Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 455 insertions, 0 deletions

diff --git a/drivers/iio/adc/ad7476.c b/drivers/iio/adc/ad7476.c
new file mode 100644
index 0000000000..80aebed47d
--- /dev/null
+++ b/drivers/iio/adc/ad7476.c
@@ -0,0 +1,455 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver
+ * TI ADC081S/ADC101S/ADC121S 8/10/12-bit SPI ADC driver
+ *
+ * Copyright 2010 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/bitops.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+struct ad7476_state;
+
+struct ad7476_chip_info {
+	unsigned int			int_vref_uv;
+	struct iio_chan_spec		channel[2];
+	/* channels used when convst gpio is defined */
+	struct iio_chan_spec		convst_channel[2];
+	void (*reset)(struct ad7476_state *);
+	bool				has_vref;
+	bool				has_vdrive;
+};
+
+struct ad7476_state {
+	struct spi_device		*spi;
+	const struct ad7476_chip_info	*chip_info;
+	struct regulator		*ref_reg;
+	struct gpio_desc		*convst_gpio;
+	struct spi_transfer		xfer;
+	struct spi_message		msg;
+	/*
+	 * DMA (thus cache coherency maintenance) may require the
+	 * transfer buffers to live in their own cache lines.
+	 * Make the buffer large enough for one 16 bit sample and one 64 bit
+	 * aligned 64 bit timestamp.
+	 */
+	unsigned char data[ALIGN(2, sizeof(s64)) + sizeof(s64)] __aligned(IIO_DMA_MINALIGN);
+};
+
+enum ad7476_supported_device_ids {
+	ID_AD7091,
+	ID_AD7091R,
+	ID_AD7273,
+	ID_AD7274,
+	ID_AD7276,
+	ID_AD7277,
+	ID_AD7278,
+	ID_AD7466,
+	ID_AD7467,
+	ID_AD7468,
+	ID_AD7475,
+	ID_AD7495,
+	ID_AD7940,
+	ID_ADC081S,
+	ID_ADC101S,
+	ID_ADC121S,
+	ID_ADS7866,
+	ID_ADS7867,
+	ID_ADS7868,
+	ID_LTC2314_14,
+};
+
+static void ad7091_convst(struct ad7476_state *st)
+{
+	if (!st->convst_gpio)
+		return;
+
+	gpiod_set_value(st->convst_gpio, 0);
+	udelay(1); /* CONVST pulse width: 10 ns min */
+	gpiod_set_value(st->convst_gpio, 1);
+	udelay(1); /* Conversion time: 650 ns max */
+}
+
+static irqreturn_t ad7476_trigger_handler(int irq, void  *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct ad7476_state *st = iio_priv(indio_dev);
+	int b_sent;
+
+	ad7091_convst(st);
+
+	b_sent = spi_sync(st->spi, &st->msg);
+	if (b_sent < 0)
+		goto done;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, st->data,
+		iio_get_time_ns(indio_dev));
+done:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static void ad7091_reset(struct ad7476_state *st)
+{
+	/* Any transfers with 8 scl cycles will reset the device */
+	spi_read(st->spi, st->data, 1);
+}
+
+static int ad7476_scan_direct(struct ad7476_state *st)
+{
+	int ret;
+
+	ad7091_convst(st);
+
+	ret = spi_sync(st->spi, &st->msg);
+	if (ret)
+		return ret;
+
+	return be16_to_cpup((__be16 *)st->data);
+}
+
+static int ad7476_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	int ret;
+	struct ad7476_state *st = iio_priv(indio_dev);
+	int scale_uv;
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+		ret = ad7476_scan_direct(st);
+		iio_device_release_direct_mode(indio_dev);
+
+		if (ret < 0)
+			return ret;
+		*val = (ret >> st->chip_info->channel[0].scan_type.shift) &
+			GENMASK(st->chip_info->channel[0].scan_type.realbits - 1, 0);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		if (st->ref_reg) {
+			scale_uv = regulator_get_voltage(st->ref_reg);
+			if (scale_uv < 0)
+				return scale_uv;
+		} else {
+			scale_uv = st->chip_info->int_vref_uv;
+		}
+		*val = scale_uv / 1000;
+		*val2 = chan->scan_type.realbits;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	}
+	return -EINVAL;
+}
+
+#define _AD7476_CHAN(bits, _shift, _info_mask_sep)		\
+	{							\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.info_mask_separate = _info_mask_sep,			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = (bits),				\
+		.storagebits = 16,				\
+		.shift = (_shift),				\
+		.endianness = IIO_BE,				\
+	},							\
+}
+
+#define ADC081S_CHAN(bits) _AD7476_CHAN((bits), 12 - (bits), \
+		BIT(IIO_CHAN_INFO_RAW))
+#define AD7476_CHAN(bits) _AD7476_CHAN((bits), 13 - (bits), \
+		BIT(IIO_CHAN_INFO_RAW))
+#define AD7940_CHAN(bits) _AD7476_CHAN((bits), 15 - (bits), \
+		BIT(IIO_CHAN_INFO_RAW))
+#define AD7091R_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), 0)
+#define AD7091R_CONVST_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), \
+		BIT(IIO_CHAN_INFO_RAW))
+#define ADS786X_CHAN(bits) _AD7476_CHAN((bits), 12 - (bits), \
+		BIT(IIO_CHAN_INFO_RAW))
+
+static const struct ad7476_chip_info ad7476_chip_info_tbl[] = {
+	[ID_AD7091] = {
+		.channel[0] = AD7091R_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.convst_channel[0] = AD7091R_CONVST_CHAN(12),
+		.convst_channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.reset = ad7091_reset,
+	},
+	[ID_AD7091R] = {
+		.channel[0] = AD7091R_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.convst_channel[0] = AD7091R_CONVST_CHAN(12),
+		.convst_channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.int_vref_uv = 2500000,
+		.has_vref = true,
+		.reset = ad7091_reset,
+	},
+	[ID_AD7273] = {
+		.channel[0] = AD7940_CHAN(10),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.has_vref = true,
+	},
+	[ID_AD7274] = {
+		.channel[0] = AD7940_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.has_vref = true,
+	},
+	[ID_AD7276] = {
+		.channel[0] = AD7940_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7277] = {
+		.channel[0] = AD7940_CHAN(10),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7278] = {
+		.channel[0] = AD7940_CHAN(8),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7466] = {
+		.channel[0] = AD7476_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7467] = {
+		.channel[0] = AD7476_CHAN(10),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7468] = {
+		.channel[0] = AD7476_CHAN(8),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_AD7475] = {
+		.channel[0] = AD7476_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.has_vref = true,
+		.has_vdrive = true,
+	},
+	[ID_AD7495] = {
+		.channel[0] = AD7476_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.int_vref_uv = 2500000,
+		.has_vdrive = true,
+	},
+	[ID_AD7940] = {
+		.channel[0] = AD7940_CHAN(14),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADC081S] = {
+		.channel[0] = ADC081S_CHAN(8),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADC101S] = {
+		.channel[0] = ADC081S_CHAN(10),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADC121S] = {
+		.channel[0] = ADC081S_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADS7866] = {
+		.channel[0] = ADS786X_CHAN(12),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADS7867] = {
+		.channel[0] = ADS786X_CHAN(10),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_ADS7868] = {
+		.channel[0] = ADS786X_CHAN(8),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+	},
+	[ID_LTC2314_14] = {
+		.channel[0] = AD7940_CHAN(14),
+		.channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1),
+		.has_vref = true,
+	},
+};
+
+static const struct iio_info ad7476_info = {
+	.read_raw = &ad7476_read_raw,
+};
+
+static void ad7476_reg_disable(void *data)
+{
+	struct regulator *reg = data;
+
+	regulator_disable(reg);
+}
+
+static int ad7476_probe(struct spi_device *spi)
+{
+	struct ad7476_state *st;
+	struct iio_dev *indio_dev;
+	struct regulator *reg;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->chip_info =
+		&ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+	reg = devm_regulator_get(&spi->dev, "vcc");
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	ret = regulator_enable(reg);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(&spi->dev, ad7476_reg_disable, reg);
+	if (ret)
+		return ret;
+
+	/* Either vcc or vref (below) as appropriate */
+	if (!st->chip_info->int_vref_uv)
+		st->ref_reg = reg;
+
+	if (st->chip_info->has_vref) {
+
+		/* If a device has an internal reference vref is optional */
+		if (st->chip_info->int_vref_uv) {
+			reg = devm_regulator_get_optional(&spi->dev, "vref");
+			if (IS_ERR(reg) && (PTR_ERR(reg) != -ENODEV))
+				return PTR_ERR(reg);
+		} else {
+			reg = devm_regulator_get(&spi->dev, "vref");
+			if (IS_ERR(reg))
+				return PTR_ERR(reg);
+		}
+
+		if (!IS_ERR(reg)) {
+			ret = regulator_enable(reg);
+			if (ret)
+				return ret;
+
+			ret = devm_add_action_or_reset(&spi->dev,
+						       ad7476_reg_disable,
+						       reg);
+			if (ret)
+				return ret;
+			st->ref_reg = reg;
+		} else {
+			/*
+			 * Can only get here if device supports both internal
+			 * and external reference, but the regulator connected
+			 * to the external reference is not connected.
+			 * Set the reference regulator pointer to NULL to
+			 * indicate this.
+			 */
+			st->ref_reg = NULL;
+		}
+	}
+
+	if (st->chip_info->has_vdrive) {
+		ret = devm_regulator_get_enable(&spi->dev, "vdrive");
+		if (ret)
+			return ret;
+	}
+
+	st->convst_gpio = devm_gpiod_get_optional(&spi->dev,
+						  "adi,conversion-start",
+						  GPIOD_OUT_LOW);
+	if (IS_ERR(st->convst_gpio))
+		return PTR_ERR(st->convst_gpio);
+
+	st->spi = spi;
+
+	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 = 2;
+	indio_dev->info = &ad7476_info;
+
+	if (st->convst_gpio)
+		indio_dev->channels = st->chip_info->convst_channel;
+	/* Setup default message */
+
+	st->xfer.rx_buf = &st->data;
+	st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8;
+
+	spi_message_init(&st->msg);
+	spi_message_add_tail(&st->xfer, &st->msg);
+
+	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,
+					      &ad7476_trigger_handler, NULL);
+	if (ret)
+		return ret;
+
+	if (st->chip_info->reset)
+		st->chip_info->reset(st);
+
+	return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id ad7476_id[] = {
+	{"ad7091", ID_AD7091},
+	{"ad7091r", ID_AD7091R},
+	{"ad7273", ID_AD7273},
+	{"ad7274", ID_AD7274},
+	{"ad7276", ID_AD7276},
+	{"ad7277", ID_AD7277},
+	{"ad7278", ID_AD7278},
+	{"ad7466", ID_AD7466},
+	{"ad7467", ID_AD7467},
+	{"ad7468", ID_AD7468},
+	{"ad7475", ID_AD7475},
+	{"ad7476", ID_AD7466},
+	{"ad7476a", ID_AD7466},
+	{"ad7477", ID_AD7467},
+	{"ad7477a", ID_AD7467},
+	{"ad7478", ID_AD7468},
+	{"ad7478a", ID_AD7468},
+	{"ad7495", ID_AD7495},
+	{"ad7910", ID_AD7467},
+	{"ad7920", ID_AD7466},
+	{"ad7940", ID_AD7940},
+	{"adc081s", ID_ADC081S},
+	{"adc101s", ID_ADC101S},
+	{"adc121s", ID_ADC121S},
+	{"ads7866", ID_ADS7866},
+	{"ads7867", ID_ADS7867},
+	{"ads7868", ID_ADS7868},
+	{"ltc2314-14", ID_LTC2314_14},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ad7476_id);
+
+static struct spi_driver ad7476_driver = {
+	.driver = {
+		.name	= "ad7476",
+	},
+	.probe		= ad7476_probe,
+	.id_table	= ad7476_id,
+};
+module_spi_driver(ad7476_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD7476 and similar 1-channel ADCs");
+MODULE_LICENSE("GPL v2");