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 | 14 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad4030.c | 926 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 942 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index f17ead8c1e7b9abd2ae406494a24e117fb76435a..943c48fc0a75f475049758cf3791ba6d19748a63 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1282,6 +1282,7 @@ L: linux-iio@xxxxxxxxxxxxxxx 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 ANALOG DEVICES INC AD4130 DRIVER M: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 849c90203071a77ec7d94cec06d4378ece44440b..9677343a3269db6405dfdd4e938423806c891b47 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -33,6 +33,20 @@ config AD4000 To compile this driver as a module, choose M here: the module will be called ad4000. +config AD4030 + tristate "Analog Devices AD4030 ADC Driver" + depends on SPI + depends on GPIOLIB + select REGMAP + select IIO_BUFFER + select IIO_TRIGGERED_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 ee19afba62b7fe0a68309c16f3581d98c5b8f653..326536bb672da3d6229b66af13874d122b2f7b94 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 0000000000000000000000000000000000000000..feb98a0fdbeb3e48cd356d817a5dda6d23f5ed3f --- /dev/null +++ b/drivers/iio/adc/ad4030.c @@ -0,0 +1,926 @@ +// 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/clk.h> +#include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> +#include <linux/units.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_SINGLE_COMMON_BYTE_CHANNELS_MASK 0b10 +/* + * This accounts for 1 sample per channel plus one s64 for the timestamp, + * aligned on a s64 boundary + */ +#define AD4030_MAXIMUM_RX_BUFFER_SIZE \ + (ALIGN(AD4030_MAX_IIO_SAMPLE_SIZE_BUFFERED * \ + AD4030_MAX_HARDWARE_CHANNEL_NB, \ + sizeof(s64)) + sizeof(s64)) + +#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 + +enum ad4030_out_mode { + AD4030_OUT_DATA_MD_DIFF, + AD4030_OUT_DATA_MD_16_DIFF_8_COM, + AD4030_OUT_DATA_MD_24_DIFF_8_COM, + AD4030_OUT_DATA_MD_30_AVERAGED_DIFF, + AD4030_OUT_DATA_MD_32_PATTERN +}; + +struct ad4030_chip_info { + const char *name; + const unsigned long *available_masks; + const struct iio_chan_spec channels[AD4030_MAX_IIO_CHANNEL_NB]; + u8 grade; + u8 precision_bits; + /* Number of hardware channels */ + int num_voltage_inputs; + unsigned int tcyc_ns; +}; + +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]; + 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); + union { + u8 raw[AD4030_MAXIMUM_RX_BUFFER_SIZE]; + struct { + s32 diff; + u8 common; + }; + } rx_data; +}; + +/* + * For a chip with 2 hardware channel this will be used to create 2 common-mode + * channels: + * - voltage4 + * - voltage5 + * As the common-mode channels are after the differential ones, we compute the + * channel number like this: + * - _idx is the scan_index (the order in the output buffer) + * - _ch is the hardware channel number this common-mode channel is related + * - _idx - _ch gives us the number of channel in the chip + * - _idx - _ch * 2 is the starting number of the common-mode channels, since + * for each differential channel there is a common-mode channel + * - _idx - _ch * 2 + _ch gives the channel number for this specific common-mode + * channel + */ +#define AD4030_CHAN_CMO(_idx, _ch) { \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE), \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .address = (_ch), \ + .channel = ((_idx) - (_ch)) * 2 + (_ch), \ + .scan_index = (_idx), \ + .scan_type = { \ + .sign = 'u', \ + .storagebits = 8, \ + .realbits = 8, \ + .endianness = IIO_BE, \ + }, \ +} + +/* + * For a chip with 2 hardware channel this will be used to create 2 differential + * channels: + * - voltage0-voltage1 + * - voltage2-voltage3 + */ +#define AD4030_CHAN_DIFF(_idx, _storage, _real, _shift) { \ + .info_mask_separate = BIT(IIO_CHAN_INFO_SCALE) | \ + 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, \ + .address = (_idx), \ + .channel = (_idx) * 2, \ + .channel2 = (_idx) * 2 + 1, \ + .scan_index = (_idx), \ + .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) +{ + int ret; + 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, + .speed_hz = AD4030_SPI_MAX_REG_XFER_SPEED, + }; + + if (xfer.len > ARRAY_SIZE(st->tx_data) || + xfer.len > ARRAY_SIZE(st->rx_data.raw)) + return -EINVAL; + + memset(st->tx_data, 0, ARRAY_SIZE(st->tx_data)); + memcpy(st->tx_data, reg, reg_size); + + 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) +{ + struct ad4030_state *st = context; + + struct spi_transfer xfer = { + .tx_buf = st->tx_data, + .len = count, + .speed_hz = AD4030_SPI_MAX_REG_XFER_SPEED, + }; + + if (count > ARRAY_SIZE(st->tx_data)) + return -EINVAL; + + memcpy(st->tx_data, data, count); + + return spi_sync_transfer(st->spi, &xfer, 1); +} + +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->tx_data[0] = AD4030_REG_ACCESS; + + struct spi_transfer xfer = { + .tx_buf = st->tx_data, + .len = 1, + .speed_hz = AD4030_SPI_MAX_REG_XFER_SPEED, + }; + + return spi_sync_transfer(st->spi, &xfer, 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_scale(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + if (chan->differential) { + *val = (st->vref_uv * 2) / MILLI; + *val2 = st->chip->precision_bits; + return IIO_VAL_FRACTIONAL_LOG2; + } + + *val = st->vref_uv / 256; + return IIO_VAL_INT; +} + +static int ad4030_get_chan_calibscale(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + 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(chan->address), + st->rx_data.raw, AD4030_REG_GAIN_BYTES_NB); + if (ret) + return ret; + + gain = get_unaligned_be16(st->rx_data.raw); + + /* From datasheet: multiplied output = input × gain word/0x8000 */ + *val = gain / 0x8000; + *val2 = mul_u64_u32_div(gain % 0x8000, NANO, 0x8000); + + return IIO_VAL_INT_PLUS_NANO; +} + +/* Returns the offset where 1 LSB = (VREF/2^precision_bits - 1)/gain */ +static int ad4030_get_chan_calibbias(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val) +{ + struct ad4030_state *st = iio_priv(indio_dev); + int ret; + + ret = regmap_bulk_read(st->regmap, + AD4030_REG_OFFSET_CHAN(chan->address), + 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); + return IIO_VAL_INT; + + case 24: + *val = sign_extend32(get_unaligned_be24(st->rx_data.raw), 23); + return IIO_VAL_INT; + + default: + return -EINVAL; + } +} + +static int ad4030_set_chan_calibscale(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int gain_int, + int gain_frac) +{ + struct ad4030_state *st = iio_priv(indio_dev); + u64 gain; + + if (gain_int < 0 || gain_frac < 0) + return -EINVAL; + + gain = mul_u32_u32(gain_int, MICRO) + gain_frac; + + if (gain > AD4030_REG_GAIN_MAX_GAIN) + return -EINVAL; + + put_unaligned_be16(DIV_ROUND_CLOSEST_ULL(gain * 0x8000, MICRO), + st->tx_data); + + return regmap_bulk_write(st->regmap, + AD4030_REG_GAIN_CHAN(chan->address), + st->tx_data, AD4030_REG_GAIN_BYTES_NB); +} + +static int ad4030_set_chan_calibbias(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int offset) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + if (offset < st->offset_avail[0] || offset > st->offset_avail[2]) + return -EINVAL; + + st->tx_data[2] = 0; + + switch (st->chip->precision_bits) { + case 16: + put_unaligned_be16(offset, st->tx_data); + break; + + case 24: + put_unaligned_be24(offset, st->tx_data); + break; + + default: + return -EINVAL; + } + + return regmap_bulk_write(st->regmap, + AD4030_REG_OFFSET_CHAN(chan->address), + st->tx_data, AD4030_REG_OFFSET_BYTES_NB); +} + +static bool ad4030_is_common_byte_asked(struct ad4030_state *st, + unsigned int mask) +{ + return mask & AD4030_SINGLE_COMMON_BYTE_CHANNELS_MASK; +} + +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_DIFF; + + return regmap_update_bits(st->regmap, AD4030_REG_MODES, + AD4030_REG_MODES_MASK_OUT_DATA_MODE, + st->mode); +} + +static int ad4030_conversion(struct iio_dev *indio_dev) +{ + struct ad4030_state *st = iio_priv(indio_dev); + const struct iio_scan_type scan_type = indio_dev->channels->scan_type; + unsigned char diff_realbytes = BITS_TO_BYTES(scan_type.realbits); + unsigned int bytes_to_read; + int ret; + + /* Number of bytes for one differential channel */ + bytes_to_read = diff_realbytes; + /* 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_voltage_inputs; + + gpiod_set_value_cansleep(st->cnv_gpio, 1); + ndelay(AD4030_TCNVH_NS); + gpiod_set_value_cansleep(st->cnv_gpio, 0); + ndelay(st->chip->tcyc_ns); + + 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; + + st->rx_data.common = st->rx_data.raw[diff_realbytes]; + + 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->scan_index)); + if (ret) + return ret; + + ret = ad4030_exit_config_mode(st); + if (ret) + goto out_error; + + ret = ad4030_conversion(indio_dev); + if (ret) + goto out_error; + + if (chan->differential) + *val = st->rx_data.diff; + else + *val = st->rx_data.common; + + ad4030_enter_config_mode(st); + + return IIO_VAL_INT; + +out_error: + ad4030_enter_config_mode(st); + + return ret; +} + +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(indio_dev); + 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_gain_avail[3][2] = { + { 0, 0 }, + { 0, 30518 }, + { 1, 999969482 }, +}; + +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 = st->offset_avail; + *type = IIO_VAL_INT; + return IIO_AVAIL_RANGE; + + case IIO_CHAN_INFO_CALIBSCALE: + *vals = (void *)ad4030_gain_avail; + *type = IIO_VAL_INT_PLUS_NANO; + return IIO_AVAIL_RANGE; + + default: + return -EINVAL; + } +} + +static int ad4030_read_raw_dispatch(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long info) +{ + switch (info) { + case IIO_CHAN_INFO_RAW: + return ad4030_single_conversion(indio_dev, chan, val); + + case IIO_CHAN_INFO_CALIBSCALE: + return ad4030_get_chan_calibscale(indio_dev, chan, val, val2); + + case IIO_CHAN_INFO_CALIBBIAS: + return ad4030_get_chan_calibbias(indio_dev, chan, val); + + 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) +{ + int ret; + + if (info == IIO_CHAN_INFO_SCALE) + return ad4030_get_chan_scale(indio_dev, chan, val, val2); + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + ret = ad4030_read_raw_dispatch(indio_dev, chan, val, val2, info); + + iio_device_release_direct_mode(indio_dev); + + return ret; +} + +static int ad4030_write_raw_dispatch(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long info) +{ + switch (info) { + case IIO_CHAN_INFO_CALIBSCALE: + return ad4030_set_chan_calibscale(indio_dev, chan, val, val2); + + case IIO_CHAN_INFO_CALIBBIAS: + if (val2 != 0) + return -EINVAL; + return ad4030_set_chan_calibbias(indio_dev, chan, val); + + default: + return -EINVAL; + } +} + +static int ad4030_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long info) +{ + int ret; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + ret = ad4030_write_raw_dispatch(indio_dev, chan, val, val2, info); + + iio_device_release_direct_mode(indio_dev); + + return ret; +} + +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); + int ret; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + if (readval) + ret = regmap_read(st->regmap, reg, readval); + else + ret = regmap_write(st->regmap, reg, writeval); + + iio_device_release_direct_mode(indio_dev); + + return ret; +} + +static int ad4030_read_label(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + char *label) +{ + if (chan->differential) + return sprintf(label, "differential%lu\n", chan->address); + return sprintf(label, "common-mode%lu\n", chan->address); +} + +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, + .read_label = ad4030_read_label, +}; + +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; + + return 0; +} + +static int ad4030_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct ad4030_state *st = iio_priv(indio_dev); + + 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 ref 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 refin voltage\n"); + } + + return 0; +} + +static int ad4030_reset(struct ad4030_state *st) +{ + struct device *dev = &st->spi->dev; + struct gpio_desc *reset; + int ret; + + 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 { + 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; + } + + /* + * From datasheet: "After a [...] reset, no SPI commands or conversions + * can be started for 750us" + */ + fsleep(750); + + /* 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) + dev_warn(&st->spi->dev, "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; + + 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; + + /* + * From datasheet: "Perform a reset no sooner than 3ms after the power + * supplies are valid and stable" + */ + fsleep(3000); + + 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_voltage_inputs + 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; + + 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 and common-mode voltage */ + GENMASK(1, 0), + 0, +}; + +static const struct ad4030_chip_info ad4030_24_chip_info = { + .name = "ad4030-24", + .available_masks = ad4030_channel_masks, + .channels = { + AD4030_CHAN_DIFF(0, 32, 24, 8), + AD4030_CHAN_CMO(1, 0), + IIO_CHAN_SOFT_TIMESTAMP(2), + }, + .grade = AD4030_REG_CHIP_GRADE_AD4030_24_GRADE, + .precision_bits = 24, + .num_voltage_inputs = 1, + .tcyc_ns = 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"); -- 2.47.0
