ALSA: hda: Refactor display power management

The current HD-audio code manages the DRM audio power via too complex
redirections, and this seems even still unbalanced in a corner case as
Intel DRM CI has been intermittently reporting.  This patch is a big
surgery for addressing the complexity and the possible unbalance.

Basically the patch changes the display PM in the following ways:

- Both HD-audio controller and codec drivers call a single helper,
  snd_hdac_display_power().  (Formerly, the display power control from
  a codec was done indirectly via link_power bus ops.)

- snd_hdac_display_power() receives the codec address index.  For
  turning on/off from the controller, pass HDA_CODEC_IDX_CONTROLLER.

- snd_hdac_display_power() doesn't manage refcounts any longer, but
  keeps the power status in bitmap.  If any of controller or codecs is
  turned on, the function updates the DRM power state via get_power()
  or put_power().

Also this refactor allows us more cleanup:

- The link_power bus ops is dropped, so there is no longer indirect
  management, as mentioned in the above.

- hdac_device link_power_control flag is moved to hda_codec
  display_power_control flag, as it's only for HDA legacy.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106525
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/hda_codec.h

@@ -236,6 +236,7 @@ struct hda_codec {
 	/* misc flags */
 	unsigned int in_freeing:1; /* being released */
 	unsigned int registered:1; /* codec was registered */
+	unsigned int display_power_control:1; /* needs display power */
 	unsigned int spdif_status_reset :1; /* needs to toggle SPDIF for each
 					     * status change
 					     * (e.g. Realtek codecs)

include/sound/hda_component.h

@@ -5,10 +5,15 @@
 #define __SOUND_HDA_COMPONENT_H
 
 #include <drm/drm_audio_component.h>
+#include <sound/hdaudio.h>
+
+/* virtual idx for controller */
+#define HDA_CODEC_IDX_CONTROLLER	HDA_MAX_CODECS
 
 #ifdef CONFIG_SND_HDA_COMPONENT
 int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable);
-int snd_hdac_display_power(struct hdac_bus *bus, bool enable);
+int snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx,
+			   bool enable);
 int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid,
 			     int dev_id, int rate);
 int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid, int dev_id,
@@ -25,7 +30,8 @@ static inline int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
 {
 	return 0;
 }
-static inline int snd_hdac_display_power(struct hdac_bus *bus, bool enable)
+static inline int snd_hdac_display_power(struct hdac_bus *bus,
+					 unsigned int idx, bool enable)
 {
 	return 0;
 }

include/sound/hdaudio.h

@@ -79,7 +79,6 @@ struct hdac_device {
 
 	/* misc flags */
 	atomic_t in_pm;		/* suspend/resume being performed */
-	bool  link_power_control:1;
 
 	/* sysfs */
 	struct hdac_widget_tree *widgets;
@@ -237,8 +236,6 @@ struct hdac_bus_ops {
 	/* get a response from the last command */
 	int (*get_response)(struct hdac_bus *bus, unsigned int addr,
 			    unsigned int *res);
-	/* control the link power  */
-	int (*link_power)(struct hdac_bus *bus, bool enable);
 };
 
 /*
@@ -363,7 +360,8 @@ struct hdac_bus {
 
 	/* DRM component interface */
 	struct drm_audio_component *audio_component;
-	int drm_power_refcount;
+	long display_power_status;
+	bool display_power_active;
 
 	/* parameters required for enhanced capabilities */
 	int num_streams;
@@ -404,7 +402,6 @@ int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val);
 int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
 			      unsigned int *res);
 int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus);
-int snd_hdac_link_power(struct hdac_device *codec, bool enable);
 
 bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset);
 void snd_hdac_bus_stop_chip(struct hdac_bus *bus);