// 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/delay.h>
#include <linux/hid-sensor-hub.h>
#include <linux/workqueue.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/kfifo_buf.h>
#include "hid-sensor-trigger.h"

static ssize_t _hid_sensor_set_report_latency(struct device *dev,
                                              struct device_attribute *attr,
                                              const char *buf, size_t len)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
        int integer, fract, ret;
        int latency;

        ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
        if (ret)
                return ret;

        latency = integer * 1000 + fract / 1000;
        ret = hid_sensor_set_report_latency(attrb, latency);
        if (ret < 0)
                return ret;

        attrb->latency_ms = hid_sensor_get_report_latency(attrb);

        return len;
}

static ssize_t _hid_sensor_get_report_latency(struct device *dev,
                                              struct device_attribute *attr,
                                              char *buf)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
        int latency;

        latency = hid_sensor_get_report_latency(attrb);
        if (latency < 0)
                return latency;

        return sprintf(buf, "%d.%06u\n", latency / 1000, (latency % 1000) * 1000);
}

static ssize_t _hid_sensor_get_fifo_state(struct device *dev,
                                          struct device_attribute *attr,
                                          char *buf)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
        int latency;

        latency = hid_sensor_get_report_latency(attrb);
        if (latency < 0)
                return latency;

        return sprintf(buf, "%d\n", !!latency);
}

static IIO_DEVICE_ATTR(hwfifo_timeout, 0644,
                       _hid_sensor_get_report_latency,
                       _hid_sensor_set_report_latency, 0);
static IIO_DEVICE_ATTR(hwfifo_enabled, 0444,
                       _hid_sensor_get_fifo_state, NULL, 0);

static const struct iio_dev_attr *hid_sensor_fifo_attributes[] = {
        &iio_dev_attr_hwfifo_timeout,
        &iio_dev_attr_hwfifo_enabled,
        NULL,
};

static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state)
{
        int state_val;
        int report_val;
        s32 poll_value = 0;

        if (state) {
                if (sensor_hub_device_open(st->hsdev))
                        return -EIO;

                atomic_inc(&st->data_ready);

                state_val = hid_sensor_get_usage_index(st->hsdev,
                        st->power_state.report_id,
                        st->power_state.index,
                        HID_USAGE_SENSOR_PROP_POWER_STATE_D0_FULL_POWER_ENUM);
                report_val = hid_sensor_get_usage_index(st->hsdev,
                        st->report_state.report_id,
                        st->report_state.index,
                        HID_USAGE_SENSOR_PROP_REPORTING_STATE_ALL_EVENTS_ENUM);

                poll_value = hid_sensor_read_poll_value(st);
        } else {
                int val;

                val = atomic_dec_if_positive(&st->data_ready);
                if (val < 0)
                        return 0;

                sensor_hub_device_close(st->hsdev);
                state_val = hid_sensor_get_usage_index(st->hsdev,
                        st->power_state.report_id,
                        st->power_state.index,
                        HID_USAGE_SENSOR_PROP_POWER_STATE_D4_POWER_OFF_ENUM);
                report_val = hid_sensor_get_usage_index(st->hsdev,
                        st->report_state.report_id,
                        st->report_state.index,
                        HID_USAGE_SENSOR_PROP_REPORTING_STATE_NO_EVENTS_ENUM);
        }

        if (state_val >= 0) {
                state_val += st->power_state.logical_minimum;
                sensor_hub_set_feature(st->hsdev, st->power_state.report_id,
                                       st->power_state.index, sizeof(state_val),
                                       &state_val);
        }

        if (report_val >= 0) {
                report_val += st->report_state.logical_minimum;
                sensor_hub_set_feature(st->hsdev, st->report_state.report_id,
                                       st->report_state.index,
                                       sizeof(report_val),
                                       &report_val);
        }

        pr_debug("HID_SENSOR %s set power_state %d report_state %d\n",
                 st->pdev->name, state_val, report_val);

        sensor_hub_get_feature(st->hsdev, st->power_state.report_id,
                               st->power_state.index,
                               sizeof(state_val), &state_val);
        if (state && poll_value)
                msleep_interruptible(poll_value * 2);

        return 0;
}
EXPORT_SYMBOL_NS(hid_sensor_power_state, "IIO_HID");

int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
{

#ifdef CONFIG_PM
        int ret;

        if (atomic_add_unless(&st->runtime_pm_enable, 1, 1))
                pm_runtime_enable(&st->pdev->dev);

        if (state) {
                atomic_inc(&st->user_requested_state);
                ret = pm_runtime_resume_and_get(&st->pdev->dev);
        } else {
                atomic_dec(&st->user_requested_state);
                pm_runtime_use_autosuspend(&st->pdev->dev);
                ret = pm_runtime_put_autosuspend(&st->pdev->dev);
        }
        if (ret < 0)
                return ret;

        return 0;
#else
        atomic_set(&st->user_requested_state, state);
        return _hid_sensor_power_state(st, state);
#endif
}

static void hid_sensor_set_power_work(struct work_struct *work)
{
        struct hid_sensor_common *attrb = container_of(work,
                                                       struct hid_sensor_common,
                                                       work);

        if (attrb->poll_interval >= 0)
                sensor_hub_set_feature(attrb->hsdev, attrb->poll.report_id,
                                       attrb->poll.index,
                                       sizeof(attrb->poll_interval),
                                       &attrb->poll_interval);

        if (attrb->raw_hystersis >= 0)
                sensor_hub_set_feature(attrb->hsdev,
                                       attrb->sensitivity.report_id,
                                       attrb->sensitivity.index,
                                       sizeof(attrb->raw_hystersis),
                                       &attrb->raw_hystersis);

        if (attrb->latency_ms > 0)
                hid_sensor_set_report_latency(attrb, attrb->latency_ms);

        if (atomic_read(&attrb->user_requested_state))
                _hid_sensor_power_state(attrb, true);
}

static int buffer_postenable(struct iio_dev *indio_dev)
{
        return hid_sensor_power_state(iio_device_get_drvdata(indio_dev), 1);
}

static int buffer_predisable(struct iio_dev *indio_dev)
{
        return hid_sensor_power_state(iio_device_get_drvdata(indio_dev), 0);
}

static const struct iio_buffer_setup_ops hid_sensor_buffer_ops = {
        .postenable = buffer_postenable,
        .predisable = buffer_predisable,
};

void hid_sensor_remove_trigger(struct iio_dev *indio_dev,
                               struct hid_sensor_common *attrb)
{
        if (atomic_read(&attrb->runtime_pm_enable))
                pm_runtime_disable(&attrb->pdev->dev);

        pm_runtime_set_suspended(&attrb->pdev->dev);

        cancel_work_sync(&attrb->work);
        iio_trigger_unregister(attrb->trigger);
        iio_trigger_free(attrb->trigger);
}
EXPORT_SYMBOL_NS(hid_sensor_remove_trigger, "IIO_HID");

int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name,
                                struct hid_sensor_common *attrb)
{
        const struct iio_dev_attr **fifo_attrs;
        int ret;
        struct iio_trigger *trig;

        if (hid_sensor_batch_mode_supported(attrb))
                fifo_attrs = hid_sensor_fifo_attributes;
        else
                fifo_attrs = NULL;

        indio_dev->modes = INDIO_DIRECT_MODE | INDIO_HARDWARE_TRIGGERED;

        ret = devm_iio_kfifo_buffer_setup_ext(&indio_dev->dev, indio_dev,
                                              &hid_sensor_buffer_ops,
                                              fifo_attrs);
        if (ret) {
                dev_err(&indio_dev->dev, "Kfifo Buffer Setup Failed\n");
                return ret;
        }

        /*
         * The current user space in distro "iio-sensor-proxy" is not working in
         * trigerless mode and it expects
         * /sys/bus/iio/devices/iio:device0/trigger/current_trigger.
         * The change replacing iio_triggered_buffer_setup_ext() with
         * devm_iio_kfifo_buffer_setup_ext() will not create attribute without
         * registering a trigger with INDIO_HARDWARE_TRIGGERED.
         * So the below code fragment is still required.
         */

        trig = iio_trigger_alloc(indio_dev->dev.parent,
                                 "%s-dev%d", name, iio_device_id(indio_dev));
        if (trig == NULL) {
                dev_err(&indio_dev->dev, "Trigger Allocate Failed\n");
                return -ENOMEM;
        }

        iio_trigger_set_drvdata(trig, attrb);
        ret = iio_trigger_register(trig);

        if (ret) {
                dev_err(&indio_dev->dev, "Trigger Register Failed\n");
                goto error_free_trig;
        }
        attrb->trigger = trig;
        indio_dev->trig = iio_trigger_get(trig);

        ret = pm_runtime_set_active(&indio_dev->dev);
        if (ret)
                goto error_unreg_trigger;

        iio_device_set_drvdata(indio_dev, attrb);

        INIT_WORK(&attrb->work, hid_sensor_set_power_work);

        pm_suspend_ignore_children(&attrb->pdev->dev, true);
        /* Default to 3 seconds, but can be changed from sysfs */
        pm_runtime_set_autosuspend_delay(&attrb->pdev->dev,
                                         3000);
        return ret;
error_unreg_trigger:
        iio_trigger_unregister(trig);
error_free_trig:
        iio_trigger_free(trig);
        return ret;
}
EXPORT_SYMBOL_NS(hid_sensor_setup_trigger, "IIO_HID");

static int __maybe_unused hid_sensor_suspend(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);

        return _hid_sensor_power_state(attrb, false);
}

static int __maybe_unused hid_sensor_resume(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
        schedule_work(&attrb->work);
        return 0;
}

static int __maybe_unused hid_sensor_runtime_resume(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
        return _hid_sensor_power_state(attrb, true);
}

const struct dev_pm_ops hid_sensor_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(hid_sensor_suspend, hid_sensor_resume)
        SET_RUNTIME_PM_OPS(hid_sensor_suspend,
                           hid_sensor_runtime_resume, NULL)
};
EXPORT_SYMBOL_NS(hid_sensor_pm_ops, "IIO_HID");

MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
MODULE_DESCRIPTION("HID Sensor trigger processing");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_HID_ATTRIBUTES");