2022-06-28 07:18:49

by Cosmin Tanislav

[permalink] [raw]
Subject: [PATCH v6 2/2] iio: adc: ad4130: add AD4130 driver

AD4130-8 is an ultra-low power, high precision, measurement solution for
low bandwidth battery operated applications.

The fully integrated AFE (Analog Front-End) includes a multiplexer for up
to 16 single-ended or 8 differential inputs, PGA (Programmable Gain
Amplifier), 24-bit Sigma-Delta ADC, on-chip reference and oscillator,
selectable filter options, smart sequencer, sensor biasing and excitation
options, diagnostics, and a FIFO buffer.

Signed-off-by: Cosmin Tanislav <[email protected]>
---
.../ABI/testing/sysfs-bus-iio-adc-ad4130 | 36 +
MAINTAINERS | 8 +
drivers/iio/adc/Kconfig | 13 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad4130.c | 2014 +++++++++++++++++
5 files changed, 2072 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
create mode 100644 drivers/iio/adc/ad4130.c

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130 b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
new file mode 100644
index 000000000000..90aa50cecfd1
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
@@ -0,0 +1,36 @@
+What: /sys/bus/iio/devices/iio:deviceX/in_voltage-voltage_filter_mode_available
+KernelVersion: 5.19
+Contact: [email protected]
+Description:
+ Reading returns a list with the possible filter modes.
+ "sinc4" - Sinc 4. Excellent noise performance. Long 1st
+ conversion time. No natural 50/60Hz rejection.
+ "sinc4+sinc1" - Sinc4 + averaging by 8. Low 1st conversion time.
+ "sinc3" - Sinc3. Moderate 1st conversion time. Good noise
+ performance.
+ "sinc3+rej60" - Sinc3 + 60Hz rejection. At a sampling frequency
+ of 50Hz, achieves simultaneous 50Hz and 60Hz
+ rejection.
+ "sinc3+sinc1" - Sinc3 + averaging by 8. Low 1st conversion time.
+ Best used with a sampling frequency of at least
+ 216.19Hz.
+ "sinc3+pf1" - Sinc3 + Post Filter 1.
+ 53dB rejection @ 50Hz, 58dB rejection @ 60Hz.
+ "sinc3+pf2" - Sinc3 + Post Filter 2.
+ 70dB rejection @ 50Hz, 70dB rejection @ 60Hz.
+ "sinc3+pf3" - Sinc3 + Post Filter 3.
+ 99dB rejection @ 50Hz, 103dB rejection @ 60Hz.
+ "sinc3+pf4" - Sinc3 + Post Filter 4.
+ 103dB rejection @ 50Hz, 109dB rejection @ 60Hz.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_voltageY-voltageZ_filter_mode
+KernelVersion: 5.19
+Contact: [email protected]
+Description:
+ Set the filter mode of the differential channel. When the filter
+ mode changes, the in_voltageY-voltageZ_sampling_frequency and
+ in_voltageY-voltageZ_sampling_frequency_available attributes
+ might also change to accommodate the new filter mode.
+ If the current sampling frequency is out of range for the new
+ filter mode, the sampling frequency will be changed to the
+ closest valid one.
diff --git a/MAINTAINERS b/MAINTAINERS
index a6d3bd9d2a8d..2981968260be 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1074,6 +1074,14 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git
T: git git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
F: drivers/net/amt.c

+ANALOG DEVICES INC AD4130 DRIVER
+M: Cosmin Tanislav <[email protected]>
+L: [email protected]
+S: Supported
+W: http://ez.analog.com/community/linux-device-drivers
+F: Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
+F: drivers/iio/adc/ad4130.c
+
ANALOG DEVICES INC AD7192 DRIVER
M: Alexandru Tachici <[email protected]>
L: [email protected]
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 7fe5930891e0..52387925e41f 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -21,6 +21,19 @@ config AD_SIGMA_DELTA
select IIO_BUFFER
select IIO_TRIGGERED_BUFFER

+config AD4130
+ tristate "Analog Device AD4130 ADC Driver"
+ depends on SPI
+ select IIO_BUFFER
+ select IIO_KFIFO_BUF
+ select REGMAP_SPI
+ help
+ Say yes here to build support for Analog Devices AD4130-8 SPI analog
+ to digital converters (ADC).
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad4130.
+
config AD7091R5
tristate "Analog Devices AD7091R5 ADC Driver"
depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 1772a549a3c8..9d8619753b39 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -6,6 +6,7 @@
# When adding new entries keep the list in alphabetical order
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-$(CONFIG_AD7124) += ad7124.o
obj-$(CONFIG_AD7192) += ad7192.o
diff --git a/drivers/iio/adc/ad4130.c b/drivers/iio/adc/ad4130.c
new file mode 100644
index 000000000000..b907f8b8eec8
--- /dev/null
+++ b/drivers/iio/adc/ad4130.c
@@ -0,0 +1,2014 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2022 Analog Devices, Inc.
+ * Author: Cosmin Tanislav <[email protected]>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/units.h>
+
+#include <asm/div64.h>
+#include <asm/unaligned.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/sysfs.h>
+
+#define AD4130_NAME "ad4130"
+
+#define AD4130_COMMS_READ_MASK BIT(6)
+
+#define AD4130_STATUS_REG 0x00
+#define AD4130_STATUS_POR_FLAG_MASK BIT(4)
+
+#define AD4130_ADC_CONTROL_REG 0x01
+#define AD4130_ADC_CONTROL_BIPOLAR_MASK BIT(14)
+#define AD4130_ADC_CONTROL_INT_REF_VAL_MASK BIT(13)
+#define AD4130_INT_REF_2_5V 2500000
+#define AD4130_INT_REF_1_25V 1250000
+#define AD4130_ADC_CONTROL_CSB_EN_MASK BIT(9)
+#define AD4130_ADC_CONTROL_INT_REF_EN_MASK BIT(8)
+#define AD4130_ADC_CONTROL_MODE_MASK GENMASK(5, 2)
+#define AD4130_ADC_CONTROL_MCLK_SEL_MASK GENMASK(1, 0)
+#define AD4130_MCLK_FREQ_76_8KHZ 76800
+#define AD4130_MCLK_FREQ_153_6KHZ 153600
+
+#define AD4130_DATA_REG 0x02
+
+#define AD4130_IO_CONTROL_REG 0x03
+#define AD4130_IO_CONTROL_INT_PIN_SEL_MASK GENMASK(9, 8)
+#define AD4130_IO_CONTROL_GPIO_DATA_MASK GENMASK(7, 4)
+#define AD4130_IO_CONTROL_GPIO_CTRL_MASK GENMASK(3, 0)
+
+#define AD4130_VBIAS_REG 0x04
+
+#define AD4130_ID_REG 0x05
+
+#define AD4130_ERROR_REG 0x06
+
+#define AD4130_ERROR_EN_REG 0x07
+
+#define AD4130_MCLK_COUNT_REG 0x08
+
+#define AD4130_CHANNEL_X_REG(x) (0x09 + (x))
+#define AD4130_CHANNEL_EN_MASK BIT(23)
+#define AD4130_CHANNEL_SETUP_MASK GENMASK(22, 20)
+#define AD4130_CHANNEL_AINP_MASK GENMASK(17, 13)
+#define AD4130_CHANNEL_AINM_MASK GENMASK(12, 8)
+#define AD4130_CHANNEL_IOUT1_MASK GENMASK(7, 4)
+#define AD4130_CHANNEL_IOUT2_MASK GENMASK(3, 0)
+
+#define AD4130_CONFIG_X_REG(x) (0x19 + (x))
+#define AD4130_CONFIG_IOUT1_VAL_MASK GENMASK(15, 13)
+#define AD4130_CONFIG_IOUT2_VAL_MASK GENMASK(12, 10)
+#define AD4130_CONFIG_BURNOUT_MASK GENMASK(9, 8)
+#define AD4130_CONFIG_REF_BUFP_MASK BIT(7)
+#define AD4130_CONFIG_REF_BUFM_MASK BIT(6)
+#define AD4130_CONFIG_REF_SEL_MASK GENMASK(5, 4)
+#define AD4130_CONFIG_PGA_MASK GENMASK(3, 1)
+
+#define AD4130_FILTER_X_REG(x) (0x21 + (x))
+#define AD4130_FILTER_MODE_MASK GENMASK(15, 12)
+#define AD4130_FILTER_SELECT_MASK GENMASK(10, 0)
+#define AD4130_FILTER_SELECT_MIN 1
+
+#define AD4130_OFFSET_X_REG(x) (0x29 + (x))
+
+#define AD4130_GAIN_X_REG(x) (0x31 + (x))
+
+#define AD4130_MISC_REG 0x39
+
+#define AD4130_FIFO_CONTROL_REG 0x3a
+#define AD4130_FIFO_CONTROL_HEADER_MASK BIT(18)
+#define AD4130_FIFO_CONTROL_MODE_MASK GENMASK(17, 16)
+#define AD4130_FIFO_CONTROL_WM_INT_EN_MASK BIT(9)
+#define AD4130_FIFO_CONTROL_WM_MASK GENMASK(7, 0)
+#define AD4130_WATERMARK_256 0
+
+#define AD4130_FIFO_STATUS_REG 0x3b
+
+#define AD4130_FIFO_THRESHOLD_REG 0x3c
+
+#define AD4130_FIFO_DATA_REG 0x3d
+#define AD4130_FIFO_SIZE 256
+#define AD4130_FIFO_MAX_SAMPLE_SIZE 3
+
+#define AD4130_MAX_ANALOG_PINS 16
+#define AD4130_MAX_CHANNELS 16
+#define AD4130_MAX_DIFF_INPUTS 30
+#define AD4130_MAX_GPIOS 4
+#define AD4130_MAX_ODR 2400
+#define AD4130_MAX_PGA 8
+#define AD4130_MAX_SETUPS 8
+
+#define AD4130_AIN2_P1 0x2
+#define AD4130_AIN3_P2 0x3
+
+#define AD4130_RESET_BUF_SIZE 8
+#define AD4130_RESET_SLEEP_US (160 * MICRO / AD4130_MCLK_FREQ_76_8KHZ)
+
+#define AD4130_INVALID_SLOT -1
+
+static const unsigned int ad4130_reg_size[] = {
+ [AD4130_STATUS_REG] = 1,
+ [AD4130_ADC_CONTROL_REG] = 2,
+ [AD4130_DATA_REG] = 3,
+ [AD4130_IO_CONTROL_REG] = 2,
+ [AD4130_VBIAS_REG] = 2,
+ [AD4130_ID_REG] = 1,
+ [AD4130_ERROR_REG] = 2,
+ [AD4130_ERROR_EN_REG] = 2,
+ [AD4130_MCLK_COUNT_REG] = 1,
+ [AD4130_CHANNEL_X_REG(0) ... AD4130_CHANNEL_X_REG(AD4130_MAX_CHANNELS)] = 3,
+ [AD4130_CONFIG_X_REG(0) ... AD4130_CONFIG_X_REG(AD4130_MAX_SETUPS)] = 2,
+ [AD4130_FILTER_X_REG(0) ... AD4130_FILTER_X_REG(AD4130_MAX_SETUPS)] = 3,
+ [AD4130_OFFSET_X_REG(0) ... AD4130_OFFSET_X_REG(AD4130_MAX_SETUPS)] = 3,
+ [AD4130_GAIN_X_REG(0) ... AD4130_GAIN_X_REG(AD4130_MAX_SETUPS)] = 3,
+ [AD4130_MISC_REG] = 2,
+ [AD4130_FIFO_CONTROL_REG] = 3,
+ [AD4130_FIFO_STATUS_REG] = 1,
+ [AD4130_FIFO_THRESHOLD_REG] = 3,
+ [AD4130_FIFO_DATA_REG] = 3,
+};
+
+enum ad4130_id {
+ ID_AD4130_8_24_WLCSP,
+ ID_AD4130_8_24_LFCSP,
+ ID_AD4130_8_16_WLCSP,
+ ID_AD4130_8_16_LFCSP,
+};
+
+enum ad4130_int_ref_val {
+ AD4130_INT_REF_VAL_2_5V,
+ AD4130_INT_REF_VAL_1_25V,
+};
+
+enum ad4130_mclk_sel {
+ AD4130_MCLK_76_8KHZ,
+ AD4130_MCLK_76_8KHZ_OUT,
+ AD4130_MCLK_76_8KHZ_EXT,
+ AD4130_MCLK_153_6KHZ_EXT,
+ AD4130_MCLK_SEL_MAX
+};
+
+enum ad4130_int_pin_sel {
+ AD4130_INT_PIN_INT,
+ AD4130_INT_PIN_CLK,
+ AD4130_INT_PIN_P2,
+ AD4130_INT_PIN_DOUT,
+};
+
+enum ad4130_iout {
+ AD4130_IOUT_OFF,
+ AD4130_IOUT_10000NA,
+ AD4130_IOUT_20000NA,
+ AD4130_IOUT_50000NA,
+ AD4130_IOUT_100000NA,
+ AD4130_IOUT_150000NA,
+ AD4130_IOUT_200000NA,
+ AD4130_IOUT_100NA,
+ AD4130_IOUT_MAX
+};
+
+enum ad4130_burnout {
+ AD4130_BURNOUT_OFF,
+ AD4130_BURNOUT_500NA,
+ AD4130_BURNOUT_2000NA,
+ AD4130_BURNOUT_4000NA,
+ AD4130_BURNOUT_MAX
+};
+
+enum ad4130_ref_sel {
+ AD4130_REF_REFIN1,
+ AD4130_REF_REFIN2,
+ AD4130_REF_REFOUT_AVSS,
+ AD4130_REF_AVDD_AVSS,
+ AD4130_REF_SEL_MAX
+};
+
+enum ad4130_fifo_mode {
+ AD4130_FIFO_MODE_DISABLED = 0b00,
+ AD4130_FIFO_MODE_WM = 0b01,
+};
+
+enum ad4130_mode {
+ AD4130_MODE_CONTINUOUS = 0b0000,
+ AD4130_MODE_IDLE = 0b0100,
+};
+
+enum ad4130_filter_mode {
+ AD4130_FILTER_SINC4,
+ AD4130_FILTER_SINC4_SINC1,
+ AD4130_FILTER_SINC3,
+ AD4130_FILTER_SINC3_REJ60,
+ AD4130_FILTER_SINC3_SINC1,
+ AD4130_FILTER_SINC3_PF1,
+ AD4130_FILTER_SINC3_PF2,
+ AD4130_FILTER_SINC3_PF3,
+ AD4130_FILTER_SINC3_PF4,
+};
+
+enum ad4130_pin_function {
+ AD4130_PIN_FN_NONE,
+ AD4130_PIN_FN_SPECIAL = BIT(0),
+ AD4130_PIN_FN_DIFF = BIT(1),
+ AD4130_PIN_FN_EXCITATION = BIT(2),
+ AD4130_PIN_FN_VBIAS = BIT(3),
+};
+
+struct ad4130_setup_info {
+ unsigned int iout0_val;
+ unsigned int iout1_val;
+ unsigned int burnout;
+ unsigned int pga;
+ unsigned int fs;
+ u32 ref_sel;
+ enum ad4130_filter_mode filter_mode;
+ bool ref_bufp;
+ bool ref_bufm;
+};
+
+struct ad4130_slot_info {
+ struct ad4130_setup_info setup;
+ unsigned int enabled_channels;
+ unsigned int channels;
+};
+
+struct ad4130_chan_info {
+ struct ad4130_setup_info setup;
+ u32 iout0;
+ u32 iout1;
+ int slot;
+ bool enabled;
+ bool initialized;
+};
+
+struct ad4130_filter_config {
+ enum ad4130_filter_mode filter_mode;
+ unsigned int odr_div;
+ unsigned int fs_max;
+ enum iio_available_type samp_freq_avail_type;
+ int samp_freq_avail_len;
+ int samp_freq_avail[3][2];
+};
+
+struct ad4130_state {
+ struct regmap *regmap;
+ struct spi_device *spi;
+ struct clk *mclk;
+ struct regulator_bulk_data regulators[4];
+ u32 irq_trigger;
+ u32 inv_irq_trigger;
+
+ /*
+ * Synchronize access to members the of driver state, and ensure
+ * atomicity of consecutive regmap operations.
+ */
+ struct mutex lock;
+ struct completion completion;
+
+ struct iio_chan_spec chans[AD4130_MAX_CHANNELS];
+ struct ad4130_chan_info chans_info[AD4130_MAX_CHANNELS];
+ struct ad4130_slot_info slots_info[AD4130_MAX_SETUPS];
+ enum ad4130_pin_function pins_fn[AD4130_MAX_ANALOG_PINS];
+ u32 vbias_pins[AD4130_MAX_ANALOG_PINS];
+ u32 num_vbias_pins;
+ int scale_tbls[AD4130_REF_SEL_MAX][AD4130_MAX_PGA][2];
+ struct gpio_chip gc;
+
+ u32 int_pin_sel;
+ u32 int_ref_uv;
+ u32 mclk_sel;
+ bool int_ref_en;
+ bool bipolar;
+
+ unsigned int num_enabled_channels;
+ unsigned int effective_watermark;
+ unsigned int watermark;
+
+ struct spi_message fifo_msg;
+ struct spi_transfer fifo_xfer[2];
+
+ /*
+ * DMA (thus cache coherency maintenance) requires any transfer
+ * buffers to live in their own cache lines. As the use of these
+ * buffers is synchronous, all of the buffers used for DMA in this
+ * driver may share a cache line.
+ */
+ u8 reset_buf[AD4130_RESET_BUF_SIZE] __aligned(IIO_DMA_MINALIGN);
+ u8 reg_write_tx_buf[4];
+ u8 reg_read_tx_buf[1];
+ u8 reg_read_rx_buf[3];
+ u8 fifo_tx_buf[2];
+ u8 fifo_rx_buf[AD4130_FIFO_SIZE *
+ AD4130_FIFO_MAX_SAMPLE_SIZE];
+};
+
+static const char * const ad4130_int_pin_names[] = {
+ [AD4130_INT_PIN_INT] = "int",
+ [AD4130_INT_PIN_CLK] = "clk",
+ [AD4130_INT_PIN_P2] = "p2",
+ [AD4130_INT_PIN_DOUT] = "dout",
+};
+
+static const unsigned int ad4130_iout_current_na_tbl[AD4130_IOUT_MAX] = {
+ [AD4130_IOUT_OFF] = 0,
+ [AD4130_IOUT_100NA] = 100,
+ [AD4130_IOUT_10000NA] = 10000,
+ [AD4130_IOUT_20000NA] = 20000,
+ [AD4130_IOUT_50000NA] = 50000,
+ [AD4130_IOUT_100000NA] = 100000,
+ [AD4130_IOUT_150000NA] = 150000,
+ [AD4130_IOUT_200000NA] = 200000,
+};
+
+static const unsigned int ad4130_burnout_current_na_tbl[AD4130_BURNOUT_MAX] = {
+ [AD4130_BURNOUT_OFF] = 0,
+ [AD4130_BURNOUT_500NA] = 500,
+ [AD4130_BURNOUT_2000NA] = 2000,
+ [AD4130_BURNOUT_4000NA] = 4000,
+};
+
+#define AD4130_VARIABLE_ODR_CONFIG(_filter_mode, _odr_div, _fs_max) \
+{ \
+ .filter_mode = (_filter_mode), \
+ .odr_div = (_odr_div), \
+ .fs_max = (_fs_max), \
+ .samp_freq_avail_type = IIO_AVAIL_RANGE, \
+ .samp_freq_avail = { \
+ { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \
+ { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \
+ { AD4130_MAX_ODR, (_odr_div) }, \
+ }, \
+}
+
+#define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div) \
+{ \
+ .filter_mode = (_filter_mode), \
+ .odr_div = (_odr_div), \
+ .fs_max = AD4130_FILTER_SELECT_MIN, \
+ .samp_freq_avail_type = IIO_AVAIL_LIST, \
+ .samp_freq_avail_len = 1, \
+ .samp_freq_avail = { \
+ { AD4130_MAX_ODR, (_odr_div) }, \
+ }, \
+}
+
+static const struct ad4130_filter_config ad4130_filter_configs[] = {
+ AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4, 1, 10),
+ AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10),
+ AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3, 1, 2047),
+ AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1, 2047),
+ AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047),
+ AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1, 92),
+ AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2, 100),
+ AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3, 124),
+ AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4, 148),
+};
+
+static const char * const ad4130_filter_modes_str[] = {
+ [AD4130_FILTER_SINC4] = "sinc4",
+ [AD4130_FILTER_SINC4_SINC1] = "sinc4+sinc1",
+ [AD4130_FILTER_SINC3] = "sinc3",
+ [AD4130_FILTER_SINC3_REJ60] = "sinc3+rej60",
+ [AD4130_FILTER_SINC3_SINC1] = "sinc3+sinc1",
+ [AD4130_FILTER_SINC3_PF1] = "sinc3+pf1",
+ [AD4130_FILTER_SINC3_PF2] = "sinc3+pf2",
+ [AD4130_FILTER_SINC3_PF3] = "sinc3+pf3",
+ [AD4130_FILTER_SINC3_PF4] = "sinc3+pf4",
+};
+
+static int ad4130_get_reg_size(struct ad4130_state *st, unsigned int reg,
+ unsigned int *size)
+{
+ if (reg >= ARRAY_SIZE(ad4130_reg_size))
+ return -EINVAL;
+
+ *size = ad4130_reg_size[reg];
+
+ return 0;
+}
+
+static unsigned int ad4130_data_reg_size(struct ad4130_state *st)
+{
+ unsigned int data_reg_size;
+ int ret;
+
+ ret = ad4130_get_reg_size(st, AD4130_DATA_REG, &data_reg_size);
+ if (ret)
+ return 0;
+
+ return data_reg_size;
+}
+
+static unsigned int ad4130_resolution(struct ad4130_state *st)
+{
+ return ad4130_data_reg_size(st) * BITS_PER_BYTE;
+}
+
+static int ad4130_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct ad4130_state *st = context;
+ unsigned int size;
+ int ret;
+
+ ret = ad4130_get_reg_size(st, reg, &size);
+ if (ret)
+ return ret;
+
+ st->reg_write_tx_buf[0] = reg;
+
+ switch (size) {
+ case 3:
+ put_unaligned_be24(val, &st->reg_write_tx_buf[1]);
+ break;
+ case 2:
+ put_unaligned_be16(val, &st->reg_write_tx_buf[1]);
+ break;
+ case 1:
+ st->reg_write_tx_buf[1] = val;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return spi_write(st->spi, st->reg_write_tx_buf, size + 1);
+}
+
+static int ad4130_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct ad4130_state *st = context;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = st->reg_read_tx_buf,
+ .len = sizeof(st->reg_read_tx_buf),
+ },
+ {
+ .rx_buf = st->reg_read_rx_buf,
+ },
+ };
+ unsigned int size;
+ int ret;
+
+ ret = ad4130_get_reg_size(st, reg, &size);
+ if (ret)
+ return ret;
+
+ st->reg_read_tx_buf[0] = AD4130_COMMS_READ_MASK | reg;
+ t[1].len = size;
+
+ ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+ if (ret)
+ return ret;
+
+ switch (size) {
+ case 3:
+ *val = get_unaligned_be24(st->reg_read_rx_buf);
+ break;
+ case 2:
+ *val = get_unaligned_be16(st->reg_read_rx_buf);
+ break;
+ case 1:
+ *val = st->reg_read_rx_buf[0];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct regmap_config ad4130_regmap_config = {
+ .reg_read = ad4130_reg_read,
+ .reg_write = ad4130_reg_write,
+};
+
+static int ad4130_gpio_init_valid_mask(struct gpio_chip *gc,
+ unsigned long *valid_mask,
+ unsigned int ngpios)
+{
+ struct ad4130_state *st = gpiochip_get_data(gc);
+ unsigned int i;
+
+ /*
+ * Output-only GPIO functionality is available on pins AIN2 through
+ * AIN5. If these pins are used for anything else, do not expose them.
+ */
+ for (i = 0; i < ngpios; i++) {
+ unsigned int pin = i + AD4130_AIN2_P1;
+ bool valid = st->pins_fn[pin] == AD4130_PIN_FN_NONE;
+
+ __assign_bit(i, valid_mask, valid);
+ }
+
+
+ return 0;
+}
+
+static int ad4130_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ return GPIO_LINE_DIRECTION_OUT;
+}
+
+static void ad4130_gpio_set(struct gpio_chip *gc, unsigned int offset,
+ int value)
+{
+ struct ad4130_state *st = gpiochip_get_data(gc);
+ unsigned int mask = FIELD_PREP(AD4130_IO_CONTROL_GPIO_DATA_MASK,
+ BIT(offset));
+
+ regmap_update_bits(st->regmap, AD4130_IO_CONTROL_REG, mask,
+ value ? mask : 0);
+}
+
+static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode)
+{
+ return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
+ AD4130_ADC_CONTROL_MODE_MASK,
+ FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, mode));
+}
+
+static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en)
+{
+ return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
+ AD4130_FIFO_CONTROL_WM_INT_EN_MASK,
+ FIELD_PREP(AD4130_FIFO_CONTROL_WM_INT_EN_MASK, en));
+}
+
+static unsigned int ad4130_watermark_reg_val(unsigned int val)
+{
+ if (val == AD4130_FIFO_SIZE)
+ val = AD4130_WATERMARK_256;
+
+ return val;
+}
+
+static int ad4130_set_fifo_mode(struct ad4130_state *st,
+ enum ad4130_fifo_mode mode)
+{
+ return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
+ AD4130_FIFO_CONTROL_MODE_MASK,
+ FIELD_PREP(AD4130_FIFO_CONTROL_MODE_MASK, mode));
+}
+
+static void ad4130_push_fifo_data(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int data_reg_size = ad4130_data_reg_size(st);
+ unsigned int transfer_len = st->effective_watermark * data_reg_size;
+ unsigned int set_size = st->num_enabled_channels * data_reg_size;
+ unsigned int i;
+ int ret;
+
+ st->fifo_tx_buf[1] = ad4130_watermark_reg_val(st->effective_watermark);
+ st->fifo_xfer[1].len = transfer_len;
+
+ ret = spi_sync(st->spi, &st->fifo_msg);
+ if (ret)
+ return;
+
+ for (i = 0; i < transfer_len; i += set_size)
+ iio_push_to_buffers(indio_dev, &st->fifo_rx_buf[i]);
+}
+
+static irqreturn_t ad4130_irq_handler(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct ad4130_state *st = iio_priv(indio_dev);
+
+ if (iio_buffer_enabled(indio_dev))
+ ad4130_push_fifo_data(indio_dev);
+ else
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+}
+
+static int ad4130_find_slot(struct ad4130_state *st,
+ struct ad4130_setup_info *target_setup_info,
+ unsigned int *slot, bool *overwrite)
+{
+ unsigned int i;
+
+ *slot = AD4130_INVALID_SLOT;
+ *overwrite = false;
+
+ for (i = 0; i < AD4130_MAX_SETUPS; i++) {
+ struct ad4130_slot_info *slot_info = &st->slots_info[i];
+
+ /* Immediately accept a matching setup info. */
+ if (!memcmp(target_setup_info, &slot_info->setup,
+ sizeof(*target_setup_info))) {
+ *slot = i;
+ return 0;
+ }
+
+ /* Ignore all setups which are used by enabled channels. */
+ if (slot_info->enabled_channels)
+ continue;
+
+ /* Find the least used slot. */
+ if (*slot == AD4130_INVALID_SLOT ||
+ slot_info->channels < st->slots_info[*slot].channels)
+ *slot = i;
+ }
+
+ if (*slot == AD4130_INVALID_SLOT)
+ return -EINVAL;
+
+ *overwrite = true;
+
+ return 0;
+}
+
+static void ad4130_unlink_channel(struct ad4130_state *st, unsigned int channel)
+{
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_slot_info *slot_info = &st->slots_info[chan_info->slot];
+
+ chan_info->slot = AD4130_INVALID_SLOT;
+ slot_info->channels--;
+}
+
+static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot)
+{
+ unsigned int i;
+
+ for (i = 0; i < AD4130_MAX_CHANNELS; i++) {
+ struct ad4130_chan_info *chan_info = &st->chans_info[i];
+
+ if (!chan_info->initialized || chan_info->slot != slot)
+ continue;
+
+ ad4130_unlink_channel(st, i);
+ }
+
+ return 0;
+}
+
+static int ad4130_link_channel_slot(struct ad4130_state *st,
+ unsigned int channel, unsigned int slot)
+{
+ struct ad4130_slot_info *slot_info = &st->slots_info[slot];
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ int ret;
+
+ ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
+ AD4130_CHANNEL_SETUP_MASK,
+ FIELD_PREP(AD4130_CHANNEL_SETUP_MASK, slot));
+ if (ret)
+ return ret;
+
+ chan_info->slot = slot;
+ slot_info->channels++;
+
+ return 0;
+}
+
+static int ad4130_write_slot_setup(struct ad4130_state *st,
+ unsigned int slot,
+ struct ad4130_setup_info *setup_info)
+{
+ unsigned int val;
+ int ret;
+
+ val = FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout0_val) |
+ FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout1_val) |
+ FIELD_PREP(AD4130_CONFIG_BURNOUT_MASK, setup_info->burnout) |
+ FIELD_PREP(AD4130_CONFIG_REF_BUFP_MASK, setup_info->ref_bufp) |
+ FIELD_PREP(AD4130_CONFIG_REF_BUFM_MASK, setup_info->ref_bufm) |
+ FIELD_PREP(AD4130_CONFIG_REF_SEL_MASK, setup_info->ref_sel) |
+ FIELD_PREP(AD4130_CONFIG_PGA_MASK, setup_info->pga);
+
+ ret = regmap_write(st->regmap, AD4130_CONFIG_X_REG(slot), val);
+ if (ret)
+ return ret;
+
+ val = FIELD_PREP(AD4130_FILTER_MODE_MASK, setup_info->filter_mode) |
+ FIELD_PREP(AD4130_FILTER_SELECT_MASK, setup_info->fs);
+
+ ret = regmap_write(st->regmap, AD4130_FILTER_X_REG(slot), val);
+ if (ret)
+ return ret;
+
+ memcpy(&st->slots_info[slot].setup, setup_info, sizeof(*setup_info));
+
+ return 0;
+}
+
+static int ad4130_write_channel_setup(struct ad4130_state *st,
+ unsigned int channel, bool on_enable)
+{
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_setup_info *setup_info = &chan_info->setup;
+ bool overwrite;
+ int slot;
+ int ret;
+
+ /*
+ * The following cases need to be handled.
+ *
+ * 1. Enabled and linked channel with setup changes:
+ * - Find a slot. If not possible, return error.
+ * - Unlink channel from current slot.
+ * - If the slot has channels linked to it, unlink all channels, and
+ * write the new setup to it.
+ * - Link channel to new slot.
+ *
+ * 2. Soon to be enabled and unlinked channel:
+ * - Find a slot. If not possible, return error.
+ * - If the slot has channels linked to it, unlink all channels, and
+ * write the new setup to it.
+ * - Link channel to the slot.
+ *
+ * 3. Disabled and linked channel with setup changes:
+ * - Unlink channel from current slot.
+ *
+ * 4. Soon to be enabled and linked channel:
+ * 5. Disabled and unlinked channel with setup changes:
+ * - Do nothing.
+ */
+
+ /* Case 4 */
+ if (on_enable && chan_info->slot != AD4130_INVALID_SLOT)
+ return 0;
+
+ if (!on_enable && !chan_info->enabled) {
+ if (chan_info->slot != AD4130_INVALID_SLOT)
+ /* Case 3 */
+ ad4130_unlink_channel(st, channel);
+
+ /* Cases 3 & 5 */
+ return 0;
+ }
+
+ /* Cases 1 & 2 */
+ ret = ad4130_find_slot(st, setup_info, &slot, &overwrite);
+ if (ret)
+ return ret;
+
+ if (chan_info->slot != AD4130_INVALID_SLOT)
+ /* Case 1 */
+ ad4130_unlink_channel(st, channel);
+
+ if (overwrite) {
+ ret = ad4130_unlink_slot(st, slot);
+ if (ret)
+ return ret;
+
+ ret = ad4130_write_slot_setup(st, slot, setup_info);
+ if (ret)
+ return ret;
+ }
+
+ return ad4130_link_channel_slot(st, channel, slot);
+}
+
+static int ad4130_set_channel_enable(struct ad4130_state *st,
+ unsigned int channel, bool status)
+{
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_slot_info *slot_info;
+ int ret;
+
+ if (chan_info->enabled == status)
+ return 0;
+
+ if (status) {
+ ret = ad4130_write_channel_setup(st, channel, true);
+ if (ret)
+ return ret;
+ }
+
+ slot_info = &st->slots_info[chan_info->slot];
+
+ ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
+ AD4130_CHANNEL_EN_MASK,
+ FIELD_PREP(AD4130_CHANNEL_EN_MASK, status));
+ if (ret)
+ return ret;
+
+ slot_info->enabled_channels += status ? 1 : -1;
+ chan_info->enabled = status;
+
+ return 0;
+}
+
+/*
+ * Table 58. FILTER_MODE_n bits and Filter Types of the datasheet describes
+ * the relation between filter mode, ODR and FS.
+ *
+ * Notice that the max ODR of each filter mode is not necessarily the
+ * absolute max ODR supported by the chip.
+ *
+ * The ODR divider is not explicitly specified, but it can be deduced based
+ * on the ODR range of each filter mode.
+ *
+ * For example, for Sinc4+Sinc1, max ODR is 218.18. That means that the
+ * absolute max ODR is divided by 11 to achieve the max ODR of this filter
+ * mode.
+ *
+ * The formulas for converting between ODR and FS for a specific filter
+ * mode can be deduced from the same table.
+ *
+ * Notice that FS = 1 actually means max ODR, and that ODR decreases by
+ * (maximum ODR / maximum FS) for each increment of FS.
+ *
+ * odr = MAX_ODR / odr_div * (1 - (fs - 1) / fs_max) <=>
+ * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
+ * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
+ * odr = MAX_ODR * (fs_max - fs + 1) / (fs_max * odr_div)
+ * (used in ad4130_fs_to_freq)
+ *
+ * For the opposite formula, FS can be extracted from the last one.
+ *
+ * MAX_ODR * (fs_max - fs + 1) = fs_max * odr_div * odr <=>
+ * fs_max - fs + 1 = fs_max * odr_div * odr / MAX_ODR <=>
+ * fs = 1 + fs_max - fs_max * odr_div * odr / MAX_ODR
+ * (used in ad4130_fs_to_freq)
+ */
+
+static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode,
+ int val, int val2, unsigned int *fs)
+{
+ const struct ad4130_filter_config *filter_config =
+ &ad4130_filter_configs[filter_mode];
+ u64 dividend, divisor;
+ int temp;
+
+ dividend = filter_config->fs_max * filter_config->odr_div *
+ ((u64)val * NANO + val2);
+ divisor = (u64)AD4130_MAX_ODR * NANO;
+
+ temp = AD4130_FILTER_SELECT_MIN + filter_config->fs_max -
+ DIV64_U64_ROUND_CLOSEST(dividend, divisor);
+
+ if (temp < AD4130_FILTER_SELECT_MIN)
+ temp = AD4130_FILTER_SELECT_MIN;
+ else if (temp > filter_config->fs_max)
+ temp = filter_config->fs_max;
+
+ *fs = temp;
+}
+
+static void ad4130_fs_to_freq(enum ad4130_filter_mode filter_mode,
+ unsigned int fs, int *val, int *val2)
+{
+ const struct ad4130_filter_config *filter_config =
+ &ad4130_filter_configs[filter_mode];
+ unsigned int dividend, divisor;
+ u64 temp;
+
+ dividend = (filter_config->fs_max - fs + AD4130_FILTER_SELECT_MIN) *
+ AD4130_MAX_ODR;
+ divisor = filter_config->fs_max * filter_config->odr_div;
+
+ temp = div_u64((u64)dividend * NANO, divisor);
+ *val = div_u64_rem(temp, NANO, val2);
+}
+
+static int ad4130_set_filter_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int val)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel = chan->scan_index;
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_setup_info *setup_info = &chan_info->setup;
+ enum ad4130_filter_mode old_filter_mode;
+ int freq_val, freq_val2;
+ unsigned int old_fs;
+ int ret = 0;
+
+ mutex_lock(&st->lock);
+ if (setup_info->filter_mode == val)
+ goto out;
+
+ old_fs = setup_info->fs;
+ old_filter_mode = setup_info->filter_mode;
+
+ /*
+ * When switching between filter modes, try to match the ODR as
+ * close as possible. To do this, convert the current FS into ODR
+ * using the old filter mode, then convert it back into FS using
+ * the new filter mode.
+ */
+ ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
+ &freq_val, &freq_val2);
+
+ ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs);
+
+ setup_info->filter_mode = val;
+
+ ret = ad4130_write_channel_setup(st, channel, false);
+ if (ret) {
+ setup_info->fs = old_fs;
+ setup_info->filter_mode = old_filter_mode;
+ }
+
+ out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int ad4130_get_filter_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel = chan->scan_index;
+ struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
+ enum ad4130_filter_mode filter_mode;
+
+ mutex_lock(&st->lock);
+ filter_mode = setup_info->filter_mode;
+ mutex_unlock(&st->lock);
+
+ return filter_mode;
+}
+
+static const struct iio_enum ad4130_filter_mode_enum = {
+ .items = ad4130_filter_modes_str,
+ .num_items = ARRAY_SIZE(ad4130_filter_modes_str),
+ .set = ad4130_set_filter_mode,
+ .get = ad4130_get_filter_mode,
+};
+
+static const struct iio_chan_spec_ext_info ad4130_filter_mode_ext_info[] = {
+ IIO_ENUM("filter_mode", IIO_SEPARATE, &ad4130_filter_mode_enum),
+ IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_TYPE,
+ &ad4130_filter_mode_enum),
+ { }
+};
+
+static const struct iio_chan_spec ad4130_channel_template = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .differential = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .ext_info = ad4130_filter_mode_ext_info,
+ .scan_type = {
+ .sign = 'u',
+ .endianness = IIO_BE,
+ },
+};
+
+static int ad4130_set_channel_pga(struct ad4130_state *st, unsigned int channel,
+ int val, int val2)
+{
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_setup_info *setup_info = &chan_info->setup;
+ unsigned int pga, old_pga;
+ int ret = 0;
+
+ for (pga = 0; pga < AD4130_MAX_PGA; pga++)
+ if (val == st->scale_tbls[setup_info->ref_sel][pga][0] &&
+ val2 == st->scale_tbls[setup_info->ref_sel][pga][1])
+ break;
+
+ if (pga == AD4130_MAX_PGA)
+ return -EINVAL;
+
+ mutex_lock(&st->lock);
+ if (pga == setup_info->pga)
+ goto out;
+
+ old_pga = setup_info->pga;
+ setup_info->pga = pga;
+
+ ret = ad4130_write_channel_setup(st, channel, false);
+ if (ret)
+ setup_info->pga = old_pga;
+
+out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int ad4130_set_channel_freq(struct ad4130_state *st,
+ unsigned int channel, int val, int val2)
+{
+ struct ad4130_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4130_setup_info *setup_info = &chan_info->setup;
+ unsigned int fs, old_fs;
+ int ret = 0;
+
+ mutex_lock(&st->lock);
+ old_fs = setup_info->fs;
+
+ ad4130_freq_to_fs(setup_info->filter_mode, val, val2, &fs);
+
+ if (fs == setup_info->fs)
+ goto out;
+
+ setup_info->fs = fs;
+
+ ret = ad4130_write_channel_setup(st, channel, false);
+ if (ret)
+ setup_info->fs = old_fs;
+
+out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int _ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
+ int *val)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = ad4130_set_channel_enable(st, channel, true);
+ if (ret)
+ return ret;
+
+ reinit_completion(&st->completion);
+
+ ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
+ if (ret)
+ return ret;
+
+ ret = wait_for_completion_timeout(&st->completion,
+ msecs_to_jiffies(1000));
+ if (!ret)
+ return -ETIMEDOUT;
+
+ ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(st->regmap, AD4130_DATA_REG, val);
+ if (ret)
+ return ret;
+
+ ret = ad4130_set_channel_enable(st, channel, false);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+}
+
+static int ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
+ int *val)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ mutex_lock(&st->lock);
+ ret = _ad4130_read_sample(indio_dev, channel, val);
+ mutex_unlock(&st->lock);
+
+ iio_device_release_direct_mode(indio_dev);
+
+ return ret;
+}
+
+static int ad4130_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel = chan->scan_index;
+ struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ return ad4130_read_sample(indio_dev, channel, val);
+ case IIO_CHAN_INFO_SCALE:
+ mutex_lock(&st->lock);
+ *val = st->scale_tbls[setup_info->ref_sel][setup_info->pga][0];
+ *val2 = st->scale_tbls[setup_info->ref_sel][setup_info->pga][1];
+ mutex_unlock(&st->lock);
+
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_CHAN_INFO_OFFSET:
+ *val = st->bipolar ? -BIT(chan->scan_type.realbits - 1) : 0;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ mutex_lock(&st->lock);
+ ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
+ val, val2);
+ mutex_unlock(&st->lock);
+
+ return IIO_VAL_INT_PLUS_NANO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4130_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long info)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel = chan->scan_index;
+ struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
+ const struct ad4130_filter_config *filter_config;
+
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ *vals = (int *)st->scale_tbls[setup_info->ref_sel];
+ *length = ARRAY_SIZE(st->scale_tbls[setup_info->ref_sel]) * 2;
+
+ *type = IIO_VAL_INT_PLUS_NANO;
+
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ mutex_lock(&st->lock);
+ filter_config = &ad4130_filter_configs[setup_info->filter_mode];
+ mutex_unlock(&st->lock);
+
+ *vals = (int *)filter_config->samp_freq_avail;
+ *length = filter_config->samp_freq_avail_len * 2;
+ *type = IIO_VAL_FRACTIONAL;
+
+ return filter_config->samp_freq_avail_type;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4130_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ long info)
+{
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return IIO_VAL_INT_PLUS_NANO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4130_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long info)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel = chan->scan_index;
+
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ return ad4130_set_channel_pga(st, channel, val, val2);
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return ad4130_set_channel_freq(st, channel, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4130_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+ unsigned int writeval, unsigned int *readval)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+
+ if (readval)
+ return regmap_read(st->regmap, reg, readval);
+
+ return regmap_write(st->regmap, reg, writeval);
+}
+
+static int ad4130_update_scan_mode(struct iio_dev *indio_dev,
+ const unsigned long *scan_mask)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int channel;
+ unsigned int val = 0;
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ for_each_set_bit(channel, scan_mask, indio_dev->num_channels) {
+ ret = ad4130_set_channel_enable(st, channel, true);
+ if (ret)
+ goto out;
+
+ val++;
+ }
+
+ st->num_enabled_channels = val;
+
+out:
+ mutex_unlock(&st->lock);
+
+ return 0;
+}
+
+static int ad4130_set_fifo_watermark(struct iio_dev *indio_dev, unsigned int val)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int eff;
+ int ret;
+
+ if (val > AD4130_FIFO_SIZE)
+ return -EINVAL;
+
+ eff = val * st->num_enabled_channels;
+ if (eff > AD4130_FIFO_SIZE)
+ /*
+ * Always set watermark to a multiple of the number of
+ * enabled channels to avoid making the FIFO unaligned.
+ */
+ eff = rounddown(AD4130_FIFO_SIZE, st->num_enabled_channels);
+
+ mutex_lock(&st->lock);
+
+ ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
+ AD4130_FIFO_CONTROL_WM_MASK,
+ FIELD_PREP(AD4130_FIFO_CONTROL_WM_MASK,
+ ad4130_watermark_reg_val(eff)));
+ if (ret)
+ goto out;
+
+ st->effective_watermark = eff;
+ st->watermark = val;
+
+out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static const struct iio_info ad4130_info = {
+ .read_raw = ad4130_read_raw,
+ .read_avail = ad4130_read_avail,
+ .write_raw_get_fmt = ad4130_write_raw_get_fmt,
+ .write_raw = ad4130_write_raw,
+ .update_scan_mode = ad4130_update_scan_mode,
+ .hwfifo_set_watermark = ad4130_set_fifo_watermark,
+ .debugfs_reg_access = ad4130_reg_access,
+};
+
+static int ad4130_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ ret = ad4130_set_watermark_interrupt_en(st, true);
+ if (ret)
+ goto out;
+
+ ret = irq_set_irq_type(st->spi->irq, st->inv_irq_trigger);
+ if (ret)
+ goto out;
+
+ ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_WM);
+ if (ret)
+ goto out;
+
+ ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
+
+out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static int ad4130_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int i;
+ int ret;
+
+ mutex_lock(&st->lock);
+
+ ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
+ if (ret)
+ goto out;
+
+ ret = irq_set_irq_type(st->spi->irq, st->irq_trigger);
+ if (ret)
+ goto out;
+
+ ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_DISABLED);
+ if (ret)
+ goto out;
+
+ ret = ad4130_set_watermark_interrupt_en(st, false);
+ if (ret)
+ goto out;
+
+ /*
+ * update_scan_mode() is not called in the disable path, disable all
+ * channels here.
+ */
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ ret = ad4130_set_channel_enable(st, i, false);
+ if (ret)
+ goto out;
+ }
+
+out:
+ mutex_unlock(&st->lock);
+
+ return ret;
+}
+
+static const struct iio_buffer_setup_ops ad4130_buffer_ops = {
+ .postenable = ad4130_buffer_postenable,
+ .predisable = ad4130_buffer_predisable,
+};
+
+static ssize_t hwfifo_watermark_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
+ unsigned int val;
+
+ mutex_lock(&st->lock);
+ val = st->watermark;
+ mutex_unlock(&st->lock);
+
+ return sysfs_emit(buf, "%d\n", val);
+}
+
+static ssize_t hwfifo_enabled_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(st->regmap, AD4130_FIFO_CONTROL_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(AD4130_FIFO_CONTROL_MODE_MASK, val);
+
+ return sysfs_emit(buf, "%d\n", val != AD4130_FIFO_MODE_DISABLED);
+}
+
+static IIO_CONST_ATTR(hwfifo_watermark_min, "1");
+static IIO_CONST_ATTR(hwfifo_watermark_max, __stringify(AD4130_FIFO_SIZE));
+static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0);
+static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0);
+
+static const struct attribute *ad4130_fifo_attributes[] = {
+ &iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
+ &iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
+ &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
+ &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
+ NULL
+};
+
+static int _ad4130_find_table_index(const unsigned int *tbl, size_t len,
+ unsigned int val)
+{
+ unsigned int i;
+
+ for (i = 0; i < len; i++)
+ if (tbl[i] == val)
+ return i;
+
+ return -EINVAL;
+}
+
+#define ad4130_find_table_index(table, val) \
+ _ad4130_find_table_index(table, ARRAY_SIZE(table), val)
+
+static int ad4130_get_ref_voltage(struct ad4130_state *st,
+ enum ad4130_ref_sel ref_sel)
+{
+ switch (ref_sel) {
+ case AD4130_REF_REFIN1:
+ return regulator_get_voltage(st->regulators[2].consumer);
+ case AD4130_REF_REFIN2:
+ return regulator_get_voltage(st->regulators[3].consumer);
+ case AD4130_REF_AVDD_AVSS:
+ return regulator_get_voltage(st->regulators[0].consumer);
+ case AD4130_REF_REFOUT_AVSS:
+ return st->int_ref_uv;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4130_parse_fw_setup(struct ad4130_state *st,
+ struct fwnode_handle *child,
+ struct ad4130_setup_info *setup_info)
+{
+ struct device *dev = &st->spi->dev;
+ u32 tmp;
+ int ret;
+
+ tmp = 0;
+ fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamp", &tmp);
+ ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid excitation current %unA\n", tmp);
+ setup_info->iout0_val = ret;
+
+ tmp = 0;
+ fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamp", &tmp);
+ ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid excitation current %unA\n", tmp);
+ setup_info->iout1_val = ret;
+
+ tmp = 0;
+ fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp);
+ ret = ad4130_find_table_index(ad4130_burnout_current_na_tbl, tmp);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid burnout current %unA\n", tmp);
+ setup_info->burnout = ret;
+
+ setup_info->ref_bufp = fwnode_property_read_bool(child, "adi,buffered-positive");
+ setup_info->ref_bufm = fwnode_property_read_bool(child, "adi,buffered-negative");
+
+ setup_info->ref_sel = AD4130_REF_REFIN1;
+ fwnode_property_read_u32(child, "adi,reference-select",
+ &setup_info->ref_sel);
+ if (setup_info->ref_sel >= AD4130_REF_SEL_MAX)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid reference selected %u\n",
+ setup_info->ref_sel);
+
+ if (setup_info->ref_sel == AD4130_REF_REFOUT_AVSS)
+ st->int_ref_en = true;
+
+ ret = ad4130_get_ref_voltage(st, setup_info->ref_sel);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Cannot use reference %u\n",
+ setup_info->ref_sel);
+
+ return 0;
+}
+
+static int ad4130_validate_diff_channel(struct ad4130_state *st, u32 pin)
+{
+ struct device *dev = &st->spi->dev;
+
+ if (pin >= AD4130_MAX_DIFF_INPUTS)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid diffreential channel %u\n", pin);
+
+ if (pin >= AD4130_MAX_ANALOG_PINS)
+ return 0;
+
+ if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
+ return dev_err_probe(dev, -EINVAL,
+ "Pin %u already used with fn %u\n", pin,
+ st->pins_fn[pin]);
+
+ st->pins_fn[pin] |= AD4130_PIN_FN_DIFF;
+
+ return 0;
+}
+
+static int ad4130_validate_diff_channels(struct ad4130_state *st,
+ u32 *pins, unsigned int len)
+{
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < len; i++) {
+ ret = ad4130_validate_diff_channel(st, pins[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ad4130_validate_excitation_pin(struct ad4130_state *st, u32 pin)
+{
+ struct device *dev = &st->spi->dev;
+
+ if (pin >= AD4130_MAX_ANALOG_PINS)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid excitation pin %u\n", pin);
+
+ if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
+ return dev_err_probe(dev, -EINVAL,
+ "Pin %u already used with fn %u\n", pin,
+ st->pins_fn[pin]);
+
+ st->pins_fn[pin] |= AD4130_PIN_FN_EXCITATION;
+
+ return 0;
+}
+
+static int ad4130_validate_vbias_pin(struct ad4130_state *st, u32 pin)
+{
+ struct device *dev = &st->spi->dev;
+
+ if (pin >= AD4130_MAX_ANALOG_PINS)
+ return dev_err_probe(dev, -EINVAL, "Invalid vbias pin %u\n",
+ pin);
+
+ if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
+ return dev_err_probe(dev, -EINVAL,
+ "Pin %u already used with fn %u\n", pin,
+ st->pins_fn[pin]);
+
+ st->pins_fn[pin] |= AD4130_PIN_FN_VBIAS;
+
+ return 0;
+}
+
+static int ad4130_validate_vbias_pins(struct ad4130_state *st,
+ u32 *pins, unsigned int len)
+{
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < st->num_vbias_pins; i++) {
+ ret = ad4130_validate_vbias_pin(st, pins[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ad4130_parse_fw_channel(struct iio_dev *indio_dev,
+ struct fwnode_handle *child)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ unsigned int resolution = ad4130_resolution(st);
+ unsigned int index = indio_dev->num_channels++;
+ struct device *dev = &st->spi->dev;
+ struct ad4130_chan_info *chan_info;
+ struct iio_chan_spec *chan;
+ u32 pins[2];
+ int ret;
+
+ if (index >= AD4130_MAX_CHANNELS)
+ return dev_err_probe(dev, -EINVAL, "Too many channels\n");
+
+ chan = &st->chans[index];
+ chan_info = &st->chans_info[index];
+
+ *chan = ad4130_channel_template;
+ chan->scan_type.realbits = resolution;
+ chan->scan_type.storagebits = resolution;
+ chan->scan_index = index;
+
+ chan_info->slot = AD4130_INVALID_SLOT;
+ chan_info->setup.fs = AD4130_FILTER_SELECT_MIN;
+ chan_info->initialized = true;
+
+ ret = fwnode_property_read_u32_array(child, "diff-channels", pins,
+ ARRAY_SIZE(pins));
+ if (ret)
+ return ret;
+
+ ret = ad4130_validate_diff_channels(st, pins, ARRAY_SIZE(pins));
+ if (ret)
+ return ret;
+
+ chan->channel = pins[0];
+ chan->channel2 = pins[1];
+
+ ret = ad4130_parse_fw_setup(st, child, &chan_info->setup);
+ if (ret)
+ return ret;
+
+ fwnode_property_read_u32(child, "adi,excitation-pin-0",
+ &chan_info->iout0);
+ if (chan_info->setup.iout0_val != AD4130_IOUT_OFF) {
+ ret = ad4130_validate_excitation_pin(st, chan_info->iout0);
+ if (ret)
+ return ret;
+ }
+
+ fwnode_property_read_u32(child, "adi,excitation-pin-1",
+ &chan_info->iout1);
+ if (chan_info->setup.iout1_val != AD4130_IOUT_OFF) {
+ ret = ad4130_validate_excitation_pin(st, chan_info->iout1);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ad4130_parse_fw_children(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ struct fwnode_handle *child;
+ int ret;
+
+ indio_dev->channels = st->chans;
+
+ device_for_each_child_node(dev, child) {
+ ret = ad4130_parse_fw_channel(indio_dev, child);
+ if (ret) {
+ fwnode_handle_put(child);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int ad4310_parse_fw(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ u32 ext_clk_freq = AD4130_MCLK_FREQ_76_8KHZ;
+ bool int_clk_out;
+ unsigned int i;
+ int avdd_uv;
+ int irq;
+ int ret;
+
+ st->mclk = devm_clk_get_optional(dev, "mclk");
+ if (IS_ERR(st->mclk))
+ return dev_err_probe(dev, PTR_ERR(st->mclk),
+ "Failed to get mclk\n");
+
+ st->int_pin_sel = AD4130_INT_PIN_INT;
+
+ for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) {
+ irq = fwnode_irq_get_byname(dev_fwnode(dev),
+ ad4130_int_pin_names[i]);
+ if (irq > 0) {
+ st->int_pin_sel = i;
+ break;
+ }
+ }
+
+ if (st->int_pin_sel == AD4130_INT_PIN_DOUT)
+ return dev_err_probe(dev, -EINVAL,
+ "Cannot use DOUT as interrupt pin\n");
+
+ if (st->int_pin_sel == AD4130_INT_PIN_P2)
+ st->pins_fn[AD4130_AIN3_P2] = AD4130_PIN_FN_SPECIAL;
+
+ int_clk_out = device_property_read_bool(dev, "adi,int-clk-out");
+ if (st->mclk && int_clk_out)
+ return dev_err_probe(dev, -EINVAL,
+ "Cannot expose internal clock\n");
+
+ device_property_read_u32(dev, "adi,ext-clk-freq-hz", &ext_clk_freq);
+ if (ext_clk_freq != AD4130_MCLK_FREQ_153_6KHZ &&
+ ext_clk_freq != AD4130_MCLK_FREQ_76_8KHZ)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid external clock frequency %u\n",
+ ext_clk_freq);
+
+ if (st->mclk && ext_clk_freq == AD4130_MCLK_FREQ_153_6KHZ)
+ st->mclk_sel = AD4130_MCLK_153_6KHZ_EXT;
+ else if (st->mclk)
+ st->mclk_sel = AD4130_MCLK_76_8KHZ_EXT;
+ else if (int_clk_out)
+ st->mclk_sel = AD4130_MCLK_76_8KHZ_OUT;
+ else
+ st->mclk_sel = AD4130_MCLK_76_8KHZ;
+
+ if (st->int_pin_sel == AD4130_INT_PIN_CLK &&
+ st->mclk_sel != AD4130_MCLK_76_8KHZ)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid clock %u for interrupt pin %u\n",
+ st->mclk_sel, st->int_pin_sel);
+
+ st->int_ref_uv = AD4130_INT_REF_2_5V;
+
+ /*
+ * When the AVDD supply is set to below 2.5V the internal reference of
+ * 1.25V should be selected.
+ * See datasheet page 37, section ADC REFERENCE.
+ */
+ avdd_uv = regulator_get_voltage(st->regulators[0].consumer);
+ if (avdd_uv > 0 && avdd_uv < AD4130_INT_REF_2_5V)
+ st->int_ref_uv = AD4130_INT_REF_1_25V;
+
+ st->bipolar = device_property_read_bool(dev, "adi,bipolar");
+
+ ret = device_property_count_u32(dev, "adi,vbias-pins");
+ if (ret > 0) {
+ if (ret > AD4130_MAX_ANALOG_PINS)
+ return dev_err_probe(dev, -EINVAL,
+ "Too many vbias pins %u\n", ret);
+
+ st->num_vbias_pins = ret;
+
+ ret = device_property_read_u32_array(dev, "adi,vbias-pins",
+ st->vbias_pins,
+ st->num_vbias_pins);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to read vbias pins\n");
+
+ ret = ad4130_validate_vbias_pins(st, st->vbias_pins,
+ st->num_vbias_pins);
+ if (ret)
+ return ret;
+ }
+
+ ret = ad4130_parse_fw_children(indio_dev);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static void ad4130_fill_scale_tbls(struct ad4130_state *st)
+{
+ unsigned int pow = ad4130_resolution(st) - st->bipolar;
+ unsigned int i, j;
+
+ for (i = 0; i < AD4130_REF_SEL_MAX; i++) {
+ int ret;
+ u64 nv;
+
+ ret = ad4130_get_ref_voltage(st, i);
+ if (ret < 0)
+ continue;
+
+ nv = (u64)ret * NANO;
+
+ for (j = 0; j < AD4130_MAX_PGA; j++)
+ st->scale_tbls[i][j][1] = div_u64(nv >> (pow + j), MILLI);
+ }
+}
+
+static void ad4130_clk_disable_unprepare(void *clk)
+{
+ clk_disable_unprepare(clk);
+}
+
+static int ad4130_setup(struct iio_dev *indio_dev)
+{
+ struct ad4130_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ unsigned int int_ref_val;
+ unsigned long rate = AD4130_MCLK_FREQ_76_8KHZ;
+ unsigned int val;
+ unsigned int i;
+ int ret;
+
+ if (st->mclk_sel == AD4130_MCLK_153_6KHZ_EXT)
+ rate = AD4130_MCLK_FREQ_153_6KHZ;
+
+ ret = clk_set_rate(st->mclk, rate);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(st->mclk);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(dev, ad4130_clk_disable_unprepare,
+ st->mclk);
+ if (ret)
+ return ret;
+
+ if (st->int_ref_uv == AD4130_INT_REF_2_5V)
+ int_ref_val = AD4130_INT_REF_VAL_2_5V;
+ else
+ int_ref_val = AD4130_INT_REF_VAL_1_25V;
+
+ /* Switch to SPI 4-wire mode. */
+ val = FIELD_PREP(AD4130_ADC_CONTROL_CSB_EN_MASK, 1);
+ val |= FIELD_PREP(AD4130_ADC_CONTROL_BIPOLAR_MASK, st->bipolar);
+ val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_EN_MASK, st->int_ref_en);
+ val |= FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, AD4130_MODE_IDLE);
+ val |= FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, st->mclk_sel);
+ val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_VAL_MASK, int_ref_val);
+
+ ret = regmap_write(st->regmap, AD4130_ADC_CONTROL_REG, val);
+ if (ret)
+ return ret;
+
+ /*
+ * Configure all GPIOs for output. If configured, the interrupt function
+ * of P2 takes priority over the GPIO out function.
+ */
+ val = AD4130_IO_CONTROL_GPIO_CTRL_MASK;
+ val |= FIELD_PREP(AD4130_IO_CONTROL_INT_PIN_SEL_MASK, st->int_pin_sel);
+
+ ret = regmap_write(st->regmap, AD4130_IO_CONTROL_REG, val);
+ if (ret)
+ return ret;
+
+ val = 0;
+ for (i = 0; i < st->num_vbias_pins; i++)
+ val |= BIT(st->vbias_pins[i]);
+
+ ret = regmap_write(st->regmap, AD4130_VBIAS_REG, val);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
+ AD4130_FIFO_CONTROL_HEADER_MASK, 0);
+ if (ret)
+ return ret;
+
+ /* FIFO watermark interrupt starts out as enabled, disable it. */
+ ret = ad4130_set_watermark_interrupt_en(st, false);
+ if (ret)
+ return ret;
+
+ /* Setup channels. */
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ struct ad4130_chan_info *chan_info = &st->chans_info[i];
+ struct iio_chan_spec *chan = &st->chans[i];
+ unsigned int val;
+
+ val = FIELD_PREP(AD4130_CHANNEL_AINP_MASK, chan->channel) |
+ FIELD_PREP(AD4130_CHANNEL_AINM_MASK, chan->channel2) |
+ FIELD_PREP(AD4130_CHANNEL_IOUT1_MASK, chan_info->iout0) |
+ FIELD_PREP(AD4130_CHANNEL_IOUT2_MASK, chan_info->iout1);
+
+ ret = regmap_write(st->regmap, AD4130_CHANNEL_X_REG(i), val);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ad4130_soft_reset(struct ad4130_state *st)
+{
+ int ret;
+
+ ret = spi_write(st->spi, st->reset_buf, sizeof(st->reset_buf));
+ if (ret)
+ return ret;
+
+ fsleep(AD4130_RESET_SLEEP_US);
+
+ return 0;
+}
+
+static void ad4130_disable_regulators(void *data)
+{
+ struct ad4130_state *st = data;
+
+ regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators);
+}
+
+static int ad4130_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct iio_dev *indio_dev;
+ struct ad4130_state *st;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+
+ memset(st->reset_buf, 0xff, sizeof(st->reset_buf));
+ init_completion(&st->completion);
+ mutex_init(&st->lock);
+ st->spi = spi;
+
+ /*
+ * Xfer: [ XFR1 ] [ XFR2 ]
+ * Master: 0x7D N ......................
+ * Slave: ...... DATA1 DATA2 ... DATAN
+ */
+ st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_FIFO_DATA_REG;
+ st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
+ st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
+ st->fifo_xfer[1].rx_buf = st->fifo_rx_buf;
+ spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer,
+ ARRAY_SIZE(st->fifo_xfer));
+
+ indio_dev->name = AD4130_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &ad4130_info;
+
+ st->regmap = devm_regmap_init(dev, NULL, st, &ad4130_regmap_config);
+ if (IS_ERR(st->regmap))
+ return PTR_ERR(st->regmap);
+
+ st->regulators[0].supply = "avdd";
+ st->regulators[1].supply = "iovdd";
+ st->regulators[2].supply = "refin1";
+ st->regulators[3].supply = "refin2";
+
+ ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators),
+ st->regulators);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to get regulators\n");
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to enable regulators\n");
+
+ ret = devm_add_action_or_reset(dev, ad4130_disable_regulators, st);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to add regulators disable action\n");
+
+ ret = ad4130_soft_reset(st);
+ if (ret)
+ return ret;
+
+ ret = ad4310_parse_fw(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = ad4130_setup(indio_dev);
+ if (ret)
+ return ret;
+
+ ad4130_fill_scale_tbls(st);
+
+ st->gc.owner = THIS_MODULE;
+ st->gc.label = AD4130_NAME;
+ st->gc.base = -1;
+ st->gc.ngpio = AD4130_MAX_GPIOS;
+ st->gc.parent = dev;
+ st->gc.can_sleep = true;
+ st->gc.init_valid_mask = ad4130_gpio_init_valid_mask;
+ st->gc.get_direction = ad4130_gpio_get_direction;
+ st->gc.set = ad4130_gpio_set;
+
+ ret = devm_gpiochip_add_data(dev, &st->gc, st);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev,
+ &ad4130_buffer_ops,
+ ad4130_fifo_attributes);
+ if (ret)
+ return ret;
+
+ ret = devm_request_threaded_irq(dev, spi->irq, NULL,
+ ad4130_irq_handler, IRQF_ONESHOT,
+ indio_dev->name, indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to request irq\n");
+
+ /*
+ * When the chip enters FIFO mode, IRQ polarity is inverted.
+ * When the chip exits FIFO mode, IRQ polarity returns to normal.
+ * See datasheet pages: 65, FIFO Watermark Interrupt section,
+ * and 71, Bit Descriptions for STATUS Register, RDYB.
+ * Cache the normal and inverted IRQ triggers to set them when
+ * entering and exiting FIFO mode.
+ */
+ st->irq_trigger = irq_get_trigger_type(spi->irq);
+ if (st->irq_trigger & IRQF_TRIGGER_RISING)
+ st->inv_irq_trigger = IRQF_TRIGGER_FALLING;
+ else if (st->irq_trigger & IRQF_TRIGGER_FALLING)
+ st->inv_irq_trigger = IRQF_TRIGGER_RISING;
+ else
+ return dev_err_probe(dev, -EINVAL, "Invalid irq flags: %u\n",
+ st->irq_trigger);
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id ad4130_of_match[] = {
+ {
+ .compatible = "adi,ad4130",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad4130_of_match);
+
+static struct spi_driver ad4130_driver = {
+ .driver = {
+ .name = AD4130_NAME,
+ .of_match_table = ad4130_of_match,
+ },
+ .probe = ad4130_probe,
+};
+module_spi_driver(ad4130_driver);
+
+MODULE_AUTHOR("Cosmin Tanislav <[email protected]>");
+MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver");
+MODULE_LICENSE("GPL");
--
2.36.1


2022-06-28 12:46:47

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v6 2/2] iio: adc: ad4130: add AD4130 driver

On Tue, Jun 28, 2022 at 9:08 AM Cosmin Tanislav <[email protected]> wrote:
>
> AD4130-8 is an ultra-low power, high precision, measurement solution for
> low bandwidth battery operated applications.
>
> The fully integrated AFE (Analog Front-End) includes a multiplexer for up
> to 16 single-ended or 8 differential inputs, PGA (Programmable Gain
> Amplifier), 24-bit Sigma-Delta ADC, on-chip reference and oscillator,
> selectable filter options, smart sequencer, sensor biasing and excitation
> options, diagnostics, and a FIFO buffer.

Reviewed-by: Andy Shevchenko <[email protected]>

I think it's in a good enough shape, but the version of the ABI should
be bumped to 5.20. I think Jonathan may tweak it when applying if
neither requires to resend, otherwise, please update in next version.

> Signed-off-by: Cosmin Tanislav <[email protected]>
> ---
> .../ABI/testing/sysfs-bus-iio-adc-ad4130 | 36 +
> MAINTAINERS | 8 +
> drivers/iio/adc/Kconfig | 13 +
> drivers/iio/adc/Makefile | 1 +
> drivers/iio/adc/ad4130.c | 2014 +++++++++++++++++
> 5 files changed, 2072 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
> create mode 100644 drivers/iio/adc/ad4130.c
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130 b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
> new file mode 100644
> index 000000000000..90aa50cecfd1
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
> @@ -0,0 +1,36 @@
> +What: /sys/bus/iio/devices/iio:deviceX/in_voltage-voltage_filter_mode_available
> +KernelVersion: 5.19
> +Contact: [email protected]
> +Description:
> + Reading returns a list with the possible filter modes.
> + "sinc4" - Sinc 4. Excellent noise performance. Long 1st
> + conversion time. No natural 50/60Hz rejection.
> + "sinc4+sinc1" - Sinc4 + averaging by 8. Low 1st conversion time.
> + "sinc3" - Sinc3. Moderate 1st conversion time. Good noise
> + performance.
> + "sinc3+rej60" - Sinc3 + 60Hz rejection. At a sampling frequency
> + of 50Hz, achieves simultaneous 50Hz and 60Hz
> + rejection.
> + "sinc3+sinc1" - Sinc3 + averaging by 8. Low 1st conversion time.
> + Best used with a sampling frequency of at least
> + 216.19Hz.
> + "sinc3+pf1" - Sinc3 + Post Filter 1.
> + 53dB rejection @ 50Hz, 58dB rejection @ 60Hz.
> + "sinc3+pf2" - Sinc3 + Post Filter 2.
> + 70dB rejection @ 50Hz, 70dB rejection @ 60Hz.
> + "sinc3+pf3" - Sinc3 + Post Filter 3.
> + 99dB rejection @ 50Hz, 103dB rejection @ 60Hz.
> + "sinc3+pf4" - Sinc3 + Post Filter 4.
> + 103dB rejection @ 50Hz, 109dB rejection @ 60Hz.
> +
> +What: /sys/bus/iio/devices/iio:deviceX/in_voltageY-voltageZ_filter_mode
> +KernelVersion: 5.19
> +Contact: [email protected]
> +Description:
> + Set the filter mode of the differential channel. When the filter
> + mode changes, the in_voltageY-voltageZ_sampling_frequency and
> + in_voltageY-voltageZ_sampling_frequency_available attributes
> + might also change to accommodate the new filter mode.
> + If the current sampling frequency is out of range for the new
> + filter mode, the sampling frequency will be changed to the
> + closest valid one.
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a6d3bd9d2a8d..2981968260be 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1074,6 +1074,14 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git
> T: git git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
> F: drivers/net/amt.c
>
> +ANALOG DEVICES INC AD4130 DRIVER
> +M: Cosmin Tanislav <[email protected]>
> +L: [email protected]
> +S: Supported
> +W: http://ez.analog.com/community/linux-device-drivers
> +F: Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
> +F: drivers/iio/adc/ad4130.c
> +
> ANALOG DEVICES INC AD7192 DRIVER
> M: Alexandru Tachici <[email protected]>
> L: [email protected]
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index 7fe5930891e0..52387925e41f 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -21,6 +21,19 @@ config AD_SIGMA_DELTA
> select IIO_BUFFER
> select IIO_TRIGGERED_BUFFER
>
> +config AD4130
> + tristate "Analog Device AD4130 ADC Driver"
> + depends on SPI
> + select IIO_BUFFER
> + select IIO_KFIFO_BUF
> + select REGMAP_SPI
> + help
> + Say yes here to build support for Analog Devices AD4130-8 SPI analog
> + to digital converters (ADC).
> +
> + To compile this driver as a module, choose M here: the module will be
> + called ad4130.
> +
> config AD7091R5
> tristate "Analog Devices AD7091R5 ADC Driver"
> depends on I2C
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> index 1772a549a3c8..9d8619753b39 100644
> --- a/drivers/iio/adc/Makefile
> +++ b/drivers/iio/adc/Makefile
> @@ -6,6 +6,7 @@
> # When adding new entries keep the list in alphabetical order
> 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-$(CONFIG_AD7124) += ad7124.o
> obj-$(CONFIG_AD7192) += ad7192.o
> diff --git a/drivers/iio/adc/ad4130.c b/drivers/iio/adc/ad4130.c
> new file mode 100644
> index 000000000000..b907f8b8eec8
> --- /dev/null
> +++ b/drivers/iio/adc/ad4130.c
> @@ -0,0 +1,2014 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2022 Analog Devices, Inc.
> + * Author: Cosmin Tanislav <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/spi/spi.h>
> +#include <linux/units.h>
> +
> +#include <asm/div64.h>
> +#include <asm/unaligned.h>
> +
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/kfifo_buf.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define AD4130_NAME "ad4130"
> +
> +#define AD4130_COMMS_READ_MASK BIT(6)
> +
> +#define AD4130_STATUS_REG 0x00
> +#define AD4130_STATUS_POR_FLAG_MASK BIT(4)
> +
> +#define AD4130_ADC_CONTROL_REG 0x01
> +#define AD4130_ADC_CONTROL_BIPOLAR_MASK BIT(14)
> +#define AD4130_ADC_CONTROL_INT_REF_VAL_MASK BIT(13)
> +#define AD4130_INT_REF_2_5V 2500000
> +#define AD4130_INT_REF_1_25V 1250000
> +#define AD4130_ADC_CONTROL_CSB_EN_MASK BIT(9)
> +#define AD4130_ADC_CONTROL_INT_REF_EN_MASK BIT(8)
> +#define AD4130_ADC_CONTROL_MODE_MASK GENMASK(5, 2)
> +#define AD4130_ADC_CONTROL_MCLK_SEL_MASK GENMASK(1, 0)
> +#define AD4130_MCLK_FREQ_76_8KHZ 76800
> +#define AD4130_MCLK_FREQ_153_6KHZ 153600
> +
> +#define AD4130_DATA_REG 0x02
> +
> +#define AD4130_IO_CONTROL_REG 0x03
> +#define AD4130_IO_CONTROL_INT_PIN_SEL_MASK GENMASK(9, 8)
> +#define AD4130_IO_CONTROL_GPIO_DATA_MASK GENMASK(7, 4)
> +#define AD4130_IO_CONTROL_GPIO_CTRL_MASK GENMASK(3, 0)
> +
> +#define AD4130_VBIAS_REG 0x04
> +
> +#define AD4130_ID_REG 0x05
> +
> +#define AD4130_ERROR_REG 0x06
> +
> +#define AD4130_ERROR_EN_REG 0x07
> +
> +#define AD4130_MCLK_COUNT_REG 0x08
> +
> +#define AD4130_CHANNEL_X_REG(x) (0x09 + (x))
> +#define AD4130_CHANNEL_EN_MASK BIT(23)
> +#define AD4130_CHANNEL_SETUP_MASK GENMASK(22, 20)
> +#define AD4130_CHANNEL_AINP_MASK GENMASK(17, 13)
> +#define AD4130_CHANNEL_AINM_MASK GENMASK(12, 8)
> +#define AD4130_CHANNEL_IOUT1_MASK GENMASK(7, 4)
> +#define AD4130_CHANNEL_IOUT2_MASK GENMASK(3, 0)
> +
> +#define AD4130_CONFIG_X_REG(x) (0x19 + (x))
> +#define AD4130_CONFIG_IOUT1_VAL_MASK GENMASK(15, 13)
> +#define AD4130_CONFIG_IOUT2_VAL_MASK GENMASK(12, 10)
> +#define AD4130_CONFIG_BURNOUT_MASK GENMASK(9, 8)
> +#define AD4130_CONFIG_REF_BUFP_MASK BIT(7)
> +#define AD4130_CONFIG_REF_BUFM_MASK BIT(6)
> +#define AD4130_CONFIG_REF_SEL_MASK GENMASK(5, 4)
> +#define AD4130_CONFIG_PGA_MASK GENMASK(3, 1)
> +
> +#define AD4130_FILTER_X_REG(x) (0x21 + (x))
> +#define AD4130_FILTER_MODE_MASK GENMASK(15, 12)
> +#define AD4130_FILTER_SELECT_MASK GENMASK(10, 0)
> +#define AD4130_FILTER_SELECT_MIN 1
> +
> +#define AD4130_OFFSET_X_REG(x) (0x29 + (x))
> +
> +#define AD4130_GAIN_X_REG(x) (0x31 + (x))
> +
> +#define AD4130_MISC_REG 0x39
> +
> +#define AD4130_FIFO_CONTROL_REG 0x3a
> +#define AD4130_FIFO_CONTROL_HEADER_MASK BIT(18)
> +#define AD4130_FIFO_CONTROL_MODE_MASK GENMASK(17, 16)
> +#define AD4130_FIFO_CONTROL_WM_INT_EN_MASK BIT(9)
> +#define AD4130_FIFO_CONTROL_WM_MASK GENMASK(7, 0)
> +#define AD4130_WATERMARK_256 0
> +
> +#define AD4130_FIFO_STATUS_REG 0x3b
> +
> +#define AD4130_FIFO_THRESHOLD_REG 0x3c
> +
> +#define AD4130_FIFO_DATA_REG 0x3d
> +#define AD4130_FIFO_SIZE 256
> +#define AD4130_FIFO_MAX_SAMPLE_SIZE 3
> +
> +#define AD4130_MAX_ANALOG_PINS 16
> +#define AD4130_MAX_CHANNELS 16
> +#define AD4130_MAX_DIFF_INPUTS 30
> +#define AD4130_MAX_GPIOS 4
> +#define AD4130_MAX_ODR 2400
> +#define AD4130_MAX_PGA 8
> +#define AD4130_MAX_SETUPS 8
> +
> +#define AD4130_AIN2_P1 0x2
> +#define AD4130_AIN3_P2 0x3
> +
> +#define AD4130_RESET_BUF_SIZE 8
> +#define AD4130_RESET_SLEEP_US (160 * MICRO / AD4130_MCLK_FREQ_76_8KHZ)
> +
> +#define AD4130_INVALID_SLOT -1
> +
> +static const unsigned int ad4130_reg_size[] = {
> + [AD4130_STATUS_REG] = 1,
> + [AD4130_ADC_CONTROL_REG] = 2,
> + [AD4130_DATA_REG] = 3,
> + [AD4130_IO_CONTROL_REG] = 2,
> + [AD4130_VBIAS_REG] = 2,
> + [AD4130_ID_REG] = 1,
> + [AD4130_ERROR_REG] = 2,
> + [AD4130_ERROR_EN_REG] = 2,
> + [AD4130_MCLK_COUNT_REG] = 1,
> + [AD4130_CHANNEL_X_REG(0) ... AD4130_CHANNEL_X_REG(AD4130_MAX_CHANNELS)] = 3,
> + [AD4130_CONFIG_X_REG(0) ... AD4130_CONFIG_X_REG(AD4130_MAX_SETUPS)] = 2,
> + [AD4130_FILTER_X_REG(0) ... AD4130_FILTER_X_REG(AD4130_MAX_SETUPS)] = 3,
> + [AD4130_OFFSET_X_REG(0) ... AD4130_OFFSET_X_REG(AD4130_MAX_SETUPS)] = 3,
> + [AD4130_GAIN_X_REG(0) ... AD4130_GAIN_X_REG(AD4130_MAX_SETUPS)] = 3,
> + [AD4130_MISC_REG] = 2,
> + [AD4130_FIFO_CONTROL_REG] = 3,
> + [AD4130_FIFO_STATUS_REG] = 1,
> + [AD4130_FIFO_THRESHOLD_REG] = 3,
> + [AD4130_FIFO_DATA_REG] = 3,
> +};
> +
> +enum ad4130_id {
> + ID_AD4130_8_24_WLCSP,
> + ID_AD4130_8_24_LFCSP,
> + ID_AD4130_8_16_WLCSP,
> + ID_AD4130_8_16_LFCSP,
> +};
> +
> +enum ad4130_int_ref_val {
> + AD4130_INT_REF_VAL_2_5V,
> + AD4130_INT_REF_VAL_1_25V,
> +};
> +
> +enum ad4130_mclk_sel {
> + AD4130_MCLK_76_8KHZ,
> + AD4130_MCLK_76_8KHZ_OUT,
> + AD4130_MCLK_76_8KHZ_EXT,
> + AD4130_MCLK_153_6KHZ_EXT,
> + AD4130_MCLK_SEL_MAX
> +};
> +
> +enum ad4130_int_pin_sel {
> + AD4130_INT_PIN_INT,
> + AD4130_INT_PIN_CLK,
> + AD4130_INT_PIN_P2,
> + AD4130_INT_PIN_DOUT,
> +};
> +
> +enum ad4130_iout {
> + AD4130_IOUT_OFF,
> + AD4130_IOUT_10000NA,
> + AD4130_IOUT_20000NA,
> + AD4130_IOUT_50000NA,
> + AD4130_IOUT_100000NA,
> + AD4130_IOUT_150000NA,
> + AD4130_IOUT_200000NA,
> + AD4130_IOUT_100NA,
> + AD4130_IOUT_MAX
> +};
> +
> +enum ad4130_burnout {
> + AD4130_BURNOUT_OFF,
> + AD4130_BURNOUT_500NA,
> + AD4130_BURNOUT_2000NA,
> + AD4130_BURNOUT_4000NA,
> + AD4130_BURNOUT_MAX
> +};
> +
> +enum ad4130_ref_sel {
> + AD4130_REF_REFIN1,
> + AD4130_REF_REFIN2,
> + AD4130_REF_REFOUT_AVSS,
> + AD4130_REF_AVDD_AVSS,
> + AD4130_REF_SEL_MAX
> +};
> +
> +enum ad4130_fifo_mode {
> + AD4130_FIFO_MODE_DISABLED = 0b00,
> + AD4130_FIFO_MODE_WM = 0b01,
> +};
> +
> +enum ad4130_mode {
> + AD4130_MODE_CONTINUOUS = 0b0000,
> + AD4130_MODE_IDLE = 0b0100,
> +};
> +
> +enum ad4130_filter_mode {
> + AD4130_FILTER_SINC4,
> + AD4130_FILTER_SINC4_SINC1,
> + AD4130_FILTER_SINC3,
> + AD4130_FILTER_SINC3_REJ60,
> + AD4130_FILTER_SINC3_SINC1,
> + AD4130_FILTER_SINC3_PF1,
> + AD4130_FILTER_SINC3_PF2,
> + AD4130_FILTER_SINC3_PF3,
> + AD4130_FILTER_SINC3_PF4,
> +};
> +
> +enum ad4130_pin_function {
> + AD4130_PIN_FN_NONE,
> + AD4130_PIN_FN_SPECIAL = BIT(0),
> + AD4130_PIN_FN_DIFF = BIT(1),
> + AD4130_PIN_FN_EXCITATION = BIT(2),
> + AD4130_PIN_FN_VBIAS = BIT(3),
> +};
> +
> +struct ad4130_setup_info {
> + unsigned int iout0_val;
> + unsigned int iout1_val;
> + unsigned int burnout;
> + unsigned int pga;
> + unsigned int fs;
> + u32 ref_sel;
> + enum ad4130_filter_mode filter_mode;
> + bool ref_bufp;
> + bool ref_bufm;
> +};
> +
> +struct ad4130_slot_info {
> + struct ad4130_setup_info setup;
> + unsigned int enabled_channels;
> + unsigned int channels;
> +};
> +
> +struct ad4130_chan_info {
> + struct ad4130_setup_info setup;
> + u32 iout0;
> + u32 iout1;
> + int slot;
> + bool enabled;
> + bool initialized;
> +};
> +
> +struct ad4130_filter_config {
> + enum ad4130_filter_mode filter_mode;
> + unsigned int odr_div;
> + unsigned int fs_max;
> + enum iio_available_type samp_freq_avail_type;
> + int samp_freq_avail_len;
> + int samp_freq_avail[3][2];
> +};
> +
> +struct ad4130_state {
> + struct regmap *regmap;
> + struct spi_device *spi;
> + struct clk *mclk;
> + struct regulator_bulk_data regulators[4];
> + u32 irq_trigger;
> + u32 inv_irq_trigger;
> +
> + /*
> + * Synchronize access to members the of driver state, and ensure
> + * atomicity of consecutive regmap operations.
> + */
> + struct mutex lock;
> + struct completion completion;
> +
> + struct iio_chan_spec chans[AD4130_MAX_CHANNELS];
> + struct ad4130_chan_info chans_info[AD4130_MAX_CHANNELS];
> + struct ad4130_slot_info slots_info[AD4130_MAX_SETUPS];
> + enum ad4130_pin_function pins_fn[AD4130_MAX_ANALOG_PINS];
> + u32 vbias_pins[AD4130_MAX_ANALOG_PINS];
> + u32 num_vbias_pins;
> + int scale_tbls[AD4130_REF_SEL_MAX][AD4130_MAX_PGA][2];
> + struct gpio_chip gc;
> +
> + u32 int_pin_sel;
> + u32 int_ref_uv;
> + u32 mclk_sel;
> + bool int_ref_en;
> + bool bipolar;
> +
> + unsigned int num_enabled_channels;
> + unsigned int effective_watermark;
> + unsigned int watermark;
> +
> + struct spi_message fifo_msg;
> + struct spi_transfer fifo_xfer[2];
> +
> + /*
> + * DMA (thus cache coherency maintenance) requires any transfer
> + * buffers to live in their own cache lines. As the use of these
> + * buffers is synchronous, all of the buffers used for DMA in this
> + * driver may share a cache line.
> + */
> + u8 reset_buf[AD4130_RESET_BUF_SIZE] __aligned(IIO_DMA_MINALIGN);
> + u8 reg_write_tx_buf[4];
> + u8 reg_read_tx_buf[1];
> + u8 reg_read_rx_buf[3];
> + u8 fifo_tx_buf[2];
> + u8 fifo_rx_buf[AD4130_FIFO_SIZE *
> + AD4130_FIFO_MAX_SAMPLE_SIZE];
> +};
> +
> +static const char * const ad4130_int_pin_names[] = {
> + [AD4130_INT_PIN_INT] = "int",
> + [AD4130_INT_PIN_CLK] = "clk",
> + [AD4130_INT_PIN_P2] = "p2",
> + [AD4130_INT_PIN_DOUT] = "dout",
> +};
> +
> +static const unsigned int ad4130_iout_current_na_tbl[AD4130_IOUT_MAX] = {
> + [AD4130_IOUT_OFF] = 0,
> + [AD4130_IOUT_100NA] = 100,
> + [AD4130_IOUT_10000NA] = 10000,
> + [AD4130_IOUT_20000NA] = 20000,
> + [AD4130_IOUT_50000NA] = 50000,
> + [AD4130_IOUT_100000NA] = 100000,
> + [AD4130_IOUT_150000NA] = 150000,
> + [AD4130_IOUT_200000NA] = 200000,
> +};
> +
> +static const unsigned int ad4130_burnout_current_na_tbl[AD4130_BURNOUT_MAX] = {
> + [AD4130_BURNOUT_OFF] = 0,
> + [AD4130_BURNOUT_500NA] = 500,
> + [AD4130_BURNOUT_2000NA] = 2000,
> + [AD4130_BURNOUT_4000NA] = 4000,
> +};
> +
> +#define AD4130_VARIABLE_ODR_CONFIG(_filter_mode, _odr_div, _fs_max) \
> +{ \
> + .filter_mode = (_filter_mode), \
> + .odr_div = (_odr_div), \
> + .fs_max = (_fs_max), \
> + .samp_freq_avail_type = IIO_AVAIL_RANGE, \
> + .samp_freq_avail = { \
> + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \
> + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \
> + { AD4130_MAX_ODR, (_odr_div) }, \
> + }, \
> +}
> +
> +#define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div) \
> +{ \
> + .filter_mode = (_filter_mode), \
> + .odr_div = (_odr_div), \
> + .fs_max = AD4130_FILTER_SELECT_MIN, \
> + .samp_freq_avail_type = IIO_AVAIL_LIST, \
> + .samp_freq_avail_len = 1, \
> + .samp_freq_avail = { \
> + { AD4130_MAX_ODR, (_odr_div) }, \
> + }, \
> +}
> +
> +static const struct ad4130_filter_config ad4130_filter_configs[] = {
> + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4, 1, 10),
> + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10),
> + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3, 1, 2047),
> + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1, 2047),
> + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047),
> + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1, 92),
> + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2, 100),
> + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3, 124),
> + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4, 148),
> +};
> +
> +static const char * const ad4130_filter_modes_str[] = {
> + [AD4130_FILTER_SINC4] = "sinc4",
> + [AD4130_FILTER_SINC4_SINC1] = "sinc4+sinc1",
> + [AD4130_FILTER_SINC3] = "sinc3",
> + [AD4130_FILTER_SINC3_REJ60] = "sinc3+rej60",
> + [AD4130_FILTER_SINC3_SINC1] = "sinc3+sinc1",
> + [AD4130_FILTER_SINC3_PF1] = "sinc3+pf1",
> + [AD4130_FILTER_SINC3_PF2] = "sinc3+pf2",
> + [AD4130_FILTER_SINC3_PF3] = "sinc3+pf3",
> + [AD4130_FILTER_SINC3_PF4] = "sinc3+pf4",
> +};
> +
> +static int ad4130_get_reg_size(struct ad4130_state *st, unsigned int reg,
> + unsigned int *size)
> +{
> + if (reg >= ARRAY_SIZE(ad4130_reg_size))
> + return -EINVAL;
> +
> + *size = ad4130_reg_size[reg];
> +
> + return 0;
> +}
> +
> +static unsigned int ad4130_data_reg_size(struct ad4130_state *st)
> +{
> + unsigned int data_reg_size;
> + int ret;
> +
> + ret = ad4130_get_reg_size(st, AD4130_DATA_REG, &data_reg_size);
> + if (ret)
> + return 0;
> +
> + return data_reg_size;
> +}
> +
> +static unsigned int ad4130_resolution(struct ad4130_state *st)
> +{
> + return ad4130_data_reg_size(st) * BITS_PER_BYTE;
> +}
> +
> +static int ad4130_reg_write(void *context, unsigned int reg, unsigned int val)
> +{
> + struct ad4130_state *st = context;
> + unsigned int size;
> + int ret;
> +
> + ret = ad4130_get_reg_size(st, reg, &size);
> + if (ret)
> + return ret;
> +
> + st->reg_write_tx_buf[0] = reg;
> +
> + switch (size) {
> + case 3:
> + put_unaligned_be24(val, &st->reg_write_tx_buf[1]);
> + break;
> + case 2:
> + put_unaligned_be16(val, &st->reg_write_tx_buf[1]);
> + break;
> + case 1:
> + st->reg_write_tx_buf[1] = val;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return spi_write(st->spi, st->reg_write_tx_buf, size + 1);
> +}
> +
> +static int ad4130_reg_read(void *context, unsigned int reg, unsigned int *val)
> +{
> + struct ad4130_state *st = context;
> + struct spi_transfer t[] = {
> + {
> + .tx_buf = st->reg_read_tx_buf,
> + .len = sizeof(st->reg_read_tx_buf),
> + },
> + {
> + .rx_buf = st->reg_read_rx_buf,
> + },
> + };
> + unsigned int size;
> + int ret;
> +
> + ret = ad4130_get_reg_size(st, reg, &size);
> + if (ret)
> + return ret;
> +
> + st->reg_read_tx_buf[0] = AD4130_COMMS_READ_MASK | reg;
> + t[1].len = size;
> +
> + ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
> + if (ret)
> + return ret;
> +
> + switch (size) {
> + case 3:
> + *val = get_unaligned_be24(st->reg_read_rx_buf);
> + break;
> + case 2:
> + *val = get_unaligned_be16(st->reg_read_rx_buf);
> + break;
> + case 1:
> + *val = st->reg_read_rx_buf[0];
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static const struct regmap_config ad4130_regmap_config = {
> + .reg_read = ad4130_reg_read,
> + .reg_write = ad4130_reg_write,
> +};
> +
> +static int ad4130_gpio_init_valid_mask(struct gpio_chip *gc,
> + unsigned long *valid_mask,
> + unsigned int ngpios)
> +{
> + struct ad4130_state *st = gpiochip_get_data(gc);
> + unsigned int i;
> +
> + /*
> + * Output-only GPIO functionality is available on pins AIN2 through
> + * AIN5. If these pins are used for anything else, do not expose them.
> + */
> + for (i = 0; i < ngpios; i++) {
> + unsigned int pin = i + AD4130_AIN2_P1;
> + bool valid = st->pins_fn[pin] == AD4130_PIN_FN_NONE;
> +
> + __assign_bit(i, valid_mask, valid);
> + }
> +
> +
> + return 0;
> +}
> +
> +static int ad4130_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
> +{
> + return GPIO_LINE_DIRECTION_OUT;
> +}
> +
> +static void ad4130_gpio_set(struct gpio_chip *gc, unsigned int offset,
> + int value)
> +{
> + struct ad4130_state *st = gpiochip_get_data(gc);
> + unsigned int mask = FIELD_PREP(AD4130_IO_CONTROL_GPIO_DATA_MASK,
> + BIT(offset));
> +
> + regmap_update_bits(st->regmap, AD4130_IO_CONTROL_REG, mask,
> + value ? mask : 0);
> +}
> +
> +static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode)
> +{
> + return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
> + AD4130_ADC_CONTROL_MODE_MASK,
> + FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, mode));
> +}
> +
> +static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en)
> +{
> + return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
> + AD4130_FIFO_CONTROL_WM_INT_EN_MASK,
> + FIELD_PREP(AD4130_FIFO_CONTROL_WM_INT_EN_MASK, en));
> +}
> +
> +static unsigned int ad4130_watermark_reg_val(unsigned int val)
> +{
> + if (val == AD4130_FIFO_SIZE)
> + val = AD4130_WATERMARK_256;
> +
> + return val;
> +}
> +
> +static int ad4130_set_fifo_mode(struct ad4130_state *st,
> + enum ad4130_fifo_mode mode)
> +{
> + return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
> + AD4130_FIFO_CONTROL_MODE_MASK,
> + FIELD_PREP(AD4130_FIFO_CONTROL_MODE_MASK, mode));
> +}
> +
> +static void ad4130_push_fifo_data(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int data_reg_size = ad4130_data_reg_size(st);
> + unsigned int transfer_len = st->effective_watermark * data_reg_size;
> + unsigned int set_size = st->num_enabled_channels * data_reg_size;
> + unsigned int i;
> + int ret;
> +
> + st->fifo_tx_buf[1] = ad4130_watermark_reg_val(st->effective_watermark);
> + st->fifo_xfer[1].len = transfer_len;
> +
> + ret = spi_sync(st->spi, &st->fifo_msg);
> + if (ret)
> + return;
> +
> + for (i = 0; i < transfer_len; i += set_size)
> + iio_push_to_buffers(indio_dev, &st->fifo_rx_buf[i]);
> +}
> +
> +static irqreturn_t ad4130_irq_handler(int irq, void *private)
> +{
> + struct iio_dev *indio_dev = private;
> + struct ad4130_state *st = iio_priv(indio_dev);
> +
> + if (iio_buffer_enabled(indio_dev))
> + ad4130_push_fifo_data(indio_dev);
> + else
> + complete(&st->completion);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int ad4130_find_slot(struct ad4130_state *st,
> + struct ad4130_setup_info *target_setup_info,
> + unsigned int *slot, bool *overwrite)
> +{
> + unsigned int i;
> +
> + *slot = AD4130_INVALID_SLOT;
> + *overwrite = false;
> +
> + for (i = 0; i < AD4130_MAX_SETUPS; i++) {
> + struct ad4130_slot_info *slot_info = &st->slots_info[i];
> +
> + /* Immediately accept a matching setup info. */
> + if (!memcmp(target_setup_info, &slot_info->setup,
> + sizeof(*target_setup_info))) {
> + *slot = i;
> + return 0;
> + }
> +
> + /* Ignore all setups which are used by enabled channels. */
> + if (slot_info->enabled_channels)
> + continue;
> +
> + /* Find the least used slot. */
> + if (*slot == AD4130_INVALID_SLOT ||
> + slot_info->channels < st->slots_info[*slot].channels)
> + *slot = i;
> + }
> +
> + if (*slot == AD4130_INVALID_SLOT)
> + return -EINVAL;
> +
> + *overwrite = true;
> +
> + return 0;
> +}
> +
> +static void ad4130_unlink_channel(struct ad4130_state *st, unsigned int channel)
> +{
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_slot_info *slot_info = &st->slots_info[chan_info->slot];
> +
> + chan_info->slot = AD4130_INVALID_SLOT;
> + slot_info->channels--;
> +}
> +
> +static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < AD4130_MAX_CHANNELS; i++) {
> + struct ad4130_chan_info *chan_info = &st->chans_info[i];
> +
> + if (!chan_info->initialized || chan_info->slot != slot)
> + continue;
> +
> + ad4130_unlink_channel(st, i);
> + }
> +
> + return 0;
> +}
> +
> +static int ad4130_link_channel_slot(struct ad4130_state *st,
> + unsigned int channel, unsigned int slot)
> +{
> + struct ad4130_slot_info *slot_info = &st->slots_info[slot];
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + int ret;
> +
> + ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
> + AD4130_CHANNEL_SETUP_MASK,
> + FIELD_PREP(AD4130_CHANNEL_SETUP_MASK, slot));
> + if (ret)
> + return ret;
> +
> + chan_info->slot = slot;
> + slot_info->channels++;
> +
> + return 0;
> +}
> +
> +static int ad4130_write_slot_setup(struct ad4130_state *st,
> + unsigned int slot,
> + struct ad4130_setup_info *setup_info)
> +{
> + unsigned int val;
> + int ret;
> +
> + val = FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout0_val) |
> + FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout1_val) |
> + FIELD_PREP(AD4130_CONFIG_BURNOUT_MASK, setup_info->burnout) |
> + FIELD_PREP(AD4130_CONFIG_REF_BUFP_MASK, setup_info->ref_bufp) |
> + FIELD_PREP(AD4130_CONFIG_REF_BUFM_MASK, setup_info->ref_bufm) |
> + FIELD_PREP(AD4130_CONFIG_REF_SEL_MASK, setup_info->ref_sel) |
> + FIELD_PREP(AD4130_CONFIG_PGA_MASK, setup_info->pga);
> +
> + ret = regmap_write(st->regmap, AD4130_CONFIG_X_REG(slot), val);
> + if (ret)
> + return ret;
> +
> + val = FIELD_PREP(AD4130_FILTER_MODE_MASK, setup_info->filter_mode) |
> + FIELD_PREP(AD4130_FILTER_SELECT_MASK, setup_info->fs);
> +
> + ret = regmap_write(st->regmap, AD4130_FILTER_X_REG(slot), val);
> + if (ret)
> + return ret;
> +
> + memcpy(&st->slots_info[slot].setup, setup_info, sizeof(*setup_info));
> +
> + return 0;
> +}
> +
> +static int ad4130_write_channel_setup(struct ad4130_state *st,
> + unsigned int channel, bool on_enable)
> +{
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_setup_info *setup_info = &chan_info->setup;
> + bool overwrite;
> + int slot;
> + int ret;
> +
> + /*
> + * The following cases need to be handled.
> + *
> + * 1. Enabled and linked channel with setup changes:
> + * - Find a slot. If not possible, return error.
> + * - Unlink channel from current slot.
> + * - If the slot has channels linked to it, unlink all channels, and
> + * write the new setup to it.
> + * - Link channel to new slot.
> + *
> + * 2. Soon to be enabled and unlinked channel:
> + * - Find a slot. If not possible, return error.
> + * - If the slot has channels linked to it, unlink all channels, and
> + * write the new setup to it.
> + * - Link channel to the slot.
> + *
> + * 3. Disabled and linked channel with setup changes:
> + * - Unlink channel from current slot.
> + *
> + * 4. Soon to be enabled and linked channel:
> + * 5. Disabled and unlinked channel with setup changes:
> + * - Do nothing.
> + */
> +
> + /* Case 4 */
> + if (on_enable && chan_info->slot != AD4130_INVALID_SLOT)
> + return 0;
> +
> + if (!on_enable && !chan_info->enabled) {
> + if (chan_info->slot != AD4130_INVALID_SLOT)
> + /* Case 3 */
> + ad4130_unlink_channel(st, channel);
> +
> + /* Cases 3 & 5 */
> + return 0;
> + }
> +
> + /* Cases 1 & 2 */
> + ret = ad4130_find_slot(st, setup_info, &slot, &overwrite);
> + if (ret)
> + return ret;
> +
> + if (chan_info->slot != AD4130_INVALID_SLOT)
> + /* Case 1 */
> + ad4130_unlink_channel(st, channel);
> +
> + if (overwrite) {
> + ret = ad4130_unlink_slot(st, slot);
> + if (ret)
> + return ret;
> +
> + ret = ad4130_write_slot_setup(st, slot, setup_info);
> + if (ret)
> + return ret;
> + }
> +
> + return ad4130_link_channel_slot(st, channel, slot);
> +}
> +
> +static int ad4130_set_channel_enable(struct ad4130_state *st,
> + unsigned int channel, bool status)
> +{
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_slot_info *slot_info;
> + int ret;
> +
> + if (chan_info->enabled == status)
> + return 0;
> +
> + if (status) {
> + ret = ad4130_write_channel_setup(st, channel, true);
> + if (ret)
> + return ret;
> + }
> +
> + slot_info = &st->slots_info[chan_info->slot];
> +
> + ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
> + AD4130_CHANNEL_EN_MASK,
> + FIELD_PREP(AD4130_CHANNEL_EN_MASK, status));
> + if (ret)
> + return ret;
> +
> + slot_info->enabled_channels += status ? 1 : -1;
> + chan_info->enabled = status;
> +
> + return 0;
> +}
> +
> +/*
> + * Table 58. FILTER_MODE_n bits and Filter Types of the datasheet describes
> + * the relation between filter mode, ODR and FS.
> + *
> + * Notice that the max ODR of each filter mode is not necessarily the
> + * absolute max ODR supported by the chip.
> + *
> + * The ODR divider is not explicitly specified, but it can be deduced based
> + * on the ODR range of each filter mode.
> + *
> + * For example, for Sinc4+Sinc1, max ODR is 218.18. That means that the
> + * absolute max ODR is divided by 11 to achieve the max ODR of this filter
> + * mode.
> + *
> + * The formulas for converting between ODR and FS for a specific filter
> + * mode can be deduced from the same table.
> + *
> + * Notice that FS = 1 actually means max ODR, and that ODR decreases by
> + * (maximum ODR / maximum FS) for each increment of FS.
> + *
> + * odr = MAX_ODR / odr_div * (1 - (fs - 1) / fs_max) <=>
> + * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
> + * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
> + * odr = MAX_ODR * (fs_max - fs + 1) / (fs_max * odr_div)
> + * (used in ad4130_fs_to_freq)
> + *
> + * For the opposite formula, FS can be extracted from the last one.
> + *
> + * MAX_ODR * (fs_max - fs + 1) = fs_max * odr_div * odr <=>
> + * fs_max - fs + 1 = fs_max * odr_div * odr / MAX_ODR <=>
> + * fs = 1 + fs_max - fs_max * odr_div * odr / MAX_ODR
> + * (used in ad4130_fs_to_freq)
> + */
> +
> +static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode,
> + int val, int val2, unsigned int *fs)
> +{
> + const struct ad4130_filter_config *filter_config =
> + &ad4130_filter_configs[filter_mode];
> + u64 dividend, divisor;
> + int temp;
> +
> + dividend = filter_config->fs_max * filter_config->odr_div *
> + ((u64)val * NANO + val2);
> + divisor = (u64)AD4130_MAX_ODR * NANO;
> +
> + temp = AD4130_FILTER_SELECT_MIN + filter_config->fs_max -
> + DIV64_U64_ROUND_CLOSEST(dividend, divisor);
> +
> + if (temp < AD4130_FILTER_SELECT_MIN)
> + temp = AD4130_FILTER_SELECT_MIN;
> + else if (temp > filter_config->fs_max)
> + temp = filter_config->fs_max;
> +
> + *fs = temp;
> +}
> +
> +static void ad4130_fs_to_freq(enum ad4130_filter_mode filter_mode,
> + unsigned int fs, int *val, int *val2)
> +{
> + const struct ad4130_filter_config *filter_config =
> + &ad4130_filter_configs[filter_mode];
> + unsigned int dividend, divisor;
> + u64 temp;
> +
> + dividend = (filter_config->fs_max - fs + AD4130_FILTER_SELECT_MIN) *
> + AD4130_MAX_ODR;
> + divisor = filter_config->fs_max * filter_config->odr_div;
> +
> + temp = div_u64((u64)dividend * NANO, divisor);
> + *val = div_u64_rem(temp, NANO, val2);
> +}
> +
> +static int ad4130_set_filter_mode(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + unsigned int val)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel = chan->scan_index;
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_setup_info *setup_info = &chan_info->setup;
> + enum ad4130_filter_mode old_filter_mode;
> + int freq_val, freq_val2;
> + unsigned int old_fs;
> + int ret = 0;
> +
> + mutex_lock(&st->lock);
> + if (setup_info->filter_mode == val)
> + goto out;
> +
> + old_fs = setup_info->fs;
> + old_filter_mode = setup_info->filter_mode;
> +
> + /*
> + * When switching between filter modes, try to match the ODR as
> + * close as possible. To do this, convert the current FS into ODR
> + * using the old filter mode, then convert it back into FS using
> + * the new filter mode.
> + */
> + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
> + &freq_val, &freq_val2);
> +
> + ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs);
> +
> + setup_info->filter_mode = val;
> +
> + ret = ad4130_write_channel_setup(st, channel, false);
> + if (ret) {
> + setup_info->fs = old_fs;
> + setup_info->filter_mode = old_filter_mode;
> + }
> +
> + out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int ad4130_get_filter_mode(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel = chan->scan_index;
> + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
> + enum ad4130_filter_mode filter_mode;
> +
> + mutex_lock(&st->lock);
> + filter_mode = setup_info->filter_mode;
> + mutex_unlock(&st->lock);
> +
> + return filter_mode;
> +}
> +
> +static const struct iio_enum ad4130_filter_mode_enum = {
> + .items = ad4130_filter_modes_str,
> + .num_items = ARRAY_SIZE(ad4130_filter_modes_str),
> + .set = ad4130_set_filter_mode,
> + .get = ad4130_get_filter_mode,
> +};
> +
> +static const struct iio_chan_spec_ext_info ad4130_filter_mode_ext_info[] = {
> + IIO_ENUM("filter_mode", IIO_SEPARATE, &ad4130_filter_mode_enum),
> + IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_TYPE,
> + &ad4130_filter_mode_enum),
> + { }
> +};
> +
> +static const struct iio_chan_spec ad4130_channel_template = {
> + .type = IIO_VOLTAGE,
> + .indexed = 1,
> + .differential = 1,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE) |
> + BIT(IIO_CHAN_INFO_OFFSET) |
> + BIT(IIO_CHAN_INFO_SAMP_FREQ),
> + .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) |
> + BIT(IIO_CHAN_INFO_SAMP_FREQ),
> + .ext_info = ad4130_filter_mode_ext_info,
> + .scan_type = {
> + .sign = 'u',
> + .endianness = IIO_BE,
> + },
> +};
> +
> +static int ad4130_set_channel_pga(struct ad4130_state *st, unsigned int channel,
> + int val, int val2)
> +{
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_setup_info *setup_info = &chan_info->setup;
> + unsigned int pga, old_pga;
> + int ret = 0;
> +
> + for (pga = 0; pga < AD4130_MAX_PGA; pga++)
> + if (val == st->scale_tbls[setup_info->ref_sel][pga][0] &&
> + val2 == st->scale_tbls[setup_info->ref_sel][pga][1])
> + break;
> +
> + if (pga == AD4130_MAX_PGA)
> + return -EINVAL;
> +
> + mutex_lock(&st->lock);
> + if (pga == setup_info->pga)
> + goto out;
> +
> + old_pga = setup_info->pga;
> + setup_info->pga = pga;
> +
> + ret = ad4130_write_channel_setup(st, channel, false);
> + if (ret)
> + setup_info->pga = old_pga;
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int ad4130_set_channel_freq(struct ad4130_state *st,
> + unsigned int channel, int val, int val2)
> +{
> + struct ad4130_chan_info *chan_info = &st->chans_info[channel];
> + struct ad4130_setup_info *setup_info = &chan_info->setup;
> + unsigned int fs, old_fs;
> + int ret = 0;
> +
> + mutex_lock(&st->lock);
> + old_fs = setup_info->fs;
> +
> + ad4130_freq_to_fs(setup_info->filter_mode, val, val2, &fs);
> +
> + if (fs == setup_info->fs)
> + goto out;
> +
> + setup_info->fs = fs;
> +
> + ret = ad4130_write_channel_setup(st, channel, false);
> + if (ret)
> + setup_info->fs = old_fs;
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int _ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
> + int *val)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + ret = ad4130_set_channel_enable(st, channel, true);
> + if (ret)
> + return ret;
> +
> + reinit_completion(&st->completion);
> +
> + ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
> + if (ret)
> + return ret;
> +
> + ret = wait_for_completion_timeout(&st->completion,
> + msecs_to_jiffies(1000));
> + if (!ret)
> + return -ETIMEDOUT;
> +
> + ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(st->regmap, AD4130_DATA_REG, val);
> + if (ret)
> + return ret;
> +
> + ret = ad4130_set_channel_enable(st, channel, false);
> + if (ret)
> + return ret;
> +
> + return IIO_VAL_INT;
> +}
> +
> +static int ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
> + int *val)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + ret = iio_device_claim_direct_mode(indio_dev);
> + if (ret)
> + return ret;
> +
> + mutex_lock(&st->lock);
> + ret = _ad4130_read_sample(indio_dev, channel, val);
> + mutex_unlock(&st->lock);
> +
> + iio_device_release_direct_mode(indio_dev);
> +
> + return ret;
> +}
> +
> +static int ad4130_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long info)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel = chan->scan_index;
> + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
> +
> + switch (info) {
> + case IIO_CHAN_INFO_RAW:
> + return ad4130_read_sample(indio_dev, channel, val);
> + case IIO_CHAN_INFO_SCALE:
> + mutex_lock(&st->lock);
> + *val = st->scale_tbls[setup_info->ref_sel][setup_info->pga][0];
> + *val2 = st->scale_tbls[setup_info->ref_sel][setup_info->pga][1];
> + mutex_unlock(&st->lock);
> +
> + return IIO_VAL_INT_PLUS_NANO;
> + case IIO_CHAN_INFO_OFFSET:
> + *val = st->bipolar ? -BIT(chan->scan_type.realbits - 1) : 0;
> +
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + mutex_lock(&st->lock);
> + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
> + val, val2);
> + mutex_unlock(&st->lock);
> +
> + return IIO_VAL_INT_PLUS_NANO;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int ad4130_read_avail(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + const int **vals, int *type, int *length,
> + long info)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel = chan->scan_index;
> + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
> + const struct ad4130_filter_config *filter_config;
> +
> + switch (info) {
> + case IIO_CHAN_INFO_SCALE:
> + *vals = (int *)st->scale_tbls[setup_info->ref_sel];
> + *length = ARRAY_SIZE(st->scale_tbls[setup_info->ref_sel]) * 2;
> +
> + *type = IIO_VAL_INT_PLUS_NANO;
> +
> + return IIO_AVAIL_LIST;
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + mutex_lock(&st->lock);
> + filter_config = &ad4130_filter_configs[setup_info->filter_mode];
> + mutex_unlock(&st->lock);
> +
> + *vals = (int *)filter_config->samp_freq_avail;
> + *length = filter_config->samp_freq_avail_len * 2;
> + *type = IIO_VAL_FRACTIONAL;
> +
> + return filter_config->samp_freq_avail_type;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int ad4130_write_raw_get_fmt(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + long info)
> +{
> + switch (info) {
> + case IIO_CHAN_INFO_SCALE:
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + return IIO_VAL_INT_PLUS_NANO;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int ad4130_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long info)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel = chan->scan_index;
> +
> + switch (info) {
> + case IIO_CHAN_INFO_SCALE:
> + return ad4130_set_channel_pga(st, channel, val, val2);
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + return ad4130_set_channel_freq(st, channel, val, val2);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int ad4130_reg_access(struct iio_dev *indio_dev, unsigned int reg,
> + unsigned int writeval, unsigned int *readval)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> +
> + if (readval)
> + return regmap_read(st->regmap, reg, readval);
> +
> + return regmap_write(st->regmap, reg, writeval);
> +}
> +
> +static int ad4130_update_scan_mode(struct iio_dev *indio_dev,
> + const unsigned long *scan_mask)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int channel;
> + unsigned int val = 0;
> + int ret;
> +
> + mutex_lock(&st->lock);
> +
> + for_each_set_bit(channel, scan_mask, indio_dev->num_channels) {
> + ret = ad4130_set_channel_enable(st, channel, true);
> + if (ret)
> + goto out;
> +
> + val++;
> + }
> +
> + st->num_enabled_channels = val;
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return 0;
> +}
> +
> +static int ad4130_set_fifo_watermark(struct iio_dev *indio_dev, unsigned int val)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int eff;
> + int ret;
> +
> + if (val > AD4130_FIFO_SIZE)
> + return -EINVAL;
> +
> + eff = val * st->num_enabled_channels;
> + if (eff > AD4130_FIFO_SIZE)
> + /*
> + * Always set watermark to a multiple of the number of
> + * enabled channels to avoid making the FIFO unaligned.
> + */
> + eff = rounddown(AD4130_FIFO_SIZE, st->num_enabled_channels);
> +
> + mutex_lock(&st->lock);
> +
> + ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
> + AD4130_FIFO_CONTROL_WM_MASK,
> + FIELD_PREP(AD4130_FIFO_CONTROL_WM_MASK,
> + ad4130_watermark_reg_val(eff)));
> + if (ret)
> + goto out;
> +
> + st->effective_watermark = eff;
> + st->watermark = val;
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static const struct iio_info ad4130_info = {
> + .read_raw = ad4130_read_raw,
> + .read_avail = ad4130_read_avail,
> + .write_raw_get_fmt = ad4130_write_raw_get_fmt,
> + .write_raw = ad4130_write_raw,
> + .update_scan_mode = ad4130_update_scan_mode,
> + .hwfifo_set_watermark = ad4130_set_fifo_watermark,
> + .debugfs_reg_access = ad4130_reg_access,
> +};
> +
> +static int ad4130_buffer_postenable(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + mutex_lock(&st->lock);
> +
> + ret = ad4130_set_watermark_interrupt_en(st, true);
> + if (ret)
> + goto out;
> +
> + ret = irq_set_irq_type(st->spi->irq, st->inv_irq_trigger);
> + if (ret)
> + goto out;
> +
> + ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_WM);
> + if (ret)
> + goto out;
> +
> + ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static int ad4130_buffer_predisable(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int i;
> + int ret;
> +
> + mutex_lock(&st->lock);
> +
> + ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
> + if (ret)
> + goto out;
> +
> + ret = irq_set_irq_type(st->spi->irq, st->irq_trigger);
> + if (ret)
> + goto out;
> +
> + ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_DISABLED);
> + if (ret)
> + goto out;
> +
> + ret = ad4130_set_watermark_interrupt_en(st, false);
> + if (ret)
> + goto out;
> +
> + /*
> + * update_scan_mode() is not called in the disable path, disable all
> + * channels here.
> + */
> + for (i = 0; i < indio_dev->num_channels; i++) {
> + ret = ad4130_set_channel_enable(st, i, false);
> + if (ret)
> + goto out;
> + }
> +
> +out:
> + mutex_unlock(&st->lock);
> +
> + return ret;
> +}
> +
> +static const struct iio_buffer_setup_ops ad4130_buffer_ops = {
> + .postenable = ad4130_buffer_postenable,
> + .predisable = ad4130_buffer_predisable,
> +};
> +
> +static ssize_t hwfifo_watermark_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
> + unsigned int val;
> +
> + mutex_lock(&st->lock);
> + val = st->watermark;
> + mutex_unlock(&st->lock);
> +
> + return sysfs_emit(buf, "%d\n", val);
> +}
> +
> +static ssize_t hwfifo_enabled_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
> + unsigned int val;
> + int ret;
> +
> + ret = regmap_read(st->regmap, AD4130_FIFO_CONTROL_REG, &val);
> + if (ret)
> + return ret;
> +
> + val = FIELD_GET(AD4130_FIFO_CONTROL_MODE_MASK, val);
> +
> + return sysfs_emit(buf, "%d\n", val != AD4130_FIFO_MODE_DISABLED);
> +}
> +
> +static IIO_CONST_ATTR(hwfifo_watermark_min, "1");
> +static IIO_CONST_ATTR(hwfifo_watermark_max, __stringify(AD4130_FIFO_SIZE));
> +static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0);
> +static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0);
> +
> +static const struct attribute *ad4130_fifo_attributes[] = {
> + &iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
> + &iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
> + &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
> + &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
> + NULL
> +};
> +
> +static int _ad4130_find_table_index(const unsigned int *tbl, size_t len,
> + unsigned int val)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < len; i++)
> + if (tbl[i] == val)
> + return i;
> +
> + return -EINVAL;
> +}
> +
> +#define ad4130_find_table_index(table, val) \
> + _ad4130_find_table_index(table, ARRAY_SIZE(table), val)
> +
> +static int ad4130_get_ref_voltage(struct ad4130_state *st,
> + enum ad4130_ref_sel ref_sel)
> +{
> + switch (ref_sel) {
> + case AD4130_REF_REFIN1:
> + return regulator_get_voltage(st->regulators[2].consumer);
> + case AD4130_REF_REFIN2:
> + return regulator_get_voltage(st->regulators[3].consumer);
> + case AD4130_REF_AVDD_AVSS:
> + return regulator_get_voltage(st->regulators[0].consumer);
> + case AD4130_REF_REFOUT_AVSS:
> + return st->int_ref_uv;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int ad4130_parse_fw_setup(struct ad4130_state *st,
> + struct fwnode_handle *child,
> + struct ad4130_setup_info *setup_info)
> +{
> + struct device *dev = &st->spi->dev;
> + u32 tmp;
> + int ret;
> +
> + tmp = 0;
> + fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamp", &tmp);
> + ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
> + if (ret < 0)
> + return dev_err_probe(dev, ret,
> + "Invalid excitation current %unA\n", tmp);
> + setup_info->iout0_val = ret;
> +
> + tmp = 0;
> + fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamp", &tmp);
> + ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
> + if (ret < 0)
> + return dev_err_probe(dev, ret,
> + "Invalid excitation current %unA\n", tmp);
> + setup_info->iout1_val = ret;
> +
> + tmp = 0;
> + fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp);
> + ret = ad4130_find_table_index(ad4130_burnout_current_na_tbl, tmp);
> + if (ret < 0)
> + return dev_err_probe(dev, ret,
> + "Invalid burnout current %unA\n", tmp);
> + setup_info->burnout = ret;
> +
> + setup_info->ref_bufp = fwnode_property_read_bool(child, "adi,buffered-positive");
> + setup_info->ref_bufm = fwnode_property_read_bool(child, "adi,buffered-negative");
> +
> + setup_info->ref_sel = AD4130_REF_REFIN1;
> + fwnode_property_read_u32(child, "adi,reference-select",
> + &setup_info->ref_sel);
> + if (setup_info->ref_sel >= AD4130_REF_SEL_MAX)
> + return dev_err_probe(dev, -EINVAL,
> + "Invalid reference selected %u\n",
> + setup_info->ref_sel);
> +
> + if (setup_info->ref_sel == AD4130_REF_REFOUT_AVSS)
> + st->int_ref_en = true;
> +
> + ret = ad4130_get_ref_voltage(st, setup_info->ref_sel);
> + if (ret < 0)
> + return dev_err_probe(dev, ret, "Cannot use reference %u\n",
> + setup_info->ref_sel);
> +
> + return 0;
> +}
> +
> +static int ad4130_validate_diff_channel(struct ad4130_state *st, u32 pin)
> +{
> + struct device *dev = &st->spi->dev;
> +
> + if (pin >= AD4130_MAX_DIFF_INPUTS)
> + return dev_err_probe(dev, -EINVAL,
> + "Invalid diffreential channel %u\n", pin);
> +
> + if (pin >= AD4130_MAX_ANALOG_PINS)
> + return 0;
> +
> + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
> + return dev_err_probe(dev, -EINVAL,
> + "Pin %u already used with fn %u\n", pin,
> + st->pins_fn[pin]);
> +
> + st->pins_fn[pin] |= AD4130_PIN_FN_DIFF;
> +
> + return 0;
> +}
> +
> +static int ad4130_validate_diff_channels(struct ad4130_state *st,
> + u32 *pins, unsigned int len)
> +{
> + unsigned int i;
> + int ret;
> +
> + for (i = 0; i < len; i++) {
> + ret = ad4130_validate_diff_channel(st, pins[i]);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int ad4130_validate_excitation_pin(struct ad4130_state *st, u32 pin)
> +{
> + struct device *dev = &st->spi->dev;
> +
> + if (pin >= AD4130_MAX_ANALOG_PINS)
> + return dev_err_probe(dev, -EINVAL,
> + "Invalid excitation pin %u\n", pin);
> +
> + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
> + return dev_err_probe(dev, -EINVAL,
> + "Pin %u already used with fn %u\n", pin,
> + st->pins_fn[pin]);
> +
> + st->pins_fn[pin] |= AD4130_PIN_FN_EXCITATION;
> +
> + return 0;
> +}
> +
> +static int ad4130_validate_vbias_pin(struct ad4130_state *st, u32 pin)
> +{
> + struct device *dev = &st->spi->dev;
> +
> + if (pin >= AD4130_MAX_ANALOG_PINS)
> + return dev_err_probe(dev, -EINVAL, "Invalid vbias pin %u\n",
> + pin);
> +
> + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
> + return dev_err_probe(dev, -EINVAL,
> + "Pin %u already used with fn %u\n", pin,
> + st->pins_fn[pin]);
> +
> + st->pins_fn[pin] |= AD4130_PIN_FN_VBIAS;
> +
> + return 0;
> +}
> +
> +static int ad4130_validate_vbias_pins(struct ad4130_state *st,
> + u32 *pins, unsigned int len)
> +{
> + unsigned int i;
> + int ret;
> +
> + for (i = 0; i < st->num_vbias_pins; i++) {
> + ret = ad4130_validate_vbias_pin(st, pins[i]);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int ad4130_parse_fw_channel(struct iio_dev *indio_dev,
> + struct fwnode_handle *child)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + unsigned int resolution = ad4130_resolution(st);
> + unsigned int index = indio_dev->num_channels++;
> + struct device *dev = &st->spi->dev;
> + struct ad4130_chan_info *chan_info;
> + struct iio_chan_spec *chan;
> + u32 pins[2];
> + int ret;
> +
> + if (index >= AD4130_MAX_CHANNELS)
> + return dev_err_probe(dev, -EINVAL, "Too many channels\n");
> +
> + chan = &st->chans[index];
> + chan_info = &st->chans_info[index];
> +
> + *chan = ad4130_channel_template;
> + chan->scan_type.realbits = resolution;
> + chan->scan_type.storagebits = resolution;
> + chan->scan_index = index;
> +
> + chan_info->slot = AD4130_INVALID_SLOT;
> + chan_info->setup.fs = AD4130_FILTER_SELECT_MIN;
> + chan_info->initialized = true;
> +
> + ret = fwnode_property_read_u32_array(child, "diff-channels", pins,
> + ARRAY_SIZE(pins));
> + if (ret)
> + return ret;
> +
> + ret = ad4130_validate_diff_channels(st, pins, ARRAY_SIZE(pins));
> + if (ret)
> + return ret;
> +
> + chan->channel = pins[0];
> + chan->channel2 = pins[1];
> +
> + ret = ad4130_parse_fw_setup(st, child, &chan_info->setup);
> + if (ret)
> + return ret;
> +
> + fwnode_property_read_u32(child, "adi,excitation-pin-0",
> + &chan_info->iout0);
> + if (chan_info->setup.iout0_val != AD4130_IOUT_OFF) {
> + ret = ad4130_validate_excitation_pin(st, chan_info->iout0);
> + if (ret)
> + return ret;
> + }
> +
> + fwnode_property_read_u32(child, "adi,excitation-pin-1",
> + &chan_info->iout1);
> + if (chan_info->setup.iout1_val != AD4130_IOUT_OFF) {
> + ret = ad4130_validate_excitation_pin(st, chan_info->iout1);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int ad4130_parse_fw_children(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + struct device *dev = &st->spi->dev;
> + struct fwnode_handle *child;
> + int ret;
> +
> + indio_dev->channels = st->chans;
> +
> + device_for_each_child_node(dev, child) {
> + ret = ad4130_parse_fw_channel(indio_dev, child);
> + if (ret) {
> + fwnode_handle_put(child);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int ad4310_parse_fw(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + struct device *dev = &st->spi->dev;
> + u32 ext_clk_freq = AD4130_MCLK_FREQ_76_8KHZ;
> + bool int_clk_out;
> + unsigned int i;
> + int avdd_uv;
> + int irq;
> + int ret;
> +
> + st->mclk = devm_clk_get_optional(dev, "mclk");
> + if (IS_ERR(st->mclk))
> + return dev_err_probe(dev, PTR_ERR(st->mclk),
> + "Failed to get mclk\n");
> +
> + st->int_pin_sel = AD4130_INT_PIN_INT;
> +
> + for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) {
> + irq = fwnode_irq_get_byname(dev_fwnode(dev),
> + ad4130_int_pin_names[i]);
> + if (irq > 0) {
> + st->int_pin_sel = i;
> + break;
> + }
> + }
> +
> + if (st->int_pin_sel == AD4130_INT_PIN_DOUT)
> + return dev_err_probe(dev, -EINVAL,
> + "Cannot use DOUT as interrupt pin\n");
> +
> + if (st->int_pin_sel == AD4130_INT_PIN_P2)
> + st->pins_fn[AD4130_AIN3_P2] = AD4130_PIN_FN_SPECIAL;
> +
> + int_clk_out = device_property_read_bool(dev, "adi,int-clk-out");
> + if (st->mclk && int_clk_out)
> + return dev_err_probe(dev, -EINVAL,
> + "Cannot expose internal clock\n");
> +
> + device_property_read_u32(dev, "adi,ext-clk-freq-hz", &ext_clk_freq);
> + if (ext_clk_freq != AD4130_MCLK_FREQ_153_6KHZ &&
> + ext_clk_freq != AD4130_MCLK_FREQ_76_8KHZ)
> + return dev_err_probe(dev, -EINVAL,
> + "Invalid external clock frequency %u\n",
> + ext_clk_freq);
> +
> + if (st->mclk && ext_clk_freq == AD4130_MCLK_FREQ_153_6KHZ)
> + st->mclk_sel = AD4130_MCLK_153_6KHZ_EXT;
> + else if (st->mclk)
> + st->mclk_sel = AD4130_MCLK_76_8KHZ_EXT;
> + else if (int_clk_out)
> + st->mclk_sel = AD4130_MCLK_76_8KHZ_OUT;
> + else
> + st->mclk_sel = AD4130_MCLK_76_8KHZ;
> +
> + if (st->int_pin_sel == AD4130_INT_PIN_CLK &&
> + st->mclk_sel != AD4130_MCLK_76_8KHZ)
> + return dev_err_probe(dev, -EINVAL,
> + "Invalid clock %u for interrupt pin %u\n",
> + st->mclk_sel, st->int_pin_sel);
> +
> + st->int_ref_uv = AD4130_INT_REF_2_5V;
> +
> + /*
> + * When the AVDD supply is set to below 2.5V the internal reference of
> + * 1.25V should be selected.
> + * See datasheet page 37, section ADC REFERENCE.
> + */
> + avdd_uv = regulator_get_voltage(st->regulators[0].consumer);
> + if (avdd_uv > 0 && avdd_uv < AD4130_INT_REF_2_5V)
> + st->int_ref_uv = AD4130_INT_REF_1_25V;
> +
> + st->bipolar = device_property_read_bool(dev, "adi,bipolar");
> +
> + ret = device_property_count_u32(dev, "adi,vbias-pins");
> + if (ret > 0) {
> + if (ret > AD4130_MAX_ANALOG_PINS)
> + return dev_err_probe(dev, -EINVAL,
> + "Too many vbias pins %u\n", ret);
> +
> + st->num_vbias_pins = ret;
> +
> + ret = device_property_read_u32_array(dev, "adi,vbias-pins",
> + st->vbias_pins,
> + st->num_vbias_pins);
> + if (ret)
> + return dev_err_probe(dev, ret,
> + "Failed to read vbias pins\n");
> +
> + ret = ad4130_validate_vbias_pins(st, st->vbias_pins,
> + st->num_vbias_pins);
> + if (ret)
> + return ret;
> + }
> +
> + ret = ad4130_parse_fw_children(indio_dev);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static void ad4130_fill_scale_tbls(struct ad4130_state *st)
> +{
> + unsigned int pow = ad4130_resolution(st) - st->bipolar;
> + unsigned int i, j;
> +
> + for (i = 0; i < AD4130_REF_SEL_MAX; i++) {
> + int ret;
> + u64 nv;
> +
> + ret = ad4130_get_ref_voltage(st, i);
> + if (ret < 0)
> + continue;
> +
> + nv = (u64)ret * NANO;
> +
> + for (j = 0; j < AD4130_MAX_PGA; j++)
> + st->scale_tbls[i][j][1] = div_u64(nv >> (pow + j), MILLI);
> + }
> +}
> +
> +static void ad4130_clk_disable_unprepare(void *clk)
> +{
> + clk_disable_unprepare(clk);
> +}
> +
> +static int ad4130_setup(struct iio_dev *indio_dev)
> +{
> + struct ad4130_state *st = iio_priv(indio_dev);
> + struct device *dev = &st->spi->dev;
> + unsigned int int_ref_val;
> + unsigned long rate = AD4130_MCLK_FREQ_76_8KHZ;
> + unsigned int val;
> + unsigned int i;
> + int ret;
> +
> + if (st->mclk_sel == AD4130_MCLK_153_6KHZ_EXT)
> + rate = AD4130_MCLK_FREQ_153_6KHZ;
> +
> + ret = clk_set_rate(st->mclk, rate);
> + if (ret)
> + return ret;
> +
> + ret = clk_prepare_enable(st->mclk);
> + if (ret)
> + return ret;
> +
> + ret = devm_add_action_or_reset(dev, ad4130_clk_disable_unprepare,
> + st->mclk);
> + if (ret)
> + return ret;
> +
> + if (st->int_ref_uv == AD4130_INT_REF_2_5V)
> + int_ref_val = AD4130_INT_REF_VAL_2_5V;
> + else
> + int_ref_val = AD4130_INT_REF_VAL_1_25V;
> +
> + /* Switch to SPI 4-wire mode. */
> + val = FIELD_PREP(AD4130_ADC_CONTROL_CSB_EN_MASK, 1);
> + val |= FIELD_PREP(AD4130_ADC_CONTROL_BIPOLAR_MASK, st->bipolar);
> + val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_EN_MASK, st->int_ref_en);
> + val |= FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, AD4130_MODE_IDLE);
> + val |= FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, st->mclk_sel);
> + val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_VAL_MASK, int_ref_val);
> +
> + ret = regmap_write(st->regmap, AD4130_ADC_CONTROL_REG, val);
> + if (ret)
> + return ret;
> +
> + /*
> + * Configure all GPIOs for output. If configured, the interrupt function
> + * of P2 takes priority over the GPIO out function.
> + */
> + val = AD4130_IO_CONTROL_GPIO_CTRL_MASK;
> + val |= FIELD_PREP(AD4130_IO_CONTROL_INT_PIN_SEL_MASK, st->int_pin_sel);
> +
> + ret = regmap_write(st->regmap, AD4130_IO_CONTROL_REG, val);
> + if (ret)
> + return ret;
> +
> + val = 0;
> + for (i = 0; i < st->num_vbias_pins; i++)
> + val |= BIT(st->vbias_pins[i]);
> +
> + ret = regmap_write(st->regmap, AD4130_VBIAS_REG, val);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
> + AD4130_FIFO_CONTROL_HEADER_MASK, 0);
> + if (ret)
> + return ret;
> +
> + /* FIFO watermark interrupt starts out as enabled, disable it. */
> + ret = ad4130_set_watermark_interrupt_en(st, false);
> + if (ret)
> + return ret;
> +
> + /* Setup channels. */
> + for (i = 0; i < indio_dev->num_channels; i++) {
> + struct ad4130_chan_info *chan_info = &st->chans_info[i];
> + struct iio_chan_spec *chan = &st->chans[i];
> + unsigned int val;
> +
> + val = FIELD_PREP(AD4130_CHANNEL_AINP_MASK, chan->channel) |
> + FIELD_PREP(AD4130_CHANNEL_AINM_MASK, chan->channel2) |
> + FIELD_PREP(AD4130_CHANNEL_IOUT1_MASK, chan_info->iout0) |
> + FIELD_PREP(AD4130_CHANNEL_IOUT2_MASK, chan_info->iout1);
> +
> + ret = regmap_write(st->regmap, AD4130_CHANNEL_X_REG(i), val);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int ad4130_soft_reset(struct ad4130_state *st)
> +{
> + int ret;
> +
> + ret = spi_write(st->spi, st->reset_buf, sizeof(st->reset_buf));
> + if (ret)
> + return ret;
> +
> + fsleep(AD4130_RESET_SLEEP_US);
> +
> + return 0;
> +}
> +
> +static void ad4130_disable_regulators(void *data)
> +{
> + struct ad4130_state *st = data;
> +
> + regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators);
> +}
> +
> +static int ad4130_probe(struct spi_device *spi)
> +{
> + struct device *dev = &spi->dev;
> + struct iio_dev *indio_dev;
> + struct ad4130_state *st;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + st = iio_priv(indio_dev);
> +
> + memset(st->reset_buf, 0xff, sizeof(st->reset_buf));
> + init_completion(&st->completion);
> + mutex_init(&st->lock);
> + st->spi = spi;
> +
> + /*
> + * Xfer: [ XFR1 ] [ XFR2 ]
> + * Master: 0x7D N ......................
> + * Slave: ...... DATA1 DATA2 ... DATAN
> + */
> + st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_FIFO_DATA_REG;
> + st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
> + st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
> + st->fifo_xfer[1].rx_buf = st->fifo_rx_buf;
> + spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer,
> + ARRAY_SIZE(st->fifo_xfer));
> +
> + indio_dev->name = AD4130_NAME;
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->info = &ad4130_info;
> +
> + st->regmap = devm_regmap_init(dev, NULL, st, &ad4130_regmap_config);
> + if (IS_ERR(st->regmap))
> + return PTR_ERR(st->regmap);
> +
> + st->regulators[0].supply = "avdd";
> + st->regulators[1].supply = "iovdd";
> + st->regulators[2].supply = "refin1";
> + st->regulators[3].supply = "refin2";
> +
> + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators),
> + st->regulators);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to get regulators\n");
> +
> + ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to enable regulators\n");
> +
> + ret = devm_add_action_or_reset(dev, ad4130_disable_regulators, st);
> + if (ret)
> + return dev_err_probe(dev, ret,
> + "Failed to add regulators disable action\n");
> +
> + ret = ad4130_soft_reset(st);
> + if (ret)
> + return ret;
> +
> + ret = ad4310_parse_fw(indio_dev);
> + if (ret)
> + return ret;
> +
> + ret = ad4130_setup(indio_dev);
> + if (ret)
> + return ret;
> +
> + ad4130_fill_scale_tbls(st);
> +
> + st->gc.owner = THIS_MODULE;
> + st->gc.label = AD4130_NAME;
> + st->gc.base = -1;
> + st->gc.ngpio = AD4130_MAX_GPIOS;
> + st->gc.parent = dev;
> + st->gc.can_sleep = true;
> + st->gc.init_valid_mask = ad4130_gpio_init_valid_mask;
> + st->gc.get_direction = ad4130_gpio_get_direction;
> + st->gc.set = ad4130_gpio_set;
> +
> + ret = devm_gpiochip_add_data(dev, &st->gc, st);
> + if (ret)
> + return ret;
> +
> + ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev,
> + &ad4130_buffer_ops,
> + ad4130_fifo_attributes);
> + if (ret)
> + return ret;
> +
> + ret = devm_request_threaded_irq(dev, spi->irq, NULL,
> + ad4130_irq_handler, IRQF_ONESHOT,
> + indio_dev->name, indio_dev);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to request irq\n");
> +
> + /*
> + * When the chip enters FIFO mode, IRQ polarity is inverted.
> + * When the chip exits FIFO mode, IRQ polarity returns to normal.
> + * See datasheet pages: 65, FIFO Watermark Interrupt section,
> + * and 71, Bit Descriptions for STATUS Register, RDYB.
> + * Cache the normal and inverted IRQ triggers to set them when
> + * entering and exiting FIFO mode.
> + */
> + st->irq_trigger = irq_get_trigger_type(spi->irq);
> + if (st->irq_trigger & IRQF_TRIGGER_RISING)
> + st->inv_irq_trigger = IRQF_TRIGGER_FALLING;
> + else if (st->irq_trigger & IRQF_TRIGGER_FALLING)
> + st->inv_irq_trigger = IRQF_TRIGGER_RISING;
> + else
> + return dev_err_probe(dev, -EINVAL, "Invalid irq flags: %u\n",
> + st->irq_trigger);
> +
> + return devm_iio_device_register(dev, indio_dev);
> +}
> +
> +static const struct of_device_id ad4130_of_match[] = {
> + {
> + .compatible = "adi,ad4130",
> + },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, ad4130_of_match);
> +
> +static struct spi_driver ad4130_driver = {
> + .driver = {
> + .name = AD4130_NAME,
> + .of_match_table = ad4130_of_match,
> + },
> + .probe = ad4130_probe,
> +};
> +module_spi_driver(ad4130_driver);
> +
> +MODULE_AUTHOR("Cosmin Tanislav <[email protected]>");
> +MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver");
> +MODULE_LICENSE("GPL");
> --
> 2.36.1
>


--
With Best Regards,
Andy Shevchenko