adau1977-spi.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * ADAU1977/ADAU1978/ADAU1979 driver
 4 *
 5 * Copyright 2014 Analog Devices Inc.
 6 *  Author: Lars-Peter Clausen <lars@metafoo.de>
 7 */
 8
 9#include <linux/mod_devicetable.h>
10#include <linux/module.h>
11#include <linux/regmap.h>
12#include <linux/of.h>
13#include <linux/spi/spi.h>
14#include <sound/soc.h>
15
16#include "adau1977.h"
17
18static void adau1977_spi_switch_mode(struct device *dev)
19{
20	struct spi_device *spi = to_spi_device(dev);
21
22	/*
23	 * To get the device into SPI mode CLATCH has to be pulled low three
24	 * times.  Do this by issuing three dummy reads.
25	 */
26	spi_w8r8(spi, 0x00);
27	spi_w8r8(spi, 0x00);
28	spi_w8r8(spi, 0x00);
29}
30
31static int adau1977_spi_probe(struct spi_device *spi)
32{
33	const struct spi_device_id *id = spi_get_device_id(spi);
34	struct regmap_config config;
35
36	if (!id)
37		return -EINVAL;
38
39	config = adau1977_regmap_config;
40	config.val_bits = 8;
41	config.reg_bits = 16;
42	config.read_flag_mask = 0x1;
43
44	return adau1977_probe(&spi->dev,
45		devm_regmap_init_spi(spi, &config),
46		id->driver_data, adau1977_spi_switch_mode);
47}
48
49static const struct spi_device_id adau1977_spi_ids[] = {
50	{ "adau1977", ADAU1977 },
51	{ "adau1978", ADAU1978 },
52	{ "adau1979", ADAU1978 },
53	{ }
54};
55MODULE_DEVICE_TABLE(spi, adau1977_spi_ids);
56
57static const struct of_device_id adau1977_spi_of_match[] __maybe_unused = {
58        { .compatible = "adi,adau1977" },
59        { .compatible = "adi,adau1978" },
60        { .compatible = "adi,adau1979" },
61        { },
62};
63MODULE_DEVICE_TABLE(of, adau1977_spi_of_match);
64
65static struct spi_driver adau1977_spi_driver = {
66	.driver = {
67		.name = "adau1977",
68		.of_match_table = of_match_ptr(adau1977_spi_of_match),
69	},
70	.probe = adau1977_spi_probe,
71	.id_table = adau1977_spi_ids,
72};
73module_spi_driver(adau1977_spi_driver);
74
75MODULE_DESCRIPTION("ASoC ADAU1977/ADAU1978/ADAU1979 driver");
76MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
77MODULE_LICENSE("GPL");