linux/drivers/iio/amplifiers/ad8366.c

// SPDX-License-Identifier: GPL-2.0
/*
 * AD8366 and similar Gain Amplifiers
 * This driver supports the following gain amplifiers:
 *   AD8366 Dual-Digital Variable Gain Amplifier (VGA)
 *   ADA4961 BiCMOS RF Digital Gain Amplifier (DGA)
 *   ADL5240 Digitally controlled variable gain amplifier (VGA)
 *   HMC792A 0.25 dB LSB GaAs MMIC 6-Bit Digital Attenuator
 *   HMC1119 0.25 dB LSB, 7-Bit, Silicon Digital Attenuator
 *
 * Copyright 2012-2019 Analog Devices Inc.
 */

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio/consumer.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/bitrev.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

enum ad8366_type { … };

struct ad8366_info { … };

struct ad8366_state { … };

static struct ad8366_info ad8366_infos[] = …;

static int ad8366_write(struct iio_dev *indio_dev,
			unsigned char ch_a, unsigned char ch_b)
{ … }

static int ad8366_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val,
			   int *val2,
			   long m)
{
	struct ad8366_state *st = iio_priv(indio_dev);
	int ret;
	int code, gain = 0;

	mutex_lock(&st->lock);
	switch (m) {
	case IIO_CHAN_INFO_HARDWAREGAIN:
		code = st->ch[chan->channel];

		switch (st->type) {
		case ID_AD8366:
			gain = code * 253 + 4500;
			break;
		case ID_ADA4961:
			gain = 15000 - code * 1000;
			break;
		case ID_ADL5240:
			gain = 20000 - 31500 + code * 500;
			break;
		case ID_HMC792:
			gain = -1 * code * 500;
			break;
		case ID_HMC1119:
			gain = -1 * code * 250;
			break;
		}

		/* Values in dB */
		*val = gain / 1000;
		*val2 = (gain % 1000) * 1000;

		ret = IIO_VAL_INT_PLUS_MICRO_DB;
		break;
	default:
		ret = -EINVAL;
	}
	mutex_unlock(&st->lock);

	return ret;
};

static int ad8366_write_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int val,
			    int val2,
			    long mask)
{ … }

static int ad8366_write_raw_get_fmt(struct iio_dev *indio_dev,
				    struct iio_chan_spec const *chan,
				    long mask)
{ … }

static const struct iio_info ad8366_info = …;

#define AD8366_CHAN(_channel) …

static const struct iio_chan_spec ad8366_channels[] = …;

static const struct iio_chan_spec ada4961_channels[] = …;

static int ad8366_probe(struct spi_device *spi)
{ … }

static void ad8366_remove(struct spi_device *spi)
{ … }

static const struct spi_device_id ad8366_id[] = …;
MODULE_DEVICE_TABLE(spi, ad8366_id);

static struct spi_driver ad8366_driver = …;

module_spi_driver(…) …;

MODULE_AUTHOR(…) …;
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;