Quelle  hid-sensor-prox.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * HID Sensors Driver
 * Copyright (c) 2014, 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"

static const u32 prox_usage_ids[] = {
 HID_USAGE_SENSOR_HUMAN_PRESENCE,
 HID_USAGE_SENSOR_HUMAN_PROXIMITY,
 HID_USAGE_SENSOR_HUMAN_ATTENTION,
};

#define MAX_CHANNELS ARRAY_SIZE(prox_usage_ids)

enum {
 HID_HUMAN_PRESENCE,
 HID_HUMAN_PROXIMITY,
 HID_HUMAN_ATTENTION,
};

struct prox_state {
 struct hid_sensor_hub_callbacks callbacks;
 struct hid_sensor_common common_attributes;
 struct hid_sensor_hub_attribute_info prox_attr[MAX_CHANNELS];
 struct iio_chan_spec channels[MAX_CHANNELS];
 u32 channel2usage[MAX_CHANNELS];
 u32 human_presence[MAX_CHANNELS];
 int scale_pre_decml[MAX_CHANNELS];
 int scale_post_decml[MAX_CHANNELS];
 int scale_precision[MAX_CHANNELS];
 unsigned long scan_mask[2]; /* One entry plus one terminator. */
 int num_channels;
};

static const u32 prox_sensitivity_addresses[] = {
 HID_USAGE_SENSOR_HUMAN_PRESENCE,
 HID_USAGE_SENSOR_DATA_PRESENCE,
};

#define PROX_CHANNEL(_is_proximity, _channel) \
 {\
  .type = _is_proximity ? IIO_PROXIMITY : IIO_ATTENTION,\
  .info_mask_separate = \
  (_is_proximity ? BIT(IIO_CHAN_INFO_RAW) :\
    BIT(IIO_CHAN_INFO_PROCESSED)) |\
  BIT(IIO_CHAN_INFO_OFFSET) |\
  BIT(IIO_CHAN_INFO_SCALE) |\
  BIT(IIO_CHAN_INFO_SAMP_FREQ) |\
  BIT(IIO_CHAN_INFO_HYSTERESIS),\
  .indexed = _is_proximity,\
  .channel = _channel,\
 }

/* Channel definitions (same order as prox_usage_ids) */
static const struct iio_chan_spec prox_channels[] = {
 PROX_CHANNEL(true, HID_HUMAN_PRESENCE),
 PROX_CHANNEL(true, HID_HUMAN_PROXIMITY),
 PROX_CHANNEL(false, 0),
};

/* Adjust channel real bits based on report descriptor */
static void prox_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 prox_read_raw(struct iio_dev *indio_dev,
         struct iio_chan_spec const *chan,
         int *val, int *val2,
         long mask)
{
 struct prox_state *prox_state = iio_priv(indio_dev);
 struct hid_sensor_hub_device *hsdev;
 int report_id;
 u32 address;
 int ret_type;
 s32 min;

 *val = 0;
 *val2 = 0;
 switch (mask) {
 case IIO_CHAN_INFO_RAW:
 case IIO_CHAN_INFO_PROCESSED:
  if (chan->scan_index >= prox_state->num_channels)
   return -EINVAL;
  address = prox_state->channel2usage[chan->scan_index];
  report_id = prox_state->prox_attr[chan->scan_index].report_id;
  hsdev = prox_state->common_attributes.hsdev;
  min = prox_state->prox_attr[chan->scan_index].logical_minimum;
  hid_sensor_power_state(&prox_state->common_attributes, true);
  *val = sensor_hub_input_attr_get_raw_value(hsdev,
          hsdev->usage,
          address,
          report_id,
          SENSOR_HUB_SYNC,
          min < 0);
  if (prox_state->channel2usage[chan->scan_index] ==
      HID_USAGE_SENSOR_HUMAN_ATTENTION)
   *val *= 100;
  hid_sensor_power_state(&prox_state->common_attributes, false);
  ret_type = IIO_VAL_INT;
  break;
 case IIO_CHAN_INFO_SCALE:
  if (chan->scan_index >= prox_state->num_channels)
   return -EINVAL;

  *val = prox_state->scale_pre_decml[chan->scan_index];
  *val2 = prox_state->scale_post_decml[chan->scan_index];
  ret_type = prox_state->scale_precision[chan->scan_index];
  break;
 case IIO_CHAN_INFO_OFFSET:
  *val = 0;
  ret_type = IIO_VAL_INT;
  break;
 case IIO_CHAN_INFO_SAMP_FREQ:
  ret_type = hid_sensor_read_samp_freq_value(
    &prox_state->common_attributes, val, val2);
  break;
 case IIO_CHAN_INFO_HYSTERESIS:
  ret_type = hid_sensor_read_raw_hyst_value(
    &prox_state->common_attributes, val, val2);
  break;
 default:
  ret_type = -EINVAL;
  break;
 }

 return ret_type;
}

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

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

 return ret;
}

static const struct iio_info prox_info = {
 .read_raw = &prox_read_raw,
 .write_raw = &prox_write_raw,
};

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

 dev_dbg(&indio_dev->dev, "prox_proc_event\n");
 if (atomic_read(&prox_state->common_attributes.data_ready)) {
  dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
  iio_push_to_buffers(indio_dev, &prox_state->human_presence);
 }

 return 0;
}

/* Capture samples in local storage */
static int prox_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 prox_state *prox_state = iio_priv(indio_dev);
 int multiplier = 1;
 int chan;

 for (chan = 0; chan < prox_state->num_channels; chan++)
  if (prox_state->channel2usage[chan] == usage_id)
   break;
 if (chan == prox_state->num_channels)
  return -EINVAL;

 if (usage_id == HID_USAGE_SENSOR_HUMAN_ATTENTION)
  multiplier = 100;

 switch (raw_len) {
 case 1:
  prox_state->human_presence[chan] = *(u8 *)raw_data * multiplier;
  return 0;
 case 2:
  prox_state->human_presence[chan] = *(u16 *)raw_data * multiplier;
  return 0;
 case 4:
  prox_state->human_presence[chan] = *(u32 *)raw_data * multiplier;
  return 0;
 }

 return -EINVAL;
}

/* Parse report which is specific to an usage id*/
static int prox_parse_report(struct platform_device *pdev,
    struct hid_sensor_hub_device *hsdev,
    struct prox_state *st)
{
 struct iio_chan_spec *channels = st->channels;
 int index = 0;
 int ret;
 int i;

 for (i = 0; i < MAX_CHANNELS; i++) {
  u32 usage_id = prox_usage_ids[i];

  ret = sensor_hub_input_get_attribute_info(hsdev,
         HID_INPUT_REPORT,
         hsdev->usage,
         usage_id,
         &st->prox_attr[index]);
  if (ret < 0)
   continue;
  st->channel2usage[index] = usage_id;
  st->scan_mask[0] |= BIT(index);
  channels[index] = prox_channels[i];
  channels[index].scan_index = index;
  prox_adjust_channel_bit_mask(channels, index,
          st->prox_attr[index].size);
  dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr[index].index,
   st->prox_attr[index].report_id);
  st->scale_precision[index] =
   hid_sensor_format_scale(usage_id, &st->prox_attr[index],
      &st->scale_pre_decml[index],
      &st->scale_post_decml[index]);
  index++;
 }

 if (!index)
  return ret;

 st->num_channels = index;

 return 0;
}

/* Function to initialize the processing for usage id */
static int hid_prox_probe(struct platform_device *pdev)
{
 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 int ret = 0;
 static const char *name = "prox";
 struct iio_dev *indio_dev;
 struct prox_state *prox_state;

 indio_dev = devm_iio_device_alloc(&pdev->dev,
    sizeof(struct prox_state));
 if (!indio_dev)
  return -ENOMEM;
 platform_set_drvdata(pdev, indio_dev);

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

 ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
     &prox_state->common_attributes,
     prox_sensitivity_addresses,
     ARRAY_SIZE(prox_sensitivity_addresses));
 if (ret) {
  dev_err(&pdev->dev, "failed to setup common attributes\n");
  return ret;
 }

 ret = prox_parse_report(pdev, hsdev, prox_state);
 if (ret) {
  dev_err(&pdev->dev, "failed to setup attributes\n");
  return ret;
 }

 indio_dev->num_channels = prox_state->num_channels;
 indio_dev->channels = prox_state->channels;
 indio_dev->available_scan_masks = prox_state->scan_mask;
 indio_dev->info = &prox_info;
 indio_dev->name = name;
 indio_dev->modes = INDIO_DIRECT_MODE;

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

 ret = hid_sensor_setup_trigger(indio_dev, name,
    &prox_state->common_attributes);
 if (ret) {
  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;
 }

 prox_state->callbacks.send_event = prox_proc_event;
 prox_state->callbacks.capture_sample = prox_capture_sample;
 prox_state->callbacks.pdev = pdev;
 ret = sensor_hub_register_callback(hsdev, hsdev->usage,
        &prox_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, &prox_state->common_attributes);
 return ret;
}

/* Function to deinitialize the processing for usage id */
static void hid_prox_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 prox_state *prox_state = iio_priv(indio_dev);

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

static const struct platform_device_id hid_prox_ids[] = {
 {
  /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
  .name = "HID-SENSOR-200011",
 },
 {
  /* Format: HID-SENSOR-tag-usage_id_in_hex_lowercase */
  .name = "HID-SENSOR-LISS-0226",
 },
 { }
};
MODULE_DEVICE_TABLE(platform, hid_prox_ids);

static struct platform_driver hid_prox_platform_driver = {
 .id_table = hid_prox_ids,
 .driver = {
  .name = KBUILD_MODNAME,
  .pm = &hid_sensor_pm_ops,
 },
 .probe  = hid_prox_probe,
 .remove  = hid_prox_remove,
};
module_platform_driver(hid_prox_platform_driver);

MODULE_DESCRIPTION("HID Sensor Proximity");
MODULE_AUTHOR("Archana Patni ");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID");