cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ad5592r.c (4053B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * AD5592R Digital <-> Analog converters driver
      4 *
      5 * Copyright 2015-2016 Analog Devices Inc.
      6 * Author: Paul Cercueil <paul.cercueil@analog.com>
      7 */
      8
      9#include "ad5592r-base.h"
     10
     11#include <linux/bitops.h>
     12#include <linux/module.h>
     13#include <linux/mod_devicetable.h>
     14#include <linux/spi/spi.h>
     15
     16#define AD5592R_GPIO_READBACK_EN	BIT(10)
     17#define AD5592R_LDAC_READBACK_EN	BIT(6)
     18
     19static int ad5592r_spi_wnop_r16(struct ad5592r_state *st, __be16 *buf)
     20{
     21	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
     22	struct spi_transfer t = {
     23			.tx_buf	= &st->spi_msg_nop,
     24			.rx_buf	= buf,
     25			.len = 2
     26		};
     27
     28	st->spi_msg_nop = 0; /* NOP */
     29
     30	return spi_sync_transfer(spi, &t, 1);
     31}
     32
     33static int ad5592r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
     34{
     35	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
     36
     37	st->spi_msg = cpu_to_be16(BIT(15) | (chan << 12) | value);
     38
     39	return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
     40}
     41
     42static int ad5592r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
     43{
     44	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
     45	int ret;
     46
     47	st->spi_msg = cpu_to_be16((AD5592R_REG_ADC_SEQ << 11) | BIT(chan));
     48
     49	ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
     50	if (ret)
     51		return ret;
     52
     53	/*
     54	 * Invalid data:
     55	 * See Figure 40. Single-Channel ADC Conversion Sequence
     56	 */
     57	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
     58	if (ret)
     59		return ret;
     60
     61	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
     62	if (ret)
     63		return ret;
     64
     65	*value = be16_to_cpu(st->spi_msg);
     66
     67	return 0;
     68}
     69
     70static int ad5592r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
     71{
     72	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
     73
     74	st->spi_msg = cpu_to_be16((reg << 11) | value);
     75
     76	return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
     77}
     78
     79static int ad5592r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
     80{
     81	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
     82	int ret;
     83
     84	st->spi_msg = cpu_to_be16((AD5592R_REG_LDAC << 11) |
     85				   AD5592R_LDAC_READBACK_EN | (reg << 2));
     86
     87	ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
     88	if (ret)
     89		return ret;
     90
     91	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
     92	if (ret)
     93		return ret;
     94
     95	*value = be16_to_cpu(st->spi_msg);
     96
     97	return 0;
     98}
     99
    100static int ad5592r_gpio_read(struct ad5592r_state *st, u8 *value)
    101{
    102	int ret;
    103
    104	ret = ad5592r_reg_write(st, AD5592R_REG_GPIO_IN_EN,
    105				AD5592R_GPIO_READBACK_EN | st->gpio_in);
    106	if (ret)
    107		return ret;
    108
    109	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
    110	if (ret)
    111		return ret;
    112
    113	*value = (u8) be16_to_cpu(st->spi_msg);
    114
    115	return 0;
    116}
    117
    118static const struct ad5592r_rw_ops ad5592r_rw_ops = {
    119	.write_dac = ad5592r_write_dac,
    120	.read_adc = ad5592r_read_adc,
    121	.reg_write = ad5592r_reg_write,
    122	.reg_read = ad5592r_reg_read,
    123	.gpio_read = ad5592r_gpio_read,
    124};
    125
    126static int ad5592r_spi_probe(struct spi_device *spi)
    127{
    128	const struct spi_device_id *id = spi_get_device_id(spi);
    129
    130	return ad5592r_probe(&spi->dev, id->name, &ad5592r_rw_ops);
    131}
    132
    133static void ad5592r_spi_remove(struct spi_device *spi)
    134{
    135	ad5592r_remove(&spi->dev);
    136}
    137
    138static const struct spi_device_id ad5592r_spi_ids[] = {
    139	{ .name = "ad5592r", },
    140	{}
    141};
    142MODULE_DEVICE_TABLE(spi, ad5592r_spi_ids);
    143
    144static const struct of_device_id ad5592r_of_match[] = {
    145	{ .compatible = "adi,ad5592r", },
    146	{},
    147};
    148MODULE_DEVICE_TABLE(of, ad5592r_of_match);
    149
    150static const struct acpi_device_id ad5592r_acpi_match[] = {
    151	{"ADS5592", },
    152	{ },
    153};
    154MODULE_DEVICE_TABLE(acpi, ad5592r_acpi_match);
    155
    156static struct spi_driver ad5592r_spi_driver = {
    157	.driver = {
    158		.name = "ad5592r",
    159		.of_match_table = ad5592r_of_match,
    160		.acpi_match_table = ad5592r_acpi_match,
    161	},
    162	.probe = ad5592r_spi_probe,
    163	.remove = ad5592r_spi_remove,
    164	.id_table = ad5592r_spi_ids,
    165};
    166module_spi_driver(ad5592r_spi_driver);
    167
    168MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
    169MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
    170MODULE_LICENSE("GPL v2");
    171MODULE_IMPORT_NS(IIO_AD5592R);