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>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/sound/hda_codec.h b/include/sound/hda_codec.h
index 0d98bb9068b1..7fa48b100936 100644
--- a/include/sound/hda_codec.h
+++ b/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)