xref: /openbmc/linux/sound/soc/codecs/adau1372-spi.c (revision 39f555fb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for ADAU1372 codec
4  *
5  * Copyright 2016 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/spi/spi.h>
13 #include <sound/soc.h>
14 
15 #include "adau1372.h"
16 
17 static void adau1372_spi_switch_mode(struct device *dev)
18 {
19 	struct spi_device *spi = to_spi_device(dev);
20 
21 	/*
22 	 * To get the device into SPI mode CLATCH has to be pulled low three
23 	 * times.  Do this by issuing three dummy reads.
24 	 */
25 	spi_w8r8(spi, 0x00);
26 	spi_w8r8(spi, 0x00);
27 	spi_w8r8(spi, 0x00);
28 }
29 
30 static int adau1372_spi_probe(struct spi_device *spi)
31 {
32 	struct regmap_config config;
33 
34 	config = adau1372_regmap_config;
35 	config.read_flag_mask = 0x1;
36 
37 	return adau1372_probe(&spi->dev,
38 		devm_regmap_init_spi(spi, &config), adau1372_spi_switch_mode);
39 }
40 
41 static const struct spi_device_id adau1372_spi_id[] = {
42 	{ "adau1372", 0 },
43 	{ }
44 };
45 MODULE_DEVICE_TABLE(spi, adau1372_spi_id);
46 
47 static struct spi_driver adau1372_spi_driver = {
48 	.driver = {
49 		.name = "adau1372",
50 	},
51 	.probe = adau1372_spi_probe,
52 	.id_table = adau1372_spi_id,
53 };
54 module_spi_driver(adau1372_spi_driver);
55 
56 MODULE_DESCRIPTION("ASoC ADAU1372 CODEC SPI driver");
57 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
58 MODULE_LICENSE("GPL v2");
59