iio: adc: rn5t618: Add ADC driver for RN5T618/RC5T619 (87a25333) · Commits · EulixOS / Software / Kernel

drivers/iio/adc/Kconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -783,6 +783,16 @@ config RCAR_GYRO_ADC
		To compile this driver as a module, choose M here: the
		module will be called rcar-gyroadc.

		config RN5T618_ADC
		tristate "ADC for the RN5T618/RC5T619 family of chips"
		depends on MFD_RN5T618
		help
		Say yes here to build support for the integrated ADC inside the
		RN5T618/619 series PMICs:

		This driver can also be built as a module. If so, the module
		will be called rn5t618-adc.

		config ROCKCHIP_SARADC
		tristate "Rockchip SARADC driver"
		depends on ARCH_ROCKCHIP \|\| (ARM && COMPILE_TEST)

drivers/iio/adc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -74,6 +74,7 @@ obj-$(CONFIG_QCOM_VADC_COMMON) += qcom-vadc-common.o
		obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
		obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o
		obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o
		obj-$(CONFIG_RN5T618_ADC) += rn5t618-adc.o
		obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
		obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o
		obj-$(CONFIG_SPEAR_ADC) += spear_adc.o

drivers/iio/adc/rn5t618-adc.c

0 → 100644

+256 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0+
		/*
		* ADC driver for the RICOH RN5T618 power management chip family
		*
		* Copyright (C) 2019 Andreas Kemnade
		*/

		#include <linux/kernel.h>
		#include <linux/device.h>
		#include <linux/errno.h>
		#include <linux/interrupt.h>
		#include <linux/init.h>
		#include <linux/module.h>
		#include <linux/mfd/rn5t618.h>
		#include <linux/platform_device.h>
		#include <linux/completion.h>
		#include <linux/regmap.h>
		#include <linux/iio/iio.h>
		#include <linux/slab.h>

		#define RN5T618_ADC_CONVERSION_TIMEOUT (msecs_to_jiffies(500))
		#define RN5T618_REFERENCE_VOLT 2500

		/* mask for selecting channels for single conversion */
		#define RN5T618_ADCCNT3_CHANNEL_MASK 0x7
		/* average 4-time conversion mode */
		#define RN5T618_ADCCNT3_AVG BIT(3)
		/* set for starting a single conversion, gets cleared by hw when done */
		#define RN5T618_ADCCNT3_GODONE BIT(4)
		/* automatic conversion, period is in ADCCNT2, selected channels are
		* in ADCCNT1
		*/
		#define RN5T618_ADCCNT3_AUTO BIT(5)
		#define RN5T618_ADCEND_IRQ BIT(0)

		struct rn5t618_adc_data {
		struct device *dev;
		struct rn5t618 *rn5t618;
		struct completion conv_completion;
		int irq;
		};

		struct rn5t618_channel_ratios {
		u16 numerator;
		u16 denominator;
		};

		enum rn5t618_channels {
		LIMMON = 0,
		VBAT,
		VADP,
		VUSB,
		VSYS,
		VTHM,
		AIN1,
		AIN0
		};

		static const struct rn5t618_channel_ratios rn5t618_ratios[8] = {
		[LIMMON] = {50, 32}, /* measured across 20mOhm, amplified by 32 */
		[VBAT] = {2, 1},
		[VADP] = {3, 1},
		[VUSB] = {3, 1},
		[VSYS] = {3, 1},
		[VTHM] = {1, 1},
		[AIN1] = {1, 1},
		[AIN0] = {1, 1},
		};

		static int rn5t618_read_adc_reg(struct rn5t618 rn5t618, int reg, u16 val)
		{
		u8 data[2];
		int ret;

		ret = regmap_bulk_read(rn5t618->regmap, reg, data, sizeof(data));
		if (ret < 0)
		return ret;

		*val = (data[0] << 4) \| (data[1] & 0xF);

		return 0;
		}

		static irqreturn_t rn5t618_adc_irq(int irq, void *data)
		{
		struct rn5t618_adc_data *adc = data;
		unsigned int r = 0;
		int ret;

		/* clear low & high threshold irqs */
		regmap_write(adc->rn5t618->regmap, RN5T618_IR_ADC1, 0);
		regmap_write(adc->rn5t618->regmap, RN5T618_IR_ADC2, 0);

		ret = regmap_read(adc->rn5t618->regmap, RN5T618_IR_ADC3, &r);
		if (ret < 0)
		dev_err(adc->dev, "failed to read IRQ status: %d\n", ret);

		regmap_write(adc->rn5t618->regmap, RN5T618_IR_ADC3, 0);

		if (r & RN5T618_ADCEND_IRQ)
		complete(&adc->conv_completion);

		return IRQ_HANDLED;
		}

		static int rn5t618_adc_read(struct iio_dev *iio_dev,
		const struct iio_chan_spec *chan,
		int val, int val2, long mask)
		{
		struct rn5t618_adc_data *adc = iio_priv(iio_dev);
		u16 raw;
		int ret;

		if (mask == IIO_CHAN_INFO_SCALE) {
		val = RN5T618_REFERENCE_VOLT
		rn5t618_ratios[chan->channel].numerator;
		val2 = rn5t618_ratios[chan->channel].denominator 4095;

		return IIO_VAL_FRACTIONAL;
		}

		/* select channel */
		ret = regmap_update_bits(adc->rn5t618->regmap, RN5T618_ADCCNT3,
		RN5T618_ADCCNT3_CHANNEL_MASK,
		chan->channel);
		if (ret < 0)
		return ret;

		ret = regmap_write(adc->rn5t618->regmap, RN5T618_EN_ADCIR3,
		RN5T618_ADCEND_IRQ);
		if (ret < 0)
		return ret;

		ret = regmap_update_bits(adc->rn5t618->regmap, RN5T618_ADCCNT3,
		RN5T618_ADCCNT3_AVG,
		mask == IIO_CHAN_INFO_AVERAGE_RAW ?
		RN5T618_ADCCNT3_AVG : 0);
		if (ret < 0)
		return ret;

		init_completion(&adc->conv_completion);
		/* single conversion */
		ret = regmap_update_bits(adc->rn5t618->regmap, RN5T618_ADCCNT3,
		RN5T618_ADCCNT3_GODONE,
		RN5T618_ADCCNT3_GODONE);
		if (ret < 0)
		return ret;

		ret = wait_for_completion_timeout(&adc->conv_completion,
		RN5T618_ADC_CONVERSION_TIMEOUT);
		if (ret == 0) {
		dev_warn(adc->dev, "timeout waiting for adc result\n");
		return -ETIMEDOUT;
		}

		ret = rn5t618_read_adc_reg(adc->rn5t618,
		RN5T618_ILIMDATAH + 2 * chan->channel,
		&raw);
		if (ret < 0)
		return ret;

		*val = raw;

		return IIO_VAL_INT;
		}

		static const struct iio_info rn5t618_adc_iio_info = {
		.read_raw = &rn5t618_adc_read,
		};

		#define RN5T618_ADC_CHANNEL(_channel, _type, _name) { \
		.type = _type, \
		.channel = _channel, \
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \| \
		BIT(IIO_CHAN_INFO_AVERAGE_RAW) \| \
		BIT(IIO_CHAN_INFO_SCALE), \
		.datasheet_name = _name, \
		.indexed = 1. \
		}

		static const struct iio_chan_spec rn5t618_adc_iio_channels[] = {
		RN5T618_ADC_CHANNEL(LIMMON, IIO_CURRENT, "LIMMON"),
		RN5T618_ADC_CHANNEL(VBAT, IIO_VOLTAGE, "VBAT"),
		RN5T618_ADC_CHANNEL(VADP, IIO_VOLTAGE, "VADP"),
		RN5T618_ADC_CHANNEL(VUSB, IIO_VOLTAGE, "VUSB"),
		RN5T618_ADC_CHANNEL(VSYS, IIO_VOLTAGE, "VSYS"),
		RN5T618_ADC_CHANNEL(VTHM, IIO_VOLTAGE, "VTHM"),
		RN5T618_ADC_CHANNEL(AIN1, IIO_VOLTAGE, "AIN1"),
		RN5T618_ADC_CHANNEL(AIN0, IIO_VOLTAGE, "AIN0")
		};

		static int rn5t618_adc_probe(struct platform_device *pdev)
		{
		int ret;
		struct iio_dev *iio_dev;
		struct rn5t618_adc_data *adc;
		struct rn5t618 *rn5t618 = dev_get_drvdata(pdev->dev.parent);

		iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
		if (!iio_dev) {
		dev_err(&pdev->dev, "failed allocating iio device\n");
		return -ENOMEM;
		}

		adc = iio_priv(iio_dev);
		adc->dev = &pdev->dev;
		adc->rn5t618 = rn5t618;

		if (rn5t618->irq_data)
		adc->irq = regmap_irq_get_virq(rn5t618->irq_data,
		RN5T618_IRQ_ADC);

		if (adc->irq <= 0) {
		dev_err(&pdev->dev, "get virq failed\n");
		return -EINVAL;
		}

		init_completion(&adc->conv_completion);

		iio_dev->name = dev_name(&pdev->dev);
		iio_dev->dev.parent = &pdev->dev;
		iio_dev->info = &rn5t618_adc_iio_info;
		iio_dev->modes = INDIO_DIRECT_MODE;
		iio_dev->channels = rn5t618_adc_iio_channels;
		iio_dev->num_channels = ARRAY_SIZE(rn5t618_adc_iio_channels);

		/* stop any auto-conversion */
		ret = regmap_write(rn5t618->regmap, RN5T618_ADCCNT3, 0);
		if (ret < 0)
		return ret;

		platform_set_drvdata(pdev, iio_dev);

		ret = devm_request_threaded_irq(adc->dev, adc->irq, NULL,
		rn5t618_adc_irq,
		IRQF_ONESHOT, dev_name(adc->dev),
		adc);
		if (ret < 0) {
		dev_err(adc->dev, "request irq %d failed: %d\n", adc->irq, ret);
		return ret;
		}

		return devm_iio_device_register(adc->dev, iio_dev);
		}

		static struct platform_driver rn5t618_adc_driver = {
		.driver = {
		.name = "rn5t618-adc",
		},
		.probe = rn5t618_adc_probe,
		};

		module_platform_driver(rn5t618_adc_driver);
		MODULE_ALIAS("platform:rn5t618-adc");
		MODULE_DESCRIPTION("RICOH RN5T618 ADC driver");
		MODULE_LICENSE("GPL");