ALSA: hda/hdmi: let new platforms assign the pcm slot dynamically

If the platform set the dyn_pcm_assign to true, it will call
hdmi_find_pcm_slot() to find a pcm slot when hdmi/dp monitor is
connected and need to create a pcm.

So far only intel_hsw_common_init() and patch_nvhdmi() set the
dyn_pcm_assign to true, here we let tgl platforms assign the pcm slot
dynamically first, if the driver runs for a period of time and there
is no regression reported, we could set no_fixed_assgin to true in
the intel_hsw_common_init(), and then set it to true in the
patch_nvhdmi().

This change comes from the discussion between Takashi and
Kai Vehmanen. Please refer to:
https://github.com/alsa-project/alsa-lib/pull/118

Suggested-and-reviewed-by: Takashi Iwai <tiwai@suse.de>
Suggested-and-reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20210301111202.2684-1-hui.wang@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index e405be7929e31c3f7775a4f272e130484abc4c32..e6d0843ee9df2aab82ae35372549c6d0452a3402 100644 (file)
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -157,6 +157,7 @@ struct hdmi_spec {
 
        bool dyn_pin_out;
        bool dyn_pcm_assign;
+       bool dyn_pcm_no_legacy;
        bool intel_hsw_fixup;   /* apply Intel platform-specific fixups */
        /*
         * Non-generic VIA/NVIDIA specific
@@ -1345,6 +1346,12 @@ static int hdmi_find_pcm_slot(struct hdmi_spec *spec,
 {
        int i;
 
+       /* on the new machines, try to assign the pcm slot dynamically,
+        * not use the preferred fixed map (legacy way) anymore.
+        */
+       if (spec->dyn_pcm_no_legacy)
+               goto last_try;
+
        /*
         * generic_hdmi_build_pcms() may allocate extra PCMs on some
         * platforms (with maximum of 'num_nids + dev_num - 1')
@@ -1374,6 +1381,7 @@ static int hdmi_find_pcm_slot(struct hdmi_spec *spec,
                        return i;
        }
 
+ last_try:
        /* the last try; check the empty slots in pins */
        for (i = 0; i < spec->num_nids; i++) {
                if (!test_bit(i, &spec->pcm_bitmap))
@@ -2987,8 +2995,16 @@ static int patch_i915_tgl_hdmi(struct hda_codec *codec)
         * the index indicate the port number.
         */
        static const int map[] = {0x4, 0x6, 0x8, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf};
+       int ret;
 
-       return intel_hsw_common_init(codec, 0x02, map, ARRAY_SIZE(map));
+       ret = intel_hsw_common_init(codec, 0x02, map, ARRAY_SIZE(map));
+       if (!ret) {
+               struct hdmi_spec *spec = codec->spec;
+
+               spec->dyn_pcm_no_legacy = true;
+       }
+
+       return ret;
 }
 
 /* Intel Baytrail and Braswell; with eld notifier */