Quelle  hid-sensor-custom-intel-hinge.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * HID Sensors Driver
 * Copyright (c) 2020, Intel Corporation.
 */
#include <linux/hid-sensor-hub.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>

#include "../common/hid-sensors/hid-sensor-trigger.h"

enum hinge_channel {
 CHANNEL_SCAN_INDEX_HINGE_ANGLE,
 CHANNEL_SCAN_INDEX_SCREEN_ANGLE,
 CHANNEL_SCAN_INDEX_KEYBOARD_ANGLE,
 CHANNEL_SCAN_INDEX_MAX,
};

#define CHANNEL_SCAN_INDEX_TIMESTAMP CHANNEL_SCAN_INDEX_MAX

static const u32 hinge_addresses[CHANNEL_SCAN_INDEX_MAX] = {
 HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
 HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2),
 HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3)
};

static const char *const hinge_labels[CHANNEL_SCAN_INDEX_MAX] = { "hinge",
          "screen",
          "keyboard" };

struct hinge_state {
 struct iio_dev *indio_dev;
 struct hid_sensor_hub_attribute_info hinge[CHANNEL_SCAN_INDEX_MAX];
 struct hid_sensor_hub_callbacks callbacks;
 struct hid_sensor_common common_attributes;
 const char *labels[CHANNEL_SCAN_INDEX_MAX];
 struct {
  u32 hinge_val[3];
  aligned_s64 timestamp;
 } scan;

 int scale_pre_decml;
 int scale_post_decml;
 int scale_precision;
 int value_offset;
 u64 timestamp;
};

static const u32 hinge_sensitivity_addresses[] = {
 HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1),
};

/* Channel definitions */
static const struct iio_chan_spec hinge_channels[] = {
 {
  .type = IIO_ANGL,
  .indexed = 1,
  .channel = 0,
  .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_HINGE_ANGLE,
  .scan_type = {
   .sign = 's',
   .storagebits = 32,
  },
 }, {
  .type = IIO_ANGL,
  .indexed = 1,
  .channel = 1,
  .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_SCREEN_ANGLE,
  .scan_type = {
   .sign = 's',
   .storagebits = 32,
  },
 }, {
  .type = IIO_ANGL,
  .indexed = 1,
  .channel = 2,
  .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_KEYBOARD_ANGLE,
  .scan_type = {
   .sign = 's',
   .storagebits = 32,
  },
 },
 IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
};

/* Adjust channel real bits based on report descriptor */
static void hinge_adjust_channel_realbits(struct iio_chan_spec *channels,
       int channel, int size)
{
 channels[channel].scan_type.realbits = size * 8;
}

/* Channel read_raw handler */
static int hinge_read_raw(struct iio_dev *indio_dev,
     struct iio_chan_spec const *chan, int *val, int *val2,
     long mask)
{
 struct hinge_state *st = iio_priv(indio_dev);
 struct hid_sensor_hub_device *hsdev;
 int report_id;
 s32 min;

 hsdev = st->common_attributes.hsdev;
 switch (mask) {
 case IIO_CHAN_INFO_RAW:
  hid_sensor_power_state(&st->common_attributes, true);
  report_id = st->hinge[chan->scan_index].report_id;
  min = st->hinge[chan->scan_index].logical_minimum;
  if (report_id < 0) {
   hid_sensor_power_state(&st->common_attributes, false);
   return -EINVAL;
  }

  *val = sensor_hub_input_attr_get_raw_value(st->common_attributes.hsdev,
          hsdev->usage,
          hinge_addresses[chan->scan_index],
          report_id,
          SENSOR_HUB_SYNC, min < 0);

  hid_sensor_power_state(&st->common_attributes, false);
  return IIO_VAL_INT;
 case IIO_CHAN_INFO_SCALE:
  *val = st->scale_pre_decml;
  *val2 = st->scale_post_decml;
  return st->scale_precision;
 case IIO_CHAN_INFO_OFFSET:
  *val = st->value_offset;
  return IIO_VAL_INT;
 case IIO_CHAN_INFO_SAMP_FREQ:
  return hid_sensor_read_samp_freq_value(&st->common_attributes,
             val, val2);
 case IIO_CHAN_INFO_HYSTERESIS:
  return hid_sensor_read_raw_hyst_value(&st->common_attributes,
            val, val2);
 default:
  return -EINVAL;
 }
}

/* Channel write_raw handler */
static int hinge_write_raw(struct iio_dev *indio_dev,
      struct iio_chan_spec const *chan, int val, int val2,
      long mask)
{
 struct hinge_state *st = iio_priv(indio_dev);

 switch (mask) {
 case IIO_CHAN_INFO_SAMP_FREQ:
  return hid_sensor_write_samp_freq_value(&st->common_attributes,
       val, val2);
 case IIO_CHAN_INFO_HYSTERESIS:
  return hid_sensor_write_raw_hyst_value(&st->common_attributes,
             val, val2);
 default:
  return -EINVAL;
 }
}

static int hinge_read_label(struct iio_dev *indio_dev,
       struct iio_chan_spec const *chan, char *label)
{
 struct hinge_state *st = iio_priv(indio_dev);

 return sprintf(label, "%s\n", st->labels[chan->channel]);
}

static const struct iio_info hinge_info = {
 .read_raw = hinge_read_raw,
 .write_raw = hinge_write_raw,
 .read_label = hinge_read_label,
};

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

 if (atomic_read(&st->common_attributes.data_ready)) {
  if (!st->timestamp)
   st->timestamp = iio_get_time_ns(indio_dev);

  iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
         st->timestamp);

  st->timestamp = 0;
 }
 return 0;
}

/* Capture samples in local storage */
static int hinge_capture_sample(struct hid_sensor_hub_device *hsdev,
    unsigned int usage_id, size_t raw_len,
    char *raw_data, void *priv)
{
 struct iio_dev *indio_dev = platform_get_drvdata(priv);
 struct hinge_state *st = iio_priv(indio_dev);
 int offset;

 switch (usage_id) {
 case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1):
 case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(2):
 case HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(3):
  offset = usage_id - HID_USAGE_SENSOR_DATA_FIELD_CUSTOM_VALUE(1);
  st->scan.hinge_val[offset] = *(u32 *)raw_data;
  return 0;
 case HID_USAGE_SENSOR_TIME_TIMESTAMP:
  st->timestamp = hid_sensor_convert_timestamp(&st->common_attributes,
            *(int64_t *)raw_data);
  return 0;
 default:
  return -EINVAL;
 }
}

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

 for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
  ret = sensor_hub_input_get_attribute_info(hsdev,
         HID_INPUT_REPORT,
         usage_id,
         hinge_addresses[i],
         &st->hinge[i]);
  if (ret < 0)
   return ret;

  hinge_adjust_channel_realbits(channels, i, st->hinge[i].size);
 }

 st->scale_precision = hid_sensor_format_scale(HID_USAGE_SENSOR_HINGE,
   &st->hinge[CHANNEL_SCAN_INDEX_HINGE_ANGLE],
   &st->scale_pre_decml, &st->scale_post_decml);

 return ret;
}

/* Function to initialize the processing for usage id */
static int hid_hinge_probe(struct platform_device *pdev)
{
 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
 struct hinge_state *st;
 struct iio_dev *indio_dev;
 int ret;
 int i;

 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
 if (!indio_dev)
  return -ENOMEM;

 platform_set_drvdata(pdev, indio_dev);

 st = iio_priv(indio_dev);
 st->common_attributes.hsdev = hsdev;
 st->common_attributes.pdev = pdev;
 st->indio_dev = indio_dev;
 for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; i++)
  st->labels[i] = hinge_labels[i];

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

 indio_dev->num_channels = ARRAY_SIZE(hinge_channels);
 indio_dev->channels = devm_kmemdup(&indio_dev->dev, hinge_channels,
        sizeof(hinge_channels), GFP_KERNEL);
 if (!indio_dev->channels)
  return -ENOMEM;

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

 indio_dev->info = &hinge_info;
 indio_dev->name = "hinge";
 indio_dev->modes = INDIO_DIRECT_MODE;

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

 st->callbacks.send_event = hinge_proc_event;
 st->callbacks.capture_sample = hinge_capture_sample;
 st->callbacks.pdev = pdev;
 ret = sensor_hub_register_callback(hsdev, hsdev->usage, &st->callbacks);
 if (ret < 0) {
  dev_err(&pdev->dev, "callback reg failed\n");
  goto error_remove_trigger;
 }

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

 return ret;

error_remove_callback:
 sensor_hub_remove_callback(hsdev, hsdev->usage);
error_remove_trigger:
 hid_sensor_remove_trigger(indio_dev, &st->common_attributes);
 return ret;
}

/* Function to deinitialize the processing for usage id */
static void hid_hinge_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 hinge_state *st = iio_priv(indio_dev);

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

static const struct platform_device_id hid_hinge_ids[] = {
 {
  /* Format: HID-SENSOR-INT-usage_id_in_hex_lowercase */
  .name = "HID-SENSOR-INT-020b",
 },
 { }
};
MODULE_DEVICE_TABLE(platform, hid_hinge_ids);

static struct platform_driver hid_hinge_platform_driver = {
 .id_table = hid_hinge_ids,
 .driver = {
  .name = KBUILD_MODNAME,
  .pm = &hid_sensor_pm_ops,
 },
 .probe  = hid_hinge_probe,
 .remove  = hid_hinge_remove,
};
module_platform_driver(hid_hinge_platform_driver);

MODULE_DESCRIPTION("HID Sensor INTEL Hinge");
MODULE_AUTHOR("Ye Xiang ");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID");