Quelle  hid-sensor-accel-3d.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * HID Sensors Driver
 * Copyright (c) 2012, Intel Corporation.
 */
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include "../common/hid-sensors/hid-sensor-trigger.h"

enum accel_3d_channel {
 CHANNEL_SCAN_INDEX_X,
 CHANNEL_SCAN_INDEX_Y,
 CHANNEL_SCAN_INDEX_Z,
 ACCEL_3D_CHANNEL_MAX,
};

#define CHANNEL_SCAN_INDEX_TIMESTAMP ACCEL_3D_CHANNEL_MAX
struct accel_3d_state {
 struct hid_sensor_hub_callbacks callbacks;
 struct hid_sensor_common common_attributes;
 struct hid_sensor_hub_attribute_info accel[ACCEL_3D_CHANNEL_MAX];
 /* Ensure timestamp is naturally aligned */
 struct {
  u32 accel_val[3];
  aligned_s64 timestamp;
 } scan;
 int scale_pre_decml;
 int scale_post_decml;
 int scale_precision;
 int value_offset;
 int64_t timestamp;
};

static const u32 accel_3d_addresses[ACCEL_3D_CHANNEL_MAX] = {
 HID_USAGE_SENSOR_ACCEL_X_AXIS,
 HID_USAGE_SENSOR_ACCEL_Y_AXIS,
 HID_USAGE_SENSOR_ACCEL_Z_AXIS
};

static const u32 accel_3d_sensitivity_addresses[] = {
 HID_USAGE_SENSOR_DATA_ACCELERATION,
};

/* Channel definitions */
static const struct iio_chan_spec accel_3d_channels[] = {
 {
  .type = IIO_ACCEL,
  .modified = 1,
  .channel2 = IIO_MOD_X,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_X,
 }, {
  .type = IIO_ACCEL,
  .modified = 1,
  .channel2 = IIO_MOD_Y,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_Y,
 }, {
  .type = IIO_ACCEL,
  .modified = 1,
  .channel2 = IIO_MOD_Z,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_Z,
 },
 IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
};

/* Channel definitions */
static const struct iio_chan_spec gravity_channels[] = {
 {
  .type = IIO_GRAVITY,
  .modified = 1,
  .channel2 = IIO_MOD_X,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_X,
 }, {
  .type = IIO_GRAVITY,
  .modified = 1,
  .channel2 = IIO_MOD_Y,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_Y,
 }, {
  .type = IIO_GRAVITY,
  .modified = 1,
  .channel2 = IIO_MOD_Z,
  .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
  .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
  BIT(IIO_CHAN_INFO_SCALE) |
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |
  BIT(IIO_CHAN_INFO_HYSTERESIS),
  .scan_index = CHANNEL_SCAN_INDEX_Z,
 },
 IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP),
};

/* Adjust channel real bits based on report descriptor */
static void accel_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
      int channel, int size)
{
 channels[channel].scan_type.sign = 's';
 /* Real storage bits will change based on the report desc. */
 channels[channel].scan_type.realbits = size * 8;
 /* Maximum size of a sample to capture is u32 */
 channels[channel].scan_type.storagebits = sizeof(u32) * 8;
}

/* Channel read_raw handler */
static int accel_3d_read_raw(struct iio_dev *indio_dev,
         struct iio_chan_spec const *chan,
         int *val, int *val2,
         long mask)
{
 struct accel_3d_state *accel_state = iio_priv(indio_dev);
 int report_id = -1;
 u32 address;
 int ret_type;
 s32 min;
 struct hid_sensor_hub_device *hsdev =
     accel_state->common_attributes.hsdev;

 *val = 0;
 *val2 = 0;
 switch (mask) {
 case IIO_CHAN_INFO_RAW:
  hid_sensor_power_state(&accel_state->common_attributes, true);
  report_id = accel_state->accel[chan->scan_index].report_id;
  min = accel_state->accel[chan->scan_index].logical_minimum;
  address = accel_3d_addresses[chan->scan_index];
  if (report_id >= 0)
   *val = sensor_hub_input_attr_get_raw_value(
     accel_state->common_attributes.hsdev,
     hsdev->usage, address, report_id,
     SENSOR_HUB_SYNC,
     min < 0);
  else {
   *val = 0;
   hid_sensor_power_state(&accel_state->common_attributes,
       false);
   return -EINVAL;
  }
  hid_sensor_power_state(&accel_state->common_attributes, false);
  ret_type = IIO_VAL_INT;
  break;
 case IIO_CHAN_INFO_SCALE:
  *val = accel_state->scale_pre_decml;
  *val2 = accel_state->scale_post_decml;
  ret_type = accel_state->scale_precision;
  break;
 case IIO_CHAN_INFO_OFFSET:
  *val = accel_state->value_offset;
  ret_type = IIO_VAL_INT;
  break;
 case IIO_CHAN_INFO_SAMP_FREQ:
  ret_type = hid_sensor_read_samp_freq_value(
   &accel_state->common_attributes, val, val2);
  break;
 case IIO_CHAN_INFO_HYSTERESIS:
  ret_type = hid_sensor_read_raw_hyst_value(
   &accel_state->common_attributes, val, val2);
  break;
 default:
  ret_type = -EINVAL;
  break;
 }

 return ret_type;
}

/* Channel write_raw handler */
static int accel_3d_write_raw(struct iio_dev *indio_dev,
          struct iio_chan_spec const *chan,
          int val,
          int val2,
          long mask)
{
 struct accel_3d_state *accel_state = iio_priv(indio_dev);
 int ret = 0;

 switch (mask) {
 case IIO_CHAN_INFO_SAMP_FREQ:
  ret = hid_sensor_write_samp_freq_value(
    &accel_state->common_attributes, val, val2);
  break;
 case IIO_CHAN_INFO_HYSTERESIS:
  ret = hid_sensor_write_raw_hyst_value(
    &accel_state->common_attributes, val, val2);
  break;
 default:
  ret = -EINVAL;
 }

 return ret;
}

static const struct iio_info accel_3d_info = {
 .read_raw = &accel_3d_read_raw,
 .write_raw = &accel_3d_write_raw,
};

/* Function to push data to buffer */
static void hid_sensor_push_data(struct iio_dev *indio_dev, void *data,
     int len, int64_t timestamp)
{
 dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 iio_push_to_buffers_with_ts(indio_dev, data, len, timestamp);
}

/* Callback handler to send event after all samples are received and captured */
static int accel_3d_proc_event(struct hid_sensor_hub_device *hsdev,
    unsigned usage_id,
    void *priv)
{
 struct iio_dev *indio_dev = platform_get_drvdata(priv);
 struct accel_3d_state *accel_state = iio_priv(indio_dev);

 dev_dbg(&indio_dev->dev, "accel_3d_proc_event\n");
 if (atomic_read(&accel_state->common_attributes.data_ready)) {
  if (!accel_state->timestamp)
   accel_state->timestamp = iio_get_time_ns(indio_dev);

  hid_sensor_push_data(indio_dev,
         &accel_state->scan,
         sizeof(accel_state->scan),
         accel_state->timestamp);

  accel_state->timestamp = 0;
 }

 return 0;
}

/* Capture samples in local storage */
static int accel_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
    unsigned usage_id,
    size_t raw_len, char *raw_data,
    void *priv)
{
 struct iio_dev *indio_dev = platform_get_drvdata(priv);
 struct accel_3d_state *accel_state = iio_priv(indio_dev);
 int offset;
 int ret = -EINVAL;

 switch (usage_id) {
 case HID_USAGE_SENSOR_ACCEL_X_AXIS:
 case HID_USAGE_SENSOR_ACCEL_Y_AXIS:
 case HID_USAGE_SENSOR_ACCEL_Z_AXIS:
  offset = usage_id - HID_USAGE_SENSOR_ACCEL_X_AXIS;
  accel_state->scan.accel_val[CHANNEL_SCAN_INDEX_X + offset] =
      *(u32 *)raw_data;
  ret = 0;
 break;
 case HID_USAGE_SENSOR_TIME_TIMESTAMP:
  accel_state->timestamp =
   hid_sensor_convert_timestamp(
     &accel_state->common_attributes,
     *(int64_t *)raw_data);
  ret = 0;
 break;
 default:
  break;
 }

 return ret;
}

/* Parse report which is specific to an usage id*/
static int accel_3d_parse_report(struct platform_device *pdev,
    struct hid_sensor_hub_device *hsdev,
    struct iio_chan_spec *channels,
    unsigned usage_id,
    struct accel_3d_state *st)
{
 int ret;
 int i;

 for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
  ret = sensor_hub_input_get_attribute_info(hsdev,
    HID_INPUT_REPORT,
    usage_id,
    HID_USAGE_SENSOR_ACCEL_X_AXIS + i,
    &st->accel[CHANNEL_SCAN_INDEX_X + i]);
  if (ret < 0)
   break;
  accel_3d_adjust_channel_bit_mask(channels,
    CHANNEL_SCAN_INDEX_X + i,
    st->accel[CHANNEL_SCAN_INDEX_X + i].size);
 }
 dev_dbg(&pdev->dev, "accel_3d %x:%x, %x:%x, %x:%x\n",
   st->accel[0].index,
   st->accel[0].report_id,
   st->accel[1].index, st->accel[1].report_id,
   st->accel[2].index, st->accel[2].report_id);

 st->scale_precision = hid_sensor_format_scale(
    hsdev->usage,
    &st->accel[CHANNEL_SCAN_INDEX_X],
    &st->scale_pre_decml, &st->scale_post_decml);

 return ret;
}

/* Function to initialize the processing for usage id */
static int hid_accel_3d_probe(struct platform_device *pdev)
{
 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 int ret = 0;
 const char *name;
 struct iio_dev *indio_dev;
 struct accel_3d_state *accel_state;
 const struct iio_chan_spec *channel_spec;
 int channel_size;

 indio_dev = devm_iio_device_alloc(&pdev->dev,
       sizeof(struct accel_3d_state));
 if (indio_dev == NULL)
  return -ENOMEM;

 platform_set_drvdata(pdev, indio_dev);

 accel_state = iio_priv(indio_dev);
 accel_state->common_attributes.hsdev = hsdev;
 accel_state->common_attributes.pdev = pdev;

 if (hsdev->usage == HID_USAGE_SENSOR_ACCEL_3D) {
  name = "accel_3d";
  channel_spec = accel_3d_channels;
  channel_size = sizeof(accel_3d_channels);
  indio_dev->num_channels = ARRAY_SIZE(accel_3d_channels);
 } else {
  name = "gravity";
  channel_spec = gravity_channels;
  channel_size = sizeof(gravity_channels);
  indio_dev->num_channels = ARRAY_SIZE(gravity_channels);
 }
 ret = hid_sensor_parse_common_attributes(hsdev,
       hsdev->usage,
       &accel_state->common_attributes,
       accel_3d_sensitivity_addresses,
       ARRAY_SIZE(accel_3d_sensitivity_addresses));
 if (ret) {
  dev_err(&pdev->dev, "failed to setup common attributes\n");
  return ret;
 }
 indio_dev->channels = devm_kmemdup(&pdev->dev, channel_spec,
        channel_size, GFP_KERNEL);

 if (!indio_dev->channels) {
  dev_err(&pdev->dev, "failed to duplicate channels\n");
  return -ENOMEM;
 }
 ret = accel_3d_parse_report(pdev, hsdev,
    (struct iio_chan_spec *)indio_dev->channels,
    hsdev->usage, accel_state);
 if (ret) {
  dev_err(&pdev->dev, "failed to setup attributes\n");
  return ret;
 }

 indio_dev->info = &accel_3d_info;
 indio_dev->name = name;
 indio_dev->modes = INDIO_DIRECT_MODE;

 atomic_set(&accel_state->common_attributes.data_ready, 0);

 ret = hid_sensor_setup_trigger(indio_dev, name,
     &accel_state->common_attributes);
 if (ret < 0) {
  dev_err(&pdev->dev, "trigger setup failed\n");
  return ret;
 }

 ret = iio_device_register(indio_dev);
 if (ret) {
  dev_err(&pdev->dev, "device register failed\n");
  goto error_remove_trigger;
 }

 accel_state->callbacks.send_event = accel_3d_proc_event;
 accel_state->callbacks.capture_sample = accel_3d_capture_sample;
 accel_state->callbacks.pdev = pdev;
 ret = sensor_hub_register_callback(hsdev, hsdev->usage,
     &accel_state->callbacks);
 if (ret < 0) {
  dev_err(&pdev->dev, "callback reg failed\n");
  goto error_iio_unreg;
 }

 return ret;

error_iio_unreg:
 iio_device_unregister(indio_dev);
error_remove_trigger:
 hid_sensor_remove_trigger(indio_dev, &accel_state->common_attributes);
 return ret;
}

/* Function to deinitialize the processing for usage id */
static void hid_accel_3d_remove(struct platform_device *pdev)
{
 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 struct accel_3d_state *accel_state = iio_priv(indio_dev);

 sensor_hub_remove_callback(hsdev, hsdev->usage);
 iio_device_unregister(indio_dev);
 hid_sensor_remove_trigger(indio_dev, &accel_state->common_attributes);
}

static const struct platform_device_id hid_accel_3d_ids[] = {
 {
  /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
  .name = "HID-SENSOR-200073",
 },
 { /* gravity sensor */
  .name = "HID-SENSOR-20007b",
 },
 { }
};
MODULE_DEVICE_TABLE(platform, hid_accel_3d_ids);

static struct platform_driver hid_accel_3d_platform_driver = {
 .id_table = hid_accel_3d_ids,
 .driver = {
  .name = KBUILD_MODNAME,
  .pm = &hid_sensor_pm_ops,
 },
 .probe  = hid_accel_3d_probe,
 .remove  = hid_accel_3d_remove,
};
module_platform_driver(hid_accel_3d_platform_driver);

MODULE_DESCRIPTION("HID Sensor Accel 3D");
MODULE_AUTHOR("Srinivas Pandruvada ");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID");