|  | // 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/err.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/bitops.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]; | 
|  | void (*reset)(struct ad7476_state *); | 
|  | }; | 
|  |  | 
|  | struct ad7476_state { | 
|  | struct spi_device		*spi; | 
|  | const struct ad7476_chip_info	*chip_info; | 
|  | struct regulator		*reg; | 
|  | 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 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; | 
|  |  | 
|  | 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; | 
|  |  | 
|  | 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 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), | 
|  | .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 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; | 
|  |  | 
|  | spi_set_drvdata(spi, indio_dev); | 
|  |  | 
|  | st->spi = spi; | 
|  |  | 
|  | /* Establish that the iio_dev is a child of the spi device */ | 
|  | indio_dev->dev.parent = &spi->dev; | 
|  | indio_dev->dev.of_node = spi->dev.of_node; | 
|  | 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; | 
|  | /* 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 int ad7476_remove(struct spi_device *spi) | 
|  | { | 
|  | struct iio_dev *indio_dev = spi_get_drvdata(spi); | 
|  | struct ad7476_state *st = iio_priv(indio_dev); | 
|  |  | 
|  | iio_device_unregister(indio_dev); | 
|  | iio_triggered_buffer_cleanup(indio_dev); | 
|  | regulator_disable(st->reg); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct spi_device_id ad7476_id[] = { | 
|  | {"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, | 
|  | .remove		= ad7476_remove, | 
|  | .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"); |