tree 2a96c35b59641cb3cf898333398388b0155af77e
parent bfb7802a06ac1855096a3f248822e8f943e6574d
author Vinod Koul <vinod.koul@intel.com> 1463023733 +0530
committer Mark Brown <broonie@kernel.org> 1463136180 +0100

ALSA: hdac: add link pm and ref counting

The HDA links can be switched off when not is use, similarly
command DMA can be stopped as well. This calls for a reference
counting mechanism on the link by it's users to manage the link
power. The DMA can be turned off when all links are off

For this we add two APIs
	snd_hdac_ext_bus_link_get
	snd_hdac_ext_bus_link_put

They help users to turn up/down link and manage the DMA as well

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>