// 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"

enum {
        CHANNEL_SCAN_INDEX_PRESSURE,
        CHANNEL_SCAN_INDEX_TIMESTAMP,
};

struct press_state {
        struct hid_sensor_hub_callbacks callbacks;
        struct hid_sensor_common common_attributes;
        struct hid_sensor_hub_attribute_info press_attr;
        struct {
                u32 press_data;
                aligned_s64 timestamp;
        } scan;
        int scale_pre_decml;
        int scale_post_decml;
        int scale_precision;
        int value_offset;
        s64 timestamp;
};

static const u32 press_sensitivity_addresses[] = {
        HID_USAGE_SENSOR_DATA_ATMOSPHERIC_PRESSURE,
        HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE
};

/* Channel definitions */
static const struct iio_chan_spec press_channels[] = {
        {
                .type = IIO_PRESSURE,
                .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_PRESSURE,
        },
        IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)

};

/* Adjust channel real bits based on report descriptor */
static void press_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 press_read_raw(struct iio_dev *indio_dev,
                              struct iio_chan_spec const *chan,
                              int *val, int *val2,
                              long mask)
{
        struct press_state *press_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:
                switch (chan->scan_index) {
                case  CHANNEL_SCAN_INDEX_PRESSURE:
                        report_id = press_state->press_attr.report_id;
                        min = press_state->press_attr.logical_minimum;
                        address = HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE;
                        break;
                default:
                        report_id = -1;
                        break;
                }
                if (report_id >= 0) {
                        hid_sensor_power_state(&press_state->common_attributes,
                                                true);
                        *val = sensor_hub_input_attr_get_raw_value(
                                press_state->common_attributes.hsdev,
                                HID_USAGE_SENSOR_PRESSURE, address,
                                report_id,
                                SENSOR_HUB_SYNC,
                                min < 0);
                        hid_sensor_power_state(&press_state->common_attributes,
                                                false);
                } else {
                        *val = 0;
                        return -EINVAL;
                }
                ret_type = IIO_VAL_INT;
                break;
        case IIO_CHAN_INFO_SCALE:
                *val = press_state->scale_pre_decml;
                *val2 = press_state->scale_post_decml;
                ret_type = press_state->scale_precision;
                break;
        case IIO_CHAN_INFO_OFFSET:
                *val = press_state->value_offset;
                ret_type = IIO_VAL_INT;
                break;
        case IIO_CHAN_INFO_SAMP_FREQ:
                ret_type = hid_sensor_read_samp_freq_value(
                                &press_state->common_attributes, val, val2);
                break;
        case IIO_CHAN_INFO_HYSTERESIS:
                ret_type = hid_sensor_read_raw_hyst_value(
                                &press_state->common_attributes, val, val2);
                break;
        default:
                ret_type = -EINVAL;
                break;
        }

        return ret_type;
}

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

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

        return ret;
}

static const struct iio_info press_info = {
        .read_raw = &press_read_raw,
        .write_raw = &press_write_raw,
};

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

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

                iio_push_to_buffers_with_ts(indio_dev, &press_state->scan,
                                            sizeof(press_state->scan),
                                            press_state->timestamp);
        }

        return 0;
}

/* Capture samples in local storage */
static int press_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 press_state *press_state = iio_priv(indio_dev);
        int ret = -EINVAL;

        switch (usage_id) {
        case HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE:
                press_state->scan.press_data = *(u32 *)raw_data;
                ret = 0;
                break;
        case HID_USAGE_SENSOR_TIME_TIMESTAMP:
                press_state->timestamp = hid_sensor_convert_timestamp(
                        &press_state->common_attributes, *(s64 *)raw_data);
                break;
        default:
                break;
        }

        return ret;
}

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

        ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
                        usage_id,
                        HID_USAGE_SENSOR_ATMOSPHERIC_PRESSURE,
                        &st->press_attr);
        if (ret < 0)
                return ret;
        press_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESSURE,
                                        st->press_attr.size);

        dev_dbg(&pdev->dev, "press %x:%x\n", st->press_attr.index,
                        st->press_attr.report_id);

        st->scale_precision = hid_sensor_format_scale(
                                HID_USAGE_SENSOR_PRESSURE,
                                &st->press_attr,
                                &st->scale_pre_decml, &st->scale_post_decml);

        return ret;
}

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

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

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

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

        indio_dev->channels = devm_kmemdup(&pdev->dev, press_channels,
                                           sizeof(press_channels), GFP_KERNEL);
        if (!indio_dev->channels) {
                dev_err(&pdev->dev, "failed to duplicate channels\n");
                return -ENOMEM;
        }

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

        indio_dev->num_channels =
                                ARRAY_SIZE(press_channels);
        indio_dev->info = &press_info;
        indio_dev->name = name;
        indio_dev->modes = INDIO_DIRECT_MODE;

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

        ret = hid_sensor_setup_trigger(indio_dev, name,
                                &press_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;
        }

        press_state->callbacks.send_event = press_proc_event;
        press_state->callbacks.capture_sample = press_capture_sample;
        press_state->callbacks.pdev = pdev;
        ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PRESSURE,
                                        &press_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, &press_state->common_attributes);
        return ret;
}

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

        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PRESSURE);
        iio_device_unregister(indio_dev);
        hid_sensor_remove_trigger(indio_dev, &press_state->common_attributes);
}

static const struct platform_device_id hid_press_ids[] = {
        {
                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
                .name = "HID-SENSOR-200031",
        },
        { }
};
MODULE_DEVICE_TABLE(platform, hid_press_ids);

static struct platform_driver hid_press_platform_driver = {
        .id_table = hid_press_ids,
        .driver = {
                .name   = KBUILD_MODNAME,
                .pm     = &hid_sensor_pm_ops,
        },
        .probe          = hid_press_probe,
        .remove         = hid_press_remove,
};
module_platform_driver(hid_press_platform_driver);

MODULE_DESCRIPTION("HID Sensor Pressure");
MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID");