cx18-audio.c

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/*
 *  cx18 audio-related functions
 *
 *  Derived from ivtv-audio.c
 *
 *  Copyright (C) 2007  Hans Verkuil <[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.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA
 */

#include "cx18-driver.h"
#include "cx18-io.h"
#include "cx18-cards.h"
#include "cx18-audio.h"

#define CX18_AUDIO_ENABLE    0xc72014
#define CX18_AI1_MUX_MASK    0x30
#define CX18_AI1_MUX_I2S1    0x00
#define CX18_AI1_MUX_I2S2    0x10
#define CX18_AI1_MUX_843_I2S 0x20

/* Selects the audio input and output according to the current
   settings. */
int cx18_audio_set_io(struct cx18 *cx)
{
    const struct cx18_card_audio_input *in;
    u32 u, v;
    int err;

    /* Determine which input to use */
    if (test_bit(CX18_F_I_RADIO_USER, &cx->i_flags))
        in = &cx->card->radio_input;
    else
        in = &cx->card->audio_inputs[cx->audio_input];

    /* handle muxer chips */
    v4l2_subdev_call(cx->sd_extmux, audio, s_routing,
             (u32) in->muxer_input, 0, 0);

    err = cx18_call_hw_err(cx, cx->card->hw_audio_ctrl,
                   audio, s_routing, in->audio_input, 0, 0);
    if (err)
        return err;

    /* FIXME - this internal mux should be abstracted to a subdev */
    u = cx18_read_reg(cx, CX18_AUDIO_ENABLE);
    v = u & ~CX18_AI1_MUX_MASK;
    switch (in->audio_input) {
    case CX18_AV_AUDIO_SERIAL1:
        v |= CX18_AI1_MUX_I2S1;
        break;
    case CX18_AV_AUDIO_SERIAL2:
        v |= CX18_AI1_MUX_I2S2;
        break;
    default:
        v |= CX18_AI1_MUX_843_I2S;
        break;
    }
    if (v == u) {
        /* force a toggle of some AI1 MUX control bits */
        u &= ~CX18_AI1_MUX_MASK;
        switch (in->audio_input) {
        case CX18_AV_AUDIO_SERIAL1:
            u |= CX18_AI1_MUX_843_I2S;
            break;
        case CX18_AV_AUDIO_SERIAL2:
            u |= CX18_AI1_MUX_843_I2S;
            break;
        default:
            u |= CX18_AI1_MUX_I2S1;
            break;
        }
        cx18_write_reg_expect(cx, u | 0xb00, CX18_AUDIO_ENABLE,
                      u, CX18_AI1_MUX_MASK);
    }
    cx18_write_reg_expect(cx, v | 0xb00, CX18_AUDIO_ENABLE,
                  v, CX18_AI1_MUX_MASK);
    return 0;
}