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 int ad5592r_spi_remove(struct spi_device *spi)
134{
135	return 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");