linux/drivers/iio/light/hid-sensor-als.c
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   1/*
   2 * HID Sensors Driver
   3 * Copyright (c) 2012, 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; if not, write to the Free Software Foundation, Inc.,
  16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17 *
  18 */
  19#include <linux/device.h>
  20#include <linux/platform_device.h>
  21#include <linux/module.h>
  22#include <linux/interrupt.h>
  23#include <linux/irq.h>
  24#include <linux/slab.h>
  25#include <linux/delay.h>
  26#include <linux/hid-sensor-hub.h>
  27#include <linux/iio/iio.h>
  28#include <linux/iio/sysfs.h>
  29#include <linux/iio/buffer.h>
  30#include <linux/iio/trigger_consumer.h>
  31#include <linux/iio/triggered_buffer.h>
  32#include "../common/hid-sensors/hid-sensor-trigger.h"
  33
  34enum {
  35        CHANNEL_SCAN_INDEX_INTENSITY = 0,
  36        CHANNEL_SCAN_INDEX_ILLUM = 1,
  37        CHANNEL_SCAN_INDEX_MAX
  38};
  39
  40struct als_state {
  41        struct hid_sensor_hub_callbacks callbacks;
  42        struct hid_sensor_common common_attributes;
  43        struct hid_sensor_hub_attribute_info als_illum;
  44        u32 illum[CHANNEL_SCAN_INDEX_MAX];
  45        int scale_pre_decml;
  46        int scale_post_decml;
  47        int scale_precision;
  48        int value_offset;
  49};
  50
  51/* Channel definitions */
  52static const struct iio_chan_spec als_channels[] = {
  53        {
  54                .type = IIO_INTENSITY,
  55                .modified = 1,
  56                .channel2 = IIO_MOD_LIGHT_BOTH,
  57                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  58                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  59                BIT(IIO_CHAN_INFO_SCALE) |
  60                BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  61                BIT(IIO_CHAN_INFO_HYSTERESIS),
  62                .scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
  63        },
  64        {
  65                .type = IIO_LIGHT,
  66                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  67                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  68                BIT(IIO_CHAN_INFO_SCALE) |
  69                BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  70                BIT(IIO_CHAN_INFO_HYSTERESIS),
  71                .scan_index = CHANNEL_SCAN_INDEX_ILLUM,
  72        }
  73};
  74
  75/* Adjust channel real bits based on report descriptor */
  76static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
  77                                        int channel, int size)
  78{
  79        channels[channel].scan_type.sign = 's';
  80        /* Real storage bits will change based on the report desc. */
  81        channels[channel].scan_type.realbits = size * 8;
  82        /* Maximum size of a sample to capture is u32 */
  83        channels[channel].scan_type.storagebits = sizeof(u32) * 8;
  84}
  85
  86/* Channel read_raw handler */
  87static int als_read_raw(struct iio_dev *indio_dev,
  88                              struct iio_chan_spec const *chan,
  89                              int *val, int *val2,
  90                              long mask)
  91{
  92        struct als_state *als_state = iio_priv(indio_dev);
  93        int report_id = -1;
  94        u32 address;
  95        int ret_type;
  96
  97        *val = 0;
  98        *val2 = 0;
  99        switch (mask) {
 100        case 0:
 101                switch (chan->scan_index) {
 102                case  CHANNEL_SCAN_INDEX_INTENSITY:
 103                case  CHANNEL_SCAN_INDEX_ILLUM:
 104                        report_id = als_state->als_illum.report_id;
 105                        address =
 106                        HID_USAGE_SENSOR_LIGHT_ILLUM;
 107                        break;
 108                default:
 109                        report_id = -1;
 110                        break;
 111                }
 112                if (report_id >= 0) {
 113                        hid_sensor_power_state(&als_state->common_attributes,
 114                                                true);
 115                        *val = sensor_hub_input_attr_get_raw_value(
 116                                        als_state->common_attributes.hsdev,
 117                                        HID_USAGE_SENSOR_ALS, address,
 118                                        report_id,
 119                                        SENSOR_HUB_SYNC);
 120                        hid_sensor_power_state(&als_state->common_attributes,
 121                                                false);
 122                } else {
 123                        *val = 0;
 124                        return -EINVAL;
 125                }
 126                ret_type = IIO_VAL_INT;
 127                break;
 128        case IIO_CHAN_INFO_SCALE:
 129                *val = als_state->scale_pre_decml;
 130                *val2 = als_state->scale_post_decml;
 131                ret_type = als_state->scale_precision;
 132                break;
 133        case IIO_CHAN_INFO_OFFSET:
 134                *val = als_state->value_offset;
 135                ret_type = IIO_VAL_INT;
 136                break;
 137        case IIO_CHAN_INFO_SAMP_FREQ:
 138                ret_type = hid_sensor_read_samp_freq_value(
 139                                &als_state->common_attributes, val, val2);
 140                break;
 141        case IIO_CHAN_INFO_HYSTERESIS:
 142                ret_type = hid_sensor_read_raw_hyst_value(
 143                                &als_state->common_attributes, val, val2);
 144                break;
 145        default:
 146                ret_type = -EINVAL;
 147                break;
 148        }
 149
 150        return ret_type;
 151}
 152
 153/* Channel write_raw handler */
 154static int als_write_raw(struct iio_dev *indio_dev,
 155                               struct iio_chan_spec const *chan,
 156                               int val,
 157                               int val2,
 158                               long mask)
 159{
 160        struct als_state *als_state = iio_priv(indio_dev);
 161        int ret = 0;
 162
 163        switch (mask) {
 164        case IIO_CHAN_INFO_SAMP_FREQ:
 165                ret = hid_sensor_write_samp_freq_value(
 166                                &als_state->common_attributes, val, val2);
 167                break;
 168        case IIO_CHAN_INFO_HYSTERESIS:
 169                ret = hid_sensor_write_raw_hyst_value(
 170                                &als_state->common_attributes, val, val2);
 171                break;
 172        default:
 173                ret = -EINVAL;
 174        }
 175
 176        return ret;
 177}
 178
 179static const struct iio_info als_info = {
 180        .driver_module = THIS_MODULE,
 181        .read_raw = &als_read_raw,
 182        .write_raw = &als_write_raw,
 183};
 184
 185/* Function to push data to buffer */
 186static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
 187                                        int len)
 188{
 189        dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 190        iio_push_to_buffers(indio_dev, data);
 191}
 192
 193/* Callback handler to send event after all samples are received and captured */
 194static int als_proc_event(struct hid_sensor_hub_device *hsdev,
 195                                unsigned usage_id,
 196                                void *priv)
 197{
 198        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 199        struct als_state *als_state = iio_priv(indio_dev);
 200
 201        dev_dbg(&indio_dev->dev, "als_proc_event\n");
 202        if (atomic_read(&als_state->common_attributes.data_ready))
 203                hid_sensor_push_data(indio_dev,
 204                                &als_state->illum,
 205                                sizeof(als_state->illum));
 206
 207        return 0;
 208}
 209
 210/* Capture samples in local storage */
 211static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 212                                unsigned usage_id,
 213                                size_t raw_len, char *raw_data,
 214                                void *priv)
 215{
 216        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 217        struct als_state *als_state = iio_priv(indio_dev);
 218        int ret = -EINVAL;
 219        u32 sample_data = *(u32 *)raw_data;
 220
 221        switch (usage_id) {
 222        case HID_USAGE_SENSOR_LIGHT_ILLUM:
 223                als_state->illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
 224                als_state->illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
 225                ret = 0;
 226                break;
 227        default:
 228                break;
 229        }
 230
 231        return ret;
 232}
 233
 234/* Parse report which is specific to an usage id*/
 235static int als_parse_report(struct platform_device *pdev,
 236                                struct hid_sensor_hub_device *hsdev,
 237                                struct iio_chan_spec *channels,
 238                                unsigned usage_id,
 239                                struct als_state *st)
 240{
 241        int ret;
 242
 243        ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
 244                        usage_id,
 245                        HID_USAGE_SENSOR_LIGHT_ILLUM,
 246                        &st->als_illum);
 247        if (ret < 0)
 248                return ret;
 249        als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_INTENSITY,
 250                                    st->als_illum.size);
 251        als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
 252                                        st->als_illum.size);
 253
 254        dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
 255                        st->als_illum.report_id);
 256
 257        st->scale_precision = hid_sensor_format_scale(
 258                                HID_USAGE_SENSOR_ALS,
 259                                &st->als_illum,
 260                                &st->scale_pre_decml, &st->scale_post_decml);
 261
 262        /* Set Sensitivity field ids, when there is no individual modifier */
 263        if (st->common_attributes.sensitivity.index < 0) {
 264                sensor_hub_input_get_attribute_info(hsdev,
 265                        HID_FEATURE_REPORT, usage_id,
 266                        HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 267                        HID_USAGE_SENSOR_DATA_LIGHT,
 268                        &st->common_attributes.sensitivity);
 269                dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 270                        st->common_attributes.sensitivity.index,
 271                        st->common_attributes.sensitivity.report_id);
 272        }
 273        return ret;
 274}
 275
 276/* Function to initialize the processing for usage id */
 277static int hid_als_probe(struct platform_device *pdev)
 278{
 279        int ret = 0;
 280        static const char *name = "als";
 281        struct iio_dev *indio_dev;
 282        struct als_state *als_state;
 283        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 284
 285        indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
 286        if (!indio_dev)
 287                return -ENOMEM;
 288        platform_set_drvdata(pdev, indio_dev);
 289
 290        als_state = iio_priv(indio_dev);
 291        als_state->common_attributes.hsdev = hsdev;
 292        als_state->common_attributes.pdev = pdev;
 293
 294        ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
 295                                        &als_state->common_attributes);
 296        if (ret) {
 297                dev_err(&pdev->dev, "failed to setup common attributes\n");
 298                return ret;
 299        }
 300
 301        indio_dev->channels = kmemdup(als_channels,
 302                                      sizeof(als_channels), GFP_KERNEL);
 303        if (!indio_dev->channels) {
 304                dev_err(&pdev->dev, "failed to duplicate channels\n");
 305                return -ENOMEM;
 306        }
 307
 308        ret = als_parse_report(pdev, hsdev,
 309                               (struct iio_chan_spec *)indio_dev->channels,
 310                               HID_USAGE_SENSOR_ALS, als_state);
 311        if (ret) {
 312                dev_err(&pdev->dev, "failed to setup attributes\n");
 313                goto error_free_dev_mem;
 314        }
 315
 316        indio_dev->num_channels =
 317                                ARRAY_SIZE(als_channels);
 318        indio_dev->dev.parent = &pdev->dev;
 319        indio_dev->info = &als_info;
 320        indio_dev->name = name;
 321        indio_dev->modes = INDIO_DIRECT_MODE;
 322
 323        ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 324                NULL, NULL);
 325        if (ret) {
 326                dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 327                goto error_free_dev_mem;
 328        }
 329        atomic_set(&als_state->common_attributes.data_ready, 0);
 330        ret = hid_sensor_setup_trigger(indio_dev, name,
 331                                &als_state->common_attributes);
 332        if (ret < 0) {
 333                dev_err(&pdev->dev, "trigger setup failed\n");
 334                goto error_unreg_buffer_funcs;
 335        }
 336
 337        ret = iio_device_register(indio_dev);
 338        if (ret) {
 339                dev_err(&pdev->dev, "device register failed\n");
 340                goto error_remove_trigger;
 341        }
 342
 343        als_state->callbacks.send_event = als_proc_event;
 344        als_state->callbacks.capture_sample = als_capture_sample;
 345        als_state->callbacks.pdev = pdev;
 346        ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
 347                                        &als_state->callbacks);
 348        if (ret < 0) {
 349                dev_err(&pdev->dev, "callback reg failed\n");
 350                goto error_iio_unreg;
 351        }
 352
 353        return ret;
 354
 355error_iio_unreg:
 356        iio_device_unregister(indio_dev);
 357error_remove_trigger:
 358        hid_sensor_remove_trigger(&als_state->common_attributes);
 359error_unreg_buffer_funcs:
 360        iio_triggered_buffer_cleanup(indio_dev);
 361error_free_dev_mem:
 362        kfree(indio_dev->channels);
 363        return ret;
 364}
 365
 366/* Function to deinitialize the processing for usage id */
 367static int hid_als_remove(struct platform_device *pdev)
 368{
 369        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 370        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 371        struct als_state *als_state = iio_priv(indio_dev);
 372
 373        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
 374        iio_device_unregister(indio_dev);
 375        hid_sensor_remove_trigger(&als_state->common_attributes);
 376        iio_triggered_buffer_cleanup(indio_dev);
 377        kfree(indio_dev->channels);
 378
 379        return 0;
 380}
 381
 382static const struct platform_device_id hid_als_ids[] = {
 383        {
 384                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 385                .name = "HID-SENSOR-200041",
 386        },
 387        { /* sentinel */ }
 388};
 389MODULE_DEVICE_TABLE(platform, hid_als_ids);
 390
 391static struct platform_driver hid_als_platform_driver = {
 392        .id_table = hid_als_ids,
 393        .driver = {
 394                .name   = KBUILD_MODNAME,
 395                .pm     = &hid_sensor_pm_ops,
 396        },
 397        .probe          = hid_als_probe,
 398        .remove         = hid_als_remove,
 399};
 400module_platform_driver(hid_als_platform_driver);
 401
 402MODULE_DESCRIPTION("HID Sensor ALS");
 403MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 404MODULE_LICENSE("GPL");
 405