102 Commits (347d1c01956d567c18afef0cc253eb235cafacd8)

Author	SHA1	Message	Date
Richard Purdie	2b97eabc09	[ALSA] ASoC: dynamic audio power management (DAPM) ... This patch adds Dynamic Audio Power Management (DAPM) to ASoC. Dynamic Audio Power Management (DAPM) is designed to allow portable and handheld Linux devices to use the minimum amount of power within the audio subsystem at all times. It is independent of other kernel PM and as such, can easily co-exist with the other PM systems. DAPM is also completely transparent to all user space applications as all power switching is done within the ASoC core. No code changes or recompiling are required for user space applications. DAPM makes power switching decisions based upon any audio stream (capture/playback) activity and audio mixer settings within the device. DAPM spans the whole machine. It covers power control within the entire audio subsystem, this includes internal codec power blocks and machine level power systems. There are 4 power domains within DAPM:- 1. Codec domain - VREF, VMID (core codec and audio power) Usually controlled at codec probe/remove and suspend/resume, although can be set at stream time if power is not needed for sidetone, etc. 2. Platform/Machine domain - physically connected inputs and outputs Is platform/machine and user action specific, is configured by the machine driver and responds to asynchronous events e.g when HP are inserted 3. Path domain - audio subsystem signal paths Automatically set when mixer and mux settings are changed by the user. e.g. alsamixer, amixer. 4. Stream domain - DAC's and ADC's. Enabled and disabled when stream playback/capture is started and stopped respectively. e.g. aplay, arecord. All DAPM power switching decisions are made automatically by consulting an audio routing map of the whole machine. This map is specific to each machine and consists of the interconnections between every audio component (including internal codec components). Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Liam Girdwood <liam.girdwood@wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>	18 years ago
Frank Mandarino	db2a416556	[ALSA] ASoC: core code ... This patch is the core of ASoC functionality. The ASoC core is designed to provide the following features :- o Codec independence. Allows reuse of codec drivers on other platforms and machines. o Platform driver code reuse. Reuse of platform specific audio DMA and DAI drivers on different machines. o Easy I2S/PCM digital audio interface configuration between codec and SoC. Each SoC interface and codec registers their audio interface capabilities with the core at initialisation. The capabilities are subsequently matched and configured at run time for best power and performance when the application hw params are known. o Machine specific controls/operations: Allow machines to add controls and operations to the audio subsystem. e.g. volume control for speaker amp. To achieve all this, ASoC splits an embedded audio system into 3 components :- 1. Codec driver: The codec driver is platform independent and contains audio controls, audio interface capabilities, codec dapm and codec IO functions. 2. Platform driver: The platform driver contains the audio dma engine and audio interface drivers (e.g. I2S, AC97, PCM) for that platform. 3. Machine driver: The machine driver handles any machine specific controls and audio events. i.e. turning on an amp at start of playback. Signed-off-by: Frank Mandarino <fmandarino@endrelia.com> Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Liam Girdwood <liam.Girdwood@wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>	18 years ago