simple_amplifier.c

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/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2020 Oleksandr Tymoshenko <gonzo@FreeBSD.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/rman.h>
#include <sys/resource.h>
#include <machine/bus.h>
 
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
 
#include <dev/extres/regulator/regulator.h>
#include <dev/gpio/gpiobusvar.h>
 
#include "opt_snd.h"
#include <dev/sound/pcm/sound.h>
#include <dev/sound/fdt/audio_dai.h>
#include "audio_dai_if.h"
 
static struct ofw_compat_data compat_data[] = {
        { "simple-audio-amplifier",     1},
        { NULL,                         0}
};
 
struct simple_amp_softc {
        device_t        dev;
        regulator_t     supply_vcc;
        gpio_pin_t      gpio_enable;
        bool            gpio_is_valid;
};
 
static int simple_amp_probe(device_t dev);
static int simple_amp_attach(device_t dev);
static int simple_amp_detach(device_t dev);
 
static int
simple_amp_probe(device_t dev)
{
        if (!ofw_bus_status_okay(dev))
                return (ENXIO);
 
        if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
                return (ENXIO);
 
        device_set_desc(dev, "Simple Amplifier");
        return (BUS_PROBE_DEFAULT);
}
 
static int
simple_amp_attach(device_t dev)
{
        struct simple_amp_softc *sc;
        phandle_t node;
        int error;
 
        sc = device_get_softc(dev);
        sc->dev = dev;
        node = ofw_bus_get_node(dev);
 
        error = gpio_pin_get_by_ofw_property(dev, node,
            "enable-gpios", &sc->gpio_enable);
        if (error != 0)
                sc->gpio_is_valid = false;
        else
                sc->gpio_is_valid = true;
 
        error = regulator_get_by_ofw_property(dev, 0, "VCC-supply",
            &sc->supply_vcc);
        if (error != 0)
                device_printf(dev, "no VCC supply");
 
        OF_device_register_xref(OF_xref_from_node(node), dev);
 
        return (0);
}
 
static int
simple_amp_detach(device_t dev)
{
 
        return (0);
}
 
static int
simple_amp_dai_init(device_t dev, uint32_t format)
{
 
        return (0);
}
 
static int
simple_amp_dai_trigger(device_t dev, int go, int pcm_dir)
{
        struct simple_amp_softc *sc;
        int error;
 
        if ((pcm_dir != PCMDIR_PLAY) && (pcm_dir != PCMDIR_REC))
                return (EINVAL);
 
        sc = device_get_softc(dev);
        error = 0;
        switch (go) {
        case PCMTRIG_START:
                if (sc->supply_vcc != NULL) {
                        error = regulator_enable(sc->supply_vcc);
                        if (error != 0) {
                                device_printf(sc->dev,
                                    "could not enable 'VCC' regulator\n");
                                break;
                        }
                }
 
                if (sc->gpio_is_valid) {
                        error = gpio_pin_set_active(sc->gpio_enable, 1);
                        if (error != 0) {
                                device_printf(sc->dev,
                                    "could not set 'gpio-enable' gpio\n");
                                break;
                        }
                }
 
                break;
 
        case PCMTRIG_STOP:
        case PCMTRIG_ABORT:
                if (sc->gpio_is_valid) {
                        error = gpio_pin_set_active(sc->gpio_enable, 0);
                        if (error != 0) {
                                device_printf(sc->dev,
                                    "could not clear 'gpio-enable' gpio\n");
                                break;
                        }
                }
 
                if (sc->supply_vcc != NULL) {
                        error = regulator_disable(sc->supply_vcc);
                        if (error != 0) {
                                device_printf(sc->dev,
                                    "could not disable 'VCC' regulator\n");
                                break;
                        }
                }
 
                break;
        }
 
        return (error);
}
 
static device_method_t simple_amp_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         simple_amp_probe),
        DEVMETHOD(device_attach,        simple_amp_attach),
        DEVMETHOD(device_detach,        simple_amp_detach),
 
        DEVMETHOD(audio_dai_init,       simple_amp_dai_init),
        DEVMETHOD(audio_dai_trigger,    simple_amp_dai_trigger),
 
        DEVMETHOD_END
};
 
static driver_t simple_amp_driver = {
        "simpleamp",
        simple_amp_methods,
        sizeof(struct simple_amp_softc),
};
 
static devclass_t simple_amp_devclass;
 
DRIVER_MODULE(simple_amp, simplebus, simple_amp_driver, simple_amp_devclass, 0, 0);
SIMPLEBUS_PNP_INFO(compat_data);