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-rw-r--r--MAINTAINERS7
-rw-r--r--drivers/iio/adc/Kconfig13
-rw-r--r--drivers/iio/adc/Makefile1
-rw-r--r--drivers/iio/adc/ad7768-1.c459
4 files changed, 480 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index d039f66a5cef..3ba38114853c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -862,6 +862,13 @@ S: Supported
F: drivers/iio/adc/ad7606.c
F: Documentation/devicetree/bindings/iio/adc/ad7606.txt
+ANALOG DEVICES INC AD7768-1 DRIVER
+M: Stefan Popa <stefan.popa@analog.com>
+L: linux-iio@vger.kernel.org
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: drivers/iio/adc/ad7768-1.c
+
ANALOG DEVICES INC AD9389B DRIVER
M: Hans Verkuil <hans.verkuil@cisco.com>
L: linux-media@vger.kernel.org
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index f9354e5ee65c..46ed6fa7e3f3 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -108,6 +108,19 @@ config AD7766
To compile this driver as a module, choose M here: the module will be
called ad7766.
+config AD7768_1
+ tristate "Analog Devices AD7768-1 ADC driver"
+ depends on SPI
+ select IIO_BUFFER
+ select IIO_TRIGGER
+ select IIO_TRIGGERED_BUFFER
+ help
+ Say yes here to build support for Analog Devices AD7768-1 SPI
+ simultaneously sampling sigma-delta analog to digital converter (ADC).
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad7768-1.
+
config AD7791
tristate "Analog Devices AD7791 ADC driver"
depends on SPI
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index b5d40d000474..79d6511f0af3 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o
obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o
obj-$(CONFIG_AD7606) += ad7606.o
obj-$(CONFIG_AD7766) += ad7766.o
+obj-$(CONFIG_AD7768_1) += ad7768-1.o
obj-$(CONFIG_AD7791) += ad7791.o
obj-$(CONFIG_AD7793) += ad7793.o
obj-$(CONFIG_AD7887) += ad7887.o
diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c
new file mode 100644
index 000000000000..78449e90b2f5
--- /dev/null
+++ b/drivers/iio/adc/ad7768-1.c
@@ -0,0 +1,459 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices AD7768-1 SPI ADC driver
+ *
+ * Copyright 2017 Analog Devices Inc.
+ */
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+/* AD7768 registers definition */
+#define AD7768_REG_CHIP_TYPE 0x3
+#define AD7768_REG_PROD_ID_L 0x4
+#define AD7768_REG_PROD_ID_H 0x5
+#define AD7768_REG_CHIP_GRADE 0x6
+#define AD7768_REG_SCRATCH_PAD 0x0A
+#define AD7768_REG_VENDOR_L 0x0C
+#define AD7768_REG_VENDOR_H 0x0D
+#define AD7768_REG_INTERFACE_FORMAT 0x14
+#define AD7768_REG_POWER_CLOCK 0x15
+#define AD7768_REG_ANALOG 0x16
+#define AD7768_REG_ANALOG2 0x17
+#define AD7768_REG_CONVERSION 0x18
+#define AD7768_REG_DIGITAL_FILTER 0x19
+#define AD7768_REG_SINC3_DEC_RATE_MSB 0x1A
+#define AD7768_REG_SINC3_DEC_RATE_LSB 0x1B
+#define AD7768_REG_DUTY_CYCLE_RATIO 0x1C
+#define AD7768_REG_SYNC_RESET 0x1D
+#define AD7768_REG_GPIO_CONTROL 0x1E
+#define AD7768_REG_GPIO_WRITE 0x1F
+#define AD7768_REG_GPIO_READ 0x20
+#define AD7768_REG_OFFSET_HI 0x21
+#define AD7768_REG_OFFSET_MID 0x22
+#define AD7768_REG_OFFSET_LO 0x23
+#define AD7768_REG_GAIN_HI 0x24
+#define AD7768_REG_GAIN_MID 0x25
+#define AD7768_REG_GAIN_LO 0x26
+#define AD7768_REG_SPI_DIAG_ENABLE 0x28
+#define AD7768_REG_ADC_DIAG_ENABLE 0x29
+#define AD7768_REG_DIG_DIAG_ENABLE 0x2A
+#define AD7768_REG_ADC_DATA 0x2C
+#define AD7768_REG_MASTER_STATUS 0x2D
+#define AD7768_REG_SPI_DIAG_STATUS 0x2E
+#define AD7768_REG_ADC_DIAG_STATUS 0x2F
+#define AD7768_REG_DIG_DIAG_STATUS 0x30
+#define AD7768_REG_MCLK_COUNTER 0x31
+
+/* AD7768_REG_CONVERSION */
+#define AD7768_CONV_MODE_MSK GENMASK(2, 0)
+#define AD7768_CONV_MODE(x) FIELD_PREP(AD7768_CONV_MODE_MSK, x)
+
+#define AD7768_RD_FLAG_MSK(x) (BIT(6) | ((x) & 0x3F))
+#define AD7768_WR_FLAG_MSK(x) ((x) & 0x3F)
+
+enum ad7768_conv_mode {
+ AD7768_CONTINUOUS,
+ AD7768_ONE_SHOT,
+ AD7768_SINGLE,
+ AD7768_PERIODIC,
+ AD7768_STANDBY
+};
+
+enum ad7768_pwrmode {
+ AD7768_ECO_MODE = 0,
+ AD7768_MED_MODE = 2,
+ AD7768_FAST_MODE = 3
+};
+
+static const struct iio_chan_spec ad7768_channels[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .indexed = 1,
+ .channel = 0,
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 24,
+ .storagebits = 32,
+ .shift = 8,
+ .endianness = IIO_BE,
+ },
+ },
+};
+
+struct ad7768_state {
+ struct spi_device *spi;
+ struct regulator *vref;
+ struct mutex lock;
+ struct completion completion;
+ struct iio_trigger *trig;
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ union {
+ __be32 d32;
+ u8 d8[2];
+ } data ____cacheline_aligned;
+};
+
+static int ad7768_spi_reg_read(struct ad7768_state *st, unsigned int addr,
+ unsigned int len)
+{
+ unsigned int shift;
+ int ret;
+
+ shift = 32 - (8 * len);
+ st->data.d8[0] = AD7768_RD_FLAG_MSK(addr);
+
+ ret = spi_write_then_read(st->spi, st->data.d8, 1,
+ &st->data.d32, len);
+ if (ret < 0)
+ return ret;
+
+ return (be32_to_cpu(st->data.d32) >> shift);
+}
+
+static int ad7768_spi_reg_write(struct ad7768_state *st,
+ unsigned int addr,
+ unsigned int val)
+{
+ st->data.d8[0] = AD7768_WR_FLAG_MSK(addr);
+ st->data.d8[1] = val & 0xFF;
+
+ return spi_write(st->spi, st->data.d8, 2);
+}
+
+static int ad7768_set_mode(struct ad7768_state *st,
+ enum ad7768_conv_mode mode)
+{
+ int regval;
+
+ regval = ad7768_spi_reg_read(st, AD7768_REG_CONVERSION, 1);
+ if (regval < 0)
+ return regval;
+
+ regval &= ~AD7768_CONV_MODE_MSK;
+ regval |= AD7768_CONV_MODE(mode);
+
+ return ad7768_spi_reg_write(st, AD7768_REG_CONVERSION, regval);
+}
+
+static int ad7768_scan_direct(struct iio_dev *indio_dev)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+ int readval, ret;
+
+ reinit_completion(&st->completion);
+
+ ret = ad7768_set_mode(st, AD7768_ONE_SHOT);
+ if (ret < 0)
+ return ret;
+
+ ret = wait_for_completion_timeout(&st->completion,
+ msecs_to_jiffies(1000));
+ if (!ret)
+ return -ETIMEDOUT;
+
+ readval = ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3);
+ if (readval < 0)
+ return readval;
+ /*
+ * Any SPI configuration of the AD7768-1 can only be
+ * performed in continuous conversion mode.
+ */
+ ret = ad7768_set_mode(st, AD7768_CONTINUOUS);
+ if (ret < 0)
+ return ret;
+
+ return readval;
+}
+
+static int ad7768_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg,
+ unsigned int writeval,
+ unsigned int *readval)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&st->lock);
+ if (readval) {
+ ret = ad7768_spi_reg_read(st, reg, 1);
+ if (ret < 0)
+ goto err_unlock;
+ *readval = ret;
+ ret = 0;
+ } else {
+ ret = ad7768_spi_reg_write(st, reg, writeval);
+ }
+err_unlock:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int ad7768_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+ int scale_uv, ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = ad7768_scan_direct(indio_dev);
+ if (ret >= 0)
+ *val = ret;
+
+ iio_device_release_direct_mode(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ scale_uv = regulator_get_voltage(st->vref);
+ if (scale_uv < 0)
+ return scale_uv;
+
+ *val = (scale_uv * 2) / 1000;
+ *val2 = chan->scan_type.realbits;
+
+ return IIO_VAL_FRACTIONAL_LOG2;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info ad7768_info = {
+ .read_raw = &ad7768_read_raw,
+ .debugfs_reg_access = &ad7768_reg_access,
+};
+
+static int ad7768_setup(struct ad7768_state *st)
+{
+ int ret;
+
+ /*
+ * Two writes to the SPI_RESET[1:0] bits are required to initiate
+ * a software reset. The bits must first be set to 11, and then
+ * to 10. When the sequence is detected, the reset occurs.
+ * See the datasheet, page 70.
+ */
+ ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x3);
+ if (ret)
+ return ret;
+
+ ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x2);
+ if (ret)
+ return ret;
+
+ /* Set power mode to fast */
+ return ad7768_spi_reg_write(st, AD7768_REG_POWER_CLOCK,
+ AD7768_FAST_MODE);
+}
+
+static irqreturn_t ad7768_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad7768_state *st = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ ret = spi_read(st->spi, &st->data.d32, 3);
+ if (ret < 0)
+ goto err_unlock;
+
+ iio_push_to_buffers_with_timestamp(indio_dev, &st->data.d32,
+ iio_get_time_ns(indio_dev));
+
+ iio_trigger_notify_done(indio_dev->trig);
+err_unlock:
+ mutex_unlock(&st->lock);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ad7768_interrupt(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct ad7768_state *st = iio_priv(indio_dev);
+
+ if (iio_buffer_enabled(indio_dev))
+ iio_trigger_poll(st->trig);
+ else
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+};
+
+static int ad7768_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+
+ iio_triggered_buffer_postenable(indio_dev);
+ /*
+ * Write a 1 to the LSB of the INTERFACE_FORMAT register to enter
+ * continuous read mode. Subsequent data reads do not require an
+ * initial 8-bit write to query the ADC_DATA register.
+ */
+ return ad7768_spi_reg_write(st, AD7768_REG_INTERFACE_FORMAT, 0x01);
+}
+
+static int ad7768_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct ad7768_state *st = iio_priv(indio_dev);
+ int ret;
+
+ /*
+ * To exit continuous read mode, perform a single read of the ADC_DATA
+ * reg (0x2C), which allows further configuration of the device.
+ */
+ ret = ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3);
+ if (ret < 0)
+ return ret;
+
+ return iio_triggered_buffer_predisable(indio_dev);
+}
+
+static const struct iio_buffer_setup_ops ad7768_buffer_ops = {
+ .postenable = &ad7768_buffer_postenable,
+ .predisable = &ad7768_buffer_predisable,
+};
+
+static const struct iio_trigger_ops ad7768_trigger_ops = {
+ .validate_device = iio_trigger_validate_own_device,
+};
+
+static void ad7768_regulator_disable(void *data)
+{
+ struct ad7768_state *st = data;
+
+ regulator_disable(st->vref);
+}
+
+static int ad7768_probe(struct spi_device *spi)
+{
+ struct ad7768_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->spi = spi;
+
+ st->vref = devm_regulator_get(&spi->dev, "vref");
+ if (IS_ERR(st->vref))
+ return PTR_ERR(st->vref);
+
+ ret = regulator_enable(st->vref);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to enable specified vref supply\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&spi->dev, ad7768_regulator_disable, st);
+ if (ret)
+ return ret;
+
+ spi_set_drvdata(spi, indio_dev);
+ mutex_init(&st->lock);
+
+ indio_dev->channels = ad7768_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad7768_channels);
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->info = &ad7768_info;
+ indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
+
+ ret = ad7768_setup(st);
+ if (ret < 0) {
+ dev_err(&spi->dev, "AD7768 setup failed\n");
+ return ret;
+ }
+
+ st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
+ indio_dev->name, indio_dev->id);
+ if (!st->trig)
+ return -ENOMEM;
+
+ st->trig->ops = &ad7768_trigger_ops;
+ st->trig->dev.parent = &spi->dev;
+ iio_trigger_set_drvdata(st->trig, indio_dev);
+ ret = devm_iio_trigger_register(&spi->dev, st->trig);
+ if (ret)
+ return ret;
+
+ indio_dev->trig = iio_trigger_get(st->trig);
+
+ init_completion(&st->completion);
+
+ ret = devm_request_irq(&spi->dev, spi->irq,
+ &ad7768_interrupt,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ indio_dev->name, indio_dev);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+ &iio_pollfunc_store_time,
+ &ad7768_trigger_handler,
+ &ad7768_buffer_ops);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id ad7768_id_table[] = {
+ { "ad7768-1", 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad7768_id_table);
+
+static const struct of_device_id ad7768_of_match[] = {
+ { .compatible = "adi,ad7768-1" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ad7768_of_match);
+
+static struct spi_driver ad7768_driver = {
+ .driver = {
+ .name = "ad7768-1",
+ .of_match_table = ad7768_of_match,
+ },
+ .probe = ad7768_probe,
+ .id_table = ad7768_id_table,
+};
+module_spi_driver(ad7768_driver);
+
+MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD7768-1 ADC driver");
+MODULE_LICENSE("GPL v2");