// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012 Invensense, Inc.
*/

#include <linux/pm_runtime.h>

#include <linux/iio/common/inv_sensors_timestamp.h>
#include <linux/iio/events.h>

#include "inv_mpu_iio.h"

static unsigned int inv_scan_query_mpu6050(struct iio_dev *indio_dev)
{
        struct inv_mpu6050_state  *st = iio_priv(indio_dev);
        unsigned int mask;

        /*
         * If the MPU6050 is just used as a trigger, then the scan mask
         * is not allocated so we simply enable the temperature channel
         * as a dummy and bail out.
         */
        if (!indio_dev->active_scan_mask) {
                st->chip_config.temp_fifo_enable = true;
                return INV_MPU6050_SENSOR_TEMP;
        }

        st->chip_config.gyro_fifo_enable =
                test_bit(INV_MPU6050_SCAN_GYRO_X,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU6050_SCAN_GYRO_Y,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU6050_SCAN_GYRO_Z,
                         indio_dev->active_scan_mask);

        st->chip_config.accl_fifo_enable =
                test_bit(INV_MPU6050_SCAN_ACCL_X,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU6050_SCAN_ACCL_Y,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU6050_SCAN_ACCL_Z,
                         indio_dev->active_scan_mask);

        st->chip_config.temp_fifo_enable =
                test_bit(INV_MPU6050_SCAN_TEMP, indio_dev->active_scan_mask);

        mask = 0;
        if (st->chip_config.gyro_fifo_enable)
                mask |= INV_MPU6050_SENSOR_GYRO;
        if (st->chip_config.accl_fifo_enable)
                mask |= INV_MPU6050_SENSOR_ACCL;
        if (st->chip_config.temp_fifo_enable)
                mask |= INV_MPU6050_SENSOR_TEMP;

        return mask;
}

static unsigned int inv_scan_query_mpu9x50(struct iio_dev *indio_dev)
{
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
        unsigned int mask;

        mask = inv_scan_query_mpu6050(indio_dev);

        /* no magnetometer if i2c auxiliary bus is used */
        if (st->magn_disabled)
                return mask;

        st->chip_config.magn_fifo_enable =
                test_bit(INV_MPU9X50_SCAN_MAGN_X,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU9X50_SCAN_MAGN_Y,
                         indio_dev->active_scan_mask) ||
                test_bit(INV_MPU9X50_SCAN_MAGN_Z,
                         indio_dev->active_scan_mask);
        if (st->chip_config.magn_fifo_enable)
                mask |= INV_MPU6050_SENSOR_MAGN;

        return mask;
}

static unsigned int inv_scan_query(struct iio_dev *indio_dev)
{
        struct inv_mpu6050_state *st = iio_priv(indio_dev);

        switch (st->chip_type) {
        case INV_MPU9150:
        case INV_MPU9250:
        case INV_MPU9255:
                return inv_scan_query_mpu9x50(indio_dev);
        default:
                return inv_scan_query_mpu6050(indio_dev);
        }
}

static unsigned int inv_compute_skip_samples(const struct inv_mpu6050_state *st)
{
        unsigned int skip_samples = 0;

        /* mag first sample is always not ready, skip it */
        if (st->chip_config.magn_fifo_enable)
                skip_samples = 1;

        return skip_samples;
}

int inv_mpu6050_prepare_fifo(struct inv_mpu6050_state *st, bool enable)
{
        uint8_t d;
        int ret;

        if (enable) {
                /* reset timestamping */
                inv_sensors_timestamp_reset(&st->timestamp);
                /* reset FIFO */
                d = st->chip_config.user_ctrl | INV_MPU6050_BIT_FIFO_RST;
                ret = regmap_write(st->map, st->reg->user_ctrl, d);
                if (ret)
                        return ret;
                /* enable sensor output to FIFO */
                d = 0;
                if (st->chip_config.gyro_fifo_enable)
                        d |= INV_MPU6050_BITS_GYRO_OUT;
                if (st->chip_config.accl_fifo_enable)
                        d |= INV_MPU6050_BIT_ACCEL_OUT;
                if (st->chip_config.temp_fifo_enable)
                        d |= INV_MPU6050_BIT_TEMP_OUT;
                if (st->chip_config.magn_fifo_enable)
                        d |= INV_MPU6050_BIT_SLAVE_0;
                ret = regmap_write(st->map, st->reg->fifo_en, d);
                if (ret)
                        return ret;
                /* enable FIFO reading */
                d = st->chip_config.user_ctrl | INV_MPU6050_BIT_FIFO_EN;
                ret = regmap_write(st->map, st->reg->user_ctrl, d);
                if (ret)
                        return ret;
                /* enable data interrupt */
                ret = regmap_update_bits(st->map, st->reg->int_enable,
                                INV_MPU6050_BIT_DATA_RDY_EN, INV_MPU6050_BIT_DATA_RDY_EN);
        } else {
                /* disable data interrupt */
                ret = regmap_update_bits(st->map, st->reg->int_enable,
                                INV_MPU6050_BIT_DATA_RDY_EN, 0);
                if (ret)
                        return ret;
                ret = regmap_write(st->map, st->reg->fifo_en, 0);
                if (ret)
                        return ret;
                /* restore user_ctrl for disabling FIFO reading */
                ret = regmap_write(st->map, st->reg->user_ctrl,
                                   st->chip_config.user_ctrl);
        }

        return ret;
}

/**
 *  inv_mpu6050_set_enable() - enable chip functions.
 *  @indio_dev: Device driver instance.
 *  @enable: enable/disable
 */
static int inv_mpu6050_set_enable(struct iio_dev *indio_dev, bool enable)
{
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
        struct device *pdev = regmap_get_device(st->map);
        unsigned int scan;
        int result;

        if (enable) {
                scan = inv_scan_query(indio_dev);
                result = pm_runtime_resume_and_get(pdev);
                if (result)
                        return result;
                /*
                 * In case autosuspend didn't trigger, turn off first not
                 * required sensors excepted WoM
                 */
                result = inv_mpu6050_switch_engine(st, false, ~scan & ~INV_MPU6050_SENSOR_WOM);
                if (result)
                        goto error_power_off;
                result = inv_mpu6050_switch_engine(st, true, scan);
                if (result)
                        goto error_power_off;
                st->skip_samples = inv_compute_skip_samples(st);
                result = inv_mpu6050_prepare_fifo(st, true);
                if (result)
                        goto error_power_off;
        } else {
                st->chip_config.gyro_fifo_enable = 0;
                st->chip_config.accl_fifo_enable = 0;
                st->chip_config.temp_fifo_enable = 0;
                st->chip_config.magn_fifo_enable = 0;
                result = inv_mpu6050_prepare_fifo(st, false);
                if (result)
                        goto error_power_off;
                pm_runtime_put_autosuspend(pdev);
        }

        return 0;

error_power_off:
        pm_runtime_put_autosuspend(pdev);
        return result;
}

/**
 * inv_mpu_data_rdy_trigger_set_state() - set data ready interrupt state
 * @trig: Trigger instance
 * @state: Desired trigger state
 */
static int inv_mpu_data_rdy_trigger_set_state(struct iio_trigger *trig,
                                              bool state)
{
        struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
        int result;

        mutex_lock(&st->lock);
        result = inv_mpu6050_set_enable(indio_dev, state);
        mutex_unlock(&st->lock);

        return result;
}

static const struct iio_trigger_ops inv_mpu_trigger_ops = {
        .set_trigger_state = &inv_mpu_data_rdy_trigger_set_state,
};

static irqreturn_t inv_mpu6050_interrupt_timestamp(int irq, void *p)
{
        struct iio_dev *indio_dev = p;
        struct inv_mpu6050_state *st = iio_priv(indio_dev);

        st->it_timestamp = iio_get_time_ns(indio_dev);

        return IRQ_WAKE_THREAD;
}

static irqreturn_t inv_mpu6050_interrupt_handle(int irq, void *p)
{
        struct iio_dev *indio_dev = p;
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
        unsigned int int_status, wom_bits;
        u64 ev_code;
        int result;

        switch (st->chip_type) {
        case INV_MPU6000:
        case INV_MPU6050:
                /*
                 * WoM is not supported and interrupt status read seems to be broken for
                 * some chips. Since data ready is the only interrupt, bypass interrupt
                 * status read and always assert data ready bit.
                 */
                wom_bits = 0;
                int_status = INV_MPU6050_BIT_RAW_DATA_RDY_INT;
                goto data_ready_interrupt;
        case INV_MPU9150:
                /* IRQ needs to be acked */
                wom_bits = 0;
                break;
        case INV_MPU6500:
        case INV_MPU6515:
        case INV_MPU6880:
        case INV_MPU9250:
        case INV_MPU9255:
                wom_bits = INV_MPU6500_BIT_WOM_INT;
                break;
        default:
                wom_bits = INV_ICM20608_BIT_WOM_INT;
                break;
        }

        scoped_guard(mutex, &st->lock) {
                /* ack interrupt and check status */
                result = regmap_read(st->map, st->reg->int_status, &int_status);
                if (result) {
                        dev_err(regmap_get_device(st->map), "failed to ack interrupt\n");
                        return IRQ_HANDLED;
                }

                /* handle WoM event */
                if (st->chip_config.wom_en && (int_status & wom_bits)) {
                        ev_code = IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X_OR_Y_OR_Z,
                                                     IIO_EV_TYPE_ROC, IIO_EV_DIR_RISING);
                        iio_push_event(indio_dev, ev_code, st->it_timestamp);
                }
        }

data_ready_interrupt:
        /* handle raw data interrupt */
        if (int_status & INV_MPU6050_BIT_RAW_DATA_RDY_INT) {
                indio_dev->pollfunc->timestamp = st->it_timestamp;
                iio_trigger_poll_nested(st->trig);
        }

        return IRQ_HANDLED;
}

int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev, int irq_type)
{
        int ret;
        struct inv_mpu6050_state *st = iio_priv(indio_dev);

        st->trig = devm_iio_trigger_alloc(&indio_dev->dev,
                                          "%s-dev%d",
                                          indio_dev->name,
                                          iio_device_id(indio_dev));
        if (!st->trig)
                return -ENOMEM;

        irq_type |= IRQF_ONESHOT;
        ret = devm_request_threaded_irq(&indio_dev->dev, st->irq,
                                        &inv_mpu6050_interrupt_timestamp,
                                        &inv_mpu6050_interrupt_handle,
                                        irq_type, "inv_mpu", indio_dev);
        if (ret)
                return ret;

        st->trig->dev.parent = regmap_get_device(st->map);
        st->trig->ops = &inv_mpu_trigger_ops;
        iio_trigger_set_drvdata(st->trig, indio_dev);

        ret = devm_iio_trigger_register(&indio_dev->dev, st->trig);
        if (ret)
                return ret;

        indio_dev->trig = iio_trigger_get(st->trig);

        return 0;
}