linux/drivers/iio/orientation/hid-sensor-rotation.c
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   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
  15#include <linux/device.h>
  16#include <linux/platform_device.h>
  17#include <linux/module.h>
  18#include <linux/interrupt.h>
  19#include <linux/irq.h>
  20#include <linux/slab.h>
  21#include <linux/hid-sensor-hub.h>
  22#include <linux/iio/iio.h>
  23#include <linux/iio/sysfs.h>
  24#include <linux/iio/buffer.h>
  25#include <linux/iio/trigger_consumer.h>
  26#include <linux/iio/triggered_buffer.h>
  27#include "../common/hid-sensors/hid-sensor-trigger.h"
  28
  29struct dev_rot_state {
  30        struct hid_sensor_hub_callbacks callbacks;
  31        struct hid_sensor_common common_attributes;
  32        struct hid_sensor_hub_attribute_info quaternion;
  33        u32 sampled_vals[4];
  34};
  35
  36/* Channel definitions */
  37static const struct iio_chan_spec dev_rot_channels[] = {
  38        {
  39                .type = IIO_ROT,
  40                .modified = 1,
  41                .channel2 = IIO_MOD_QUATERNION,
  42                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  43                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  44                                        BIT(IIO_CHAN_INFO_HYSTERESIS)
  45        }
  46};
  47
  48/* Adjust channel real bits based on report descriptor */
  49static void dev_rot_adjust_channel_bit_mask(struct iio_chan_spec *chan,
  50                                                int size)
  51{
  52        chan->scan_type.sign = 's';
  53        /* Real storage bits will change based on the report desc. */
  54        chan->scan_type.realbits = size * 8;
  55        /* Maximum size of a sample to capture is u32 */
  56        chan->scan_type.storagebits = sizeof(u32) * 8;
  57        chan->scan_type.repeat = 4;
  58}
  59
  60/* Channel read_raw handler */
  61static int dev_rot_read_raw(struct iio_dev *indio_dev,
  62                                struct iio_chan_spec const *chan,
  63                                int size, int *vals, int *val_len,
  64                                long mask)
  65{
  66        struct dev_rot_state *rot_state = iio_priv(indio_dev);
  67        int ret_type;
  68        int i;
  69
  70        vals[0] = 0;
  71        vals[1] = 0;
  72
  73        switch (mask) {
  74        case IIO_CHAN_INFO_RAW:
  75                if (size >= 4) {
  76                        for (i = 0; i < 4; ++i)
  77                                vals[i] = rot_state->sampled_vals[i];
  78                        ret_type = IIO_VAL_INT_MULTIPLE;
  79                        *val_len =  4;
  80                } else
  81                        ret_type = -EINVAL;
  82                break;
  83        case IIO_CHAN_INFO_SAMP_FREQ:
  84                ret_type = hid_sensor_read_samp_freq_value(
  85                        &rot_state->common_attributes, &vals[0], &vals[1]);
  86                break;
  87        case IIO_CHAN_INFO_HYSTERESIS:
  88                ret_type = hid_sensor_read_raw_hyst_value(
  89                        &rot_state->common_attributes, &vals[0], &vals[1]);
  90                break;
  91        default:
  92                ret_type = -EINVAL;
  93                break;
  94        }
  95
  96        return ret_type;
  97}
  98
  99/* Channel write_raw handler */
 100static int dev_rot_write_raw(struct iio_dev *indio_dev,
 101                               struct iio_chan_spec const *chan,
 102                               int val,
 103                               int val2,
 104                               long mask)
 105{
 106        struct dev_rot_state *rot_state = iio_priv(indio_dev);
 107        int ret;
 108
 109        switch (mask) {
 110        case IIO_CHAN_INFO_SAMP_FREQ:
 111                ret = hid_sensor_write_samp_freq_value(
 112                                &rot_state->common_attributes, val, val2);
 113                break;
 114        case IIO_CHAN_INFO_HYSTERESIS:
 115                ret = hid_sensor_write_raw_hyst_value(
 116                                &rot_state->common_attributes, val, val2);
 117                break;
 118        default:
 119                ret = -EINVAL;
 120        }
 121
 122        return ret;
 123}
 124
 125static const struct iio_info dev_rot_info = {
 126        .driver_module = THIS_MODULE,
 127        .read_raw_multi = &dev_rot_read_raw,
 128        .write_raw = &dev_rot_write_raw,
 129};
 130
 131/* Function to push data to buffer */
 132static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
 133{
 134        dev_dbg(&indio_dev->dev, "hid_sensor_push_data >>\n");
 135        iio_push_to_buffers(indio_dev, (u8 *)data);
 136        dev_dbg(&indio_dev->dev, "hid_sensor_push_data <<\n");
 137
 138}
 139
 140/* Callback handler to send event after all samples are received and captured */
 141static int dev_rot_proc_event(struct hid_sensor_hub_device *hsdev,
 142                                unsigned usage_id,
 143                                void *priv)
 144{
 145        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 146        struct dev_rot_state *rot_state = iio_priv(indio_dev);
 147
 148        dev_dbg(&indio_dev->dev, "dev_rot_proc_event\n");
 149        if (atomic_read(&rot_state->common_attributes.data_ready))
 150                hid_sensor_push_data(indio_dev,
 151                                (u8 *)rot_state->sampled_vals,
 152                                sizeof(rot_state->sampled_vals));
 153
 154        return 0;
 155}
 156
 157/* Capture samples in local storage */
 158static int dev_rot_capture_sample(struct hid_sensor_hub_device *hsdev,
 159                                unsigned usage_id,
 160                                size_t raw_len, char *raw_data,
 161                                void *priv)
 162{
 163        struct iio_dev *indio_dev = platform_get_drvdata(priv);
 164        struct dev_rot_state *rot_state = iio_priv(indio_dev);
 165
 166        if (usage_id == HID_USAGE_SENSOR_ORIENT_QUATERNION) {
 167                memcpy(rot_state->sampled_vals, raw_data,
 168                                        sizeof(rot_state->sampled_vals));
 169                dev_dbg(&indio_dev->dev, "Recd Quat len:%zu::%zu\n", raw_len,
 170                                        sizeof(rot_state->sampled_vals));
 171        }
 172
 173        return 0;
 174}
 175
 176/* Parse report which is specific to an usage id*/
 177static int dev_rot_parse_report(struct platform_device *pdev,
 178                                struct hid_sensor_hub_device *hsdev,
 179                                struct iio_chan_spec *channels,
 180                                unsigned usage_id,
 181                                struct dev_rot_state *st)
 182{
 183        int ret;
 184
 185        ret = sensor_hub_input_get_attribute_info(hsdev,
 186                                HID_INPUT_REPORT,
 187                                usage_id,
 188                                HID_USAGE_SENSOR_ORIENT_QUATERNION,
 189                                &st->quaternion);
 190        if (ret)
 191                return ret;
 192
 193        dev_rot_adjust_channel_bit_mask(&channels[0],
 194                st->quaternion.size / 4);
 195
 196        dev_dbg(&pdev->dev, "dev_rot %x:%x\n", st->quaternion.index,
 197                st->quaternion.report_id);
 198
 199        dev_dbg(&pdev->dev, "dev_rot: attrib size %d\n",
 200                                st->quaternion.size);
 201
 202        /* Set Sensitivity field ids, when there is no individual modifier */
 203        if (st->common_attributes.sensitivity.index < 0) {
 204                sensor_hub_input_get_attribute_info(hsdev,
 205                        HID_FEATURE_REPORT, usage_id,
 206                        HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 207                        HID_USAGE_SENSOR_DATA_ORIENTATION,
 208                        &st->common_attributes.sensitivity);
 209                dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
 210                        st->common_attributes.sensitivity.index,
 211                        st->common_attributes.sensitivity.report_id);
 212        }
 213
 214        return 0;
 215}
 216
 217/* Function to initialize the processing for usage id */
 218static int hid_dev_rot_probe(struct platform_device *pdev)
 219{
 220        int ret;
 221        static char *name = "dev_rotation";
 222        struct iio_dev *indio_dev;
 223        struct dev_rot_state *rot_state;
 224        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 225
 226        indio_dev = devm_iio_device_alloc(&pdev->dev,
 227                                          sizeof(struct dev_rot_state));
 228        if (indio_dev == NULL)
 229                return -ENOMEM;
 230
 231        platform_set_drvdata(pdev, indio_dev);
 232
 233        rot_state = iio_priv(indio_dev);
 234        rot_state->common_attributes.hsdev = hsdev;
 235        rot_state->common_attributes.pdev = pdev;
 236
 237        ret = hid_sensor_parse_common_attributes(hsdev,
 238                                HID_USAGE_SENSOR_DEVICE_ORIENTATION,
 239                                &rot_state->common_attributes);
 240        if (ret) {
 241                dev_err(&pdev->dev, "failed to setup common attributes\n");
 242                return ret;
 243        }
 244
 245        indio_dev->channels = devm_kmemdup(&pdev->dev, dev_rot_channels,
 246                                           sizeof(dev_rot_channels),
 247                                           GFP_KERNEL);
 248        if (!indio_dev->channels) {
 249                dev_err(&pdev->dev, "failed to duplicate channels\n");
 250                return -ENOMEM;
 251        }
 252
 253        ret = dev_rot_parse_report(pdev, hsdev,
 254                                   (struct iio_chan_spec *)indio_dev->channels,
 255                                   HID_USAGE_SENSOR_DEVICE_ORIENTATION,
 256                                   rot_state);
 257        if (ret) {
 258                dev_err(&pdev->dev, "failed to setup attributes\n");
 259                return ret;
 260        }
 261
 262        indio_dev->num_channels = ARRAY_SIZE(dev_rot_channels);
 263        indio_dev->dev.parent = &pdev->dev;
 264        indio_dev->info = &dev_rot_info;
 265        indio_dev->name = name;
 266        indio_dev->modes = INDIO_DIRECT_MODE;
 267
 268        ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 269                NULL, NULL);
 270        if (ret) {
 271                dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 272                return ret;
 273        }
 274        atomic_set(&rot_state->common_attributes.data_ready, 0);
 275        ret = hid_sensor_setup_trigger(indio_dev, name,
 276                                        &rot_state->common_attributes);
 277        if (ret) {
 278                dev_err(&pdev->dev, "trigger setup failed\n");
 279                goto error_unreg_buffer_funcs;
 280        }
 281
 282        ret = iio_device_register(indio_dev);
 283        if (ret) {
 284                dev_err(&pdev->dev, "device register failed\n");
 285                goto error_remove_trigger;
 286        }
 287
 288        rot_state->callbacks.send_event = dev_rot_proc_event;
 289        rot_state->callbacks.capture_sample = dev_rot_capture_sample;
 290        rot_state->callbacks.pdev = pdev;
 291        ret = sensor_hub_register_callback(hsdev,
 292                                        HID_USAGE_SENSOR_DEVICE_ORIENTATION,
 293                                        &rot_state->callbacks);
 294        if (ret) {
 295                dev_err(&pdev->dev, "callback reg failed\n");
 296                goto error_iio_unreg;
 297        }
 298
 299        return 0;
 300
 301error_iio_unreg:
 302        iio_device_unregister(indio_dev);
 303error_remove_trigger:
 304        hid_sensor_remove_trigger(&rot_state->common_attributes);
 305error_unreg_buffer_funcs:
 306        iio_triggered_buffer_cleanup(indio_dev);
 307        return ret;
 308}
 309
 310/* Function to deinitialize the processing for usage id */
 311static int hid_dev_rot_remove(struct platform_device *pdev)
 312{
 313        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 314        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 315        struct dev_rot_state *rot_state = iio_priv(indio_dev);
 316
 317        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_DEVICE_ORIENTATION);
 318        iio_device_unregister(indio_dev);
 319        hid_sensor_remove_trigger(&rot_state->common_attributes);
 320        iio_triggered_buffer_cleanup(indio_dev);
 321
 322        return 0;
 323}
 324
 325static const struct platform_device_id hid_dev_rot_ids[] = {
 326        {
 327                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 328                .name = "HID-SENSOR-20008a",
 329        },
 330        { /* sentinel */ }
 331};
 332MODULE_DEVICE_TABLE(platform, hid_dev_rot_ids);
 333
 334static struct platform_driver hid_dev_rot_platform_driver = {
 335        .id_table = hid_dev_rot_ids,
 336        .driver = {
 337                .name   = KBUILD_MODNAME,
 338        },
 339        .probe          = hid_dev_rot_probe,
 340        .remove         = hid_dev_rot_remove,
 341};
 342module_platform_driver(hid_dev_rot_platform_driver);
 343
 344MODULE_DESCRIPTION("HID Sensor Device Rotation");
 345MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 346MODULE_LICENSE("GPL");
 347