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Message-ID: <c189c25b1c46f406c3f7942e5ac4cdb0b964ee52.1764708608.git.marcelo.schmitt@analog.com>
Date: Tue, 2 Dec 2025 17:55:21 -0300
From: Marcelo Schmitt <marcelo.schmitt@...log.com>
To: <linux-iio@...r.kernel.org>, <devicetree@...r.kernel.org>,
        <linux-doc@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC: <jic23@...nel.org>, <nuno.sa@...log.com>, <dlechner@...libre.com>,
        <andy@...nel.org>, <Michael.Hennerich@...log.com>, <robh@...nel.org>,
        <krzk+dt@...nel.org>, <conor+dt@...nel.org>, <corbet@....net>,
        <marcelo.schmitt1@...il.com>
Subject: [PATCH v3 2/3] iio: adc: Initial support for AD4134

AD4134 is a 24-bit, 4-channel, simultaneous sampling, precision
analog-to-digital converter (ADC). The device can be managed through SPI or
direct control of pin logical levels (pin control mode). The AD4134 design
also features a dedicated bus for ADC sample data output. Though, this
initial driver for AD4134 only supports usual SPI connections.

Add basic support for AD4134 that enables single-shot ADC sample read.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@...log.com>
---
Change log v2 -> v3:
- Dropped leftover dev field from struct ad4134_state.
- Inverted if condition and reduced indentation in ad4134_regulator_setup().
- Use (MICRO / MILLI) for microvolt/milivolt conversion.
- Handled clock deferred probe cases.

I tried using the reset-gpio driver to handle AD4134 reset GPIO. I had changed
the device tree to set a reset-controller node and had referenced that from the
ADC node. I also updated the ad4134 driver to use a reset controller to handle
its reset GPIO. Though, after those changes, the AD4134 driver would defer
device initialization forever because it missed a reset-controller. To make the
reset-gpio driver probe and instantiate a reset controller, it would take a
platform device to be set within a machine-specific, hardcoded platform data.
AD4134 is not bound to any specific platform, so it doesn't make much sense to
have a reset-gpio platform device for that. Thanks for mentioning reset-gpio. It
was interesting looking into the reset-gpio driver and the reset framework. It
looks cool. But I don't think the reset-gpio driver suits the AD4134 reset use
case.

The updated routine to get the external clock source now copes with deferred
device probing. I still think the v1 way of getting the clock looked better, but
if the way it is done in v3 looks better for maintainers and reviewers, I'll
acknowledge and keep that.

For reference, v1 clock initialization was
	ret = device_property_match_property_string(dev, "clock-names",
						    ad4134_clk_sel,
						    ARRAY_SIZE(ad4134_clk_sel));
	if (ret < 0)
		return dev_err_probe(dev, ret, "failed to find external clock\n");

	sys_clk = devm_clk_get_enabled(dev, ad4134_clk_sel[ret]);
	if (IS_ERR(sys_clk))
		return dev_err_probe(dev, PTR_ERR(sys_clk),
				     "failed to get %s external clock\n",
				     ad4134_clk_sel[ret]);

 MAINTAINERS              |   1 +
 drivers/iio/adc/Kconfig  |  11 +
 drivers/iio/adc/Makefile |   1 +
 drivers/iio/adc/ad4134.c | 503 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 516 insertions(+)
 create mode 100644 drivers/iio/adc/ad4134.c

diff --git a/MAINTAINERS b/MAINTAINERS
index b9029c4055e3..a1541cf3967b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1455,6 +1455,7 @@ L:	linux-iio@...r.kernel.org
 S:	Supported
 W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml
+F:	drivers/iio/adc/ad4134.c
 
 ANALOG DEVICES INC AD4170-4 DRIVER
 M:	Marcelo Schmitt <marcelo.schmitt@...log.com>
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 58da8255525e..e711a146bd23 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -99,6 +99,17 @@ config AD4130
 	  To compile this driver as a module, choose M here: the module will be
 	  called ad4130.
 
+config AD4134
+	tristate "Analog Device AD4134 ADC Driver"
+	depends on SPI
+	select REGMAP_SPI
+	select CRC8
+	help
+	  Say yes here to build support for Analog Devices AD4134 SPI analog to
+	  digital converters (ADC).
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called ad4134_spi.
 
 config AD4170_4
 	tristate "Analog Device AD4170-4 ADC Driver"
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 7cc8f9a12f76..4f834b56e0f0 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_AD4000) += ad4000.o
 obj-$(CONFIG_AD4030) += ad4030.o
 obj-$(CONFIG_AD4080) += ad4080.o
 obj-$(CONFIG_AD4130) += ad4130.o
+obj-$(CONFIG_AD4134) += ad4134.o
 obj-$(CONFIG_AD4170_4) += ad4170-4.o
 obj-$(CONFIG_AD4695) += ad4695.o
 obj-$(CONFIG_AD4851) += ad4851.o
diff --git a/drivers/iio/adc/ad4134.c b/drivers/iio/adc/ad4134.c
new file mode 100644
index 000000000000..7158eefcd877
--- /dev/null
+++ b/drivers/iio/adc/ad4134.c
@@ -0,0 +1,503 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2025 Analog Devices, Inc.
+ * Author: Marcelo Schmitt <marcelo.schmitt@...log.com>
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/types.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/time.h>
+#include <linux/types.h>
+#include <linux/unaligned.h>
+#include <linux/units.h>
+
+#define AD4134_RESET_TIME_US			(10 * USEC_PER_SEC)
+
+#define AD4134_REG_READ_MASK			BIT(7)
+#define AD4134_SPI_MAX_XFER_LEN			3
+
+#define AD4134_EXT_CLOCK_MHZ			(48 * HZ_PER_MHZ)
+
+#define AD4134_NUM_CHANNELS			4
+#define AD4134_CHAN_PRECISION_BITS		24
+
+#define AD4134_IFACE_CONFIG_A_REG		0x00
+#define AD4134_IFACE_CONFIG_B_REG		0x01
+#define AD4134_IFACE_CONFIG_B_SINGLE_INSTR	BIT(7)
+
+#define AD4134_DEVICE_CONFIG_REG		0x02
+#define AD4134_DEVICE_CONFIG_POWER_MODE_MASK	BIT(0)
+#define AD4134_POWER_MODE_HIGH_PERF		0x1
+
+#define AD4134_SILICON_REV_REG			0x07
+#define AD4134_SCRATCH_PAD_REG			0x0A
+#define AD4134_STREAM_MODE_REG			0x0E
+#define AD4134_SDO_PIN_SRC_SEL_REG		0x10
+#define AD4134_SDO_PIN_SRC_SEL_SDO_SEL_MASK	BIT(2)
+
+#define AD4134_DATA_PACKET_CONFIG_REG		0x11
+#define AD4134_DATA_PACKET_CONFIG_FRAME_MASK	GENMASK(5, 4)
+#define AD4134_DATA_PACKET_24BIT_FRAME		0x2
+
+#define AD4134_DIG_IF_CFG_REG			0x12
+#define AD4134_DIF_IF_CFG_FORMAT_MASK		GENMASK(1, 0)
+#define AD4134_DATA_FORMAT_SINGLE_CH_MODE	0x0
+
+#define AD4134_PW_DOWN_CTRL_REG			0x13
+#define AD4134_DEVICE_STATUS_REG		0x15
+#define AD4134_ODR_VAL_INT_LSB_REG		0x16
+#define AD4134_CH3_OFFSET_MSB_REG		0x3E
+#define AD4134_AIN_OR_ERROR_REG			0x48
+
+/*
+ * AD4134 register map ends at address 0x48 and there is no register for
+ * retrieving ADC sample data. Though, to make use of Linux regmap API both
+ * for register access and sample read, we define one virtual register for each
+ * ADC channel. AD4134_CH_VREG(x) maps a channel number to it's virtual register
+ * address while AD4134_VREG_CH(x) tells which channel given the address.
+ */
+#define AD4134_CH_VREG(x)			((x) + 0x50)
+#define AD4134_VREG_CH(x)			((x) - 0x50)
+
+#define AD4134_SPI_CRC_POLYNOM			0x07
+#define AD4134_SPI_CRC_INIT_VALUE		0xA5
+static unsigned char ad4134_spi_crc_table[CRC8_TABLE_SIZE];
+
+#define AD4134_CHANNEL(_index) {						\
+	.type = IIO_VOLTAGE,							\
+	.indexed = 1,								\
+	.channel = (_index),							\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),				\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),			\
+}
+
+static const struct iio_chan_spec ad4134_chan_set[] = {
+	AD4134_CHANNEL(0),
+	AD4134_CHANNEL(1),
+	AD4134_CHANNEL(2),
+	AD4134_CHANNEL(3),
+};
+
+struct ad4134_state {
+	struct spi_device *spi;
+	struct regmap *regmap;
+	unsigned long sys_clk_hz;
+	struct gpio_desc *odr_gpio;
+	int refin_mv;
+	/*
+	 * DMA (thus cache coherency maintenance) requires the transfer buffers
+	 * to live in their own cache lines.
+	 */
+	u8 rx_buf[AD4134_SPI_MAX_XFER_LEN] __aligned(IIO_DMA_MINALIGN);
+	u8 tx_buf[AD4134_SPI_MAX_XFER_LEN];
+};
+
+static const struct regmap_range ad4134_regmap_rd_range[] = {
+	regmap_reg_range(AD4134_IFACE_CONFIG_A_REG, AD4134_SILICON_REV_REG),
+	regmap_reg_range(AD4134_SCRATCH_PAD_REG, AD4134_PW_DOWN_CTRL_REG),
+	regmap_reg_range(AD4134_DEVICE_STATUS_REG, AD4134_AIN_OR_ERROR_REG),
+	regmap_reg_range(AD4134_CH_VREG(0), AD4134_CH_VREG(AD4134_NUM_CHANNELS)),
+};
+
+static const struct regmap_range ad4134_regmap_wr_range[] = {
+	regmap_reg_range(AD4134_IFACE_CONFIG_A_REG, AD4134_DEVICE_CONFIG_REG),
+	regmap_reg_range(AD4134_SCRATCH_PAD_REG, AD4134_SCRATCH_PAD_REG),
+	regmap_reg_range(AD4134_STREAM_MODE_REG, AD4134_PW_DOWN_CTRL_REG),
+	regmap_reg_range(AD4134_ODR_VAL_INT_LSB_REG, AD4134_CH3_OFFSET_MSB_REG),
+};
+
+static const struct regmap_access_table ad4134_regmap_rd_table = {
+	.yes_ranges = ad4134_regmap_rd_range,
+	.n_yes_ranges = ARRAY_SIZE(ad4134_regmap_rd_range),
+};
+
+static const struct regmap_access_table ad4134_regmap_wr_table = {
+	.yes_ranges = ad4134_regmap_wr_range,
+	.n_yes_ranges = ARRAY_SIZE(ad4134_regmap_wr_range),
+};
+
+static int ad4134_calc_spi_crc(u8 inst, u8 data)
+{
+	u8 buf[] = { inst, data };
+
+	return crc8(ad4134_spi_crc_table, buf, ARRAY_SIZE(buf),
+		    AD4134_SPI_CRC_INIT_VALUE);
+}
+
+static void ad4134_prepare_spi_tx_buf(u8 inst, u8 data, u8 *buf)
+{
+	buf[0] = inst;
+	buf[1] = data;
+	buf[2] = ad4134_calc_spi_crc(inst, data);
+}
+
+static int ad4134_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	struct ad4134_state *st = context;
+	struct spi_transfer xfer = {
+		.tx_buf = st->tx_buf,
+		.rx_buf = st->rx_buf,
+		.len = AD4134_SPI_MAX_XFER_LEN,
+	};
+	int ret;
+
+	ad4134_prepare_spi_tx_buf(reg, val, st->tx_buf);
+
+	ret = spi_sync_transfer(st->spi, &xfer, 1);
+	if (ret)
+		return ret;
+
+	if (st->rx_buf[2] != st->tx_buf[2])
+		dev_dbg(&st->spi->dev, "reg write CRC check failed\n");
+
+	return 0;
+}
+
+static int ad4134_data_read(struct ad4134_state *st, unsigned int reg,
+			    unsigned int *val)
+{
+	unsigned int i;
+	int ret;
+
+	/*
+	 * To be able to read data from all 4 channels through a single line, we
+	 * set DOUTx output format to 0 in the digital interface config register
+	 * (0x12). With that, data from all four channels is serialized and
+	 * output on DOUT0. During probe, we also set SDO_PIN_SRC_SEL in
+	 * DEVICE_CONFIG_1 register to duplicate DOUT0 on the SDO pin. Combined,
+	 * those configurations enable ADC data read through a conventional SPI
+	 * interface. Now we read data from all channels but keep only the bits
+	 * from the requested one.
+	 */
+	for (i = 0; i < ARRAY_SIZE(ad4134_chan_set); i++) {
+		ret = spi_write_then_read(st->spi, NULL, 0, st->rx_buf,
+					  BITS_TO_BYTES(AD4134_CHAN_PRECISION_BITS));
+		if (ret)
+			return ret;
+
+		if (i != AD4134_VREG_CH(reg))
+			continue;
+
+		*val = get_unaligned_be24(st->rx_buf);
+	}
+
+	return 0;
+}
+
+static int ad4134_register_read(struct ad4134_state *st, unsigned int reg,
+				unsigned int *val)
+{
+	struct spi_transfer xfer = {
+		.tx_buf = st->tx_buf,
+		.rx_buf = st->rx_buf,
+		.len = AD4134_SPI_MAX_XFER_LEN,
+	};
+	unsigned int inst;
+	int ret;
+
+	inst = AD4134_REG_READ_MASK | reg;
+	ad4134_prepare_spi_tx_buf(inst, 0, st->tx_buf);
+
+	ret = spi_sync_transfer(st->spi, &xfer, 1);
+	if (ret)
+		return ret;
+
+	*val = st->rx_buf[1];
+
+	/* Check CRC */
+	if (st->rx_buf[2] != st->tx_buf[2])
+		dev_dbg(&st->spi->dev, "reg read CRC check failed\n");
+
+	return 0;
+}
+
+static int ad4134_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	struct ad4134_state *st = context;
+
+	if (reg >= AD4134_CH_VREG(0))
+		return ad4134_data_read(st, reg, val);
+
+	return ad4134_register_read(st, reg, val);
+}
+
+static const struct regmap_config ad4134_regmap_config = {
+	.reg_read = ad4134_reg_read,
+	.reg_write = ad4134_reg_write,
+	.rd_table = &ad4134_regmap_rd_table,
+	.wr_table = &ad4134_regmap_wr_table,
+	.max_register = AD4134_CH_VREG(ARRAY_SIZE(ad4134_chan_set)),
+};
+
+static int ad4134_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long info)
+{
+	struct ad4134_state *st = iio_priv(indio_dev);
+	int ret;
+
+	switch (info) {
+	case IIO_CHAN_INFO_RAW:
+		gpiod_set_value_cansleep(st->odr_gpio, 1);
+		fsleep(1);
+		gpiod_set_value_cansleep(st->odr_gpio, 0);
+		ret = regmap_read(st->regmap, AD4134_CH_VREG(chan->channel), val);
+		if (ret)
+			return ret;
+
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = st->refin_mv;
+		*val2 = AD4134_CHAN_PRECISION_BITS - 1;
+
+		return IIO_VAL_FRACTIONAL_LOG2;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ad4134_debugfs_reg_access(struct iio_dev *indio_dev,
+				     unsigned int reg, unsigned int writeval,
+				     unsigned int *readval)
+{
+	struct ad4134_state *st = iio_priv(indio_dev);
+
+	if (readval)
+		return regmap_read(st->regmap, reg, readval);
+
+	return regmap_write(st->regmap, reg, writeval);
+}
+
+static int ad4134_min_io_mode_setup(struct ad4134_state *st)
+{
+	struct device *dev = &st->spi->dev;
+	int ret;
+
+	st->odr_gpio = devm_gpiod_get(dev, "odr", GPIOD_OUT_LOW);
+	if (IS_ERR(st->odr_gpio))
+		return dev_err_probe(dev, PTR_ERR(st->odr_gpio),
+				     "failed to get ODR GPIO\n");
+
+	ret = regmap_update_bits(st->regmap, AD4134_DIG_IF_CFG_REG,
+				 AD4134_DIF_IF_CFG_FORMAT_MASK,
+				 FIELD_PREP(AD4134_DIF_IF_CFG_FORMAT_MASK,
+					    AD4134_DATA_FORMAT_SINGLE_CH_MODE));
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to set single channel mode\n");
+
+	ret = regmap_set_bits(st->regmap, AD4134_SDO_PIN_SRC_SEL_REG,
+			      AD4134_SDO_PIN_SRC_SEL_SDO_SEL_MASK);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to set SDO source selection\n");
+
+	return regmap_set_bits(st->regmap, AD4134_IFACE_CONFIG_B_REG,
+			       AD4134_IFACE_CONFIG_B_SINGLE_INSTR);
+}
+
+static const struct iio_info ad4134_info = {
+	.read_raw = ad4134_read_raw,
+	.debugfs_reg_access = ad4134_debugfs_reg_access,
+};
+
+static const char * const ad4143_regulator_names[] = {
+	"avdd5", "dvdd5", "iovdd", "refin",
+	"avdd1v8", "dvdd1v8", "clkvdd",	"ldoin",
+};
+
+static int ad4134_regulator_setup(struct ad4134_state *st)
+{
+	struct device *dev = &st->spi->dev;
+	bool use_internal_ldo_regulator;
+	int ret;
+
+	/* Required regulators */
+	ret = devm_regulator_bulk_get_enable(dev, 3, ad4143_regulator_names);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to enable power supplies\n");
+
+	/* Required regulator that we need to read the voltage */
+	ret = devm_regulator_get_enable_read_voltage(dev, "refin");
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to get REFIN voltage.\n");
+
+	st->refin_mv = ret / (MICRO / MILLI);
+
+	/*
+	 * If ldoin is not provided, then avdd1v8, dvdd1v8, and clkvdd are
+	 * required.
+	 */
+	ret = devm_regulator_get_enable_optional(dev, "ldoin");
+	if (ret < 0 && ret != -ENODEV)
+		return dev_err_probe(dev, ret, "failed to enable ldoin supply\n");
+
+	use_internal_ldo_regulator = ret == 0;
+
+	if (use_internal_ldo_regulator)
+		return 0;
+
+	ret = devm_regulator_get_enable(dev, "avdd1v8");
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to enable avdd1v8 supply\n");
+
+	ret = devm_regulator_get_enable(dev, "dvdd1v8");
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to enable dvdd1v8 supply\n");
+
+	ret = devm_regulator_get_enable(dev, "clkvdd");
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to enable clkvdd supply\n");
+
+	return 0;
+}
+
+static int ad4134_clock_select(struct ad4134_state *st)
+{
+	struct device *dev = &st->spi->dev;
+	struct clk *sys_clk;
+
+	/*
+	 * AD4134 requires one external clock source and only one external clock
+	 * source can be provided at a time. Try get a crystal provided clock.
+	 * If that fails, try to get a CMOS clock.
+	 */
+	sys_clk = devm_clk_get_optional_enabled(dev, "xtal1-xtal2");
+	if (IS_ERR_OR_NULL(sys_clk)) {
+		if (PTR_ERR(sys_clk) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		/* Try the CMOS clock */
+		sys_clk = devm_clk_get_enabled(dev, "clkin");
+		if (IS_ERR(sys_clk)) {
+			if (PTR_ERR(sys_clk) == -EPROBE_DEFER)
+				return -EPROBE_DEFER;
+
+			return dev_err_probe(dev, PTR_ERR(sys_clk),
+					     "failed to get external clock\n");
+		}
+	}
+
+	st->sys_clk_hz = clk_get_rate(sys_clk);
+	if (st->sys_clk_hz != AD4134_EXT_CLOCK_MHZ)
+		dev_warn(dev, "invalid external clock frequency %lu\n",
+			 st->sys_clk_hz);
+
+	return 0;
+}
+
+static int ad4134_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct gpio_desc *reset_gpio;
+	struct iio_dev *indio_dev;
+	struct ad4134_state *st;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->spi = spi;
+
+	indio_dev->name = "ad4134";
+	indio_dev->channels = ad4134_chan_set;
+	indio_dev->num_channels = ARRAY_SIZE(ad4134_chan_set);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &ad4134_info;
+
+	ret = ad4134_regulator_setup(st);
+	if (ret)
+		return ret;
+
+	ret = ad4134_clock_select(st);
+	if (ret)
+		return ret;
+
+	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(reset_gpio),
+				     "failed to find reset GPIO\n");
+
+	if (reset_gpio) {
+		fsleep(AD4134_RESET_TIME_US);
+		gpiod_set_value_cansleep(reset_gpio, 0);
+	}
+
+	crc8_populate_msb(ad4134_spi_crc_table, AD4134_SPI_CRC_POLYNOM);
+
+	st->regmap = devm_regmap_init(dev, NULL, st, &ad4134_regmap_config);
+	if (IS_ERR(st->regmap))
+		return dev_err_probe(dev, PTR_ERR(st->regmap),
+				     "failed to initialize regmap");
+
+	ret = ad4134_min_io_mode_setup(st);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to setup minimum I/O mode\n");
+
+	/* Bump precision to 24-bit */
+	ret = regmap_update_bits(st->regmap, AD4134_DATA_PACKET_CONFIG_REG,
+				 AD4134_DATA_PACKET_CONFIG_FRAME_MASK,
+				 FIELD_PREP(AD4134_DATA_PACKET_CONFIG_FRAME_MASK,
+					    AD4134_DATA_PACKET_24BIT_FRAME));
+	if (ret)
+		return ret;
+
+	/* Set high performance power mode */
+	ret = regmap_update_bits(st->regmap, AD4134_DEVICE_CONFIG_REG,
+				 AD4134_DEVICE_CONFIG_POWER_MODE_MASK,
+				 FIELD_PREP(AD4134_DEVICE_CONFIG_POWER_MODE_MASK,
+					    AD4134_POWER_MODE_HIGH_PERF));
+	if (ret)
+		return ret;
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct spi_device_id ad4134_id[] = {
+	{ "ad4134" },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ad4134_id);
+
+static const struct of_device_id ad4134_of_match[] = {
+	{ .compatible = "adi,ad4134" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ad4134_of_match);
+
+static struct spi_driver ad4134_driver = {
+	.driver = {
+		.name = "ad4134",
+		.of_match_table = ad4134_of_match,
+	},
+	.probe = ad4134_probe,
+	.id_table = ad4134_id,
+};
+module_spi_driver(ad4134_driver);
+
+MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@...log.com>");
+MODULE_DESCRIPTION("Analog Devices AD4134 SPI driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("IIO_AD4134");
-- 
2.51.0


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