ASoC: Intel: avs: PCM power management

Merge series from Cezary Rojewski <cezary.rojewski@intel.com>:

Goal of the series is implementation of suspend/resume operations for a
PCM stream along with all the collaterals connected to the subject.

Start with splitting avs_dai_fe_hw_free() as ideally we would like to
reuse as much of existing code as possible but snd_pcm_lib_free_pages()
is not desired part of the function when speaking of suspend operation.

The actual implementation of suspend/resume() for component drivers
follows. For most scenarios, the PM flow is similar to standard
streaming one, except for the part where the position register are being
saved and the lack of PCM pages freeing. To reduce code duplication, all
avs_dai_suspend_XXX() and avs_dai_resume_XXX() functions reuse their
non-PM equivalents.
Order of operations is affected by the fact that path binding/unbinding
happens only in FE part of the stream.

Above essentially unlocks SX+streaming scenarios i.e.: power transitions
with an ongoing stream.

As some streams are allowed to run in low power state, support is
provided for S0iX state. The handlers check ACPI capabilities and the
number of active low-power paths before deciding between SX and S0iX
flows.

The last portion of the patchset is addition of power/clock gating
overrides. There is no single set of registers that ensures AudioDSP
firmware loads 100% of time on every single configuration. By having
them exposed, user can have the loading procedure behavior adjusted for
their configuration without having to recompile the kernel.

2 files changed, 6 insertions, 0 deletions

diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
index 78f1809a4ad6..a6872537724d 100644
--- a/include/sound/hdaudio.h
+++ b/include/sound/hdaudio.h
@@ -597,6 +597,7 @@ int snd_hdac_stream_get_spbmaxfifo(struct hdac_bus *bus,
 				   struct hdac_stream *azx_dev);
 void snd_hdac_stream_drsm_enable(struct hdac_bus *bus,
 				 bool enable, int index);
+int snd_hdac_stream_wait_drsm(struct hdac_stream *azx_dev);
 int snd_hdac_stream_set_dpibr(struct hdac_bus *bus,
 			      struct hdac_stream *azx_dev, u32 value);
 int snd_hdac_stream_set_lpib(struct hdac_stream *azx_dev, u32 value);
diff --git a/include/sound/hdaudio_ext.h b/include/sound/hdaudio_ext.h
index 90fd47e05370..68ab89211de2 100644
--- a/include/sound/hdaudio_ext.h
+++ b/include/sound/hdaudio_ext.h
@@ -51,6 +51,11 @@ struct hdac_ext_stream {
 	void __iomem *pphc_addr;
 	void __iomem *pplc_addr;
 
+	u32 pphcllpl;
+	u32 pphcllpu;
+	u32 pphcldpl;
+	u32 pphcldpu;
+
 	bool decoupled:1;
 	bool link_locked:1;
 	bool link_prepared;