1 ============================================== 1 =================================================== 2 Dynamic Audio Power Management for Portable De 2 Dynamic Audio Power Management for Portable Devices 3 ============================================== 3 =================================================== 4 4 5 Description 5 Description 6 =========== 6 =========== 7 7 8 Dynamic Audio Power Management (DAPM) is desig 8 Dynamic Audio Power Management (DAPM) is designed to allow portable 9 Linux devices to use the minimum amount of pow 9 Linux devices to use the minimum amount of power within the audio 10 subsystem at all times. It is independent of o !! 10 subsystem at all times. It is independent of other kernel PM and as 11 management frameworks and, as such, can easily !! 11 such, can easily co-exist with the other PM systems. 12 12 13 DAPM is also completely transparent to all use 13 DAPM is also completely transparent to all user space applications as 14 all power switching is done within the ASoC co 14 all power switching is done within the ASoC core. No code changes or 15 recompiling are required for user space applic 15 recompiling are required for user space applications. DAPM makes power 16 switching decisions based upon any audio strea 16 switching decisions based upon any audio stream (capture/playback) 17 activity and audio mixer settings within the d 17 activity and audio mixer settings within the device. 18 18 19 DAPM is based on two basic elements, called wi !! 19 DAPM spans the whole machine. It covers power control within the entire >> 20 audio subsystem, this includes internal codec power blocks and machine >> 21 level power systems. 20 22 21 * a **widget** is every part of the audio har !! 23 There are 4 power domains within DAPM 22 software when in use and disabled to save p << 23 * a **route** is an interconnection between w << 24 can flow from one widget to the other << 25 << 26 All DAPM power switching decisions are made au << 27 audio routing graph. This graph is specific to << 28 the whole sound card, so some DAPM routes conn << 29 different components (e.g. the LINE OUT pin of << 30 an amplifier). << 31 << 32 The graph for the STM32MP1-DK1 sound card is s << 33 << 34 .. kernel-figure:: dapm-graph.svg << 35 :alt: Example DAPM graph << 36 :align: center << 37 << 38 DAPM power domains << 39 ================== << 40 << 41 There are 4 power domains within DAPM: << 42 24 43 Codec bias domain 25 Codec bias domain 44 VREF, VMID (core codec and audio power) 26 VREF, VMID (core codec and audio power) 45 27 46 Usually controlled at codec probe/remove 28 Usually controlled at codec probe/remove and suspend/resume, although 47 can be set at stream time if power is no 29 can be set at stream time if power is not needed for sidetone, etc. 48 30 49 Platform/Machine domain 31 Platform/Machine domain 50 physically connected inputs and outputs 32 physically connected inputs and outputs 51 33 52 Is platform/machine and user action spec 34 Is platform/machine and user action specific, is configured by the 53 machine driver and responds to asynchron 35 machine driver and responds to asynchronous events e.g when HP 54 are inserted 36 are inserted 55 37 56 Path domain 38 Path domain 57 audio subsystem signal paths 39 audio subsystem signal paths 58 40 59 Automatically set when mixer and mux set 41 Automatically set when mixer and mux settings are changed by the user. 60 e.g. alsamixer, amixer. 42 e.g. alsamixer, amixer. 61 43 62 Stream domain 44 Stream domain 63 DACs and ADCs. 45 DACs and ADCs. 64 46 65 Enabled and disabled when stream playbac 47 Enabled and disabled when stream playback/capture is started and 66 stopped respectively. e.g. aplay, arecor 48 stopped respectively. e.g. aplay, arecord. 67 49 >> 50 All DAPM power switching decisions are made automatically by consulting an audio >> 51 routing map of the whole machine. This map is specific to each machine and >> 52 consists of the interconnections between every audio component (including >> 53 internal codec components). All audio components that effect power are called >> 54 widgets hereafter. >> 55 68 56 69 DAPM Widgets 57 DAPM Widgets 70 ============ 58 ============ 71 59 72 Audio DAPM widgets fall into a number of types !! 60 Audio DAPM widgets fall into a number of types:- 73 61 74 Mixer 62 Mixer 75 Mixes several analog signals into a si 63 Mixes several analog signals into a single analog signal. 76 Mux 64 Mux 77 An analog switch that outputs only one 65 An analog switch that outputs only one of many inputs. 78 PGA 66 PGA 79 A programmable gain amplifier or atten 67 A programmable gain amplifier or attenuation widget. 80 ADC 68 ADC 81 Analog to Digital Converter 69 Analog to Digital Converter 82 DAC 70 DAC 83 Digital to Analog Converter 71 Digital to Analog Converter 84 Switch 72 Switch 85 An analog switch 73 An analog switch 86 Input 74 Input 87 A codec input pin 75 A codec input pin 88 Output 76 Output 89 A codec output pin 77 A codec output pin 90 Headphone 78 Headphone 91 Headphone (and optional Jack) 79 Headphone (and optional Jack) 92 Mic 80 Mic 93 Mic (and optional Jack) 81 Mic (and optional Jack) 94 Line 82 Line 95 Line Input/Output (and optional Jack) 83 Line Input/Output (and optional Jack) 96 Speaker 84 Speaker 97 Speaker 85 Speaker 98 Supply 86 Supply 99 Power or clock supply widget used by o 87 Power or clock supply widget used by other widgets. 100 Regulator 88 Regulator 101 External regulator that supplies power 89 External regulator that supplies power to audio components. 102 Clock 90 Clock 103 External clock that supplies clock to 91 External clock that supplies clock to audio components. 104 AIF IN 92 AIF IN 105 Audio Interface Input (with TDM slot m 93 Audio Interface Input (with TDM slot mask). 106 AIF OUT 94 AIF OUT 107 Audio Interface Output (with TDM slot 95 Audio Interface Output (with TDM slot mask). 108 Siggen 96 Siggen 109 Signal Generator. 97 Signal Generator. 110 DAI IN 98 DAI IN 111 Digital Audio Interface Input. 99 Digital Audio Interface Input. 112 DAI OUT 100 DAI OUT 113 Digital Audio Interface Output. 101 Digital Audio Interface Output. 114 DAI Link 102 DAI Link 115 DAI Link between two DAI structures 103 DAI Link between two DAI structures 116 Pre 104 Pre 117 Special PRE widget (exec before all ot 105 Special PRE widget (exec before all others) 118 Post 106 Post 119 Special POST widget (exec after all ot 107 Special POST widget (exec after all others) 120 Buffer << 121 Inter widget audio data buffer within << 122 Scheduler << 123 DSP internal scheduler that schedules << 124 work. << 125 Effect << 126 Widget that performs an audio processi << 127 SRC << 128 Sample Rate Converter within DSP or CO << 129 ASRC << 130 Asynchronous Sample Rate Converter wit << 131 Encoder << 132 Widget that encodes audio data from on << 133 usually more compressed format. << 134 Decoder << 135 Widget that decodes audio data from a << 136 uncompressed format like PCM. << 137 << 138 108 139 (Widgets are defined in include/sound/soc-dapm 109 (Widgets are defined in include/sound/soc-dapm.h) 140 110 141 Widgets can be added to the sound card by any 111 Widgets can be added to the sound card by any of the component driver types. 142 There are convenience macros defined in soc-da 112 There are convenience macros defined in soc-dapm.h that can be used to quickly 143 build a list of widgets of the codecs and mach 113 build a list of widgets of the codecs and machines DAPM widgets. 144 114 145 Most widgets have a name, register, shift and 115 Most widgets have a name, register, shift and invert. Some widgets have extra 146 parameters for stream name and kcontrols. 116 parameters for stream name and kcontrols. 147 117 148 118 149 Stream Domain Widgets 119 Stream Domain Widgets 150 --------------------- 120 --------------------- 151 121 152 Stream Widgets relate to the stream power doma 122 Stream Widgets relate to the stream power domain and only consist of ADCs 153 (analog to digital converters), DACs (digital 123 (analog to digital converters), DACs (digital to analog converters), 154 AIF IN and AIF OUT. 124 AIF IN and AIF OUT. 155 125 156 Stream widgets have the following format: !! 126 Stream widgets have the following format:- 157 :: 127 :: 158 128 159 SND_SOC_DAPM_DAC(name, stream name, reg, shi 129 SND_SOC_DAPM_DAC(name, stream name, reg, shift, invert), 160 SND_SOC_DAPM_AIF_IN(name, stream, slot, reg, 130 SND_SOC_DAPM_AIF_IN(name, stream, slot, reg, shift, invert) 161 131 162 NOTE: the stream name must match the correspon 132 NOTE: the stream name must match the corresponding stream name in your codec 163 snd_soc_dai_driver. !! 133 snd_soc_codec_dai. 164 134 165 e.g. stream widgets for HiFi playback and capt 135 e.g. stream widgets for HiFi playback and capture 166 :: 136 :: 167 137 168 SND_SOC_DAPM_DAC("HiFi DAC", "HiFi Playback" 138 SND_SOC_DAPM_DAC("HiFi DAC", "HiFi Playback", REG, 3, 1), 169 SND_SOC_DAPM_ADC("HiFi ADC", "HiFi Capture", 139 SND_SOC_DAPM_ADC("HiFi ADC", "HiFi Capture", REG, 2, 1), 170 140 171 e.g. stream widgets for AIF 141 e.g. stream widgets for AIF 172 :: 142 :: 173 143 174 SND_SOC_DAPM_AIF_IN("AIF1RX", "AIF1 Playback 144 SND_SOC_DAPM_AIF_IN("AIF1RX", "AIF1 Playback", 0, SND_SOC_NOPM, 0, 0), 175 SND_SOC_DAPM_AIF_OUT("AIF1TX", "AIF1 Capture 145 SND_SOC_DAPM_AIF_OUT("AIF1TX", "AIF1 Capture", 0, SND_SOC_NOPM, 0, 0), 176 146 177 147 178 Path Domain Widgets 148 Path Domain Widgets 179 ------------------- 149 ------------------- 180 150 181 Path domain widgets have a ability to control 151 Path domain widgets have a ability to control or affect the audio signal or 182 audio paths within the audio subsystem. They h !! 152 audio paths within the audio subsystem. They have the following form:- 183 :: 153 :: 184 154 185 SND_SOC_DAPM_PGA(name, reg, shift, invert, c 155 SND_SOC_DAPM_PGA(name, reg, shift, invert, controls, num_controls) 186 156 187 Any widget kcontrols can be set using the cont 157 Any widget kcontrols can be set using the controls and num_controls members. 188 158 189 e.g. Mixer widget (the kcontrols are declared 159 e.g. Mixer widget (the kcontrols are declared first) 190 :: 160 :: 191 161 192 /* Output Mixer */ 162 /* Output Mixer */ 193 static const snd_kcontrol_new_t wm8731_outpu 163 static const snd_kcontrol_new_t wm8731_output_mixer_controls[] = { 194 SOC_DAPM_SINGLE("Line Bypass Switch", WM8731 164 SOC_DAPM_SINGLE("Line Bypass Switch", WM8731_APANA, 3, 1, 0), 195 SOC_DAPM_SINGLE("Mic Sidetone Switch", WM873 165 SOC_DAPM_SINGLE("Mic Sidetone Switch", WM8731_APANA, 5, 1, 0), 196 SOC_DAPM_SINGLE("HiFi Playback Switch", WM87 166 SOC_DAPM_SINGLE("HiFi Playback Switch", WM8731_APANA, 4, 1, 0), 197 }; 167 }; 198 168 199 SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PW 169 SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PWR, 4, 1, wm8731_output_mixer_controls, 200 ARRAY_SIZE(wm8731_output_mixer_control 170 ARRAY_SIZE(wm8731_output_mixer_controls)), 201 171 202 If you don't want the mixer elements prefixed 172 If you don't want the mixer elements prefixed with the name of the mixer widget, 203 you can use SND_SOC_DAPM_MIXER_NAMED_CTL inste 173 you can use SND_SOC_DAPM_MIXER_NAMED_CTL instead. the parameters are the same 204 as for SND_SOC_DAPM_MIXER. 174 as for SND_SOC_DAPM_MIXER. 205 175 206 176 207 Machine domain Widgets 177 Machine domain Widgets 208 ---------------------- 178 ---------------------- 209 179 210 Machine widgets are different from codec widge 180 Machine widgets are different from codec widgets in that they don't have a 211 codec register bit associated with them. A mac 181 codec register bit associated with them. A machine widget is assigned to each 212 machine audio component (non codec or DSP) tha 182 machine audio component (non codec or DSP) that can be independently 213 powered. e.g. 183 powered. e.g. 214 184 215 * Speaker Amp 185 * Speaker Amp 216 * Microphone Bias 186 * Microphone Bias 217 * Jack connectors 187 * Jack connectors 218 188 219 A machine widget can have an optional call bac 189 A machine widget can have an optional call back. 220 190 221 e.g. Jack connector widget for an external Mic 191 e.g. Jack connector widget for an external Mic that enables Mic Bias 222 when the Mic is inserted:: !! 192 when the Mic is inserted:-:: 223 193 224 static int spitz_mic_bias(struct snd_soc_dap 194 static int spitz_mic_bias(struct snd_soc_dapm_widget* w, int event) 225 { 195 { 226 gpio_set_value(SPITZ_GPIO_MIC_BIAS, SN 196 gpio_set_value(SPITZ_GPIO_MIC_BIAS, SND_SOC_DAPM_EVENT_ON(event)); 227 return 0; 197 return 0; 228 } 198 } 229 199 230 SND_SOC_DAPM_MIC("Mic Jack", spitz_mic_bias) 200 SND_SOC_DAPM_MIC("Mic Jack", spitz_mic_bias), 231 201 232 202 233 Codec (BIAS) Domain 203 Codec (BIAS) Domain 234 ------------------- 204 ------------------- 235 205 236 The codec bias power domain has no widgets and !! 206 The codec bias power domain has no widgets and is handled by the codecs DAPM 237 event handler. This handler is called when the 207 event handler. This handler is called when the codec powerstate is changed wrt 238 to any stream event or by kernel PM events. 208 to any stream event or by kernel PM events. 239 209 240 210 241 Virtual Widgets 211 Virtual Widgets 242 --------------- 212 --------------- 243 213 244 Sometimes widgets exist in the codec or machin !! 214 Sometimes widgets exist in the codec or machine audio map that don't have any 245 corresponding soft power control. In this case 215 corresponding soft power control. In this case it is necessary to create 246 a virtual widget - a widget with no control bi 216 a virtual widget - a widget with no control bits e.g. 247 :: 217 :: 248 218 249 SND_SOC_DAPM_MIXER("AC97 Mixer", SND_SOC_NOP !! 219 SND_SOC_DAPM_MIXER("AC97 Mixer", SND_SOC_DAPM_NOPM, 0, 0, NULL, 0), 250 << 251 This can be used to merge two signal paths tog << 252 220 253 Registering DAPM controls !! 221 This can be used to merge to signal paths together in software. 254 ========================= << 255 222 256 In many cases the DAPM widgets are implemented !! 223 After all the widgets have been defined, they can then be added to the DAPM 257 const struct snd_soc_dapm_widget`` array in a !! 224 subsystem individually with a call to snd_soc_dapm_new_control(). 258 declared via the ``dapm_widgets`` and ``num_da << 259 ``struct snd_soc_component_driver``. << 260 << 261 Similarly, routes connecting them are implemen << 262 const struct snd_soc_dapm_route`` array and de << 263 ``dapm_routes`` and ``num_dapm_routes`` fields << 264 << 265 With the above declared, the driver registrati << 266 populating them:: << 267 << 268 static const struct snd_soc_dapm_widget wm20 << 269 SND_SOC_DAPM_OUTPUT("SPKN"), << 270 SND_SOC_DAPM_OUTPUT("SPKP"), << 271 ... << 272 }; << 273 << 274 /* Target, Path, Source */ << 275 static const struct snd_soc_dapm_route wm200 << 276 { "SPKN", NULL, "ANC Engine" }, << 277 { "SPKP", NULL, "ANC Engine" }, << 278 ... << 279 }; << 280 << 281 static const struct snd_soc_component_driver << 282 ... << 283 .dapm_widgets = wm2000_dapm_ << 284 .num_dapm_widgets = ARRAY_SIZE(w << 285 .dapm_routes = wm2000_audio << 286 .num_dapm_routes = ARRAY_SIZE(w << 287 ... << 288 }; << 289 << 290 In more complex cases the list of DAPM widgets << 291 known at probe time. This happens for example << 292 different models having a different set of fea << 293 separate widgets and routes arrays implementin << 294 can be registered programmatically by calling << 295 and snd_soc_dapm_add_routes(). << 296 225 297 226 298 Codec/DSP Widget Interconnections 227 Codec/DSP Widget Interconnections 299 ================================= 228 ================================= 300 229 301 Widgets are connected to each other within the 230 Widgets are connected to each other within the codec, platform and machine by 302 audio paths (called interconnections). Each in 231 audio paths (called interconnections). Each interconnection must be defined in 303 order to create a graph of all audio paths bet !! 232 order to create a map of all audio paths between widgets. 304 233 305 This is easiest with a diagram of the codec or 234 This is easiest with a diagram of the codec or DSP (and schematic of the machine 306 audio system), as it requires joining widgets 235 audio system), as it requires joining widgets together via their audio signal 307 paths. 236 paths. 308 237 309 For example the WM8731 output mixer (wm8731.c) !! 238 e.g., from the WM8731 output mixer (wm8731.c) >> 239 >> 240 The WM8731 output mixer has 3 inputs (sources) 310 241 311 1. Line Bypass Input 242 1. Line Bypass Input 312 2. DAC (HiFi playback) 243 2. DAC (HiFi playback) 313 3. Mic Sidetone Input 244 3. Mic Sidetone Input 314 245 315 Each input in this example has a kcontrol asso !! 246 Each input in this example has a kcontrol associated with it (defined in example 316 the example above) and is connected to the out !! 247 above) and is connected to the output mixer via its kcontrol name. We can now 317 name. We can now connect the destination widge !! 248 connect the destination widget (wrt audio signal) with its source widgets. 318 source widgets. :: !! 249 :: 319 250 320 /* output mixer */ 251 /* output mixer */ 321 {"Output Mixer", "Line Bypass Switch", 252 {"Output Mixer", "Line Bypass Switch", "Line Input"}, 322 {"Output Mixer", "HiFi Playback Switch 253 {"Output Mixer", "HiFi Playback Switch", "DAC"}, 323 {"Output Mixer", "Mic Sidetone Switch" 254 {"Output Mixer", "Mic Sidetone Switch", "Mic Bias"}, 324 255 325 So we have: !! 256 So we have :- 326 257 327 * Destination Widget <=== Path Name <=== Sour 258 * Destination Widget <=== Path Name <=== Source Widget, or 328 * Sink, Path, Source, or 259 * Sink, Path, Source, or 329 * ``Output Mixer`` is connected to the ``DAC`` 260 * ``Output Mixer`` is connected to the ``DAC`` via the ``HiFi Playback Switch``. 330 261 331 When there is no path name connecting widgets 262 When there is no path name connecting widgets (e.g. a direct connection) we 332 pass NULL for the path name. 263 pass NULL for the path name. 333 264 334 Interconnections are created with a call to:: !! 265 Interconnections are created with a call to:- >> 266 :: 335 267 336 snd_soc_dapm_connect_input(codec, sink, path 268 snd_soc_dapm_connect_input(codec, sink, path, source); 337 269 338 Finally, snd_soc_dapm_new_widgets() must be ca !! 270 Finally, snd_soc_dapm_new_widgets(codec) must be called after all widgets and 339 interconnections have been registered with the 271 interconnections have been registered with the core. This causes the core to 340 scan the codec and machine so that the interna 272 scan the codec and machine so that the internal DAPM state matches the 341 physical state of the machine. 273 physical state of the machine. 342 274 343 275 344 Machine Widget Interconnections 276 Machine Widget Interconnections 345 ------------------------------- 277 ------------------------------- 346 Machine widget interconnections are created in 278 Machine widget interconnections are created in the same way as codec ones and 347 directly connect the codec pins to machine lev 279 directly connect the codec pins to machine level widgets. 348 280 349 e.g. connects the speaker out codec pins to th 281 e.g. connects the speaker out codec pins to the internal speaker. 350 :: 282 :: 351 283 352 /* ext speaker connected to codec pins 284 /* ext speaker connected to codec pins LOUT2, ROUT2 */ 353 {"Ext Spk", NULL , "ROUT2"}, 285 {"Ext Spk", NULL , "ROUT2"}, 354 {"Ext Spk", NULL , "LOUT2"}, 286 {"Ext Spk", NULL , "LOUT2"}, 355 287 356 This allows the DAPM to power on and off pins 288 This allows the DAPM to power on and off pins that are connected (and in use) 357 and pins that are NC respectively. 289 and pins that are NC respectively. 358 290 359 291 360 Endpoint Widgets 292 Endpoint Widgets 361 ================ 293 ================ 362 An endpoint is a start or end point (widget) o 294 An endpoint is a start or end point (widget) of an audio signal within the 363 machine and includes the codec. e.g. 295 machine and includes the codec. e.g. 364 296 365 * Headphone Jack 297 * Headphone Jack 366 * Internal Speaker 298 * Internal Speaker 367 * Internal Mic 299 * Internal Mic 368 * Mic Jack 300 * Mic Jack 369 * Codec Pins 301 * Codec Pins 370 302 371 Endpoints are added to the DAPM graph so that 303 Endpoints are added to the DAPM graph so that their usage can be determined in 372 order to save power. e.g. NC codecs pins will 304 order to save power. e.g. NC codecs pins will be switched OFF, unconnected 373 jacks can also be switched OFF. 305 jacks can also be switched OFF. 374 306 375 307 376 DAPM Widget Events 308 DAPM Widget Events 377 ================== 309 ================== 378 310 379 Widgets needing to implement a more complex be !! 311 Some widgets can register their interest with the DAPM core in PM events. 380 can set a custom "event handler" by setting a !! 312 e.g. A Speaker with an amplifier registers a widget so the amplifier can be 381 is a power supply needing to enable a GPIO:: !! 313 powered only when the spk is in use. >> 314 :: 382 315 383 static int sof_es8316_speaker_power_event(st !! 316 /* turn speaker amplifier on/off depending on use */ 384 stru !! 317 static int corgi_amp_event(struct snd_soc_dapm_widget *w, int event) 385 { 318 { 386 if (SND_SOC_DAPM_EVENT_ON(event)) !! 319 gpio_set_value(CORGI_GPIO_APM_ON, SND_SOC_DAPM_EVENT_ON(event)); 387 gpiod_set_value_cansleep(gpio_ !! 320 return 0; 388 else << 389 gpiod_set_value_cansleep(gpio_ << 390 << 391 return 0; << 392 } 321 } 393 322 394 static const struct snd_soc_dapm_widget st_w !! 323 /* corgi machine dapm widgets */ 395 ... !! 324 static const struct snd_soc_dapm_widget wm8731_dapm_widgets = 396 SND_SOC_DAPM_SUPPLY("Speaker Power", S !! 325 SND_SOC_DAPM_SPK("Ext Spk", corgi_amp_event); 397 sof_es8316_speaker << 398 SND_SOC_DAPM_PRE_P << 399 }; << 400 326 401 See soc-dapm.h for all other widgets that supp !! 327 Please see soc-dapm.h for all other widgets that support events. 402 328 403 329 404 Event types 330 Event types 405 ----------- 331 ----------- 406 332 407 The following event types are supported by eve !! 333 The following event types are supported by event widgets. >> 334 :: 408 335 409 /* dapm event types */ 336 /* dapm event types */ 410 #define SND_SOC_DAPM_PRE_PMU 0x1 !! 337 #define SND_SOC_DAPM_PRE_PMU 0x1 /* before widget power up */ 411 #define SND_SOC_DAPM_POST_PMU 0x2 !! 338 #define SND_SOC_DAPM_POST_PMU 0x2 /* after widget power up */ 412 #define SND_SOC_DAPM_PRE_PMD 0x4 !! 339 #define SND_SOC_DAPM_PRE_PMD 0x4 /* before widget power down */ 413 #define SND_SOC_DAPM_POST_PMD 0x8 !! 340 #define SND_SOC_DAPM_POST_PMD 0x8 /* after widget power down */ 414 #define SND_SOC_DAPM_PRE_REG 0x10 !! 341 #define SND_SOC_DAPM_PRE_REG 0x10 /* before audio path setup */ 415 #define SND_SOC_DAPM_POST_REG 0x20 !! 342 #define SND_SOC_DAPM_POST_REG 0x20 /* after audio path setup */ 416 #define SND_SOC_DAPM_WILL_PMU 0x40 << 417 #define SND_SOC_DAPM_WILL_PMD 0x80 << 418 #define SND_SOC_DAPM_PRE_POST_PMD (SND_S << 419 #define SND_SOC_DAPM_PRE_POST_PMU (SND_S <<
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