// SPDX-License-Identifier: GPL-2.0 /* TI ADS1298 chip family driver * Copyright (C) 2023 - 2024 Topic Embedded Products */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Commands */ #define ADS1298_CMD_WAKEUP 0x02 #define ADS1298_CMD_STANDBY 0x04 #define ADS1298_CMD_RESET 0x06 #define ADS1298_CMD_START 0x08 #define ADS1298_CMD_STOP 0x0a #define ADS1298_CMD_RDATAC 0x10 #define ADS1298_CMD_SDATAC 0x11 #define ADS1298_CMD_RDATA 0x12 #define ADS1298_CMD_RREG 0x20 #define ADS1298_CMD_WREG 0x40 /* Registers */ #define ADS1298_REG_ID 0x00 #define ADS1298_MASK_ID_FAMILY GENMASK(7, 3) #define ADS1298_MASK_ID_CHANNELS GENMASK(2, 0) #define ADS1298_ID_FAMILY_ADS129X 0x90 #define ADS1298_ID_FAMILY_ADS129XR 0xd0 #define ADS1298_REG_CONFIG1 0x01 #define ADS1298_MASK_CONFIG1_HR BIT(7) #define ADS1298_MASK_CONFIG1_DR GENMASK(2, 0) #define ADS1298_SHIFT_DR_HR 6 #define ADS1298_SHIFT_DR_LP 7 #define ADS1298_LOWEST_DR 0x06 #define ADS1298_REG_CONFIG2 0x02 #define ADS1298_MASK_CONFIG2_RESERVED BIT(6) #define ADS1298_MASK_CONFIG2_WCT_CHOP BIT(5) #define ADS1298_MASK_CONFIG2_INT_TEST BIT(4) #define ADS1298_MASK_CONFIG2_TEST_AMP BIT(2) #define ADS1298_MASK_CONFIG2_TEST_FREQ_DC GENMASK(1, 0) #define ADS1298_MASK_CONFIG2_TEST_FREQ_SLOW 0 #define ADS1298_MASK_CONFIG2_TEST_FREQ_FAST BIT(0) #define ADS1298_REG_CONFIG3 0x03 #define ADS1298_MASK_CONFIG3_PWR_REFBUF BIT(7) #define ADS1298_MASK_CONFIG3_RESERVED BIT(6) #define ADS1298_MASK_CONFIG3_VREF_4V BIT(5) #define ADS1298_REG_LOFF 0x04 #define ADS1298_REG_CHnSET(n) (0x05 + n) #define ADS1298_MASK_CH_PD BIT(7) #define ADS1298_MASK_CH_PGA GENMASK(6, 4) #define ADS1298_MASK_CH_MUX GENMASK(2, 0) #define ADS1298_REG_LOFF_STATP 0x12 #define ADS1298_REG_LOFF_STATN 0x13 #define ADS1298_REG_CONFIG4 0x17 #define ADS1298_MASK_CONFIG4_SINGLE_SHOT BIT(3) #define ADS1298_REG_WCT1 0x18 #define ADS1298_REG_WCT2 0x19 #define ADS1298_MAX_CHANNELS 8 #define ADS1298_BITS_PER_SAMPLE 24 #define ADS1298_CLK_RATE_HZ 2048000 #define ADS1298_CLOCKS_TO_USECS(x) \ (DIV_ROUND_UP((x) * MICROHZ_PER_HZ, ADS1298_CLK_RATE_HZ)) /* * Read/write register commands require 4 clocks to decode, for speeds above * 2x the clock rate, this would require extra time between the command byte and * the data. Much simpler is to just limit the SPI transfer speed while doing * register access. */ #define ADS1298_SPI_BUS_SPEED_SLOW ADS1298_CLK_RATE_HZ /* For reading and writing registers, we need a 3-byte buffer */ #define ADS1298_SPI_CMD_BUFFER_SIZE 3 /* Outputs status word and 'n' 24-bit samples, plus the command byte */ #define ADS1298_SPI_RDATA_BUFFER_SIZE(n) (((n) + 1) * 3 + 1) #define ADS1298_SPI_RDATA_BUFFER_SIZE_MAX \ ADS1298_SPI_RDATA_BUFFER_SIZE(ADS1298_MAX_CHANNELS) struct ads1298_private { const struct ads1298_chip_info *chip_info; struct spi_device *spi; struct regulator *reg_avdd; struct regulator *reg_vref; struct clk *clk; struct regmap *regmap; struct completion completion; struct iio_trigger *trig; struct spi_transfer rdata_xfer; struct spi_message rdata_msg; spinlock_t irq_busy_lock; /* Handshake between SPI and DRDY irqs */ /* * rdata_xfer_busy increments when a DRDY occurs and decrements when SPI * completion is reported. Hence its meaning is: * 0 = Waiting for DRDY interrupt * 1 = SPI transfer in progress * 2 = DRDY during SPI transfer, start another transfer on completion * >2 = Multiple DRDY during transfer, lost rdata_xfer_busy - 2 samples */ unsigned int rdata_xfer_busy; /* Temporary storage for demuxing data after SPI transfer */ u32 bounce_buffer[ADS1298_MAX_CHANNELS]; /* For synchronous SPI exchanges (read/write registers) */ u8 cmd_buffer[ADS1298_SPI_CMD_BUFFER_SIZE] __aligned(IIO_DMA_MINALIGN); /* Buffer used for incoming SPI data */ u8 rx_buffer[ADS1298_SPI_RDATA_BUFFER_SIZE_MAX]; /* Contains the RDATA command and zeroes to clock out */ u8 tx_buffer[ADS1298_SPI_RDATA_BUFFER_SIZE_MAX]; }; /* Three bytes per sample in RX buffer, starting at offset 4 */ #define ADS1298_OFFSET_IN_RX_BUFFER(index) (3 * (index) + 4) #define ADS1298_CHAN(index) \ { \ .type = IIO_VOLTAGE, \ .indexed = 1, \ .channel = index, \ .address = ADS1298_OFFSET_IN_RX_BUFFER(index), \ .info_mask_separate = \ BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_SCALE), \ .info_mask_shared_by_all = \ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .scan_index = index, \ .scan_type = { \ .sign = 's', \ .realbits = ADS1298_BITS_PER_SAMPLE, \ .storagebits = 32, \ .endianness = IIO_CPU, \ }, \ } static const struct iio_chan_spec ads1298_channels[] = { ADS1298_CHAN(0), ADS1298_CHAN(1), ADS1298_CHAN(2), ADS1298_CHAN(3), ADS1298_CHAN(4), ADS1298_CHAN(5), ADS1298_CHAN(6), ADS1298_CHAN(7), }; static int ads1298_write_cmd(struct ads1298_private *priv, u8 command) { struct spi_transfer xfer = { .tx_buf = priv->cmd_buffer, .rx_buf = priv->cmd_buffer, .len = 1, .speed_hz = ADS1298_SPI_BUS_SPEED_SLOW, .delay = { .value = 2, .unit = SPI_DELAY_UNIT_USECS, }, }; priv->cmd_buffer[0] = command; return spi_sync_transfer(priv->spi, &xfer, 1); } static int ads1298_read_one(struct ads1298_private *priv, int chan_index) { int ret; /* Enable the channel */ ret = regmap_update_bits(priv->regmap, ADS1298_REG_CHnSET(chan_index), ADS1298_MASK_CH_PD, 0); if (ret) return ret; /* Enable single-shot mode, so we don't need to send a STOP */ ret = regmap_update_bits(priv->regmap, ADS1298_REG_CONFIG4, ADS1298_MASK_CONFIG4_SINGLE_SHOT, ADS1298_MASK_CONFIG4_SINGLE_SHOT); if (ret) return ret; reinit_completion(&priv->completion); ret = ads1298_write_cmd(priv, ADS1298_CMD_START); if (ret < 0) { dev_err(&priv->spi->dev, "CMD_START error: %d\n", ret); return ret; } /* Cannot take longer than 40ms (250Hz) */ ret = wait_for_completion_timeout(&priv->completion, msecs_to_jiffies(50)); if (!ret) return -ETIMEDOUT; return 0; } static int ads1298_get_samp_freq(struct ads1298_private *priv, int *val) { unsigned long rate; unsigned int cfg; int ret; ret = regmap_read(priv->regmap, ADS1298_REG_CONFIG1, &cfg); if (ret) return ret; if (priv->clk) rate = clk_get_rate(priv->clk); else rate = ADS1298_CLK_RATE_HZ; if (!rate) return -EINVAL; /* Data rate shift depends on HR/LP mode */ if (cfg & ADS1298_MASK_CONFIG1_HR) rate >>= ADS1298_SHIFT_DR_HR; else rate >>= ADS1298_SHIFT_DR_LP; *val = rate >> (cfg & ADS1298_MASK_CONFIG1_DR); return IIO_VAL_INT; } static int ads1298_set_samp_freq(struct ads1298_private *priv, int val) { unsigned long rate; unsigned int factor; unsigned int cfg; if (priv->clk) rate = clk_get_rate(priv->clk); else rate = ADS1298_CLK_RATE_HZ; if (!rate) return -EINVAL; if (val <= 0) return -EINVAL; factor = (rate >> ADS1298_SHIFT_DR_HR) / val; if (factor >= BIT(ADS1298_SHIFT_DR_LP)) cfg = ADS1298_LOWEST_DR; else if (factor) cfg = ADS1298_MASK_CONFIG1_HR | ilog2(factor); /* Use HR mode */ else cfg = ADS1298_MASK_CONFIG1_HR; /* Fastest possible */ return regmap_update_bits(priv->regmap, ADS1298_REG_CONFIG1, ADS1298_MASK_CONFIG1_HR | ADS1298_MASK_CONFIG1_DR, cfg); } static const u8 ads1298_pga_settings[] = { 6, 1, 2, 3, 4, 8, 12 }; static int ads1298_get_scale(struct ads1298_private *priv, int channel, int *val, int *val2) { int ret; unsigned int regval; u8 gain; if (priv->reg_vref) { ret = regulator_get_voltage(priv->reg_vref); if (ret < 0) return ret; *val = ret / MILLI; /* Convert to millivolts */ } else { ret = regmap_read(priv->regmap, ADS1298_REG_CONFIG3, ®val); if (ret) return ret; /* Reference in millivolts */ *val = regval & ADS1298_MASK_CONFIG3_VREF_4V ? 4000 : 2400; } ret = regmap_read(priv->regmap, ADS1298_REG_CHnSET(channel), ®val); if (ret) return ret; gain = ads1298_pga_settings[FIELD_GET(ADS1298_MASK_CH_PGA, regval)]; *val /= gain; /* Full scale is VREF / gain */ *val2 = ADS1298_BITS_PER_SAMPLE - 1; /* Signed, hence the -1 */ return IIO_VAL_FRACTIONAL_LOG2; } static int ads1298_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct ads1298_private *priv = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; ret = ads1298_read_one(priv, chan->scan_index); iio_device_release_direct_mode(indio_dev); if (ret) return ret; *val = sign_extend32(get_unaligned_be24(priv->rx_buffer + chan->address), ADS1298_BITS_PER_SAMPLE - 1); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: return ads1298_get_scale(priv, chan->channel, val, val2); case IIO_CHAN_INFO_SAMP_FREQ: return ads1298_get_samp_freq(priv, val); case IIO_CHAN_INFO_OVERSAMPLING_RATIO: ret = regmap_read(priv->regmap, ADS1298_REG_CONFIG1, val); if (ret) return ret; *val = 16 << (*val & ADS1298_MASK_CONFIG1_DR); return IIO_VAL_INT; default: return -EINVAL; } } static int ads1298_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct ads1298_private *priv = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: return ads1298_set_samp_freq(priv, val); default: return -EINVAL; } } static int ads1298_reg_write(void *context, unsigned int reg, unsigned int val) { struct ads1298_private *priv = context; struct spi_transfer reg_write_xfer = { .tx_buf = priv->cmd_buffer, .rx_buf = priv->cmd_buffer, .len = 3, .speed_hz = ADS1298_SPI_BUS_SPEED_SLOW, .delay = { .value = 2, .unit = SPI_DELAY_UNIT_USECS, }, }; priv->cmd_buffer[0] = ADS1298_CMD_WREG | reg; priv->cmd_buffer[1] = 0; /* Number of registers to be written - 1 */ priv->cmd_buffer[2] = val; return spi_sync_transfer(priv->spi, ®_write_xfer, 1); } static int ads1298_reg_read(void *context, unsigned int reg, unsigned int *val) { struct ads1298_private *priv = context; struct spi_transfer reg_read_xfer = { .tx_buf = priv->cmd_buffer, .rx_buf = priv->cmd_buffer, .len = 3, .speed_hz = ADS1298_SPI_BUS_SPEED_SLOW, .delay = { .value = 2, .unit = SPI_DELAY_UNIT_USECS, }, }; int ret; priv->cmd_buffer[0] = ADS1298_CMD_RREG | reg; priv->cmd_buffer[1] = 0; /* Number of registers to be read - 1 */ priv->cmd_buffer[2] = 0; ret = spi_sync_transfer(priv->spi, ®_read_xfer, 1); if (ret) return ret; *val = priv->cmd_buffer[2]; return 0; } static int ads1298_reg_access(struct iio_dev *indio_dev, unsigned int reg, unsigned int writeval, unsigned int *readval) { struct ads1298_private *priv = iio_priv(indio_dev); if (readval) return regmap_read(priv->regmap, reg, readval); return regmap_write(priv->regmap, reg, writeval); } static void ads1298_rdata_unmark_busy(struct ads1298_private *priv) { /* Notify we're no longer waiting for the SPI transfer to complete */ guard(spinlock_irqsave)(&priv->irq_busy_lock); priv->rdata_xfer_busy = 0; } static int ads1298_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct ads1298_private *priv = iio_priv(indio_dev); unsigned int val; int ret; int i; /* Make the interrupt routines start with a clean slate */ ads1298_rdata_unmark_busy(priv); /* Configure power-down bits to match scan mask */ for (i = 0; i < indio_dev->num_channels; i++) { val = test_bit(i, scan_mask) ? 0 : ADS1298_MASK_CH_PD; ret = regmap_update_bits(priv->regmap, ADS1298_REG_CHnSET(i), ADS1298_MASK_CH_PD, val); if (ret) return ret; } return 0; } static const struct iio_info ads1298_info = { .read_raw = &ads1298_read_raw, .write_raw = &ads1298_write_raw, .update_scan_mode = &ads1298_update_scan_mode, .debugfs_reg_access = &ads1298_reg_access, }; static void ads1298_rdata_release_busy_or_restart(struct ads1298_private *priv) { guard(spinlock_irqsave)(&priv->irq_busy_lock); if (priv->rdata_xfer_busy > 1) { /* * DRDY interrupt occurred before SPI completion. Start a new * SPI transaction now to retrieve the data that wasn't latched * into the ADS1298 chip's transfer buffer yet. */ spi_async(priv->spi, &priv->rdata_msg); /* * If more than one DRDY took place, there was an overrun. Since * the sample is already lost, reset the counter to 1 so that * we will wait for a DRDY interrupt after this SPI transaction. */ priv->rdata_xfer_busy = 1; } else { /* No pending data, wait for DRDY */ priv->rdata_xfer_busy = 0; } } /* Called from SPI completion interrupt handler */ static void ads1298_rdata_complete(void *context) { struct iio_dev *indio_dev = context; struct ads1298_private *priv = iio_priv(indio_dev); int scan_index; u32 *bounce = priv->bounce_buffer; if (!iio_buffer_enabled(indio_dev)) { /* * for a single transfer mode we're kept in direct_mode until * completion, avoiding a race with buffered IO. */ ads1298_rdata_unmark_busy(priv); complete(&priv->completion); return; } /* Demux the channel data into our bounce buffer */ iio_for_each_active_channel(indio_dev, scan_index) { const struct iio_chan_spec *scan_chan = &indio_dev->channels[scan_index]; const u8 *data = priv->rx_buffer + scan_chan->address; *bounce++ = get_unaligned_be24(data); } /* rx_buffer can be overwritten from this point on */ ads1298_rdata_release_busy_or_restart(priv); iio_push_to_buffers(indio_dev, priv->bounce_buffer); } static irqreturn_t ads1298_interrupt(int irq, void *dev_id) { struct iio_dev *indio_dev = dev_id; struct ads1298_private *priv = iio_priv(indio_dev); unsigned int wasbusy; guard(spinlock_irqsave)(&priv->irq_busy_lock); wasbusy = priv->rdata_xfer_busy++; /* When no SPI transfer in transit, start one now */ if (!wasbusy) spi_async(priv->spi, &priv->rdata_msg); return IRQ_HANDLED; }; static int ads1298_buffer_postenable(struct iio_dev *indio_dev) { struct ads1298_private *priv = iio_priv(indio_dev); int ret; /* Disable single-shot mode */ ret = regmap_update_bits(priv->regmap, ADS1298_REG_CONFIG4, ADS1298_MASK_CONFIG4_SINGLE_SHOT, 0); if (ret) return ret; return ads1298_write_cmd(priv, ADS1298_CMD_START); } static int ads1298_buffer_predisable(struct iio_dev *indio_dev) { struct ads1298_private *priv = iio_priv(indio_dev); return ads1298_write_cmd(priv, ADS1298_CMD_STOP); } static const struct iio_buffer_setup_ops ads1298_setup_ops = { .postenable = &ads1298_buffer_postenable, .predisable = &ads1298_buffer_predisable, }; static void ads1298_reg_disable(void *reg) { regulator_disable(reg); } static const struct regmap_range ads1298_regmap_volatile_range[] = { regmap_reg_range(ADS1298_REG_LOFF_STATP, ADS1298_REG_LOFF_STATN), }; static const struct regmap_access_table ads1298_regmap_volatile = { .yes_ranges = ads1298_regmap_volatile_range, .n_yes_ranges = ARRAY_SIZE(ads1298_regmap_volatile_range), }; static const struct regmap_config ads1298_regmap_config = { .reg_bits = 8, .val_bits = 8, .reg_read = ads1298_reg_read, .reg_write = ads1298_reg_write, .max_register = ADS1298_REG_WCT2, .volatile_table = &ads1298_regmap_volatile, .cache_type = REGCACHE_MAPLE, }; static int ads1298_init(struct iio_dev *indio_dev) { struct ads1298_private *priv = iio_priv(indio_dev); struct device *dev = &priv->spi->dev; const char *suffix; unsigned int val; int ret; /* Device initializes into RDATAC mode, which we don't want */ ret = ads1298_write_cmd(priv, ADS1298_CMD_SDATAC); if (ret) return ret; ret = regmap_read(priv->regmap, ADS1298_REG_ID, &val); if (ret) return ret; /* Fill in name and channel count based on what the chip told us */ indio_dev->num_channels = 4 + 2 * (val & ADS1298_MASK_ID_CHANNELS); switch (val & ADS1298_MASK_ID_FAMILY) { case ADS1298_ID_FAMILY_ADS129X: suffix = ""; break; case ADS1298_ID_FAMILY_ADS129XR: suffix = "r"; break; default: return dev_err_probe(dev, -ENODEV, "Unknown ID: 0x%x\n", val); } indio_dev->name = devm_kasprintf(dev, GFP_KERNEL, "ads129%u%s", indio_dev->num_channels, suffix); /* Enable internal test signal, double amplitude, double frequency */ ret = regmap_write(priv->regmap, ADS1298_REG_CONFIG2, ADS1298_MASK_CONFIG2_RESERVED | ADS1298_MASK_CONFIG2_INT_TEST | ADS1298_MASK_CONFIG2_TEST_AMP | ADS1298_MASK_CONFIG2_TEST_FREQ_FAST); if (ret) return ret; val = ADS1298_MASK_CONFIG3_RESERVED; /* Must write 1 always */ if (!priv->reg_vref) { /* Enable internal reference */ val |= ADS1298_MASK_CONFIG3_PWR_REFBUF; /* Use 4V VREF when power supply is at least 4.4V */ if (regulator_get_voltage(priv->reg_avdd) >= 4400000) val |= ADS1298_MASK_CONFIG3_VREF_4V; } return regmap_write(priv->regmap, ADS1298_REG_CONFIG3, val); } static int ads1298_probe(struct spi_device *spi) { struct ads1298_private *priv; struct iio_dev *indio_dev; struct device *dev = &spi->dev; struct gpio_desc *reset_gpio; int ret; indio_dev = devm_iio_device_alloc(dev, sizeof(*priv)); if (!indio_dev) return -ENOMEM; priv = iio_priv(indio_dev); /* Reset to be asserted before enabling clock and power */ reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(reset_gpio)) return dev_err_probe(dev, PTR_ERR(reset_gpio), "Cannot get reset GPIO\n"); /* VREF can be supplied externally, otherwise use internal reference */ priv->reg_vref = devm_regulator_get_optional(dev, "vref"); if (IS_ERR(priv->reg_vref)) { if (PTR_ERR(priv->reg_vref) != -ENODEV) return dev_err_probe(dev, PTR_ERR(priv->reg_vref), "Failed to get vref regulator\n"); priv->reg_vref = NULL; } else { ret = regulator_enable(priv->reg_vref); if (ret) return ret; ret = devm_add_action_or_reset(dev, ads1298_reg_disable, priv->reg_vref); if (ret) return ret; } priv->clk = devm_clk_get_optional_enabled(dev, "clk"); if (IS_ERR(priv->clk)) return dev_err_probe(dev, PTR_ERR(priv->clk), "Failed to get clk\n"); priv->reg_avdd = devm_regulator_get(dev, "avdd"); if (IS_ERR(priv->reg_avdd)) return dev_err_probe(dev, PTR_ERR(priv->reg_avdd), "Failed to get avdd regulator\n"); ret = regulator_enable(priv->reg_avdd); if (ret) return dev_err_probe(dev, ret, "Failed to enable avdd regulator\n"); ret = devm_add_action_or_reset(dev, ads1298_reg_disable, priv->reg_avdd); if (ret) return ret; priv->spi = spi; init_completion(&priv->completion); spin_lock_init(&priv->irq_busy_lock); priv->regmap = devm_regmap_init(dev, NULL, priv, &ads1298_regmap_config); if (IS_ERR(priv->regmap)) return PTR_ERR(priv->regmap); indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE; indio_dev->channels = ads1298_channels; indio_dev->info = &ads1298_info; if (reset_gpio) { /* * Deassert reset now that clock and power are active. * Minimum reset pulsewidth is 2 clock cycles. */ fsleep(ADS1298_CLOCKS_TO_USECS(2)); gpiod_set_value_cansleep(reset_gpio, 0); } else { ret = ads1298_write_cmd(priv, ADS1298_CMD_RESET); if (ret) return dev_err_probe(dev, ret, "RESET failed\n"); } /* Wait 18 clock cycles for reset command to complete */ fsleep(ADS1298_CLOCKS_TO_USECS(18)); ret = ads1298_init(indio_dev); if (ret) return dev_err_probe(dev, ret, "Init failed\n"); priv->tx_buffer[0] = ADS1298_CMD_RDATA; priv->rdata_xfer.tx_buf = priv->tx_buffer; priv->rdata_xfer.rx_buf = priv->rx_buffer; priv->rdata_xfer.len = ADS1298_SPI_RDATA_BUFFER_SIZE(indio_dev->num_channels); /* Must keep CS low for 4 clocks */ priv->rdata_xfer.delay.value = 2; priv->rdata_xfer.delay.unit = SPI_DELAY_UNIT_USECS; spi_message_init_with_transfers(&priv->rdata_msg, &priv->rdata_xfer, 1); priv->rdata_msg.complete = &ads1298_rdata_complete; priv->rdata_msg.context = indio_dev; ret = devm_request_irq(dev, spi->irq, &ads1298_interrupt, IRQF_TRIGGER_FALLING, indio_dev->name, indio_dev); if (ret) return ret; ret = devm_iio_kfifo_buffer_setup(dev, indio_dev, &ads1298_setup_ops); if (ret) return ret; return devm_iio_device_register(dev, indio_dev); } static const struct spi_device_id ads1298_id[] = { { "ads1298" }, { } }; MODULE_DEVICE_TABLE(spi, ads1298_id); static const struct of_device_id ads1298_of_table[] = { { .compatible = "ti,ads1298" }, { } }; MODULE_DEVICE_TABLE(of, ads1298_of_table); static struct spi_driver ads1298_driver = { .driver = { .name = "ads1298", .of_match_table = ads1298_of_table, }, .probe = ads1298_probe, .id_table = ads1298_id, }; module_spi_driver(ads1298_driver); MODULE_AUTHOR("Mike Looijmans "); MODULE_DESCRIPTION("TI ADS1298 ADC"); MODULE_LICENSE("GPL");