This adds a new driver for the Analog Devices INC. AD4030-24 ADC. The driver implements basic support for the AD4030-24 1 channel differential ADC with hardware gain and offset control. Signed-off-by: Esteban Blanc <eblanc@xxxxxxxxxxxx> --- MAINTAINERS | 1 + drivers/iio/adc/Kconfig | 13 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad4030.c | 854 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 869 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index f17c42bea19c..6a5a0e7b7a51 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -420,6 +420,7 @@ R: Esteban Blanc <eblanc@xxxxxxxxxxxx> S: Supported W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/iio/adc/adi,ad4030.yaml +F: drivers/iio/adc/ad4030.c AD5110 ANALOG DEVICES DIGITAL POTENTIOMETERS DRIVER M: Mugilraj Dhavachelvan <dmugil2000@xxxxxxxxx> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 88e8ce2e78b3..f4bd05780f6f 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -33,6 +33,19 @@ config AD4000 To compile this driver as a module, choose M here: the module will be called ad4000. +config AD4030 + tristate "Analog Device AD4630 ADC Driver" + depends on SPI + depends on GPIOLIB + select REGMAP_SPI + select IIO_BUFFER + help + Say yes here to build support for Analog Devices AD4030 and AD4630 high speed + SPI analog to digital converters (ADC). + + To compile this driver as a module, choose M here: the module will be + called ad4030. + config AD4130 tristate "Analog Device AD4130 ADC Driver" depends on SPI diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 8b80664c6d6b..0e4f833abf0b 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_AB8500_GPADC) += ab8500-gpadc.o obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o obj-$(CONFIG_AD4000) += ad4000.o +obj-$(CONFIG_AD4030) += ad4030.o obj-$(CONFIG_AD4130) += ad4130.o obj-$(CONFIG_AD4695) += ad4695.o obj-$(CONFIG_AD7091R) += ad7091r-base.o diff --git a/drivers/iio/adc/ad4030.c b/drivers/iio/adc/ad4030.c new file mode 100644 index 000000000000..a981dce988e5 --- /dev/null +++ b/drivers/iio/adc/ad4030.c @@ -0,0 +1,854 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD4030 and AD4630 ADC family driver. + * + * Copyright 2024 Analog Devices, Inc. + * Copyright 2024 BayLibre, SAS + * + * based on code from: + * Analog Devices, Inc. + * Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx> + * Nuno Sa <nuno.sa@xxxxxxxxxx> + * Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> + * Liviu Adace <liviu.adace@xxxxxxxxxx> + */ + +#include <linux/bitfield.h> +#include <linux/units.h> +#include <linux/clk.h> +#include <linux/spi/spi.h> +#include <linux/regmap.h> +#include <linux/iio/iio.h> +#include <linux/regulator/consumer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define AD4030_REG_INTERFACE_CONFIG_A 0x00 +#define AD4030_REG_INTERFACE_CONFIG_A_SW_RESET (BIT(0) | BIT(7)) +#define AD4030_REG_INTERFACE_CONFIG_B 0x01 +#define AD4030_REG_DEVICE_CONFIG 0x02 +#define AD4030_REG_CHIP_TYPE 0x03 +#define AD4030_REG_PRODUCT_ID_L 0x04 +#define AD4030_REG_PRODUCT_ID_H 0x05 +#define AD4030_REG_CHIP_GRADE 0x06 +#define AD4030_REG_CHIP_GRADE_AD4030_24_GRADE 0x10 +#define AD4030_REG_CHIP_GRADE_MASK_CHIP_GRADE GENMASK(7, 3) +#define AD4030_REG_SCRATCH_PAD 0x0A +#define AD4030_REG_SPI_REVISION 0x0B +#define AD4030_REG_VENDOR_L 0x0C +#define AD4030_REG_VENDOR_H 0x0D +#define AD4030_REG_STREAM_MODE 0x0E +#define AD4030_REG_INTERFACE_CONFIG_C 0x10 +#define AD4030_REG_INTERFACE_STATUS_A 0x11 +#define AD4030_REG_EXIT_CFG_MODE 0x14 +#define AD4030_REG_EXIT_CFG_MODE_EXIT_MSK BIT(0) +#define AD4030_REG_AVG 0x15 +#define AD4030_REG_AVG_MASK_AVG_SYNC BIT(7) +#define AD4030_REG_AVG_MASK_AVG_VAL GENMASK(4, 0) +#define AD4030_REG_OFFSET_X0_0 0x16 +#define AD4030_REG_OFFSET_X0_1 0x17 +#define AD4030_REG_OFFSET_X0_2 0x18 +#define AD4030_REG_OFFSET_X1_0 0x19 +#define AD4030_REG_OFFSET_X1_1 0x1A +#define AD4030_REG_OFFSET_X1_2 0x1B +#define AD4030_REG_OFFSET_BYTES_NB 3 +#define AD4030_REG_OFFSET_CHAN(ch) (AD4030_REG_OFFSET_X0_2 + \ + (AD4030_REG_OFFSET_BYTES_NB * \ + (ch))) +#define AD4030_REG_GAIN_X0_LSB 0x1C +#define AD4030_REG_GAIN_X0_MSB 0x1D +#define AD4030_REG_GAIN_X1_LSB 0x1E +#define AD4030_REG_GAIN_X1_MSB 0x1F +#define AD4030_REG_GAIN_MAX_GAIN 1999970 +#define AD4030_REG_GAIN_BYTES_NB 2 +#define AD4030_REG_GAIN_CHAN(ch) (AD4030_REG_GAIN_X0_MSB + \ + (AD4030_REG_GAIN_BYTES_NB * \ + (ch))) +#define AD4030_REG_MODES 0x20 +#define AD4030_REG_MODES_MASK_OUT_DATA_MODE GENMASK(2, 0) +#define AD4030_REG_MODES_MASK_LANE_MODE GENMASK(7, 6) +#define AD4030_REG_OSCILATOR 0x21 +#define AD4030_REG_IO 0x22 +#define AD4030_REG_IO_MASK_IO2X BIT(1) +#define AD4030_REG_PAT0 0x23 +#define AD4030_REG_PAT1 0x24 +#define AD4030_REG_PAT2 0x25 +#define AD4030_REG_PAT3 0x26 +#define AD4030_REG_DIG_DIAG 0x34 +#define AD4030_REG_DIG_ERR 0x35 + +/* Sequence starting with "1 0 1" to enable reg access */ +#define AD4030_REG_ACCESS 0xa0 + +#define AD4030_MAX_IIO_SAMPLE_SIZE_BUFFERED BITS_TO_BYTES(64) +#define AD4030_MAX_HARDWARE_CHANNEL_NB 2 +#define AD4030_MAX_IIO_CHANNEL_NB 5 +#define AD4030_COMMON_BYTE_CHANNELS_FILTER 0xA +/* + * This accounts for for 1 sample per channel plus one u64 for the timestamp, + * aligned on a u64 boundary + */ +#define AD4030_MAXIMUM_RX_BUFFER_SIZE \ + ALIGN(AD4030_MAX_IIO_SAMPLE_SIZE_BUFFERED * \ + AD4030_MAX_HARDWARE_CHANNEL_NB, \ + sizeof(u64)) + sizeof(u64) + +#define AD4030_VREF_MIN_UV (4096 * MILLI) +#define AD4030_VREF_MAX_UV (5000 * MILLI) +#define AD4030_VIO_THRESHOLD_UV (1400 * MILLI) + +#define AD4030_SPI_MAX_XFER_LEN 8 +#define AD4030_SPI_MAX_REG_XFER_SPEED (80 * MEGA) +#define AD4030_TCNVH_NS 10 +#define AD4030_TCNVL_NS 20 +#define AD4030_TCYC_NS 500 +#define AD4030_TCYC_ADJUSTED_NS (AD4030_TCYC_NS - AD4030_TCNVL_NS) +#define AD4030_TRESET_PW_NS 50 +#define AD4030_TRESET_COM_DELAY_MS 750 + +enum ad4030_out_mode { + AD4030_OUT_DATA_MD_16_DIFF = 0x00, + AD4030_OUT_DATA_MD_24_DIFF = 0x00, + AD4030_OUT_DATA_MD_16_DIFF_8_COM = 0x01, + AD4030_OUT_DATA_MD_24_DIFF_8_COM = 0x02, + AD4030_OUT_DATA_MD_30_AVERAGED_DIFF = 0x03, + AD4030_OUT_DATA_MD_32_PATTERN = 0x04 +}; + +struct ad4030_chip_info { + const char *name; + const unsigned long *available_masks; + unsigned int available_masks_len; + const struct iio_chan_spec channels[AD4030_MAX_IIO_CHANNEL_NB]; + u8 grade; + u8 precision_bits; + /* Number of hardware channels */ + int num_channels; + unsigned int tcyc; +}; + +struct ad4030_state { + struct spi_device *spi; + struct regmap *regmap; + const struct ad4030_chip_info *chip; + struct gpio_desc *cnv_gpio; + int vref_uv; + int vio_uv; + int offset_avail[3]; + u32 conversion_speed_hz; + enum ad4030_out_mode mode; + + /* + * DMA (thus cache coherency maintenance) requires the transfer buffers + * to live in their own cache lines. + */ + u8 tx_data[AD4030_SPI_MAX_XFER_LEN] __aligned(IIO_DMA_MINALIGN); + struct { + union { + u8 raw[AD4030_MAXIMUM_RX_BUFFER_SIZE]; + struct { + s32 val; + u32 common; + } __packed buffered[AD4030_MAX_HARDWARE_CHANNEL_NB]; + }; + } rx_data __aligned(IIO_DMA_MINALIGN); +}; + +#define AD4030_CHAN_CMO(_idx) { \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = _idx * 2 + 2, \ + .scan_index = _idx * 2 + 1, \ + .extend_name = "Channel" #_idx " common byte part", \ + .scan_type = { \ + .sign = 'u', \ + .storagebits = 32, \ + .realbits = 8, \ + .endianness = IIO_BE, \ + }, \ +} + +#define AD4030_CHAN_IN(_idx, _storage, _real, _shift) { \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBSCALE) | \ + BIT(IIO_CHAN_INFO_CALIBBIAS) | \ + BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_separate_available = BIT(IIO_CHAN_INFO_CALIBBIAS) | \ + BIT(IIO_CHAN_INFO_CALIBSCALE), \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = _idx * 2, \ + .channel2 = _idx * 2 + 1, \ + .scan_index = _idx * 2, \ + .extend_name = "Channel" #_idx " differential part", \ + .differential = true, \ + .scan_type = { \ + .sign = 's', \ + .storagebits = _storage, \ + .realbits = _real, \ + .shift = _shift, \ + .endianness = IIO_BE, \ + }, \ +} + +static int ad4030_spi_read(void *context, const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct ad4030_state *st = context; + + struct spi_transfer xfer = { + .tx_buf = st->tx_data, + .rx_buf = st->rx_data.raw, + .len = reg_size + val_size, + }; + int ret; + + memcpy(st->tx_data, reg, reg_size); + + /* + * This should use spi_write_the_read but when doing so, CS never get + * deasserted. + */ + ret = spi_sync_transfer(st->spi, &xfer, 1); + if (ret) + return ret; + + memcpy(val, &st->rx_data.raw[reg_size], val_size); + + return ret; +} + +static int ad4030_spi_write(void *context, const void *data, size_t count) +{ + const struct ad4030_state *st = context; + + return spi_write(st->spi, data, count); +} + +static const struct regmap_bus ad4030_regmap_bus = { + .read = ad4030_spi_read, + .write = ad4030_spi_write, + .reg_format_endian_default = REGMAP_ENDIAN_BIG, +}; + +static const struct regmap_range ad4030_regmap_rd_range[] = { + regmap_reg_range(AD4030_REG_INTERFACE_CONFIG_A, AD4030_REG_CHIP_GRADE), + regmap_reg_range(AD4030_REG_SCRATCH_PAD, AD4030_REG_STREAM_MODE), + regmap_reg_range(AD4030_REG_INTERFACE_CONFIG_C, AD4030_REG_INTERFACE_STATUS_A), + regmap_reg_range(AD4030_REG_EXIT_CFG_MODE, AD4030_REG_PAT3), + regmap_reg_range(AD4030_REG_DIG_DIAG, AD4030_REG_DIG_ERR), +}; + +static const struct regmap_range ad4030_regmap_wr_range[] = { + regmap_reg_range(AD4030_REG_CHIP_TYPE, AD4030_REG_CHIP_GRADE), + regmap_reg_range(AD4030_REG_SPI_REVISION, AD4030_REG_VENDOR_H), +}; + +static const struct regmap_access_table ad4030_regmap_rd_table = { + .yes_ranges = ad4030_regmap_rd_range, + .n_yes_ranges = ARRAY_SIZE(ad4030_regmap_rd_range), +}; + +static const struct regmap_access_table ad4030_regmap_wr_table = { + .no_ranges = ad4030_regmap_wr_range, + .n_no_ranges = ARRAY_SIZE(ad4030_regmap_wr_range), +}; + +static const struct regmap_config ad4030_regmap_config = { + .reg_bits = 16, + .val_bits = 8, + .read_flag_mask = 0x80, + .rd_table = &ad4030_regmap_rd_table, + .wr_table = &ad4030_regmap_wr_table, + .max_register = AD4030_REG_DIG_ERR, +}; + +static int ad4030_enter_config_mode(struct ad4030_state *st) +{ + st->rx_data.raw[0] = AD4030_REG_ACCESS; + + return spi_write(st->spi, st->rx_data.raw, 1); +} + +static int ad4030_exit_config_mode(struct ad4030_state *st) +{ + return regmap_write(st->regmap, AD4030_REG_EXIT_CFG_MODE, + AD4030_REG_EXIT_CFG_MODE_EXIT_MSK); +} + +static int ad4030_get_chan_gain(struct iio_dev *indio_dev, int ch, int *val, + int *val2) +{ + struct ad4030_state *st = iio_priv(indio_dev); + u16 gain; + int ret; + + ret = regmap_bulk_read(st->regmap, AD4030_REG_GAIN_CHAN(ch), + st->rx_data.raw, AD4030_REG_GAIN_BYTES_NB); + if (ret) + return ret; + + gain = be16_to_cpu(*(u16 *)st->rx_data.raw); + + /* From datasheet: multiplied output = input × gain word/0x8000 */ + *val = gain / 0x8000; + *val2 = mul_u64_u32_div(gain % 0x8000, MICRO, 0x8000); + + return 0; +} + +/* + * @brief Returns the offset where 1 LSB = (VREF/2^precision_bits - 1)/gain + */ +static int ad4030_get_chan_offset(struct iio_dev *indio_dev, int ch, int *val) +{ + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + ret = regmap_bulk_read(st->regmap, AD4030_REG_OFFSET_CHAN(ch), + st->rx_data.raw, AD4030_REG_OFFSET_BYTES_NB); + if (ret) + return ret; + + switch (st->chip->precision_bits) { + case 16: + *val = sign_extend32(get_unaligned_be16(st->rx_data.raw), 15); + break; + + case 24: + *val = sign_extend32(get_unaligned_be24(st->rx_data.raw), 23); + break; + + default: + return -EINVAL; + } + + return 0; +} + +static int ad4030_set_chan_gain(struct iio_dev *indio_dev, int ch, int gain_int, + int gain_frac) +{ + struct ad4030_state *st = iio_priv(indio_dev); + __be16 *val = (__be16 *)st->rx_data.raw; + u64 gain; + + gain = mul_u32_u32(gain_int, MICRO) + gain_frac; + + if (gain > AD4030_REG_GAIN_MAX_GAIN) + return -EINVAL; + + *val = cpu_to_be16(DIV_ROUND_CLOSEST_ULL(gain * 0x8000, MICRO)); + + return regmap_bulk_write(st->regmap, AD4030_REG_GAIN_CHAN(ch), val, + AD4030_REG_GAIN_BYTES_NB); +} + +static int ad4030_set_chan_offset(struct iio_dev *indio_dev, int ch, int offset) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + if (offset < st->offset_avail[0] || offset > st->offset_avail[2]) + return -EINVAL; + + switch (st->chip->precision_bits) { + case 16: + put_unaligned_be16(offset, st->rx_data.raw); + break; + + case 24: + put_unaligned_be24(offset, st->rx_data.raw); + break; + + default: + return -EINVAL; + } + + return regmap_bulk_write(st->regmap, AD4030_REG_OFFSET_CHAN(ch), + st->rx_data.raw, AD4030_REG_OFFSET_BYTES_NB); +} + +static bool ad4030_is_common_byte_asked(struct ad4030_state *st, + unsigned int mask) +{ + /* Common byte channel is after the "real" differential sample channel */ + return mask & AD4030_COMMON_BYTE_CHANNELS_FILTER; +} + +static int ad4030_set_mode(struct iio_dev *indio_dev, unsigned long mask) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + if (ad4030_is_common_byte_asked(st, mask)) + st->mode = AD4030_OUT_DATA_MD_24_DIFF_8_COM; + else + st->mode = AD4030_OUT_DATA_MD_24_DIFF; + + return regmap_update_bits(st->regmap, AD4030_REG_MODES, + AD4030_REG_MODES_MASK_OUT_DATA_MODE, + st->mode); +} + +static int ad4030_conversion(struct ad4030_state *st, + const struct iio_chan_spec *chan) +{ + unsigned int bytes_to_read; + unsigned char byte_index; + unsigned int i; + int ret; + + /* Number of bytes for one differential channel */ + bytes_to_read = BITS_TO_BYTES(chan->scan_type.realbits); + /* Add one byte if we are using a differential + common byte mode */ + bytes_to_read += (st->mode == AD4030_OUT_DATA_MD_24_DIFF_8_COM || + st->mode == AD4030_OUT_DATA_MD_16_DIFF_8_COM) ? 1 : 0; + /* Mulitiply by the number of hardware channels */ + bytes_to_read *= st->chip->num_channels; + + gpiod_set_value_cansleep(st->cnv_gpio, 1); + ndelay(AD4030_TCNVH_NS); + gpiod_set_value_cansleep(st->cnv_gpio, 0); + ndelay(st->chip->tcyc); + + ret = spi_read(st->spi, st->rx_data.raw, bytes_to_read); + if (ret) + return ret; + + if (st->mode != AD4030_OUT_DATA_MD_24_DIFF_8_COM) + return 0; + + byte_index = BITS_TO_BYTES(chan->scan_type.realbits); + for (i = 0; i < st->chip->num_channels; i++) + st->rx_data.buffered[i].common = ((u8 *)&st->rx_data.buffered[i].val)[byte_index]; + + return 0; +} + +static int ad4030_single_conversion(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, int *val) +{ + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + ret = ad4030_set_mode(indio_dev, BIT(chan->channel)); + if (ret) + return ret; + + ret = ad4030_exit_config_mode(st); + if (ret) + goto out_exit_config_mode_error; + + ret = ad4030_conversion(st, chan); + if (ret) + goto out_error; + + if (chan->channel % 2) + *val = st->rx_data.buffered[chan->channel / 2].common; + else + *val = st->rx_data.buffered[chan->channel / 2].val; + +out_error: + ad4030_enter_config_mode(st); + +out_exit_config_mode_error: + + if (ret) + return ret; + + return IIO_VAL_INT; +} + +static irqreturn_t ad4030_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + ret = ad4030_conversion(st, indio_dev->channels); + if (ret) + goto out; + + iio_push_to_buffers_with_timestamp(indio_dev, st->rx_data.raw, + pf->timestamp); + +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static const int *ad4030_get_offset_avail(struct ad4030_state *st) +{ + return st->offset_avail; +} + +static const int ad4030_gain_avail[3][2] = { + { 0, 0 }, + { 0, 30 }, + { 1, 999969 }, +}; + +static int ad4030_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, + const int **vals, int *type, + int *length, long mask) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_CALIBBIAS: + *vals = ad4030_get_offset_avail(st); + *type = IIO_VAL_INT; + return IIO_AVAIL_RANGE; + + case IIO_CHAN_INFO_CALIBSCALE: + *vals = (void *)ad4030_gain_avail; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_RANGE; + + default: + return -EINVAL; + } +} + +static int ad4030_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long info) +{ + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + switch (info) { + case IIO_CHAN_INFO_RAW: + return ad4030_single_conversion(indio_dev, chan, val); + + case IIO_CHAN_INFO_SCALE: + *val = (st->vref_uv * 2) / MILLI; + *val2 = st->chip->precision_bits; + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_CALIBSCALE: + ret = ad4030_get_chan_gain(indio_dev, chan->channel, + val, val2); + if (ret) + return ret; + return IIO_VAL_INT_PLUS_MICRO; + + case IIO_CHAN_INFO_CALIBBIAS: + ret = ad4030_get_chan_offset(indio_dev, chan->channel, + val); + if (ret) + return ret; + return IIO_VAL_INT; + + default: + return -EINVAL; + } + } + + unreachable(); +} + +static int ad4030_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long info) +{ + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + switch (info) { + case IIO_CHAN_INFO_CALIBSCALE: + return ad4030_set_chan_gain(indio_dev, chan->channel, + val, val2); + + case IIO_CHAN_INFO_CALIBBIAS: + return ad4030_set_chan_offset(indio_dev, chan->channel, + val); + + default: + return -EINVAL; + } + } + + unreachable(); +} + +static int ad4030_reg_access(struct iio_dev *indio_dev, unsigned int reg, + unsigned int writeval, unsigned int *readval) +{ + const struct ad4030_state *st = iio_priv(indio_dev); + + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + if (readval) + return regmap_read(st->regmap, reg, readval); + + return regmap_write(st->regmap, reg, writeval); + } + + unreachable(); +} + +static const struct iio_info ad4030_iio_info = { + .read_avail = ad4030_read_avail, + .read_raw = ad4030_read_raw, + .write_raw = ad4030_write_raw, + .debugfs_reg_access = ad4030_reg_access, +}; + +static int ad4030_buffer_preenable(struct iio_dev *indio_dev) +{ + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + ret = ad4030_set_mode(indio_dev, *indio_dev->active_scan_mask); + if (ret) + return ret; + + ret = ad4030_exit_config_mode(st); + if (ret) + return ret; + + /* Restore SPI max speed for conversion */ + st->spi->max_speed_hz = st->conversion_speed_hz; + + return 0; +} + +static int ad4030_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + /* Make sure the SPI clock is within range to read register */ + st->spi->max_speed_hz = min(st->spi->max_speed_hz, + AD4030_SPI_MAX_REG_XFER_SPEED); + + return ad4030_enter_config_mode(st); +} + +static const struct iio_buffer_setup_ops ad4030_buffer_setup_ops = { + .preenable = ad4030_buffer_preenable, + .postdisable = ad4030_buffer_postdisable, +}; + +static int ad4030_regulators_get(struct ad4030_state *st) +{ + struct device *dev = &st->spi->dev; + static const char * const ids[] = { "vdd-5v", "vdd-1v8" }; + int ret; + + ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ids), ids); + if (ret) + return dev_err_probe(dev, ret, "Failed to enable regulators\n"); + + st->vio_uv = devm_regulator_get_enable_read_voltage(dev, "vio"); + if (st->vio_uv < 0) + return dev_err_probe(dev, st->vio_uv, + "Failed to enable and read vio voltage\n"); + + st->vref_uv = devm_regulator_get_enable_read_voltage(dev, "ref"); + if (st->vref_uv < 0) { + if (st->vref_uv != -ENODEV) + return dev_err_probe(dev, st->vref_uv, + "Failed to read vref voltage\n"); + + /* if not using optional REF, the internal REFIN must be used */ + st->vref_uv = devm_regulator_get_enable_read_voltage(dev, "refin"); + if (st->vref_uv < 0) + return dev_err_probe(dev, st->vref_uv, + "Failed to read vrefin voltage\n"); + } + + if (st->vref_uv < AD4030_VREF_MIN_UV || st->vref_uv > AD4030_VREF_MAX_UV) + return dev_err_probe(dev, -EINVAL, + "vref(%d) must be in the range [%lu %lu]\n", + st->vref_uv, AD4030_VREF_MIN_UV, + AD4030_VREF_MAX_UV); + + return 0; +} + +static int ad4030_reset(struct ad4030_state *st) +{ + struct device *dev = &st->spi->dev; + struct gpio_desc *reset; + int ret; + + /* Use GPIO if available ... */ + reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(reset)) + return dev_err_probe(dev, PTR_ERR(reset), + "Failed to get reset GPIO\n"); + + if (reset) { + ndelay(50); + gpiod_set_value_cansleep(reset, 0); + } else { + /* ... falback to software reset otherwise */ + ret = ad4030_enter_config_mode(st); + if (ret) + return ret; + + ret = regmap_write(st->regmap, AD4030_REG_INTERFACE_CONFIG_A, + AD4030_REG_INTERFACE_CONFIG_A_SW_RESET); + if (ret) + return ret; + } + + /* Wait for reset to complete before communicating to it */ + fsleep(AD4030_TRESET_COM_DELAY_MS); + + /* After reset, conversion mode is enabled. Switch to reg access */ + return ad4030_enter_config_mode(st); +} + +static int ad4030_detect_chip_info(const struct ad4030_state *st) +{ + unsigned int grade; + int ret; + + ret = regmap_read(st->regmap, AD4030_REG_CHIP_GRADE, &grade); + if (ret) + return ret; + + grade = FIELD_GET(AD4030_REG_CHIP_GRADE_MASK_CHIP_GRADE, grade); + if (grade != st->chip->grade) + return dev_err_probe(&st->spi->dev, -EINVAL, + "Unknown grade(0x%x) for %s\n", grade, + st->chip->name); + + return 0; +} + +static int ad4030_config(struct ad4030_state *st) +{ + st->offset_avail[0] = (int)BIT(st->chip->precision_bits - 1) * -1; + st->offset_avail[1] = 1; + st->offset_avail[2] = BIT(st->chip->precision_bits - 1) - 1; + + if (st->vio_uv < AD4030_VIO_THRESHOLD_UV) + return regmap_write(st->regmap, AD4030_REG_IO, + AD4030_REG_IO_MASK_IO2X); + + return 0; +} + +static int ad4030_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct iio_dev *indio_dev; + struct ad4030_state *st; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi = spi; + + /* Make sure the SPI clock is within range to read register */ + st->conversion_speed_hz = min(spi->max_speed_hz, + AD4030_SPI_MAX_REG_XFER_SPEED); + + st->regmap = devm_regmap_init(dev, &ad4030_regmap_bus, st, + &ad4030_regmap_config); + if (IS_ERR(st->regmap)) + dev_err_probe(dev, PTR_ERR(st->regmap), + "Failed to initialize regmap\n"); + + st->chip = spi_get_device_match_data(spi); + if (!st->chip) + return -EINVAL; + + ret = ad4030_regulators_get(st); + if (ret) + return ret; + + ret = ad4030_reset(st); + if (ret) + return ret; + + ret = ad4030_detect_chip_info(st); + if (ret) + return ret; + + ret = ad4030_config(st); + if (ret) + return ret; + + st->cnv_gpio = devm_gpiod_get(dev, "cnv", GPIOD_OUT_LOW); + if (IS_ERR(st->cnv_gpio)) + return dev_err_probe(dev, PTR_ERR(st->cnv_gpio), + "Failed to get cnv gpio\n"); + + /* + * One hardware channel is split in two software channels when using + * common byte mode. Add one more channel for the timestamp. + */ + indio_dev->num_channels = 2 * st->chip->num_channels + 1; + indio_dev->name = st->chip->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &ad4030_iio_info; + indio_dev->channels = st->chip->channels; + indio_dev->available_scan_masks = st->chip->available_masks; + indio_dev->masklength = st->chip->available_masks_len; + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, + iio_pollfunc_store_time, + ad4030_trigger_handler, + &ad4030_buffer_setup_ops); + if (ret) + return dev_err_probe(dev, ret, "Failed to setup triggered buffer\n"); + + return devm_iio_device_register(dev, indio_dev); +} + +static const unsigned long ad4030_channel_masks[] = { + /* Differential only */ + BIT(0), + /* Differential with common byte */ + GENMASK(1, 0), + 0, +}; + +static const struct ad4030_chip_info ad4030_24_chip_info = { + .name = "ad4030-24", + .available_masks = ad4030_channel_masks, + .available_masks_len = ARRAY_SIZE(ad4030_channel_masks), + .channels = { + AD4030_CHAN_IN(0, 32, 24, 8), + AD4030_CHAN_CMO(0), + IIO_CHAN_SOFT_TIMESTAMP(2), + }, + .grade = AD4030_REG_CHIP_GRADE_AD4030_24_GRADE, + .precision_bits = 24, + .num_channels = 1, + .tcyc = AD4030_TCYC_ADJUSTED_NS, +}; + +static const struct spi_device_id ad4030_id_table[] = { + { "ad4030-24", (kernel_ulong_t)&ad4030_24_chip_info }, + {} +}; +MODULE_DEVICE_TABLE(spi, ad4030_id_table); + +static const struct of_device_id ad4030_of_match[] = { + { .compatible = "adi,ad4030-24", .data = &ad4030_24_chip_info }, + {} +}; +MODULE_DEVICE_TABLE(of, ad4030_of_match); + +static struct spi_driver ad4030_driver = { + .driver = { + .name = "ad4030", + .of_match_table = ad4030_of_match, + }, + .probe = ad4030_probe, + .id_table = ad4030_id_table, +}; +module_spi_driver(ad4030_driver); + +MODULE_AUTHOR("Esteban Blanc <eblanc@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices AD4630 ADC family driver"); +MODULE_LICENSE("GPL"); -- 2.44.1
