1 files changed, 152 insertions, 0 deletions

diff --git a/firmware/export/ak4376.h b/firmware/export/ak4376.h
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+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2021 Aidan MacDonald
+ *
+ * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#ifndef __AK4376_H__
+#define __AK4376_H__
+
+#define AUDIOHW_CAPS (FILTER_ROLL_OFF_CAP|POWER_MODE_CAP)
+#define AUDIOHW_HAVE_SHORT2_ROLL_OFF
+
+#define AK4376_MIN_VOLUME (-890)
+#define AK4376_MAX_VOLUME 150
+
+AUDIOHW_SETTING(VOLUME, "dB", 1, 5, AK4376_MIN_VOLUME, AK4376_MAX_VOLUME, -200)
+AUDIOHW_SETTING(FILTER_ROLL_OFF, "", 0, 1, 0, 3, 0)
+AUDIOHW_SETTING(POWER_MODE, "", 0, 1, 0, 1, 0)
+
+/* Register addresses */
+#define AK4376_REG_PWR1         0x00
+#define AK4376_REG_PWR2         0x01
+#define AK4376_REG_PWR3         0x02
+#define AK4376_REG_PWR4         0x03
+#define AK4376_REG_OUTPUT_MODE  0x04
+#define AK4376_REG_CLOCK_MODE   0x05
+#define AK4376_REG_FILTER       0x06
+#define AK4376_REG_MIXER        0x07
+#define AK4376_REG_LCH_VOLUME   0x0b
+#define AK4376_REG_RCH_VOLUME   0x0c
+#define AK4376_REG_AMP_VOLUME   0x0d
+#define AK4376_REG_PLL_CLK_SRC  0x0e
+#define AK4376_REG_PLL_REF_DIV1 0x0f
+#define AK4376_REG_PLL_REF_DIV2 0x10
+#define AK4376_REG_PLL_FB_DIV1  0x11
+#define AK4376_REG_PLL_FB_DIV2  0x12
+#define AK4376_REG_DAC_CLK_SRC  0x13
+#define AK4376_REG_DAC_CLK_DIV  0x14
+#define AK4376_REG_AUDIO_IF_FMT 0x15
+#define AK4376_REG_CHIP_ID      0x21
+#define AK4376_REG_MODE_CTRL    0x24
+#define AK4376_REG_ADJUST1      0x26
+#define AK4376_REG_ADJUST2      0x2a
+#define AK4376_NUM_REGS         0x2b
+
+/* Mixer controls, simply OR them together.
+ * LCH    = add LCH signal to output
+ * RCH    = add RCH signal to output
+ * HALF   = multiply output by 1/2
+ * INVERT = invert the output after everything else
+ */
+#define AK4376_MIX_MUTE   0
+#define AK4376_MIX_LCH    1
+#define AK4376_MIX_RCH    2
+#define AK4376_MIX_HALF   4
+#define AK4376_MIX_INVERT 8
+
+/* Min/max digital volumes in units of dB/10 */
+#define AK4376_DIG_VOLUME_MIN (-120)
+#define AK4376_DIG_VOLUME_MAX 30
+#define AK4376_DIG_VOLUME_STEP 5
+#define AK4376_DIG_VOLUME_MUTE (AK4376_DIG_VOLUME_MIN - 1)
+
+/* Min/max headphone amp volumes in units of dB/10 */
+#define AK4376_AMP_VOLUME_MIN (-200)
+#define AK4376_AMP_VOLUME_MAX 60
+#define AK4376_AMP_VOLUME_STEP 20
+#define AK4376_AMP_VOLUME_MUTE (AK4376_AMP_VOLUME_MIN - 1)
+
+/* Digital filters */
+#define AK4376_FILTER_SHARP       0
+#define AK4376_FILTER_SLOW        1
+#define AK4376_FILTER_SHORT_SHARP 2
+#define AK4376_FILTER_SHORT_SLOW  3
+
+/* Frequency selection */
+#define AK4376_FS_8   0
+#define AK4376_FS_11  1
+#define AK4376_FS_12  2
+#define AK4376_FS_16  4
+#define AK4376_FS_22  5
+#define AK4376_FS_24  6
+#define AK4376_FS_32  8
+#define AK4376_FS_44  9
+#define AK4376_FS_48  10
+#define AK4376_FS_64  12
+#define AK4376_FS_88  13
+#define AK4376_FS_96  14
+#define AK4376_FS_176 17
+#define AK4376_FS_192 18
+
+/* Functions to power on / off the DAC which should be called from
+ * the target's audiohw_init() / audiohw_close() implementation.
+ */
+extern void ak4376_init(void);
+extern void ak4376_close(void);
+
+/* Register read/write. Cached to avoid redundant reads/writes. */
+extern void ak4376_write(int reg, int value);
+extern int  ak4376_read(int reg);
+
+/* Target-specific function to set the PDN pin level. */
+extern void ak4376_set_pdn_pin(int level);
+
+/* Target-specific function to control the external master clock frequency.
+ * This is called by the ak4376's audiohw implementation when switching to
+ * or from a frequency that is configured to use this clock source.
+ *
+ * - hw_freq is the new sample rate -- one of the HW_FREQ_XX constants.
+ * - enabled is true if clock should be output, false if not.
+ *
+ * The return value is the master clock rate as a multiple of the sampling
+ * frequency. The allowed multiples depend on the sampling frequency, shown
+ * in the table below.
+ *
+ * +-----------+------------------------+
+ * | frequency | master clock rate      |
+ * +-----------+------------------------+
+ * |   8 -  24 | 256fs / 512fs / 1024fs |
+ * |  32 -  48 | 256fs / 512fs          |
+ * |  64 -  96 | 256fs                  |
+ * | 128 - 192 | 128fs                  |
+ * +-----------+------------------------+
+ *
+ * For example, at 48 KHz you could return either 256 or 512 depending on
+ * the rate you decided to actually use.
+ *
+ * You need to return a valid master multiplier for supported frequencies
+ * even when enabled = false, since the driver needs to know the multiplier
+ * _before_ enabling the clock.
+ *
+ * For unsupported frequencies you don't need to return a valid master
+ * multiplier, because the DAC doesn't need the return value in such cases.
+ */
+extern int ak4376_set_mclk_freq(int hw_freq, bool enabled);
+
+#endif /* __AK4376_H__ */