Quelle  hid-sensor-magn-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/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include "../common/hid-sensors/hid-sensor-trigger.h"

enum magn_3d_channel {
 CHANNEL_SCAN_INDEX_X,
 CHANNEL_SCAN_INDEX_Y,
 CHANNEL_SCAN_INDEX_Z,
 CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP,
 CHANNEL_SCAN_INDEX_NORTH_TRUE_TILT_COMP,
 CHANNEL_SCAN_INDEX_NORTH_MAGN,
 CHANNEL_SCAN_INDEX_NORTH_TRUE,
 CHANNEL_SCAN_INDEX_TIMESTAMP,
 MAGN_3D_CHANNEL_MAX,
};

struct common_attributes {
 int scale_pre_decml;
 int scale_post_decml;
 int scale_precision;
 int value_offset;
};

struct magn_3d_state {
 struct hid_sensor_hub_callbacks callbacks;
 struct hid_sensor_common magn_flux_attributes;
 struct hid_sensor_common rot_attributes;
 struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];

 /* dynamically sized array to hold sensor values */
 u32 *iio_vals;
 /* array of pointers to sensor value */
 u32 *magn_val_addr[MAGN_3D_CHANNEL_MAX];

 struct common_attributes magn_flux_attr;
 struct common_attributes rot_attr;
 s64 timestamp;
};

static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
 HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
 HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
 HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS,
 HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH,
 HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH,
 HID_USAGE_SENSOR_ORIENT_MAGN_NORTH,
 HID_USAGE_SENSOR_ORIENT_TRUE_NORTH,
 HID_USAGE_SENSOR_TIME_TIMESTAMP,
};

static const u32 magn_3d_sensitivity_addresses[] = {
 HID_USAGE_SENSOR_DATA_ORIENTATION,
 HID_USAGE_SENSOR_ORIENT_MAGN_FLUX,
};

/* Channel definitions */
static const struct iio_chan_spec magn_3d_channels[] = {
 {
  .type = IIO_MAGN,
  .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),
 }, {
  .type = IIO_MAGN,
  .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),
 }, {
  .type = IIO_MAGN,
  .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),
 }, {
  .type = IIO_ROT,
  .modified = 1,
  .channel2 = IIO_MOD_NORTH_MAGN_TILT_COMP,
  .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),
 }, {
  .type = IIO_ROT,
  .modified = 1,
  .channel2 = IIO_MOD_NORTH_TRUE_TILT_COMP,
  .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),
 }, {
  .type = IIO_ROT,
  .modified = 1,
  .channel2 = IIO_MOD_NORTH_MAGN,
  .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),
 }, {
  .type = IIO_ROT,
  .modified = 1,
  .channel2 = IIO_MOD_NORTH_TRUE,
  .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),
 },
 IIO_CHAN_SOFT_TIMESTAMP(7)
};

/* Adjust channel real bits based on report descriptor */
static void magn_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 magn_3d_read_raw(struct iio_dev *indio_dev,
         struct iio_chan_spec const *chan,
         int *val, int *val2,
         long mask)
{
 struct magn_3d_state *magn_state = iio_priv(indio_dev);
 int report_id = -1;
 u32 address;
 int ret_type;
 s32 min;

 *val = 0;
 *val2 = 0;
 switch (mask) {
 case IIO_CHAN_INFO_RAW:
  hid_sensor_power_state(&magn_state->magn_flux_attributes, true);
  report_id = magn_state->magn[chan->address].report_id;
  min = magn_state->magn[chan->address].logical_minimum;
  address = magn_3d_addresses[chan->address];
  if (report_id >= 0)
   *val = sensor_hub_input_attr_get_raw_value(
    magn_state->magn_flux_attributes.hsdev,
    HID_USAGE_SENSOR_COMPASS_3D, address,
    report_id,
    SENSOR_HUB_SYNC,
    min < 0);
  else {
   *val = 0;
   hid_sensor_power_state(
    &magn_state->magn_flux_attributes,
    false);
   return -EINVAL;
  }
  hid_sensor_power_state(&magn_state->magn_flux_attributes,
     false);
  ret_type = IIO_VAL_INT;
  break;
 case IIO_CHAN_INFO_SCALE:
  switch (chan->type) {
  case IIO_MAGN:
   *val = magn_state->magn_flux_attr.scale_pre_decml;
   *val2 = magn_state->magn_flux_attr.scale_post_decml;
   ret_type = magn_state->magn_flux_attr.scale_precision;
   break;
  case IIO_ROT:
   *val = magn_state->rot_attr.scale_pre_decml;
   *val2 = magn_state->rot_attr.scale_post_decml;
   ret_type = magn_state->rot_attr.scale_precision;
   break;
  default:
   ret_type = -EINVAL;
  }
  break;
 case IIO_CHAN_INFO_OFFSET:
  switch (chan->type) {
  case IIO_MAGN:
   *val = magn_state->magn_flux_attr.value_offset;
   ret_type = IIO_VAL_INT;
   break;
  case IIO_ROT:
   *val = magn_state->rot_attr.value_offset;
   ret_type = IIO_VAL_INT;
   break;
  default:
   ret_type = -EINVAL;
  }
  break;
 case IIO_CHAN_INFO_SAMP_FREQ:
  ret_type = hid_sensor_read_samp_freq_value(
   &magn_state->magn_flux_attributes, val, val2);
  break;
 case IIO_CHAN_INFO_HYSTERESIS:
  switch (chan->type) {
  case IIO_MAGN:
   ret_type = hid_sensor_read_raw_hyst_value(
    &magn_state->magn_flux_attributes, val, val2);
   break;
  case IIO_ROT:
   ret_type = hid_sensor_read_raw_hyst_value(
    &magn_state->rot_attributes, val, val2);
   break;
  default:
   ret_type = -EINVAL;
  }
  break;
 default:
  ret_type = -EINVAL;
  break;
 }

 return ret_type;
}

/* Channel write_raw handler */
static int magn_3d_write_raw(struct iio_dev *indio_dev,
          struct iio_chan_spec const *chan,
          int val,
          int val2,
          long mask)
{
 struct magn_3d_state *magn_state = iio_priv(indio_dev);
 int ret = 0;

 switch (mask) {
 case IIO_CHAN_INFO_SAMP_FREQ:
  ret = hid_sensor_write_samp_freq_value(
    &magn_state->magn_flux_attributes, val, val2);
  break;
 case IIO_CHAN_INFO_HYSTERESIS:
  switch (chan->type) {
  case IIO_MAGN:
   ret = hid_sensor_write_raw_hyst_value(
    &magn_state->magn_flux_attributes, val, val2);
   break;
  case IIO_ROT:
   ret = hid_sensor_write_raw_hyst_value(
    &magn_state->rot_attributes, val, val2);
   break;
  default:
   ret = -EINVAL;
  }
  break;
 default:
  ret = -EINVAL;
 }

 return ret;
}

static const struct iio_info magn_3d_info = {
 .read_raw = &magn_3d_read_raw,
 .write_raw = &magn_3d_write_raw,
};

/* Callback handler to send event after all samples are received and captured */
static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
    unsigned usage_id,
    void *priv)
{
 struct iio_dev *indio_dev = platform_get_drvdata(priv);
 struct magn_3d_state *magn_state = iio_priv(indio_dev);

 dev_dbg(&indio_dev->dev, "magn_3d_proc_event\n");
 if (atomic_read(&magn_state->magn_flux_attributes.data_ready)) {
  if (!magn_state->timestamp)
   magn_state->timestamp = iio_get_time_ns(indio_dev);

  iio_push_to_buffers_with_timestamp(indio_dev,
         magn_state->iio_vals,
         magn_state->timestamp);
  magn_state->timestamp = 0;
 }

 return 0;
}

/* Capture samples in local storage */
static int magn_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 magn_3d_state *magn_state = iio_priv(indio_dev);
 int offset;
 int ret = 0;
 u32 *iio_val = NULL;

 switch (usage_id) {
 case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
 case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
 case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
  offset = (usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS)
    + CHANNEL_SCAN_INDEX_X;
 break;
 case HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH:
 case HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH:
 case HID_USAGE_SENSOR_ORIENT_MAGN_NORTH:
 case HID_USAGE_SENSOR_ORIENT_TRUE_NORTH:
  offset = (usage_id - HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH)
    + CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP;
 break;
 case HID_USAGE_SENSOR_TIME_TIMESTAMP:
  magn_state->timestamp =
   hid_sensor_convert_timestamp(&magn_state->magn_flux_attributes,
           *(s64 *)raw_data);
  return ret;
 default:
  return -EINVAL;
 }

 iio_val = magn_state->magn_val_addr[offset];

 if (iio_val != NULL)
  *iio_val = *((u32 *)raw_data);
 else
  ret = -EINVAL;

 return ret;
}

/* Parse report which is specific to an usage id*/
static int magn_3d_parse_report(struct platform_device *pdev,
    struct hid_sensor_hub_device *hsdev,
    struct iio_chan_spec **channels,
    int *chan_count,
    unsigned usage_id,
    struct magn_3d_state *st)
{
 int i;
 int attr_count = 0;
 struct iio_chan_spec *_channels;

 /* Scan for each usage attribute supported */
 for (i = 0; i < MAGN_3D_CHANNEL_MAX; i++) {
  int status;
  u32 address = magn_3d_addresses[i];

  /* Check if usage attribute exists in the sensor hub device */
  status = sensor_hub_input_get_attribute_info(hsdev,
   HID_INPUT_REPORT,
   usage_id,
   address,
   &(st->magn[i]));
  if (!status)
   attr_count++;
 }

 if (attr_count <= 0) {
  dev_err(&pdev->dev,
   "failed to find any supported usage attributes in report\n");
  return  -EINVAL;
 }

 dev_dbg(&pdev->dev, "magn_3d Found %d usage attributes\n",
   attr_count);
 dev_dbg(&pdev->dev, "magn_3d X: %x:%x Y: %x:%x Z: %x:%x\n",
   st->magn[0].index,
   st->magn[0].report_id,
   st->magn[1].index, st->magn[1].report_id,
   st->magn[2].index, st->magn[2].report_id);

 /* Setup IIO channel array */
 _channels = devm_kcalloc(&pdev->dev, attr_count,
    sizeof(struct iio_chan_spec),
    GFP_KERNEL);
 if (!_channels) {
  dev_err(&pdev->dev,
   "failed to allocate space for iio channels\n");
  return -ENOMEM;
 }

 /* attr_count include timestamp channel, and the iio_vals should be aligned to 8byte */
 st->iio_vals = devm_kcalloc(&pdev->dev,
        ((attr_count + 1) % 2 + (attr_count + 1) / 2) * 2,
        sizeof(u32), GFP_KERNEL);
 if (!st->iio_vals) {
  dev_err(&pdev->dev,
   "failed to allocate space for iio values array\n");
  return -ENOMEM;
 }

 for (i = 0, *chan_count = 0;
 i < MAGN_3D_CHANNEL_MAX && *chan_count < attr_count;
 i++){
  if (st->magn[i].index >= 0) {
   /* Setup IIO channel struct */
   (_channels[*chan_count]) = magn_3d_channels[i];
   (_channels[*chan_count]).scan_index = *chan_count;
   (_channels[*chan_count]).address = i;

   if (i != CHANNEL_SCAN_INDEX_TIMESTAMP) {
    /* Set magn_val_addr to iio value address */
    st->magn_val_addr[i] = &st->iio_vals[*chan_count];
    magn_3d_adjust_channel_bit_mask(_channels,
        *chan_count,
        st->magn[i].size);
   }
   (*chan_count)++;
  }
 }

 if (*chan_count <= 0) {
  dev_err(&pdev->dev,
   "failed to find any magnetic channels setup\n");
  return -EINVAL;
 }

 *channels = _channels;

 dev_dbg(&pdev->dev, "magn_3d Setup %d IIO channels\n",
   *chan_count);

 st->magn_flux_attr.scale_precision = hid_sensor_format_scale(
    HID_USAGE_SENSOR_COMPASS_3D,
    &st->magn[CHANNEL_SCAN_INDEX_X],
    &st->magn_flux_attr.scale_pre_decml,
    &st->magn_flux_attr.scale_post_decml);
 st->rot_attr.scale_precision
  = hid_sensor_format_scale(
   HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH,
   &st->magn[CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP],
   &st->rot_attr.scale_pre_decml,
   &st->rot_attr.scale_post_decml);

 if (st->rot_attributes.sensitivity.index < 0) {
  sensor_hub_input_get_attribute_info(hsdev,
   HID_FEATURE_REPORT, usage_id,
   HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
   HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH,
   &st->rot_attributes.sensitivity);
  dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
   st->rot_attributes.sensitivity.index,
   st->rot_attributes.sensitivity.report_id);
 }

 return 0;
}

/* Function to initialize the processing for usage id */
static int hid_magn_3d_probe(struct platform_device *pdev)
{
 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 int ret = 0;
 static char *name = "magn_3d";
 struct iio_dev *indio_dev;
 struct magn_3d_state *magn_state;
 struct iio_chan_spec *channels;
 int chan_count = 0;

 indio_dev = devm_iio_device_alloc(&pdev->dev,
       sizeof(struct magn_3d_state));
 if (indio_dev == NULL)
  return -ENOMEM;

 platform_set_drvdata(pdev, indio_dev);

 magn_state = iio_priv(indio_dev);
 magn_state->magn_flux_attributes.hsdev = hsdev;
 magn_state->magn_flux_attributes.pdev = pdev;

 ret = hid_sensor_parse_common_attributes(hsdev,
    HID_USAGE_SENSOR_COMPASS_3D,
    &magn_state->magn_flux_attributes,
    magn_3d_sensitivity_addresses,
    ARRAY_SIZE(magn_3d_sensitivity_addresses));
 if (ret) {
  dev_err(&pdev->dev, "failed to setup common attributes\n");
  return ret;
 }
 magn_state->rot_attributes = magn_state->magn_flux_attributes;
 /* sensitivity of rot_attribute is not the same as magn_flux_attributes */
 magn_state->rot_attributes.sensitivity.index = -1;

 ret = magn_3d_parse_report(pdev, hsdev,
    &channels, &chan_count,
    HID_USAGE_SENSOR_COMPASS_3D, magn_state);
 if (ret) {
  dev_err(&pdev->dev, "failed to parse report\n");
  return ret;
 }

 indio_dev->channels = channels;
 indio_dev->num_channels = chan_count;
 indio_dev->info = &magn_3d_info;
 indio_dev->name = name;
 indio_dev->modes = INDIO_DIRECT_MODE;

 atomic_set(&magn_state->magn_flux_attributes.data_ready, 0);

 ret = hid_sensor_setup_trigger(indio_dev, name,
     &magn_state->magn_flux_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;
 }

 magn_state->callbacks.send_event = magn_3d_proc_event;
 magn_state->callbacks.capture_sample = magn_3d_capture_sample;
 magn_state->callbacks.pdev = pdev;
 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D,
     &magn_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, &magn_state->magn_flux_attributes);
 return ret;
}

/* Function to deinitialize the processing for usage id */
static void hid_magn_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 magn_3d_state *magn_state = iio_priv(indio_dev);

 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_COMPASS_3D);
 iio_device_unregister(indio_dev);
 hid_sensor_remove_trigger(indio_dev, &magn_state->magn_flux_attributes);
}

static const struct platform_device_id hid_magn_3d_ids[] = {
 {
  /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
  .name = "HID-SENSOR-200083",
 },
 { }
};
MODULE_DEVICE_TABLE(platform, hid_magn_3d_ids);

static struct platform_driver hid_magn_3d_platform_driver = {
 .id_table = hid_magn_3d_ids,
 .driver = {
  .name = KBUILD_MODNAME,
  .pm = &hid_sensor_pm_ops,
 },
 .probe  = hid_magn_3d_probe,
 .remove  = hid_magn_3d_remove,
};
module_platform_driver(hid_magn_3d_platform_driver);

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