diff options
Diffstat (limited to 'drivers/iio/adc/ad7380.c')
| -rw-r--r-- | drivers/iio/adc/ad7380.c | 833 |
1 files changed, 833 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad7380.c b/drivers/iio/adc/ad7380.c new file mode 100644 index 000000000000..7568cd0a2b32 --- /dev/null +++ b/drivers/iio/adc/ad7380.c @@ -0,0 +1,833 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD738x Simultaneous Sampling SAR ADCs + * + * Copyright 2017 Analog Devices Inc. + * Copyright 2024 BayLibre, SAS + * + * Datasheets of supported parts: + * ad7380/1 : https://www.analog.com/media/en/technical-documentation/data-sheets/AD7380-7381.pdf + * ad7383/4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7383-7384.pdf + * ad7380-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7380-4.pdf + * ad7381-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7381-4.pdf + * ad7383/4-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7383-4-ad7384-4.pdf + */ + +#include <linux/align.h> +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/cleanup.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define MAX_NUM_CHANNELS 4 +/* 2.5V internal reference voltage */ +#define AD7380_INTERNAL_REF_MV 2500 + +/* reading and writing registers is more reliable at lower than max speed */ +#define AD7380_REG_WR_SPEED_HZ 10000000 + +#define AD7380_REG_WR BIT(15) +#define AD7380_REG_REGADDR GENMASK(14, 12) +#define AD7380_REG_DATA GENMASK(11, 0) + +#define AD7380_REG_ADDR_NOP 0x0 +#define AD7380_REG_ADDR_CONFIG1 0x1 +#define AD7380_REG_ADDR_CONFIG2 0x2 +#define AD7380_REG_ADDR_ALERT 0x3 +#define AD7380_REG_ADDR_ALERT_LOW_TH 0x4 +#define AD7380_REG_ADDR_ALERT_HIGH_TH 0x5 + +#define AD7380_CONFIG1_OS_MODE BIT(9) +#define AD7380_CONFIG1_OSR GENMASK(8, 6) +#define AD7380_CONFIG1_CRC_W BIT(5) +#define AD7380_CONFIG1_CRC_R BIT(4) +#define AD7380_CONFIG1_ALERTEN BIT(3) +#define AD7380_CONFIG1_RES BIT(2) +#define AD7380_CONFIG1_REFSEL BIT(1) +#define AD7380_CONFIG1_PMODE BIT(0) + +#define AD7380_CONFIG2_SDO2 GENMASK(9, 8) +#define AD7380_CONFIG2_SDO BIT(8) +#define AD7380_CONFIG2_RESET GENMASK(7, 0) + +#define AD7380_CONFIG2_RESET_SOFT 0x3C +#define AD7380_CONFIG2_RESET_HARD 0xFF + +#define AD7380_ALERT_LOW_TH GENMASK(11, 0) +#define AD7380_ALERT_HIGH_TH GENMASK(11, 0) + +#define T_CONVERT_NS 190 /* conversion time */ +#define T_CONVERT_0_NS 10 /* 1st conversion start time (oversampling) */ +#define T_CONVERT_X_NS 500 /* xth conversion start time (oversampling) */ + +struct ad7380_timing_specs { + const unsigned int t_csh_ns; /* CS minimum high time */ +}; + +struct ad7380_chip_info { + const char *name; + const struct iio_chan_spec *channels; + unsigned int num_channels; + const char * const *vcm_supplies; + unsigned int num_vcm_supplies; + const unsigned long *available_scan_masks; + const struct ad7380_timing_specs *timing_specs; +}; + +enum { + AD7380_SCAN_TYPE_NORMAL, + AD7380_SCAN_TYPE_RESOLUTION_BOOST, +}; + +/* Extended scan types for 14-bit chips. */ +static const struct iio_scan_type ad7380_scan_type_14[] = { + [AD7380_SCAN_TYPE_NORMAL] = { + .sign = 's', + .realbits = 14, + .storagebits = 16, + .endianness = IIO_CPU + }, + [AD7380_SCAN_TYPE_RESOLUTION_BOOST] = { + .sign = 's', + .realbits = 16, + .storagebits = 16, + .endianness = IIO_CPU + }, +}; + +/* Extended scan types for 16-bit chips. */ +static const struct iio_scan_type ad7380_scan_type_16[] = { + [AD7380_SCAN_TYPE_NORMAL] = { + .sign = 's', + .realbits = 16, + .storagebits = 16, + .endianness = IIO_CPU + }, + [AD7380_SCAN_TYPE_RESOLUTION_BOOST] = { + .sign = 's', + .realbits = 18, + .storagebits = 32, + .endianness = IIO_CPU + }, +}; + +#define AD7380_CHANNEL(index, bits, diff) { \ + .type = IIO_VOLTAGE, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + ((diff) ? 0 : BIT(IIO_CHAN_INFO_OFFSET)), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ + .info_mask_shared_by_type_available = \ + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ + .indexed = 1, \ + .differential = (diff), \ + .channel = (diff) ? (2 * (index)) : (index), \ + .channel2 = (diff) ? (2 * (index) + 1) : 0, \ + .scan_index = (index), \ + .has_ext_scan_type = 1, \ + .ext_scan_type = ad7380_scan_type_##bits, \ + .num_ext_scan_type = ARRAY_SIZE(ad7380_scan_type_##bits),\ +} + +#define DEFINE_AD7380_2_CHANNEL(name, bits, diff) \ +static const struct iio_chan_spec name[] = { \ + AD7380_CHANNEL(0, bits, diff), \ + AD7380_CHANNEL(1, bits, diff), \ + IIO_CHAN_SOFT_TIMESTAMP(2), \ +} + +#define DEFINE_AD7380_4_CHANNEL(name, bits, diff) \ +static const struct iio_chan_spec name[] = { \ + AD7380_CHANNEL(0, bits, diff), \ + AD7380_CHANNEL(1, bits, diff), \ + AD7380_CHANNEL(2, bits, diff), \ + AD7380_CHANNEL(3, bits, diff), \ + IIO_CHAN_SOFT_TIMESTAMP(4), \ +} + +/* fully differential */ +DEFINE_AD7380_2_CHANNEL(ad7380_channels, 16, 1); +DEFINE_AD7380_2_CHANNEL(ad7381_channels, 14, 1); +DEFINE_AD7380_4_CHANNEL(ad7380_4_channels, 16, 1); +DEFINE_AD7380_4_CHANNEL(ad7381_4_channels, 14, 1); +/* pseudo differential */ +DEFINE_AD7380_2_CHANNEL(ad7383_channels, 16, 0); +DEFINE_AD7380_2_CHANNEL(ad7384_channels, 14, 0); +DEFINE_AD7380_4_CHANNEL(ad7383_4_channels, 16, 0); +DEFINE_AD7380_4_CHANNEL(ad7384_4_channels, 14, 0); + +static const char * const ad7380_2_channel_vcm_supplies[] = { + "aina", "ainb", +}; + +static const char * const ad7380_4_channel_vcm_supplies[] = { + "aina", "ainb", "ainc", "aind", +}; + +/* Since this is simultaneous sampling, we don't allow individual channels. */ +static const unsigned long ad7380_2_channel_scan_masks[] = { + GENMASK(1, 0), + 0 +}; + +static const unsigned long ad7380_4_channel_scan_masks[] = { + GENMASK(3, 0), + 0 +}; + +static const struct ad7380_timing_specs ad7380_timing = { + .t_csh_ns = 10, +}; + +static const struct ad7380_timing_specs ad7380_4_timing = { + .t_csh_ns = 20, +}; + +/* + * Available oversampling ratios. The indices correspond with the bit value + * expected by the chip. The available ratios depend on the averaging mode, + * only normal averaging is supported for now. + */ +static const int ad7380_oversampling_ratios[] = { + 1, 2, 4, 8, 16, 32, +}; + +static const struct ad7380_chip_info ad7380_chip_info = { + .name = "ad7380", + .channels = ad7380_channels, + .num_channels = ARRAY_SIZE(ad7380_channels), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, +}; + +static const struct ad7380_chip_info ad7381_chip_info = { + .name = "ad7381", + .channels = ad7381_channels, + .num_channels = ARRAY_SIZE(ad7381_channels), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, +}; + +static const struct ad7380_chip_info ad7383_chip_info = { + .name = "ad7383", + .channels = ad7383_channels, + .num_channels = ARRAY_SIZE(ad7383_channels), + .vcm_supplies = ad7380_2_channel_vcm_supplies, + .num_vcm_supplies = ARRAY_SIZE(ad7380_2_channel_vcm_supplies), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, +}; + +static const struct ad7380_chip_info ad7384_chip_info = { + .name = "ad7384", + .channels = ad7384_channels, + .num_channels = ARRAY_SIZE(ad7384_channels), + .vcm_supplies = ad7380_2_channel_vcm_supplies, + .num_vcm_supplies = ARRAY_SIZE(ad7380_2_channel_vcm_supplies), + .available_scan_masks = ad7380_2_channel_scan_masks, + .timing_specs = &ad7380_timing, +}; + +static const struct ad7380_chip_info ad7380_4_chip_info = { + .name = "ad7380-4", + .channels = ad7380_4_channels, + .num_channels = ARRAY_SIZE(ad7380_4_channels), + .available_scan_masks = ad7380_4_channel_scan_masks, + .timing_specs = &ad7380_4_timing, +}; + +static const struct ad7380_chip_info ad7381_4_chip_info = { + .name = "ad7381-4", + .channels = ad7381_4_channels, + .num_channels = ARRAY_SIZE(ad7381_4_channels), + .available_scan_masks = ad7380_4_channel_scan_masks, + .timing_specs = &ad7380_4_timing, +}; + +static const struct ad7380_chip_info ad7383_4_chip_info = { + .name = "ad7383-4", + .channels = ad7383_4_channels, + .num_channels = ARRAY_SIZE(ad7383_4_channels), + .vcm_supplies = ad7380_4_channel_vcm_supplies, + .num_vcm_supplies = ARRAY_SIZE(ad7380_4_channel_vcm_supplies), + .available_scan_masks = ad7380_4_channel_scan_masks, + .timing_specs = &ad7380_4_timing, +}; + +static const struct ad7380_chip_info ad7384_4_chip_info = { + .name = "ad7384-4", + .channels = ad7384_4_channels, + .num_channels = ARRAY_SIZE(ad7384_4_channels), + .vcm_supplies = ad7380_4_channel_vcm_supplies, + .num_vcm_supplies = ARRAY_SIZE(ad7380_4_channel_vcm_supplies), + .available_scan_masks = ad7380_4_channel_scan_masks, + .timing_specs = &ad7380_4_timing, +}; + +struct ad7380_state { + const struct ad7380_chip_info *chip_info; + struct spi_device *spi; + struct regmap *regmap; + unsigned int oversampling_ratio; + bool resolution_boost_enabled; + unsigned int vref_mv; + unsigned int vcm_mv[MAX_NUM_CHANNELS]; + /* xfers, message an buffer for reading sample data */ + struct spi_transfer xfer[2]; + struct spi_message msg; + /* + * DMA (thus cache coherency maintenance) requires the transfer buffers + * to live in their own cache lines. + * + * Make the buffer large enough for MAX_NUM_CHANNELS 32-bit samples and + * one 64-bit aligned 64-bit timestamp. + */ + u8 scan_data[ALIGN(MAX_NUM_CHANNELS * sizeof(u32), sizeof(s64)) + + sizeof(s64)] __aligned(IIO_DMA_MINALIGN); + /* buffers for reading/writing registers */ + u16 tx; + u16 rx; +}; + +static int ad7380_regmap_reg_write(void *context, unsigned int reg, + unsigned int val) +{ + struct ad7380_state *st = context; + struct spi_transfer xfer = { + .speed_hz = AD7380_REG_WR_SPEED_HZ, + .bits_per_word = 16, + .len = 2, + .tx_buf = &st->tx, + }; + + st->tx = FIELD_PREP(AD7380_REG_WR, 1) | + FIELD_PREP(AD7380_REG_REGADDR, reg) | + FIELD_PREP(AD7380_REG_DATA, val); + + return spi_sync_transfer(st->spi, &xfer, 1); +} + +static int ad7380_regmap_reg_read(void *context, unsigned int reg, + unsigned int *val) +{ + struct ad7380_state *st = context; + struct spi_transfer xfers[] = { + { + .speed_hz = AD7380_REG_WR_SPEED_HZ, + .bits_per_word = 16, + .len = 2, + .tx_buf = &st->tx, + .cs_change = 1, + .cs_change_delay = { + .value = st->chip_info->timing_specs->t_csh_ns, + .unit = SPI_DELAY_UNIT_NSECS, + }, + }, { + .speed_hz = AD7380_REG_WR_SPEED_HZ, + .bits_per_word = 16, + .len = 2, + .rx_buf = &st->rx, + }, + }; + int ret; + + st->tx = FIELD_PREP(AD7380_REG_WR, 0) | + FIELD_PREP(AD7380_REG_REGADDR, reg) | + FIELD_PREP(AD7380_REG_DATA, 0); + + ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers)); + if (ret < 0) + return ret; + + *val = FIELD_GET(AD7380_REG_DATA, st->rx); + + return 0; +} + +static const struct regmap_config ad7380_regmap_config = { + .reg_bits = 3, + .val_bits = 12, + .reg_read = ad7380_regmap_reg_read, + .reg_write = ad7380_regmap_reg_write, + .max_register = AD7380_REG_ADDR_ALERT_HIGH_TH, + .can_sleep = true, +}; + +static int ad7380_debugfs_reg_access(struct iio_dev *indio_dev, u32 reg, + u32 writeval, u32 *readval) +{ + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + struct ad7380_state *st = iio_priv(indio_dev); + + if (readval) + return regmap_read(st->regmap, reg, readval); + else + return regmap_write(st->regmap, reg, writeval); + } + unreachable(); +} + +/** + * ad7380_update_xfers - update the SPI transfers base on the current scan type + * @st: device instance specific state + * @scan_type: current scan type + */ +static void ad7380_update_xfers(struct ad7380_state *st, + const struct iio_scan_type *scan_type) +{ + /* + * First xfer only triggers conversion and has to be long enough for + * all conversions to complete, which can be multiple conversion in the + * case of oversampling. Technically T_CONVERT_X_NS is lower for some + * chips, but we use the maximum value for simplicity for now. + */ + if (st->oversampling_ratio > 1) + st->xfer[0].delay.value = T_CONVERT_0_NS + T_CONVERT_X_NS * + (st->oversampling_ratio - 1); + else + st->xfer[0].delay.value = T_CONVERT_NS; + + st->xfer[0].delay.unit = SPI_DELAY_UNIT_NSECS; + + /* + * Second xfer reads all channels. Data size depends on if resolution + * boost is enabled or not. + */ + st->xfer[1].bits_per_word = scan_type->realbits; + st->xfer[1].len = BITS_TO_BYTES(scan_type->storagebits) * + (st->chip_info->num_channels - 1); +} + +static int ad7380_triggered_buffer_preenable(struct iio_dev *indio_dev) +{ + struct ad7380_state *st = iio_priv(indio_dev); + const struct iio_scan_type *scan_type; + + /* + * Currently, we always read all channels at the same time. The scan_type + * is the same for all channels, so we just pass the first channel. + */ + scan_type = iio_get_current_scan_type(indio_dev, &indio_dev->channels[0]); + if (IS_ERR(scan_type)) + return PTR_ERR(scan_type); + + ad7380_update_xfers(st, scan_type); + + return spi_optimize_message(st->spi, &st->msg); +} + +static int ad7380_triggered_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct ad7380_state *st = iio_priv(indio_dev); + + spi_unoptimize_message(&st->msg); + + return 0; +} + +static const struct iio_buffer_setup_ops ad7380_buffer_setup_ops = { + .preenable = ad7380_triggered_buffer_preenable, + .postdisable = ad7380_triggered_buffer_postdisable, +}; + +static irqreturn_t ad7380_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct ad7380_state *st = iio_priv(indio_dev); + int ret; + + ret = spi_sync(st->spi, &st->msg); + if (ret) + goto out; + + iio_push_to_buffers_with_timestamp(indio_dev, &st->scan_data, + pf->timestamp); + +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int ad7380_read_direct(struct ad7380_state *st, unsigned int scan_index, + const struct iio_scan_type *scan_type, int *val) +{ + int ret; + + ad7380_update_xfers(st, scan_type); + + ret = spi_sync(st->spi, &st->msg); + if (ret < 0) + return ret; + + if (scan_type->storagebits > 16) + *val = sign_extend32(*(u32 *)(st->scan_data + 4 * scan_index), + scan_type->realbits - 1); + else + *val = sign_extend32(*(u16 *)(st->scan_data + 2 * scan_index), + scan_type->realbits - 1); + + return IIO_VAL_INT; +} + +static int ad7380_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long info) +{ + struct ad7380_state *st = iio_priv(indio_dev); + const struct iio_scan_type *scan_type; + + scan_type = iio_get_current_scan_type(indio_dev, chan); + + if (IS_ERR(scan_type)) + return PTR_ERR(scan_type); + + switch (info) { + case IIO_CHAN_INFO_RAW: + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + return ad7380_read_direct(st, chan->scan_index, + scan_type, val); + } + unreachable(); + case IIO_CHAN_INFO_SCALE: + /* + * According to the datasheet, the LSB size is: + * * (2 × VREF) / 2^N, for differential chips + * * VREF / 2^N, for pseudo-differential chips + * where N is the ADC resolution (i.e realbits) + */ + *val = st->vref_mv; + *val2 = scan_type->realbits - chan->differential; + + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OFFSET: + /* + * According to IIO ABI, offset is applied before scale, + * so offset is: vcm_mv / scale + */ + *val = st->vcm_mv[chan->channel] * (1 << scan_type->realbits) + / st->vref_mv; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = st->oversampling_ratio; + + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int ad7380_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *vals = ad7380_oversampling_ratios; + *length = ARRAY_SIZE(ad7380_oversampling_ratios); + *type = IIO_VAL_INT; + + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +/** + * ad7380_osr_to_regval - convert ratio to OSR register value + * @ratio: ratio to check + * + * Check if ratio is present in the list of available ratios and return the + * corresponding value that needs to be written to the register to select that + * ratio. + * + * Returns: register value (0 to 7) or -EINVAL if there is not an exact match + */ +static int ad7380_osr_to_regval(int ratio) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ad7380_oversampling_ratios); i++) { + if (ratio == ad7380_oversampling_ratios[i]) + return i; + } + + return -EINVAL; +} + +static int ad7380_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct ad7380_state *st = iio_priv(indio_dev); + int ret, osr, boost; + + switch (mask) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + osr = ad7380_osr_to_regval(val); + if (osr < 0) + return osr; + + /* always enable resolution boost when oversampling is enabled */ + boost = osr > 0 ? 1 : 0; + + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) { + ret = regmap_update_bits(st->regmap, + AD7380_REG_ADDR_CONFIG1, + AD7380_CONFIG1_OSR | AD7380_CONFIG1_RES, + FIELD_PREP(AD7380_CONFIG1_OSR, osr) | + FIELD_PREP(AD7380_CONFIG1_RES, boost)); + + if (ret) + return ret; + + st->oversampling_ratio = val; + st->resolution_boost_enabled = boost; + + /* + * Perform a soft reset. This will flush the oversampling + * block and FIFO but will maintain the content of the + * configurable registers. + */ + return regmap_update_bits(st->regmap, + AD7380_REG_ADDR_CONFIG2, + AD7380_CONFIG2_RESET, + FIELD_PREP(AD7380_CONFIG2_RESET, + AD7380_CONFIG2_RESET_SOFT)); + } + unreachable(); + default: + return -EINVAL; + } +} + +static int ad7380_get_current_scan_type(const struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad7380_state *st = iio_priv(indio_dev); + + return st->resolution_boost_enabled ? AD7380_SCAN_TYPE_RESOLUTION_BOOST + : AD7380_SCAN_TYPE_NORMAL; +} + +static const struct iio_info ad7380_info = { + .read_raw = &ad7380_read_raw, + .read_avail = &ad7380_read_avail, + .write_raw = &ad7380_write_raw, + .get_current_scan_type = &ad7380_get_current_scan_type, + .debugfs_reg_access = &ad7380_debugfs_reg_access, +}; + +static int ad7380_init(struct ad7380_state *st, struct regulator *vref) +{ + int ret; + + /* perform hard reset */ + ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG2, + AD7380_CONFIG2_RESET, + FIELD_PREP(AD7380_CONFIG2_RESET, + AD7380_CONFIG2_RESET_HARD)); + if (ret < 0) + return ret; + + /* select internal or external reference voltage */ + ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG1, + AD7380_CONFIG1_REFSEL, + FIELD_PREP(AD7380_CONFIG1_REFSEL, + vref ? 1 : 0)); + if (ret < 0) + return ret; + + /* This is the default value after reset. */ + st->oversampling_ratio = 1; + + /* SPI 1-wire mode */ + return regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG2, + AD7380_CONFIG2_SDO, + FIELD_PREP(AD7380_CONFIG2_SDO, 1)); +} + +static void ad7380_regulator_disable(void *p) +{ + regulator_disable(p); +} + +static int ad7380_probe(struct spi_device *spi) +{ + struct iio_dev *indio_dev; + struct ad7380_state *st; + struct regulator *vref; + int ret, i; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi = spi; + st->chip_info = spi_get_device_match_data(spi); + if (!st->chip_info) + return dev_err_probe(&spi->dev, -EINVAL, "missing match data\n"); + + vref = devm_regulator_get_optional(&spi->dev, "refio"); + if (IS_ERR(vref)) { + if (PTR_ERR(vref) != -ENODEV) + return dev_err_probe(&spi->dev, PTR_ERR(vref), + "Failed to get refio regulator\n"); + + vref = NULL; + } + + /* + * If there is no REFIO supply, then it means that we are using + * the internal 2.5V reference, otherwise REFIO is reference voltage. + */ + if (vref) { + ret = regulator_enable(vref); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&spi->dev, + ad7380_regulator_disable, vref); + if (ret) + return ret; + + ret = regulator_get_voltage(vref); + if (ret < 0) + return ret; + + st->vref_mv = ret / 1000; + } else { + st->vref_mv = AD7380_INTERNAL_REF_MV; + } + + if (st->chip_info->num_vcm_supplies > ARRAY_SIZE(st->vcm_mv)) + return dev_err_probe(&spi->dev, -EINVAL, + "invalid number of VCM supplies\n"); + + /* + * pseudo-differential chips have common mode supplies for the negative + * input pin. + */ + for (i = 0; i < st->chip_info->num_vcm_supplies; i++) { + struct regulator *vcm; + + vcm = devm_regulator_get(&spi->dev, + st->chip_info->vcm_supplies[i]); + if (IS_ERR(vcm)) + return dev_err_probe(&spi->dev, PTR_ERR(vcm), + "Failed to get %s regulator\n", + st->chip_info->vcm_supplies[i]); + + ret = regulator_enable(vcm); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&spi->dev, + ad7380_regulator_disable, vcm); + if (ret) + return ret; + + ret = regulator_get_voltage(vcm); + if (ret < 0) + return ret; + + st->vcm_mv[i] = ret / 1000; + } + + st->regmap = devm_regmap_init(&spi->dev, NULL, st, &ad7380_regmap_config); + if (IS_ERR(st->regmap)) + return dev_err_probe(&spi->dev, PTR_ERR(st->regmap), + "failed to allocate register map\n"); + + /* + * Setting up a low latency read for getting sample data. Used for both + * direct read an triggered buffer. Additional fields will be set up in + * ad7380_update_xfers() based on the current state of the driver at the + * time of the read. + */ + + /* toggle CS (no data xfer) to trigger a conversion */ + st->xfer[0].cs_change = 1; + st->xfer[0].cs_change_delay.value = st->chip_info->timing_specs->t_csh_ns; + st->xfer[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; + + /* then do a second xfer to read the data */ + st->xfer[1].rx_buf = st->scan_data; + + spi_message_init_with_transfers(&st->msg, st->xfer, ARRAY_SIZE(st->xfer)); + + indio_dev->channels = st->chip_info->channels; + indio_dev->num_channels = st->chip_info->num_channels; + indio_dev->name = st->chip_info->name; + indio_dev->info = &ad7380_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->available_scan_masks = st->chip_info->available_scan_masks; + + ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, + iio_pollfunc_store_time, + ad7380_trigger_handler, + &ad7380_buffer_setup_ops); + if (ret) + return ret; + + ret = ad7380_init(st, vref); + if (ret) + return ret; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id ad7380_of_match_table[] = { + { .compatible = "adi,ad7380", .data = &ad7380_chip_info }, + { .compatible = "adi,ad7381", .data = &ad7381_chip_info }, + { .compatible = "adi,ad7383", .data = &ad7383_chip_info }, + { .compatible = "adi,ad7384", .data = &ad7384_chip_info }, + { .compatible = "adi,ad7380-4", .data = &ad7380_4_chip_info }, + { .compatible = "adi,ad7381-4", .data = &ad7381_4_chip_info }, + { .compatible = "adi,ad7383-4", .data = &ad7383_4_chip_info }, + { .compatible = "adi,ad7384-4", .data = &ad7384_4_chip_info }, + { } +}; + +static const struct spi_device_id ad7380_id_table[] = { + { "ad7380", (kernel_ulong_t)&ad7380_chip_info }, + { "ad7381", (kernel_ulong_t)&ad7381_chip_info }, + { "ad7383", (kernel_ulong_t)&ad7383_chip_info }, + { "ad7384", (kernel_ulong_t)&ad7384_chip_info }, + { "ad7380-4", (kernel_ulong_t)&ad7380_4_chip_info }, + { "ad7381-4", (kernel_ulong_t)&ad7381_4_chip_info }, + { "ad7383-4", (kernel_ulong_t)&ad7383_4_chip_info }, + { "ad7384-4", (kernel_ulong_t)&ad7384_4_chip_info }, + { } +}; +MODULE_DEVICE_TABLE(spi, ad7380_id_table); + +static struct spi_driver ad7380_driver = { + .driver = { + .name = "ad7380", + .of_match_table = ad7380_of_match_table, + }, + .probe = ad7380_probe, + .id_table = ad7380_id_table, +}; +module_spi_driver(ad7380_driver); + +MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>"); +MODULE_DESCRIPTION("Analog Devices AD738x ADC driver"); +MODULE_LICENSE("GPL"); |