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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * MEN 16z188 Analog to Digial Converter4 *5 * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)6 * Author: Johannes Thumshirn <johannes.thumshirn@men.de>7 */8 9#include <linux/kernel.h>10#include <linux/module.h>11#include <linux/mcb.h>12#include <linux/io.h>13#include <linux/iio/iio.h>14 15#define Z188_ADC_MAX_CHAN 816#define Z188_ADC_GAIN 0x070000017#define Z188_MODE_VOLTAGE BIT(27)18#define Z188_CFG_AUTO 0x119#define Z188_CTRL_REG 0x4020 21#define ADC_DATA(x) (((x) >> 2) & 0x7ffffc)22#define ADC_OVR(x) ((x) & 0x1)23 24struct z188_adc {25 struct resource *mem;26 void __iomem *base;27};28 29#define Z188_ADC_CHANNEL(idx) { \30 .type = IIO_VOLTAGE, \31 .indexed = 1, \32 .channel = (idx), \33 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \34}35 36static const struct iio_chan_spec z188_adc_iio_channels[] = {37 Z188_ADC_CHANNEL(0),38 Z188_ADC_CHANNEL(1),39 Z188_ADC_CHANNEL(2),40 Z188_ADC_CHANNEL(3),41 Z188_ADC_CHANNEL(4),42 Z188_ADC_CHANNEL(5),43 Z188_ADC_CHANNEL(6),44 Z188_ADC_CHANNEL(7),45};46 47static int z188_iio_read_raw(struct iio_dev *iio_dev,48 struct iio_chan_spec const *chan,49 int *val,50 int *val2,51 long info)52{53 struct z188_adc *adc = iio_priv(iio_dev);54 int ret;55 u16 tmp;56 57 switch (info) {58 case IIO_CHAN_INFO_RAW:59 tmp = readw(adc->base + chan->channel * 4);60 61 if (ADC_OVR(tmp)) {62 dev_info(&iio_dev->dev,63 "Oversampling error on ADC channel %d\n",64 chan->channel);65 return -EIO;66 }67 *val = ADC_DATA(tmp);68 ret = IIO_VAL_INT;69 break;70 default:71 ret = -EINVAL;72 break;73 }74 75 return ret;76}77 78static const struct iio_info z188_adc_info = {79 .read_raw = &z188_iio_read_raw,80};81 82static void men_z188_config_channels(void __iomem *addr)83{84 int i;85 u32 cfg;86 u32 ctl;87 88 ctl = readl(addr + Z188_CTRL_REG);89 ctl |= Z188_CFG_AUTO;90 writel(ctl, addr + Z188_CTRL_REG);91 92 for (i = 0; i < Z188_ADC_MAX_CHAN; i++) {93 cfg = readl(addr + i);94 cfg &= ~Z188_ADC_GAIN;95 cfg |= Z188_MODE_VOLTAGE;96 writel(cfg, addr + i);97 }98}99 100static int men_z188_probe(struct mcb_device *dev,101 const struct mcb_device_id *id)102{103 struct z188_adc *adc;104 struct iio_dev *indio_dev;105 struct resource *mem;106 int ret;107 108 indio_dev = devm_iio_device_alloc(&dev->dev, sizeof(struct z188_adc));109 if (!indio_dev)110 return -ENOMEM;111 112 adc = iio_priv(indio_dev);113 indio_dev->name = "z188-adc";114 indio_dev->info = &z188_adc_info;115 indio_dev->modes = INDIO_DIRECT_MODE;116 indio_dev->channels = z188_adc_iio_channels;117 indio_dev->num_channels = ARRAY_SIZE(z188_adc_iio_channels);118 119 mem = mcb_request_mem(dev, "z188-adc");120 if (IS_ERR(mem))121 return PTR_ERR(mem);122 123 adc->base = ioremap(mem->start, resource_size(mem));124 if (adc->base == NULL)125 goto err;126 127 men_z188_config_channels(adc->base);128 129 adc->mem = mem;130 mcb_set_drvdata(dev, indio_dev);131 132 ret = iio_device_register(indio_dev);133 if (ret)134 goto err_unmap;135 136 return 0;137 138err_unmap:139 iounmap(adc->base);140err:141 mcb_release_mem(mem);142 return -ENXIO;143}144 145static void men_z188_remove(struct mcb_device *dev)146{147 struct iio_dev *indio_dev = mcb_get_drvdata(dev);148 struct z188_adc *adc = iio_priv(indio_dev);149 150 iio_device_unregister(indio_dev);151 iounmap(adc->base);152 mcb_release_mem(adc->mem);153}154 155static const struct mcb_device_id men_z188_ids[] = {156 { .device = 0xbc },157 { }158};159MODULE_DEVICE_TABLE(mcb, men_z188_ids);160 161static struct mcb_driver men_z188_driver = {162 .driver = {163 .name = "z188-adc",164 },165 .probe = men_z188_probe,166 .remove = men_z188_remove,167 .id_table = men_z188_ids,168};169module_mcb_driver(men_z188_driver);170 171MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");172MODULE_LICENSE("GPL");173MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core");174MODULE_ALIAS("mcb:16z188");175MODULE_IMPORT_NS(MCB);176