root/drivers/iio/common/ssp_sensors/ssp_iio.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
 */

#include <linux/iio/common/ssp_sensors.h>
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/unaligned.h>
#include <linux/units.h>
#include "ssp_iio_sensor.h"

/**
 * ssp_common_buffer_postenable() - generic postenable callback for ssp buffer
 *
 * @indio_dev:          iio device
 *
 * Returns 0 or negative value in case of error
 */
int ssp_common_buffer_postenable(struct iio_dev *indio_dev)
{
        struct ssp_sensor_data *spd = iio_priv(indio_dev);
        struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);

        /* the allocation is made in post because scan size is known in this
         * moment
         * */
        spd->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL | GFP_DMA);
        if (!spd->buffer)
                return -ENOMEM;

        return ssp_enable_sensor(data, spd->type,
                                 ssp_get_sensor_delay(data, spd->type));
}
EXPORT_SYMBOL_NS(ssp_common_buffer_postenable, "IIO_SSP_SENSORS");

/**
 * ssp_common_buffer_postdisable() - generic postdisable callback for ssp buffer
 *
 * @indio_dev:          iio device
 *
 * Returns 0 or negative value in case of error
 */
int ssp_common_buffer_postdisable(struct iio_dev *indio_dev)
{
        int ret;
        struct ssp_sensor_data *spd = iio_priv(indio_dev);
        struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);

        ret = ssp_disable_sensor(data, spd->type);
        if (ret < 0)
                return ret;

        kfree(spd->buffer);

        return ret;
}
EXPORT_SYMBOL_NS(ssp_common_buffer_postdisable, "IIO_SSP_SENSORS");

/**
 * ssp_common_process_data() - Common process data callback for ssp sensors
 *
 * @indio_dev:          iio device
 * @buf:                source buffer
 * @len:                sensor data length
 * @timestamp:          system timestamp
 *
 * Returns 0 or negative value in case of error
 */
int ssp_common_process_data(struct iio_dev *indio_dev, void *buf,
                            unsigned int len, int64_t timestamp)
{
        int64_t calculated_time;
        struct ssp_sensor_data *spd = iio_priv(indio_dev);

        if (indio_dev->scan_bytes == 0)
                return 0;

        /*
         * it always sends full set of samples, remember about available masks
         */
        memcpy(spd->buffer, buf, len);

        calculated_time = timestamp +
                (int64_t)get_unaligned_le32(buf + len) * MEGA;

        return iio_push_to_buffers_with_timestamp(indio_dev, spd->buffer,
                                                  calculated_time);
}
EXPORT_SYMBOL_NS(ssp_common_process_data, "IIO_SSP_SENSORS");

MODULE_AUTHOR("Karol Wrona <k.wrona@samsung.com>");
MODULE_DESCRIPTION("Samsung sensorhub commons");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_SSP_SENSORS");