cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

men_z188_adc.c (3729B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * MEN 16z188 Analog to Digial Converter
      4 *
      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	8
     16#define Z188_ADC_GAIN		0x0700000
     17#define Z188_MODE_VOLTAGE	BIT(27)
     18#define Z188_CFG_AUTO		0x1
     19#define Z188_CTRL_REG		0x40
     20
     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		.owner = THIS_MODULE,
    165	},
    166	.probe = men_z188_probe,
    167	.remove = men_z188_remove,
    168	.id_table = men_z188_ids,
    169};
    170module_mcb_driver(men_z188_driver);
    171
    172MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
    173MODULE_LICENSE("GPL");
    174MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core");
    175MODULE_ALIAS("mcb:16z188");
    176MODULE_IMPORT_NS(MCB);