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iio: adc: Add support for AD4000
Add support for AD4000 series of low noise, low power, high speed, successive approximation register (SAR) ADCs. Reviewed-by: Nuno Sa <nuno.sa@analog.com> Reviewed-by: David Lechner <dlechner@baylibre.com> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com> Link: https://patch.msgid.link/356109ac61182f16f2379d5d0cadccfe017f505b.1720810545.git.marcelo.schmitt@analog.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
parent
b71fdd65ca
commit
938fd562b9
@ -1220,6 +1220,7 @@ L: linux-iio@vger.kernel.org
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S: Supported
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W: https://ez.analog.com/linux-software-drivers
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F: Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
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F: drivers/iio/adc/ad4000.c
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ANALOG DEVICES INC AD4130 DRIVER
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M: Cosmin Tanislav <cosmin.tanislav@analog.com>
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@ -21,6 +21,18 @@ config AD_SIGMA_DELTA
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select IIO_BUFFER
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select IIO_TRIGGERED_BUFFER
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config AD4000
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tristate "Analog Devices AD4000 ADC Driver"
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depends on SPI
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select IIO_BUFFER
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select IIO_TRIGGERED_BUFFER
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help
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Say yes here to build support for Analog Devices AD4000 high speed
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SPI analog to digital converters (ADC).
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To compile this driver as a module, choose M here: the module will be
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called ad4000.
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config AD4130
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tristate "Analog Device AD4130 ADC Driver"
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depends on SPI
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@ -6,6 +6,7 @@
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# When adding new entries keep the list in alphabetical order
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obj-$(CONFIG_AB8500_GPADC) += ab8500-gpadc.o
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obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
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obj-$(CONFIG_AD4000) += ad4000.o
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obj-$(CONFIG_AD4130) += ad4130.o
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obj-$(CONFIG_AD4695) += ad4695.o
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obj-$(CONFIG_AD7091R) += ad7091r-base.o
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drivers/iio/adc/ad4000.c
Normal file
722
drivers/iio/adc/ad4000.c
Normal file
@ -0,0 +1,722 @@
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// SPDX-License-Identifier: GPL-2.0+
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/*
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* AD4000 SPI ADC driver
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*
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* Copyright 2024 Analog Devices Inc.
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*/
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#include <linux/bits.h>
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#include <linux/bitfield.h>
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#include <linux/byteorder/generic.h>
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#include <linux/cleanup.h>
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/math.h>
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#include <linux/module.h>
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#include <linux/mod_devicetable.h>
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#include <linux/gpio/consumer.h>
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#include <linux/regulator/consumer.h>
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#include <linux/spi/spi.h>
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#include <linux/units.h>
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#include <linux/util_macros.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/triggered_buffer.h>
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#include <linux/iio/trigger_consumer.h>
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#define AD4000_READ_COMMAND 0x54
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#define AD4000_WRITE_COMMAND 0x14
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#define AD4000_CONFIG_REG_DEFAULT 0xE1
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/* AD4000 Configuration Register programmable bits */
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#define AD4000_CFG_SPAN_COMP BIT(3) /* Input span compression */
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#define AD4000_CFG_HIGHZ BIT(2) /* High impedance mode */
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#define AD4000_SCALE_OPTIONS 2
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#define AD4000_TQUIET1_NS 190
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#define AD4000_TQUIET2_NS 60
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#define AD4000_TCONV_NS 320
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#define __AD4000_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access) \
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{ \
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.type = IIO_VOLTAGE, \
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.indexed = 1, \
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.differential = 1, \
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.channel = 0, \
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.channel2 = 1, \
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.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
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BIT(IIO_CHAN_INFO_SCALE), \
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.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\
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.scan_type = { \
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.sign = _sign, \
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.realbits = _real_bits, \
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.storagebits = _storage_bits, \
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.shift = _storage_bits - _real_bits, \
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.endianness = IIO_BE, \
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}, \
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}
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#define AD4000_DIFF_CHANNEL(_sign, _real_bits, _reg_access) \
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__AD4000_DIFF_CHANNEL((_sign), (_real_bits), \
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((_real_bits) > 16 ? 32 : 16), (_reg_access))
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#define __AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access)\
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{ \
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.type = IIO_VOLTAGE, \
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.indexed = 1, \
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.channel = 0, \
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.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
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BIT(IIO_CHAN_INFO_SCALE) | \
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BIT(IIO_CHAN_INFO_OFFSET), \
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.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\
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.scan_type = { \
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.sign = _sign, \
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.realbits = _real_bits, \
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.storagebits = _storage_bits, \
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.shift = _storage_bits - _real_bits, \
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.endianness = IIO_BE, \
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}, \
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}
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#define AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _reg_access) \
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__AD4000_PSEUDO_DIFF_CHANNEL((_sign), (_real_bits), \
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((_real_bits) > 16 ? 32 : 16), (_reg_access))
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static const char * const ad4000_power_supplies[] = {
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"vdd", "vio"
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};
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enum ad4000_sdi {
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AD4000_SDI_MOSI,
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AD4000_SDI_VIO,
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AD4000_SDI_CS,
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AD4000_SDI_GND,
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};
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/* maps adi,sdi-pin property value to enum */
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static const char * const ad4000_sdi_pin[] = {
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[AD4000_SDI_MOSI] = "sdi",
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[AD4000_SDI_VIO] = "high",
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[AD4000_SDI_CS] = "cs",
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[AD4000_SDI_GND] = "low",
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};
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/* Gains stored as fractions of 1000 so they can be expressed by integers. */
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static const int ad4000_gains[] = {
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454, 909, 1000, 1900,
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};
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struct ad4000_chip_info {
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const char *dev_name;
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struct iio_chan_spec chan_spec;
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struct iio_chan_spec reg_access_chan_spec;
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bool has_hardware_gain;
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};
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static const struct ad4000_chip_info ad4000_chip_info = {
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.dev_name = "ad4000",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
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};
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static const struct ad4000_chip_info ad4001_chip_info = {
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.dev_name = "ad4001",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
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};
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static const struct ad4000_chip_info ad4002_chip_info = {
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.dev_name = "ad4002",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
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};
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static const struct ad4000_chip_info ad4003_chip_info = {
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.dev_name = "ad4003",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
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};
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static const struct ad4000_chip_info ad4004_chip_info = {
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.dev_name = "ad4004",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
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};
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static const struct ad4000_chip_info ad4005_chip_info = {
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.dev_name = "ad4005",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
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};
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static const struct ad4000_chip_info ad4006_chip_info = {
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.dev_name = "ad4006",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
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};
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static const struct ad4000_chip_info ad4007_chip_info = {
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.dev_name = "ad4007",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
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};
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static const struct ad4000_chip_info ad4008_chip_info = {
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.dev_name = "ad4008",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),
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};
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static const struct ad4000_chip_info ad4010_chip_info = {
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.dev_name = "ad4010",
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.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),
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.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),
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};
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static const struct ad4000_chip_info ad4011_chip_info = {
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.dev_name = "ad4011",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
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};
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static const struct ad4000_chip_info ad4020_chip_info = {
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.dev_name = "ad4020",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
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};
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static const struct ad4000_chip_info ad4021_chip_info = {
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.dev_name = "ad4021",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
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};
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static const struct ad4000_chip_info ad4022_chip_info = {
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.dev_name = "ad4022",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),
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};
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static const struct ad4000_chip_info adaq4001_chip_info = {
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.dev_name = "adaq4001",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),
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.has_hardware_gain = true,
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};
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static const struct ad4000_chip_info adaq4003_chip_info = {
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.dev_name = "adaq4003",
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.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),
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.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),
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.has_hardware_gain = true,
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};
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struct ad4000_state {
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struct spi_device *spi;
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struct gpio_desc *cnv_gpio;
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struct spi_transfer xfers[2];
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struct spi_message msg;
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struct mutex lock; /* Protect read modify write cycle */
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int vref_mv;
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enum ad4000_sdi sdi_pin;
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bool span_comp;
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u16 gain_milli;
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int scale_tbl[AD4000_SCALE_OPTIONS][2];
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/*
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* DMA (thus cache coherency maintenance) requires the transfer buffers
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* to live in their own cache lines.
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*/
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struct {
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union {
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__be16 sample_buf16;
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__be32 sample_buf32;
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} data;
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s64 timestamp __aligned(8);
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} scan __aligned(IIO_DMA_MINALIGN);
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u8 tx_buf[2];
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u8 rx_buf[2];
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};
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static void ad4000_fill_scale_tbl(struct ad4000_state *st,
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struct iio_chan_spec const *chan)
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{
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int val, tmp0, tmp1;
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int scale_bits;
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u64 tmp2;
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/*
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* ADCs that output two's complement code have one less bit to express
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* voltage magnitude.
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*/
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if (chan->scan_type.sign == 's')
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scale_bits = chan->scan_type.realbits - 1;
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else
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scale_bits = chan->scan_type.realbits;
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/*
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* The gain is stored as a fraction of 1000 and, as we need to
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* divide vref_mv by the gain, we invert the gain/1000 fraction.
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* Also multiply by an extra MILLI to preserve precision.
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* Thus, we have MILLI * MILLI equals MICRO as fraction numerator.
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*/
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val = mult_frac(st->vref_mv, MICRO, st->gain_milli);
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/* Would multiply by NANO here but we multiplied by extra MILLI */
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tmp2 = shift_right((u64)val * MICRO, scale_bits);
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tmp0 = div_s64_rem(tmp2, NANO, &tmp1);
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/* Store scale for when span compression is disabled */
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st->scale_tbl[0][0] = tmp0; /* Integer part */
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st->scale_tbl[0][1] = abs(tmp1); /* Fractional part */
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/* Store scale for when span compression is enabled */
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st->scale_tbl[1][0] = tmp0;
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/* The integer part is always zero so don't bother to divide it. */
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if (chan->differential)
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st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 4, 5);
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else
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st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 9, 10);
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}
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static int ad4000_write_reg(struct ad4000_state *st, uint8_t val)
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{
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st->tx_buf[0] = AD4000_WRITE_COMMAND;
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st->tx_buf[1] = val;
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return spi_write(st->spi, st->tx_buf, ARRAY_SIZE(st->tx_buf));
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}
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static int ad4000_read_reg(struct ad4000_state *st, unsigned int *val)
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{
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struct spi_transfer t = {
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.tx_buf = st->tx_buf,
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.rx_buf = st->rx_buf,
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.len = 2,
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};
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int ret;
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st->tx_buf[0] = AD4000_READ_COMMAND;
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ret = spi_sync_transfer(st->spi, &t, 1);
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if (ret < 0)
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return ret;
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*val = st->rx_buf[1];
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return ret;
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}
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static int ad4000_convert_and_acquire(struct ad4000_state *st)
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{
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int ret;
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/*
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* In 4-wire mode, the CNV line is held high for the entire conversion
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* and acquisition process. In other modes, the CNV GPIO is optional
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* and, if provided, replaces controller CS. If CNV GPIO is not defined
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* gpiod_set_value_cansleep() has no effect.
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*/
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gpiod_set_value_cansleep(st->cnv_gpio, 1);
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ret = spi_sync(st->spi, &st->msg);
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gpiod_set_value_cansleep(st->cnv_gpio, 0);
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return ret;
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}
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static int ad4000_single_conversion(struct iio_dev *indio_dev,
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const struct iio_chan_spec *chan, int *val)
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{
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struct ad4000_state *st = iio_priv(indio_dev);
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u32 sample;
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int ret;
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ret = ad4000_convert_and_acquire(st);
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if (ret < 0)
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return ret;
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if (chan->scan_type.storagebits > 16)
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sample = be32_to_cpu(st->scan.data.sample_buf32);
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else
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sample = be16_to_cpu(st->scan.data.sample_buf16);
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sample >>= chan->scan_type.shift;
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if (chan->scan_type.sign == 's')
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*val = sign_extend32(sample, chan->scan_type.realbits - 1);
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return IIO_VAL_INT;
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}
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static int ad4000_read_raw(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan, int *val,
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int *val2, long info)
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{
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struct ad4000_state *st = iio_priv(indio_dev);
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switch (info) {
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case IIO_CHAN_INFO_RAW:
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iio_device_claim_direct_scoped(return -EBUSY, indio_dev)
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return ad4000_single_conversion(indio_dev, chan, val);
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unreachable();
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case IIO_CHAN_INFO_SCALE:
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*val = st->scale_tbl[st->span_comp][0];
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*val2 = st->scale_tbl[st->span_comp][1];
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return IIO_VAL_INT_PLUS_NANO;
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case IIO_CHAN_INFO_OFFSET:
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*val = 0;
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if (st->span_comp)
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*val = mult_frac(st->vref_mv, 1, 10);
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return IIO_VAL_INT;
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default:
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return -EINVAL;
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}
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}
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static int ad4000_read_avail(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan,
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const int **vals, int *type, int *length,
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long info)
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{
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struct ad4000_state *st = iio_priv(indio_dev);
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switch (info) {
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case IIO_CHAN_INFO_SCALE:
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*vals = (int *)st->scale_tbl;
|
||||
*length = AD4000_SCALE_OPTIONS * 2;
|
||||
*type = IIO_VAL_INT_PLUS_NANO;
|
||||
return IIO_AVAIL_LIST;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static int ad4000_write_raw_get_fmt(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan, long mask)
|
||||
{
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
return IIO_VAL_INT_PLUS_NANO;
|
||||
default:
|
||||
return IIO_VAL_INT_PLUS_MICRO;
|
||||
}
|
||||
}
|
||||
|
||||
static int ad4000_write_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan, int val, int val2,
|
||||
long mask)
|
||||
{
|
||||
struct ad4000_state *st = iio_priv(indio_dev);
|
||||
unsigned int reg_val;
|
||||
bool span_comp_en;
|
||||
int ret;
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
|
||||
guard(mutex)(&st->lock);
|
||||
|
||||
ret = ad4000_read_reg(st, ®_val);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
span_comp_en = val2 == st->scale_tbl[1][1];
|
||||
reg_val &= ~AD4000_CFG_SPAN_COMP;
|
||||
reg_val |= FIELD_PREP(AD4000_CFG_SPAN_COMP, span_comp_en);
|
||||
|
||||
ret = ad4000_write_reg(st, reg_val);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
st->span_comp = span_comp_en;
|
||||
return 0;
|
||||
}
|
||||
unreachable();
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static irqreturn_t ad4000_trigger_handler(int irq, void *p)
|
||||
{
|
||||
struct iio_poll_func *pf = p;
|
||||
struct iio_dev *indio_dev = pf->indio_dev;
|
||||
struct ad4000_state *st = iio_priv(indio_dev);
|
||||
int ret;
|
||||
|
||||
ret = ad4000_convert_and_acquire(st);
|
||||
if (ret < 0)
|
||||
goto err_out;
|
||||
|
||||
iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, pf->timestamp);
|
||||
|
||||
err_out:
|
||||
iio_trigger_notify_done(indio_dev->trig);
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static const struct iio_info ad4000_reg_access_info = {
|
||||
.read_raw = &ad4000_read_raw,
|
||||
.read_avail = &ad4000_read_avail,
|
||||
.write_raw = &ad4000_write_raw,
|
||||
.write_raw_get_fmt = &ad4000_write_raw_get_fmt,
|
||||
};
|
||||
|
||||
static const struct iio_info ad4000_info = {
|
||||
.read_raw = &ad4000_read_raw,
|
||||
};
|
||||
|
||||
/*
|
||||
* This executes a data sample transfer for when the device connections are
|
||||
* in "3-wire" mode, selected when the adi,sdi-pin device tree property is
|
||||
* absent or set to "high". In this connection mode, the ADC SDI pin is
|
||||
* connected to MOSI or to VIO and ADC CNV pin is connected either to a SPI
|
||||
* controller CS or to a GPIO.
|
||||
* AD4000 series of devices initiate conversions on the rising edge of CNV pin.
|
||||
*
|
||||
* If the CNV pin is connected to an SPI controller CS line (which is by default
|
||||
* active low), the ADC readings would have a latency (delay) of one read.
|
||||
* Moreover, since we also do ADC sampling for filling the buffer on triggered
|
||||
* buffer mode, the timestamps of buffer readings would be disarranged.
|
||||
* To prevent the read latency and reduce the time discrepancy between the
|
||||
* sample read request and the time of actual sampling by the ADC, do a
|
||||
* preparatory transfer to pulse the CS/CNV line.
|
||||
*/
|
||||
static int ad4000_prepare_3wire_mode_message(struct ad4000_state *st,
|
||||
const struct iio_chan_spec *chan)
|
||||
{
|
||||
unsigned int cnv_pulse_time = AD4000_TCONV_NS;
|
||||
struct spi_transfer *xfers = st->xfers;
|
||||
|
||||
xfers[0].cs_change = 1;
|
||||
xfers[0].cs_change_delay.value = cnv_pulse_time;
|
||||
xfers[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
|
||||
|
||||
xfers[1].rx_buf = &st->scan.data;
|
||||
xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);
|
||||
xfers[1].delay.value = AD4000_TQUIET2_NS;
|
||||
xfers[1].delay.unit = SPI_DELAY_UNIT_NSECS;
|
||||
|
||||
spi_message_init_with_transfers(&st->msg, st->xfers, 2);
|
||||
|
||||
return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);
|
||||
}
|
||||
|
||||
/*
|
||||
* This executes a data sample transfer for when the device connections are
|
||||
* in "4-wire" mode, selected when the adi,sdi-pin device tree property is
|
||||
* set to "cs". In this connection mode, the controller CS pin is connected to
|
||||
* ADC SDI pin and a GPIO is connected to ADC CNV pin.
|
||||
* The GPIO connected to ADC CNV pin is set outside of the SPI transfer.
|
||||
*/
|
||||
static int ad4000_prepare_4wire_mode_message(struct ad4000_state *st,
|
||||
const struct iio_chan_spec *chan)
|
||||
{
|
||||
unsigned int cnv_to_sdi_time = AD4000_TCONV_NS;
|
||||
struct spi_transfer *xfers = st->xfers;
|
||||
|
||||
/*
|
||||
* Dummy transfer to cause enough delay between CNV going high and SDI
|
||||
* going low.
|
||||
*/
|
||||
xfers[0].cs_off = 1;
|
||||
xfers[0].delay.value = cnv_to_sdi_time;
|
||||
xfers[0].delay.unit = SPI_DELAY_UNIT_NSECS;
|
||||
|
||||
xfers[1].rx_buf = &st->scan.data;
|
||||
xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);
|
||||
|
||||
spi_message_init_with_transfers(&st->msg, st->xfers, 2);
|
||||
|
||||
return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);
|
||||
}
|
||||
|
||||
static int ad4000_config(struct ad4000_state *st)
|
||||
{
|
||||
unsigned int reg_val = AD4000_CONFIG_REG_DEFAULT;
|
||||
|
||||
if (device_property_present(&st->spi->dev, "adi,high-z-input"))
|
||||
reg_val |= FIELD_PREP(AD4000_CFG_HIGHZ, 1);
|
||||
|
||||
return ad4000_write_reg(st, reg_val);
|
||||
}
|
||||
|
||||
static int ad4000_probe(struct spi_device *spi)
|
||||
{
|
||||
const struct ad4000_chip_info *chip;
|
||||
struct device *dev = &spi->dev;
|
||||
struct iio_dev *indio_dev;
|
||||
struct ad4000_state *st;
|
||||
int gain_idx, ret;
|
||||
|
||||
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
|
||||
if (!indio_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
chip = spi_get_device_match_data(spi);
|
||||
if (!chip)
|
||||
return -EINVAL;
|
||||
|
||||
st = iio_priv(indio_dev);
|
||||
st->spi = spi;
|
||||
|
||||
ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ad4000_power_supplies),
|
||||
ad4000_power_supplies);
|
||||
if (ret)
|
||||
return dev_err_probe(dev, ret, "Failed to enable power supplies\n");
|
||||
|
||||
ret = devm_regulator_get_enable_read_voltage(dev, "ref");
|
||||
if (ret < 0)
|
||||
return dev_err_probe(dev, ret,
|
||||
"Failed to get ref regulator reference\n");
|
||||
st->vref_mv = ret / 1000;
|
||||
|
||||
st->cnv_gpio = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_HIGH);
|
||||
if (IS_ERR(st->cnv_gpio))
|
||||
return dev_err_probe(dev, PTR_ERR(st->cnv_gpio),
|
||||
"Failed to get CNV GPIO");
|
||||
|
||||
ret = device_property_match_property_string(dev, "adi,sdi-pin",
|
||||
ad4000_sdi_pin,
|
||||
ARRAY_SIZE(ad4000_sdi_pin));
|
||||
if (ret < 0 && ret != -EINVAL)
|
||||
return dev_err_probe(dev, ret,
|
||||
"getting adi,sdi-pin property failed\n");
|
||||
|
||||
/* Default to usual SPI connections if pin properties are not present */
|
||||
st->sdi_pin = ret == -EINVAL ? AD4000_SDI_MOSI : ret;
|
||||
switch (st->sdi_pin) {
|
||||
case AD4000_SDI_MOSI:
|
||||
indio_dev->info = &ad4000_reg_access_info;
|
||||
indio_dev->channels = &chip->reg_access_chan_spec;
|
||||
|
||||
/*
|
||||
* In "3-wire mode", the ADC SDI line must be kept high when
|
||||
* data is not being clocked out of the controller.
|
||||
* Request the SPI controller to make MOSI idle high.
|
||||
*/
|
||||
spi->mode |= SPI_MOSI_IDLE_HIGH;
|
||||
ret = spi_setup(spi);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = ad4000_config(st);
|
||||
if (ret < 0)
|
||||
return dev_err_probe(dev, ret, "Failed to config device\n");
|
||||
|
||||
break;
|
||||
case AD4000_SDI_VIO:
|
||||
indio_dev->info = &ad4000_info;
|
||||
indio_dev->channels = &chip->chan_spec;
|
||||
ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
break;
|
||||
case AD4000_SDI_CS:
|
||||
indio_dev->info = &ad4000_info;
|
||||
indio_dev->channels = &chip->chan_spec;
|
||||
ret = ad4000_prepare_4wire_mode_message(st, indio_dev->channels);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
break;
|
||||
case AD4000_SDI_GND:
|
||||
return dev_err_probe(dev, -EPROTONOSUPPORT,
|
||||
"Unsupported connection mode\n");
|
||||
|
||||
default:
|
||||
return dev_err_probe(dev, -EINVAL, "Unrecognized connection mode\n");
|
||||
}
|
||||
|
||||
indio_dev->name = chip->dev_name;
|
||||
indio_dev->num_channels = 1;
|
||||
|
||||
devm_mutex_init(dev, &st->lock);
|
||||
|
||||
st->gain_milli = 1000;
|
||||
if (chip->has_hardware_gain) {
|
||||
ret = device_property_read_u16(dev, "adi,gain-milli",
|
||||
&st->gain_milli);
|
||||
if (!ret) {
|
||||
/* Match gain value from dt to one of supported gains */
|
||||
gain_idx = find_closest(st->gain_milli, ad4000_gains,
|
||||
ARRAY_SIZE(ad4000_gains));
|
||||
st->gain_milli = ad4000_gains[gain_idx];
|
||||
} else {
|
||||
return dev_err_probe(dev, ret,
|
||||
"Failed to read gain property\n");
|
||||
}
|
||||
}
|
||||
|
||||
ad4000_fill_scale_tbl(st, indio_dev->channels);
|
||||
|
||||
ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
|
||||
&iio_pollfunc_store_time,
|
||||
&ad4000_trigger_handler, NULL);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
return devm_iio_device_register(dev, indio_dev);
|
||||
}
|
||||
|
||||
static const struct spi_device_id ad4000_id[] = {
|
||||
{ "ad4000", (kernel_ulong_t)&ad4000_chip_info },
|
||||
{ "ad4001", (kernel_ulong_t)&ad4001_chip_info },
|
||||
{ "ad4002", (kernel_ulong_t)&ad4002_chip_info },
|
||||
{ "ad4003", (kernel_ulong_t)&ad4003_chip_info },
|
||||
{ "ad4004", (kernel_ulong_t)&ad4004_chip_info },
|
||||
{ "ad4005", (kernel_ulong_t)&ad4005_chip_info },
|
||||
{ "ad4006", (kernel_ulong_t)&ad4006_chip_info },
|
||||
{ "ad4007", (kernel_ulong_t)&ad4007_chip_info },
|
||||
{ "ad4008", (kernel_ulong_t)&ad4008_chip_info },
|
||||
{ "ad4010", (kernel_ulong_t)&ad4010_chip_info },
|
||||
{ "ad4011", (kernel_ulong_t)&ad4011_chip_info },
|
||||
{ "ad4020", (kernel_ulong_t)&ad4020_chip_info },
|
||||
{ "ad4021", (kernel_ulong_t)&ad4021_chip_info },
|
||||
{ "ad4022", (kernel_ulong_t)&ad4022_chip_info },
|
||||
{ "adaq4001", (kernel_ulong_t)&adaq4001_chip_info },
|
||||
{ "adaq4003", (kernel_ulong_t)&adaq4003_chip_info },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(spi, ad4000_id);
|
||||
|
||||
static const struct of_device_id ad4000_of_match[] = {
|
||||
{ .compatible = "adi,ad4000", .data = &ad4000_chip_info },
|
||||
{ .compatible = "adi,ad4001", .data = &ad4001_chip_info },
|
||||
{ .compatible = "adi,ad4002", .data = &ad4002_chip_info },
|
||||
{ .compatible = "adi,ad4003", .data = &ad4003_chip_info },
|
||||
{ .compatible = "adi,ad4004", .data = &ad4004_chip_info },
|
||||
{ .compatible = "adi,ad4005", .data = &ad4005_chip_info },
|
||||
{ .compatible = "adi,ad4006", .data = &ad4006_chip_info },
|
||||
{ .compatible = "adi,ad4007", .data = &ad4007_chip_info },
|
||||
{ .compatible = "adi,ad4008", .data = &ad4008_chip_info },
|
||||
{ .compatible = "adi,ad4010", .data = &ad4010_chip_info },
|
||||
{ .compatible = "adi,ad4011", .data = &ad4011_chip_info },
|
||||
{ .compatible = "adi,ad4020", .data = &ad4020_chip_info },
|
||||
{ .compatible = "adi,ad4021", .data = &ad4021_chip_info },
|
||||
{ .compatible = "adi,ad4022", .data = &ad4022_chip_info },
|
||||
{ .compatible = "adi,adaq4001", .data = &adaq4001_chip_info },
|
||||
{ .compatible = "adi,adaq4003", .data = &adaq4003_chip_info },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, ad4000_of_match);
|
||||
|
||||
static struct spi_driver ad4000_driver = {
|
||||
.driver = {
|
||||
.name = "ad4000",
|
||||
.of_match_table = ad4000_of_match,
|
||||
},
|
||||
.probe = ad4000_probe,
|
||||
.id_table = ad4000_id,
|
||||
};
|
||||
module_spi_driver(ad4000_driver);
|
||||
|
||||
MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@analog.com>");
|
||||
MODULE_DESCRIPTION("Analog Devices AD4000 ADC driver");
|
||||
MODULE_LICENSE("GPL");
|
Loading…
Reference in New Issue
Block a user