simple_amplifier.c revision 1.2 
1/* $NetBSD: simple_amplifier.c,v 1.2 2021/01/27 03:10:21 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 2020 Jared McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__KERNEL_RCSID(0, "$NetBSD: simple_amplifier.c,v 1.2 2021/01/27 03:10:21 thorpej Exp $");
31
32#include <sys/param.h>
33#include <sys/bus.h>
34#include <sys/device.h>
35#include <sys/systm.h>
36#include <sys/sysctl.h>
37#include <sys/kmem.h>
38
39#include <dev/audio/audio_dai.h>
40
41#include <dev/fdt/fdtvar.h>
42
43struct simple_amplifier_softc {
44	device_t		sc_dev;
45	struct audio_dai_device	sc_dai;
46	struct fdtbus_gpio_pin	*sc_pin;
47	struct fdtbus_regulator	*sc_vcc;
48};
49
50static int	simple_amplifier_match(device_t, cfdata_t, void *);
51static void	simple_amplifier_attach(device_t, device_t, void *);
52
53static const struct device_compatible_entry compat_data[] = {
54	{ .compat = "simple-audio-amplifier" },
55	DEVICE_COMPAT_EOL
56};
57
58CFATTACH_DECL_NEW(simpleamp, sizeof(struct simple_amplifier_softc),
59	simple_amplifier_match, simple_amplifier_attach, NULL, NULL);
60
61static int
62simple_amplifier_open(void *priv, int flags)
63{
64	struct simple_amplifier_softc * const sc = priv;
65	int error;
66
67	if (sc->sc_pin != NULL)
68		fdtbus_gpio_write(sc->sc_pin, 1);
69
70	if (sc->sc_vcc != NULL) {
71		error = fdtbus_regulator_enable(sc->sc_vcc);
72		if (error != 0)
73			aprint_error_dev(sc->sc_dev, "couldn't enable power supply\n");
74	}
75
76	return 0;
77}
78
79static void
80simple_amplifier_close(void *priv)
81{
82	struct simple_amplifier_softc * const sc = priv;
83
84	if (sc->sc_pin != NULL)
85		fdtbus_gpio_write(sc->sc_pin, 0);
86
87	if (sc->sc_vcc != NULL)
88		(void)fdtbus_regulator_disable(sc->sc_vcc);
89}
90
91static const struct audio_hw_if simple_amplifier_hw_if = {
92	.open = simple_amplifier_open,
93	.close = simple_amplifier_close,
94};
95
96static audio_dai_tag_t
97simple_amplifier_dai_get_tag(device_t dev, const void *data, size_t len)
98{
99	struct simple_amplifier_softc * const sc = device_private(dev);
100
101	if (len != 4)
102		return NULL;
103
104	return &sc->sc_dai;
105}
106
107static struct fdtbus_dai_controller_func simple_amplifier_dai_funcs = {
108	.get_tag = simple_amplifier_dai_get_tag
109};
110
111static int
112simple_amplifier_match(device_t parent, cfdata_t cf, void *aux)
113{
114	struct fdt_attach_args * const faa = aux;
115
116	return of_compatible_match(faa->faa_phandle, compat_data);
117}
118
119static void
120simple_amplifier_attach(device_t parent, device_t self, void *aux)
121{
122	struct simple_amplifier_softc * const sc = device_private(self);
123	struct fdt_attach_args * const faa = aux;
124	const int phandle = faa->faa_phandle;
125
126	sc->sc_dev = self;
127	sc->sc_pin = fdtbus_gpio_acquire(phandle, "enable-gpios", GPIO_PIN_OUTPUT);
128	sc->sc_vcc = fdtbus_regulator_acquire(phandle, "VCC-supply");
129
130	aprint_naive("\n");
131	aprint_normal(": Simple Amplifier\n");
132
133	sc->sc_dai.dai_hw_if = &simple_amplifier_hw_if;
134	sc->sc_dai.dai_dev = self;
135	sc->sc_dai.dai_priv = sc;
136	fdtbus_register_dai_controller(self, phandle, &simple_amplifier_dai_funcs);
137}
138