iio:adc: Add support for AD7766/AD7767 (aa16c6bd) · Commits · 戴 / test

drivers/iio/adc/Kconfig

+12 −0

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		@@ -58,6 +58,18 @@ config AD7476
		To compile this driver as a module, choose M here: the
		module will be called ad7476.

		config AD7766
		tristate "Analog Devices AD7766/AD7767 ADC driver"
		depends on SPI_MASTER
		select IIO_BUFFER
		select IIO_TRIGGERED_BUFFER
		help
		Say yes here to build support for Analog Devices AD7766, AD7766-1,
		AD7766-2, AD7767, AD7767-1, AD7767-2 SPI analog to digital converters.

		To compile this driver as a module, choose M here: the module will be
		called ad7766.

		config AD7791
		tristate "Analog Devices AD7791 ADC driver"
		depends on SPI

drivers/iio/adc/Makefile

+1 −0

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		@@ -9,6 +9,7 @@ obj-$(CONFIG_AD7291) += ad7291.o
		obj-$(CONFIG_AD7298) += ad7298.o
		obj-$(CONFIG_AD7923) += ad7923.o
		obj-$(CONFIG_AD7476) += ad7476.o
		obj-$(CONFIG_AD7766) += ad7766.o
		obj-$(CONFIG_AD7791) += ad7791.o
		obj-$(CONFIG_AD7793) += ad7793.o
		obj-$(CONFIG_AD7887) += ad7887.o

drivers/iio/adc/ad7766.c

0 → 100644

+330 −0

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		/*
		* AD7766/AD7767 SPI ADC driver
		*
		* Copyright 2016 Analog Devices Inc.
		*
		* Licensed under the GPL-2 or later.
		*/

		#include <linux/clk.h>
		#include <linux/delay.h>
		#include <linux/device.h>
		#include <linux/err.h>
		#include <linux/gpio/consumer.h>
		#include <linux/module.h>
		#include <linux/regulator/consumer.h>
		#include <linux/slab.h>
		#include <linux/spi/spi.h>

		#include <linux/iio/iio.h>
		#include <linux/iio/buffer.h>
		#include <linux/iio/trigger.h>
		#include <linux/iio/trigger_consumer.h>
		#include <linux/iio/triggered_buffer.h>

		struct ad7766_chip_info {
		unsigned int decimation_factor;
		};

		enum {
		AD7766_SUPPLY_AVDD = 0,
		AD7766_SUPPLY_DVDD = 1,
		AD7766_SUPPLY_VREF = 2,
		AD7766_NUM_SUPPLIES = 3
		};

		struct ad7766 {
		const struct ad7766_chip_info *chip_info;
		struct spi_device *spi;
		struct clk *mclk;
		struct gpio_desc *pd_gpio;
		struct regulator_bulk_data reg[AD7766_NUM_SUPPLIES];

		struct iio_trigger *trig;

		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 24 bit sample and one 64 bit
		* aligned 64 bit timestamp.
		*/
		unsigned char data[ALIGN(3, sizeof(s64)) + sizeof(s64)]
		____cacheline_aligned;
		};

		/*
		* AD7766 and AD7767 variations are interface compatible, the main difference is
		* analog performance. Both parts will use the same ID.
		*/
		enum ad7766_device_ids {
		ID_AD7766,
		ID_AD7766_1,
		ID_AD7766_2,
		};

		static irqreturn_t ad7766_trigger_handler(int irq, void *p)
		{
		struct iio_poll_func *pf = p;
		struct iio_dev *indio_dev = pf->indio_dev;
		struct ad7766 *ad7766 = iio_priv(indio_dev);
		int ret;

		ret = spi_sync(ad7766->spi, &ad7766->msg);
		if (ret < 0)
		goto done;

		iio_push_to_buffers_with_timestamp(indio_dev, ad7766->data,
		pf->timestamp);
		done:
		iio_trigger_notify_done(indio_dev->trig);

		return IRQ_HANDLED;
		}

		static int ad7766_preenable(struct iio_dev *indio_dev)
		{
		struct ad7766 *ad7766 = iio_priv(indio_dev);
		int ret;

		ret = regulator_bulk_enable(ARRAY_SIZE(ad7766->reg), ad7766->reg);
		if (ret < 0) {
		dev_err(&ad7766->spi->dev, "Failed to enable supplies: %d\n",
		ret);
		return ret;
		}

		ret = clk_prepare_enable(ad7766->mclk);
		if (ret < 0) {
		dev_err(&ad7766->spi->dev, "Failed to enable MCLK: %d\n", ret);
		regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg);
		return ret;
		}

		if (ad7766->pd_gpio)
		gpiod_set_value(ad7766->pd_gpio, 0);

		return 0;
		}

		static int ad7766_postdisable(struct iio_dev *indio_dev)
		{
		struct ad7766 *ad7766 = iio_priv(indio_dev);

		if (ad7766->pd_gpio)
		gpiod_set_value(ad7766->pd_gpio, 1);

		/*
		* The PD pin is synchronous to the clock, so give it some time to
		* notice the change before we disable the clock.
		*/
		msleep(20);

		clk_disable_unprepare(ad7766->mclk);
		regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg);

		return 0;
		}

		static int ad7766_read_raw(struct iio_dev *indio_dev,
		const struct iio_chan_spec chan, int val, int *val2, long info)
		{
		struct ad7766 *ad7766 = iio_priv(indio_dev);
		struct regulator *vref = ad7766->reg[AD7766_SUPPLY_VREF].consumer;
		int scale_uv;

		switch (info) {
		case IIO_CHAN_INFO_SCALE:
		scale_uv = regulator_get_voltage(vref);
		if (scale_uv < 0)
		return scale_uv;
		*val = scale_uv / 1000;
		*val2 = chan->scan_type.realbits;
		return IIO_VAL_FRACTIONAL_LOG2;
		case IIO_CHAN_INFO_SAMP_FREQ:
		*val = clk_get_rate(ad7766->mclk) /
		ad7766->chip_info->decimation_factor;
		return IIO_VAL_INT;
		}
		return -EINVAL;
		}

		static const struct iio_chan_spec ad7766_channels[] = {
		{
		.type = IIO_VOLTAGE,
		.indexed = 1,
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
		.scan_type = {
		.sign = 's',
		.realbits = 24,
		.storagebits = 32,
		.endianness = IIO_BE,
		},
		},
		IIO_CHAN_SOFT_TIMESTAMP(1),
		};

		static const struct ad7766_chip_info ad7766_chip_info[] = {
		[ID_AD7766] = {
		.decimation_factor = 8,
		},
		[ID_AD7766_1] = {
		.decimation_factor = 16,
		},
		[ID_AD7766_2] = {
		.decimation_factor = 32,
		},
		};

		static const struct iio_buffer_setup_ops ad7766_buffer_setup_ops = {
		.preenable = &ad7766_preenable,
		.postenable = &iio_triggered_buffer_postenable,
		.predisable = &iio_triggered_buffer_predisable,
		.postdisable = &ad7766_postdisable,
		};

		static const struct iio_info ad7766_info = {
		.driver_module = THIS_MODULE,
		.read_raw = &ad7766_read_raw,
		};

		static irqreturn_t ad7766_irq(int irq, void *private)
		{
		iio_trigger_poll(private);
		return IRQ_HANDLED;
		}

		static int ad7766_set_trigger_state(struct iio_trigger *trig, bool enable)
		{
		struct ad7766 *ad7766 = iio_trigger_get_drvdata(trig);

		if (enable)
		enable_irq(ad7766->spi->irq);
		else
		disable_irq(ad7766->spi->irq);

		return 0;
		}

		static const struct iio_trigger_ops ad7766_trigger_ops = {
		.owner = THIS_MODULE,
		.set_trigger_state = ad7766_set_trigger_state,
		.validate_device = iio_trigger_validate_own_device,
		};

		static int ad7766_probe(struct spi_device *spi)
		{
		const struct spi_device_id *id = spi_get_device_id(spi);
		struct iio_dev *indio_dev;
		struct ad7766 *ad7766;
		int ret;

		indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*ad7766));
		if (!indio_dev)
		return -ENOMEM;

		ad7766 = iio_priv(indio_dev);
		ad7766->chip_info = &ad7766_chip_info[id->driver_data];

		ad7766->mclk = devm_clk_get(&spi->dev, "mclk");
		if (IS_ERR(ad7766->mclk))
		return PTR_ERR(ad7766->mclk);

		ad7766->reg[AD7766_SUPPLY_AVDD].supply = "avdd";
		ad7766->reg[AD7766_SUPPLY_DVDD].supply = "dvdd";
		ad7766->reg[AD7766_SUPPLY_VREF].supply = "vref";

		ret = devm_regulator_bulk_get(&spi->dev, ARRAY_SIZE(ad7766->reg),
		ad7766->reg);
		if (IS_ERR(ad7766->reg))
		return PTR_ERR(ad7766->reg);

		ad7766->pd_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
		GPIOD_OUT_HIGH);
		if (IS_ERR(ad7766->pd_gpio))
		return PTR_ERR(ad7766->pd_gpio);

		indio_dev->dev.parent = &spi->dev;
		indio_dev->name = spi_get_device_id(spi)->name;
		indio_dev->modes = INDIO_DIRECT_MODE;
		indio_dev->channels = ad7766_channels;
		indio_dev->num_channels = ARRAY_SIZE(ad7766_channels);
		indio_dev->info = &ad7766_info;

		if (spi->irq > 0) {
		ad7766->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
		indio_dev->name, indio_dev->id);
		if (!ad7766->trig)
		return -ENOMEM;

		ad7766->trig->ops = &ad7766_trigger_ops;
		ad7766->trig->dev.parent = &spi->dev;
		iio_trigger_set_drvdata(ad7766->trig, ad7766);

		ret = devm_request_irq(&spi->dev, spi->irq, ad7766_irq,
		IRQF_TRIGGER_FALLING, dev_name(&spi->dev),
		ad7766->trig);
		if (ret < 0)
		return ret;

		/*
		* The device generates interrupts as long as it is powered up.
		* Some platforms might not allow the option to power it down so
		* disable the interrupt to avoid extra load on the system
		*/
		disable_irq(spi->irq);

		ret = devm_iio_trigger_register(&spi->dev, ad7766->trig);
		if (ret)
		return ret;
		}

		spi_set_drvdata(spi, indio_dev);

		ad7766->spi = spi;

		/* First byte always 0 */
		ad7766->xfer.rx_buf = &ad7766->data[1];
		ad7766->xfer.len = 3;

		spi_message_init(&ad7766->msg);
		spi_message_add_tail(&ad7766->xfer, &ad7766->msg);

		ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
		&iio_pollfunc_store_time, &ad7766_trigger_handler,
		&ad7766_buffer_setup_ops);
		if (ret)
		return ret;

		ret = devm_iio_device_register(&spi->dev, indio_dev);
		if (ret)
		return ret;
		return 0;
		}

		static const struct spi_device_id ad7766_id[] = {
		{"ad7766", ID_AD7766},
		{"ad7766-1", ID_AD7766_1},
		{"ad7766-2", ID_AD7766_2},
		{"ad7767", ID_AD7766},
		{"ad7767-1", ID_AD7766_1},
		{"ad7767-2", ID_AD7766_2},
		{}
		};
		MODULE_DEVICE_TABLE(spi, ad7766_id);

		static struct spi_driver ad7766_driver = {
		.driver = {
		.name = "ad7766",
		},
		.probe = ad7766_probe,
		.id_table = ad7766_id,
		};
		module_spi_driver(ad7766_driver);

		MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
		MODULE_DESCRIPTION("Analog Devices AD7766 and AD7767 ADCs driver support");
		MODULE_LICENSE("GPL v2");

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