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

struct dev_rot_state {
        struct hid_sensor_hub_callbacks callbacks;
        struct hid_sensor_common common_attributes;
        struct hid_sensor_hub_attribute_info quaternion;
        struct {
                IIO_DECLARE_QUATERNION(s32, sampled_vals);
                /*
                 * ABI regression avoidance: There are two copies of the same
                 * timestamp in case of userspace depending on broken alignment
                 * from older kernels.
                 */
                aligned_s64 timestamp[2];
        } scan;
        int scale_pre_decml;
        int scale_post_decml;
        int scale_precision;
        int value_offset;
        s64 timestamp;
};

static const u32 rotation_sensitivity_addresses[] = {
        HID_USAGE_SENSOR_DATA_ORIENTATION,
        HID_USAGE_SENSOR_ORIENT_QUATERNION,
};

enum {
        DEV_ROT_SCAN_TYPE_16BIT,
        DEV_ROT_SCAN_TYPE_32BIT,
};

static const struct iio_scan_type dev_rot_scan_types[] = {
        [DEV_ROT_SCAN_TYPE_16BIT] = {
                .sign = 's',
                .realbits = 16,
                /* Storage bits has to stay 32 to not break userspace. */
                .storagebits = 32,
                .repeat = 4,
        },
        [DEV_ROT_SCAN_TYPE_32BIT] = {
                .sign = 's',
                .realbits = 32,
                .storagebits = 32,
                .repeat = 4,
        },
};

/* Channel definitions */
static const struct iio_chan_spec dev_rot_channels[] = {
        {
                .type = IIO_ROT,
                .modified = 1,
                .channel2 = IIO_MOD_QUATERNION,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
                                        BIT(IIO_CHAN_INFO_OFFSET) |
                                        BIT(IIO_CHAN_INFO_SCALE) |
                                        BIT(IIO_CHAN_INFO_HYSTERESIS),
                .scan_index = 0,
                .has_ext_scan_type = 1,
                .ext_scan_type = dev_rot_scan_types,
                .num_ext_scan_type = ARRAY_SIZE(dev_rot_scan_types),
        },
        IIO_CHAN_SOFT_TIMESTAMP(1)
};

/* Channel read_raw handler */
static int dev_rot_read_raw(struct iio_dev *indio_dev,
                                struct iio_chan_spec const *chan,
                                int size, int *vals, int *val_len,
                                long mask)
{
        struct dev_rot_state *rot_state = iio_priv(indio_dev);
        struct hid_sensor_hub_device *hsdev = rot_state->common_attributes.hsdev;
        struct hid_sensor_hub_attribute_info *info = &rot_state->quaternion;
        u32 usage_id = HID_USAGE_SENSOR_ORIENT_QUATERNION;
        union {
                s16 val16[4];
                s32 val32[4];
        } raw_buf;
        int ret_type;
        int i;

        vals[0] = 0;
        vals[1] = 0;

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (size >= 4) {
                        if (info->size <= 0 || info->size > sizeof(raw_buf))
                                return -EINVAL;

                        hid_sensor_power_state(&rot_state->common_attributes, true);

                        ret_type = sensor_hub_input_attr_read_values(hsdev,
                                                                     hsdev->usage,
                                                                     usage_id,
                                                                     info->report_id,
                                                                     SENSOR_HUB_SYNC,
                                                                     info->size,
                                                                     (u8 *)&raw_buf);

                        hid_sensor_power_state(&rot_state->common_attributes, false);

                        if (ret_type < 0)
                                return ret_type;

                        switch (info->size) {
                        case sizeof(raw_buf.val16):
                                for (i = 0; i < ARRAY_SIZE(raw_buf.val16); i++)
                                        vals[i] = raw_buf.val16[i];
                                break;
                        case sizeof(raw_buf.val32):
                                for (i = 0; i < ARRAY_SIZE(raw_buf.val32); i++)
                                        vals[i] = raw_buf.val32[i];
                                break;
                        default:
                                return -EINVAL;
                        }

                        ret_type = IIO_VAL_INT_MULTIPLE;
                        *val_len =  4;
                } else
                        ret_type = -EINVAL;
                break;
        case IIO_CHAN_INFO_SCALE:
                vals[0] = rot_state->scale_pre_decml;
                vals[1] = rot_state->scale_post_decml;
                return rot_state->scale_precision;

        case IIO_CHAN_INFO_OFFSET:
                *vals = rot_state->value_offset;
                return IIO_VAL_INT;

        case IIO_CHAN_INFO_SAMP_FREQ:
                ret_type = hid_sensor_read_samp_freq_value(
                        &rot_state->common_attributes, &vals[0], &vals[1]);
                break;
        case IIO_CHAN_INFO_HYSTERESIS:
                ret_type = hid_sensor_read_raw_hyst_value(
                        &rot_state->common_attributes, &vals[0], &vals[1]);
                break;
        default:
                ret_type = -EINVAL;
                break;
        }

        return ret_type;
}

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

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

        return ret;
}

static int dev_rot_get_current_scan_type(const struct iio_dev *indio_dev,
                                         const struct iio_chan_spec *chan)
{
        struct dev_rot_state *rot_state = iio_priv(indio_dev);

        switch (rot_state->quaternion.size / 4) {
        case sizeof(s16):
                return DEV_ROT_SCAN_TYPE_16BIT;
        case sizeof(s32):
                return DEV_ROT_SCAN_TYPE_32BIT;
        default:
                return -EINVAL;
        }
}

static const struct iio_info dev_rot_info = {
        .read_raw_multi = &dev_rot_read_raw,
        .write_raw = &dev_rot_write_raw,
        .get_current_scan_type = &dev_rot_get_current_scan_type,
};

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

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

                /*
                 * ABI regression avoidance: IIO previously had an incorrect
                 * implementation of iio_push_to_buffers_with_timestamp() that
                 * put the timestamp in the last 8 bytes of the buffer, which
                 * was incorrect according to the IIO ABI. To avoid breaking
                 * userspace that may be depending on this broken behavior, we
                 * put the timestamp in both the correct place [0] and the old
                 * incorrect place [1].
                 */
                rot_state->scan.timestamp[0] = rot_state->timestamp;
                rot_state->scan.timestamp[1] = rot_state->timestamp;

                iio_push_to_buffers(indio_dev, &rot_state->scan);

                rot_state->timestamp = 0;
        }

        return 0;
}

/* Capture samples in local storage */
static int dev_rot_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 dev_rot_state *rot_state = iio_priv(indio_dev);

        if (usage_id == HID_USAGE_SENSOR_ORIENT_QUATERNION) {
                if (raw_len / 4 == sizeof(s16)) {
                        rot_state->scan.sampled_vals[0] = ((s16 *)raw_data)[0];
                        rot_state->scan.sampled_vals[1] = ((s16 *)raw_data)[1];
                        rot_state->scan.sampled_vals[2] = ((s16 *)raw_data)[2];
                        rot_state->scan.sampled_vals[3] = ((s16 *)raw_data)[3];
                } else {
                        memcpy(&rot_state->scan.sampled_vals, raw_data,
                               sizeof(rot_state->scan.sampled_vals));
                }

                dev_dbg(&indio_dev->dev, "Recd Quat len:%zu::%zu\n", raw_len,
                        sizeof(rot_state->scan.sampled_vals));
        } else if (usage_id == HID_USAGE_SENSOR_TIME_TIMESTAMP) {
                rot_state->timestamp = hid_sensor_convert_timestamp(&rot_state->common_attributes,
                                                                    *(s64 *)raw_data);
        }

        return 0;
}

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

        ret = sensor_hub_input_get_attribute_info(hsdev,
                                HID_INPUT_REPORT,
                                usage_id,
                                HID_USAGE_SENSOR_ORIENT_QUATERNION,
                                &st->quaternion);
        if (ret)
                return ret;

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

        dev_dbg(&pdev->dev, "dev_rot: attrib size %d\n",
                                st->quaternion.size);

        st->scale_precision = hid_sensor_format_scale(
                                hsdev->usage,
                                &st->quaternion,
                                &st->scale_pre_decml, &st->scale_post_decml);

        return 0;
}

/* Function to initialize the processing for usage id */
static int hid_dev_rot_probe(struct platform_device *pdev)
{
        struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
        int ret;
        char *name;
        struct iio_dev *indio_dev;
        struct dev_rot_state *rot_state;

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

        platform_set_drvdata(pdev, indio_dev);

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

        switch (hsdev->usage) {
        case HID_USAGE_SENSOR_DEVICE_ORIENTATION:
                name = "dev_rotation";
                break;
        case HID_USAGE_SENSOR_RELATIVE_ORIENTATION:
                name = "relative_orientation";
                break;
        case HID_USAGE_SENSOR_GEOMAGNETIC_ORIENTATION:
                name = "geomagnetic_orientation";
                break;
        default:
                return -EINVAL;
        }

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

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

        indio_dev->channels = dev_rot_channels;
        indio_dev->num_channels = ARRAY_SIZE(dev_rot_channels);
        indio_dev->info = &dev_rot_info;
        indio_dev->name = name;
        indio_dev->modes = INDIO_DIRECT_MODE;

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

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

        rot_state->callbacks.send_event = dev_rot_proc_event;
        rot_state->callbacks.capture_sample = dev_rot_capture_sample;
        rot_state->callbacks.pdev = pdev;
        ret = sensor_hub_register_callback(hsdev, hsdev->usage,
                                        &rot_state->callbacks);
        if (ret) {
                dev_err(&pdev->dev, "callback reg failed\n");
                goto error_iio_unreg;
        }

        return 0;

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

/* Function to deinitialize the processing for usage id */
static void hid_dev_rot_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 dev_rot_state *rot_state = iio_priv(indio_dev);

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

static const struct platform_device_id hid_dev_rot_ids[] = {
        {
                /* Format: HID-SENSOR-usage_id_in_hex_lowercase */
                .name = "HID-SENSOR-20008a",
        },
        {
                /* Relative orientation(AG) sensor */
                .name = "HID-SENSOR-20008e",
        },
        {
                /* Geomagnetic orientation(AM) sensor */
                .name = "HID-SENSOR-2000c1",
        },
        { }
};
MODULE_DEVICE_TABLE(platform, hid_dev_rot_ids);

static struct platform_driver hid_dev_rot_platform_driver = {
        .id_table = hid_dev_rot_ids,
        .driver = {
                .name   = KBUILD_MODNAME,
                .pm     = &hid_sensor_pm_ops,
        },
        .probe          = hid_dev_rot_probe,
        .remove         = hid_dev_rot_remove,
};
module_platform_driver(hid_dev_rot_platform_driver);

MODULE_DESCRIPTION("HID Sensor Device Rotation");
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID");