| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Marcelo Schmitt | 1168 | 96.37% | 1 | 14.29% |
| David Lechner | 18 | 1.49% | 1 | 14.29% |
| Jonathan Cameron | 12 | 0.99% | 2 | 28.57% |
| Sergiu Cuciurean | 11 | 0.91% | 1 | 14.29% |
| Rob Herring | 2 | 0.17% | 1 | 14.29% |
| Guoqing Chi | 1 | 0.08% | 1 | 14.29% |
| Total | 1212 | 7 |
// SPDX-License-Identifier: GPL-2.0 /* * Analog Devices AD7292 SPI ADC driver * * Copyright 2019 Analog Devices Inc. */ #include <linux/bitfield.h> #include <linux/device.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/property.h> #include <linux/regulator/consumer.h> #include <linux/spi/spi.h> #include <linux/iio/iio.h> #define ADI_VENDOR_ID 0x0018 #define AD7292_INTERNAL_REF_MV 1250 /* AD7292 registers definition */ #define AD7292_REG_VENDOR_ID 0x00 #define AD7292_REG_CONF_BANK 0x05 #define AD7292_REG_CONV_COMM 0x0E #define AD7292_REG_ADC_CH(x) (0x10 + (x)) /* AD7292 configuration bank subregisters definition */ #define AD7292_BANK_REG_VIN_RNG0 0x10 #define AD7292_BANK_REG_VIN_RNG1 0x11 #define AD7292_BANK_REG_SAMP_MODE 0x12 #define AD7292_RD_FLAG_MSK(x) (BIT(7) | ((x) & 0x3F)) /* AD7292_REG_ADC_CONVERSION */ #define AD7292_ADC_DATA_MASK GENMASK(15, 6) #define AD7292_ADC_DATA(x) FIELD_GET(AD7292_ADC_DATA_MASK, x) /* AD7292_CHANNEL_SAMPLING_MODE */ #define AD7292_CH_SAMP_MODE(reg, ch) (((reg) >> 8) & BIT(ch)) /* AD7292_CHANNEL_VIN_RANGE */ #define AD7292_CH_VIN_RANGE(reg, ch) ((reg) & BIT(ch)) #define AD7292_VOLTAGE_CHAN(_chan) \ { \ .type = IIO_VOLTAGE, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_SCALE), \ .indexed = 1, \ .channel = _chan, \ } static const struct iio_chan_spec ad7292_channels[] = { AD7292_VOLTAGE_CHAN(0), AD7292_VOLTAGE_CHAN(1), AD7292_VOLTAGE_CHAN(2), AD7292_VOLTAGE_CHAN(3), AD7292_VOLTAGE_CHAN(4), AD7292_VOLTAGE_CHAN(5), AD7292_VOLTAGE_CHAN(6), AD7292_VOLTAGE_CHAN(7) }; static const struct iio_chan_spec ad7292_channels_diff[] = { { .type = IIO_VOLTAGE, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), .indexed = 1, .differential = 1, .channel = 0, .channel2 = 1, }, AD7292_VOLTAGE_CHAN(2), AD7292_VOLTAGE_CHAN(3), AD7292_VOLTAGE_CHAN(4), AD7292_VOLTAGE_CHAN(5), AD7292_VOLTAGE_CHAN(6), AD7292_VOLTAGE_CHAN(7) }; struct ad7292_state { struct spi_device *spi; unsigned short vref_mv; __be16 d16 __aligned(IIO_DMA_MINALIGN); u8 d8[2]; }; static int ad7292_spi_reg_read(struct ad7292_state *st, unsigned int addr) { int ret; st->d8[0] = AD7292_RD_FLAG_MSK(addr); ret = spi_write_then_read(st->spi, st->d8, 1, &st->d16, 2); if (ret < 0) return ret; return be16_to_cpu(st->d16); } static int ad7292_spi_subreg_read(struct ad7292_state *st, unsigned int addr, unsigned int sub_addr, unsigned int len) { unsigned int shift = 16 - (8 * len); int ret; st->d8[0] = AD7292_RD_FLAG_MSK(addr); st->d8[1] = sub_addr; ret = spi_write_then_read(st->spi, st->d8, 2, &st->d16, len); if (ret < 0) return ret; return (be16_to_cpu(st->d16) >> shift); } static int ad7292_single_conversion(struct ad7292_state *st, unsigned int chan_addr) { int ret; struct spi_transfer t[] = { { .tx_buf = &st->d8, .len = 4, .delay = { .value = 6, .unit = SPI_DELAY_UNIT_USECS }, }, { .rx_buf = &st->d16, .len = 2, }, }; st->d8[0] = chan_addr; st->d8[1] = AD7292_RD_FLAG_MSK(AD7292_REG_CONV_COMM); ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); if (ret < 0) return ret; return be16_to_cpu(st->d16); } static int ad7292_vin_range_multiplier(struct ad7292_state *st, int channel) { int samp_mode, range0, range1, factor = 1; /* * Every AD7292 ADC channel may have its input range adjusted according * to the settings at the ADC sampling mode and VIN range subregisters. * For a given channel, the minimum input range is equal to Vref, and it * may be increased by a multiplier factor of 2 or 4 according to the * following rule: * If channel is being sampled with respect to AGND: * factor = 4 if VIN range0 and VIN range1 equal 0 * factor = 2 if only one of VIN ranges equal 1 * factor = 1 if both VIN range0 and VIN range1 equal 1 * If channel is being sampled with respect to AVDD: * factor = 4 if VIN range0 and VIN range1 equal 0 * Behavior is undefined if any of VIN range doesn't equal 0 */ samp_mode = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK, AD7292_BANK_REG_SAMP_MODE, 2); if (samp_mode < 0) return samp_mode; range0 = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK, AD7292_BANK_REG_VIN_RNG0, 2); if (range0 < 0) return range0; range1 = ad7292_spi_subreg_read(st, AD7292_REG_CONF_BANK, AD7292_BANK_REG_VIN_RNG1, 2); if (range1 < 0) return range1; if (AD7292_CH_SAMP_MODE(samp_mode, channel)) { /* Sampling with respect to AGND */ if (!AD7292_CH_VIN_RANGE(range0, channel)) factor *= 2; if (!AD7292_CH_VIN_RANGE(range1, channel)) factor *= 2; } else { /* Sampling with respect to AVDD */ if (AD7292_CH_VIN_RANGE(range0, channel) || AD7292_CH_VIN_RANGE(range1, channel)) return -EPERM; factor = 4; } return factor; } static int ad7292_read_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, int *val, int *val2, long info) { struct ad7292_state *st = iio_priv(indio_dev); unsigned int ch_addr; int ret; switch (info) { case IIO_CHAN_INFO_RAW: ch_addr = AD7292_REG_ADC_CH(chan->channel); ret = ad7292_single_conversion(st, ch_addr); if (ret < 0) return ret; *val = AD7292_ADC_DATA(ret); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: /* * To convert a raw value to standard units, the IIO defines * this formula: Scaled value = (raw + offset) * scale. * For the scale to be a correct multiplier for (raw + offset), * it must be calculated as the input range divided by the * number of possible distinct input values. Given the ADC data * is 10 bit long, it may assume 2^10 distinct values. * Hence, scale = range / 2^10. The IIO_VAL_FRACTIONAL_LOG2 * return type indicates to the IIO API to divide *val by 2 to * the power of *val2 when returning from read_raw. */ ret = ad7292_vin_range_multiplier(st, chan->channel); if (ret < 0) return ret; *val = st->vref_mv * ret; *val2 = 10; return IIO_VAL_FRACTIONAL_LOG2; default: break; } return -EINVAL; } static const struct iio_info ad7292_info = { .read_raw = ad7292_read_raw, }; static int ad7292_probe(struct spi_device *spi) { struct ad7292_state *st; struct iio_dev *indio_dev; bool diff_channels = false; int ret; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; st = iio_priv(indio_dev); st->spi = spi; ret = ad7292_spi_reg_read(st, AD7292_REG_VENDOR_ID); if (ret != ADI_VENDOR_ID) { dev_err(&spi->dev, "Wrong vendor id 0x%x\n", ret); return -EINVAL; } ret = devm_regulator_get_enable_read_voltage(&spi->dev, "vref"); if (ret < 0 && ret != -ENODEV) return ret; st->vref_mv = ret == -ENODEV ? AD7292_INTERNAL_REF_MV : ret / 1000; indio_dev->name = spi_get_device_id(spi)->name; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = &ad7292_info; device_for_each_child_node_scoped(&spi->dev, child) { diff_channels = fwnode_property_read_bool(child, "diff-channels"); if (diff_channels) break; } if (diff_channels) { indio_dev->num_channels = ARRAY_SIZE(ad7292_channels_diff); indio_dev->channels = ad7292_channels_diff; } else { indio_dev->num_channels = ARRAY_SIZE(ad7292_channels); indio_dev->channels = ad7292_channels; } return devm_iio_device_register(&spi->dev, indio_dev); } static const struct spi_device_id ad7292_id_table[] = { { "ad7292", 0 }, {} }; MODULE_DEVICE_TABLE(spi, ad7292_id_table); static const struct of_device_id ad7292_of_match[] = { { .compatible = "adi,ad7292" }, { }, }; MODULE_DEVICE_TABLE(of, ad7292_of_match); static struct spi_driver ad7292_driver = { .driver = { .name = "ad7292", .of_match_table = ad7292_of_match, }, .probe = ad7292_probe, .id_table = ad7292_id_table, }; module_spi_driver(ad7292_driver); MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt1@gmail.com>"); MODULE_DESCRIPTION("Analog Devices AD7292 ADC driver"); MODULE_LICENSE("GPL v2");
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