// 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 * ad7386/7/8 : https://www.analog.com/media/en/technical-documentation/data-sheets/AD7386-7387-7388.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 * ad7386/7/8-4 : https://www.analog.com/media/en/technical-documentation/data-sheets/ad7386-4-7387-4-7388-4.pdf */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX_NUM_CHANNELS 8 /* 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_CH BIT(11) #define AD7380_CONFIG1_SEQ BIT(10) #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; unsigned int num_simult_channels; bool has_mux; 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 12-bit unsigned chips. */ static const struct iio_scan_type ad7380_scan_type_12_u[] = { [AD7380_SCAN_TYPE_NORMAL] = { .sign = 'u', .realbits = 12, .storagebits = 16, .endianness = IIO_CPU, }, [AD7380_SCAN_TYPE_RESOLUTION_BOOST] = { .sign = 'u', .realbits = 14, .storagebits = 16, .endianness = IIO_CPU, }, }; /* Extended scan types for 14-bit signed chips. */ static const struct iio_scan_type ad7380_scan_type_14_s[] = { [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 14-bit unsigned chips. */ static const struct iio_scan_type ad7380_scan_type_14_u[] = { [AD7380_SCAN_TYPE_NORMAL] = { .sign = 'u', .realbits = 14, .storagebits = 16, .endianness = IIO_CPU, }, [AD7380_SCAN_TYPE_RESOLUTION_BOOST] = { .sign = 'u', .realbits = 16, .storagebits = 16, .endianness = IIO_CPU, }, }; /* Extended scan types for 16-bit signed_chips. */ static const struct iio_scan_type ad7380_scan_type_16_s[] = { [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, }, }; /* Extended scan types for 16-bit unsigned chips. */ static const struct iio_scan_type ad7380_scan_type_16_u[] = { [AD7380_SCAN_TYPE_NORMAL] = { .sign = 'u', .realbits = 16, .storagebits = 16, .endianness = IIO_CPU, }, [AD7380_SCAN_TYPE_RESOLUTION_BOOST] = { .sign = 'u', .realbits = 18, .storagebits = 32, .endianness = IIO_CPU, }, }; #define AD7380_CHANNEL(index, bits, diff, sign) { \ .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##_##sign, \ .num_ext_scan_type = ARRAY_SIZE(ad7380_scan_type_##bits##_##sign), \ } #define DEFINE_AD7380_2_CHANNEL(name, bits, diff, sign) \ static const struct iio_chan_spec name[] = { \ AD7380_CHANNEL(0, bits, diff, sign), \ AD7380_CHANNEL(1, bits, diff, sign), \ IIO_CHAN_SOFT_TIMESTAMP(2), \ } #define DEFINE_AD7380_4_CHANNEL(name, bits, diff, sign) \ static const struct iio_chan_spec name[] = { \ AD7380_CHANNEL(0, bits, diff, sign), \ AD7380_CHANNEL(1, bits, diff, sign), \ AD7380_CHANNEL(2, bits, diff, sign), \ AD7380_CHANNEL(3, bits, diff, sign), \ IIO_CHAN_SOFT_TIMESTAMP(4), \ } #define DEFINE_AD7380_8_CHANNEL(name, bits, diff, sign) \ static const struct iio_chan_spec name[] = { \ AD7380_CHANNEL(0, bits, diff, sign), \ AD7380_CHANNEL(1, bits, diff, sign), \ AD7380_CHANNEL(2, bits, diff, sign), \ AD7380_CHANNEL(3, bits, diff, sign), \ AD7380_CHANNEL(4, bits, diff, sign), \ AD7380_CHANNEL(5, bits, diff, sign), \ AD7380_CHANNEL(6, bits, diff, sign), \ AD7380_CHANNEL(7, bits, diff, sign), \ IIO_CHAN_SOFT_TIMESTAMP(8), \ } /* fully differential */ DEFINE_AD7380_2_CHANNEL(ad7380_channels, 16, 1, s); DEFINE_AD7380_2_CHANNEL(ad7381_channels, 14, 1, s); DEFINE_AD7380_4_CHANNEL(ad7380_4_channels, 16, 1, s); DEFINE_AD7380_4_CHANNEL(ad7381_4_channels, 14, 1, s); /* pseudo differential */ DEFINE_AD7380_2_CHANNEL(ad7383_channels, 16, 0, s); DEFINE_AD7380_2_CHANNEL(ad7384_channels, 14, 0, s); DEFINE_AD7380_4_CHANNEL(ad7383_4_channels, 16, 0, s); DEFINE_AD7380_4_CHANNEL(ad7384_4_channels, 14, 0, s); /* Single ended */ DEFINE_AD7380_4_CHANNEL(ad7386_channels, 16, 0, u); DEFINE_AD7380_4_CHANNEL(ad7387_channels, 14, 0, u); DEFINE_AD7380_4_CHANNEL(ad7388_channels, 12, 0, u); DEFINE_AD7380_8_CHANNEL(ad7386_4_channels, 16, 0, u); DEFINE_AD7380_8_CHANNEL(ad7387_4_channels, 14, 0, u); DEFINE_AD7380_8_CHANNEL(ad7388_4_channels, 12, 0, u); 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 }; /* * Single ended parts have a 2:1 multiplexer in front of each ADC. * * From an IIO point of view, all inputs are exported, i.e ad7386/7/8 * export 4 channels and ad7386-4/7-4/8-4 export 8 channels. * * Inputs AinX0 of multiplexers correspond to the first half of IIO channels * (i.e 0-1 or 0-3) and inputs AinX1 correspond to second half (i.e 2-3 or * 4-7). Example for AD7386/7/8 (2 channels parts): * * IIO | AD7386/7/8 * | +---------------------------- * | | _____ ______ * | | | | | | * voltage0 | AinA0 --|--->| | | | * | | | mux |----->| ADCA |--- * voltage2 | AinA1 --|--->| | | | * | | |_____| |_____ | * | | _____ ______ * | | | | | | * voltage1 | AinB0 --|--->| | | | * | | | mux |----->| ADCB |--- * voltage3 | AinB1 --|--->| | | | * | | |_____| |______| * | | * | +---------------------------- * * Since this is simultaneous sampling for AinX0 OR AinX1 we have two separate * scan masks. * When sequencer mode is enabled, chip automatically cycles through * AinX0 and AinX1 channels. From an IIO point of view, we ca enable all * channels, at the cost of an extra read, thus dividing the maximum rate by * two. */ enum { AD7380_SCAN_MASK_CH_0, AD7380_SCAN_MASK_CH_1, AD7380_SCAN_MASK_SEQ, }; static const unsigned long ad7380_2x2_channel_scan_masks[] = { [AD7380_SCAN_MASK_CH_0] = GENMASK(1, 0), [AD7380_SCAN_MASK_CH_1] = GENMASK(3, 2), [AD7380_SCAN_MASK_SEQ] = GENMASK(3, 0), 0 }; static const unsigned long ad7380_2x4_channel_scan_masks[] = { [AD7380_SCAN_MASK_CH_0] = GENMASK(3, 0), [AD7380_SCAN_MASK_CH_1] = GENMASK(7, 4), [AD7380_SCAN_MASK_SEQ] = GENMASK(7, 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), .num_simult_channels = 2, .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), .num_simult_channels = 2, .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), .num_simult_channels = 2, .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), .num_simult_channels = 2, .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 ad7386_chip_info = { .name = "ad7386", .channels = ad7386_channels, .num_channels = ARRAY_SIZE(ad7386_channels), .num_simult_channels = 2, .has_mux = true, .available_scan_masks = ad7380_2x2_channel_scan_masks, .timing_specs = &ad7380_timing, }; static const struct ad7380_chip_info ad7387_chip_info = { .name = "ad7387", .channels = ad7387_channels, .num_channels = ARRAY_SIZE(ad7387_channels), .num_simult_channels = 2, .has_mux = true, .available_scan_masks = ad7380_2x2_channel_scan_masks, .timing_specs = &ad7380_timing, }; static const struct ad7380_chip_info ad7388_chip_info = { .name = "ad7388", .channels = ad7388_channels, .num_channels = ARRAY_SIZE(ad7388_channels), .num_simult_channels = 2, .has_mux = true, .available_scan_masks = ad7380_2x2_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), .num_simult_channels = 4, .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), .num_simult_channels = 4, .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), .num_simult_channels = 4, .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), .num_simult_channels = 4, .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 ad7386_4_chip_info = { .name = "ad7386-4", .channels = ad7386_4_channels, .num_channels = ARRAY_SIZE(ad7386_4_channels), .num_simult_channels = 4, .has_mux = true, .available_scan_masks = ad7380_2x4_channel_scan_masks, .timing_specs = &ad7380_4_timing, }; static const struct ad7380_chip_info ad7387_4_chip_info = { .name = "ad7387-4", .channels = ad7387_4_channels, .num_channels = ARRAY_SIZE(ad7387_4_channels), .num_simult_channels = 4, .has_mux = true, .available_scan_masks = ad7380_2x4_channel_scan_masks, .timing_specs = &ad7380_4_timing, }; static const struct ad7380_chip_info ad7388_4_chip_info = { .name = "ad7388-4", .channels = ad7388_4_channels, .num_channels = ARRAY_SIZE(ad7388_4_channels), .num_simult_channels = 4, .has_mux = true, .available_scan_masks = ad7380_2x4_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 ch; bool seq; unsigned int vref_mv; unsigned int vcm_mv[MAX_NUM_CHANNELS]; /* xfers, message an buffer for reading sample data */ struct spi_transfer normal_xfer[2]; struct spi_message normal_msg; struct spi_transfer seq_xfer[4]; struct spi_message seq_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(); } /* * When switching channel, the ADC require an additional settling time. * According to the datasheet, data is value on the third CS low. We already * have an extra toggle before each read (either direct reads or buffered reads) * to sample correct data, so we just add a single CS toggle at the end of the * register write. */ static int ad7380_set_ch(struct ad7380_state *st, unsigned int ch) { struct spi_transfer xfer = { .delay = { .value = T_CONVERT_NS, .unit = SPI_DELAY_UNIT_NSECS, } }; int ret; if (st->ch == ch) return 0; ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG1, AD7380_CONFIG1_CH, FIELD_PREP(AD7380_CONFIG1_CH, ch)); if (ret) return ret; st->ch = ch; if (st->oversampling_ratio > 1) xfer.delay.value = T_CONVERT_0_NS + T_CONVERT_X_NS * (st->oversampling_ratio - 1); return spi_sync_transfer(st->spi, &xfer, 1); } /** * 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) { struct spi_transfer *xfer = st->seq ? st->seq_xfer : st->normal_xfer; unsigned int t_convert = T_CONVERT_NS; /* * In the case of oversampling, conversion time is higher than in normal * mode. 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) t_convert = T_CONVERT_0_NS + T_CONVERT_X_NS * (st->oversampling_ratio - 1); if (st->seq) { xfer[0].delay.value = xfer[1].delay.value = t_convert; xfer[0].delay.unit = xfer[1].delay.unit = SPI_DELAY_UNIT_NSECS; xfer[2].bits_per_word = xfer[3].bits_per_word = scan_type->realbits; xfer[2].len = xfer[3].len = BITS_TO_BYTES(scan_type->storagebits) * st->chip_info->num_simult_channels; xfer[3].rx_buf = xfer[2].rx_buf + xfer[2].len; /* Additional delay required here when oversampling is enabled */ if (st->oversampling_ratio > 1) xfer[2].delay.value = t_convert; else xfer[2].delay.value = 0; xfer[2].delay.unit = SPI_DELAY_UNIT_NSECS; } else { xfer[0].delay.value = t_convert; xfer[0].delay.unit = SPI_DELAY_UNIT_NSECS; xfer[1].bits_per_word = scan_type->realbits; xfer[1].len = BITS_TO_BYTES(scan_type->storagebits) * st->chip_info->num_simult_channels; } } 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; struct spi_message *msg = &st->normal_msg; /* * 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); if (st->chip_info->has_mux) { unsigned int index; int ret; /* * Depending on the requested scan_mask and current state, * we need to either change CH bit, or enable sequencer mode * to sample correct data. * Sequencer mode is enabled if active mask corresponds to all * IIO channels enabled. Otherwise, CH bit is set. */ ret = iio_active_scan_mask_index(indio_dev); if (ret < 0) return ret; index = ret; if (index == AD7380_SCAN_MASK_SEQ) { ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG1, AD7380_CONFIG1_SEQ, FIELD_PREP(AD7380_CONFIG1_SEQ, 1)); if (ret) return ret; msg = &st->seq_msg; st->seq = true; } else { ret = ad7380_set_ch(st, index); if (ret) return ret; } } ad7380_update_xfers(st, scan_type); return spi_optimize_message(st->spi, msg); } static int ad7380_triggered_buffer_postdisable(struct iio_dev *indio_dev) { struct ad7380_state *st = iio_priv(indio_dev); struct spi_message *msg = &st->normal_msg; int ret; if (st->seq) { ret = regmap_update_bits(st->regmap, AD7380_REG_ADDR_CONFIG1, AD7380_CONFIG1_SEQ, FIELD_PREP(AD7380_CONFIG1_SEQ, 0)); if (ret) return ret; msg = &st->seq_msg; st->seq = false; } spi_unoptimize_message(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); struct spi_message *msg = st->seq ? &st->seq_msg : &st->normal_msg; int ret; ret = spi_sync(st->spi, 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) { unsigned int index = scan_index; int ret; if (st->chip_info->has_mux) { unsigned int ch = 0; if (index >= st->chip_info->num_simult_channels) { index -= st->chip_info->num_simult_channels; ch = 1; } ret = ad7380_set_ch(st, ch); if (ret) return ret; } ad7380_update_xfers(st, scan_type); ret = spi_sync(st->spi, &st->normal_msg); if (ret < 0) return ret; if (scan_type->storagebits > 16) { if (scan_type->sign == 's') *val = sign_extend32(*(u32 *)(st->scan_data + 4 * index), scan_type->realbits - 1); else *val = *(u32 *)(st->scan_data + 4 * index) & GENMASK(scan_type->realbits - 1, 0); } else { if (scan_type->sign == 's') *val = sign_extend32(*(u16 *)(st->scan_data + 2 * index), scan_type->realbits - 1); else *val = *(u16 *)(st->scan_data + 2 * index) & GENMASK(scan_type->realbits - 1, 0); } 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; st->ch = 0; st->seq = false; /* 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 xfer structures for both normal and sequence mode. These * struct are used for both direct read and 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. */ /* * In normal mode a read is composed of two steps: * - first, toggle CS (no data xfer) to trigger a conversion * - then, read data */ st->normal_xfer[0].cs_change = 1; st->normal_xfer[0].cs_change_delay.value = st->chip_info->timing_specs->t_csh_ns; st->normal_xfer[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; st->normal_xfer[1].rx_buf = st->scan_data; spi_message_init_with_transfers(&st->normal_msg, st->normal_xfer, ARRAY_SIZE(st->normal_xfer)); /* * In sequencer mode a read is composed of four steps: * - CS toggle (no data xfer) to get the right point in the sequence * - CS toggle (no data xfer) to trigger a conversion of AinX0 and * acquisition of AinX1 * - 2 data reads, to read AinX0 and AinX1 */ st->seq_xfer[0].cs_change = 1; st->seq_xfer[0].cs_change_delay.value = st->chip_info->timing_specs->t_csh_ns; st->seq_xfer[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; st->seq_xfer[1].cs_change = 1; st->seq_xfer[1].cs_change_delay.value = st->chip_info->timing_specs->t_csh_ns; st->seq_xfer[1].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; st->seq_xfer[2].rx_buf = st->scan_data; st->seq_xfer[2].cs_change = 1; st->seq_xfer[2].cs_change_delay.value = st->chip_info->timing_specs->t_csh_ns; st->seq_xfer[2].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; spi_message_init_with_transfers(&st->seq_msg, st->seq_xfer, ARRAY_SIZE(st->seq_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,ad7386", .data = &ad7386_chip_info }, { .compatible = "adi,ad7387", .data = &ad7387_chip_info }, { .compatible = "adi,ad7388", .data = &ad7388_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 }, { .compatible = "adi,ad7386-4", .data = &ad7386_4_chip_info }, { .compatible = "adi,ad7387-4", .data = &ad7387_4_chip_info }, { .compatible = "adi,ad7388-4", .data = &ad7388_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 }, { "ad7386", (kernel_ulong_t)&ad7386_chip_info }, { "ad7387", (kernel_ulong_t)&ad7387_chip_info }, { "ad7388", (kernel_ulong_t)&ad7388_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 }, { "ad7386-4", (kernel_ulong_t)&ad7386_4_chip_info }, { "ad7387-4", (kernel_ulong_t)&ad7387_4_chip_info }, { "ad7388-4", (kernel_ulong_t)&ad7388_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 "); MODULE_DESCRIPTION("Analog Devices AD738x ADC driver"); MODULE_LICENSE("GPL");