diff options
Diffstat (limited to 'firmware/drivers/audio')
-rw-r--r-- | firmware/drivers/audio/ak4376.c | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/firmware/drivers/audio/ak4376.c b/firmware/drivers/audio/ak4376.c new file mode 100644 index 0000000000..494bbabfa4 --- /dev/null +++ b/firmware/drivers/audio/ak4376.c | |||
@@ -0,0 +1,274 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id$ | ||
9 | * | ||
10 | * Copyright (C) 2021 Aidan MacDonald | ||
11 | * | ||
12 | * This program is free software; you can redistribute it and/or | ||
13 | * modify it under the terms of the GNU General Public License | ||
14 | * as published by the Free Software Foundation; either version 2 | ||
15 | * of the License, or (at your option) any later version. | ||
16 | * | ||
17 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
18 | * KIND, either express or implied. | ||
19 | * | ||
20 | ****************************************************************************/ | ||
21 | |||
22 | #include "audiohw.h" | ||
23 | #include "sound.h" | ||
24 | #include "panic.h" | ||
25 | #include "pcm_sampr.h" | ||
26 | #include "pcm_sw_volume.h" | ||
27 | #include "system.h" | ||
28 | #include "i2c-async.h" | ||
29 | |||
30 | #ifndef HAVE_SW_VOLUME_CONTROL | ||
31 | # error "AK4376 requires HAVE_SW_VOLUME_CONTROL!" | ||
32 | #endif | ||
33 | |||
34 | /* NOTE: At present, only the FiiO M3K uses this driver so the handling of | ||
35 | * the clock / audio interface is limited to I2S slave, 16-bit samples, with | ||
36 | * DAC master clock provided directly on the MCLK input pin, fitting the | ||
37 | * clock setup of the M3K. | ||
38 | * | ||
39 | * Feel free to expand upon this if another target ever needs this driver. | ||
40 | */ | ||
41 | |||
42 | /* Converts HW_FREQ_XX constants to register values */ | ||
43 | static const int ak4376_fsel_to_hw[] = { | ||
44 | HW_HAVE_192_(AK4376_FS_192,) | ||
45 | HW_HAVE_176_(AK4376_FS_176,) | ||
46 | HW_HAVE_96_(AK4376_FS_96,) | ||
47 | HW_HAVE_88_(AK4376_FS_88,) | ||
48 | HW_HAVE_64_(AK4376_FS_64,) | ||
49 | HW_HAVE_48_(AK4376_FS_48,) | ||
50 | HW_HAVE_44_(AK4376_FS_44,) | ||
51 | HW_HAVE_32_(AK4376_FS_32,) | ||
52 | HW_HAVE_24_(AK4376_FS_24,) | ||
53 | HW_HAVE_22_(AK4376_FS_22,) | ||
54 | HW_HAVE_16_(AK4376_FS_16,) | ||
55 | HW_HAVE_12_(AK4376_FS_12,) | ||
56 | HW_HAVE_11_(AK4376_FS_11,) | ||
57 | HW_HAVE_8_(AK4376_FS_8,) | ||
58 | }; | ||
59 | |||
60 | static struct ak4376 { | ||
61 | int fsel; | ||
62 | int low_mode; | ||
63 | int regs[AK4376_NUM_REGS]; | ||
64 | } ak4376; | ||
65 | |||
66 | void ak4376_init(void) | ||
67 | { | ||
68 | /* Initialize DAC state */ | ||
69 | ak4376.fsel = HW_FREQ_48; | ||
70 | ak4376.low_mode = 0; | ||
71 | for(int i = 0; i < AK4376_NUM_REGS; ++i) | ||
72 | ak4376.regs[i] = -1; | ||
73 | |||
74 | /* Initial reset after power-on */ | ||
75 | ak4376_set_pdn_pin(0); | ||
76 | mdelay(1); | ||
77 | ak4376_set_pdn_pin(1); | ||
78 | mdelay(1); | ||
79 | |||
80 | static const int init_config[] = { | ||
81 | /* Ensure HPRHZ, HPLHZ are 0 */ | ||
82 | AK4376_REG_OUTPUT_MODE, 0x00, | ||
83 | /* Mute all volume controls */ | ||
84 | AK4376_REG_MIXER, 0x00, | ||
85 | AK4376_REG_LCH_VOLUME, 0x80, | ||
86 | AK4376_REG_RCH_VOLUME, 0x00, | ||
87 | AK4376_REG_AMP_VOLUME, 0x00, | ||
88 | /* Clock source = MCLK, divider = 1 */ | ||
89 | AK4376_REG_DAC_CLK_SRC, 0x00, | ||
90 | AK4376_REG_DAC_CLK_DIV, 0x00, | ||
91 | /* I2S slave mode, 16-bit samples */ | ||
92 | AK4376_REG_AUDIO_IF_FMT, 0x03, | ||
93 | /* Recommended by datasheet */ | ||
94 | AK4376_REG_ADJUST1, 0x20, | ||
95 | AK4376_REG_ADJUST2, 0x05, | ||
96 | /* Power controls */ | ||
97 | AK4376_REG_PWR2, 0x33, | ||
98 | AK4376_REG_PWR3, 0x01, | ||
99 | AK4376_REG_PWR4, 0x03, | ||
100 | }; | ||
101 | |||
102 | /* Write initial configuration prior to power-up */ | ||
103 | for(size_t i = 0; i < ARRAYLEN(init_config); i += 2) | ||
104 | ak4376_write(init_config[i], init_config[i+1]); | ||
105 | |||
106 | /* Initial frequency setting, also handles DAC/amp power-up */ | ||
107 | audiohw_set_frequency(HW_FREQ_48); | ||
108 | } | ||
109 | |||
110 | void ak4376_close(void) | ||
111 | { | ||
112 | /* Shut off power */ | ||
113 | ak4376_write(AK4376_REG_PWR3, 0x00); | ||
114 | ak4376_write(AK4376_REG_PWR4, 0x00); | ||
115 | ak4376_write(AK4376_REG_PWR2, 0x00); | ||
116 | |||
117 | /* PDN pin low */ | ||
118 | ak4376_set_pdn_pin(0); | ||
119 | } | ||
120 | |||
121 | void ak4376_write(int reg, int value) | ||
122 | { | ||
123 | /* Ensure value is sensible and differs from the last set value */ | ||
124 | if((value & 0xff) == value && ak4376.regs[reg] != value) { | ||
125 | int r = i2c_reg_write1(AK4376_BUS, AK4376_ADDR, reg, value); | ||
126 | if(r == I2C_STATUS_OK) | ||
127 | ak4376.regs[reg] = value; | ||
128 | else | ||
129 | ak4376.regs[reg] = -1; | ||
130 | } | ||
131 | } | ||
132 | |||
133 | int ak4376_read(int reg) | ||
134 | { | ||
135 | /* Only read from I2C if we don't already know the value */ | ||
136 | if(ak4376.regs[reg] < 0) | ||
137 | ak4376.regs[reg] = i2c_reg_read1(AK4376_BUS, AK4376_ADDR, reg); | ||
138 | |||
139 | return ak4376.regs[reg]; | ||
140 | } | ||
141 | |||
142 | static int round_step_up(int x, int step) | ||
143 | { | ||
144 | int rem = x % step; | ||
145 | if(rem > 0) | ||
146 | rem -= step; | ||
147 | return x - rem; | ||
148 | } | ||
149 | |||
150 | static void calc_volumes(int vol, int* mix, int* dig, int* sw) | ||
151 | { | ||
152 | /* Mixer can divide by 2, which gives an extra -6 dB adjustment */ | ||
153 | if(vol < AK4376_DIG_VOLUME_MIN) { | ||
154 | *mix |= AK4376_MIX_HALF; | ||
155 | vol += 60; | ||
156 | } | ||
157 | |||
158 | *dig = round_step_up(vol, AK4376_DIG_VOLUME_STEP); | ||
159 | *dig = MIN(*dig, AK4376_DIG_VOLUME_MAX); | ||
160 | *dig = MAX(*dig, AK4376_DIG_VOLUME_MIN); | ||
161 | vol -= *dig; | ||
162 | |||
163 | /* Seems that this is the allowable range for software volume */ | ||
164 | *sw = MIN(vol, 60); | ||
165 | *sw = MAX(*sw, -730); | ||
166 | vol -= *sw; | ||
167 | } | ||
168 | |||
169 | static int dig_vol_to_hw(int vol) | ||
170 | { | ||
171 | if(vol < AK4376_DIG_VOLUME_MIN) return 0; | ||
172 | if(vol > AK4376_DIG_VOLUME_MAX) return 31; | ||
173 | return (vol - AK4376_DIG_VOLUME_MIN) / AK4376_DIG_VOLUME_STEP + 1; | ||
174 | } | ||
175 | |||
176 | static int amp_vol_to_hw(int vol) | ||
177 | { | ||
178 | if(vol < AK4376_AMP_VOLUME_MIN) return 0; | ||
179 | if(vol > AK4376_AMP_VOLUME_MAX) return 14; | ||
180 | return (vol - AK4376_AMP_VOLUME_MIN) / AK4376_AMP_VOLUME_STEP + 1; | ||
181 | } | ||
182 | |||
183 | void audiohw_set_volume(int vol_l, int vol_r) | ||
184 | { | ||
185 | int amp; | ||
186 | int mix_l = AK4376_MIX_LCH, dig_l, sw_l; | ||
187 | int mix_r = AK4376_MIX_RCH, dig_r, sw_r; | ||
188 | |||
189 | if(vol_l <= AK4376_MIN_VOLUME && vol_r <= AK4376_MIN_VOLUME) { | ||
190 | /* Special case for full mute */ | ||
191 | amp = AK4376_AMP_VOLUME_MUTE; | ||
192 | dig_l = dig_r = AK4376_DIG_VOLUME_MUTE; | ||
193 | sw_l = sw_r = PCM_MUTE_LEVEL; | ||
194 | } else { | ||
195 | /* Amp is a mono control -- calculate based on the loudest channel. | ||
196 | * The quieter channel then gets reduced more by digital controls. */ | ||
197 | amp = round_step_up(MAX(vol_l, vol_r), AK4376_AMP_VOLUME_STEP); | ||
198 | amp = MIN(amp, AK4376_AMP_VOLUME_MAX); | ||
199 | amp = MAX(amp, AK4376_AMP_VOLUME_MIN); | ||
200 | |||
201 | /* Other controls are stereo */ | ||
202 | calc_volumes(vol_l - amp, &mix_l, &dig_l, &sw_l); | ||
203 | calc_volumes(vol_r - amp, &mix_r, &dig_r, &sw_r); | ||
204 | } | ||
205 | |||
206 | ak4376_write(AK4376_REG_MIXER, (mix_l & 0xf) | ((mix_r & 0xf) << 4)); | ||
207 | ak4376_write(AK4376_REG_LCH_VOLUME, dig_vol_to_hw(dig_l) | (1 << 7)); | ||
208 | ak4376_write(AK4376_REG_RCH_VOLUME, dig_vol_to_hw(dig_r)); | ||
209 | ak4376_write(AK4376_REG_AMP_VOLUME, amp_vol_to_hw(amp)); | ||
210 | pcm_set_master_volume(sw_l, sw_r); | ||
211 | } | ||
212 | |||
213 | void audiohw_set_filter_roll_off(int val) | ||
214 | { | ||
215 | int reg = ak4376_read(AK4376_REG_FILTER); | ||
216 | reg &= ~0xc0; | ||
217 | reg |= (val & 3) << 6; | ||
218 | ak4376_write(AK4376_REG_FILTER, reg); | ||
219 | } | ||
220 | |||
221 | void audiohw_set_frequency(int fsel) | ||
222 | { | ||
223 | /* Determine master clock multiplier */ | ||
224 | int mult = ak4376_set_mclk_freq(fsel, false); | ||
225 | |||
226 | /* Calculate clock mode for frequency. Multipliers of 32/64 are only | ||
227 | * for rates >= 256 KHz which are not supported by Rockbox, so they | ||
228 | * are commented out -- but they're in the correct place. */ | ||
229 | int clock_mode = ak4376_fsel_to_hw[fsel]; | ||
230 | switch(mult) { | ||
231 | /* case 32: */ | ||
232 | case 256: | ||
233 | break; | ||
234 | /* case 64: */ | ||
235 | case 512: | ||
236 | clock_mode |= 0x20; | ||
237 | break; | ||
238 | case 1024: | ||
239 | clock_mode |= 0x40; | ||
240 | break; | ||
241 | case 128: | ||
242 | clock_mode |= 0x60; | ||
243 | break; | ||
244 | default: | ||
245 | panicf("ak4376: bad master clock multiple %d", mult); | ||
246 | return; | ||
247 | } | ||
248 | |||
249 | /* Handle the DSMLP bit in the MODE_CTRL register */ | ||
250 | int mode_ctrl = 0x00; | ||
251 | if(ak4376.low_mode || hw_freq_sampr[fsel] <= SAMPR_12) | ||
252 | mode_ctrl |= 0x40; | ||
253 | |||
254 | /* Program the new settings */ | ||
255 | ak4376_write(AK4376_REG_CLOCK_MODE, clock_mode); | ||
256 | ak4376_write(AK4376_REG_MODE_CTRL, mode_ctrl); | ||
257 | ak4376_write(AK4376_REG_PWR3, ak4376.low_mode ? 0x11 : 0x01); | ||
258 | |||
259 | /* Enable the master clock */ | ||
260 | ak4376_set_mclk_freq(fsel, true); | ||
261 | |||
262 | /* Remember the frequency */ | ||
263 | ak4376.fsel = fsel; | ||
264 | } | ||
265 | |||
266 | void audiohw_set_power_mode(int mode) | ||
267 | { | ||
268 | /* This is handled via audiohw_set_frequency() since changing LPMODE | ||
269 | * bit requires power-down/power-up & changing other bits as well */ | ||
270 | if(ak4376.low_mode != mode) { | ||
271 | ak4376.low_mode = mode; | ||
272 | audiohw_set_frequency(ak4376.fsel); | ||
273 | } | ||
274 | } | ||