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ALSA: hdac: ext: add wait for codec to respond after link reset

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As per HDA spec section 4.3 - Codec Discovery, the software shall wait
for atleast 521usec for codec to respond after link reset.
With the multi-link capability each link is turned ON/OFF individually.
Link controller drives reset signal when it is turned ON.

Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Rakesh Ughreja 2018-06-01 22:54:00 -05:00 committed by Takashi Iwai
parent e1df9317cb
commit f8a7fe1aea
1 changed files with 9 additions and 0 deletions
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9
sound/hda/ext/hdac_ext_controller.c
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@ -271,6 +271,15 @@ int snd_hdac_ext_bus_link_get(struct hdac_bus *bus,
}
ret = snd_hdac_ext_bus_link_power_up(link);
/*
* wait for 521usec for codec to report status
* HDA spec section 4.3 - Codec Discovery
*/
udelay(521);
bus->codec_mask = snd_hdac_chip_readw(bus, STATESTS);
dev_dbg(bus->dev, "codec_mask = 0x%lx\n", bus->codec_mask);
snd_hdac_chip_writew(bus, STATESTS, bus->codec_mask);
}
mutex_unlock(&bus->lock);