mirror of https://gitee.com/openkylin/linux.git
cb53c626e1
Added CONFIG_SND_HDA_POWER_SAVE kconfig. It's an experimental option to achieve an aggressive power-saving. With this option, the driver will turn on/off the power of each codec and controller chip dynamically on demand. The patch introduces a new module option 'power_save'. It specifies the second of time-out for automatic power-down. As default, it's 10 seconds. Setting 0 means to suppress the power-saving feature. The codec may have analog-input loopbacks, which are usually represented by mixer elements such as 'Mic Playback Switch' or 'CD Playback Switch'. When these are on, we cannot turn off the mixer and the codec chip has to be kept on. For bookkeeping these states, a new codec-callback is introduced. For the bus-controller side, a new callback pm_notify is introduced, which can be used to turn on/off the contoller appropriately. Note that this power-saving might cause slight click-noise at power-on/off. Also, it might take some time to wake up the codec, and might even drop some tones at the very beginning. This seems to be the side-effect of turning off the controller chip. This turn-off of the controller can be disabled by undefining HDA_POWER_SAVE_RESET_CONTOLLER in hda_intel.c. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz> |
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| .. | ||
| aoa | ||
| arm | ||
| core | ||
| drivers | ||
| i2c | ||
| isa | ||
| mips | ||
| oss | ||
| parisc | ||
| pci | ||
| pcmcia | ||
| ppc | ||
| sh | ||
| soc | ||
| sparc | ||
| spi | ||
| synth | ||
| usb | ||
| Kconfig | ||
| Makefile | ||
| ac97_bus.c | ||
| last.c | ||
| sound_core.c | ||
| sound_firmware.c | ||