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linux/drivers/iio/imu/adis_trigger.c
Ramona Gradinariu 01724ce2d9 iio: imu: adis_trigger: Allow level interrupts for FIFO readings
Currently, adis library allows configuration only for edge interrupts,
needed for data ready sampling.
This patch removes the restriction for level interrupts for devices
which have FIFO support.
Furthermore, in case of devices which have FIFO support,
devm_request_threaded_irq is used for interrupt allocation, to avoid
flooding the processor with the FIFO watermark level interrupt, which
is active until enough data has been read from the FIFO.

Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Signed-off-by: Ramona Gradinariu <ramona.bolboaca13@gmail.com>
Link: https://lore.kernel.org/r/20240527142618.275897-7-ramona.bolboaca13@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-06-04 19:53:09 +01:00

107 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Common library for ADIS16XXX devices
*
* Copyright 2012 Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*/
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/export.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/imu/adis.h>
static int adis_data_rdy_trigger_set_state(struct iio_trigger *trig, bool state)
{
struct adis *adis = iio_trigger_get_drvdata(trig);
return adis_enable_irq(adis, state);
}
static const struct iio_trigger_ops adis_trigger_ops = {
.set_trigger_state = &adis_data_rdy_trigger_set_state,
};
static int adis_validate_irq_flag(struct adis *adis)
{
unsigned long direction = adis->irq_flag & IRQF_TRIGGER_MASK;
/* We cannot mask the interrupt so ensure it's not enabled at request */
if (adis->data->unmasked_drdy)
adis->irq_flag |= IRQF_NO_AUTOEN;
/*
* Typically adis devices without FIFO have data ready either on the
* rising edge or on the falling edge of the data ready pin.
* IMU devices with FIFO support have the watermark pin level driven
* either high or low when the FIFO is filled with the desired number
* of samples.
* It defaults to IRQF_TRIGGER_RISING for backward compatibility with
* devices that don't support changing the pin polarity.
*/
if (direction == IRQF_TRIGGER_NONE) {
adis->irq_flag |= IRQF_TRIGGER_RISING;
return 0;
} else if (direction != IRQF_TRIGGER_RISING &&
direction != IRQF_TRIGGER_FALLING && !adis->data->has_fifo) {
dev_err(&adis->spi->dev, "Invalid IRQ mask: %08lx\n",
adis->irq_flag);
return -EINVAL;
} else if (direction != IRQF_TRIGGER_HIGH &&
direction != IRQF_TRIGGER_LOW && adis->data->has_fifo) {
dev_err(&adis->spi->dev, "Invalid IRQ mask: %08lx\n",
adis->irq_flag);
return -EINVAL;
}
return 0;
}
/**
* devm_adis_probe_trigger() - Sets up trigger for a managed adis device
* @adis: The adis device
* @indio_dev: The IIO device
*
* Returns 0 on success or a negative error code
*/
int devm_adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
{
int ret;
adis->trig = devm_iio_trigger_alloc(&adis->spi->dev, "%s-dev%d",
indio_dev->name,
iio_device_id(indio_dev));
if (!adis->trig)
return -ENOMEM;
adis->trig->ops = &adis_trigger_ops;
iio_trigger_set_drvdata(adis->trig, adis);
ret = adis_validate_irq_flag(adis);
if (ret)
return ret;
if (adis->data->has_fifo)
ret = devm_request_threaded_irq(&adis->spi->dev, adis->spi->irq,
NULL,
&iio_trigger_generic_data_rdy_poll,
adis->irq_flag | IRQF_ONESHOT,
indio_dev->name,
adis->trig);
else
ret = devm_request_irq(&adis->spi->dev, adis->spi->irq,
&iio_trigger_generic_data_rdy_poll,
adis->irq_flag,
indio_dev->name,
adis->trig);
if (ret)
return ret;
return devm_iio_trigger_register(&adis->spi->dev, adis->trig);
}
EXPORT_SYMBOL_NS_GPL(devm_adis_probe_trigger, IIO_ADISLIB);