  22        struct hid_sensor_hub_callbacks callbacks;
  23        struct hid_sensor_common common_attributes;
  24        struct hid_sensor_hub_attribute_info press_attr;
  25        struct {
  26                u32 press_data;
  27                u64 timestamp __aligned(8);
  28        } scan;
  29        int scale_pre_decml;
  30        int scale_post_decml;
  31        int scale_precision;
  32        int value_offset;
  33        s64 timestamp;
  34};
  35
  36static const u32 press_sensitivity_addresses[] = {
  37        HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
  38        HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE
  39};
  40
  41/* Channel definitions */
  42static const struct iio_chan_spec press_channels[] = {
  43        {
  44                .type = IIO_PRESSURE,
  45                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  46                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  47                BIT(IIO_CHAN_INFO_SCALE) |
  48                BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  49                BIT(IIO_CHAN_INFO_HYSTERESIS),
  50                .scan_index = CHANNEL_SCAN_INDEX_PRESSURE,
  51        },
  52        IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
  53
  54};
  55
  56/* Adjust channel real bits based on report descriptor */
  57static 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 */
  68static 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_type;
  77        s32 min;
  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                        min = press_state->press_attr.logical_minimum;
  87                        address = HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
  88                        break;
  89                default:
  90                        report_id = -1;
  91                        break;
  92                }
  93                if (report_id >= 0) {
  94                        hid_sensor_power_state(&press_state->common_attributes,
  95                                                true);
  96                        *val = sensor_hub_input_attr_get_raw_value(
  97                                press_state->common_attributes.hsdev,
  98                                HID_USAGE_SENSOR_PRESSURE, address,
  99                                report_id,
 100                                SENSOR_HUB_SYNC,
 101                                min < 0);
 102                        hid_sensor_power_state(&press_state->common_attributes,
 103                                                false);
 104                } else {
 105                        *val = 0;
 106                        return -EINVAL;
 107                }
 108                ret_type = IIO_VAL_INT;
 109                break;
 110        case IIO_CHAN_INFO_SCALE:
 111                *val = press_state->scale_pre_decml;
 112                *val2 = press_state->scale_post_decml;
 113                ret_type = press_state->scale_precision;
 114                break;
 115        case IIO_CHAN_INFO_OFFSET:
 116                *val = press_state->value_offset;
 117                ret_type = IIO_VAL_INT;
 118                break;
 119        case IIO_CHAN_INFO_SAMP_FREQ:
 120                ret_type = hid_sensor_read_samp_freq_value(
 121                                &press_state->common_attributes, val, val2);
 122                break;
 123        case IIO_CHAN_INFO_HYSTERESIS:
 124                ret_type = hid_sensor_read_raw_hyst_value(
 125                                &press_state->common_attributes, val, val2);
 126                break;
 127        default:
 128                ret_type = -EINVAL;
 129                break;
 130        }
 131
 132        return ret_type;
 133}
 134
 135/* Channel write_raw handler */
 136static int press_write_raw(struct iio_dev *indio_dev,
 137                               struct iio_chan_spec const *chan,
 138                               int val,
 139                               int val2,
 140                               long mask)
 141{
 142        struct press_state *press_state = iio_priv(indio_dev);
 143        int ret = 0;
 144
 145        switch (mask) {
 146        case IIO_CHAN_INFO_SAMP_FREQ:
 147                ret = hid_sensor_write_samp_freq_value(
 148                                &press_state->common_attributes, val, val2);
 149                break;
 150        case IIO_CHAN_INFO_HYSTERESIS:
 151                ret = hid_sensor_write_raw_hyst_value(
 152                                &press_state->common_attributes, val, val2);
 153                break;
 154        default:
 155                ret = -EINVAL;
 156        }
 157
 158        return ret;
 159}
 160
 161static const struct iio_info press_info = {
 162        .read_raw = &press_read_raw,
 163        .write_raw = &press_write_raw,
 164};
 165
 166/* Callback handler to send event after all samples are received and captured */
 167static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 168                                unsigned usage_id,
 169                                void *priv)
 170{
 171        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 172        struct press_state *press_state = iio_priv(indio_dev);
 173
 174        dev_dbg(&indio_dev->dev, "press_proc_event\n");
 175        if (atomic_read(&press_state->common_attributes.data_ready)) {
 176                if (!press_state->timestamp)
 177                        press_state->timestamp = iio_get_time_ns(indio_dev);
 178
 179                iio_push_to_buffers_with_timestamp(
 180                        indio_dev, &press_state->scan, press_state->timestamp);
 181        }
 182
 183        return 0;
 184}
 185
 186/* Capture samples in local storage */
 187static int press_capture_sample(struct hid_sensor_hub_device *hsdev,
 188                                unsigned usage_id,
 189                                size_t raw_len, char *raw_data,
 190                                void *priv)
 191{
 192        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 193        struct press_state *press_state = iio_priv(indio_dev);
 194        int ret = -EINVAL;
 195
 196        switch (usage_id) {
 197        case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
 198                press_state->scan.press_data = *(u32 *)raw_data;
 199                ret = 0;
 200                break;
 201        case HID_USAGE_SENSOR_TIME_TIMESTAMP:
 202                press_state->timestamp = hid_sensor_convert_timestamp(
 203                        &press_state->common_attributes, *(s64 *)raw_data);
 204                break;
 205        default:
 206                break;
 207        }
 208
 209        return ret;
 210}
 211
 212/* Parse report which is specific to an usage id*/
 213static int press_parse_report(struct platform_device *pdev,
 214                                struct hid_sensor_hub_device *hsdev,
 215                                struct iio_chan_spec *channels,
 216                                unsigned usage_id,
 217                                struct press_state *st)
 218{
 219        int ret;
 220
 221        ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 222                        usage_id,
 223                        HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
 224                        &st->press_attr);
 225        if (ret < 0)
 226                return ret;
 227        press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
 228                                        st->press_attr.size);
 229
 230        dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
 231                        st->press_attr.report_id);
 232
 233        st->scale_precision = hid_sensor_format_scale(
 234                                HID_USAGE_SENSOR_PRESSURE,
 235                                &st->press_attr,
 236                                &st->scale_pre_decml, &st->scale_post_decml);
 237
 238        return ret;
 239}
 240
 241/* Function to initialize the processing for usage id */
 242static int hid_press_probe(struct platform_device *pdev)
 243{
 244        int ret = 0;
 245        static const char *name = "press";
 246        struct iio_dev *indio_dev;
 247        struct press_state *press_state;
 248        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 249
 250        indio_dev = devm_iio_device_alloc(&pdev->dev,
 251                                sizeof(struct press_state));
 252        if (!indio_dev)
 253                return -ENOMEM;
 254        platform_set_drvdata(pdev, indio_dev);
 255
 256        press_state = iio_priv(indio_dev);
 257        press_state->common_attributes.hsdev = hsdev;
 258        press_state->common_attributes.pdev = pdev;
 259
 260        ret = hid_sensor_parse_common_attributes(hsdev,
 261                                        HID_USAGE_SENSOR_PRESSURE,
 262                                        &press_state->common_attributes,
 263                                        press_sensitivity_addresses,
 264                                        ARRAY_SIZE(press_sensitivity_addresses));
 265        if (ret) {
 266                dev_err(&pdev->dev, "failed to setup common attributes\n");
 267                return ret;
 268        }
 269
 270        indio_dev->channels = devm_kmemdup(&pdev->dev, press_channels,
 271                                           sizeof(press_channels), GFP_KERNEL);
 272        if (!indio_dev->channels) {
 273                dev_err(&pdev->dev, "failed to duplicate channels\n");
 274                return -ENOMEM;
 275        }
 276
 277        ret = press_parse_report(pdev, hsdev,
 278                                 (struct iio_chan_spec *)indio_dev->channels,
 279                                 HID_USAGE_SENSOR_PRESSURE, press_state);
 280        if (ret) {
 281                dev_err(&pdev->dev, "failed to setup attributes\n");
 282                return ret;
 283        }
 284
 285        indio_dev->num_channels =
 286                                ARRAY_SIZE(press_channels);
 287        indio_dev->info = &press_info;
 288        indio_dev->name = name;
 289        indio_dev->modes = INDIO_DIRECT_MODE;
 290
 291        atomic_set(&press_state->common_attributes.data_ready, 0);
 292
 293        ret = hid_sensor_setup_trigger(indio_dev, name,
 294                                &press_state->common_attributes);
 295        if (ret) {
 296                dev_err(&pdev->dev, "trigger setup failed\n");
 297                return ret;
 298        }
 299
 300        ret = iio_device_register(indio_dev);
 301        if (ret) {
 302                dev_err(&pdev->dev, "device register failed\n");
 303                goto error_remove_trigger;
 304        }
 305
 306        press_state->callbacks.send_event = press_proc_event;
 307        press_state->callbacks.capture_sample = press_capture_sample;
 308        press_state->callbacks.pdev = pdev;
 309        ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
 310                                        &press_state->callbacks);
 311        if (ret < 0) {
 312                dev_err(&pdev->dev, "callback reg failed\n");
 313                goto error_iio_unreg;
 314        }
 315
 316        return ret;
 317
 318error_iio_unreg:
 319        iio_device_unregister(indio_dev);
 320error_remove_trigger:
 321        hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
 322        return ret;
 323}
 324
 325/* Function to deinitialize the processing for usage id */
 326static int hid_press_remove(struct platform_device *pdev)
 327{
 328        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 329        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 330        struct press_state *press_state = iio_priv(indio_dev);
 331
 332        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
 333        iio_device_unregister(indio_dev);
 334        hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
 335
 336        return 0;
 337}
 338
 339static const struct platform_device_id hid_press_ids[] = {
 340        {
 341                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 342                .name = "HID-SENSOR-200031",
 343        },
 344        { /* sentinel */ }
 345};
 346MODULE_DEVICE_TABLE(platform, hid_press_ids);
 347
 348static struct platform_driver hid_press_platform_driver = {
 349        .id_table = hid_press_ids,
 350        .driver = {
 351                .name   = KBUILD_MODNAME,
 352                .pm     = &hid_sensor_pm_ops,
 353        },
 354        .probe          = hid_press_probe,
 355        .remove         = hid_press_remove,
 356};
 357module_platform_driver(hid_press_platform_driver);
 358
 359MODULE_DESCRIPTION("HID Sensor Pressure");
 360MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
 361MODULE_LICENSE("GPL");
 362MODULE_IMPORT_NS(IIO_HID);
 363