rockbox/firmware/drivers/audio/wm8751.c

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Driver for WM8751 audio codec
 *
 * Based on code from the ipodlinux project - http://ipodlinux.org/
 * Adapted for Rockbox in December 2005
 *
 * Original file: linux/arch/armnommu/mach-ipod/audio.c
 *
 * Copyright (c) 2003-2005 Bernard Leach (leachbj@bouncycastle.org)
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include "kernel.h"
#include "wmcodec.h"
#include "i2s.h"
#include "audio.h"
#include "sound.h"

/* Flags used in combination with settings */

/* use zero crossing to reduce clicks during volume changes */
#define LOUT1_BITS      (LOUT1_LO1ZC)
/* latch left volume first then update left+right together */
#define ROUT1_BITS      (ROUT1_RO1ZC | ROUT1_RO1VU)
#define LOUT2_BITS      (LOUT2_LO2ZC)
#define ROUT2_BITS      (ROUT2_RO2ZC | ROUT2_RO2VU)
/* We use linear bass control with 200 Hz cutoff */
#define BASSCTRL_BITS   (BASSCTRL_BC)
/* We use linear treble control with 4 kHz cutoff */
#define TREBCTRL_BITS   (TREBCTRL_TC)

/* convert tenth of dB volume (-730..60) to master volume register value */
int tenthdb2master(int db)
{
    /* +6 to -73dB 1dB steps (plus mute == 80levels) 7bits */
    /* 1111111 ==  +6dB  (0x7f)                            */
    /* 1111001 ==   0dB  (0x79)                            */
    /* 0110000 == -73dB  (0x30)                            */
    /* 0101111..0000000 == mute  (<= 0x2f)                 */
    if (db < VOLUME_MIN)
        return 0x0;
    else
        return (db / 10) + 73 + 0x30;
}

/* convert tenth of dB volume (-780..0) to mixer volume register value */
int tenthdb2mixer(int db)
{
    (void)db;
    return 0;
}

static int tone_tenthdb2hw(int value)
{
    /* -6.0db..+0db..+9.0db step 1.5db - translate -60..+0..+90 step 15
        to 10..6..0 step -1.
    */
    value = 10 - (value + 60) / 15;

    if (value == 6)
        value = 0xf; /* 0db -> off */

    return value;
}

void audiohw_reset(void);

/* Silently enable / disable audio output */
void audiohw_enable_output(bool enable)
{
    if (enable) 
    {
        /* reset the I2S controller into known state */
        i2s_reset();

        /*
         * 1. Switch on power supplies.
         *    By default the WM87551L is in Standby Mode, the DAC is
         *    digitally muted and the Audio Interface, Line outputs
         *    and Headphone outputs are all OFF (DACMU = 1 Power
         *    Management registers 1 and 2 are all zeros).
         */
        wmcodec_write(RESET, RESET_RESET);    /*Reset*/

         /* 2. Enable Vmid and VREF. */
        wmcodec_write(PWRMGMT1, PWRMGMT1_VREF | PWRMGMT1_VMIDSEL_500K);

        /* From app notes: allow Vref to stabilize to reduce clicks */
        sleep(HZ/2);

         /* 3. Enable DACs as required. */
        wmcodec_write(PWRMGMT2, PWRMGMT2_DACL | PWRMGMT2_DACR);
    
         /* 4. Enable line and / or headphone output buffers as required. */
        wmcodec_write(PWRMGMT2, PWRMGMT2_DACL | PWRMGMT2_DACR |
                      PWRMGMT2_LOUT1 | PWRMGMT2_ROUT1 | PWRMGMT2_LOUT2 |
                      PWRMGMT2_ROUT2);
    
        /* BCLKINV=0(Dont invert BCLK) MS=1(Enable Master) LRSWAP=0 LRP=0 */
        /* IWL=00(16 bit) FORMAT=10(I2S format) */
        wmcodec_write(AINTFCE, AINTFCE_MS | AINTFCE_WL_16 |
                      AINTFCE_FORMAT_I2S);

        /* Keep it quiet */
        wmcodec_write(LOUT1, LOUT1_BITS | OUTPUT_MUTED);
        wmcodec_write(ROUT1, ROUT1_BITS | OUTPUT_MUTED);
        wmcodec_write(LOUT2, LOUT2_BITS | OUTPUT_MUTED);
        wmcodec_write(ROUT2, ROUT2_BITS | OUTPUT_MUTED);

        wmcodec_write(LEFTMIX1, LEFTMIX1_LD2LO | LEFTMIX1_LI2LO_DEFAULT);
        wmcodec_write(RIGHTMIX2, RIGHTMIX2_RD2RO | RIGHTMIX2_RI2RO_DEFAULT);
    }

    audiohw_mute(!enable);
}

int audiohw_set_master_vol(int vol_l, int vol_r)
{
    /* +6 to -73dB 1dB steps (plus mute == 80levels) 7bits */
    /* 1111111 ==  +6dB                                    */
    /* 1111001 ==   0dB                                    */
    /* 0110000 == -73dB                                    */
    /* 0101111 == mute (0x2f)                              */

    wmcodec_write(LOUT1, LOUT1_BITS | LOUT1_LOUT1VOL(vol_l));
    wmcodec_write(ROUT1, ROUT1_BITS | ROUT1_ROUT1VOL(vol_r));
    return 0;
}

int audiohw_set_lineout_vol(int vol_l, int vol_r)
{
    wmcodec_write(LOUT2, LOUT2_BITS | LOUT2_LOUT2VOL(vol_l));
    wmcodec_write(ROUT2, ROUT2_BITS | ROUT2_ROUT2VOL(vol_r));
    return 0;
}

int audiohw_set_mixer_vol(int channel1, int channel2)
{
    (void)channel1;
    (void)channel2;

    return 0;
}

void audiohw_set_bass(int value)
{
    wmcodec_write(BASSCTRL, BASSCTRL_BITS |
        BASSCTRL_BASS(tone_tenthdb2hw(value)));
}

void audiohw_set_treble(int value)
{
    wmcodec_write(TREBCTRL, TREBCTRL_BITS |
        TREBCTRL_TREB(tone_tenthdb2hw(value)));
}

int audiohw_mute(int mute)
{
    /* Mute:   Set DACMU = 1 to soft-mute the audio DACs. */
    /* Unmute: Set DACMU = 0 to soft-un-mute the audio DACs. */
    wmcodec_write(DACCTRL, mute ? DACCTRL_DACMU : 0);
    return 0;
}

/* Nice shutdown of WM8751 codec */
void audiohw_close(void)
{
    /* 1. Set DACMU = 1 to soft-mute the audio DACs. */
    audiohw_mute(true);

    /* 2. Disable all output buffers. */
    wmcodec_write(PWRMGMT2, 0x0);

    /* 3. Switch off the power supplies. */
    wmcodec_write(PWRMGMT1, 0x0);
}

/* Note: Disable output before calling this function */
void audiohw_set_frequency(int fsel)
{
    wmcodec_write(CLOCKING, fsel);
}