// 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/iio/driver.h> #include <linux/iio/machine.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 struct iio_map rn5t618_maps[] = { IIO_MAP("VADP", "rn5t618-power", "vadp"), IIO_MAP("VUSB", "rn5t618-power", "vusb"), { /* sentinel */ } }; static void unregister_map(void *data) { struct iio_dev *iio_dev = (struct iio_dev *) data; iio_map_array_unregister(iio_dev); } 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->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; } ret = iio_map_array_register(iio_dev, rn5t618_maps); if (ret < 0) return ret; ret = devm_add_action_or_reset(adc->dev, unregister_map, iio_dev); if (ret < 0) 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");