Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 378 insertions, 0 deletions

diff --git a/drivers/iio/adc/ad7780.c b/drivers/iio/adc/ad7780.c
new file mode 100644
index 0000000000..a813fe0478
--- /dev/null
+++ b/drivers/iio/adc/ad7780.c
@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AD7170/AD7171 and AD7780/AD7781 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ * Copyright 2019 Renato Lui Geh
+ */
+
+#include <linux/interrupt.h>
+#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/err.h>
+#include <linux/sched.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/bits.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/adc/ad_sigma_delta.h>
+
+#define AD7780_RDY		BIT(7)
+#define AD7780_FILTER		BIT(6)
+#define AD7780_ERR		BIT(5)
+#define AD7780_ID1		BIT(4)
+#define AD7780_ID0		BIT(3)
+#define AD7780_GAIN		BIT(2)
+
+#define AD7170_ID		0
+#define AD7171_ID		1
+#define AD7780_ID		1
+#define AD7781_ID		0
+
+#define AD7780_ID_MASK		(AD7780_ID0 | AD7780_ID1)
+
+#define AD7780_PATTERN_GOOD	1
+#define AD7780_PATTERN_MASK	GENMASK(1, 0)
+
+#define AD7170_PATTERN_GOOD	5
+#define AD7170_PATTERN_MASK	GENMASK(2, 0)
+
+#define AD7780_GAIN_MIDPOINT	64
+#define AD7780_FILTER_MIDPOINT	13350
+
+static const unsigned int ad778x_gain[2]      = { 1, 128 };
+static const unsigned int ad778x_odr_avail[2] = { 10000, 16700 };
+
+struct ad7780_chip_info {
+	struct iio_chan_spec	channel;
+	unsigned int		pattern_mask;
+	unsigned int		pattern;
+	bool			is_ad778x;
+};
+
+struct ad7780_state {
+	const struct ad7780_chip_info	*chip_info;
+	struct regulator		*reg;
+	struct gpio_desc		*powerdown_gpio;
+	struct gpio_desc		*gain_gpio;
+	struct gpio_desc		*filter_gpio;
+	unsigned int			gain;
+	unsigned int			odr;
+	unsigned int			int_vref_mv;
+
+	struct ad_sigma_delta sd;
+};
+
+enum ad7780_supported_device_ids {
+	ID_AD7170,
+	ID_AD7171,
+	ID_AD7780,
+	ID_AD7781,
+};
+
+static struct ad7780_state *ad_sigma_delta_to_ad7780(struct ad_sigma_delta *sd)
+{
+	return container_of(sd, struct ad7780_state, sd);
+}
+
+static int ad7780_set_mode(struct ad_sigma_delta *sigma_delta,
+			   enum ad_sigma_delta_mode mode)
+{
+	struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
+	unsigned int val;
+
+	switch (mode) {
+	case AD_SD_MODE_SINGLE:
+	case AD_SD_MODE_CONTINUOUS:
+		val = 1;
+		break;
+	default:
+		val = 0;
+		break;
+	}
+
+	gpiod_set_value(st->powerdown_gpio, val);
+
+	return 0;
+}
+
+static int ad7780_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad7780_state *st = iio_priv(indio_dev);
+	int voltage_uv;
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
+	case IIO_CHAN_INFO_SCALE:
+		voltage_uv = regulator_get_voltage(st->reg);
+		if (voltage_uv < 0)
+			return voltage_uv;
+		voltage_uv /= 1000;
+		*val = voltage_uv * st->gain;
+		*val2 = chan->scan_type.realbits - 1;
+		st->int_vref_mv = voltage_uv;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	case IIO_CHAN_INFO_OFFSET:
+		*val = -(1 << (chan->scan_type.realbits - 1));
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = st->odr;
+		return IIO_VAL_INT;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int ad7780_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long m)
+{
+	struct ad7780_state *st = iio_priv(indio_dev);
+	const struct ad7780_chip_info *chip_info = st->chip_info;
+	unsigned long long vref;
+	unsigned int full_scale, gain;
+
+	if (!chip_info->is_ad778x)
+		return -EINVAL;
+
+	switch (m) {
+	case IIO_CHAN_INFO_SCALE:
+		if (val != 0)
+			return -EINVAL;
+
+		vref = st->int_vref_mv * 1000000LL;
+		full_scale = 1 << (chip_info->channel.scan_type.realbits - 1);
+		gain = DIV_ROUND_CLOSEST_ULL(vref, full_scale);
+		gain = DIV_ROUND_CLOSEST(gain, val2);
+		st->gain = gain;
+		if (gain < AD7780_GAIN_MIDPOINT)
+			gain = 0;
+		else
+			gain = 1;
+		gpiod_set_value(st->gain_gpio, gain);
+		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT)
+			val = 0;
+		else
+			val = 1;
+		st->odr = ad778x_odr_avail[val];
+		gpiod_set_value(st->filter_gpio, val);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
+				     unsigned int raw_sample)
+{
+	struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
+	const struct ad7780_chip_info *chip_info = st->chip_info;
+
+	if ((raw_sample & AD7780_ERR) ||
+	    ((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
+		return -EIO;
+
+	if (chip_info->is_ad778x) {
+		st->gain = ad778x_gain[raw_sample & AD7780_GAIN];
+		st->odr = ad778x_odr_avail[raw_sample & AD7780_FILTER];
+	}
+
+	return 0;
+}
+
+static const struct ad_sigma_delta_info ad7780_sigma_delta_info = {
+	.set_mode = ad7780_set_mode,
+	.postprocess_sample = ad7780_postprocess_sample,
+	.has_registers = false,
+	.irq_flags = IRQF_TRIGGER_FALLING,
+};
+
+#define _AD7780_CHANNEL(_bits, _wordsize, _mask_all)		\
+{								\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.channel = 0,						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+		BIT(IIO_CHAN_INFO_OFFSET),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.info_mask_shared_by_all = _mask_all,			\
+	.scan_index = 1,					\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = (_bits),				\
+		.storagebits = 32,				\
+		.shift = (_wordsize) - (_bits),			\
+		.endianness = IIO_BE,				\
+	},							\
+}
+
+#define AD7780_CHANNEL(_bits, _wordsize)	\
+	_AD7780_CHANNEL(_bits, _wordsize, BIT(IIO_CHAN_INFO_SAMP_FREQ))
+#define AD7170_CHANNEL(_bits, _wordsize)	\
+	_AD7780_CHANNEL(_bits, _wordsize, 0)
+
+static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
+	[ID_AD7170] = {
+		.channel = AD7170_CHANNEL(12, 24),
+		.pattern = AD7170_PATTERN_GOOD,
+		.pattern_mask = AD7170_PATTERN_MASK,
+		.is_ad778x = false,
+	},
+	[ID_AD7171] = {
+		.channel = AD7170_CHANNEL(16, 24),
+		.pattern = AD7170_PATTERN_GOOD,
+		.pattern_mask = AD7170_PATTERN_MASK,
+		.is_ad778x = false,
+	},
+	[ID_AD7780] = {
+		.channel = AD7780_CHANNEL(24, 32),
+		.pattern = AD7780_PATTERN_GOOD,
+		.pattern_mask = AD7780_PATTERN_MASK,
+		.is_ad778x = true,
+	},
+	[ID_AD7781] = {
+		.channel = AD7780_CHANNEL(20, 32),
+		.pattern = AD7780_PATTERN_GOOD,
+		.pattern_mask = AD7780_PATTERN_MASK,
+		.is_ad778x = true,
+	},
+};
+
+static const struct iio_info ad7780_info = {
+	.read_raw = ad7780_read_raw,
+	.write_raw = ad7780_write_raw,
+};
+
+static int ad7780_init_gpios(struct device *dev, struct ad7780_state *st)
+{
+	int ret;
+
+	st->powerdown_gpio = devm_gpiod_get_optional(dev,
+						     "powerdown",
+						     GPIOD_OUT_LOW);
+	if (IS_ERR(st->powerdown_gpio)) {
+		ret = PTR_ERR(st->powerdown_gpio);
+		dev_err(dev, "Failed to request powerdown GPIO: %d\n", ret);
+		return ret;
+	}
+
+	if (!st->chip_info->is_ad778x)
+		return 0;
+
+
+	st->gain_gpio = devm_gpiod_get_optional(dev,
+						"adi,gain",
+						GPIOD_OUT_HIGH);
+	if (IS_ERR(st->gain_gpio)) {
+		ret = PTR_ERR(st->gain_gpio);
+		dev_err(dev, "Failed to request gain GPIO: %d\n", ret);
+		return ret;
+	}
+
+	st->filter_gpio = devm_gpiod_get_optional(dev,
+						  "adi,filter",
+						  GPIOD_OUT_HIGH);
+	if (IS_ERR(st->filter_gpio)) {
+		ret = PTR_ERR(st->filter_gpio);
+		dev_err(dev, "Failed to request filter GPIO: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void ad7780_reg_disable(void *reg)
+{
+	regulator_disable(reg);
+}
+
+static int ad7780_probe(struct spi_device *spi)
+{
+	struct ad7780_state *st;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->gain = 1;
+
+	ad_sd_init(&st->sd, indio_dev, spi, &ad7780_sigma_delta_info);
+
+	st->chip_info =
+		&ad7780_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = &st->chip_info->channel;
+	indio_dev->num_channels = 1;
+	indio_dev->info = &ad7780_info;
+
+	ret = ad7780_init_gpios(&spi->dev, st);
+	if (ret)
+		return ret;
+
+	st->reg = devm_regulator_get(&spi->dev, "avdd");
+	if (IS_ERR(st->reg))
+		return PTR_ERR(st->reg);
+
+	ret = regulator_enable(st->reg);
+	if (ret) {
+		dev_err(&spi->dev, "Failed to enable specified AVdd supply\n");
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(&spi->dev, ad7780_reg_disable, st->reg);
+	if (ret)
+		return ret;
+
+	ret = devm_ad_sd_setup_buffer_and_trigger(&spi->dev, indio_dev);
+	if (ret)
+		return ret;
+
+	return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id ad7780_id[] = {
+	{"ad7170", ID_AD7170},
+	{"ad7171", ID_AD7171},
+	{"ad7780", ID_AD7780},
+	{"ad7781", ID_AD7781},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ad7780_id);
+
+static struct spi_driver ad7780_driver = {
+	.driver = {
+		.name	= "ad7780",
+	},
+	.probe		= ad7780_probe,
+	.id_table	= ad7780_id,
+};
+module_spi_driver(ad7780_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD7780 and similar ADCs");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA);