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 <cosmin.tanislav@xxxxxxxxxx> --- MAINTAINERS | 8 + drivers/iio/adc/Kconfig | 13 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad4130.c | 2072 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 2094 insertions(+) create mode 100644 drivers/iio/adc/ad4130.c diff --git a/MAINTAINERS b/MAINTAINERS index a1dfb3fab5f8..8719a246b55d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1054,6 +1054,14 @@ 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 <cosmin.tanislav@xxxxxxxxxx> +L: linux-iio@xxxxxxxxxxxxxxx +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 <alexandru.tachici@xxxxxxxxxx> L: linux-iio@xxxxxxxxxxxxxxx diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 71ab0a06aa82..2dac0f029c41 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 39d806f6d457..c3aa7e4eca2f 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..89fb9b413ff0 --- /dev/null +++ b/drivers/iio/adc/ad4130.c @@ -0,0 +1,2072 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * AD4130 SPI ADC driver + * + * Copyright 2022 Analog Devices Inc. + */ +#include <asm/div64.h> +#include <asm/unaligned.h> +#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/iio/buffer.h> +#include <linux/iio/kfifo_buf.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define AD4130_8_NAME "ad4130-8" + +#define AD4130_COMMS_READ_MASK BIT(6) + +#define AD4130_REG_STATUS 0x00 +#define AD4130_STATUS_POR_FLAG_MASK BIT(4) + +#define AD4130_REG_ADC_CONTROL 0x01 +#define AD4130_BIPOLAR_MASK BIT(14) +#define AD4130_INT_REF_VAL_MASK BIT(13) +#define AD4130_INT_REF_2_5V 2500000 +#define AD4130_INT_REF_1_25V 1250000 +#define AD4130_CSB_EN_MASK BIT(9) +#define AD4130_INT_REF_EN_MASK BIT(8) +#define AD4130_MODE_MASK GENMASK(5, 2) +#define AD4130_MCLK_SEL_MASK GENMASK(1, 0) + +#define AD4130_REG_DATA 0x02 + +#define AD4130_REG_IO_CONTROL 0x03 +#define AD4130_INT_PIN_SEL_MASK GENMASK(9, 8) +#define AD4130_GPIO_DATA_MASK GENMASK(7, 4) +#define AD4130_GPIO_CTRL_MASK GENMASK(3, 0) + +#define AD4130_REG_VBIAS 0x04 + +#define AD4130_REG_ID 0x05 + +#define AD4130_REG_ERROR 0x06 + +#define AD4130_REG_ERROR_EN 0x07 + +#define AD4130_REG_CHANNEL_X(x) (0x09 + (x)) +#define AD4130_CHANNEL_EN_MASK BIT(23) +#define AD4130_SETUP_MASK GENMASK(22, 20) +#define AD4130_AINP_MASK GENMASK(17, 13) +#define AD4130_AINM_MASK GENMASK(12, 8) +#define AD4130_IOUT1_MASK GENMASK(7, 4) +#define AD4130_IOUT2_MASK GENMASK(3, 0) + +#define AD4130_REG_CONFIG_X(x) (0x19 + (x)) +#define AD4130_IOUT1_VAL_MASK GENMASK(15, 13) +#define AD4130_IOUT2_VAL_MASK GENMASK(12, 10) +#define AD4130_BURNOUT_MASK GENMASK(9, 8) +#define AD4130_REF_BUFP_MASK BIT(7) +#define AD4130_REF_BUFM_MASK BIT(6) +#define AD4130_REF_SEL_MASK GENMASK(5, 4) +#define AD4130_PGA_MASK GENMASK(3, 1) +#define AD4130_PGA_NUM 8 + +#define AD4130_REG_FILTER_X(x) (0x21 + (x)) +#define AD4130_FILTER_MODE_MASK GENMASK(15, 12) +#define AD4130_FILTER_SELECT_MASK GENMASK(10, 0) +#define AD4130_FS_MIN 1 +#define AD4130_MAX_ODR 2400 + +#define AD4130_REG_FIFO_CONTROL 0x3a +#define AD4130_ADD_FIFO_HEADER_MASK BIT(18) +#define AD4130_FIFO_MODE_MASK GENMASK(17, 16) +#define AD4130_WATERMARK_INT_EN_MASK BIT(9) +#define AD4130_WATERMARK_MASK GENMASK(7, 0) +#define AD4130_WATERMARK_256 0 + +#define AD4130_REG_FIFO_STATUS 0x3b + +#define AD4130_REG_FIFO_DATA 0x3d +#define AD4130_FIFO_SIZE 256 +#define AD4130_FIFO_MAX_SAMPLE_SIZE 3 + +#define AD4130_MAX_GPIOS 4 +#define AD4130_MAX_SETUPS 8 +#define AD4130_MAX_CHANNELS 16 +#define AD4130_MAX_ANALOG_PINS 16 +#define AD4130_MAX_DIFF_INPUTS 30 + +#define AD4130_AIN2_P1 0x2 + +#define AD4130_MCLK_FREQ_76_8KHZ 76800 +#define AD4130_MCLK_FREQ_153_6KHZ 153600 + +#define AD4130_RESET_CLK_COUNT 64 +#define AD4130_RESET_BUF_SIZE (AD4130_RESET_CLK_COUNT / 8) + +#define AD4130_SOFT_RESET_SLEEP (160 * 1000000 / AD4130_MCLK_FREQ_76_8KHZ) + +#define AD4130_INVALID_SLOT -1 + +#define AD4130_FREQ_FACTOR 1000000000ull +#define AD4130_DB3_FACTOR 1000 + +static const unsigned int ad4130_reg_size[] = { + [AD4130_REG_STATUS] = 1, + [AD4130_REG_ADC_CONTROL] = 2, + [AD4130_REG_IO_CONTROL] = 2, + [AD4130_REG_VBIAS] = 2, + [AD4130_REG_ID] = 1, + [AD4130_REG_ERROR] = 2, + [AD4130_REG_ERROR_EN] = 2, + [AD4130_REG_CHANNEL_X(0) ... + AD4130_REG_CHANNEL_X(AD4130_MAX_CHANNELS)] = 3, + [AD4130_REG_CONFIG_X(0) ... + AD4130_REG_CONFIG_X(AD4130_MAX_SETUPS)] = 2, + [AD4130_REG_FILTER_X(0) ... + AD4130_REG_FILTER_X(AD4130_MAX_SETUPS)] = 3, + [AD4130_REG_FIFO_CONTROL] = 3, + [AD4130_REG_FIFO_STATUS] = 1, +}; + +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_DOUT_OR_INT, + AD4130_INT_PIN_CLK, + AD4130_INT_PIN_P1, + 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_WATERMARK = 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, + AD4130_FILTER_MAX, +}; + +enum ad4130_pin_function { + AD4130_PIN_FN_NONE, + AD4130_PIN_FN_SPECIAL = 1 << 0, + AD4130_PIN_FN_DIFF = 1 << 1, + AD4130_PIN_FN_EXCITATION = 1 << 2, + AD4130_PIN_FN_VBIAS = 1 << 3, +}; + +struct ad4130_chip_info { + const char *name; + u8 resolution; + bool has_int_pin; +}; + +struct ad4130_setup_info { + unsigned int iout0_val; + unsigned int iout1_val; + unsigned int burnout; + unsigned int pga; + unsigned int fs; + bool ref_bufp; + bool ref_bufm; + u32 ref_sel; + enum ad4130_filter_mode filter_mode; + unsigned int enabled_channels; + unsigned int channels; +}; + +#define AD4130_SETUP_SIZE offsetof(struct ad4130_setup_info, \ + enabled_channels) + +struct ad4130_chan_info { + u32 iout0; + u32 iout1; + bool enabled; + struct ad4130_setup_info setup; + int slot; + bool initialized; +}; + +struct ad4130_filter_config { + enum ad4130_filter_mode filter_mode; + unsigned int odr_div; + unsigned int fs_max; + unsigned int db3_div; + enum iio_available_type samp_freq_avail_type; + int samp_freq_avail_len; + int samp_freq_avail[3][2]; + enum iio_available_type db3_freq_avail_type; + int db3_freq_avail_len; + int db3_freq_avail[3][2]; +}; + +struct ad4130_state { + const struct ad4130_chip_info *chip_info; + struct spi_device *spi; + struct regmap *regmap; + struct clk *mclk; + struct regulator_bulk_data regulators[4]; + u32 irq_trigger; + u32 inv_irq_trigger; + + /* + * Synchronize access to members 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_setup_info setups_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_PGA_NUM][2]; + struct gpio_chip gc; + unsigned int gpio_offsets[AD4130_MAX_GPIOS]; + unsigned int num_gpios; + + u32 int_pin_sel; + bool int_ref_en; + u32 int_ref_uv; + u32 mclk_sel; + 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 the + * transfer buffers to live in their own cache lines. + */ + u8 reset_buf[AD4130_RESET_BUF_SIZE] ____cacheline_aligned; + 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_DOUT_OR_INT] = "dout-int", + [AD4130_INT_PIN_CLK] = "clk", + [AD4130_INT_PIN_P1] = "p1", + [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, _db3_div) \ +{ \ + .filter_mode = (_filter_mode), \ + .odr_div = (_odr_div), \ + .fs_max = (_fs_max), \ + .db3_div = (_db3_div), \ + .samp_freq_avail_type = IIO_AVAIL_RANGE, \ + .samp_freq_avail_len = 3, \ + .samp_freq_avail = { \ + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \ + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \ + { AD4130_MAX_ODR, (_odr_div) }, \ + }, \ + .db3_freq_avail_type = IIO_AVAIL_RANGE, \ + .db3_freq_avail_len = 3, \ + .db3_freq_avail = { \ + { \ + AD4130_MAX_ODR * (_db3_div), \ + (_odr_div) * (_fs_max) * AD4130_DB3_FACTOR, \ + }, \ + { \ + AD4130_MAX_ODR * (_db3_div), \ + (_odr_div) * (_fs_max) * AD4130_DB3_FACTOR, \ + }, \ + { \ + AD4130_MAX_ODR * (_db3_div), \ + (_odr_div) * AD4130_DB3_FACTOR, \ + }, \ + }, \ +} + +#define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div, _db3_div) \ +{ \ + .filter_mode = (_filter_mode), \ + .odr_div = (_odr_div), \ + .fs_max = AD4130_FS_MIN, \ + .db3_div = (_db3_div), \ + .samp_freq_avail_type = IIO_AVAIL_LIST, \ + .samp_freq_avail_len = 1, \ + .samp_freq_avail = { \ + { AD4130_MAX_ODR, (_odr_div) }, \ + }, \ + .db3_freq_avail_type = IIO_AVAIL_LIST, \ + .db3_freq_avail_len = 1, \ + .db3_freq_avail = { \ + { \ + AD4130_MAX_ODR * AD4130_DB3_FACTOR, \ + (_odr_div) * (_db3_div) \ + }, \ + }, \ +} + +static const struct ad4130_filter_config ad4130_filter_configs[] = { + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4, 1, 10, 234), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10, 590), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3, 1, 2047, 268), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1, 2047, 268), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047, 545), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1, 92, 675), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2, 100, 675), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3, 124, 675), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4, 148, 675), +}; + +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 unsigned int ad4130_data_reg_size(struct ad4130_state *st) +{ + return st->chip_info->resolution / 8; +} + +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; + + if (reg == AD4130_REG_DATA) { + *size = ad4130_data_reg_size(st); + return 0; + } + + *size = ad4130_reg_size[reg]; + + if (!*size) + return -EINVAL; + + return 0; +} + +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: + ret = -EINVAL; + break; + } + + return 0; +} + +static const struct regmap_config ad4130_regmap_config = { + .reg_read = ad4130_reg_read, + .reg_write = ad4130_reg_write, +}; + +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 real_offset = st->gpio_offsets[offset]; + unsigned int mask = FIELD_PREP(AD4130_GPIO_DATA_MASK, BIT(real_offset)); + + regmap_update_bits(st->regmap, AD4130_REG_IO_CONTROL, mask, + value ? mask : 0); +} + +static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode) +{ + return regmap_update_bits(st->regmap, AD4130_REG_ADC_CONTROL, + AD4130_MODE_MASK, + FIELD_PREP(AD4130_MODE_MASK, mode)); +} + +static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en) +{ + return regmap_update_bits(st->regmap, AD4130_REG_FIFO_CONTROL, + AD4130_WATERMARK_INT_EN_MASK, + en ? AD4130_WATERMARK_INT_EN_MASK : 0); +} + +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_REG_FIFO_CONTROL, + AD4130_FIFO_MODE_MASK, + FIELD_PREP(AD4130_FIFO_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_setup_info *setup_info = &st->setups_info[i]; + + /* Immediately accept a matching setup info. */ + if (!memcmp(target_setup_info, setup_info, AD4130_SETUP_SIZE)) { + *slot = i; + return 0; + } + + /* Ignore all setups which are used by enabled channels. */ + if (setup_info->enabled_channels) + continue; + + /* Find the least used slot. */ + if (*slot == AD4130_INVALID_SLOT || + setup_info->channels < st->setups_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_setup_info *setup_info = &st->setups_info[chan_info->slot]; + + chan_info->slot = AD4130_INVALID_SLOT; + setup_info->channels--; +} + +static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot) +{ + struct ad4130_setup_info *setup_info = &st->setups_info[slot]; + unsigned int i; + + if (setup_info->enabled_channels) + return -EINVAL; + + 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_setup_info *setup_info = &st->setups_info[slot]; + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + int ret; + + ret = regmap_update_bits(st->regmap, AD4130_REG_CHANNEL_X(channel), + AD4130_SETUP_MASK, + FIELD_PREP(AD4130_SETUP_MASK, slot)); + if (ret) + return ret; + + chan_info->slot = slot; + setup_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_IOUT1_VAL_MASK, setup_info->iout0_val) | + FIELD_PREP(AD4130_IOUT1_VAL_MASK, setup_info->iout1_val) | + FIELD_PREP(AD4130_BURNOUT_MASK, setup_info->burnout) | + FIELD_PREP(AD4130_REF_BUFP_MASK, setup_info->ref_bufp) | + FIELD_PREP(AD4130_REF_BUFM_MASK, setup_info->ref_bufm) | + FIELD_PREP(AD4130_REF_SEL_MASK, setup_info->ref_sel) | + FIELD_PREP(AD4130_PGA_MASK, setup_info->pga); + + ret = regmap_write(st->regmap, AD4130_REG_CONFIG_X(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_REG_FILTER_X(slot), val); + if (ret) + return ret; + + memcpy(&st->setups_info[slot], setup_info, AD4130_SETUP_SIZE); + + 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 slot. If not possible, return error. + * - Unlink channel from current slot. + * - If 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 slot. If not possible, return error. + * - If slot has channels linked to it, unlink all channels, and + * write the new setup to it. + * - Link channel to 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); + + /* Case 3 & 5 */ + return 0; + } + + /* Case 1 & 2 */ + ret = ad4130_find_slot(st, setup_info, &slot, &overwrite); + if (ret) + return ret; + + if (chan_info->slot != AD4130_INVALID_SLOT) + /* Case 1 only */ + 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_setup_info *setup_info; + int ret; + + if (chan_info->enabled == status) + return 0; + + if (status) { + ret = ad4130_write_channel_setup(st, channel, true); + if (ret) + return ret; + } + + setup_info = &st->setups_info[chan_info->slot]; + + ret = regmap_update_bits(st->regmap, AD4130_REG_CHANNEL_X(channel), + AD4130_CHANNEL_EN_MASK, + status ? AD4130_CHANNEL_EN_MASK : 0); + if (ret) + return ret; + + setup_info->enabled_channels += status ? 1 : -1; + chan_info->enabled = status; + + return 0; +} + +static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode, + int val, int val2, unsigned int *fs, bool db3) +{ + const struct ad4130_filter_config *filter_config = + &ad4130_filter_configs[filter_mode]; + unsigned long long dividend, divisor; + int temp; + + dividend = filter_config->fs_max * filter_config->odr_div * + (val * AD4130_FREQ_FACTOR + val2); + divisor = AD4130_MAX_ODR * AD4130_FREQ_FACTOR; + + if (db3) { + dividend *= AD4130_DB3_FACTOR; + divisor *= filter_config->db3_div; + } + + temp = AD4130_FS_MIN + filter_config->fs_max - + DIV64_U64_ROUND_CLOSEST(dividend, divisor); + + if (temp < AD4130_FS_MIN) + temp = AD4130_FS_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, bool db3) +{ + 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_FS_MIN) * + AD4130_MAX_ODR; + divisor = filter_config->fs_max * filter_config->odr_div; + + if (db3) { + dividend *= filter_config->db3_div; + divisor *= AD4130_DB3_FACTOR; + } + + temp = div_u64(dividend * AD4130_FREQ_FACTOR, divisor); + *val = div_u64_rem(temp, AD4130_FREQ_FACTOR, 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; + + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs, + &freq_val, &freq_val2, false); + + ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs, false); + + 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) | + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_SAMP_FREQ) | + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), + .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_PGA_NUM; 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_PGA_NUM) + 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, bool db3) +{ + 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, db3); + + 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_REG_DATA, 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 ? -(1 << (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, false); + mutex_unlock(&st->lock); + + return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + mutex_lock(&st->lock); + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs, + val, val2, true); + 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; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + mutex_lock(&st->lock); + filter_config = &ad4130_filter_configs[setup_info->filter_mode]; + mutex_unlock(&st->lock); + + *vals = (int *)filter_config->db3_freq_avail; + *length = filter_config->db3_freq_avail_len * 2; + *type = IIO_VAL_FRACTIONAL; + + return filter_config->db3_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: + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + 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, false); + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + return ad4130_set_channel_freq(st, channel, val, val2, true); + 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 val = 0; + unsigned int i; + int ret; + + mutex_lock(&st->lock); + + for (i = 0; i < indio_dev->num_channels; i++) { + bool status = test_bit(i, scan_mask); + + if (!status) + continue; + + ret = ad4130_set_channel_enable(st, i, status); + 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 = 0; + + if (val > AD4130_FIFO_SIZE) + return -EINVAL; + + /* + * Always set watermark to a multiple of the number of enabled channels + * to avoid making the FIFO unaligned. + */ + eff = rounddown(val, st->num_enabled_channels); + + mutex_lock(&st->lock); + + ret = regmap_update_bits(st->regmap, AD4130_REG_FIFO_CONTROL, + AD4130_WATERMARK_MASK, + FIELD_PREP(AD4130_WATERMARK_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; + + /* When the chip enters FIFO mode, IRQ polarity is inversed. */ + 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_WATERMARK); + 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; + + /* When the chip exits FIFO mode, IRQ polarity returns to normal. */ + 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; + + 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 ad4130_get_fifo_watermark(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 ad4130_get_fifo_enabled(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_REG_FIFO_CONTROL, &val); + if (ret) + return ret; + + val = FIELD_GET(AD4130_FIFO_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(hwfifo_watermark, 0444, + ad4130_get_fifo_watermark, NULL, 0); +static IIO_DEVICE_ATTR(hwfifo_enabled, 0444, + ad4130_get_fifo_enabled, NULL, 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 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; +} + +static int ad4130_get_ref_voltage(struct ad4130_state *st, + enum ad4130_ref_sel ref_sel, + unsigned int *ref_uv) +{ + struct device *dev = &st->spi->dev; + int ret; + + switch (ref_sel) { + case AD4130_REF_REFIN1: + ret = regulator_get_voltage(st->regulators[2].consumer); + break; + case AD4130_REF_REFIN2: + ret = regulator_get_voltage(st->regulators[3].consumer); + break; + case AD4130_REF_AVDD_AVSS: + ret = regulator_get_voltage(st->regulators[0].consumer); + break; + case AD4130_REF_REFOUT_AVSS: + if (!st->int_ref_en) { + ret = -EINVAL; + break; + } + + ret = st->int_ref_uv; + break; + default: + ret = -EINVAL; + break; + } + + if (ret <= 0) + return dev_err_probe(dev, ret, "Cannot use reference %u\n", + ref_sel); + + if (ref_uv) + *ref_uv = ret; + + return 0; +} + +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 current_na; + int ret; + + current_na = 0; + fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamps", + ¤t_na); + ret = find_table_index(ad4130_iout_current_na_tbl, AD4130_IOUT_MAX, + current_na); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid excitation current %unA\n", + current_na); + setup_info->iout0_val = ret; + + current_na = 0; + fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamps", + ¤t_na); + ret = find_table_index(ad4130_iout_current_na_tbl, AD4130_IOUT_MAX, + current_na); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid excitation current %unA\n", + current_na); + setup_info->iout1_val = ret; + + current_na = 0; + fwnode_property_read_u32(child, "adi,burnout-current-nanoamps", + ¤t_na); + ret = find_table_index(ad4130_burnout_current_na_tbl, + AD4130_BURNOUT_MAX, current_na); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid burnout current %unA\n", + current_na); + 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_REFOUT_AVSS; + 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); + + ret = ad4130_get_ref_voltage(st, setup_info->ref_sel, NULL); + if (ret) + return ret; + + 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 = 0; + + for (i = 0; i < len; i++) { + ret = ad4130_validate_diff_channel(st, pins[i]); + if (ret) + break; + } + + return ret; +} + +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 = 0; + + for (i = 0; i < st->num_vbias_pins; i++) { + ret = ad4130_validate_vbias_pin(st, pins[i]); + if (ret) + break; + } + + return ret; +} + +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 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 = st->chip_info->resolution; + chan->scan_type.storagebits = st->chip_info->resolution; + chan->scan_index = index; + + chan_info->slot = AD4130_INVALID_SLOT; + chan_info->setup.fs = AD4130_FS_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]; + + fwnode_property_read_u32(child, "adi,excitation-pin-0", + &chan_info->iout0); + 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); + ret = ad4130_validate_excitation_pin(st, chan_info->iout1); + if (ret) + return ret; + + return ad4130_parse_fw_setup(st, child, &chan_info->setup); +} + +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) + break; + } + + fwnode_handle_put(child); + + return ret; +} + +static int ad4310_parse_fw(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + struct device *dev = &st->spi->dev; + 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_DOUT_OR_INT; + + for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) { + irq = of_irq_get_byname(dev->of_node, ad4130_int_pin_names[i]); + if (irq > 0) { + st->int_pin_sel = i; + break; + } + } + + if (st->int_pin_sel == AD4130_INT_PIN_DOUT || + (st->int_pin_sel == AD4130_INT_PIN_DOUT_OR_INT && + !st->chip_info->has_int_pin)) + return dev_err_probe(dev, -EINVAL, + "Cannot use DOUT as interrupt pin\n"); + + if (st->int_pin_sel == AD4130_INT_PIN_P1) + st->pins_fn[AD4130_AIN2_P1] = AD4130_PIN_FN_SPECIAL; + + st->mclk_sel = AD4130_MCLK_76_8KHZ; + device_property_read_u32(dev, "adi,mclk-sel", &st->mclk_sel); + + if (st->mclk_sel >= AD4130_MCLK_SEL_MAX) + return dev_err_probe(dev, -EINVAL, "Invalid clock %u\n", + st->mclk_sel); + + if (st->mclk && (st->mclk_sel == AD4130_MCLK_76_8KHZ || + st->mclk_sel == AD4130_MCLK_76_8KHZ_OUT)) + return dev_err_probe(dev, -EINVAL, + "Cannot use external clock\n"); + + 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_en = true; + if (device_property_present(dev, "adi,int-ref-en")) + st->int_ref_en = device_property_read_bool(dev, "adi,int-ref-en"); + + 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. + */ + 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) { + 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; + + for (i = 0; i < AD4130_MAX_GPIOS; i++) { + if (st->pins_fn[i + AD4130_AIN2_P1] != AD4130_PIN_FN_NONE) + continue; + + st->gpio_offsets[st->num_gpios++] = i; + } + + return 0; +} + +static void ad4130_fill_scale_tbls(struct ad4130_state *st) +{ + unsigned int i, j; + + for (i = 0; i < AD4130_REF_SEL_MAX; i++) { + unsigned int ref_uv; + int ret; + + ret = ad4130_get_ref_voltage(st, i, &ref_uv); + if (ret) + continue; + + for (j = 0; j < AD4130_PGA_NUM; j++) { + unsigned int pow = st->chip_info->resolution + j - + st->bipolar; + unsigned int nv = div_u64(((ref_uv * 1000000000ull) >> + pow), 1000); + + st->scale_tbls[i][j][0] = 0; + st->scale_tbls[i][j][1] = nv; + } + } +} + +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 = AD4130_CSB_EN_MASK; + val |= st->bipolar ? AD4130_BIPOLAR_MASK : 0; + val |= st->int_ref_en ? AD4130_INT_REF_EN_MASK : 0; + val |= FIELD_PREP(AD4130_MODE_MASK, AD4130_MODE_IDLE); + val |= FIELD_PREP(AD4130_MCLK_SEL_MASK, st->mclk_sel); + val |= FIELD_PREP(AD4130_INT_REF_VAL_MASK, int_ref_val); + + ret = regmap_write(st->regmap, AD4130_REG_ADC_CONTROL, val); + if (ret) + return ret; + + val = FIELD_PREP(AD4130_INT_PIN_SEL_MASK, st->int_pin_sel); + for (i = 0; i < st->num_gpios; i++) + val |= BIT(st->gpio_offsets[i]); + + ret = regmap_write(st->regmap, AD4130_REG_IO_CONTROL, 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_REG_VBIAS, val); + if (ret) + return ret; + + ret = regmap_update_bits(st->regmap, AD4130_REG_FIFO_CONTROL, + AD4130_ADD_FIFO_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_AINP_MASK, chan->channel) | + FIELD_PREP(AD4130_AINM_MASK, chan->channel2) | + FIELD_PREP(AD4130_IOUT1_MASK, chan_info->iout0) | + FIELD_PREP(AD4130_IOUT2_MASK, chan_info->iout1); + + ret = regmap_write(st->regmap, AD4130_REG_CHANNEL_X(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_SOFT_RESET_SLEEP); + + 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) +{ + const struct ad4130_chip_info *info; + struct device *dev = &spi->dev; + struct iio_dev *indio_dev; + struct ad4130_state *st; + int ret; + + info = device_get_match_data(dev); + if (!info) + return -ENODEV; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + memset(st->reset_buf, 0xff, AD4130_RESET_BUF_SIZE); + init_completion(&st->completion); + mutex_init(&st->lock); + st->chip_info = info; + st->spi = spi; + + /* + * Xfer: [ XFR1 ] [ XFR2 ] + * Master: 0x7D N ...................... + * Slave: ...... DATA1 DATA2 ... DATAN + */ + st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_REG_FIFO_DATA; + 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 = st->chip_info->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); + + if (st->num_gpios) { + st->gc.owner = THIS_MODULE; + st->gc.label = st->chip_info->name; + st->gc.base = -1; + st->gc.ngpio = AD4130_MAX_GPIOS; + st->gc.parent = dev; + st->gc.can_sleep = true; + 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, + INDIO_BUFFER_SOFTWARE, + &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"); + + 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 ad4130_chip_info ad4130_chip_info_tbl[] = { + [ID_AD4130_8_24_WLCSP] = { + .name = AD4130_8_NAME, + .resolution = 24, + .has_int_pin = true, + }, + [ID_AD4130_8_24_LFCSP] = { + .name = AD4130_8_NAME, + .resolution = 24, + .has_int_pin = false, + }, + [ID_AD4130_8_16_WLCSP] = { + .name = AD4130_8_NAME, + .resolution = 16, + .has_int_pin = true, + }, + [ID_AD4130_8_16_LFCSP] = { + .name = AD4130_8_NAME, + .resolution = 16, + .has_int_pin = false, + }, +}; + +static const struct of_device_id ad4130_of_match[] = { + { + .compatible = "adi,ad4130-8-16-lfcsp", + .data = &ad4130_chip_info_tbl[ID_AD4130_8_16_LFCSP], + }, + { + .compatible = "adi,ad4130-8-16-wlcsp", + .data = &ad4130_chip_info_tbl[ID_AD4130_8_16_WLCSP], + }, + { + .compatible = "adi,ad4130-8-24-lfcsp", + .data = &ad4130_chip_info_tbl[ID_AD4130_8_24_LFCSP], + }, + { + .compatible = "adi,ad4130-8-24-wlcsp", + .data = &ad4130_chip_info_tbl[ID_AD4130_8_24_WLCSP], + }, + { }, +}; +MODULE_DEVICE_TABLE(of, ad4130_of_match); + +static struct spi_driver ad4130_driver = { + .driver = { + .name = "ad4130", + .of_match_table = ad4130_of_match, + }, + .probe = ad4130_probe, +}; +module_spi_driver(ad4130_driver); + +MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver"); +MODULE_LICENSE("GPL"); -- 2.35.1
