[PATCH 6/7] iio: adc: Add support for AD7091R-8
From: marcelo.schmitt
Date: Tue Nov 21 2023 - 16:37:04 EST
From: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
Add support for Analog Devices AD7091R-2, AD7091R-4, and AD7091R-8
low power 12-Bit SAR ADCs.
Extend ad7091r-base driver so it can be used by AD7091R-8 drivers.
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
---
Device read/write might look odd due to the transfer protocol for these devices.
I'm glad to hear any suggestions on how to make it better.
MAINTAINERS | 1 +
drivers/iio/adc/Kconfig | 16 ++
drivers/iio/adc/Makefile | 4 +-
drivers/iio/adc/ad7091r-base.c | 25 ++-
drivers/iio/adc/ad7091r-base.h | 15 ++
drivers/iio/adc/ad7091r5.c | 2 +
drivers/iio/adc/ad7091r8.c | 272 +++++++++++++++++++++++++++++++++
7 files changed, 327 insertions(+), 8 deletions(-)
create mode 100644 drivers/iio/adc/ad7091r8.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 6e7c6c866396..54eff6f0c358 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1136,6 +1136,7 @@ F: Documentation/devicetree/bindings/iio/adc/adi,ad7091r8.yaml
F: drivers/iio/adc/drivers/iio/adc/ad7091r-base.c
F: drivers/iio/adc/drivers/iio/adc/ad7091r-base.h
F: drivers/iio/adc/drivers/iio/adc/ad7091r5.c
+F: drivers/iio/adc/drivers/iio/adc/ad7091r8.c
ANALOG DEVICES INC AD7192 DRIVER
M: Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 1e2b7a2c67c6..284d898790a2 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -36,13 +36,29 @@ config AD4130
To compile this driver as a module, choose M here: the module will be
called ad4130.
+config AD7091R
+ tristate
+
config AD7091R5
tristate "Analog Devices AD7091R5 ADC Driver"
depends on I2C
+ select AD7091R
select REGMAP_I2C
help
Say yes here to build support for Analog Devices AD7091R-5 ADC.
+config AD7091R8
+ tristate "Analog Devices AD7091R8 ADC Driver"
+ depends on SPI
+ select AD7091R
+ select REGMAP_SPI
+ help
+ Say yes here to build support for Analog Devices AD7091R-2, AD7091R-4,
+ and AD7091R-8 ADC.
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad7091r8.
+
config AD7124
tristate "Analog Devices AD7124 and similar sigma-delta ADCs driver"
depends on SPI_MASTER
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index c0803383a7cc..d2fda54a3259 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -7,7 +7,9 @@
obj-$(CONFIG_AB8500_GPADC) += ab8500-gpadc.o
obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
obj-$(CONFIG_AD4130) += ad4130.o
-obj-$(CONFIG_AD7091R5) += ad7091r5.o ad7091r-base.o
+obj-$(CONFIG_AD7091R) += ad7091r-base.o
+obj-$(CONFIG_AD7091R5) += ad7091r5.o
+obj-$(CONFIG_AD7091R8) += ad7091r8.o
obj-$(CONFIG_AD7124) += ad7124.o
obj-$(CONFIG_AD7192) += ad7192.o
obj-$(CONFIG_AD7266) += ad7266.o
diff --git a/drivers/iio/adc/ad7091r-base.c b/drivers/iio/adc/ad7091r-base.c
index 69cb5ccdbc49..f9b4f91d1c4f 100644
--- a/drivers/iio/adc/ad7091r-base.c
+++ b/drivers/iio/adc/ad7091r-base.c
@@ -6,6 +6,7 @@
*/
#include <linux/bitops.h>
+#include <linux/bitfield.h>
#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/interrupt.h>
@@ -16,7 +17,8 @@
#include "ad7091r-base.h"
/* AD7091R_REG_RESULT */
-#define AD7091R_REG_RESULT_CH_ID(x) (((x) >> 13) & 0x3)
+#define AD7091R5_REG_RESULT_CH_ID(x) (((x) >> 13) & 0x3)
+#define AD7091R8_REG_RESULT_CH_ID(x) (((x) >> 13) & 0x7)
#define AD7091R_REG_RESULT_CONV_RESULT(x) ((x) & 0xfff)
/* AD7091R_REG_CONF */
@@ -45,10 +47,14 @@ static int ad7091r_set_mode(struct ad7091r_state *st, enum ad7091r_mode mode)
return -EINVAL;
}
- ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
- AD7091R_REG_CONF_MODE_MASK, conf);
- if (ret)
- return ret;
+ /* AD7091R-2/4/8 don't set normal, command, autocycle modes in conf reg */
+ if (st->chip_info->type == AD7091R5) {
+ return 0;
+ ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
+ AD7091R_REG_CONF_MODE_MASK, conf);
+ if (ret)
+ return ret;
+ }
st->mode = mode;
@@ -88,8 +94,13 @@ static int ad7091r_read_one(struct iio_dev *iio_dev,
if (ret)
return ret;
- if (AD7091R_REG_RESULT_CH_ID(val) != channel)
- return -EIO;
+ if (st->chip_info->type == AD7091R5) {
+ if (AD7091R5_REG_RESULT_CH_ID(val) != channel)
+ return -EIO;
+ } else {
+ if (AD7091R8_REG_RESULT_CH_ID(val) != channel)
+ return -EIO;
+ }
*read_val = AD7091R_REG_RESULT_CONV_RESULT(val);
diff --git a/drivers/iio/adc/ad7091r-base.h b/drivers/iio/adc/ad7091r-base.h
index 405939f4eee0..99e5053d1f44 100644
--- a/drivers/iio/adc/ad7091r-base.h
+++ b/drivers/iio/adc/ad7091r-base.h
@@ -29,6 +29,8 @@
.scan_type.realbits = bits, \
}
+#include <linux/gpio/consumer.h>
+
struct device;
enum ad7091r_mode {
@@ -40,13 +42,26 @@ enum ad7091r_mode {
struct ad7091r_state {
struct device *dev;
struct regmap *map;
+ struct gpio_desc *convst_gpio;
+ struct gpio_desc *reset_gpio;
struct regulator *vref;
const struct ad7091r_chip_info *chip_info;
enum ad7091r_mode mode;
struct mutex lock; /*lock to prevent concurent reads */
+ __be16 tx_buf __aligned(IIO_DMA_MINALIGN);
+ __be16 rx_buf;
+};
+
+enum ad7091r_device_type {
+ AD7091R2,
+ AD7091R4,
+ AD7091R5,
+ AD7091R8,
};
struct ad7091r_chip_info {
+ const char *name;
+ enum ad7091r_device_type type;
unsigned int num_channels;
const struct iio_chan_spec *channels;
unsigned int vref_mV;
diff --git a/drivers/iio/adc/ad7091r5.c b/drivers/iio/adc/ad7091r5.c
index 1a27841d1bbc..5f587e0b55df 100644
--- a/drivers/iio/adc/ad7091r5.c
+++ b/drivers/iio/adc/ad7091r5.c
@@ -27,12 +27,14 @@ static const struct iio_chan_spec ad7091r5_channels_noirq[] = {
};
static const struct ad7091r_chip_info ad7091r5_chip_info_irq = {
+ .type = AD7091R5,
.channels = ad7091r5_channels_irq,
.num_channels = ARRAY_SIZE(ad7091r5_channels_irq),
.vref_mV = 2500,
};
static const struct ad7091r_chip_info ad7091r5_chip_info_noirq = {
+ .type = AD7091R5,
.channels = ad7091r5_channels_noirq,
.num_channels = ARRAY_SIZE(ad7091r5_channels_noirq),
.vref_mV = 2500,
diff --git a/drivers/iio/adc/ad7091r8.c b/drivers/iio/adc/ad7091r8.c
new file mode 100644
index 000000000000..806d858d4c0e
--- /dev/null
+++ b/drivers/iio/adc/ad7091r8.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices AD7091R8 12-bit SAR ADC driver
+ *
+ * Copyright 2023 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/gpio/consumer.h>
+#include <linux/spi/spi.h>
+
+#include "ad7091r-base.h"
+
+#define AD7091R8_REG_ADDR_MSK GENMASK(15, 11)
+#define AD7091R8_RD_WR_FLAG_MSK BIT(10)
+#define AD7091R8_REG_DATA_MSK GENMASK(9, 0)
+
+#define AD7091R2_DEV_NAME "ad7091r-2"
+#define AD7091R4_DEV_NAME "ad7091r-4"
+#define AD7091R8_DEV_NAME "ad7091r-8"
+
+#define AD7091R_SPI_CHIP_INFO(n) { \
+ .name = AD7091R##n##_DEV_NAME, \
+ .type = AD7091R##n, \
+ .channels = ad7091r##n##_channels, \
+ .num_channels = ARRAY_SIZE(ad7091r##n##_channels), \
+ .vref_mV = 2500, \
+}
+
+#define AD7091R_SPI_CHIP_INFO_IRQ(n) { \
+ .name = AD7091R##n##_DEV_NAME, \
+ .type = AD7091R##n, \
+ .channels = ad7091r##n##_channels_irq, \
+ .num_channels = ARRAY_SIZE(ad7091r##n##_channels_irq), \
+ .vref_mV = 2500, \
+}
+
+static const struct iio_chan_spec ad7091r2_channels[] = {
+ AD7091R_CHANNEL(0, 12, NULL, 0),
+ AD7091R_CHANNEL(1, 12, NULL, 0),
+};
+
+static const struct iio_chan_spec ad7091r4_channels[] = {
+ AD7091R_CHANNEL(0, 12, NULL, 0),
+ AD7091R_CHANNEL(1, 12, NULL, 0),
+ AD7091R_CHANNEL(2, 12, NULL, 0),
+ AD7091R_CHANNEL(3, 12, NULL, 0),
+};
+
+static const struct iio_chan_spec ad7091r4_channels_irq[] = {
+ AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+};
+
+static const struct iio_chan_spec ad7091r8_channels[] = {
+ AD7091R_CHANNEL(0, 12, NULL, 0),
+ AD7091R_CHANNEL(1, 12, NULL, 0),
+ AD7091R_CHANNEL(2, 12, NULL, 0),
+ AD7091R_CHANNEL(3, 12, NULL, 0),
+ AD7091R_CHANNEL(4, 12, NULL, 0),
+ AD7091R_CHANNEL(5, 12, NULL, 0),
+ AD7091R_CHANNEL(6, 12, NULL, 0),
+ AD7091R_CHANNEL(7, 12, NULL, 0),
+};
+
+static const struct iio_chan_spec ad7091r8_channels_irq[] = {
+ AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(4, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(5, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(6, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+ AD7091R_CHANNEL(7, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
+};
+
+static const struct ad7091r_chip_info ad7091r_spi_chip_info[] = {
+ [AD7091R2] = AD7091R_SPI_CHIP_INFO(2),
+ [AD7091R4] = AD7091R_SPI_CHIP_INFO(4),
+ [AD7091R8] = AD7091R_SPI_CHIP_INFO(8),
+};
+
+static const struct ad7091r_chip_info ad7091r_spi_chip_info_irq[] = {
+ [AD7091R4] = AD7091R_SPI_CHIP_INFO_IRQ(4),
+ [AD7091R8] = AD7091R_SPI_CHIP_INFO_IRQ(8),
+};
+
+static void ad7091r_pulse_convst(struct ad7091r_state *st)
+{
+ gpiod_set_value_cansleep(st->convst_gpio, 1);
+ gpiod_set_value_cansleep(st->convst_gpio, 0);
+}
+
+static const struct regmap_config ad7091r_spi_regmap_config[] = {
+ [AD7091R2] = {
+ .reg_bits = 5,
+ .pad_bits = 3,
+ .val_bits = 16,
+ .volatile_reg = ad7091r_volatile_reg,
+ .writeable_reg = ad7091r_writeable_reg,
+ .max_register = AD7091R_REG_CH_HYSTERESIS(2),
+ },
+ [AD7091R4] = {
+ .reg_bits = 5,
+ .pad_bits = 3,
+ .val_bits = 16,
+ .volatile_reg = ad7091r_volatile_reg,
+ .writeable_reg = ad7091r_writeable_reg,
+ .max_register = AD7091R_REG_CH_HYSTERESIS(4),
+ },
+ [AD7091R8] = {
+ .reg_bits = 5,
+ .pad_bits = 3,
+ .write_flag_mask = BIT(2),
+ .val_bits = 16,
+ .volatile_reg = ad7091r_volatile_reg,
+ .writeable_reg = ad7091r_writeable_reg,
+ .max_register = AD7091R_REG_CH_HYSTERESIS(8),
+ },
+};
+
+static int ad7091r_regmap_bus_reg_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ struct ad7091r_state *st = context;
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+ const struct regmap_config *conf = &ad7091r_spi_regmap_config[st->chip_info->type];
+ int ret;
+
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->tx_buf,
+ .len = 2,
+ .cs_change = 1,
+ }, {
+ .rx_buf = &st->rx_buf,
+ .len = 2,
+ }
+ };
+
+ if (reg == AD7091R_REG_RESULT)
+ ad7091r_pulse_convst(st);
+
+ reg <<= conf->pad_bits;
+ st->tx_buf = cpu_to_be16(reg << 8);
+
+ ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
+ if (ret < 0)
+ return ret;
+
+ *val = be16_to_cpu(st->rx_buf);
+ return 0;
+}
+
+static int ad7091r_regmap_bus_reg_write(void *context, unsigned int reg,
+ unsigned int val)
+{
+ struct ad7091r_state *st = context;
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+
+ /*
+ * AD7091R-2/-4/-8 protocol (datasheet page 31) is to do a single SPI
+ * transfer with reg address set in bits B15:B11 and value set in B9:B0.
+ */
+ st->tx_buf = cpu_to_be16(FIELD_PREP(AD7091R8_REG_DATA_MSK, val) |
+ FIELD_PREP(AD7091R8_RD_WR_FLAG_MSK, 1) |
+ FIELD_PREP(AD7091R8_REG_ADDR_MSK, reg));
+
+ return spi_write(spi, &st->tx_buf, 2);
+}
+
+static struct regmap_bus ad7091r8_regmap_bus = {
+ .reg_read = ad7091r_regmap_bus_reg_read,
+ .reg_write = ad7091r_regmap_bus_reg_write,
+ .reg_format_endian_default = REGMAP_ENDIAN_BIG,
+ .val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
+static int ad7091r8_gpio_setup(struct ad7091r_state *st)
+{
+ st->convst_gpio = devm_gpiod_get(st->dev, "adi,conversion-start",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(st->convst_gpio))
+ return dev_err_probe(st->dev, PTR_ERR(st->convst_gpio),
+ "Error getting convst GPIO: %ld\n",
+ PTR_ERR(st->convst_gpio));
+
+ st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(st->reset_gpio))
+ return PTR_ERR(st->reset_gpio);
+
+ if (st->reset_gpio) {
+ fsleep(20);
+ gpiod_set_value_cansleep(st->reset_gpio, 0);
+ }
+
+ return 0;
+}
+
+static int ad7091r8_spi_probe(struct spi_device *spi)
+{
+ const struct ad7091r_chip_info *chip_info;
+ struct ad7091r_state *st;
+ struct iio_dev *iio_dev;
+ struct regmap *map;
+ int ret;
+
+ chip_info = spi_get_device_match_data(spi);
+ if (!chip_info)
+ return -EINVAL;
+
+ iio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!iio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(iio_dev);
+ st->dev = &spi->dev;
+
+ map = devm_regmap_init(&spi->dev, &ad7091r8_regmap_bus, st,
+ &ad7091r_spi_regmap_config[chip_info->type]);
+
+ if (IS_ERR(map))
+ return dev_err_probe(&spi->dev, PTR_ERR(map),
+ "Error initializing spi regmap: %ld\n",
+ PTR_ERR(map));
+
+ ret = ad7091r8_gpio_setup(st);
+ if (ret < 0)
+ return ret;
+
+ if (spi->irq)
+ chip_info = &ad7091r_spi_chip_info_irq[chip_info->type];
+
+ return ad7091r_probe(iio_dev, chip_info->name, chip_info, map, spi->irq);
+}
+
+static const struct of_device_id ad7091r8_of_match[] = {
+ { .compatible = "adi,ad7091r2", .data = &ad7091r_spi_chip_info[AD7091R2] },
+ { .compatible = "adi,ad7091r4", .data = &ad7091r_spi_chip_info[AD7091R4] },
+ { .compatible = "adi,ad7091r8", .data = &ad7091r_spi_chip_info[AD7091R8] },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ad7091r8_of_match);
+
+static const struct spi_device_id ad7091r8_spi_id[] = {
+ { "ad7091r2", (kernel_ulong_t)&ad7091r_spi_chip_info[AD7091R2] },
+ { "ad7091r4", (kernel_ulong_t)&ad7091r_spi_chip_info[AD7091R4] },
+ { "ad7091r8", (kernel_ulong_t)&ad7091r_spi_chip_info[AD7091R8] },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, ad7091r8_spi_id);
+
+static struct spi_driver ad7091r8_driver = {
+ .driver = {
+ .name = "ad7091r8",
+ .of_match_table = ad7091r8_of_match,
+ },
+ .probe = ad7091r8_spi_probe,
+ .id_table = ad7091r8_spi_id,
+};
+module_spi_driver(ad7091r8_driver);
+
+MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices AD7091R8 ADC driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_AD7091R);
--
2.42.0