ALSA: hda - Cache pin-cap values

Added snd_hda_query_pin_caps() to read and cache pin-cap values
to avoid too frequently issuing the same verbs.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_codec.c

@@ -1052,6 +1052,7 @@ EXPORT_SYMBOL_HDA(snd_hda_codec_cleanup_stream);
 
 /* FIXME: more better hash key? */
 #define HDA_HASH_KEY(nid,dir,idx) (u32)((nid) + ((idx) << 16) + ((dir) << 24))
+#define HDA_HASH_PINCAP_KEY(nid) (u32)((nid) + (0x02 << 24))
 #define INFO_AMP_CAPS	(1<<0)
 #define INFO_AMP_VOL(ch)	(1 << (1 + (ch)))
 
@@ -1142,6 +1143,21 @@ int snd_hda_override_amp_caps(struct hda_codec *codec, hda_nid_t nid, int dir,
 }
 EXPORT_SYMBOL_HDA(snd_hda_override_amp_caps);
 
+u32 snd_hda_query_pin_caps(struct hda_codec *codec, hda_nid_t nid)
+{
+	struct hda_amp_info *info;
+
+	info = get_alloc_amp_hash(codec, HDA_HASH_PINCAP_KEY(nid));
+	if (!info)
+		return 0;
+	if (!info->head.val) {
+		info->amp_caps = snd_hda_param_read(codec, nid, AC_PAR_PIN_CAP);
+		info->head.val |= INFO_AMP_CAPS;
+	}
+	return info->amp_caps;
+}
+EXPORT_SYMBOL_HDA(snd_hda_query_pin_caps);
+
 /*
  * read the current volume to info
  * if the cache exists, read the cache value.