| // 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; |
| }; |
| |
| enum rn5t618_channels { |
| LIMMON = 0, |
| VBAT, |
| VADP, |
| VUSB, |
| VSYS, |
| VTHM, |
| AIN1, |
| AIN0 |
| }; |
| |
| static const struct u16_fract 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_set_bits(adc->rn5t618->regmap, RN5T618_ADCCNT3, |
| 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 const struct iio_map rn5t618_maps[] = { |
| IIO_MAP("VADP", "rn5t618-power", "vadp"), |
| IIO_MAP("VUSB", "rn5t618-power", "vusb"), |
| { /* sentinel */ } |
| }; |
| |
| 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 = devm_iio_map_array_register(adc->dev, iio_dev, rn5t618_maps); |
| 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"); |