cs5535audio_olpc.c

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/*
 * OLPC XO-1 additional sound features
 *
 * Copyright © 2006  Jaya Kumar <[email protected]>
 * Copyright © 2007-2008  Andres Salomon <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */
#include <sound/core.h>
#include <sound/info.h>
#include <sound/control.h>
#include <sound/ac97_codec.h>
#include <linux/gpio.h>

#include <asm/olpc.h>
#include "cs5535audio.h"

#define DRV_NAME "cs5535audio-olpc"

/*
 * OLPC has an additional feature on top of the regular AD1888 codec features.
 * It has an Analog Input mode that is switched into (after disabling the
 * High Pass Filter) via GPIO.  It is supported on B2 and later models.
 */
void olpc_analog_input(struct snd_ac97 *ac97, int on)
{
    int err;

    if (!machine_is_olpc())
        return;

    /* update the High Pass Filter (via AC97_AD_TEST2) */
    err = snd_ac97_update_bits(ac97, AC97_AD_TEST2,
            1 << AC97_AD_HPFD_SHIFT, on << AC97_AD_HPFD_SHIFT);
    if (err < 0) {
        snd_printk(KERN_ERR "setting High Pass Filter - %d\n", err);
        return;
    }

    /* set Analog Input through GPIO */
    gpio_set_value(OLPC_GPIO_MIC_AC, on);
}

/*
 * OLPC XO-1's V_REFOUT is a mic bias enable.
 */
void olpc_mic_bias(struct snd_ac97 *ac97, int on)
{
    int err;

    if (!machine_is_olpc())
        return;

    on = on ? 0 : 1;
    err = snd_ac97_update_bits(ac97, AC97_AD_MISC,
            1 << AC97_AD_VREFD_SHIFT, on << AC97_AD_VREFD_SHIFT);
    if (err < 0)
        snd_printk(KERN_ERR "setting MIC Bias - %d\n", err);
}

static int olpc_dc_info(struct snd_kcontrol *kctl,
        struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 1;
    return 0;
}

static int olpc_dc_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
{
    v->value.integer.value[0] = gpio_get_value(OLPC_GPIO_MIC_AC);
    return 0;
}

static int olpc_dc_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
{
    struct cs5535audio *cs5535au = snd_kcontrol_chip(kctl);

    olpc_analog_input(cs5535au->ac97, v->value.integer.value[0]);
    return 1;
}

static int olpc_mic_info(struct snd_kcontrol *kctl,
        struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 1;
    return 0;
}

static int olpc_mic_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
{
    struct cs5535audio *cs5535au = snd_kcontrol_chip(kctl);
    struct snd_ac97 *ac97 = cs5535au->ac97;
    int i;

    i = (snd_ac97_read(ac97, AC97_AD_MISC) >> AC97_AD_VREFD_SHIFT) & 0x1;
    v->value.integer.value[0] = i ? 0 : 1;
    return 0;
}

static int olpc_mic_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
{
    struct cs5535audio *cs5535au = snd_kcontrol_chip(kctl);

    olpc_mic_bias(cs5535au->ac97, v->value.integer.value[0]);
    return 1;
}

static struct snd_kcontrol_new olpc_cs5535audio_ctls[] __devinitdata = {
{
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "DC Mode Enable",
    .info = olpc_dc_info,
    .get = olpc_dc_get,
    .put = olpc_dc_put,
    .private_value = 0,
},
{
    .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
    .name = "MIC Bias Enable",
    .info = olpc_mic_info,
    .get = olpc_mic_get,
    .put = olpc_mic_put,
    .private_value = 0,
},
};

void __devinit olpc_prequirks(struct snd_card *card,
        struct snd_ac97_template *ac97)
{
    if (!machine_is_olpc())
        return;

    /* invert EAPD if on an OLPC B3 or higher */
    if (olpc_board_at_least(olpc_board_pre(0xb3)))
        ac97->scaps |= AC97_SCAP_INV_EAPD;
}

int __devinit olpc_quirks(struct snd_card *card, struct snd_ac97 *ac97)
{
    struct snd_ctl_elem_id elem;
    int i, err;

    if (!machine_is_olpc())
        return 0;

    if (gpio_request(OLPC_GPIO_MIC_AC, DRV_NAME)) {
        printk(KERN_ERR DRV_NAME ": unable to allocate MIC GPIO\n");
        return -EIO;
    }
    gpio_direction_output(OLPC_GPIO_MIC_AC, 0);

    /* drop the original AD1888 HPF control */
    memset(&elem, 0, sizeof(elem));
    elem.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
    strncpy(elem.name, "High Pass Filter Enable", sizeof(elem.name));
    snd_ctl_remove_id(card, &elem);

    /* drop the original V_REFOUT control */
    memset(&elem, 0, sizeof(elem));
    elem.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
    strncpy(elem.name, "V_REFOUT Enable", sizeof(elem.name));
    snd_ctl_remove_id(card, &elem);

    /* add the OLPC-specific controls */
    for (i = 0; i < ARRAY_SIZE(olpc_cs5535audio_ctls); i++) {
        err = snd_ctl_add(card, snd_ctl_new1(&olpc_cs5535audio_ctls[i],
                ac97->private_data));
        if (err < 0) {
            gpio_free(OLPC_GPIO_MIC_AC);
            return err;
        }
    }

    /* turn off the mic by default */
    olpc_mic_bias(ac97, 0);
    return 0;
}

void __devexit olpc_quirks_cleanup(void)
{
    gpio_free(OLPC_GPIO_MIC_AC);
}