| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Analog Devices AD7466/7/8 AD7476/5/7/8 (A) SPI ADC driver |
| * TI ADC081S/ADC101S/ADC121S 8/10/12-bit SPI ADC driver |
| * |
| * Copyright 2010 Analog Devices Inc. |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.h> |
| #include <linux/sysfs.h> |
| #include <linux/spi/spi.h> |
| #include <linux/regulator/consumer.h> |
| #include <linux/gpio/consumer.h> |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/bitops.h> |
| #include <linux/delay.h> |
| |
| #include <linux/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| #include <linux/iio/buffer.h> |
| #include <linux/iio/trigger_consumer.h> |
| #include <linux/iio/triggered_buffer.h> |
| |
| struct ad7476_state; |
| |
| struct ad7476_chip_info { |
| unsigned int int_vref_uv; |
| struct iio_chan_spec channel[2]; |
| /* channels used when convst gpio is defined */ |
| struct iio_chan_spec convst_channel[2]; |
| void (*reset)(struct ad7476_state *); |
| }; |
| |
| struct ad7476_state { |
| struct spi_device *spi; |
| const struct ad7476_chip_info *chip_info; |
| struct regulator *reg; |
| struct gpio_desc *convst_gpio; |
| struct spi_transfer xfer; |
| 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 one 16 bit sample and one 64 bit |
| * aligned 64 bit timestamp. |
| */ |
| unsigned char data[ALIGN(2, sizeof(s64)) + sizeof(s64)] |
| ____cacheline_aligned; |
| }; |
| |
| enum ad7476_supported_device_ids { |
| ID_AD7091R, |
| ID_AD7276, |
| ID_AD7277, |
| ID_AD7278, |
| ID_AD7466, |
| ID_AD7467, |
| ID_AD7468, |
| ID_AD7495, |
| ID_AD7940, |
| ID_ADC081S, |
| ID_ADC101S, |
| ID_ADC121S, |
| ID_ADS7866, |
| ID_ADS7867, |
| ID_ADS7868, |
| }; |
| |
| static void ad7091_convst(struct ad7476_state *st) |
| { |
| if (!st->convst_gpio) |
| return; |
| |
| gpiod_set_value(st->convst_gpio, 0); |
| udelay(1); /* CONVST pulse width: 10 ns min */ |
| gpiod_set_value(st->convst_gpio, 1); |
| udelay(1); /* Conversion time: 650 ns max */ |
| } |
| |
| static irqreturn_t ad7476_trigger_handler(int irq, void *p) |
| { |
| struct iio_poll_func *pf = p; |
| struct iio_dev *indio_dev = pf->indio_dev; |
| struct ad7476_state *st = iio_priv(indio_dev); |
| int b_sent; |
| |
| ad7091_convst(st); |
| |
| b_sent = spi_sync(st->spi, &st->msg); |
| if (b_sent < 0) |
| goto done; |
| |
| iio_push_to_buffers_with_timestamp(indio_dev, st->data, |
| iio_get_time_ns(indio_dev)); |
| done: |
| iio_trigger_notify_done(indio_dev->trig); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void ad7091_reset(struct ad7476_state *st) |
| { |
| /* Any transfers with 8 scl cycles will reset the device */ |
| spi_read(st->spi, st->data, 1); |
| } |
| |
| static int ad7476_scan_direct(struct ad7476_state *st) |
| { |
| int ret; |
| |
| ad7091_convst(st); |
| |
| ret = spi_sync(st->spi, &st->msg); |
| if (ret) |
| return ret; |
| |
| return be16_to_cpup((__be16 *)st->data); |
| } |
| |
| static int ad7476_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, |
| int *val2, |
| long m) |
| { |
| int ret; |
| struct ad7476_state *st = iio_priv(indio_dev); |
| int scale_uv; |
| |
| switch (m) { |
| case IIO_CHAN_INFO_RAW: |
| ret = iio_device_claim_direct_mode(indio_dev); |
| if (ret) |
| return ret; |
| ret = ad7476_scan_direct(st); |
| iio_device_release_direct_mode(indio_dev); |
| |
| if (ret < 0) |
| return ret; |
| *val = (ret >> st->chip_info->channel[0].scan_type.shift) & |
| GENMASK(st->chip_info->channel[0].scan_type.realbits - 1, 0); |
| return IIO_VAL_INT; |
| case IIO_CHAN_INFO_SCALE: |
| if (!st->chip_info->int_vref_uv) { |
| scale_uv = regulator_get_voltage(st->reg); |
| if (scale_uv < 0) |
| return scale_uv; |
| } else { |
| scale_uv = st->chip_info->int_vref_uv; |
| } |
| *val = scale_uv / 1000; |
| *val2 = chan->scan_type.realbits; |
| return IIO_VAL_FRACTIONAL_LOG2; |
| } |
| return -EINVAL; |
| } |
| |
| #define _AD7476_CHAN(bits, _shift, _info_mask_sep) \ |
| { \ |
| .type = IIO_VOLTAGE, \ |
| .indexed = 1, \ |
| .info_mask_separate = _info_mask_sep, \ |
| .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ |
| .scan_type = { \ |
| .sign = 'u', \ |
| .realbits = (bits), \ |
| .storagebits = 16, \ |
| .shift = (_shift), \ |
| .endianness = IIO_BE, \ |
| }, \ |
| } |
| |
| #define ADC081S_CHAN(bits) _AD7476_CHAN((bits), 12 - (bits), \ |
| BIT(IIO_CHAN_INFO_RAW)) |
| #define AD7476_CHAN(bits) _AD7476_CHAN((bits), 13 - (bits), \ |
| BIT(IIO_CHAN_INFO_RAW)) |
| #define AD7940_CHAN(bits) _AD7476_CHAN((bits), 15 - (bits), \ |
| BIT(IIO_CHAN_INFO_RAW)) |
| #define AD7091R_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), 0) |
| #define AD7091R_CONVST_CHAN(bits) _AD7476_CHAN((bits), 16 - (bits), \ |
| BIT(IIO_CHAN_INFO_RAW)) |
| #define ADS786X_CHAN(bits) _AD7476_CHAN((bits), 12 - (bits), \ |
| BIT(IIO_CHAN_INFO_RAW)) |
| |
| static const struct ad7476_chip_info ad7476_chip_info_tbl[] = { |
| [ID_AD7091R] = { |
| .channel[0] = AD7091R_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| .convst_channel[0] = AD7091R_CONVST_CHAN(12), |
| .convst_channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| .reset = ad7091_reset, |
| }, |
| [ID_AD7276] = { |
| .channel[0] = AD7940_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7277] = { |
| .channel[0] = AD7940_CHAN(10), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7278] = { |
| .channel[0] = AD7940_CHAN(8), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7466] = { |
| .channel[0] = AD7476_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7467] = { |
| .channel[0] = AD7476_CHAN(10), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7468] = { |
| .channel[0] = AD7476_CHAN(8), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_AD7495] = { |
| .channel[0] = AD7476_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| .int_vref_uv = 2500000, |
| }, |
| [ID_AD7940] = { |
| .channel[0] = AD7940_CHAN(14), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADC081S] = { |
| .channel[0] = ADC081S_CHAN(8), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADC101S] = { |
| .channel[0] = ADC081S_CHAN(10), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADC121S] = { |
| .channel[0] = ADC081S_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADS7866] = { |
| .channel[0] = ADS786X_CHAN(12), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADS7867] = { |
| .channel[0] = ADS786X_CHAN(10), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| [ID_ADS7868] = { |
| .channel[0] = ADS786X_CHAN(8), |
| .channel[1] = IIO_CHAN_SOFT_TIMESTAMP(1), |
| }, |
| }; |
| |
| static const struct iio_info ad7476_info = { |
| .read_raw = &ad7476_read_raw, |
| }; |
| |
| static void ad7476_reg_disable(void *data) |
| { |
| struct ad7476_state *st = data; |
| |
| regulator_disable(st->reg); |
| } |
| |
| static int ad7476_probe(struct spi_device *spi) |
| { |
| struct ad7476_state *st; |
| struct iio_dev *indio_dev; |
| int ret; |
| |
| indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| st = iio_priv(indio_dev); |
| st->chip_info = |
| &ad7476_chip_info_tbl[spi_get_device_id(spi)->driver_data]; |
| |
| st->reg = devm_regulator_get(&spi->dev, "vcc"); |
| if (IS_ERR(st->reg)) |
| return PTR_ERR(st->reg); |
| |
| ret = regulator_enable(st->reg); |
| if (ret) |
| return ret; |
| |
| ret = devm_add_action_or_reset(&spi->dev, ad7476_reg_disable, |
| st); |
| if (ret) |
| return ret; |
| |
| st->convst_gpio = devm_gpiod_get_optional(&spi->dev, |
| "adi,conversion-start", |
| GPIOD_OUT_LOW); |
| if (IS_ERR(st->convst_gpio)) |
| return PTR_ERR(st->convst_gpio); |
| |
| spi_set_drvdata(spi, indio_dev); |
| |
| st->spi = spi; |
| |
| indio_dev->name = spi_get_device_id(spi)->name; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = st->chip_info->channel; |
| indio_dev->num_channels = 2; |
| indio_dev->info = &ad7476_info; |
| |
| if (st->convst_gpio) |
| indio_dev->channels = st->chip_info->convst_channel; |
| /* Setup default message */ |
| |
| st->xfer.rx_buf = &st->data; |
| st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8; |
| |
| spi_message_init(&st->msg); |
| spi_message_add_tail(&st->xfer, &st->msg); |
| |
| ret = iio_triggered_buffer_setup(indio_dev, NULL, |
| &ad7476_trigger_handler, NULL); |
| if (ret) |
| goto error_disable_reg; |
| |
| if (st->chip_info->reset) |
| st->chip_info->reset(st); |
| |
| ret = iio_device_register(indio_dev); |
| if (ret) |
| goto error_ring_unregister; |
| return 0; |
| |
| error_ring_unregister: |
| iio_triggered_buffer_cleanup(indio_dev); |
| error_disable_reg: |
| regulator_disable(st->reg); |
| |
| return ret; |
| } |
| |
| static const struct spi_device_id ad7476_id[] = { |
| {"ad7091", ID_AD7091R}, |
| {"ad7091r", ID_AD7091R}, |
| {"ad7273", ID_AD7277}, |
| {"ad7274", ID_AD7276}, |
| {"ad7276", ID_AD7276}, |
| {"ad7277", ID_AD7277}, |
| {"ad7278", ID_AD7278}, |
| {"ad7466", ID_AD7466}, |
| {"ad7467", ID_AD7467}, |
| {"ad7468", ID_AD7468}, |
| {"ad7475", ID_AD7466}, |
| {"ad7476", ID_AD7466}, |
| {"ad7476a", ID_AD7466}, |
| {"ad7477", ID_AD7467}, |
| {"ad7477a", ID_AD7467}, |
| {"ad7478", ID_AD7468}, |
| {"ad7478a", ID_AD7468}, |
| {"ad7495", ID_AD7495}, |
| {"ad7910", ID_AD7467}, |
| {"ad7920", ID_AD7466}, |
| {"ad7940", ID_AD7940}, |
| {"adc081s", ID_ADC081S}, |
| {"adc101s", ID_ADC101S}, |
| {"adc121s", ID_ADC121S}, |
| {"ads7866", ID_ADS7866}, |
| {"ads7867", ID_ADS7867}, |
| {"ads7868", ID_ADS7868}, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(spi, ad7476_id); |
| |
| static struct spi_driver ad7476_driver = { |
| .driver = { |
| .name = "ad7476", |
| }, |
| .probe = ad7476_probe, |
| .id_table = ad7476_id, |
| }; |
| module_spi_driver(ad7476_driver); |
| |
| MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); |
| MODULE_DESCRIPTION("Analog Devices AD7476 and similar 1-channel ADCs"); |
| MODULE_LICENSE("GPL v2"); |